-/* mdb.c - memory-mapped database library */
+/** @file mdb.c
+ * @brief memory-mapped database library
+ *
+ * A Btree-based database management library modeled loosely on the
+ * BerkeleyDB API, but much simplified.
+ */
/*
- * Copyright 2011 Howard Chu, Symas Corp.
+ * Copyright 2011-2012 Howard Chu, Symas Corp.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
*/
#include <sys/types.h>
#include <sys/stat.h>
-#include <sys/queue.h>
#include <sys/param.h>
+#ifdef _WIN32
+#include <windows.h>
+#else
#include <sys/uio.h>
#include <sys/mman.h>
#ifdef HAVE_SYS_FILE_H
#include <sys/file.h>
#endif
#include <fcntl.h>
+#endif
#include <assert.h>
#include <errno.h>
+#include <limits.h>
#include <stddef.h>
-#include <stdint.h>
+#include <inttypes.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
+
+#if !(defined(BYTE_ORDER) || defined(__BYTE_ORDER))
+#include <resolv.h> /* defines BYTE_ORDER on HPUX and Solaris */
+#endif
+
+#ifndef _WIN32
#include <pthread.h>
+#ifdef __APPLE__
+#include <semaphore.h>
+#endif
+#endif
-#include "mdb.h"
+#ifdef USE_VALGRIND
+#include <valgrind/memcheck.h>
+#define VGMEMP_CREATE(h,r,z) VALGRIND_CREATE_MEMPOOL(h,r,z)
+#define VGMEMP_ALLOC(h,a,s) VALGRIND_MEMPOOL_ALLOC(h,a,s)
+#define VGMEMP_FREE(h,a) VALGRIND_MEMPOOL_FREE(h,a)
+#define VGMEMP_DESTROY(h) VALGRIND_DESTROY_MEMPOOL(h)
+#define VGMEMP_DEFINED(a,s) VALGRIND_MAKE_MEM_DEFINED(a,s)
+#else
+#define VGMEMP_CREATE(h,r,z)
+#define VGMEMP_ALLOC(h,a,s)
+#define VGMEMP_FREE(h,a)
+#define VGMEMP_DESTROY(h)
+#define VGMEMP_DEFINED(a,s)
+#endif
+
+#ifndef BYTE_ORDER
+# if (defined(_LITTLE_ENDIAN) || defined(_BIG_ENDIAN)) && !(defined(_LITTLE_ENDIAN) && defined(_BIG_ENDIAN))
+/* Solaris just defines one or the other */
+# define LITTLE_ENDIAN 1234
+# define BIG_ENDIAN 4321
+# ifdef _LITTLE_ENDIAN
+# define BYTE_ORDER LITTLE_ENDIAN
+# else
+# define BYTE_ORDER BIG_ENDIAN
+# endif
+# else
+# define BYTE_ORDER __BYTE_ORDER
+# endif
+#endif
-#define ULONG unsigned long
-typedef ULONG pgno_t;
+#ifndef LITTLE_ENDIAN
+#define LITTLE_ENDIAN __LITTLE_ENDIAN
+#endif
+#ifndef BIG_ENDIAN
+#define BIG_ENDIAN __BIG_ENDIAN
+#endif
+#if defined(__i386) || defined(__x86_64)
+#define MISALIGNED_OK 1
+#endif
+
+#include "mdb.h"
#include "midl.h"
-#ifndef DEBUG
-#define DEBUG 1
+#if (BYTE_ORDER == LITTLE_ENDIAN) == (BYTE_ORDER == BIG_ENDIAN)
+# error "Unknown or unsupported endianness (BYTE_ORDER)"
+#elif (-6 & 5) || CHAR_BIT != 8 || UINT_MAX < 0xffffffff || ULONG_MAX % 0xFFFF
+# error "Two's complement, reasonably sized integer types, please"
+#endif
+
+/** @defgroup internal MDB Internals
+ * @{
+ */
+/** @defgroup compat Windows Compatibility Macros
+ * A bunch of macros to minimize the amount of platform-specific ifdefs
+ * needed throughout the rest of the code. When the features this library
+ * needs are similar enough to POSIX to be hidden in a one-or-two line
+ * replacement, this macro approach is used.
+ * @{
+ */
+#ifdef _WIN32
+#define pthread_t DWORD
+#define pthread_mutex_t HANDLE
+#define pthread_key_t DWORD
+#define pthread_self() GetCurrentThreadId()
+#define pthread_key_create(x,y) (*(x) = TlsAlloc())
+#define pthread_key_delete(x) TlsFree(x)
+#define pthread_getspecific(x) TlsGetValue(x)
+#define pthread_setspecific(x,y) TlsSetValue(x,y)
+#define pthread_mutex_unlock(x) ReleaseMutex(x)
+#define pthread_mutex_lock(x) WaitForSingleObject(x, INFINITE)
+#define LOCK_MUTEX_R(env) pthread_mutex_lock((env)->me_rmutex)
+#define UNLOCK_MUTEX_R(env) pthread_mutex_unlock((env)->me_rmutex)
+#define LOCK_MUTEX_W(env) pthread_mutex_lock((env)->me_wmutex)
+#define UNLOCK_MUTEX_W(env) pthread_mutex_unlock((env)->me_wmutex)
+#define getpid() GetCurrentProcessId()
+#define fdatasync(fd) (!FlushFileBuffers(fd))
+#define ErrCode() GetLastError()
+#define GET_PAGESIZE(x) {SYSTEM_INFO si; GetSystemInfo(&si); (x) = si.dwPageSize;}
+#define close(fd) CloseHandle(fd)
+#define munmap(ptr,len) UnmapViewOfFile(ptr)
+#else
+#ifdef __APPLE__
+#define LOCK_MUTEX_R(env) sem_wait((env)->me_rmutex)
+#define UNLOCK_MUTEX_R(env) sem_post((env)->me_rmutex)
+#define LOCK_MUTEX_W(env) sem_wait((env)->me_wmutex)
+#define UNLOCK_MUTEX_W(env) sem_post((env)->me_wmutex)
+#define fdatasync(fd) fsync(fd)
+#else
+#ifdef ANDROID
+#define fdatasync(fd) fsync(fd)
+#endif
+ /** Lock the reader mutex.
+ */
+#define LOCK_MUTEX_R(env) pthread_mutex_lock(&(env)->me_txns->mti_mutex)
+ /** Unlock the reader mutex.
+ */
+#define UNLOCK_MUTEX_R(env) pthread_mutex_unlock(&(env)->me_txns->mti_mutex)
+
+ /** Lock the writer mutex.
+ * Only a single write transaction is allowed at a time. Other writers
+ * will block waiting for this mutex.
+ */
+#define LOCK_MUTEX_W(env) pthread_mutex_lock(&(env)->me_txns->mti_wmutex)
+ /** Unlock the writer mutex.
+ */
+#define UNLOCK_MUTEX_W(env) pthread_mutex_unlock(&(env)->me_txns->mti_wmutex)
+#endif /* __APPLE__ */
+
+ /** Get the error code for the last failed system function.
+ */
+#define ErrCode() errno
+
+ /** An abstraction for a file handle.
+ * On POSIX systems file handles are small integers. On Windows
+ * they're opaque pointers.
+ */
+#define HANDLE int
+
+ /** A value for an invalid file handle.
+ * Mainly used to initialize file variables and signify that they are
+ * unused.
+ */
+#define INVALID_HANDLE_VALUE (-1)
+
+ /** Get the size of a memory page for the system.
+ * This is the basic size that the platform's memory manager uses, and is
+ * fundamental to the use of memory-mapped files.
+ */
+#define GET_PAGESIZE(x) ((x) = sysconf(_SC_PAGE_SIZE))
+#endif
+
+#if defined(_WIN32) || defined(__APPLE__)
+#define MNAME_LEN 32
+#else
+#define MNAME_LEN (sizeof(pthread_mutex_t))
+#endif
+
+/** @} */
+
+#ifndef _WIN32
+/** A flag for opening a file and requesting synchronous data writes.
+ * This is only used when writing a meta page. It's not strictly needed;
+ * we could just do a normal write and then immediately perform a flush.
+ * But if this flag is available it saves us an extra system call.
+ *
+ * @note If O_DSYNC is undefined but exists in /usr/include,
+ * preferably set some compiler flag to get the definition.
+ * Otherwise compile with the less efficient -DMDB_DSYNC=O_SYNC.
+ */
+#ifndef MDB_DSYNC
+# define MDB_DSYNC O_DSYNC
+#endif
+#endif
+
+/** Function for flushing the data of a file. Define this to fsync
+ * if fdatasync() is not supported.
+ */
+#ifndef MDB_FDATASYNC
+# define MDB_FDATASYNC fdatasync
+#endif
+
+ /** A page number in the database.
+ * Note that 64 bit page numbers are overkill, since pages themselves
+ * already represent 12-13 bits of addressable memory, and the OS will
+ * always limit applications to a maximum of 63 bits of address space.
+ *
+ * @note In the #MDB_node structure, we only store 48 bits of this value,
+ * which thus limits us to only 60 bits of addressable data.
+ */
+typedef ID pgno_t;
+
+ /** A transaction ID.
+ * See struct MDB_txn.mt_txnid for details.
+ */
+typedef ID txnid_t;
+
+/** @defgroup debug Debug Macros
+ * @{
+ */
+#ifndef MDB_DEBUG
+ /** Enable debug output.
+ * Set this to 1 for copious tracing. Set to 2 to add dumps of all IDLs
+ * read from and written to the database (used for free space management).
+ */
+#define MDB_DEBUG 0
#endif
-#if DEBUG && defined(__GNUC__)
-# define DPRINTF(fmt, ...) \
- fprintf(stderr, "%s:%d: " fmt "\n", __func__, __LINE__, ##__VA_ARGS__)
+#if !(__STDC_VERSION__ >= 199901L || defined(__GNUC__))
+# define DPRINTF (void) /* Vararg macros may be unsupported */
+#elif MDB_DEBUG
+ /** Print a debug message with printf formatting. */
+# define DPRINTF(fmt, ...) /**< Requires 2 or more args */ \
+ fprintf(stderr, "%s:%d " fmt "\n", __func__, __LINE__, __VA_ARGS__)
#else
-# define DPRINTF(...) ((void) 0)
+# define DPRINTF(fmt, ...) ((void) 0)
#endif
+ /** Print a debug string.
+ * The string is printed literally, with no format processing.
+ */
+#define DPUTS(arg) DPRINTF("%s", arg)
+/** @} */
+
+ /** A default memory page size.
+ * The actual size is platform-dependent, but we use this for
+ * boot-strapping. We probably should not be using this any more.
+ * The #GET_PAGESIZE() macro is used to get the actual size.
+ *
+ * Note that we don't currently support Huge pages. On Linux,
+ * regular data files cannot use Huge pages, and in general
+ * Huge pages aren't actually pageable. We rely on the OS
+ * demand-pager to read our data and page it out when memory
+ * pressure from other processes is high. So until OSs have
+ * actual paging support for Huge pages, they're not viable.
+ */
+#define MDB_PAGESIZE 4096
+
+ /** The minimum number of keys required in a database page.
+ * Setting this to a larger value will place a smaller bound on the
+ * maximum size of a data item. Data items larger than this size will
+ * be pushed into overflow pages instead of being stored directly in
+ * the B-tree node. This value used to default to 4. With a page size
+ * of 4096 bytes that meant that any item larger than 1024 bytes would
+ * go into an overflow page. That also meant that on average 2-3KB of
+ * each overflow page was wasted space. The value cannot be lower than
+ * 2 because then there would no longer be a tree structure. With this
+ * value, items larger than 2KB will go into overflow pages, and on
+ * average only 1KB will be wasted.
+ */
+#define MDB_MINKEYS 2
-#define PAGESIZE 4096
-#define MDB_MINKEYS 4
+ /** A stamp that identifies a file as an MDB file.
+ * There's nothing special about this value other than that it is easily
+ * recognizable, and it will reflect any byte order mismatches.
+ */
#define MDB_MAGIC 0xBEEFC0DE
+
+ /** The version number for a database's file format. */
#define MDB_VERSION 1
+
+ /** The maximum size of a key in the database.
+ * While data items have essentially unbounded size, we require that
+ * keys all fit onto a regular page. This limit could be raised a bit
+ * further if needed; to something just under #MDB_PAGESIZE / #MDB_MINKEYS.
+ */
#define MAXKEYSIZE 511
+#if MDB_DEBUG
+ /** A key buffer.
+ * @ingroup debug
+ * This is used for printing a hex dump of a key's contents.
+ */
+#define DKBUF char kbuf[(MAXKEYSIZE*2+1)]
+ /** Display a key in hex.
+ * @ingroup debug
+ * Invoke a function to display a key in hex.
+ */
+#define DKEY(x) mdb_dkey(x, kbuf)
+#else
+#define DKBUF typedef int dummy_kbuf /* so we can put ';' after */
+#define DKEY(x) 0
+#endif
+
+/** @defgroup lazylock Lazy Locking
+ * Macros for locks that aren't actually needed.
+ * The DB view is always consistent because all writes are wrapped in
+ * the wmutex. Finer-grained locks aren't necessary.
+ * @{
+ */
+#ifndef LAZY_LOCKS
+ /** Use lazy locking. I.e., don't lock these accesses at all. */
+#define LAZY_LOCKS 1
+#endif
+#if LAZY_LOCKS
+ /** Grab the reader lock */
+#define LAZY_MUTEX_LOCK(x)
+ /** Release the reader lock */
+#define LAZY_MUTEX_UNLOCK(x)
+ /** Release the DB table reader/writer lock */
+#define LAZY_RWLOCK_UNLOCK(x)
+ /** Grab the DB table write lock */
+#define LAZY_RWLOCK_WRLOCK(x)
+ /** Grab the DB table read lock */
+#define LAZY_RWLOCK_RDLOCK(x)
+ /** Declare the DB table rwlock. Should not be followed by ';'. */
+#define LAZY_RWLOCK_DEF(x)
+ /** Initialize the DB table rwlock */
+#define LAZY_RWLOCK_INIT(x,y)
+ /** Destroy the DB table rwlock */
+#define LAZY_RWLOCK_DESTROY(x)
+#else
+#define LAZY_MUTEX_LOCK(x) pthread_mutex_lock(x)
+#define LAZY_MUTEX_UNLOCK(x) pthread_mutex_unlock(x)
+#define LAZY_RWLOCK_UNLOCK(x) pthread_rwlock_unlock(x)
+#define LAZY_RWLOCK_WRLOCK(x) pthread_rwlock_wrlock(x)
+#define LAZY_RWLOCK_RDLOCK(x) pthread_rwlock_rdlock(x)
+#define LAZY_RWLOCK_DEF(x) pthread_rwlock_t x;
+#define LAZY_RWLOCK_INIT(x,y) pthread_rwlock_init(x,y)
+#define LAZY_RWLOCK_DESTROY(x) pthread_rwlock_destroy(x)
+#endif
+/** @} */
+
+ /** An invalid page number.
+ * Mainly used to denote an empty tree.
+ */
#define P_INVALID (~0UL)
+ /** Test if a flag \b f is set in a flag word \b w. */
#define F_ISSET(w, f) (((w) & (f)) == (f))
+ /** Used for offsets within a single page.
+ * Since memory pages are typically 4 or 8KB in size, 12-13 bits,
+ * this is plenty.
+ */
typedef uint16_t indx_t;
-#define DEFAULT_READERS 126
+ /** Default size of memory map.
+ * This is certainly too small for any actual applications. Apps should always set
+ * the size explicitly using #mdb_env_set_mapsize().
+ */
#define DEFAULT_MAPSIZE 1048576
-/* Lock descriptor stuff */
+/** @defgroup readers Reader Lock Table
+ * Readers don't acquire any locks for their data access. Instead, they
+ * simply record their transaction ID in the reader table. The reader
+ * mutex is needed just to find an empty slot in the reader table. The
+ * slot's address is saved in thread-specific data so that subsequent read
+ * transactions started by the same thread need no further locking to proceed.
+ *
+ * Since the database uses multi-version concurrency control, readers don't
+ * actually need any locking. This table is used to keep track of which
+ * readers are using data from which old transactions, so that we'll know
+ * when a particular old transaction is no longer in use. Old transactions
+ * that have discarded any data pages can then have those pages reclaimed
+ * for use by a later write transaction.
+ *
+ * The lock table is constructed such that reader slots are aligned with the
+ * processor's cache line size. Any slot is only ever used by one thread.
+ * This alignment guarantees that there will be no contention or cache
+ * thrashing as threads update their own slot info, and also eliminates
+ * any need for locking when accessing a slot.
+ *
+ * A writer thread will scan every slot in the table to determine the oldest
+ * outstanding reader transaction. Any freed pages older than this will be
+ * reclaimed by the writer. The writer doesn't use any locks when scanning
+ * this table. This means that there's no guarantee that the writer will
+ * see the most up-to-date reader info, but that's not required for correct
+ * operation - all we need is to know the upper bound on the oldest reader,
+ * we don't care at all about the newest reader. So the only consequence of
+ * reading stale information here is that old pages might hang around a
+ * while longer before being reclaimed. That's actually good anyway, because
+ * the longer we delay reclaiming old pages, the more likely it is that a
+ * string of contiguous pages can be found after coalescing old pages from
+ * many old transactions together.
+ *
+ * @todo We don't actually do such coalescing yet, we grab pages from one
+ * old transaction at a time.
+ * @{
+ */
+ /** Number of slots in the reader table.
+ * This value was chosen somewhat arbitrarily. 126 readers plus a
+ * couple mutexes fit exactly into 8KB on my development machine.
+ * Applications should set the table size using #mdb_env_set_maxreaders().
+ */
+#define DEFAULT_READERS 126
+
+ /** The size of a CPU cache line in bytes. We want our lock structures
+ * aligned to this size to avoid false cache line sharing in the
+ * lock table.
+ * This value works for most CPUs. For Itanium this should be 128.
+ */
#ifndef CACHELINE
-#define CACHELINE 64 /* most CPUs. Itanium uses 128 */
+#define CACHELINE 64
#endif
+ /** The information we store in a single slot of the reader table.
+ * In addition to a transaction ID, we also record the process and
+ * thread ID that owns a slot, so that we can detect stale information,
+ * e.g. threads or processes that went away without cleaning up.
+ * @note We currently don't check for stale records. We simply re-init
+ * the table when we know that we're the only process opening the
+ * lock file.
+ */
typedef struct MDB_rxbody {
- ULONG mrb_txnid;
+ /** The current Transaction ID when this transaction began.
+ * Multiple readers that start at the same time will probably have the
+ * same ID here. Again, it's not important to exclude them from
+ * anything; all we need to know is which version of the DB they
+ * started from so we can avoid overwriting any data used in that
+ * particular version.
+ */
+ txnid_t mrb_txnid;
+ /** The process ID of the process owning this reader txn. */
pid_t mrb_pid;
+ /** The thread ID of the thread owning this txn. */
pthread_t mrb_tid;
} MDB_rxbody;
+ /** The actual reader record, with cacheline padding. */
typedef struct MDB_reader {
union {
MDB_rxbody mrx;
+ /** shorthand for mrb_txnid */
#define mr_txnid mru.mrx.mrb_txnid
#define mr_pid mru.mrx.mrb_pid
#define mr_tid mru.mrx.mrb_tid
- /* cache line alignment */
+ /** cache line alignment */
char pad[(sizeof(MDB_rxbody)+CACHELINE-1) & ~(CACHELINE-1)];
} mru;
} MDB_reader;
+ /** The header for the reader table.
+ * The table resides in a memory-mapped file. (This is a different file
+ * than is used for the main database.)
+ *
+ * For POSIX the actual mutexes reside in the shared memory of this
+ * mapped file. On Windows, mutexes are named objects allocated by the
+ * kernel; we store the mutex names in this mapped file so that other
+ * processes can grab them. This same approach is also used on
+ * MacOSX/Darwin (using named semaphores) since MacOSX doesn't support
+ * process-shared POSIX mutexes. For these cases where a named object
+ * is used, the object name is derived from a 64 bit FNV hash of the
+ * environment pathname. As such, naming collisions are extremely
+ * unlikely. If a collision occurs, the results are unpredictable.
+ */
typedef struct MDB_txbody {
+ /** Stamp identifying this as an MDB file. It must be set
+ * to #MDB_MAGIC. */
uint32_t mtb_magic;
+ /** Version number of this lock file. Must be set to #MDB_VERSION. */
uint32_t mtb_version;
+#if defined(_WIN32) || defined(__APPLE__)
+ char mtb_rmname[MNAME_LEN];
+#else
+ /** Mutex protecting access to this table.
+ * This is the reader lock that #LOCK_MUTEX_R acquires.
+ */
pthread_mutex_t mtb_mutex;
- ULONG mtb_txnid;
- uint32_t mtb_numreaders;
+#endif
+ /** The ID of the last transaction committed to the database.
+ * This is recorded here only for convenience; the value can always
+ * be determined by reading the main database meta pages.
+ */
+ txnid_t mtb_txnid;
+ /** The number of slots that have been used in the reader table.
+ * This always records the maximum count, it is not decremented
+ * when readers release their slots.
+ */
+ unsigned mtb_numreaders;
+ /** The ID of the most recent meta page in the database.
+ * This is recorded here only for convenience; the value can always
+ * be determined by reading the main database meta pages.
+ */
uint32_t mtb_me_toggle;
} MDB_txbody;
+ /** The actual reader table definition. */
typedef struct MDB_txninfo {
union {
MDB_txbody mtb;
#define mti_magic mt1.mtb.mtb_magic
#define mti_version mt1.mtb.mtb_version
#define mti_mutex mt1.mtb.mtb_mutex
+#define mti_rmname mt1.mtb.mtb_rmname
#define mti_txnid mt1.mtb.mtb_txnid
#define mti_numreaders mt1.mtb.mtb_numreaders
#define mti_me_toggle mt1.mtb.mtb_me_toggle
char pad[(sizeof(MDB_txbody)+CACHELINE-1) & ~(CACHELINE-1)];
} mt1;
union {
+#if defined(_WIN32) || defined(__APPLE__)
+ char mt2_wmname[MNAME_LEN];
+#define mti_wmname mt2.mt2_wmname
+#else
pthread_mutex_t mt2_wmutex;
#define mti_wmutex mt2.mt2_wmutex
- char pad[(sizeof(pthread_mutex_t)+CACHELINE-1) & ~(CACHELINE-1)];
+#endif
+ char pad[(MNAME_LEN+CACHELINE-1) & ~(CACHELINE-1)];
} mt2;
MDB_reader mti_readers[1];
} MDB_txninfo;
+/** @} */
-/* Common header for all page types. Overflow pages
- * occupy a number of contiguous pages with no
+/** Common header for all page types.
+ * Overflow records occupy a number of contiguous pages with no
* headers on any page after the first.
*/
-typedef struct MDB_page { /* represents a page of storage */
-#define mp_pgno mp_p.p_pgno
- union padded {
- pgno_t p_pgno; /* page number */
- void * p_pad;
+typedef struct MDB_page {
+#define mp_pgno mp_p.p_pgno
+#define mp_next mp_p.p_next
+ union {
+ pgno_t p_pgno; /**< page number */
+ void * p_next; /**< for in-memory list of freed structs */
} mp_p;
-#define P_BRANCH 0x01 /* branch page */
-#define P_LEAF 0x02 /* leaf page */
-#define P_OVERFLOW 0x04 /* overflow page */
-#define P_META 0x08 /* meta page */
-#define P_DIRTY 0x10 /* dirty page */
-#define P_LEAF2 0x20 /* DB with small, fixed size keys and no data */
- uint32_t mp_flags;
+ uint16_t mp_pad;
+/** @defgroup mdb_page Page Flags
+ * @ingroup internal
+ * Flags for the page headers.
+ * @{
+ */
+#define P_BRANCH 0x01 /**< branch page */
+#define P_LEAF 0x02 /**< leaf page */
+#define P_OVERFLOW 0x04 /**< overflow page */
+#define P_META 0x08 /**< meta page */
+#define P_DIRTY 0x10 /**< dirty page */
+#define P_LEAF2 0x20 /**< for #MDB_DUPFIXED records */
+#define P_SUBP 0x40 /**< for #MDB_DUPSORT sub-pages */
+/** @} */
+ uint16_t mp_flags; /**< @ref mdb_page */
#define mp_lower mp_pb.pb.pb_lower
#define mp_upper mp_pb.pb.pb_upper
#define mp_pages mp_pb.pb_pages
- union page_bounds {
+ union {
struct {
- indx_t pb_lower; /* lower bound of free space */
- indx_t pb_upper; /* upper bound of free space */
+ indx_t pb_lower; /**< lower bound of free space */
+ indx_t pb_upper; /**< upper bound of free space */
} pb;
- uint32_t pb_pages; /* number of overflow pages */
- struct {
- indx_t pb_ksize; /* on a LEAF2 page */
- indx_t pb_numkeys;
- } pb2;
+ uint32_t pb_pages; /**< number of overflow pages */
} mp_pb;
- indx_t mp_ptrs[1]; /* dynamic size */
+ indx_t mp_ptrs[1]; /**< dynamic size */
} MDB_page;
+ /** Size of the page header, excluding dynamic data at the end */
#define PAGEHDRSZ ((unsigned) offsetof(MDB_page, mp_ptrs))
+ /** Address of first usable data byte in a page, after the header */
+#define METADATA(p) ((void *)((char *)(p) + PAGEHDRSZ))
+
+ /** Number of nodes on a page */
#define NUMKEYS(p) (((p)->mp_lower - PAGEHDRSZ) >> 1)
+
+ /** The amount of space remaining in the page */
#define SIZELEFT(p) (indx_t)((p)->mp_upper - (p)->mp_lower)
+
+ /** The percentage of space used in the page, in tenths of a percent. */
#define PAGEFILL(env, p) (1000L * ((env)->me_psize - PAGEHDRSZ - SIZELEFT(p)) / \
((env)->me_psize - PAGEHDRSZ))
+ /** The minimum page fill factor, in tenths of a percent.
+ * Pages emptier than this are candidates for merging.
+ */
+#define FILL_THRESHOLD 250
+
+ /** Test if a page is a leaf page */
#define IS_LEAF(p) F_ISSET((p)->mp_flags, P_LEAF)
+ /** Test if a page is a LEAF2 page */
+#define IS_LEAF2(p) F_ISSET((p)->mp_flags, P_LEAF2)
+ /** Test if a page is a branch page */
#define IS_BRANCH(p) F_ISSET((p)->mp_flags, P_BRANCH)
+ /** Test if a page is an overflow page */
#define IS_OVERFLOW(p) F_ISSET((p)->mp_flags, P_OVERFLOW)
+ /** Test if a page is a sub page */
+#define IS_SUBP(p) F_ISSET((p)->mp_flags, P_SUBP)
-#define OVPAGES(size, psize) (PAGEHDRSZ + size + psize - 1) / psize;
+ /** The number of overflow pages needed to store the given size. */
+#define OVPAGES(size, psize) ((PAGEHDRSZ-1 + (size)) / (psize) + 1)
-typedef struct MDB_db {
- uint32_t md_pad;
- uint16_t md_flags;
- uint16_t md_depth;
- ULONG md_branch_pages;
- ULONG md_leaf_pages;
- ULONG md_overflow_pages;
- ULONG md_entries;
- pgno_t md_root;
-} MDB_db;
+ /** Header for a single key/data pair within a page.
+ * We guarantee 2-byte alignment for nodes.
+ */
+typedef struct MDB_node {
+ /** lo and hi are used for data size on leaf nodes and for
+ * child pgno on branch nodes. On 64 bit platforms, flags
+ * is also used for pgno. (Branch nodes have no flags).
+ * They are in host byte order in case that lets some
+ * accesses be optimized into a 32-bit word access.
+ */
+#define mn_lo mn_offset[BYTE_ORDER!=LITTLE_ENDIAN]
+#define mn_hi mn_offset[BYTE_ORDER==LITTLE_ENDIAN] /**< part of dsize or pgno */
+ unsigned short mn_offset[2]; /**< storage for #mn_lo and #mn_hi */
+/** @defgroup mdb_node Node Flags
+ * @ingroup internal
+ * Flags for node headers.
+ * @{
+ */
+#define F_BIGDATA 0x01 /**< data put on overflow page */
+#define F_SUBDATA 0x02 /**< data is a sub-database */
+#define F_DUPDATA 0x04 /**< data has duplicates */
-#define FREE_DBI 0
-#define MAIN_DBI 1
+/** valid flags for #mdb_node_add() */
+#define NODE_ADD_FLAGS (F_DUPDATA|F_SUBDATA|MDB_RESERVE|MDB_APPEND)
-typedef struct MDB_meta { /* meta (footer) page content */
- uint32_t mm_magic;
- uint32_t mm_version;
- void *mm_address; /* address for fixed mapping */
- size_t mm_mapsize; /* size of mmap region */
- MDB_db mm_dbs[2]; /* first is free space, 2nd is main db */
-#define mm_psize mm_dbs[0].md_pad
-#define mm_flags mm_dbs[0].md_flags
- pgno_t mm_last_pg; /* last used page in file */
- ULONG mm_txnid; /* txnid that committed this page */
-} MDB_meta;
+/** @} */
+ unsigned short mn_flags; /**< @ref mdb_node */
+ unsigned short mn_ksize; /**< key size */
+ char mn_data[1]; /**< key and data are appended here */
+} MDB_node;
-typedef struct MDB_dhead { /* a dirty page */
- MDB_page *md_parent;
- unsigned md_pi; /* parent index */
- int md_num;
-} MDB_dhead;
+ /** Size of the node header, excluding dynamic data at the end */
+#define NODESIZE offsetof(MDB_node, mn_data)
-typedef struct MDB_dpage {
- MDB_dhead h;
- MDB_page p;
-} MDB_dpage;
+ /** Bit position of top word in page number, for shifting mn_flags */
+#define PGNO_TOPWORD ((pgno_t)-1 > 0xffffffffu ? 32 : 0)
-typedef struct MDB_oldpages {
- struct MDB_oldpages *mo_next;
- ULONG mo_txnid;
- pgno_t mo_pages[1]; /* dynamic */
-} MDB_oldpages;
+ /** Size of a node in a branch page with a given key.
+ * This is just the node header plus the key, there is no data.
+ */
+#define INDXSIZE(k) (NODESIZE + ((k) == NULL ? 0 : (k)->mv_size))
-typedef struct MDB_pageparent {
- MDB_page *mp_page;
- MDB_page *mp_parent;
- unsigned mp_pi;
-} MDB_pageparent;
+ /** Size of a node in a leaf page with a given key and data.
+ * This is node header plus key plus data size.
+ */
+#define LEAFSIZE(k, d) (NODESIZE + (k)->mv_size + (d)->mv_size)
-static MDB_dpage *mdb_alloc_page(MDB_txn *txn, MDB_page *parent, unsigned int parent_idx, int num);
-static int mdb_touch(MDB_txn *txn, MDB_pageparent *mp);
+ /** Address of node \b i in page \b p */
+#define NODEPTR(p, i) ((MDB_node *)((char *)(p) + (p)->mp_ptrs[i]))
-typedef struct MDB_ppage { /* ordered list of pages */
- SLIST_ENTRY(MDB_ppage) mp_entry;
- MDB_page *mp_page;
- unsigned int mp_ki; /* cursor index on page */
-} MDB_ppage;
-SLIST_HEAD(page_stack, MDB_ppage);
+ /** Address of the key for the node */
+#define NODEKEY(node) (void *)((node)->mn_data)
-/* FIXME: tree depth is mostly bounded, we should just
- * use a fixed array and avoid malloc/pointer chasing
- */
-#define CURSOR_EMPTY(c) SLIST_EMPTY(&(c)->mc_stack)
-#define CURSOR_TOP(c) SLIST_FIRST(&(c)->mc_stack)
-#define CURSOR_POP(c) SLIST_REMOVE_HEAD(&(c)->mc_stack, mp_entry)
-#define CURSOR_PUSH(c,p) SLIST_INSERT_HEAD(&(c)->mc_stack, p, mp_entry)
+ /** Address of the data for a node */
+#define NODEDATA(node) (void *)((char *)(node)->mn_data + (node)->mn_ksize)
-struct MDB_xcursor;
+ /** Get the page number pointed to by a branch node */
+#define NODEPGNO(node) \
+ ((node)->mn_lo | ((pgno_t) (node)->mn_hi << 16) | \
+ (PGNO_TOPWORD ? ((pgno_t) (node)->mn_flags << PGNO_TOPWORD) : 0))
+ /** Set the page number in a branch node */
+#define SETPGNO(node,pgno) do { \
+ (node)->mn_lo = (pgno) & 0xffff; (node)->mn_hi = (pgno) >> 16; \
+ if (PGNO_TOPWORD) (node)->mn_flags = (pgno) >> PGNO_TOPWORD; } while(0)
+
+ /** Get the size of the data in a leaf node */
+#define NODEDSZ(node) ((node)->mn_lo | ((unsigned)(node)->mn_hi << 16))
+ /** Set the size of the data for a leaf node */
+#define SETDSZ(node,size) do { \
+ (node)->mn_lo = (size) & 0xffff; (node)->mn_hi = (size) >> 16;} while(0)
+ /** The size of a key in a node */
+#define NODEKSZ(node) ((node)->mn_ksize)
+
+ /** Copy a page number from src to dst */
+#ifdef MISALIGNED_OK
+#define COPY_PGNO(dst,src) dst = src
+#else
+#if SIZE_MAX > 4294967295UL
+#define COPY_PGNO(dst,src) do { \
+ unsigned short *s, *d; \
+ s = (unsigned short *)&(src); \
+ d = (unsigned short *)&(dst); \
+ *d++ = *s++; \
+ *d++ = *s++; \
+ *d++ = *s++; \
+ *d = *s; \
+} while (0)
+#else
+#define COPY_PGNO(dst,src) do { \
+ unsigned short *s, *d; \
+ s = (unsigned short *)&(src); \
+ d = (unsigned short *)&(dst); \
+ *d++ = *s++; \
+ *d = *s; \
+} while (0)
+#endif
+#endif
+ /** The address of a key in a LEAF2 page.
+ * LEAF2 pages are used for #MDB_DUPFIXED sorted-duplicate sub-DBs.
+ * There are no node headers, keys are stored contiguously.
+ */
+#define LEAF2KEY(p, i, ks) ((char *)(p) + PAGEHDRSZ + ((i)*(ks)))
-struct MDB_cursor {
- MDB_txn *mc_txn;
- struct page_stack mc_stack; /* stack of parent pages */
- MDB_dbi mc_dbi;
- short mc_initialized; /* 1 if initialized */
- short mc_eof; /* 1 if end is reached */
- struct MDB_xcursor *mc_xcursor;
-};
+ /** Set the \b node's key into \b key, if requested. */
+#define MDB_SET_KEY(node, key) { if ((key) != NULL) { \
+ (key)->mv_size = NODEKSZ(node); (key)->mv_data = NODEKEY(node); } }
-#define METADATA(p) ((void *)((char *)p + PAGEHDRSZ))
+ /** Information about a single database in the environment. */
+typedef struct MDB_db {
+ uint32_t md_pad; /**< also ksize for LEAF2 pages */
+ uint16_t md_flags; /**< @ref mdb_open */
+ uint16_t md_depth; /**< depth of this tree */
+ pgno_t md_branch_pages; /**< number of internal pages */
+ pgno_t md_leaf_pages; /**< number of leaf pages */
+ pgno_t md_overflow_pages; /**< number of overflow pages */
+ size_t md_entries; /**< number of data items */
+ pgno_t md_root; /**< the root page of this tree */
+} MDB_db;
-typedef struct MDB_node {
-#define mn_pgno mn_p.np_pgno
-#define mn_dsize mn_p.np_dsize
- union {
- pgno_t np_pgno; /* child page number */
- uint32_t np_dsize; /* leaf data size */
- } mn_p;
- unsigned int mn_flags:4;
- unsigned int mn_ksize:12; /* key size */
-#define F_BIGDATA 0x01 /* data put on overflow page */
-#define F_SUBDATA 0x02 /* data is a sub-database */
- char mn_data[1];
-} MDB_node;
+ /** Handle for the DB used to track free pages. */
+#define FREE_DBI 0
+ /** Handle for the default DB. */
+#define MAIN_DBI 1
+ /** Meta page content. */
+typedef struct MDB_meta {
+ /** Stamp identifying this as an MDB file. It must be set
+ * to #MDB_MAGIC. */
+ uint32_t mm_magic;
+ /** Version number of this lock file. Must be set to #MDB_VERSION. */
+ uint32_t mm_version;
+ void *mm_address; /**< address for fixed mapping */
+ size_t mm_mapsize; /**< size of mmap region */
+ MDB_db mm_dbs[2]; /**< first is free space, 2nd is main db */
+ /** The size of pages used in this DB */
+#define mm_psize mm_dbs[0].md_pad
+ /** Any persistent environment flags. @ref mdb_env */
+#define mm_flags mm_dbs[0].md_flags
+ pgno_t mm_last_pg; /**< last used page in file */
+ txnid_t mm_txnid; /**< txnid that committed this page */
+} MDB_meta;
+
+ /** Buffer for a stack-allocated dirty page.
+ * The members define size and alignment, and silence type
+ * aliasing warnings. They are not used directly; that could
+ * mean incorrectly using several union members in parallel.
+ */
+typedef union MDB_pagebuf {
+ char mb_raw[MDB_PAGESIZE];
+ MDB_page mb_page;
+ struct {
+ char mm_pad[PAGEHDRSZ];
+ MDB_meta mm_meta;
+ } mb_metabuf;
+} MDB_pagebuf;
+
+ /** Auxiliary DB info.
+ * The information here is mostly static/read-only. There is
+ * only a single copy of this record in the environment.
+ */
typedef struct MDB_dbx {
- MDB_val md_name;
- MDB_cmp_func *md_cmp; /* user compare function */
- MDB_cmp_func *md_dcmp; /* user dupsort function */
- MDB_rel_func *md_rel; /* user relocate function */
- MDB_dbi md_parent;
- unsigned int md_dirty;
+ MDB_val md_name; /**< name of the database */
+ MDB_cmp_func *md_cmp; /**< function for comparing keys */
+ MDB_cmp_func *md_dcmp; /**< function for comparing data items */
+ MDB_rel_func *md_rel; /**< user relocate function */
+ void *md_relctx; /**< user-provided context for md_rel */
} MDB_dbx;
+ /** A database transaction.
+ * Every operation requires a transaction handle.
+ */
struct MDB_txn {
- pgno_t mt_next_pgno; /* next unallocated page */
- ULONG mt_txnid;
- ULONG mt_oldest;
- MDB_env *mt_env;
- pgno_t *mt_free_pgs; /* this is an IDL */
+ MDB_txn *mt_parent; /**< parent of a nested txn */
+ MDB_txn *mt_child; /**< nested txn under this txn */
+ pgno_t mt_next_pgno; /**< next unallocated page */
+ /** The ID of this transaction. IDs are integers incrementing from 1.
+ * Only committed write transactions increment the ID. If a transaction
+ * aborts, the ID may be re-used by the next writer.
+ */
+ txnid_t mt_txnid;
+ MDB_env *mt_env; /**< the DB environment */
+ /** The list of pages that became unused during this transaction.
+ */
+ IDL mt_free_pgs;
union {
- MIDL2 *dirty_list; /* modified pages */
- MDB_reader *reader;
+ ID2L dirty_list; /**< modified pages */
+ MDB_reader *reader; /**< this thread's slot in the reader table */
} mt_u;
- MDB_dbx *mt_dbxs; /* array */
+ /** Array of records for each DB known in the environment. */
+ MDB_dbx *mt_dbxs;
+ /** Array of MDB_db records for each known DB */
MDB_db *mt_dbs;
- unsigned int mt_numdbs;
+/** @defgroup mt_dbflag Transaction DB Flags
+ * @ingroup internal
+ * @{
+ */
+#define DB_DIRTY 0x01 /**< DB was written in this txn */
+#define DB_STALE 0x02 /**< DB record is older than txnID */
+/** @} */
+ /** Array of cursors for each DB */
+ MDB_cursor **mt_cursors;
+ /** Array of flags for each DB */
+ unsigned char *mt_dbflags;
+ /** Number of DB records in use. This number only ever increments;
+ * we don't decrement it when individual DB handles are closed.
+ */
+ MDB_dbi mt_numdbs;
+
+/** @defgroup mdb_txn Transaction Flags
+ * @ingroup internal
+ * @{
+ */
+#define MDB_TXN_RDONLY 0x01 /**< read-only transaction */
+#define MDB_TXN_ERROR 0x02 /**< an error has occurred */
+/** @} */
+ unsigned int mt_flags; /**< @ref mdb_txn */
+ /** Tracks which of the two meta pages was used at the start
+ * of this transaction.
+ */
+ unsigned int mt_toggle;
+};
-#define MDB_TXN_RDONLY 0x01 /* read-only transaction */
-#define MDB_TXN_ERROR 0x02 /* an error has occurred */
-#define MDB_TXN_METOGGLE 0x04 /* used meta page 1 */
- unsigned int mt_flags;
+/** Enough space for 2^32 nodes with minimum of 2 keys per node. I.e., plenty.
+ * At 4 keys per node, enough for 2^64 nodes, so there's probably no need to
+ * raise this on a 64 bit machine.
+ */
+#define CURSOR_STACK 32
+
+struct MDB_xcursor;
+
+ /** Cursors are used for all DB operations */
+struct MDB_cursor {
+ /** Next cursor on this DB in this txn */
+ MDB_cursor *mc_next;
+ /** Original cursor if this is a shadow */
+ MDB_cursor *mc_orig;
+ /** Context used for databases with #MDB_DUPSORT, otherwise NULL */
+ struct MDB_xcursor *mc_xcursor;
+ /** The transaction that owns this cursor */
+ MDB_txn *mc_txn;
+ /** The database handle this cursor operates on */
+ MDB_dbi mc_dbi;
+ /** The database record for this cursor */
+ MDB_db *mc_db;
+ /** The database auxiliary record for this cursor */
+ MDB_dbx *mc_dbx;
+ /** The @ref mt_dbflag for this database */
+ unsigned char *mc_dbflag;
+ unsigned short mc_snum; /**< number of pushed pages */
+ unsigned short mc_top; /**< index of top page, normally mc_snum-1 */
+/** @defgroup mdb_cursor Cursor Flags
+ * @ingroup internal
+ * Cursor state flags.
+ * @{
+ */
+#define C_INITIALIZED 0x01 /**< cursor has been initialized and is valid */
+#define C_EOF 0x02 /**< No more data */
+#define C_SUB 0x04 /**< Cursor is a sub-cursor */
+#define C_SHADOW 0x08 /**< Cursor is a dup from a parent txn */
+#define C_ALLOCD 0x10 /**< Cursor was malloc'd */
+/** @} */
+ unsigned int mc_flags; /**< @ref mdb_cursor */
+ MDB_page *mc_pg[CURSOR_STACK]; /**< stack of pushed pages */
+ indx_t mc_ki[CURSOR_STACK]; /**< stack of page indices */
};
-/* Context for sorted-dup records */
+ /** Context for sorted-dup records.
+ * We could have gone to a fully recursive design, with arbitrarily
+ * deep nesting of sub-databases. But for now we only handle these
+ * levels - main DB, optional sub-DB, sorted-duplicate DB.
+ */
typedef struct MDB_xcursor {
+ /** A sub-cursor for traversing the Dup DB */
MDB_cursor mx_cursor;
- MDB_txn mx_txn;
- MDB_dbx mx_dbxs[4];
- MDB_db mx_dbs[4];
+ /** The database record for this Dup DB */
+ MDB_db mx_db;
+ /** The auxiliary DB record for this Dup DB */
+ MDB_dbx mx_dbx;
+ /** The @ref mt_dbflag for this Dup DB */
+ unsigned char mx_dbflag;
} MDB_xcursor;
+ /** A set of pages freed by an earlier transaction. */
+typedef struct MDB_oldpages {
+ /** Usually we only read one record from the FREEDB at a time, but
+ * in case we read more, this will chain them together.
+ */
+ struct MDB_oldpages *mo_next;
+ /** The ID of the transaction in which these pages were freed. */
+ txnid_t mo_txnid;
+ /** An #IDL of the pages */
+ pgno_t mo_pages[1]; /* dynamic */
+} MDB_oldpages;
+
+ /** The database environment. */
struct MDB_env {
- int me_fd;
- int me_lfd;
- int me_mfd; /* just for writing the meta pages */
+ HANDLE me_fd; /**< The main data file */
+ HANDLE me_lfd; /**< The lock file */
+ HANDLE me_mfd; /**< just for writing the meta pages */
+ /** Failed to update the meta page. Probably an I/O error. */
#define MDB_FATAL_ERROR 0x80000000U
- uint32_t me_flags;
- uint32_t me_extrapad; /* unused for now */
- unsigned int me_maxreaders;
- unsigned int me_numdbs;
- unsigned int me_maxdbs;
- char *me_path;
- char *me_map;
- MDB_txninfo *me_txns;
- MDB_meta *me_metas[2];
- MDB_meta *me_meta;
- MDB_txn *me_txn; /* current write transaction */
- size_t me_mapsize;
- off_t me_size; /* current file size */
- pgno_t me_maxpg; /* me_mapsize / me_psize */
- unsigned int me_psize;
- unsigned int me_db_toggle;
- MDB_dbx *me_dbxs; /* array */
- MDB_db *me_dbs[2];
- MDB_oldpages *me_pghead;
- pthread_key_t me_txkey; /* thread-key for readers */
- pgno_t me_free_pgs[MDB_IDL_UM_SIZE];
- MIDL2 me_dirty_list[MDB_IDL_DB_SIZE];
+ uint32_t me_flags; /**< @ref mdb_env */
+ uint32_t me_extrapad; /**< unused for now */
+ unsigned int me_maxreaders; /**< size of the reader table */
+ MDB_dbi me_numdbs; /**< number of DBs opened */
+ MDB_dbi me_maxdbs; /**< size of the DB table */
+ char *me_path; /**< path to the DB files */
+ char *me_map; /**< the memory map of the data file */
+ MDB_txninfo *me_txns; /**< the memory map of the lock file */
+ MDB_meta *me_metas[2]; /**< pointers to the two meta pages */
+ MDB_txn *me_txn; /**< current write transaction */
+ size_t me_mapsize; /**< size of the data memory map */
+ off_t me_size; /**< current file size */
+ pgno_t me_maxpg; /**< me_mapsize / me_psize */
+ unsigned int me_psize; /**< size of a page, from #GET_PAGESIZE */
+ unsigned int me_db_toggle; /**< which DB table is current */
+ txnid_t me_wtxnid; /**< ID of last txn we committed */
+ txnid_t me_pgfirst; /**< ID of first old page record we used */
+ txnid_t me_pglast; /**< ID of last old page record we used */
+ MDB_dbx *me_dbxs; /**< array of static DB info */
+ MDB_db *me_dbs[2]; /**< two arrays of MDB_db info */
+ MDB_oldpages *me_pghead; /**< list of old page records */
+ pthread_key_t me_txkey; /**< thread-key for readers */
+ MDB_page *me_dpages; /**< list of malloc'd blocks for re-use */
+ /** IDL of pages that became unused in a write txn */
+ IDL me_free_pgs;
+ /** ID2L of pages that were written during a write txn */
+ ID2 me_dirty_list[MDB_IDL_UM_SIZE];
+ /** rwlock for the DB tables, if #LAZY_LOCKS is false */
+ LAZY_RWLOCK_DEF(me_dblock)
+#ifdef _WIN32
+ HANDLE me_rmutex; /* Windows mutexes don't reside in shared mem */
+ HANDLE me_wmutex;
+#endif
+#ifdef __APPLE__
+ sem_t *me_rmutex; /* Apple doesn't support shared mutexes */
+ sem_t *me_wmutex;
+#endif
};
+ /** max number of pages to commit in one writev() call */
+#define MDB_COMMIT_PAGES 64
+#if defined(IOV_MAX) && IOV_MAX < MDB_COMMIT_PAGES
+#undef MDB_COMMIT_PAGES
+#define MDB_COMMIT_PAGES IOV_MAX
+#endif
-#define NODESIZE offsetof(MDB_node, mn_data)
-
-#define INDXSIZE(k) (NODESIZE + ((k) == NULL ? 0 : (k)->mv_size))
-#define LEAFSIZE(k, d) (NODESIZE + (k)->mv_size + (d)->mv_size)
-#define NODEPTR(p, i) ((MDB_node *)((char *)(p) + (p)->mp_ptrs[i]))
-#define NODEKEY(node) (void *)((node)->mn_data)
-#define NODEDATA(node) (void *)((char *)(node)->mn_data + (node)->mn_ksize)
-#define NODEPGNO(node) ((node)->mn_pgno)
-#define NODEDSZ(node) ((node)->mn_dsize)
-
-#define MDB_COMMIT_PAGES 64 /* max number of pages to write in one commit */
+static MDB_page *mdb_page_alloc(MDB_cursor *mc, int num);
+static MDB_page *mdb_page_new(MDB_cursor *mc, uint32_t flags, int num);
+static int mdb_page_touch(MDB_cursor *mc);
-static int mdb_search_page_root(MDB_txn *txn,
- MDB_dbi dbi, MDB_val *key,
- MDB_cursor *cursor, int modify,
- MDB_pageparent *mpp);
-static int mdb_search_page(MDB_txn *txn,
- MDB_dbi dbi, MDB_val *key,
- MDB_cursor *cursor, int modify,
- MDB_pageparent *mpp);
+static int mdb_page_get(MDB_txn *txn, pgno_t pgno, MDB_page **mp);
+static int mdb_page_search_root(MDB_cursor *mc,
+ MDB_val *key, int modify);
+static int mdb_page_search(MDB_cursor *mc,
+ MDB_val *key, int modify);
+static int mdb_page_merge(MDB_cursor *csrc, MDB_cursor *cdst);
+static int mdb_page_split(MDB_cursor *mc, MDB_val *newkey, MDB_val *newdata,
+ pgno_t newpgno, unsigned int nflags);
static int mdb_env_read_header(MDB_env *env, MDB_meta *meta);
static int mdb_env_read_meta(MDB_env *env, int *which);
static int mdb_env_write_meta(MDB_txn *txn);
-static MDB_page *mdb_get_page(MDB_txn *txn, pgno_t pgno);
-
-static MDB_node *mdb_search_node(MDB_txn *txn, MDB_dbi dbi, MDB_page *mp,
- MDB_val *key, int *exactp, unsigned int *kip);
-static int mdb_add_node(MDB_txn *txn, MDB_dbi dbi, MDB_page *mp,
- indx_t indx, MDB_val *key, MDB_val *data,
- pgno_t pgno, uint8_t flags);
-static void mdb_del_node(MDB_page *mp, indx_t indx);
-static int mdb_del0(MDB_txn *txn, MDB_dbi dbi, unsigned int ki,
- MDB_pageparent *mpp, MDB_node *leaf);
-static int mdb_put0(MDB_txn *txn, MDB_dbi dbi,
- MDB_val *key, MDB_val *data, unsigned int flags);
-static int mdb_read_data(MDB_txn *txn, MDB_node *leaf, MDB_val *data);
-
-static int mdb_rebalance(MDB_txn *txn, MDB_dbi dbi, MDB_pageparent *mp);
-static int mdb_update_key(MDB_page *mp, indx_t indx, MDB_val *key);
-static int mdb_move_node(MDB_txn *txn, MDB_dbi dbi,
- MDB_pageparent *src, indx_t srcindx,
- MDB_pageparent *dst, indx_t dstindx);
-static int mdb_merge(MDB_txn *txn, MDB_dbi dbi, MDB_pageparent *src,
- MDB_pageparent *dst);
-static int mdb_split(MDB_txn *txn, MDB_dbi dbi, MDB_page **mpp,
- unsigned int *newindxp, MDB_val *newkey,
- MDB_val *newdata, pgno_t newpgno);
-static MDB_dpage *mdb_new_page(MDB_txn *txn, MDB_dbi dbi, uint32_t flags, int num);
-
-static void cursor_pop_page(MDB_cursor *cursor);
-static MDB_ppage *cursor_push_page(MDB_cursor *cursor,
- MDB_page *mp);
-
-static int mdb_set_key(MDB_node *node, MDB_val *key);
-static int mdb_sibling(MDB_cursor *cursor, int move_right);
-static int mdb_cursor_next(MDB_cursor *cursor,
- MDB_val *key, MDB_val *data, MDB_cursor_op op);
-static int mdb_cursor_prev(MDB_cursor *cursor,
- MDB_val *key, MDB_val *data, MDB_cursor_op op);
-static int mdb_cursor_set(MDB_cursor *cursor,
- MDB_val *key, MDB_val *data, MDB_cursor_op op, int *exactp);
-static int mdb_cursor_first(MDB_cursor *cursor,
- MDB_val *key, MDB_val *data);
-static int mdb_cursor_last(MDB_cursor *cursor,
- MDB_val *key, MDB_val *data);
-
-static void mdb_xcursor_init0(MDB_txn *txn, MDB_dbi dbi, MDB_xcursor *mx);
-static void mdb_xcursor_init1(MDB_txn *txn, MDB_dbi dbi, MDB_xcursor *mx, MDB_node *node);
-static void mdb_xcursor_fini(MDB_txn *txn, MDB_dbi dbi, MDB_xcursor *mx);
-
-static size_t mdb_leaf_size(MDB_env *env, MDB_val *key,
- MDB_val *data);
-static size_t mdb_branch_size(MDB_env *env, MDB_val *key);
-
-static int memncmp(const void *s1, size_t n1,
- const void *s2, size_t n2);
-static int memnrcmp(const void *s1, size_t n1,
- const void *s2, size_t n2);
-
-static int
-memncmp(const void *s1, size_t n1, const void *s2, size_t n2)
-{
- int diff, len_diff = -1;
-
- if (n1 >= n2) {
- len_diff = (n1 > n2);
- n1 = n2;
- }
- diff = memcmp(s1, s2, n1);
- return diff ? diff : len_diff;
-}
-
-static int
-memnrcmp(const void *s1, size_t n1, const void *s2, size_t n2)
-{
- const unsigned char *p1, *p2, *p1_lim;
-
- if (n2 == 0)
- return n1 != 0;
- if (n1 == 0)
- return -1;
- p1 = (const unsigned char *)s1 + n1 - 1;
- p2 = (const unsigned char *)s2 + n2 - 1;
-
- for (p1_lim = (n1 <= n2 ? s1 : s2); *p1 == *p2; p1--, p2--) {
- if (p1 == p1_lim)
- return (p1 != s1) ? (p1 != p2) : (p2 != s2) ? -1 : 0;
- }
- return *p1 - *p2;
-}
+static MDB_node *mdb_node_search(MDB_cursor *mc, MDB_val *key, int *exactp);
+static int mdb_node_add(MDB_cursor *mc, indx_t indx,
+ MDB_val *key, MDB_val *data, pgno_t pgno, unsigned int flags);
+static void mdb_node_del(MDB_page *mp, indx_t indx, int ksize);
+static void mdb_node_shrink(MDB_page *mp, indx_t indx);
+static int mdb_node_move(MDB_cursor *csrc, MDB_cursor *cdst);
+static int mdb_node_read(MDB_txn *txn, MDB_node *leaf, MDB_val *data);
+static size_t mdb_leaf_size(MDB_env *env, MDB_val *key, MDB_val *data);
+static size_t mdb_branch_size(MDB_env *env, MDB_val *key);
+
+static int mdb_rebalance(MDB_cursor *mc);
+static int mdb_update_key(MDB_page *mp, indx_t indx, MDB_val *key);
+
+static void mdb_cursor_pop(MDB_cursor *mc);
+static int mdb_cursor_push(MDB_cursor *mc, MDB_page *mp);
+
+static int mdb_cursor_del0(MDB_cursor *mc, MDB_node *leaf);
+static int mdb_cursor_sibling(MDB_cursor *mc, int move_right);
+static int mdb_cursor_next(MDB_cursor *mc, MDB_val *key, MDB_val *data, MDB_cursor_op op);
+static int mdb_cursor_prev(MDB_cursor *mc, MDB_val *key, MDB_val *data, MDB_cursor_op op);
+static int mdb_cursor_set(MDB_cursor *mc, MDB_val *key, MDB_val *data, MDB_cursor_op op,
+ int *exactp);
+static int mdb_cursor_first(MDB_cursor *mc, MDB_val *key, MDB_val *data);
+static int mdb_cursor_last(MDB_cursor *mc, MDB_val *key, MDB_val *data);
+
+static void mdb_cursor_init(MDB_cursor *mc, MDB_txn *txn, MDB_dbi dbi, MDB_xcursor *mx);
+static void mdb_xcursor_init0(MDB_cursor *mc);
+static void mdb_xcursor_init1(MDB_cursor *mc, MDB_node *node);
+
+static int mdb_drop0(MDB_cursor *mc, int subs);
+static void mdb_default_cmp(MDB_txn *txn, MDB_dbi dbi);
+
+/** @cond */
+static MDB_cmp_func mdb_cmp_memn, mdb_cmp_memnr, mdb_cmp_int, mdb_cmp_cint, mdb_cmp_long;
+/** @endcond */
+
+#ifdef _WIN32
+static SECURITY_DESCRIPTOR mdb_null_sd;
+static SECURITY_ATTRIBUTES mdb_all_sa;
+static int mdb_sec_inited;
+#endif
+/** Return the library version info. */
char *
-mdb_version(int *maj, int *min, int *pat)
+mdb_version(int *major, int *minor, int *patch)
{
- *maj = MDB_VERSION_MAJOR;
- *min = MDB_VERSION_MINOR;
- *pat = MDB_VERSION_PATCH;
+ if (major) *major = MDB_VERSION_MAJOR;
+ if (minor) *minor = MDB_VERSION_MINOR;
+ if (patch) *patch = MDB_VERSION_PATCH;
return MDB_VERSION_STRING;
}
-static const char *errstr[] = {
+/** Table of descriptions for MDB @ref errors */
+static char *const mdb_errstr[] = {
"MDB_KEYEXIST: Key/data pair already exists",
"MDB_NOTFOUND: No matching key/data pair found",
"MDB_PAGE_NOTFOUND: Requested page not found",
return ("Successful return: 0");
if (err >= MDB_KEYEXIST && err <= MDB_VERSION_MISMATCH)
- return (char *)errstr[err - MDB_KEYEXIST];
+ return mdb_errstr[err - MDB_KEYEXIST];
return strerror(err);
}
+#if MDB_DEBUG
+/** Display a key in hexadecimal and return the address of the result.
+ * @param[in] key the key to display
+ * @param[in] buf the buffer to write into. Should always be #DKBUF.
+ * @return The key in hexadecimal form.
+ */
+char *
+mdb_dkey(MDB_val *key, char *buf)
+{
+ char *ptr = buf;
+ unsigned char *c = key->mv_data;
+ unsigned int i;
+ if (key->mv_size > MAXKEYSIZE)
+ return "MAXKEYSIZE";
+ /* may want to make this a dynamic check: if the key is mostly
+ * printable characters, print it as-is instead of converting to hex.
+ */
+#if 1
+ buf[0] = '\0';
+ for (i=0; i<key->mv_size; i++)
+ ptr += sprintf(ptr, "%02x", *c++);
+#else
+ sprintf(buf, "%.*s", key->mv_size, key->mv_data);
+#endif
+ return buf;
+}
+
+/** Display all the keys in the page. */
+static void
+mdb_page_keys(MDB_page *mp)
+{
+ MDB_node *node;
+ unsigned int i, nkeys;
+ MDB_val key;
+ DKBUF;
+
+ nkeys = NUMKEYS(mp);
+ DPRINTF("numkeys %d", nkeys);
+ for (i=0; i<nkeys; i++) {
+ node = NODEPTR(mp, i);
+ key.mv_size = node->mn_ksize;
+ key.mv_data = node->mn_data;
+ DPRINTF("key %d: %s", i, DKEY(&key));
+ }
+}
+#endif
+
+#if MDB_DEBUG > 2
+/** Count all the pages in each DB and in the freelist
+ * and make sure it matches the actual number of pages
+ * being used.
+ */
+static void mdb_audit(MDB_txn *txn)
+{
+ MDB_cursor mc;
+ MDB_val key, data;
+ int rc, i;
+ ID freecount, count;
+
+ freecount = 0;
+ mdb_cursor_init(&mc, txn, FREE_DBI, NULL);
+ while ((rc = mdb_cursor_get(&mc, &key, &data, MDB_NEXT)) == 0)
+ freecount += *(ID *)data.mv_data;
+ freecount += txn->mt_dbs[0].md_branch_pages + txn->mt_dbs[0].md_leaf_pages +
+ txn->mt_dbs[0].md_overflow_pages;
+
+ count = 0;
+ for (i = 0; i<txn->mt_numdbs; i++) {
+ count += txn->mt_dbs[i].md_branch_pages +
+ txn->mt_dbs[i].md_leaf_pages +
+ txn->mt_dbs[i].md_overflow_pages;
+ if (txn->mt_dbs[i].md_flags & MDB_DUPSORT) {
+ MDB_xcursor mx;
+ mdb_cursor_init(&mc, txn, i, &mx);
+ mdb_page_search(&mc, NULL, 0);
+ do {
+ int j;
+ MDB_page *mp;
+ mp = mc.mc_pg[mc.mc_top];
+ for (j=0; j<NUMKEYS(mp); j++) {
+ MDB_node *leaf = NODEPTR(mp, j);
+ if (leaf->mn_flags & F_SUBDATA) {
+ MDB_db db;
+ memcpy(&db, NODEDATA(leaf), sizeof(db));
+ count += db.md_branch_pages + db.md_leaf_pages +
+ db.md_overflow_pages;
+ }
+ }
+ }
+ while (mdb_cursor_sibling(&mc, 1) == 0);
+ }
+ }
+ assert(freecount + count + 2 >= txn->mt_next_pgno - 1);
+}
+#endif
+
int
mdb_cmp(MDB_txn *txn, MDB_dbi dbi, const MDB_val *a, const MDB_val *b)
{
return txn->mt_dbxs[dbi].md_cmp(a, b);
}
-static int
-_mdb_cmp(MDB_txn *txn, MDB_dbi dbi, const MDB_val *key1, const MDB_val *key2)
+int
+mdb_dcmp(MDB_txn *txn, MDB_dbi dbi, const MDB_val *a, const MDB_val *b)
{
- if (txn->mt_dbs[dbi].md_flags & (MDB_REVERSEKEY
-#if __BYTE_ORDER == __LITTLE_ENDIAN
- |MDB_INTEGERKEY
-#endif
- ))
- return memnrcmp(key1->mv_data, key1->mv_size, key2->mv_data, key2->mv_size);
+ if (txn->mt_dbxs[dbi].md_dcmp)
+ return txn->mt_dbxs[dbi].md_dcmp(a, b);
else
- return memncmp((char *)key1->mv_data, key1->mv_size, key2->mv_data, key2->mv_size);
+ return EINVAL; /* too bad you can't distinguish this from a valid result */
+}
+
+/** Allocate a single page.
+ * Re-use old malloc'd pages first, otherwise just malloc.
+ */
+static MDB_page *
+mdb_page_malloc(MDB_cursor *mc) {
+ MDB_page *ret;
+ size_t sz = mc->mc_txn->mt_env->me_psize;
+ if ((ret = mc->mc_txn->mt_env->me_dpages) != NULL) {
+ VGMEMP_ALLOC(mc->mc_txn->mt_env, ret, sz);
+ VGMEMP_DEFINED(ret, sizeof(ret->mp_next));
+ mc->mc_txn->mt_env->me_dpages = ret->mp_next;
+ } else if ((ret = malloc(sz)) != NULL) {
+ VGMEMP_ALLOC(mc->mc_txn->mt_env, ret, sz);
+ }
+ return ret;
}
-/* Allocate new page(s) for writing */
-static MDB_dpage *
-mdb_alloc_page(MDB_txn *txn, MDB_page *parent, unsigned int parent_idx, int num)
+/** Allocate pages for writing.
+ * If there are free pages available from older transactions, they
+ * will be re-used first. Otherwise a new page will be allocated.
+ * @param[in] mc cursor A cursor handle identifying the transaction and
+ * database for which we are allocating.
+ * @param[in] num the number of pages to allocate.
+ * @return Address of the allocated page(s). Requests for multiple pages
+ * will always be satisfied by a single contiguous chunk of memory.
+ */
+static MDB_page *
+mdb_page_alloc(MDB_cursor *mc, int num)
{
- MDB_dpage *dp;
+ MDB_txn *txn = mc->mc_txn;
+ MDB_page *np;
pgno_t pgno = P_INVALID;
- ULONG oldest;
- MIDL2 mid;
+ ID2 mid;
if (txn->mt_txnid > 2) {
- oldest = txn->mt_txnid - 2;
- if (!txn->mt_env->me_pghead && txn->mt_dbs[FREE_DBI].md_root != P_INVALID) {
- /* See if there's anything in the free DB */
- MDB_pageparent mpp;
- MDB_node *leaf;
- ULONG *kptr;
-
- mpp.mp_parent = NULL;
- mpp.mp_pi = 0;
- mdb_search_page(txn, FREE_DBI, NULL, NULL, 0, &mpp);
- leaf = NODEPTR(mpp.mp_page, 0);
- kptr = (ULONG *)NODEKEY(leaf);
-
- /* It's potentially usable, unless there are still
- * older readers outstanding. Grab it.
- */
- if (oldest > *kptr) {
- MDB_oldpages *mop;
+ if (!txn->mt_env->me_pghead &&
+ txn->mt_dbs[FREE_DBI].md_root != P_INVALID) {
+ /* See if there's anything in the free DB */
+ MDB_cursor m2;
+ MDB_node *leaf;
MDB_val data;
- pgno_t *idl;
-
- mdb_read_data(txn, leaf, &data);
- idl = (ULONG *)data.mv_data;
- mop = malloc(sizeof(MDB_oldpages) + MDB_IDL_SIZEOF(idl) - sizeof(pgno_t));
- mop->mo_next = txn->mt_env->me_pghead;
- mop->mo_txnid = *kptr;
- txn->mt_env->me_pghead = mop;
- memcpy(mop->mo_pages, idl, MDB_IDL_SIZEOF(idl));
+ txnid_t *kptr, oldest, last;
+
+ mdb_cursor_init(&m2, txn, FREE_DBI, NULL);
+ if (!txn->mt_env->me_pgfirst) {
+ mdb_page_search(&m2, NULL, 0);
+ leaf = NODEPTR(m2.mc_pg[m2.mc_top], 0);
+ kptr = (txnid_t *)NODEKEY(leaf);
+ last = *kptr;
+ } else {
+ MDB_val key;
+ int rc, exact;
+again:
+ exact = 0;
+ last = txn->mt_env->me_pglast + 1;
+ leaf = NULL;
+ key.mv_data = &last;
+ key.mv_size = sizeof(last);
+ rc = mdb_cursor_set(&m2, &key, &data, MDB_SET, &exact);
+ if (rc)
+ goto none;
+ last = *(txnid_t *)key.mv_data;
+ }
-#if DEBUG > 1
{
unsigned int i;
- DPRINTF("IDL read txn %lu root %lu num %lu",
- mop->mo_txnid, txn->mt_dbs[FREE_DBI].md_root, idl[0]);
- for (i=0; i<idl[0]; i++) {
- DPRINTF("IDL %lu", idl[i+1]);
+ oldest = txn->mt_txnid - 1;
+ for (i=0; i<txn->mt_env->me_txns->mti_numreaders; i++) {
+ txnid_t mr = txn->mt_env->me_txns->mti_readers[i].mr_txnid;
+ if (mr && mr < oldest)
+ oldest = mr;
}
}
+
+ if (oldest > last) {
+ /* It's usable, grab it.
+ */
+ MDB_oldpages *mop;
+ pgno_t *idl;
+
+ if (!txn->mt_env->me_pgfirst) {
+ mdb_node_read(txn, leaf, &data);
+ }
+ txn->mt_env->me_pglast = last;
+ if (!txn->mt_env->me_pgfirst)
+ txn->mt_env->me_pgfirst = last;
+ idl = (ID *) data.mv_data;
+ /* We might have a zero-length IDL due to freelist growth
+ * during a prior commit
+ */
+ if (!idl[0]) goto again;
+ mop = malloc(sizeof(MDB_oldpages) + MDB_IDL_SIZEOF(idl) - sizeof(pgno_t));
+ mop->mo_next = txn->mt_env->me_pghead;
+ mop->mo_txnid = last;
+ txn->mt_env->me_pghead = mop;
+ memcpy(mop->mo_pages, idl, MDB_IDL_SIZEOF(idl));
+
+#if MDB_DEBUG > 1
+ {
+ unsigned int i;
+ DPRINTF("IDL read txn %zu root %zu num %zu",
+ mop->mo_txnid, txn->mt_dbs[FREE_DBI].md_root, idl[0]);
+ for (i=0; i<idl[0]; i++) {
+ DPRINTF("IDL %zu", idl[i+1]);
+ }
+ }
#endif
- /* drop this IDL from the DB */
- mpp.mp_parent = NULL;
- mpp.mp_pi = 0;
- mdb_search_page(txn, FREE_DBI, NULL, NULL, 1, &mpp);
- leaf = NODEPTR(mpp.mp_page, 0);
- mdb_del0(txn, FREE_DBI, 0, &mpp, leaf);
- }
- }
- if (txn->mt_env->me_pghead) {
- unsigned int i;
- for (i=0; i<txn->mt_env->me_txns->mti_numreaders; i++) {
- ULONG mr = txn->mt_env->me_txns->mti_readers[i].mr_txnid;
- if (!mr) continue;
- if (mr < oldest)
- oldest = txn->mt_env->me_txns->mti_readers[i].mr_txnid;
+ }
}
- if (oldest > txn->mt_env->me_pghead->mo_txnid) {
+none:
+ if (txn->mt_env->me_pghead) {
MDB_oldpages *mop = txn->mt_env->me_pghead;
- txn->mt_oldest = oldest;
if (num > 1) {
/* FIXME: For now, always use fresh pages. We
* really ought to search the free list for a
}
}
}
- }
if (pgno == P_INVALID) {
/* DB size is maxed out */
- if (txn->mt_next_pgno + num >= txn->mt_env->me_maxpg)
+ if (txn->mt_next_pgno + num >= txn->mt_env->me_maxpg) {
+ DPUTS("DB size maxed out");
return NULL;
+ }
+ }
+ if (txn->mt_env->me_dpages && num == 1) {
+ np = txn->mt_env->me_dpages;
+ VGMEMP_ALLOC(txn->mt_env, np, txn->mt_env->me_psize);
+ VGMEMP_DEFINED(np, sizeof(np->mp_next));
+ txn->mt_env->me_dpages = np->mp_next;
+ } else {
+ size_t sz = txn->mt_env->me_psize * num;
+ if ((np = malloc(sz)) == NULL)
+ return NULL;
+ VGMEMP_ALLOC(txn->mt_env, np, sz);
}
- if ((dp = malloc(txn->mt_env->me_psize * num + sizeof(MDB_dhead))) == NULL)
- return NULL;
- dp->h.md_num = num;
- dp->h.md_parent = parent;
- dp->h.md_pi = parent_idx;
if (pgno == P_INVALID) {
- dp->p.mp_pgno = txn->mt_next_pgno;
+ np->mp_pgno = txn->mt_next_pgno;
txn->mt_next_pgno += num;
} else {
- dp->p.mp_pgno = pgno;
+ np->mp_pgno = pgno;
}
- mid.mid = dp->p.mp_pgno;
- mid.mptr = dp;
- mdb_midl2_insert(txn->mt_u.dirty_list, &mid);
+ mid.mid = np->mp_pgno;
+ mid.mptr = np;
+ mdb_mid2l_insert(txn->mt_u.dirty_list, &mid);
- return dp;
+ return np;
}
-/* Touch a page: make it dirty and re-insert into tree with updated pgno.
+/** Touch a page: make it dirty and re-insert into tree with updated pgno.
+ * @param[in] mc cursor pointing to the page to be touched
+ * @return 0 on success, non-zero on failure.
*/
static int
-mdb_touch(MDB_txn *txn, MDB_pageparent *pp)
+mdb_page_touch(MDB_cursor *mc)
{
- MDB_page *mp = pp->mp_page;
+ MDB_page *mp = mc->mc_pg[mc->mc_top];
pgno_t pgno;
- assert(txn != NULL);
- assert(pp != NULL);
if (!F_ISSET(mp->mp_flags, P_DIRTY)) {
- MDB_dpage *dp;
- if ((dp = mdb_alloc_page(txn, pp->mp_parent, pp->mp_pi, 1)) == NULL)
+ MDB_page *np;
+ if ((np = mdb_page_alloc(mc, 1)) == NULL)
return ENOMEM;
- DPRINTF("touched page %lu -> %lu", mp->mp_pgno, dp->p.mp_pgno);
- mdb_midl_insert(txn->mt_free_pgs, mp->mp_pgno);
- pgno = dp->p.mp_pgno;
- memcpy(&dp->p, mp, txn->mt_env->me_psize);
- mp = &dp->p;
+ DPRINTF("touched db %u page %zu -> %zu", mc->mc_dbi, mp->mp_pgno, np->mp_pgno);
+ assert(mp->mp_pgno != np->mp_pgno);
+ mdb_midl_append(&mc->mc_txn->mt_free_pgs, mp->mp_pgno);
+ pgno = np->mp_pgno;
+ memcpy(np, mp, mc->mc_txn->mt_env->me_psize);
+ mp = np;
mp->mp_pgno = pgno;
mp->mp_flags |= P_DIRTY;
- /* Update the page number to new touched page. */
- if (pp->mp_parent != NULL)
- NODEPGNO(NODEPTR(pp->mp_parent, pp->mp_pi)) = mp->mp_pgno;
- pp->mp_page = mp;
+finish:
+ /* Adjust other cursors pointing to mp */
+ if (mc->mc_flags & C_SUB) {
+ MDB_cursor *m2, *m3;
+ MDB_dbi dbi = mc->mc_dbi-1;
+
+ for (m2 = mc->mc_txn->mt_cursors[dbi]; m2; m2=m2->mc_next) {
+ if (m2 == mc) continue;
+ m3 = &m2->mc_xcursor->mx_cursor;
+ if (m3->mc_snum < mc->mc_snum) continue;
+ if (m3->mc_pg[mc->mc_top] == mc->mc_pg[mc->mc_top]) {
+ m3->mc_pg[mc->mc_top] = mp;
+ }
+ }
+ } else {
+ MDB_cursor *m2;
+
+ for (m2 = mc->mc_txn->mt_cursors[mc->mc_dbi]; m2; m2=m2->mc_next) {
+ if (m2 == mc || m2->mc_snum < mc->mc_snum) continue;
+ if (m2->mc_pg[mc->mc_top] == mc->mc_pg[mc->mc_top]) {
+ m2->mc_pg[mc->mc_top] = mp;
+ }
+ }
+ }
+ mc->mc_pg[mc->mc_top] = mp;
+ /** If this page has a parent, update the parent to point to
+ * this new page.
+ */
+ if (mc->mc_top)
+ SETPGNO(NODEPTR(mc->mc_pg[mc->mc_top-1], mc->mc_ki[mc->mc_top-1]), mp->mp_pgno);
+ else
+ mc->mc_db->md_root = mp->mp_pgno;
+ } else if (mc->mc_txn->mt_parent) {
+ MDB_page *np;
+ ID2 mid;
+ /* If txn has a parent, make sure the page is in our
+ * dirty list.
+ */
+ if (mc->mc_txn->mt_u.dirty_list[0].mid) {
+ unsigned x = mdb_mid2l_search(mc->mc_txn->mt_u.dirty_list, mp->mp_pgno);
+ if (x <= mc->mc_txn->mt_u.dirty_list[0].mid &&
+ mc->mc_txn->mt_u.dirty_list[x].mid == mp->mp_pgno) {
+ if (mc->mc_txn->mt_u.dirty_list[x].mptr != mp) {
+ mp = mc->mc_txn->mt_u.dirty_list[x].mptr;
+ mc->mc_pg[mc->mc_top] = mp;
+ }
+ return 0;
+ }
+ }
+ /* No - copy it */
+ np = mdb_page_malloc(mc);
+ memcpy(np, mp, mc->mc_txn->mt_env->me_psize);
+ mid.mid = np->mp_pgno;
+ mid.mptr = np;
+ mdb_mid2l_insert(mc->mc_txn->mt_u.dirty_list, &mid);
+ mp = np;
+ goto finish;
}
return 0;
}
{
int rc = 0;
if (force || !F_ISSET(env->me_flags, MDB_NOSYNC)) {
- if (fdatasync(env->me_fd))
- rc = errno;
+ if (MDB_FDATASYNC(env->me_fd))
+ rc = ErrCode();
}
return rc;
}
-int
-mdb_txn_begin(MDB_env *env, int rdonly, MDB_txn **ret)
+/** Make shadow copies of all of parent txn's cursors */
+static int
+mdb_cursor_shadow(MDB_txn *src, MDB_txn *dst)
{
- MDB_txn *txn;
- int rc, toggle;
-
- if (env->me_flags & MDB_FATAL_ERROR) {
- DPRINTF("mdb_txn_begin: environment had fatal error, must shutdown!");
- return MDB_PANIC;
+ MDB_cursor *mc, *m2;
+ unsigned int i, j, size;
+
+ for (i=0;i<src->mt_numdbs; i++) {
+ if (src->mt_cursors[i]) {
+ size = sizeof(MDB_cursor);
+ if (src->mt_cursors[i]->mc_xcursor)
+ size += sizeof(MDB_xcursor);
+ for (m2 = src->mt_cursors[i]; m2; m2=m2->mc_next) {
+ mc = malloc(size);
+ if (!mc)
+ return ENOMEM;
+ mc->mc_orig = m2;
+ mc->mc_txn = dst;
+ mc->mc_dbi = i;
+ mc->mc_db = &dst->mt_dbs[i];
+ mc->mc_dbx = m2->mc_dbx;
+ mc->mc_dbflag = &dst->mt_dbflags[i];
+ mc->mc_snum = m2->mc_snum;
+ mc->mc_top = m2->mc_top;
+ mc->mc_flags = m2->mc_flags | C_SHADOW;
+ for (j=0; j<mc->mc_snum; j++) {
+ mc->mc_pg[j] = m2->mc_pg[j];
+ mc->mc_ki[j] = m2->mc_ki[j];
+ }
+ if (m2->mc_xcursor) {
+ MDB_xcursor *mx, *mx2;
+ mx = (MDB_xcursor *)(mc+1);
+ mc->mc_xcursor = mx;
+ mx2 = m2->mc_xcursor;
+ mx->mx_db = mx2->mx_db;
+ mx->mx_dbx = mx2->mx_dbx;
+ mx->mx_dbflag = mx2->mx_dbflag;
+ mx->mx_cursor.mc_txn = dst;
+ mx->mx_cursor.mc_dbi = mx2->mx_cursor.mc_dbi;
+ mx->mx_cursor.mc_db = &mx->mx_db;
+ mx->mx_cursor.mc_dbx = &mx->mx_dbx;
+ mx->mx_cursor.mc_dbflag = &mx->mx_dbflag;
+ mx->mx_cursor.mc_snum = mx2->mx_cursor.mc_snum;
+ mx->mx_cursor.mc_top = mx2->mx_cursor.mc_top;
+ mx->mx_cursor.mc_flags = mx2->mx_cursor.mc_flags | C_SHADOW;
+ for (j=0; j<mx2->mx_cursor.mc_snum; j++) {
+ mx->mx_cursor.mc_pg[j] = mx2->mx_cursor.mc_pg[j];
+ mx->mx_cursor.mc_ki[j] = mx2->mx_cursor.mc_ki[j];
+ }
+ } else {
+ mc->mc_xcursor = NULL;
+ }
+ mc->mc_next = dst->mt_cursors[i];
+ dst->mt_cursors[i] = mc;
+ }
+ }
}
- if ((txn = calloc(1, sizeof(MDB_txn))) == NULL) {
- DPRINTF("calloc: %s", strerror(errno));
- return ENOMEM;
+ return MDB_SUCCESS;
+}
+
+/** Merge shadow cursors back into parent's */
+static void
+mdb_cursor_merge(MDB_txn *txn)
+{
+ MDB_dbi i;
+ for (i=0; i<txn->mt_numdbs; i++) {
+ if (txn->mt_cursors[i]) {
+ MDB_cursor *mc;
+ while ((mc = txn->mt_cursors[i])) {
+ txn->mt_cursors[i] = mc->mc_next;
+ if (mc->mc_flags & C_SHADOW) {
+ MDB_cursor *m2 = mc->mc_orig;
+ unsigned int j;
+ m2->mc_snum = mc->mc_snum;
+ m2->mc_top = mc->mc_top;
+ for (j=0; j<mc->mc_snum; j++) {
+ m2->mc_pg[j] = mc->mc_pg[j];
+ m2->mc_ki[j] = mc->mc_ki[j];
+ }
+ }
+ if (mc->mc_flags & C_ALLOCD)
+ free(mc);
+ }
+ }
}
+}
- if (rdonly) {
- txn->mt_flags |= MDB_TXN_RDONLY;
- } else {
- txn->mt_u.dirty_list = env->me_dirty_list;
- txn->mt_u.dirty_list[0].mid = 0;
- txn->mt_free_pgs = env->me_free_pgs;
- txn->mt_free_pgs[0] = 0;
+static void
+mdb_txn_reset0(MDB_txn *txn);
- pthread_mutex_lock(&env->me_txns->mti_wmutex);
- env->me_txns->mti_txnid++;
- }
+/** Common code for #mdb_txn_begin() and #mdb_txn_renew().
+ * @param[in] txn the transaction handle to initialize
+ * @return 0 on success, non-zero on failure. This can only
+ * fail for read-only transactions, and then only if the
+ * reader table is full.
+ */
+static int
+mdb_txn_renew0(MDB_txn *txn)
+{
+ MDB_env *env = txn->mt_env;
+ char mt_dbflag = 0;
- txn->mt_txnid = env->me_txns->mti_txnid;
- if (rdonly) {
+ if (txn->mt_flags & MDB_TXN_RDONLY) {
MDB_reader *r = pthread_getspecific(env->me_txkey);
if (!r) {
unsigned int i;
- pthread_mutex_lock(&env->me_txns->mti_mutex);
+ pid_t pid = getpid();
+ pthread_t tid = pthread_self();
+
+ LOCK_MUTEX_R(env);
for (i=0; i<env->me_txns->mti_numreaders; i++)
if (env->me_txns->mti_readers[i].mr_pid == 0)
break;
if (i == env->me_maxreaders) {
- pthread_mutex_unlock(&env->me_txns->mti_mutex);
- return ENOSPC;
+ UNLOCK_MUTEX_R(env);
+ return ENOMEM;
}
- env->me_txns->mti_readers[i].mr_pid = getpid();
- env->me_txns->mti_readers[i].mr_tid = pthread_self();
- r = &env->me_txns->mti_readers[i];
- pthread_setspecific(env->me_txkey, r);
+ env->me_txns->mti_readers[i].mr_pid = pid;
+ env->me_txns->mti_readers[i].mr_tid = tid;
if (i >= env->me_txns->mti_numreaders)
env->me_txns->mti_numreaders = i+1;
- pthread_mutex_unlock(&env->me_txns->mti_mutex);
+ UNLOCK_MUTEX_R(env);
+ r = &env->me_txns->mti_readers[i];
+ pthread_setspecific(env->me_txkey, r);
}
+ txn->mt_toggle = env->me_txns->mti_me_toggle;
+ txn->mt_txnid = env->me_txns->mti_txnid;
+ /* This happens if a different process was the
+ * last writer to the DB.
+ */
+ if (env->me_wtxnid < txn->mt_txnid)
+ mt_dbflag = DB_STALE;
r->mr_txnid = txn->mt_txnid;
txn->mt_u.reader = r;
} else {
- env->me_txn = txn;
- }
+ LOCK_MUTEX_W(env);
- txn->mt_env = env;
-
- toggle = env->me_txns->mti_me_toggle;
- if ((rc = mdb_env_read_meta(env, &toggle)) != MDB_SUCCESS) {
- mdb_txn_abort(txn);
- return rc;
+ txn->mt_txnid = env->me_txns->mti_txnid;
+ if (env->me_wtxnid < txn->mt_txnid)
+ mt_dbflag = DB_STALE;
+ txn->mt_txnid++;
+ txn->mt_toggle = env->me_txns->mti_me_toggle;
+ txn->mt_u.dirty_list = env->me_dirty_list;
+ txn->mt_u.dirty_list[0].mid = 0;
+ txn->mt_free_pgs = env->me_free_pgs;
+ txn->mt_free_pgs[0] = 0;
+ txn->mt_next_pgno = env->me_metas[txn->mt_toggle]->mm_last_pg+1;
+ env->me_txn = txn;
}
/* Copy the DB arrays */
+ LAZY_RWLOCK_RDLOCK(&env->me_dblock);
txn->mt_numdbs = env->me_numdbs;
txn->mt_dbxs = env->me_dbxs; /* mostly static anyway */
- txn->mt_dbs = malloc(env->me_maxdbs * sizeof(MDB_db));
- memcpy(txn->mt_dbs, env->me_meta->mm_dbs, 2 * sizeof(MDB_db));
+ memcpy(txn->mt_dbs, env->me_metas[txn->mt_toggle]->mm_dbs, 2 * sizeof(MDB_db));
if (txn->mt_numdbs > 2)
memcpy(txn->mt_dbs+2, env->me_dbs[env->me_db_toggle]+2,
(txn->mt_numdbs - 2) * sizeof(MDB_db));
+ LAZY_RWLOCK_UNLOCK(&env->me_dblock);
- if (!rdonly) {
- if (toggle)
- txn->mt_flags |= MDB_TXN_METOGGLE;
- txn->mt_next_pgno = env->me_meta->mm_last_pg+1;
- }
-
- DPRINTF("begin transaction %lu on mdbenv %p, root page %lu",
- txn->mt_txnid, (void *) env, txn->mt_dbs[MAIN_DBI].md_root);
+ memset(txn->mt_dbflags, mt_dbflag, env->me_numdbs);
- *ret = txn;
return MDB_SUCCESS;
}
-void
-mdb_txn_abort(MDB_txn *txn)
+int
+mdb_txn_renew(MDB_txn *txn)
{
- MDB_env *env;
+ int rc;
- if (txn == NULL)
- return;
+ if (!txn)
+ return EINVAL;
- env = txn->mt_env;
- DPRINTF("abort transaction %lu on mdbenv %p, root page %lu",
- txn->mt_txnid, (void *) env, txn->mt_dbs[MAIN_DBI].md_root);
+ if (txn->mt_env->me_flags & MDB_FATAL_ERROR) {
+ DPUTS("environment had fatal error, must shutdown!");
+ return MDB_PANIC;
+ }
+
+ rc = mdb_txn_renew0(txn);
+ if (rc == MDB_SUCCESS) {
+ DPRINTF("renew txn %zu%c %p on mdbenv %p, root page %zu",
+ txn->mt_txnid, (txn->mt_flags & MDB_TXN_RDONLY) ? 'r' : 'w',
+ (void *)txn, (void *)txn->mt_env, txn->mt_dbs[MAIN_DBI].md_root);
+ }
+ return rc;
+}
+
+int
+mdb_txn_begin(MDB_env *env, MDB_txn *parent, unsigned int flags, MDB_txn **ret)
+{
+ MDB_txn *txn;
+ int rc, size;
+
+ if (env->me_flags & MDB_FATAL_ERROR) {
+ DPUTS("environment had fatal error, must shutdown!");
+ return MDB_PANIC;
+ }
+ if (parent) {
+ /* parent already has an active child txn */
+ if (parent->mt_child) {
+ return EINVAL;
+ }
+ }
+ size = sizeof(MDB_txn) + env->me_maxdbs * (sizeof(MDB_db)+1);
+ if (!(flags & MDB_RDONLY))
+ size += env->me_maxdbs * sizeof(MDB_cursor *);
+
+ if ((txn = calloc(1, size)) == NULL) {
+ DPRINTF("calloc: %s", strerror(ErrCode()));
+ return ENOMEM;
+ }
+ txn->mt_dbs = (MDB_db *)(txn+1);
+ if (flags & MDB_RDONLY) {
+ txn->mt_flags |= MDB_TXN_RDONLY;
+ txn->mt_dbflags = (unsigned char *)(txn->mt_dbs + env->me_maxdbs);
+ } else {
+ txn->mt_cursors = (MDB_cursor **)(txn->mt_dbs + env->me_maxdbs);
+ txn->mt_dbflags = (unsigned char *)(txn->mt_cursors + env->me_maxdbs);
+ }
+ txn->mt_env = env;
+
+ if (parent) {
+ txn->mt_free_pgs = mdb_midl_alloc();
+ if (!txn->mt_free_pgs) {
+ free(txn);
+ return ENOMEM;
+ }
+ txn->mt_u.dirty_list = malloc(sizeof(ID2)*MDB_IDL_UM_SIZE);
+ if (!txn->mt_u.dirty_list) {
+ free(txn->mt_free_pgs);
+ free(txn);
+ return ENOMEM;
+ }
+ txn->mt_txnid = parent->mt_txnid;
+ txn->mt_toggle = parent->mt_toggle;
+ txn->mt_u.dirty_list[0].mid = 0;
+ txn->mt_free_pgs[0] = 0;
+ txn->mt_next_pgno = parent->mt_next_pgno;
+ parent->mt_child = txn;
+ txn->mt_parent = parent;
+ txn->mt_numdbs = parent->mt_numdbs;
+ txn->mt_dbxs = parent->mt_dbxs;
+ memcpy(txn->mt_dbs, parent->mt_dbs, txn->mt_numdbs * sizeof(MDB_db));
+ memcpy(txn->mt_dbflags, parent->mt_dbflags, txn->mt_numdbs);
+ mdb_cursor_shadow(parent, txn);
+ rc = 0;
+ } else {
+ rc = mdb_txn_renew0(txn);
+ }
+ if (rc)
+ free(txn);
+ else {
+ *ret = txn;
+ DPRINTF("begin txn %zu%c %p on mdbenv %p, root page %zu",
+ txn->mt_txnid, (txn->mt_flags & MDB_TXN_RDONLY) ? 'r' : 'w',
+ (void *) txn, (void *) env, txn->mt_dbs[MAIN_DBI].md_root);
+ }
+
+ return rc;
+}
- free(txn->mt_dbs);
+/** Common code for #mdb_txn_reset() and #mdb_txn_abort().
+ * @param[in] txn the transaction handle to reset
+ */
+static void
+mdb_txn_reset0(MDB_txn *txn)
+{
+ MDB_env *env = txn->mt_env;
if (F_ISSET(txn->mt_flags, MDB_TXN_RDONLY)) {
txn->mt_u.reader->mr_txnid = 0;
} else {
MDB_oldpages *mop;
+ MDB_page *dp;
unsigned int i;
- /* Discard all dirty pages. */
- for (i=1; i<=txn->mt_u.dirty_list[0].mid; i++)
- free(txn->mt_u.dirty_list[i].mptr);
+ /* close(free) all cursors */
+ for (i=0; i<txn->mt_numdbs; i++) {
+ if (txn->mt_cursors[i]) {
+ MDB_cursor *mc;
+ while ((mc = txn->mt_cursors[i])) {
+ txn->mt_cursors[i] = mc->mc_next;
+ if (mc->mc_flags & C_ALLOCD)
+ free(mc);
+ }
+ }
+ }
+
+ /* return all dirty pages to dpage list */
+ for (i=1; i<=txn->mt_u.dirty_list[0].mid; i++) {
+ dp = txn->mt_u.dirty_list[i].mptr;
+ if (!IS_OVERFLOW(dp) || dp->mp_pages == 1) {
+ dp->mp_next = txn->mt_env->me_dpages;
+ VGMEMP_FREE(txn->mt_env, dp);
+ txn->mt_env->me_dpages = dp;
+ } else {
+ /* large pages just get freed directly */
+ VGMEMP_FREE(txn->mt_env, dp);
+ free(dp);
+ }
+ }
+
+ if (txn->mt_parent) {
+ txn->mt_parent->mt_child = NULL;
+ free(txn->mt_free_pgs);
+ free(txn->mt_u.dirty_list);
+ return;
+ } else {
+ if (mdb_midl_shrink(&txn->mt_free_pgs))
+ env->me_free_pgs = txn->mt_free_pgs;
+ }
while ((mop = txn->mt_env->me_pghead)) {
txn->mt_env->me_pghead = mop->mo_next;
free(mop);
}
+ txn->mt_env->me_pgfirst = 0;
+ txn->mt_env->me_pglast = 0;
env->me_txn = NULL;
- env->me_txns->mti_txnid--;
- for (i=2; i<env->me_numdbs; i++)
- env->me_dbxs[i].md_dirty = 0;
- pthread_mutex_unlock(&env->me_txns->mti_wmutex);
+ /* The writer mutex was locked in mdb_txn_begin. */
+ UNLOCK_MUTEX_W(env);
}
+}
+
+void
+mdb_txn_reset(MDB_txn *txn)
+{
+ if (txn == NULL)
+ return;
+
+ DPRINTF("reset txn %zu%c %p on mdbenv %p, root page %zu",
+ txn->mt_txnid, (txn->mt_flags & MDB_TXN_RDONLY) ? 'r' : 'w',
+ (void *) txn, (void *)txn->mt_env, txn->mt_dbs[MAIN_DBI].md_root);
+
+ mdb_txn_reset0(txn);
+}
+
+void
+mdb_txn_abort(MDB_txn *txn)
+{
+ if (txn == NULL)
+ return;
+ DPRINTF("abort txn %zu%c %p on mdbenv %p, root page %zu",
+ txn->mt_txnid, (txn->mt_flags & MDB_TXN_RDONLY) ? 'r' : 'w',
+ (void *)txn, (void *)txn->mt_env, txn->mt_dbs[MAIN_DBI].md_root);
+
+ if (txn->mt_child)
+ mdb_txn_abort(txn->mt_child);
+
+ mdb_txn_reset0(txn);
free(txn);
}
unsigned int i;
ssize_t rc;
off_t size;
- MDB_dpage *dp;
+ MDB_page *dp;
MDB_env *env;
- pgno_t next;
- struct iovec iov[MDB_COMMIT_PAGES];
+ pgno_t next, freecnt;
+ MDB_cursor mc;
assert(txn != NULL);
assert(txn->mt_env != NULL);
+ if (txn->mt_child) {
+ mdb_txn_commit(txn->mt_child);
+ txn->mt_child = NULL;
+ }
+
env = txn->mt_env;
if (F_ISSET(txn->mt_flags, MDB_TXN_RDONLY)) {
+ if (txn->mt_numdbs > env->me_numdbs) {
+ /* update the DB tables */
+ int toggle = !env->me_db_toggle;
+ MDB_db *ip, *jp;
+ MDB_dbi i;
+
+ ip = &env->me_dbs[toggle][env->me_numdbs];
+ jp = &txn->mt_dbs[env->me_numdbs];
+ LAZY_RWLOCK_WRLOCK(&env->me_dblock);
+ for (i = env->me_numdbs; i < txn->mt_numdbs; i++) {
+ *ip++ = *jp++;
+ }
+
+ env->me_db_toggle = toggle;
+ env->me_numdbs = txn->mt_numdbs;
+ LAZY_RWLOCK_UNLOCK(&env->me_dblock);
+ }
mdb_txn_abort(txn);
return MDB_SUCCESS;
}
- if (txn != env->me_txn) {
- DPRINTF("attempt to commit unknown transaction");
+ if (F_ISSET(txn->mt_flags, MDB_TXN_ERROR)) {
+ DPUTS("error flag is set, can't commit");
+ if (txn->mt_parent)
+ txn->mt_parent->mt_flags |= MDB_TXN_ERROR;
mdb_txn_abort(txn);
return EINVAL;
}
- if (F_ISSET(txn->mt_flags, MDB_TXN_ERROR)) {
- DPRINTF("error flag is set, can't commit");
+ /* Merge (and close) our cursors with parent's */
+ mdb_cursor_merge(txn);
+
+ if (txn->mt_parent) {
+ MDB_db *ip, *jp;
+ MDB_dbi i;
+ unsigned x, y;
+ ID2L dst, src;
+
+ /* Update parent's DB table */
+ ip = &txn->mt_parent->mt_dbs[2];
+ jp = &txn->mt_dbs[2];
+ for (i = 2; i < txn->mt_numdbs; i++) {
+ if (ip->md_root != jp->md_root)
+ *ip = *jp;
+ ip++; jp++;
+ }
+ txn->mt_parent->mt_numdbs = txn->mt_numdbs;
+
+ /* Append our free list to parent's */
+ mdb_midl_append_list(&txn->mt_parent->mt_free_pgs,
+ txn->mt_free_pgs);
+ mdb_midl_free(txn->mt_free_pgs);
+
+ /* Merge our dirty list with parent's */
+ dst = txn->mt_parent->mt_u.dirty_list;
+ src = txn->mt_u.dirty_list;
+ x = mdb_mid2l_search(dst, src[1].mid);
+ for (y=1; y<=src[0].mid; y++) {
+ while (x <= dst[0].mid && dst[x].mid != src[y].mid) x++;
+ if (x > dst[0].mid)
+ break;
+ free(dst[x].mptr);
+ dst[x].mptr = src[y].mptr;
+ }
+ x = dst[0].mid;
+ for (; y<=src[0].mid; y++) {
+ if (++x >= MDB_IDL_UM_MAX) {
+ mdb_txn_abort(txn);
+ return ENOMEM;
+ }
+ dst[x] = src[y];
+ }
+ dst[0].mid = x;
+ free(txn->mt_u.dirty_list);
+ txn->mt_parent->mt_child = NULL;
+ free(txn);
+ return MDB_SUCCESS;
+ }
+
+ if (txn != env->me_txn) {
+ DPUTS("attempt to commit unknown transaction");
mdb_txn_abort(txn);
return EINVAL;
}
if (!txn->mt_u.dirty_list[0].mid)
goto done;
- DPRINTF("committing transaction %lu on mdbenv %p, root page %lu",
- txn->mt_txnid, (void *) env, txn->mt_dbs[MAIN_DBI].md_root);
+ DPRINTF("committing txn %zu %p on mdbenv %p, root page %zu",
+ txn->mt_txnid, (void *)txn, (void *)env, txn->mt_dbs[MAIN_DBI].md_root);
+
+ mdb_cursor_init(&mc, txn, FREE_DBI, NULL);
/* should only be one record now */
if (env->me_pghead) {
- MDB_val key, data;
- MDB_oldpages *mop;
+ /* make sure first page of freeDB is touched and on freelist */
+ mdb_page_search(&mc, NULL, 1);
+ }
- mop = env->me_pghead;
- key.mv_size = sizeof(pgno_t);
- key.mv_data = (char *)&mop->mo_txnid;
- data.mv_size = MDB_IDL_SIZEOF(mop->mo_pages);
- data.mv_data = mop->mo_pages;
- mdb_put0(txn, FREE_DBI, &key, &data, 0);
- free(env->me_pghead);
- env->me_pghead = NULL;
+ /* Delete IDLs we used from the free list */
+ if (env->me_pgfirst) {
+ txnid_t cur;
+ MDB_val key;
+ int exact = 0;
+
+ key.mv_size = sizeof(cur);
+ for (cur = env->me_pgfirst; cur <= env->me_pglast; cur++) {
+ key.mv_data = &cur;
+
+ mdb_cursor_set(&mc, &key, NULL, MDB_SET, &exact);
+ mdb_cursor_del(&mc, 0);
+ }
+ env->me_pgfirst = 0;
+ env->me_pglast = 0;
}
+
/* save to free list */
+free2:
+ freecnt = txn->mt_free_pgs[0];
if (!MDB_IDL_IS_ZERO(txn->mt_free_pgs)) {
MDB_val key, data;
- MDB_pageparent mpp;
/* make sure last page of freeDB is touched and on freelist */
key.mv_size = MAXKEYSIZE+1;
key.mv_data = NULL;
- mpp.mp_parent = NULL;
- mpp.mp_pi = 0;
- mdb_search_page(txn, FREE_DBI, &key, NULL, 1, &mpp);
+ mdb_page_search(&mc, &key, 1);
-#if DEBUG > 1
+ mdb_midl_sort(txn->mt_free_pgs);
+#if MDB_DEBUG > 1
{
unsigned int i;
- ULONG *idl = txn->mt_free_pgs;
- DPRINTF("IDL write txn %lu root %lu num %lu",
+ ID *idl = txn->mt_free_pgs;
+ DPRINTF("IDL write txn %zu root %zu num %zu",
txn->mt_txnid, txn->mt_dbs[FREE_DBI].md_root, idl[0]);
for (i=0; i<idl[0]; i++) {
- DPRINTF("IDL %lu", idl[i+1]);
+ DPRINTF("IDL %zu", idl[i+1]);
}
}
#endif
/* write to last page of freeDB */
key.mv_size = sizeof(pgno_t);
- key.mv_data = (char *)&txn->mt_txnid;
- data.mv_size = MDB_IDL_SIZEOF(txn->mt_free_pgs);
+ key.mv_data = &txn->mt_txnid;
data.mv_data = txn->mt_free_pgs;
- mdb_put0(txn, FREE_DBI, &key, &data, 0);
+ /* The free list can still grow during this call,
+ * despite the pre-emptive touches above. So check
+ * and make sure the entire thing got written.
+ */
+ do {
+ freecnt = txn->mt_free_pgs[0];
+ data.mv_size = MDB_IDL_SIZEOF(txn->mt_free_pgs);
+ rc = mdb_cursor_put(&mc, &key, &data, 0);
+ if (rc) {
+ mdb_txn_abort(txn);
+ return rc;
+ }
+ } while (freecnt != txn->mt_free_pgs[0]);
+ }
+ /* should only be one record now */
+again:
+ if (env->me_pghead) {
+ MDB_val key, data;
+ MDB_oldpages *mop;
+ pgno_t orig;
+ txnid_t id;
+
+ mop = env->me_pghead;
+ id = mop->mo_txnid;
+ key.mv_size = sizeof(id);
+ key.mv_data = &id;
+ data.mv_size = MDB_IDL_SIZEOF(mop->mo_pages);
+ data.mv_data = mop->mo_pages;
+ orig = mop->mo_pages[0];
+ /* These steps may grow the freelist again
+ * due to freed overflow pages...
+ */
+ mdb_cursor_put(&mc, &key, &data, 0);
+ if (mop == env->me_pghead && env->me_pghead->mo_txnid == id) {
+ /* could have been used again here */
+ if (mop->mo_pages[0] != orig) {
+ data.mv_size = MDB_IDL_SIZEOF(mop->mo_pages);
+ data.mv_data = mop->mo_pages;
+ id = mop->mo_txnid;
+ mdb_cursor_put(&mc, &key, &data, 0);
+ }
+ env->me_pghead = NULL;
+ free(mop);
+ } else {
+ /* was completely used up */
+ mdb_cursor_del(&mc, 0);
+ if (env->me_pghead)
+ goto again;
+ }
+ env->me_pgfirst = 0;
+ env->me_pglast = 0;
+ }
+ /* Check for growth of freelist again */
+ if (freecnt != txn->mt_free_pgs[0])
+ goto free2;
+
+ if (!MDB_IDL_IS_ZERO(txn->mt_free_pgs)) {
+ if (mdb_midl_shrink(&txn->mt_free_pgs))
+ env->me_free_pgs = txn->mt_free_pgs;
}
/* Update DB root pointers. Their pages have already been
* touched so this is all in-place and cannot fail.
*/
{
+ MDB_dbi i;
MDB_val data;
data.mv_size = sizeof(MDB_db);
+ mdb_cursor_init(&mc, txn, MAIN_DBI, NULL);
for (i = 2; i < txn->mt_numdbs; i++) {
- if (txn->mt_dbxs[i].md_dirty) {
+ if (txn->mt_dbflags[i] & DB_DIRTY) {
data.mv_data = &txn->mt_dbs[i];
- mdb_put0(txn, MAIN_DBI, &txn->mt_dbxs[i].md_name, &data, 0);
+ mdb_cursor_put(&mc, &txn->mt_dbxs[i].md_name, &data, 0);
}
}
}
+#if MDB_DEBUG > 2
+ mdb_audit(txn);
+#endif
/* Commit up to MDB_COMMIT_PAGES dirty pages to disk until done.
*/
next = 0;
+ i = 1;
do {
+#ifdef _WIN32
+ /* Windows actually supports scatter/gather I/O, but only on
+ * unbuffered file handles. Since we're relying on the OS page
+ * cache for all our data, that's self-defeating. So we just
+ * write pages one at a time. We use the ov structure to set
+ * the write offset, to at least save the overhead of a Seek
+ * system call.
+ */
+ OVERLAPPED ov;
+ memset(&ov, 0, sizeof(ov));
+ for (; i<=txn->mt_u.dirty_list[0].mid; i++) {
+ size_t wsize;
+ dp = txn->mt_u.dirty_list[i].mptr;
+ DPRINTF("committing page %zu", dp->mp_pgno);
+ size = dp->mp_pgno * env->me_psize;
+ ov.Offset = size & 0xffffffff;
+ ov.OffsetHigh = size >> 16;
+ ov.OffsetHigh >>= 16;
+ /* clear dirty flag */
+ dp->mp_flags &= ~P_DIRTY;
+ wsize = env->me_psize;
+ if (IS_OVERFLOW(dp)) wsize *= dp->mp_pages;
+ rc = WriteFile(env->me_fd, dp, wsize, NULL, &ov);
+ if (!rc) {
+ n = ErrCode();
+ DPRINTF("WriteFile: %d", n);
+ mdb_txn_abort(txn);
+ return n;
+ }
+ }
+ done = 1;
+#else
+ struct iovec iov[MDB_COMMIT_PAGES];
n = 0;
done = 1;
size = 0;
- for (i=1; i<=txn->mt_u.dirty_list[0].mid; i++) {
+ for (; i<=txn->mt_u.dirty_list[0].mid; i++) {
dp = txn->mt_u.dirty_list[i].mptr;
- if (dp->p.mp_pgno != next) {
+ if (dp->mp_pgno != next) {
if (n) {
- DPRINTF("committing %u dirty pages", n);
rc = writev(env->me_fd, iov, n);
if (rc != size) {
- n = errno;
+ n = ErrCode();
if (rc > 0)
- DPRINTF("short write, filesystem full?");
+ DPUTS("short write, filesystem full?");
else
- DPRINTF("writev: %s", strerror(errno));
+ DPRINTF("writev: %s", strerror(n));
mdb_txn_abort(txn);
return n;
}
n = 0;
size = 0;
}
- lseek(env->me_fd, dp->p.mp_pgno * env->me_psize, SEEK_SET);
- next = dp->p.mp_pgno;
+ lseek(env->me_fd, dp->mp_pgno * env->me_psize, SEEK_SET);
+ next = dp->mp_pgno;
}
- DPRINTF("committing page %lu", dp->p.mp_pgno);
- iov[n].iov_len = env->me_psize * dp->h.md_num;
- iov[n].iov_base = &dp->p;
+ DPRINTF("committing page %zu", dp->mp_pgno);
+ iov[n].iov_len = env->me_psize;
+ if (IS_OVERFLOW(dp)) iov[n].iov_len *= dp->mp_pages;
+ iov[n].iov_base = (char *)dp;
size += iov[n].iov_len;
- next = dp->p.mp_pgno + dp->h.md_num;
+ next = dp->mp_pgno + (IS_OVERFLOW(dp) ? dp->mp_pages : 1);
/* clear dirty flag */
- dp->p.mp_flags &= ~P_DIRTY;
+ dp->mp_flags &= ~P_DIRTY;
if (++n >= MDB_COMMIT_PAGES) {
done = 0;
+ i++;
break;
}
}
if (n == 0)
break;
- DPRINTF("committing %u dirty pages", n);
rc = writev(env->me_fd, iov, n);
if (rc != size) {
- n = errno;
+ n = ErrCode();
if (rc > 0)
- DPRINTF("short write, filesystem full?");
+ DPUTS("short write, filesystem full?");
else
- DPRINTF("writev: %s", strerror(errno));
+ DPRINTF("writev: %s", strerror(n));
mdb_txn_abort(txn);
return n;
}
-
+#endif
} while (!done);
/* Drop the dirty pages.
*/
- for (i=1; i<=txn->mt_u.dirty_list[0].mid; i++)
- free(txn->mt_u.dirty_list[i].mptr);
+ for (i=1; i<=txn->mt_u.dirty_list[0].mid; i++) {
+ dp = txn->mt_u.dirty_list[i].mptr;
+ if (!IS_OVERFLOW(dp) || dp->mp_pages == 1) {
+ dp->mp_next = txn->mt_env->me_dpages;
+ VGMEMP_FREE(txn->mt_env, dp);
+ txn->mt_env->me_dpages = dp;
+ } else {
+ VGMEMP_FREE(txn->mt_env, dp);
+ free(dp);
+ }
+ txn->mt_u.dirty_list[i].mid = 0;
+ }
+ txn->mt_u.dirty_list[0].mid = 0;
if ((n = mdb_env_sync(env, 0)) != 0 ||
(n = mdb_env_write_meta(txn)) != MDB_SUCCESS) {
mdb_txn_abort(txn);
return n;
}
- env->me_txn = NULL;
+ env->me_wtxnid = txn->mt_txnid;
+done:
+ env->me_txn = NULL;
/* update the DB tables */
{
int toggle = !env->me_db_toggle;
+ MDB_db *ip, *jp;
+ MDB_dbi i;
- for (i = 2; i < env->me_numdbs; i++) {
- if (txn->mt_dbxs[i].md_dirty) {
- env->me_dbs[toggle][i] = txn->mt_dbs[i];
- txn->mt_dbxs[i].md_dirty = 0;
- }
- }
- for (i = env->me_numdbs; i < txn->mt_numdbs; i++) {
- txn->mt_dbxs[i].md_dirty = 0;
- env->me_dbxs[i] = txn->mt_dbxs[i];
- env->me_dbs[toggle][i] = txn->mt_dbs[i];
+ ip = &env->me_dbs[toggle][2];
+ jp = &txn->mt_dbs[2];
+ LAZY_RWLOCK_WRLOCK(&env->me_dblock);
+ for (i = 2; i < txn->mt_numdbs; i++) {
+ if (ip->md_root != jp->md_root)
+ *ip = *jp;
+ ip++; jp++;
}
+
env->me_db_toggle = toggle;
env->me_numdbs = txn->mt_numdbs;
-
- free(txn->mt_dbs);
+ LAZY_RWLOCK_UNLOCK(&env->me_dblock);
}
- pthread_mutex_unlock(&env->me_txns->mti_wmutex);
+ UNLOCK_MUTEX_W(env);
free(txn);
- txn = NULL;
-
-done:
- mdb_txn_abort(txn);
return MDB_SUCCESS;
}
+/** Read the environment parameters of a DB environment before
+ * mapping it into memory.
+ * @param[in] env the environment handle
+ * @param[out] meta address of where to store the meta information
+ * @return 0 on success, non-zero on failure.
+ */
static int
mdb_env_read_header(MDB_env *env, MDB_meta *meta)
{
- char page[PAGESIZE];
+ MDB_pagebuf pbuf;
MDB_page *p;
MDB_meta *m;
- int rc;
-
- assert(env != NULL);
+ int rc, err;
/* We don't know the page size yet, so use a minimum value.
*/
- if ((rc = pread(env->me_fd, page, PAGESIZE, 0)) == 0) {
+#ifdef _WIN32
+ if (!ReadFile(env->me_fd, &pbuf, MDB_PAGESIZE, (DWORD *)&rc, NULL) || rc == 0)
+#else
+ if ((rc = read(env->me_fd, &pbuf, MDB_PAGESIZE)) == 0)
+#endif
+ {
return ENOENT;
- } else if (rc != PAGESIZE) {
+ }
+ else if (rc != MDB_PAGESIZE) {
+ err = ErrCode();
if (rc > 0)
- errno = EINVAL;
- DPRINTF("read: %s", strerror(errno));
- return errno;
+ err = EINVAL;
+ DPRINTF("read: %s", strerror(err));
+ return err;
}
- p = (MDB_page *)page;
+ p = (MDB_page *)&pbuf;
if (!F_ISSET(p->mp_flags, P_META)) {
- DPRINTF("page %lu not a meta page", p->mp_pgno);
+ DPRINTF("page %zu not a meta page", p->mp_pgno);
return EINVAL;
}
m = METADATA(p);
if (m->mm_magic != MDB_MAGIC) {
- DPRINTF("meta has invalid magic");
+ DPUTS("meta has invalid magic");
return EINVAL;
}
return 0;
}
+/** Write the environment parameters of a freshly created DB environment.
+ * @param[in] env the environment handle
+ * @param[out] meta address of where to store the meta information
+ * @return 0 on success, non-zero on failure.
+ */
static int
mdb_env_init_meta(MDB_env *env, MDB_meta *meta)
{
int rc;
unsigned int psize;
- DPRINTF("writing new meta page");
- psize = sysconf(_SC_PAGE_SIZE);
+ DPUTS("writing new meta page");
+
+ GET_PAGESIZE(psize);
meta->mm_magic = MDB_MAGIC;
meta->mm_version = MDB_VERSION;
m = METADATA(q);
memcpy(m, meta, sizeof(*meta));
+#ifdef _WIN32
+ {
+ DWORD len;
+ rc = WriteFile(env->me_fd, p, psize * 2, &len, NULL);
+ rc = (len == psize * 2) ? MDB_SUCCESS : ErrCode();
+ }
+#else
rc = write(env->me_fd, p, psize * 2);
+ rc = (rc == (int)psize * 2) ? MDB_SUCCESS : ErrCode();
+#endif
free(p);
- return (rc == (int)psize * 2) ? MDB_SUCCESS : errno;
+ return rc;
}
+/** Update the environment info to commit a transaction.
+ * @param[in] txn the transaction that's being committed
+ * @return 0 on success, non-zero on failure.
+ */
static int
mdb_env_write_meta(MDB_txn *txn)
{
off_t off;
int rc, len, toggle;
char *ptr;
+#ifdef _WIN32
+ OVERLAPPED ov;
+#endif
assert(txn != NULL);
assert(txn->mt_env != NULL);
- toggle = !F_ISSET(txn->mt_flags, MDB_TXN_METOGGLE);
- DPRINTF("writing meta page %d for root page %lu",
+ toggle = !txn->mt_toggle;
+ DPRINTF("writing meta page %d for root page %zu",
toggle, txn->mt_dbs[MAIN_DBI].md_root);
env = txn->mt_env;
off += PAGEHDRSZ;
/* Write to the SYNC fd */
+#ifdef _WIN32
+ {
+ memset(&ov, 0, sizeof(ov));
+ ov.Offset = off;
+ WriteFile(env->me_mfd, ptr, len, (DWORD *)&rc, &ov);
+ }
+#else
rc = pwrite(env->me_mfd, ptr, len, off);
+#endif
if (rc != len) {
- DPRINTF("write failed, disk error?");
+ int r2;
+ rc = ErrCode();
+ DPUTS("write failed, disk error?");
/* On a failure, the pagecache still contains the new data.
* Write some old data back, to prevent it from being used.
* Use the non-SYNC fd; we know it will fail anyway.
*/
meta.mm_last_pg = metab.mm_last_pg;
meta.mm_txnid = metab.mm_txnid;
- rc = pwrite(env->me_fd, ptr, len, off);
+#ifdef _WIN32
+ WriteFile(env->me_fd, ptr, len, NULL, &ov);
+#else
+ r2 = pwrite(env->me_fd, ptr, len, off);
+#endif
env->me_flags |= MDB_FATAL_ERROR;
- return errno;
+ return rc;
}
+ /* Memory ordering issues are irrelevant; since the entire writer
+ * is wrapped by wmutex, all of these changes will become visible
+ * after the wmutex is unlocked. Since the DB is multi-version,
+ * readers will get consistent data regardless of how fresh or
+ * how stale their view of these values is.
+ */
+ LAZY_MUTEX_LOCK(&env->me_txns->mti_mutex);
txn->mt_env->me_txns->mti_me_toggle = toggle;
+ txn->mt_env->me_txns->mti_txnid = txn->mt_txnid;
+ LAZY_MUTEX_UNLOCK(&env->me_txns->mti_mutex);
return MDB_SUCCESS;
}
+/** Check both meta pages to see which one is newer.
+ * @param[in] env the environment handle
+ * @param[out] which address of where to store the meta toggle ID
+ * @return 0 on success, non-zero on failure.
+ */
static int
mdb_env_read_meta(MDB_env *env, int *which)
{
assert(env != NULL);
- if (which)
- toggle = *which;
- else if (env->me_metas[0]->mm_txnid < env->me_metas[1]->mm_txnid)
+ if (env->me_metas[0]->mm_txnid < env->me_metas[1]->mm_txnid)
toggle = 1;
- if (env->me_meta != env->me_metas[toggle])
- env->me_meta = env->me_metas[toggle];
-
DPRINTF("Using meta page %d", toggle);
+ *which = toggle;
return MDB_SUCCESS;
}
MDB_env *e;
e = calloc(1, sizeof(MDB_env));
- if (!e) return ENOMEM;
+ if (!e)
+ return ENOMEM;
+ e->me_free_pgs = mdb_midl_alloc();
+ if (!e->me_free_pgs) {
+ free(e);
+ return ENOMEM;
+ }
e->me_maxreaders = DEFAULT_READERS;
e->me_maxdbs = 2;
- e->me_fd = -1;
- e->me_lfd = -1;
- e->me_mfd = -1;
+ e->me_fd = INVALID_HANDLE_VALUE;
+ e->me_lfd = INVALID_HANDLE_VALUE;
+ e->me_mfd = INVALID_HANDLE_VALUE;
+ VGMEMP_CREATE(e,0,0);
*env = e;
return MDB_SUCCESS;
}
if (env->me_map)
return EINVAL;
env->me_mapsize = size;
+ if (env->me_psize)
+ env->me_maxpg = env->me_mapsize / env->me_psize;
return MDB_SUCCESS;
}
int
-mdb_env_set_maxdbs(MDB_env *env, int dbs)
+mdb_env_set_maxdbs(MDB_env *env, MDB_dbi dbs)
{
+ if (env->me_map)
+ return EINVAL;
env->me_maxdbs = dbs;
return MDB_SUCCESS;
}
int
-mdb_env_set_maxreaders(MDB_env *env, int readers)
+mdb_env_set_maxreaders(MDB_env *env, unsigned int readers)
{
+ if (env->me_map || readers < 1)
+ return EINVAL;
env->me_maxreaders = readers;
return MDB_SUCCESS;
}
int
-mdb_env_get_maxreaders(MDB_env *env, int *readers)
+mdb_env_get_maxreaders(MDB_env *env, unsigned int *readers)
{
if (!env || !readers)
return EINVAL;
return MDB_SUCCESS;
}
+/** Further setup required for opening an MDB environment
+ */
static int
mdb_env_open2(MDB_env *env, unsigned int flags)
{
- int i, newenv = 0;
+ int i, newenv = 0, toggle;
MDB_meta meta;
MDB_page *p;
if ((i = mdb_env_read_header(env, &meta)) != 0) {
if (i != ENOENT)
return i;
- DPRINTF("new mdbenv");
+ DPUTS("new mdbenv");
newenv = 1;
}
env->me_mapsize = newenv ? DEFAULT_MAPSIZE : meta.mm_mapsize;
}
+#ifdef _WIN32
+ {
+ HANDLE mh;
+ LONG sizelo, sizehi;
+ sizelo = env->me_mapsize & 0xffffffff;
+ sizehi = env->me_mapsize >> 16; /* pointless on WIN32, only needed on W64 */
+ sizehi >>= 16;
+ /* Windows won't create mappings for zero length files.
+ * Just allocate the maxsize right now.
+ */
+ if (newenv) {
+ SetFilePointer(env->me_fd, sizelo, sizehi ? &sizehi : NULL, 0);
+ if (!SetEndOfFile(env->me_fd))
+ return ErrCode();
+ SetFilePointer(env->me_fd, 0, NULL, 0);
+ }
+ mh = CreateFileMapping(env->me_fd, NULL, PAGE_READONLY,
+ sizehi, sizelo, NULL);
+ if (!mh)
+ return ErrCode();
+ env->me_map = MapViewOfFileEx(mh, FILE_MAP_READ, 0, 0, env->me_mapsize,
+ meta.mm_address);
+ CloseHandle(mh);
+ if (!env->me_map)
+ return ErrCode();
+ }
+#else
i = MAP_SHARED;
if (meta.mm_address && (flags & MDB_FIXEDMAP))
i |= MAP_FIXED;
env->me_map = mmap(meta.mm_address, env->me_mapsize, PROT_READ, i,
env->me_fd, 0);
- if (env->me_map == MAP_FAILED)
- return errno;
+ if (env->me_map == MAP_FAILED) {
+ env->me_map = NULL;
+ return ErrCode();
+ }
+#endif
if (newenv) {
meta.mm_mapsize = env->me_mapsize;
env->me_metas[0] = METADATA(p);
env->me_metas[1] = (MDB_meta *)((char *)env->me_metas[0] + meta.mm_psize);
- if ((i = mdb_env_read_meta(env, NULL)) != 0)
+ if ((i = mdb_env_read_meta(env, &toggle)) != 0)
return i;
DPRINTF("opened database version %u, pagesize %u",
- env->me_meta->mm_version, env->me_psize);
- DPRINTF("depth: %u", env->me_meta->mm_dbs[MAIN_DBI].md_depth);
- DPRINTF("entries: %lu", env->me_meta->mm_dbs[MAIN_DBI].md_entries);
- DPRINTF("branch pages: %lu", env->me_meta->mm_dbs[MAIN_DBI].md_branch_pages);
- DPRINTF("leaf pages: %lu", env->me_meta->mm_dbs[MAIN_DBI].md_leaf_pages);
- DPRINTF("overflow pages: %lu", env->me_meta->mm_dbs[MAIN_DBI].md_overflow_pages);
- DPRINTF("root: %lu", env->me_meta->mm_dbs[MAIN_DBI].md_root);
+ env->me_metas[toggle]->mm_version, env->me_psize);
+ DPRINTF("depth: %u", env->me_metas[toggle]->mm_dbs[MAIN_DBI].md_depth);
+ DPRINTF("entries: %zu", env->me_metas[toggle]->mm_dbs[MAIN_DBI].md_entries);
+ DPRINTF("branch pages: %zu", env->me_metas[toggle]->mm_dbs[MAIN_DBI].md_branch_pages);
+ DPRINTF("leaf pages: %zu", env->me_metas[toggle]->mm_dbs[MAIN_DBI].md_leaf_pages);
+ DPRINTF("overflow pages: %zu", env->me_metas[toggle]->mm_dbs[MAIN_DBI].md_overflow_pages);
+ DPRINTF("root: %zu", env->me_metas[toggle]->mm_dbs[MAIN_DBI].md_root);
return MDB_SUCCESS;
}
+#ifndef _WIN32
+/** Release a reader thread's slot in the reader lock table.
+ * This function is called automatically when a thread exits.
+ * Windows doesn't support destructor callbacks for thread-specific storage,
+ * so this function is not compiled there.
+ * @param[in] ptr This points to the slot in the reader lock table.
+ */
static void
mdb_env_reader_dest(void *ptr)
{
reader->mr_pid = 0;
reader->mr_tid = 0;
}
+#endif
-/* downgrade the exclusive lock on the region back to shared */
+/** Downgrade the exclusive lock on the region back to shared */
static void
mdb_env_share_locks(MDB_env *env)
{
- struct flock lock_info;
+ int toggle = 0;
- env->me_txns->mti_txnid = env->me_meta->mm_txnid;
if (env->me_metas[0]->mm_txnid < env->me_metas[1]->mm_txnid)
- env->me_txns->mti_me_toggle = 1;
+ toggle = 1;
+ env->me_txns->mti_me_toggle = toggle;
+ env->me_txns->mti_txnid = env->me_metas[toggle]->mm_txnid;
+
+#ifdef _WIN32
+ {
+ OVERLAPPED ov;
+ /* First acquire a shared lock. The Unlock will
+ * then release the existing exclusive lock.
+ */
+ memset(&ov, 0, sizeof(ov));
+ LockFileEx(env->me_lfd, 0, 0, 1, 0, &ov);
+ UnlockFile(env->me_lfd, 0, 0, 1, 0);
+ }
+#else
+ {
+ struct flock lock_info;
+ /* The shared lock replaces the existing lock */
+ memset((void *)&lock_info, 0, sizeof(lock_info));
+ lock_info.l_type = F_RDLCK;
+ lock_info.l_whence = SEEK_SET;
+ lock_info.l_start = 0;
+ lock_info.l_len = 1;
+ fcntl(env->me_lfd, F_SETLK, &lock_info);
+ }
+#endif
+}
+#if defined(_WIN32) || defined(__APPLE__)
+/*
+ * hash_64 - 64 bit Fowler/Noll/Vo-0 FNV-1a hash code
+ *
+ * @(#) $Revision: 5.1 $
+ * @(#) $Id: hash_64a.c,v 5.1 2009/06/30 09:01:38 chongo Exp $
+ * @(#) $Source: /usr/local/src/cmd/fnv/RCS/hash_64a.c,v $
+ *
+ * http://www.isthe.com/chongo/tech/comp/fnv/index.html
+ *
+ ***
+ *
+ * Please do not copyright this code. This code is in the public domain.
+ *
+ * LANDON CURT NOLL DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+ * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO
+ * EVENT SHALL LANDON CURT NOLL BE LIABLE FOR ANY SPECIAL, INDIRECT OR
+ * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF
+ * USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
+ * OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+ * PERFORMANCE OF THIS SOFTWARE.
+ *
+ * By:
+ * chongo <Landon Curt Noll> /\oo/\
+ * http://www.isthe.com/chongo/
+ *
+ * Share and Enjoy! :-)
+ */
- memset((void *)&lock_info, 0, sizeof(lock_info));
- lock_info.l_type = F_RDLCK;
- lock_info.l_whence = SEEK_SET;
- lock_info.l_start = 0;
- lock_info.l_len = 1;
- fcntl(env->me_lfd, F_SETLK, &lock_info);
+typedef unsigned long long mdb_hash_t;
+#define MDB_HASH_INIT ((mdb_hash_t)0xcbf29ce484222325ULL)
+
+/** perform a 64 bit Fowler/Noll/Vo FNV-1a hash on a buffer
+ * @param[in] str string to hash
+ * @param[in] hval initial value for hash
+ * @return 64 bit hash
+ *
+ * NOTE: To use the recommended 64 bit FNV-1a hash, use MDB_HASH_INIT as the
+ * hval arg on the first call.
+ */
+static mdb_hash_t
+mdb_hash_str(char *str, mdb_hash_t hval)
+{
+ unsigned char *s = (unsigned char *)str; /* unsigned string */
+ /*
+ * FNV-1a hash each octet of the string
+ */
+ while (*s) {
+ /* xor the bottom with the current octet */
+ hval ^= (mdb_hash_t)*s++;
+
+ /* multiply by the 64 bit FNV magic prime mod 2^64 */
+ hval += (hval << 1) + (hval << 4) + (hval << 5) +
+ (hval << 7) + (hval << 8) + (hval << 40);
+ }
+ /* return our new hash value */
+ return hval;
+}
+
+/** Hash the string and output the hash in hex.
+ * @param[in] str string to hash
+ * @param[out] hexbuf an array of 17 chars to hold the hash
+ */
+static void
+mdb_hash_hex(char *str, char *hexbuf)
+{
+ int i;
+ mdb_hash_t h = mdb_hash_str(str, MDB_HASH_INIT);
+ for (i=0; i<8; i++) {
+ hexbuf += sprintf(hexbuf, "%02x", (unsigned int)h & 0xff);
+ h >>= 8;
+ }
}
+#endif
+/** Open and/or initialize the lock region for the environment.
+ * @param[in] env The MDB environment.
+ * @param[in] lpath The pathname of the file used for the lock region.
+ * @param[in] mode The Unix permissions for the file, if we create it.
+ * @param[out] excl Set to true if we got an exclusive lock on the region.
+ * @return 0 on success, non-zero on failure.
+ */
static int
mdb_env_setup_locks(MDB_env *env, char *lpath, int mode, int *excl)
{
int rc;
off_t size, rsize;
- struct flock lock_info;
*excl = 0;
+#ifdef _WIN32
+ if ((env->me_lfd = CreateFile(lpath, GENERIC_READ|GENERIC_WRITE,
+ FILE_SHARE_READ|FILE_SHARE_WRITE, NULL, OPEN_ALWAYS,
+ FILE_ATTRIBUTE_NORMAL, NULL)) == INVALID_HANDLE_VALUE) {
+ rc = ErrCode();
+ return rc;
+ }
+ /* Try to get exclusive lock. If we succeed, then
+ * nobody is using the lock region and we should initialize it.
+ */
+ {
+ if (LockFile(env->me_lfd, 0, 0, 1, 0)) {
+ *excl = 1;
+ } else {
+ OVERLAPPED ov;
+ memset(&ov, 0, sizeof(ov));
+ if (!LockFileEx(env->me_lfd, 0, 0, 1, 0, &ov)) {
+ rc = ErrCode();
+ goto fail;
+ }
+ }
+ }
+ size = GetFileSize(env->me_lfd, NULL);
+#else
if ((env->me_lfd = open(lpath, O_RDWR|O_CREAT, mode)) == -1) {
- rc = errno;
+ rc = ErrCode();
return rc;
}
/* Try to get exclusive lock. If we succeed, then
* nobody is using the lock region and we should initialize it.
*/
- memset((void *)&lock_info, 0, sizeof(lock_info));
- lock_info.l_type = F_WRLCK;
- lock_info.l_whence = SEEK_SET;
- lock_info.l_start = 0;
- lock_info.l_len = 1;
- rc = fcntl(env->me_lfd, F_SETLK, &lock_info);
- if (rc == 0) {
- *excl = 1;
- } else {
- lock_info.l_type = F_RDLCK;
- rc = fcntl(env->me_lfd, F_SETLK, &lock_info);
- if (rc) {
- rc = errno;
- goto fail;
+ {
+ struct flock lock_info;
+ memset((void *)&lock_info, 0, sizeof(lock_info));
+ lock_info.l_type = F_WRLCK;
+ lock_info.l_whence = SEEK_SET;
+ lock_info.l_start = 0;
+ lock_info.l_len = 1;
+ rc = fcntl(env->me_lfd, F_SETLK, &lock_info);
+ if (rc == 0) {
+ *excl = 1;
+ } else {
+ lock_info.l_type = F_RDLCK;
+ rc = fcntl(env->me_lfd, F_SETLKW, &lock_info);
+ if (rc) {
+ rc = ErrCode();
+ goto fail;
+ }
}
}
size = lseek(env->me_lfd, 0, SEEK_END);
+#endif
rsize = (env->me_maxreaders-1) * sizeof(MDB_reader) + sizeof(MDB_txninfo);
if (size < rsize && *excl) {
+#ifdef _WIN32
+ SetFilePointer(env->me_lfd, rsize, NULL, 0);
+ if (!SetEndOfFile(env->me_lfd)) {
+ rc = ErrCode();
+ goto fail;
+ }
+#else
if (ftruncate(env->me_lfd, rsize) != 0) {
- rc = errno;
+ rc = ErrCode();
goto fail;
}
+#endif
} else {
rsize = size;
size = rsize - sizeof(MDB_txninfo);
env->me_maxreaders = size/sizeof(MDB_reader) + 1;
}
- env->me_txns = mmap(0, rsize, PROT_READ|PROT_WRITE, MAP_SHARED,
- env->me_lfd, 0);
- if (env->me_txns == MAP_FAILED) {
- rc = errno;
- goto fail;
+ {
+#ifdef _WIN32
+ HANDLE mh;
+ mh = CreateFileMapping(env->me_lfd, NULL, PAGE_READWRITE,
+ 0, 0, NULL);
+ if (!mh) {
+ rc = ErrCode();
+ goto fail;
+ }
+ env->me_txns = MapViewOfFileEx(mh, FILE_MAP_WRITE, 0, 0, rsize, NULL);
+ CloseHandle(mh);
+ if (!env->me_txns) {
+ rc = ErrCode();
+ goto fail;
+ }
+#else
+ void *m = mmap(NULL, rsize, PROT_READ|PROT_WRITE, MAP_SHARED,
+ env->me_lfd, 0);
+ if (m == MAP_FAILED) {
+ env->me_txns = NULL;
+ rc = ErrCode();
+ goto fail;
+ }
+ env->me_txns = m;
+#endif
}
if (*excl) {
+#ifdef _WIN32
+ char hexbuf[17];
+ if (!mdb_sec_inited) {
+ InitializeSecurityDescriptor(&mdb_null_sd,
+ SECURITY_DESCRIPTOR_REVISION);
+ SetSecurityDescriptorDacl(&mdb_null_sd, TRUE, 0, FALSE);
+ mdb_all_sa.nLength = sizeof(SECURITY_ATTRIBUTES);
+ mdb_all_sa.bInheritHandle = FALSE;
+ mdb_all_sa.lpSecurityDescriptor = &mdb_null_sd;
+ mdb_sec_inited = 1;
+ }
+ mdb_hash_hex(lpath, hexbuf);
+ sprintf(env->me_txns->mti_rmname, "Global\\MDBr%s", hexbuf);
+ env->me_rmutex = CreateMutex(&mdb_all_sa, FALSE, env->me_txns->mti_rmname);
+ if (!env->me_rmutex) {
+ rc = ErrCode();
+ goto fail;
+ }
+ sprintf(env->me_txns->mti_wmname, "Global\\MDBw%s", hexbuf);
+ env->me_wmutex = CreateMutex(&mdb_all_sa, FALSE, env->me_txns->mti_wmname);
+ if (!env->me_wmutex) {
+ rc = ErrCode();
+ goto fail;
+ }
+#else /* _WIN32 */
+#ifdef __APPLE__
+ char hexbuf[17];
+ mdb_hash_hex(lpath, hexbuf);
+ sprintf(env->me_txns->mti_rmname, "MDBr%s", hexbuf);
+ if (sem_unlink(env->me_txns->mti_rmname)) {
+ rc = ErrCode();
+ if (rc != ENOENT && rc != EINVAL)
+ goto fail;
+ }
+ env->me_rmutex = sem_open(env->me_txns->mti_rmname, O_CREAT, mode, 1);
+ if (!env->me_rmutex) {
+ rc = ErrCode();
+ goto fail;
+ }
+ sprintf(env->me_txns->mti_wmname, "MDBw%s", hexbuf);
+ if (sem_unlink(env->me_txns->mti_wmname)) {
+ rc = ErrCode();
+ if (rc != ENOENT && rc != EINVAL)
+ goto fail;
+ }
+ env->me_wmutex = sem_open(env->me_txns->mti_wmname, O_CREAT, mode, 1);
+ if (!env->me_wmutex) {
+ rc = ErrCode();
+ goto fail;
+ }
+#else /* __APPLE__ */
pthread_mutexattr_t mattr;
pthread_mutexattr_init(&mattr);
}
pthread_mutex_init(&env->me_txns->mti_mutex, &mattr);
pthread_mutex_init(&env->me_txns->mti_wmutex, &mattr);
+#endif /* __APPLE__ */
+#endif /* _WIN32 */
env->me_txns->mti_version = MDB_VERSION;
env->me_txns->mti_magic = MDB_MAGIC;
env->me_txns->mti_txnid = 0;
} else {
if (env->me_txns->mti_magic != MDB_MAGIC) {
- DPRINTF("lock region has invalid magic");
+ DPUTS("lock region has invalid magic");
rc = EINVAL;
goto fail;
}
rc = MDB_VERSION_MISMATCH;
goto fail;
}
- if (errno != EACCES && errno != EAGAIN) {
- rc = errno;
+ rc = ErrCode();
+ if (rc != EACCES && rc != EAGAIN) {
+ goto fail;
+ }
+#ifdef _WIN32
+ env->me_rmutex = OpenMutex(SYNCHRONIZE, FALSE, env->me_txns->mti_rmname);
+ if (!env->me_rmutex) {
+ rc = ErrCode();
+ goto fail;
+ }
+ env->me_wmutex = OpenMutex(SYNCHRONIZE, FALSE, env->me_txns->mti_wmname);
+ if (!env->me_wmutex) {
+ rc = ErrCode();
goto fail;
}
+#endif
+#ifdef __APPLE__
+ env->me_rmutex = sem_open(env->me_txns->mti_rmname, 0);
+ if (!env->me_rmutex) {
+ rc = ErrCode();
+ goto fail;
+ }
+ env->me_wmutex = sem_open(env->me_txns->mti_wmname, 0);
+ if (!env->me_wmutex) {
+ rc = ErrCode();
+ goto fail;
+ }
+#endif
}
return MDB_SUCCESS;
fail:
close(env->me_lfd);
- env->me_lfd = -1;
+ env->me_lfd = INVALID_HANDLE_VALUE;
return rc;
}
+ /** The name of the lock file in the DB environment */
#define LOCKNAME "/lock.mdb"
+ /** The name of the data file in the DB environment */
#define DATANAME "/data.mdb"
+ /** The suffix of the lock file when no subdir is used */
+#define LOCKSUFF "-lock"
+
int
mdb_env_open(MDB_env *env, const char *path, unsigned int flags, mode_t mode)
{
char *lpath, *dpath;
len = strlen(path);
- lpath = malloc(len + sizeof(LOCKNAME) + len + sizeof(DATANAME));
+ if (flags & MDB_NOSUBDIR) {
+ rc = len + sizeof(LOCKSUFF) + len + 1;
+ } else {
+ rc = len + sizeof(LOCKNAME) + len + sizeof(DATANAME);
+ }
+ lpath = malloc(rc);
if (!lpath)
return ENOMEM;
- dpath = lpath + len + sizeof(LOCKNAME);
- sprintf(lpath, "%s" LOCKNAME, path);
- sprintf(dpath, "%s" DATANAME, path);
+ if (flags & MDB_NOSUBDIR) {
+ dpath = lpath + len + sizeof(LOCKSUFF);
+ sprintf(lpath, "%s" LOCKSUFF, path);
+ strcpy(dpath, path);
+ } else {
+ dpath = lpath + len + sizeof(LOCKNAME);
+ sprintf(lpath, "%s" LOCKNAME, path);
+ sprintf(dpath, "%s" DATANAME, path);
+ }
rc = mdb_env_setup_locks(env, lpath, mode, &excl);
if (rc)
goto leave;
+#ifdef _WIN32
+ if (F_ISSET(flags, MDB_RDONLY)) {
+ oflags = GENERIC_READ;
+ len = OPEN_EXISTING;
+ } else {
+ oflags = GENERIC_READ|GENERIC_WRITE;
+ len = OPEN_ALWAYS;
+ }
+ mode = FILE_ATTRIBUTE_NORMAL;
+ if ((env->me_fd = CreateFile(dpath, oflags, FILE_SHARE_READ|FILE_SHARE_WRITE,
+ NULL, len, mode, NULL)) == INVALID_HANDLE_VALUE) {
+ rc = ErrCode();
+ goto leave;
+ }
+#else
if (F_ISSET(flags, MDB_RDONLY))
oflags = O_RDONLY;
else
oflags = O_RDWR | O_CREAT;
if ((env->me_fd = open(dpath, oflags, mode)) == -1) {
- rc = errno;
+ rc = ErrCode();
goto leave;
}
+#endif
if ((rc = mdb_env_open2(env, flags)) == MDB_SUCCESS) {
/* synchronous fd for meta writes */
+#ifdef _WIN32
+ if (!(flags & (MDB_RDONLY|MDB_NOSYNC)))
+ mode |= FILE_FLAG_WRITE_THROUGH;
+ if ((env->me_mfd = CreateFile(dpath, oflags, FILE_SHARE_READ|FILE_SHARE_WRITE,
+ NULL, len, mode, NULL)) == INVALID_HANDLE_VALUE) {
+ rc = ErrCode();
+ goto leave;
+ }
+#else
if (!(flags & (MDB_RDONLY|MDB_NOSYNC)))
- oflags |= O_DSYNC;
+ oflags |= MDB_DSYNC;
if ((env->me_mfd = open(dpath, oflags, mode)) == -1) {
- rc = errno;
+ rc = ErrCode();
goto leave;
}
-
+#endif
env->me_path = strdup(path);
DPRINTF("opened dbenv %p", (void *) env);
pthread_key_create(&env->me_txkey, mdb_env_reader_dest);
+ LAZY_RWLOCK_INIT(&env->me_dblock, NULL);
if (excl)
mdb_env_share_locks(env);
env->me_dbxs = calloc(env->me_maxdbs, sizeof(MDB_dbx));
leave:
if (rc) {
- if (env->me_fd >= 0) {
+ if (env->me_fd != INVALID_HANDLE_VALUE) {
close(env->me_fd);
- env->me_fd = -1;
+ env->me_fd = INVALID_HANDLE_VALUE;
}
- if (env->me_lfd >= 0) {
+ if (env->me_lfd != INVALID_HANDLE_VALUE) {
close(env->me_lfd);
- env->me_lfd = -1;
+ env->me_lfd = INVALID_HANDLE_VALUE;
}
}
free(lpath);
void
mdb_env_close(MDB_env *env)
{
+ MDB_page *dp;
+
if (env == NULL)
return;
+ VGMEMP_DESTROY(env);
+ while (env->me_dpages) {
+ dp = env->me_dpages;
+ VGMEMP_DEFINED(&dp->mp_next, sizeof(dp->mp_next));
+ env->me_dpages = dp->mp_next;
+ free(dp);
+ }
+
free(env->me_dbs[1]);
free(env->me_dbs[0]);
free(env->me_dbxs);
free(env->me_path);
+ LAZY_RWLOCK_DESTROY(&env->me_dblock);
pthread_key_delete(env->me_txkey);
if (env->me_map) {
close(env->me_fd);
if (env->me_txns) {
pid_t pid = getpid();
- size_t size = (env->me_maxreaders-1) * sizeof(MDB_reader) + sizeof(MDB_txninfo);
- int i;
+ unsigned int i;
for (i=0; i<env->me_txns->mti_numreaders; i++)
if (env->me_txns->mti_readers[i].mr_pid == pid)
env->me_txns->mti_readers[i].mr_pid = 0;
- munmap(env->me_txns, size);
+ munmap((void *)env->me_txns, (env->me_maxreaders-1)*sizeof(MDB_reader)+sizeof(MDB_txninfo));
}
close(env->me_lfd);
+ mdb_midl_free(env->me_free_pgs);
free(env);
}
-/* Search for key within a leaf page, using binary search.
+/** Compare two items pointing at aligned size_t's */
+static int
+mdb_cmp_long(const MDB_val *a, const MDB_val *b)
+{
+ return (*(size_t *)a->mv_data < *(size_t *)b->mv_data) ? -1 :
+ *(size_t *)a->mv_data > *(size_t *)b->mv_data;
+}
+
+/** Compare two items pointing at aligned int's */
+static int
+mdb_cmp_int(const MDB_val *a, const MDB_val *b)
+{
+ return (*(unsigned int *)a->mv_data < *(unsigned int *)b->mv_data) ? -1 :
+ *(unsigned int *)a->mv_data > *(unsigned int *)b->mv_data;
+}
+
+/** Compare two items pointing at ints of unknown alignment.
+ * Nodes and keys are guaranteed to be 2-byte aligned.
+ */
+static int
+mdb_cmp_cint(const MDB_val *a, const MDB_val *b)
+{
+#if BYTE_ORDER == LITTLE_ENDIAN
+ unsigned short *u, *c;
+ int x;
+
+ u = (unsigned short *) ((char *) a->mv_data + a->mv_size);
+ c = (unsigned short *) ((char *) b->mv_data + a->mv_size);
+ do {
+ x = *--u - *--c;
+ } while(!x && u > (unsigned short *)a->mv_data);
+ return x;
+#else
+ return memcmp(a->mv_data, b->mv_data, a->mv_size);
+#endif
+}
+
+/** Compare two items lexically */
+static int
+mdb_cmp_memn(const MDB_val *a, const MDB_val *b)
+{
+ int diff;
+ ssize_t len_diff;
+ unsigned int len;
+
+ len = a->mv_size;
+ len_diff = (ssize_t) a->mv_size - (ssize_t) b->mv_size;
+ if (len_diff > 0) {
+ len = b->mv_size;
+ len_diff = 1;
+ }
+
+ diff = memcmp(a->mv_data, b->mv_data, len);
+ return diff ? diff : len_diff<0 ? -1 : len_diff;
+}
+
+/** Compare two items in reverse byte order */
+static int
+mdb_cmp_memnr(const MDB_val *a, const MDB_val *b)
+{
+ const unsigned char *p1, *p2, *p1_lim;
+ ssize_t len_diff;
+ int diff;
+
+ p1_lim = (const unsigned char *)a->mv_data;
+ p1 = (const unsigned char *)a->mv_data + a->mv_size;
+ p2 = (const unsigned char *)b->mv_data + b->mv_size;
+
+ len_diff = (ssize_t) a->mv_size - (ssize_t) b->mv_size;
+ if (len_diff > 0) {
+ p1_lim += len_diff;
+ len_diff = 1;
+ }
+
+ while (p1 > p1_lim) {
+ diff = *--p1 - *--p2;
+ if (diff)
+ return diff;
+ }
+ return len_diff<0 ? -1 : len_diff;
+}
+
+/** Search for key within a page, using binary search.
* Returns the smallest entry larger or equal to the key.
* If exactp is non-null, stores whether the found entry was an exact match
* in *exactp (1 or 0).
- * If kip is non-null, stores the index of the found entry in *kip.
+ * Updates the cursor index with the index of the found entry.
* If no entry larger or equal to the key is found, returns NULL.
*/
static MDB_node *
-mdb_search_node(MDB_txn *txn, MDB_dbi dbi, MDB_page *mp, MDB_val *key,
- int *exactp, unsigned int *kip)
+mdb_node_search(MDB_cursor *mc, MDB_val *key, int *exactp)
{
- unsigned int i = 0;
+ unsigned int i = 0, nkeys;
int low, high;
int rc = 0;
- MDB_node *node;
+ MDB_page *mp = mc->mc_pg[mc->mc_top];
+ MDB_node *node = NULL;
MDB_val nodekey;
+ MDB_cmp_func *cmp;
+ DKBUF;
- DPRINTF("searching %u keys in %s page %lu",
- NUMKEYS(mp),
- IS_LEAF(mp) ? "leaf" : "branch",
- mp->mp_pgno);
+ nkeys = NUMKEYS(mp);
- assert(NUMKEYS(mp) > 0);
+#if MDB_DEBUG
+ {
+ pgno_t pgno;
+ COPY_PGNO(pgno, mp->mp_pgno);
+ DPRINTF("searching %u keys in %s %spage %zu",
+ nkeys, IS_LEAF(mp) ? "leaf" : "branch", IS_SUBP(mp) ? "sub-" : "",
+ pgno);
+ }
+#endif
- memset(&nodekey, 0, sizeof(nodekey));
+ assert(nkeys > 0);
low = IS_LEAF(mp) ? 0 : 1;
- high = NUMKEYS(mp) - 1;
- while (low <= high) {
- i = (low + high) >> 1;
- node = NODEPTR(mp, i);
-
- nodekey.mv_size = node->mn_ksize;
- nodekey.mv_data = NODEKEY(node);
+ high = nkeys - 1;
+ cmp = mc->mc_dbx->md_cmp;
- if (txn->mt_dbxs[dbi].md_cmp)
- rc = txn->mt_dbxs[dbi].md_cmp(key, &nodekey);
- else
- rc = _mdb_cmp(txn, dbi, key, &nodekey);
-
- if (IS_LEAF(mp))
- DPRINTF("found leaf index %u [%.*s], rc = %i",
- i, (int)nodekey.mv_size, (char *)nodekey.mv_data, rc);
+ /* Branch pages have no data, so if using integer keys,
+ * alignment is guaranteed. Use faster mdb_cmp_int.
+ */
+ if (cmp == mdb_cmp_cint && IS_BRANCH(mp)) {
+ if (NODEPTR(mp, 1)->mn_ksize == sizeof(size_t))
+ cmp = mdb_cmp_long;
else
- DPRINTF("found branch index %u [%.*s -> %lu], rc = %i",
- i, (int)node->mn_ksize, (char *)NODEKEY(node),
- node->mn_pgno, rc);
+ cmp = mdb_cmp_int;
+ }
- if (rc == 0)
- break;
- if (rc > 0)
- low = i + 1;
- else
- high = i - 1;
+ if (IS_LEAF2(mp)) {
+ nodekey.mv_size = mc->mc_db->md_pad;
+ node = NODEPTR(mp, 0); /* fake */
+ while (low <= high) {
+ i = (low + high) >> 1;
+ nodekey.mv_data = LEAF2KEY(mp, i, nodekey.mv_size);
+ rc = cmp(key, &nodekey);
+ DPRINTF("found leaf index %u [%s], rc = %i",
+ i, DKEY(&nodekey), rc);
+ if (rc == 0)
+ break;
+ if (rc > 0)
+ low = i + 1;
+ else
+ high = i - 1;
+ }
+ } else {
+ while (low <= high) {
+ i = (low + high) >> 1;
+
+ node = NODEPTR(mp, i);
+ nodekey.mv_size = NODEKSZ(node);
+ nodekey.mv_data = NODEKEY(node);
+
+ rc = cmp(key, &nodekey);
+#if MDB_DEBUG
+ if (IS_LEAF(mp))
+ DPRINTF("found leaf index %u [%s], rc = %i",
+ i, DKEY(&nodekey), rc);
+ else
+ DPRINTF("found branch index %u [%s -> %zu], rc = %i",
+ i, DKEY(&nodekey), NODEPGNO(node), rc);
+#endif
+ if (rc == 0)
+ break;
+ if (rc > 0)
+ low = i + 1;
+ else
+ high = i - 1;
+ }
}
if (rc > 0) { /* Found entry is less than the key. */
i++; /* Skip to get the smallest entry larger than key. */
- if (i >= NUMKEYS(mp))
- /* There is no entry larger or equal to the key. */
- return NULL;
+ if (!IS_LEAF2(mp))
+ node = NODEPTR(mp, i);
}
if (exactp)
*exactp = (rc == 0);
- if (kip) /* Store the key index if requested. */
- *kip = i;
+ /* store the key index */
+ mc->mc_ki[mc->mc_top] = i;
+ if (i >= nkeys)
+ /* There is no entry larger or equal to the key. */
+ return NULL;
- return NODEPTR(mp, i);
+ /* nodeptr is fake for LEAF2 */
+ return node;
}
+#if 0
static void
-cursor_pop_page(MDB_cursor *cursor)
+mdb_cursor_adjust(MDB_cursor *mc, func)
{
- MDB_ppage *top;
+ MDB_cursor *m2;
+
+ for (m2 = mc->mc_txn->mt_cursors[mc->mc_dbi]; m2; m2=m2->mc_next) {
+ if (m2->mc_pg[m2->mc_top] == mc->mc_pg[mc->mc_top]) {
+ func(mc, m2);
+ }
+ }
+}
+#endif
- top = CURSOR_TOP(cursor);
- CURSOR_POP(cursor);
+/** Pop a page off the top of the cursor's stack. */
+static void
+mdb_cursor_pop(MDB_cursor *mc)
+{
+ MDB_page *top;
- DPRINTF("popped page %lu off cursor %p", top->mp_page->mp_pgno, (void *) cursor);
+ if (mc->mc_snum) {
+ top = mc->mc_pg[mc->mc_top];
+ mc->mc_snum--;
+ if (mc->mc_snum)
+ mc->mc_top--;
- free(top);
+ DPRINTF("popped page %zu off db %u cursor %p", top->mp_pgno,
+ mc->mc_dbi, (void *) mc);
+ }
}
-static MDB_ppage *
-cursor_push_page(MDB_cursor *cursor, MDB_page *mp)
+/** Push a page onto the top of the cursor's stack. */
+static int
+mdb_cursor_push(MDB_cursor *mc, MDB_page *mp)
{
- MDB_ppage *ppage;
+ DPRINTF("pushing page %zu on db %u cursor %p", mp->mp_pgno,
+ mc->mc_dbi, (void *) mc);
+
+ if (mc->mc_snum >= CURSOR_STACK) {
+ assert(mc->mc_snum < CURSOR_STACK);
+ return ENOMEM;
+ }
- DPRINTF("pushing page %lu on cursor %p", mp->mp_pgno, (void *) cursor);
+ mc->mc_top = mc->mc_snum++;
+ mc->mc_pg[mc->mc_top] = mp;
+ mc->mc_ki[mc->mc_top] = 0;
- if ((ppage = calloc(1, sizeof(MDB_ppage))) == NULL)
- return NULL;
- ppage->mp_page = mp;
- CURSOR_PUSH(cursor, ppage);
- return ppage;
+ return MDB_SUCCESS;
}
-static MDB_page *
-mdb_get_page(MDB_txn *txn, pgno_t pgno)
+/** Find the address of the page corresponding to a given page number.
+ * @param[in] txn the transaction for this access.
+ * @param[in] pgno the page number for the page to retrieve.
+ * @param[out] ret address of a pointer where the page's address will be stored.
+ * @return 0 on success, non-zero on failure.
+ */
+static int
+mdb_page_get(MDB_txn *txn, pgno_t pgno, MDB_page **ret)
{
MDB_page *p = NULL;
- int found = 0;
if (!F_ISSET(txn->mt_flags, MDB_TXN_RDONLY) && txn->mt_u.dirty_list[0].mid) {
- MDB_dpage *dp;
- MIDL2 id;
unsigned x;
- id.mid = pgno;
- x = mdb_midl2_search(txn->mt_u.dirty_list, &id);
+ x = mdb_mid2l_search(txn->mt_u.dirty_list, pgno);
if (x <= txn->mt_u.dirty_list[0].mid && txn->mt_u.dirty_list[x].mid == pgno) {
- dp = txn->mt_u.dirty_list[x].mptr;
- p = &dp->p;
- found = 1;
+ p = txn->mt_u.dirty_list[x].mptr;
}
}
- if (!found) {
- if (pgno > txn->mt_env->me_meta->mm_last_pg)
- return NULL;
- p = (MDB_page *)(txn->mt_env->me_map + txn->mt_env->me_psize * pgno);
+ if (!p) {
+ if (pgno <= txn->mt_env->me_metas[txn->mt_toggle]->mm_last_pg)
+ p = (MDB_page *)(txn->mt_env->me_map + txn->mt_env->me_psize * pgno);
+ }
+ *ret = p;
+ if (!p) {
+ DPRINTF("page %zu not found", pgno);
+ assert(p != NULL);
}
- return p;
+ return (p != NULL) ? MDB_SUCCESS : MDB_PAGE_NOTFOUND;
}
+/** Search for the page a given key should be in.
+ * Pushes parent pages on the cursor stack. This function continues a
+ * search on a cursor that has already been initialized. (Usually by
+ * #mdb_page_search() but also by #mdb_node_move().)
+ * @param[in,out] mc the cursor for this operation.
+ * @param[in] key the key to search for. If NULL, search for the lowest
+ * page. (This is used by #mdb_cursor_first().)
+ * @param[in] modify If true, visited pages are updated with new page numbers.
+ * @return 0 on success, non-zero on failure.
+ */
static int
-mdb_search_page_root(MDB_txn *txn, MDB_dbi dbi, MDB_val *key,
- MDB_cursor *cursor, int modify, MDB_pageparent *mpp)
+mdb_page_search_root(MDB_cursor *mc, MDB_val *key, int modify)
{
- MDB_page *mp = mpp->mp_page;
+ MDB_page *mp = mc->mc_pg[mc->mc_top];
+ DKBUF;
int rc;
- if (cursor && cursor_push_page(cursor, mp) == NULL)
- return ENOMEM;
while (IS_BRANCH(mp)) {
- unsigned int i = 0;
MDB_node *node;
+ indx_t i;
- DPRINTF("branch page %lu has %u keys", mp->mp_pgno, NUMKEYS(mp));
+ DPRINTF("branch page %zu has %u keys", mp->mp_pgno, NUMKEYS(mp));
assert(NUMKEYS(mp) > 1);
- DPRINTF("found index 0 to page %lu", NODEPGNO(NODEPTR(mp, 0)));
+ DPRINTF("found index 0 to page %zu", NODEPGNO(NODEPTR(mp, 0)));
if (key == NULL) /* Initialize cursor to first page. */
i = 0;
i = NUMKEYS(mp)-1;
} else {
int exact;
- node = mdb_search_node(txn, dbi, mp, key, &exact, &i);
+ node = mdb_node_search(mc, key, &exact);
if (node == NULL)
i = NUMKEYS(mp) - 1;
- else if (!exact) {
- assert(i > 0);
- i--;
+ else {
+ i = mc->mc_ki[mc->mc_top];
+ if (!exact) {
+ assert(i > 0);
+ i--;
+ }
}
}
if (key)
- DPRINTF("following index %u for key %.*s",
- i, (int)key->mv_size, (char *)key->mv_data);
+ DPRINTF("following index %u for key [%s]",
+ i, DKEY(key));
assert(i < NUMKEYS(mp));
node = NODEPTR(mp, i);
- if (cursor)
- CURSOR_TOP(cursor)->mp_ki = i;
-
- mpp->mp_parent = mp;
- if ((mp = mdb_get_page(txn, NODEPGNO(node))) == NULL)
- return MDB_PAGE_NOTFOUND;
- mpp->mp_pi = i;
- mpp->mp_page = mp;
+ if ((rc = mdb_page_get(mc->mc_txn, NODEPGNO(node), &mp)))
+ return rc;
- if (cursor && cursor_push_page(cursor, mp) == NULL)
- return ENOMEM;
+ mc->mc_ki[mc->mc_top] = i;
+ if ((rc = mdb_cursor_push(mc, mp)))
+ return rc;
if (modify) {
- MDB_dhead *dh = ((MDB_dhead *)mp)-1;
- if ((rc = mdb_touch(txn, mpp)) != 0)
+ if ((rc = mdb_page_touch(mc)) != 0)
return rc;
- dh = ((MDB_dhead *)mpp->mp_page)-1;
- dh->md_parent = mpp->mp_parent;
- dh->md_pi = mpp->mp_pi;
+ mp = mc->mc_pg[mc->mc_top];
}
-
- mp = mpp->mp_page;
}
if (!IS_LEAF(mp)) {
return MDB_CORRUPTED;
}
- DPRINTF("found leaf page %lu for key %.*s", mp->mp_pgno,
- key ? (int)key->mv_size : 0, key ? (char *)key->mv_data : NULL);
+ DPRINTF("found leaf page %zu for key [%s]", mp->mp_pgno,
+ key ? DKEY(key) : NULL);
return MDB_SUCCESS;
}
-/* Search for the page a given key should be in.
- * Stores a pointer to the found page in *mpp.
- * If key is NULL, search for the lowest page (used by mdb_cursor_first).
- * If cursor is non-null, pushes parent pages on the cursor stack.
- * If modify is true, visited pages are updated with new page numbers.
+/** Search for the page a given key should be in.
+ * Pushes parent pages on the cursor stack. This function just sets up
+ * the search; it finds the root page for \b mc's database and sets this
+ * as the root of the cursor's stack. Then #mdb_page_search_root() is
+ * called to complete the search.
+ * @param[in,out] mc the cursor for this operation.
+ * @param[in] key the key to search for. If NULL, search for the lowest
+ * page. (This is used by #mdb_cursor_first().)
+ * @param[in] modify If true, visited pages are updated with new page numbers.
+ * @return 0 on success, non-zero on failure.
*/
static int
-mdb_search_page(MDB_txn *txn, MDB_dbi dbi, MDB_val *key,
- MDB_cursor *cursor, int modify, MDB_pageparent *mpp)
+mdb_page_search(MDB_cursor *mc, MDB_val *key, int modify)
{
int rc;
pgno_t root;
- /* Choose which root page to start with. If a transaction is given
- * use the root page from the transaction, otherwise read the last
- * committed root page.
+ /* Make sure the txn is still viable, then find the root from
+ * the txn's db table.
*/
- if (F_ISSET(txn->mt_flags, MDB_TXN_ERROR)) {
- DPRINTF("transaction has failed, must abort");
+ if (F_ISSET(mc->mc_txn->mt_flags, MDB_TXN_ERROR)) {
+ DPUTS("transaction has failed, must abort");
return EINVAL;
- } else
- root = txn->mt_dbs[dbi].md_root;
+ } else {
+ /* Make sure we're using an up-to-date root */
+ if (mc->mc_dbi > MAIN_DBI) {
+ if ((*mc->mc_dbflag & DB_STALE) ||
+ (modify && !(*mc->mc_dbflag & DB_DIRTY))) {
+ MDB_cursor mc2;
+ unsigned char dbflag = 0;
+ mdb_cursor_init(&mc2, mc->mc_txn, MAIN_DBI, NULL);
+ rc = mdb_page_search(&mc2, &mc->mc_dbx->md_name, modify);
+ if (rc)
+ return rc;
+ if (*mc->mc_dbflag & DB_STALE) {
+ MDB_val data;
+ int exact = 0;
+ MDB_node *leaf = mdb_node_search(&mc2,
+ &mc->mc_dbx->md_name, &exact);
+ if (!exact)
+ return MDB_NOTFOUND;
+ mdb_node_read(mc->mc_txn, leaf, &data);
+ memcpy(mc->mc_db, data.mv_data, sizeof(MDB_db));
+ }
+ if (modify)
+ dbflag = DB_DIRTY;
+ *mc->mc_dbflag = dbflag;
+ }
+ }
+ root = mc->mc_db->md_root;
- if (root == P_INVALID) { /* Tree is empty. */
- DPRINTF("tree is empty");
- return MDB_NOTFOUND;
+ if (root == P_INVALID) { /* Tree is empty. */
+ DPUTS("tree is empty");
+ return MDB_NOTFOUND;
+ }
}
- if ((mpp->mp_page = mdb_get_page(txn, root)) == NULL)
- return MDB_PAGE_NOTFOUND;
+ assert(root > 1);
+ if ((rc = mdb_page_get(mc->mc_txn, root, &mc->mc_pg[0])))
+ return rc;
+
+ mc->mc_snum = 1;
+ mc->mc_top = 0;
- DPRINTF("root page has flags 0x%X", mpp->mp_page->mp_flags);
+ DPRINTF("db %u root page %zu has flags 0x%X",
+ mc->mc_dbi, root, mc->mc_pg[0]->mp_flags);
if (modify) {
- /* For sub-databases, update main root first */
- if (dbi > MAIN_DBI && !txn->mt_dbxs[dbi].md_dirty) {
- MDB_pageparent mp2;
- rc = mdb_search_page(txn, MAIN_DBI, &txn->mt_dbxs[dbi].md_name,
- NULL, 1, &mp2);
- if (rc)
- return rc;
- txn->mt_dbxs[dbi].md_dirty = 1;
- }
- if (!F_ISSET(mpp->mp_page->mp_flags, P_DIRTY)) {
- mpp->mp_parent = NULL;
- mpp->mp_pi = 0;
- if ((rc = mdb_touch(txn, mpp)))
- return rc;
- txn->mt_dbs[dbi].md_root = mpp->mp_page->mp_pgno;
- }
+ if ((rc = mdb_page_touch(mc)))
+ return rc;
}
- return mdb_search_page_root(txn, dbi, key, cursor, modify, mpp);
+ return mdb_page_search_root(mc, key, modify);
}
+/** Return the data associated with a given node.
+ * @param[in] txn The transaction for this operation.
+ * @param[in] leaf The node being read.
+ * @param[out] data Updated to point to the node's data.
+ * @return 0 on success, non-zero on failure.
+ */
static int
-mdb_read_data(MDB_txn *txn, MDB_node *leaf, MDB_val *data)
+mdb_node_read(MDB_txn *txn, MDB_node *leaf, MDB_val *data)
{
- MDB_page *omp; /* overflow mpage */
+ MDB_page *omp; /* overflow page */
pgno_t pgno;
+ int rc;
if (!F_ISSET(leaf->mn_flags, F_BIGDATA)) {
- data->mv_size = leaf->mn_dsize;
+ data->mv_size = NODEDSZ(leaf);
data->mv_data = NODEDATA(leaf);
return MDB_SUCCESS;
}
/* Read overflow data.
*/
- data->mv_size = leaf->mn_dsize;
+ data->mv_size = NODEDSZ(leaf);
memcpy(&pgno, NODEDATA(leaf), sizeof(pgno));
- if ((omp = mdb_get_page(txn, pgno)) == NULL) {
- DPRINTF("read overflow page %lu failed", pgno);
- return MDB_PAGE_NOTFOUND;
+ if ((rc = mdb_page_get(txn, pgno, &omp))) {
+ DPRINTF("read overflow page %zu failed", pgno);
+ return rc;
}
- data->mv_data = omp;
+ data->mv_data = METADATA(omp);
return MDB_SUCCESS;
}
mdb_get(MDB_txn *txn, MDB_dbi dbi,
MDB_val *key, MDB_val *data)
{
- int rc, exact;
- MDB_node *leaf;
- MDB_pageparent mpp;
+ MDB_cursor mc;
+ MDB_xcursor mx;
+ int exact = 0;
+ DKBUF;
assert(key);
assert(data);
- DPRINTF("===> get key [%.*s]", (int)key->mv_size, (char *)key->mv_data);
+ DPRINTF("===> get db %u key [%s]", dbi, DKEY(key));
if (txn == NULL || !dbi || dbi >= txn->mt_numdbs)
return EINVAL;
return EINVAL;
}
- if ((rc = mdb_search_page(txn, dbi, key, NULL, 0, &mpp)) != MDB_SUCCESS)
- return rc;
-
- leaf = mdb_search_node(txn, dbi, mpp.mp_page, key, &exact, NULL);
- if (leaf && exact) {
- /* Return first duplicate data item */
- if (F_ISSET(txn->mt_dbs[dbi].md_flags, MDB_DUPSORT)) {
- MDB_xcursor mx;
-
- mdb_xcursor_init0(txn, dbi, &mx);
- mdb_xcursor_init1(txn, dbi, &mx, leaf);
- rc = mdb_search_page(&mx.mx_txn, mx.mx_cursor.mc_dbi, NULL, NULL, 0, &mpp);
- if (rc != MDB_SUCCESS)
- return rc;
- leaf = NODEPTR(mpp.mp_page, 0);
- }
- rc = mdb_read_data(txn, leaf, data);
- } else {
- rc = MDB_NOTFOUND;
- }
-
- return rc;
+ mdb_cursor_init(&mc, txn, dbi, &mx);
+ return mdb_cursor_set(&mc, key, data, MDB_SET, &exact);
}
+/** Find a sibling for a page.
+ * Replaces the page at the top of the cursor's stack with the
+ * specified sibling, if one exists.
+ * @param[in] mc The cursor for this operation.
+ * @param[in] move_right Non-zero if the right sibling is requested,
+ * otherwise the left sibling.
+ * @return 0 on success, non-zero on failure.
+ */
static int
-mdb_sibling(MDB_cursor *cursor, int move_right)
+mdb_cursor_sibling(MDB_cursor *mc, int move_right)
{
int rc;
MDB_node *indx;
- MDB_ppage *parent, *top;
MDB_page *mp;
- top = CURSOR_TOP(cursor);
- if ((parent = SLIST_NEXT(top, mp_entry)) == NULL) {
+ if (mc->mc_snum < 2) {
return MDB_NOTFOUND; /* root has no siblings */
}
- DPRINTF("parent page is page %lu, index %u",
- parent->mp_page->mp_pgno, parent->mp_ki);
+ mdb_cursor_pop(mc);
+ DPRINTF("parent page is page %zu, index %u",
+ mc->mc_pg[mc->mc_top]->mp_pgno, mc->mc_ki[mc->mc_top]);
- cursor_pop_page(cursor);
- if (move_right ? (parent->mp_ki + 1 >= NUMKEYS(parent->mp_page))
- : (parent->mp_ki == 0)) {
+ if (move_right ? (mc->mc_ki[mc->mc_top] + 1u >= NUMKEYS(mc->mc_pg[mc->mc_top]))
+ : (mc->mc_ki[mc->mc_top] == 0)) {
DPRINTF("no more keys left, moving to %s sibling",
move_right ? "right" : "left");
- if ((rc = mdb_sibling(cursor, move_right)) != MDB_SUCCESS)
+ if ((rc = mdb_cursor_sibling(mc, move_right)) != MDB_SUCCESS)
return rc;
- parent = CURSOR_TOP(cursor);
} else {
if (move_right)
- parent->mp_ki++;
+ mc->mc_ki[mc->mc_top]++;
else
- parent->mp_ki--;
+ mc->mc_ki[mc->mc_top]--;
DPRINTF("just moving to %s index key %u",
- move_right ? "right" : "left", parent->mp_ki);
+ move_right ? "right" : "left", mc->mc_ki[mc->mc_top]);
}
- assert(IS_BRANCH(parent->mp_page));
+ assert(IS_BRANCH(mc->mc_pg[mc->mc_top]));
- indx = NODEPTR(parent->mp_page, parent->mp_ki);
- if ((mp = mdb_get_page(cursor->mc_txn, indx->mn_pgno)) == NULL)
- return MDB_PAGE_NOTFOUND;
-#if 0
- mp->parent = parent->mp_page;
- mp->parent_index = parent->mp_ki;
-#endif
+ indx = NODEPTR(mc->mc_pg[mc->mc_top], mc->mc_ki[mc->mc_top]);
+ if ((rc = mdb_page_get(mc->mc_txn, NODEPGNO(indx), &mp)))
+ return rc;;
- cursor_push_page(cursor, mp);
+ mdb_cursor_push(mc, mp);
return MDB_SUCCESS;
}
+/** Move the cursor to the next data item. */
static int
-mdb_set_key(MDB_node *node, MDB_val *key)
-{
- if (key == NULL)
- return 0;
-
- key->mv_size = node->mn_ksize;
- key->mv_data = NODEKEY(node);
-
- return 0;
-}
-
-static int
-mdb_cursor_next(MDB_cursor *cursor, MDB_val *key, MDB_val *data, MDB_cursor_op op)
+mdb_cursor_next(MDB_cursor *mc, MDB_val *key, MDB_val *data, MDB_cursor_op op)
{
- MDB_ppage *top;
MDB_page *mp;
MDB_node *leaf;
int rc;
- if (cursor->mc_eof) {
+ if (mc->mc_flags & C_EOF) {
return MDB_NOTFOUND;
}
- assert(cursor->mc_initialized);
+ assert(mc->mc_flags & C_INITIALIZED);
- if (cursor->mc_txn->mt_dbs[cursor->mc_dbi].md_flags & MDB_DUPSORT) {
- if (op == MDB_NEXT || op == MDB_NEXT_DUP) {
- rc = mdb_cursor_next(&cursor->mc_xcursor->mx_cursor, data, NULL, MDB_NEXT);
- if (op != MDB_NEXT || rc == MDB_SUCCESS)
- return rc;
+ mp = mc->mc_pg[mc->mc_top];
+
+ if (mc->mc_db->md_flags & MDB_DUPSORT) {
+ leaf = NODEPTR(mp, mc->mc_ki[mc->mc_top]);
+ if (F_ISSET(leaf->mn_flags, F_DUPDATA)) {
+ if (op == MDB_NEXT || op == MDB_NEXT_DUP) {
+ rc = mdb_cursor_next(&mc->mc_xcursor->mx_cursor, data, NULL, MDB_NEXT);
+ if (op != MDB_NEXT || rc == MDB_SUCCESS)
+ return rc;
+ }
+ } else {
+ mc->mc_xcursor->mx_cursor.mc_flags &= ~C_INITIALIZED;
+ if (op == MDB_NEXT_DUP)
+ return MDB_NOTFOUND;
}
}
- top = CURSOR_TOP(cursor);
- mp = top->mp_page;
-
- DPRINTF("cursor_next: top page is %lu in cursor %p", mp->mp_pgno, (void *) cursor);
+ DPRINTF("cursor_next: top page is %zu in cursor %p", mp->mp_pgno, (void *) mc);
- if (top->mp_ki + 1 >= NUMKEYS(mp)) {
- DPRINTF("=====> move to next sibling page");
- if (mdb_sibling(cursor, 1) != MDB_SUCCESS) {
- cursor->mc_eof = 1;
+ if (mc->mc_ki[mc->mc_top] + 1u >= NUMKEYS(mp)) {
+ DPUTS("=====> move to next sibling page");
+ if (mdb_cursor_sibling(mc, 1) != MDB_SUCCESS) {
+ mc->mc_flags |= C_EOF;
+ mc->mc_flags &= ~C_INITIALIZED;
return MDB_NOTFOUND;
}
- top = CURSOR_TOP(cursor);
- mp = top->mp_page;
- DPRINTF("next page is %lu, key index %u", mp->mp_pgno, top->mp_ki);
+ mp = mc->mc_pg[mc->mc_top];
+ DPRINTF("next page is %zu, key index %u", mp->mp_pgno, mc->mc_ki[mc->mc_top]);
} else
- top->mp_ki++;
+ mc->mc_ki[mc->mc_top]++;
- DPRINTF("==> cursor points to page %lu with %u keys, key index %u",
- mp->mp_pgno, NUMKEYS(mp), top->mp_ki);
+ DPRINTF("==> cursor points to page %zu with %u keys, key index %u",
+ mp->mp_pgno, NUMKEYS(mp), mc->mc_ki[mc->mc_top]);
+
+ if (IS_LEAF2(mp)) {
+ key->mv_size = mc->mc_db->md_pad;
+ key->mv_data = LEAF2KEY(mp, mc->mc_ki[mc->mc_top], key->mv_size);
+ return MDB_SUCCESS;
+ }
assert(IS_LEAF(mp));
- leaf = NODEPTR(mp, top->mp_ki);
+ leaf = NODEPTR(mp, mc->mc_ki[mc->mc_top]);
+ if (F_ISSET(leaf->mn_flags, F_DUPDATA)) {
+ mdb_xcursor_init1(mc, leaf);
+ }
if (data) {
- if ((rc = mdb_read_data(cursor->mc_txn, leaf, data) != MDB_SUCCESS))
+ if ((rc = mdb_node_read(mc->mc_txn, leaf, data) != MDB_SUCCESS))
return rc;
- if (cursor->mc_txn->mt_dbs[cursor->mc_dbi].md_flags & MDB_DUPSORT) {
- mdb_xcursor_init1(cursor->mc_txn, cursor->mc_dbi, cursor->mc_xcursor, leaf);
- rc = mdb_cursor_first(&cursor->mc_xcursor->mx_cursor, data, NULL);
+ if (F_ISSET(leaf->mn_flags, F_DUPDATA)) {
+ rc = mdb_cursor_first(&mc->mc_xcursor->mx_cursor, data, NULL);
if (rc != MDB_SUCCESS)
return rc;
}
}
- return mdb_set_key(leaf, key);
+ MDB_SET_KEY(leaf, key);
+ return MDB_SUCCESS;
}
+/** Move the cursor to the previous data item. */
static int
-mdb_cursor_prev(MDB_cursor *cursor, MDB_val *key, MDB_val *data, MDB_cursor_op op)
+mdb_cursor_prev(MDB_cursor *mc, MDB_val *key, MDB_val *data, MDB_cursor_op op)
{
- MDB_ppage *top;
MDB_page *mp;
MDB_node *leaf;
int rc;
- assert(cursor->mc_initialized);
+ assert(mc->mc_flags & C_INITIALIZED);
+
+ mp = mc->mc_pg[mc->mc_top];
- if (cursor->mc_txn->mt_dbs[cursor->mc_dbi].md_flags & MDB_DUPSORT) {
+ if (mc->mc_db->md_flags & MDB_DUPSORT) {
+ leaf = NODEPTR(mp, mc->mc_ki[mc->mc_top]);
if (op == MDB_PREV || op == MDB_PREV_DUP) {
- rc = mdb_cursor_prev(&cursor->mc_xcursor->mx_cursor, data, NULL, MDB_PREV);
- if (op != MDB_PREV || rc == MDB_SUCCESS)
- return rc;
+ if (F_ISSET(leaf->mn_flags, F_DUPDATA)) {
+ rc = mdb_cursor_prev(&mc->mc_xcursor->mx_cursor, data, NULL, MDB_PREV);
+ if (op != MDB_PREV || rc == MDB_SUCCESS)
+ return rc;
+ } else {
+ mc->mc_xcursor->mx_cursor.mc_flags &= ~C_INITIALIZED;
+ if (op == MDB_PREV_DUP)
+ return MDB_NOTFOUND;
+ }
}
}
- top = CURSOR_TOP(cursor);
- mp = top->mp_page;
+ DPRINTF("cursor_prev: top page is %zu in cursor %p", mp->mp_pgno, (void *) mc);
- DPRINTF("cursor_prev: top page is %lu in cursor %p", mp->mp_pgno, (void *) cursor);
-
- if (top->mp_ki == 0) {
- DPRINTF("=====> move to prev sibling page");
- if (mdb_sibling(cursor, 0) != MDB_SUCCESS) {
+ if (mc->mc_ki[mc->mc_top] == 0) {
+ DPUTS("=====> move to prev sibling page");
+ if (mdb_cursor_sibling(mc, 0) != MDB_SUCCESS) {
+ mc->mc_flags &= ~C_INITIALIZED;
return MDB_NOTFOUND;
}
- top = CURSOR_TOP(cursor);
- mp = top->mp_page;
- top->mp_ki = NUMKEYS(mp) - 1;
- DPRINTF("prev page is %lu, key index %u", mp->mp_pgno, top->mp_ki);
+ mp = mc->mc_pg[mc->mc_top];
+ mc->mc_ki[mc->mc_top] = NUMKEYS(mp) - 1;
+ DPRINTF("prev page is %zu, key index %u", mp->mp_pgno, mc->mc_ki[mc->mc_top]);
} else
- top->mp_ki--;
+ mc->mc_ki[mc->mc_top]--;
+
+ mc->mc_flags &= ~C_EOF;
- cursor->mc_eof = 0;
+ DPRINTF("==> cursor points to page %zu with %u keys, key index %u",
+ mp->mp_pgno, NUMKEYS(mp), mc->mc_ki[mc->mc_top]);
- DPRINTF("==> cursor points to page %lu with %u keys, key index %u",
- mp->mp_pgno, NUMKEYS(mp), top->mp_ki);
+ if (IS_LEAF2(mp)) {
+ key->mv_size = mc->mc_db->md_pad;
+ key->mv_data = LEAF2KEY(mp, mc->mc_ki[mc->mc_top], key->mv_size);
+ return MDB_SUCCESS;
+ }
assert(IS_LEAF(mp));
- leaf = NODEPTR(mp, top->mp_ki);
+ leaf = NODEPTR(mp, mc->mc_ki[mc->mc_top]);
+ if (F_ISSET(leaf->mn_flags, F_DUPDATA)) {
+ mdb_xcursor_init1(mc, leaf);
+ }
if (data) {
- if ((rc = mdb_read_data(cursor->mc_txn, leaf, data) != MDB_SUCCESS))
+ if ((rc = mdb_node_read(mc->mc_txn, leaf, data) != MDB_SUCCESS))
return rc;
- if (cursor->mc_txn->mt_dbs[cursor->mc_dbi].md_flags & MDB_DUPSORT) {
- mdb_xcursor_init1(cursor->mc_txn, cursor->mc_dbi, cursor->mc_xcursor, leaf);
- rc = mdb_cursor_last(&cursor->mc_xcursor->mx_cursor, data, NULL);
+ if (F_ISSET(leaf->mn_flags, F_DUPDATA)) {
+ rc = mdb_cursor_last(&mc->mc_xcursor->mx_cursor, data, NULL);
if (rc != MDB_SUCCESS)
return rc;
}
}
- return mdb_set_key(leaf, key);
+ MDB_SET_KEY(leaf, key);
+ return MDB_SUCCESS;
}
+/** Set the cursor on a specific data item. */
static int
-mdb_cursor_set(MDB_cursor *cursor, MDB_val *key, MDB_val *data,
+mdb_cursor_set(MDB_cursor *mc, MDB_val *key, MDB_val *data,
MDB_cursor_op op, int *exactp)
{
int rc;
+ MDB_page *mp;
MDB_node *leaf;
- MDB_ppage *top;
- MDB_pageparent mpp;
+ DKBUF;
- assert(cursor);
+ assert(mc);
assert(key);
assert(key->mv_size > 0);
- while (CURSOR_TOP(cursor) != NULL)
- cursor_pop_page(cursor);
+ /* See if we're already on the right page */
+ if (mc->mc_flags & C_INITIALIZED) {
+ MDB_val nodekey;
+
+ mp = mc->mc_pg[mc->mc_top];
+ if (!NUMKEYS(mp)) {
+ mc->mc_ki[mc->mc_top] = 0;
+ return MDB_NOTFOUND;
+ }
+ if (mp->mp_flags & P_LEAF2) {
+ nodekey.mv_size = mc->mc_db->md_pad;
+ nodekey.mv_data = LEAF2KEY(mp, 0, nodekey.mv_size);
+ } else {
+ leaf = NODEPTR(mp, 0);
+ MDB_SET_KEY(leaf, &nodekey);
+ }
+ rc = mc->mc_dbx->md_cmp(key, &nodekey);
+ if (rc == 0) {
+ /* Probably happens rarely, but first node on the page
+ * was the one we wanted.
+ */
+ mc->mc_ki[mc->mc_top] = 0;
+ leaf = NODEPTR(mp, 0);
+ if (exactp)
+ *exactp = 1;
+ goto set1;
+ }
+ if (rc > 0) {
+ unsigned int i;
+ unsigned int nkeys = NUMKEYS(mp);
+ if (nkeys > 1) {
+ if (mp->mp_flags & P_LEAF2) {
+ nodekey.mv_data = LEAF2KEY(mp,
+ nkeys-1, nodekey.mv_size);
+ } else {
+ leaf = NODEPTR(mp, nkeys-1);
+ MDB_SET_KEY(leaf, &nodekey);
+ }
+ rc = mc->mc_dbx->md_cmp(key, &nodekey);
+ if (rc == 0) {
+ /* last node was the one we wanted */
+ mc->mc_ki[mc->mc_top] = nkeys-1;
+ leaf = NODEPTR(mp, nkeys-1);
+ if (exactp)
+ *exactp = 1;
+ goto set1;
+ }
+ if (rc < 0) {
+ /* This is definitely the right page, skip search_page */
+ rc = 0;
+ goto set2;
+ }
+ }
+ /* If any parents have right-sibs, search.
+ * Otherwise, there's nothing further.
+ */
+ for (i=0; i<mc->mc_top; i++)
+ if (mc->mc_ki[i] <
+ NUMKEYS(mc->mc_pg[i])-1)
+ break;
+ if (i == mc->mc_top) {
+ /* There are no other pages */
+ mc->mc_ki[mc->mc_top] = nkeys;
+ return MDB_NOTFOUND;
+ }
+ }
+ if (!mc->mc_top) {
+ /* There are no other pages */
+ mc->mc_ki[mc->mc_top] = 0;
+ return MDB_NOTFOUND;
+ }
+ }
- rc = mdb_search_page(cursor->mc_txn, cursor->mc_dbi, key, cursor, 0, &mpp);
+ rc = mdb_page_search(mc, key, 0);
if (rc != MDB_SUCCESS)
return rc;
- assert(IS_LEAF(mpp.mp_page));
- top = CURSOR_TOP(cursor);
- leaf = mdb_search_node(cursor->mc_txn, cursor->mc_dbi, mpp.mp_page, key, exactp, &top->mp_ki);
+ mp = mc->mc_pg[mc->mc_top];
+ assert(IS_LEAF(mp));
+
+set2:
+ leaf = mdb_node_search(mc, key, exactp);
if (exactp != NULL && !*exactp) {
/* MDB_SET specified and not an exact match. */
return MDB_NOTFOUND;
}
if (leaf == NULL) {
- DPRINTF("===> inexact leaf not found, goto sibling");
- if ((rc = mdb_sibling(cursor, 1)) != MDB_SUCCESS)
+ DPUTS("===> inexact leaf not found, goto sibling");
+ if ((rc = mdb_cursor_sibling(mc, 1)) != MDB_SUCCESS)
return rc; /* no entries matched */
- top = CURSOR_TOP(cursor);
- top->mp_ki = 0;
- mpp.mp_page = top->mp_page;
- assert(IS_LEAF(mpp.mp_page));
- leaf = NODEPTR(mpp.mp_page, 0);
+ mp = mc->mc_pg[mc->mc_top];
+ assert(IS_LEAF(mp));
+ leaf = NODEPTR(mp, 0);
}
- cursor->mc_initialized = 1;
- cursor->mc_eof = 0;
+set1:
+ mc->mc_flags |= C_INITIALIZED;
+ mc->mc_flags &= ~C_EOF;
- if (data) {
- if ((rc = mdb_read_data(cursor->mc_txn, leaf, data)) != MDB_SUCCESS)
- return rc;
+ if (IS_LEAF2(mp)) {
+ key->mv_size = mc->mc_db->md_pad;
+ key->mv_data = LEAF2KEY(mp, mc->mc_ki[mc->mc_top], key->mv_size);
+ return MDB_SUCCESS;
+ }
- if (cursor->mc_txn->mt_dbs[cursor->mc_dbi].md_flags & MDB_DUPSORT) {
- mdb_xcursor_init1(cursor->mc_txn, cursor->mc_dbi, cursor->mc_xcursor, leaf);
+ if (F_ISSET(leaf->mn_flags, F_DUPDATA)) {
+ mdb_xcursor_init1(mc, leaf);
+ }
+ if (data) {
+ if (F_ISSET(leaf->mn_flags, F_DUPDATA)) {
if (op == MDB_SET || op == MDB_SET_RANGE) {
- rc = mdb_cursor_first(&cursor->mc_xcursor->mx_cursor, data, NULL);
+ rc = mdb_cursor_first(&mc->mc_xcursor->mx_cursor, data, NULL);
} else {
int ex2, *ex2p;
- MDB_cursor_op op2;
if (op == MDB_GET_BOTH) {
ex2p = &ex2;
- op2 = MDB_SET;
+ ex2 = 0;
} else {
ex2p = NULL;
- op2 = MDB_SET_RANGE;
}
- rc = mdb_cursor_set(&cursor->mc_xcursor->mx_cursor, data, NULL, op2, ex2p);
+ rc = mdb_cursor_set(&mc->mc_xcursor->mx_cursor, data, NULL, MDB_SET_RANGE, ex2p);
if (rc != MDB_SUCCESS)
return rc;
}
+ } else if (op == MDB_GET_BOTH || op == MDB_GET_BOTH_RANGE) {
+ MDB_val d2;
+ if ((rc = mdb_node_read(mc->mc_txn, leaf, &d2)) != MDB_SUCCESS)
+ return rc;
+ rc = mc->mc_dbx->md_dcmp(data, &d2);
+ if (rc) {
+ if (op == MDB_GET_BOTH || rc > 0)
+ return MDB_NOTFOUND;
+ }
+
+ } else {
+ if (mc->mc_xcursor)
+ mc->mc_xcursor->mx_cursor.mc_flags &= ~C_INITIALIZED;
+ if ((rc = mdb_node_read(mc->mc_txn, leaf, data)) != MDB_SUCCESS)
+ return rc;
}
}
- rc = mdb_set_key(leaf, key);
- if (rc == MDB_SUCCESS) {
- DPRINTF("==> cursor placed on key %.*s",
- (int)key->mv_size, (char *)key->mv_data);
- ;
- }
+ /* The key already matches in all other cases */
+ if (op == MDB_SET_RANGE)
+ MDB_SET_KEY(leaf, key);
+ DPRINTF("==> cursor placed on key [%s]", DKEY(key));
return rc;
}
+/** Move the cursor to the first item in the database. */
static int
-mdb_cursor_first(MDB_cursor *cursor, MDB_val *key, MDB_val *data)
+mdb_cursor_first(MDB_cursor *mc, MDB_val *key, MDB_val *data)
{
int rc;
- MDB_pageparent mpp;
MDB_node *leaf;
- while (CURSOR_TOP(cursor) != NULL)
- cursor_pop_page(cursor);
+ if (!(mc->mc_flags & C_INITIALIZED) || mc->mc_top) {
+ rc = mdb_page_search(mc, NULL, 0);
+ if (rc != MDB_SUCCESS)
+ return rc;
+ }
+ assert(IS_LEAF(mc->mc_pg[mc->mc_top]));
+
+ leaf = NODEPTR(mc->mc_pg[mc->mc_top], 0);
+ mc->mc_flags |= C_INITIALIZED;
+ mc->mc_flags &= ~C_EOF;
- rc = mdb_search_page(cursor->mc_txn, cursor->mc_dbi, NULL, cursor, 0, &mpp);
- if (rc != MDB_SUCCESS)
- return rc;
- assert(IS_LEAF(mpp.mp_page));
+ mc->mc_ki[mc->mc_top] = 0;
- leaf = NODEPTR(mpp.mp_page, 0);
- cursor->mc_initialized = 1;
- cursor->mc_eof = 0;
+ if (IS_LEAF2(mc->mc_pg[mc->mc_top])) {
+ key->mv_size = mc->mc_db->md_pad;
+ key->mv_data = LEAF2KEY(mc->mc_pg[mc->mc_top], 0, key->mv_size);
+ return MDB_SUCCESS;
+ }
if (data) {
- if ((rc = mdb_read_data(cursor->mc_txn, leaf, data)) != MDB_SUCCESS)
- return rc;
-
- if (cursor->mc_txn->mt_dbs[cursor->mc_dbi].md_flags & MDB_DUPSORT) {
- mdb_xcursor_init1(cursor->mc_txn, cursor->mc_dbi, cursor->mc_xcursor, leaf);
- rc = mdb_cursor_first(&cursor->mc_xcursor->mx_cursor, data, NULL);
+ if (F_ISSET(leaf->mn_flags, F_DUPDATA)) {
+ mdb_xcursor_init1(mc, leaf);
+ rc = mdb_cursor_first(&mc->mc_xcursor->mx_cursor, data, NULL);
if (rc)
return rc;
+ } else {
+ if (mc->mc_xcursor)
+ mc->mc_xcursor->mx_cursor.mc_flags &= ~C_INITIALIZED;
+ if ((rc = mdb_node_read(mc->mc_txn, leaf, data)) != MDB_SUCCESS)
+ return rc;
}
}
- return mdb_set_key(leaf, key);
+ MDB_SET_KEY(leaf, key);
+ return MDB_SUCCESS;
}
+/** Move the cursor to the last item in the database. */
static int
-mdb_cursor_last(MDB_cursor *cursor, MDB_val *key, MDB_val *data)
+mdb_cursor_last(MDB_cursor *mc, MDB_val *key, MDB_val *data)
{
int rc;
- MDB_ppage *top;
- MDB_pageparent mpp;
MDB_node *leaf;
MDB_val lkey;
- while (CURSOR_TOP(cursor) != NULL)
- cursor_pop_page(cursor);
-
lkey.mv_size = MAXKEYSIZE+1;
lkey.mv_data = NULL;
- rc = mdb_search_page(cursor->mc_txn, cursor->mc_dbi, &lkey, cursor, 0, &mpp);
- if (rc != MDB_SUCCESS)
- return rc;
- assert(IS_LEAF(mpp.mp_page));
+ if (!(mc->mc_flags & C_INITIALIZED) || mc->mc_top) {
+ rc = mdb_page_search(mc, &lkey, 0);
+ if (rc != MDB_SUCCESS)
+ return rc;
+ }
+ assert(IS_LEAF(mc->mc_pg[mc->mc_top]));
- leaf = NODEPTR(mpp.mp_page, NUMKEYS(mpp.mp_page)-1);
- cursor->mc_initialized = 1;
- cursor->mc_eof = 0;
+ leaf = NODEPTR(mc->mc_pg[mc->mc_top], NUMKEYS(mc->mc_pg[mc->mc_top])-1);
+ mc->mc_flags |= C_INITIALIZED;
+ mc->mc_flags &= ~C_EOF;
- top = CURSOR_TOP(cursor);
- top->mp_ki = NUMKEYS(top->mp_page) - 1;
+ mc->mc_ki[mc->mc_top] = NUMKEYS(mc->mc_pg[mc->mc_top]) - 1;
- if (data) {
- if ((rc = mdb_read_data(cursor->mc_txn, leaf, data)) != MDB_SUCCESS)
- return rc;
+ if (IS_LEAF2(mc->mc_pg[mc->mc_top])) {
+ key->mv_size = mc->mc_db->md_pad;
+ key->mv_data = LEAF2KEY(mc->mc_pg[mc->mc_top], mc->mc_ki[mc->mc_top], key->mv_size);
+ return MDB_SUCCESS;
+ }
- if (cursor->mc_txn->mt_dbs[cursor->mc_dbi].md_flags & MDB_DUPSORT) {
- mdb_xcursor_init1(cursor->mc_txn, cursor->mc_dbi, cursor->mc_xcursor, leaf);
- rc = mdb_cursor_last(&cursor->mc_xcursor->mx_cursor, data, NULL);
+ if (data) {
+ if (F_ISSET(leaf->mn_flags, F_DUPDATA)) {
+ mdb_xcursor_init1(mc, leaf);
+ rc = mdb_cursor_last(&mc->mc_xcursor->mx_cursor, data, NULL);
if (rc)
return rc;
+ } else {
+ if (mc->mc_xcursor)
+ mc->mc_xcursor->mx_cursor.mc_flags &= ~C_INITIALIZED;
+ if ((rc = mdb_node_read(mc->mc_txn, leaf, data)) != MDB_SUCCESS)
+ return rc;
}
}
- return mdb_set_key(leaf, key);
+ MDB_SET_KEY(leaf, key);
+ return MDB_SUCCESS;
}
int
-mdb_cursor_get(MDB_cursor *cursor, MDB_val *key, MDB_val *data,
+mdb_cursor_get(MDB_cursor *mc, MDB_val *key, MDB_val *data,
MDB_cursor_op op)
{
int rc;
int exact = 0;
- assert(cursor);
+ assert(mc);
switch (op) {
case MDB_GET_BOTH:
case MDB_GET_BOTH_RANGE:
- if (data == NULL) {
+ if (data == NULL || mc->mc_xcursor == NULL) {
rc = EINVAL;
break;
}
case MDB_SET_RANGE:
if (key == NULL || key->mv_size == 0 || key->mv_size > MAXKEYSIZE) {
rc = EINVAL;
- } else if (op != MDB_SET_RANGE)
- rc = mdb_cursor_set(cursor, key, data, op, NULL);
+ } else if (op == MDB_SET_RANGE)
+ rc = mdb_cursor_set(mc, key, data, op, NULL);
+ else
+ rc = mdb_cursor_set(mc, key, data, op, &exact);
+ break;
+ case MDB_GET_MULTIPLE:
+ if (data == NULL ||
+ !(mc->mc_db->md_flags & MDB_DUPFIXED) ||
+ !(mc->mc_flags & C_INITIALIZED)) {
+ rc = EINVAL;
+ break;
+ }
+ rc = MDB_SUCCESS;
+ if (!(mc->mc_xcursor->mx_cursor.mc_flags & C_INITIALIZED) ||
+ (mc->mc_xcursor->mx_cursor.mc_flags & C_EOF))
+ break;
+ goto fetchm;
+ case MDB_NEXT_MULTIPLE:
+ if (data == NULL ||
+ !(mc->mc_db->md_flags & MDB_DUPFIXED)) {
+ rc = EINVAL;
+ break;
+ }
+ if (!(mc->mc_flags & C_INITIALIZED))
+ rc = mdb_cursor_first(mc, key, data);
else
- rc = mdb_cursor_set(cursor, key, data, op, &exact);
+ rc = mdb_cursor_next(mc, key, data, MDB_NEXT_DUP);
+ if (rc == MDB_SUCCESS) {
+ if (mc->mc_xcursor->mx_cursor.mc_flags & C_INITIALIZED) {
+ MDB_cursor *mx;
+fetchm:
+ mx = &mc->mc_xcursor->mx_cursor;
+ data->mv_size = NUMKEYS(mx->mc_pg[mx->mc_top]) *
+ mx->mc_db->md_pad;
+ data->mv_data = METADATA(mx->mc_pg[mx->mc_top]);
+ mx->mc_ki[mx->mc_top] = NUMKEYS(mx->mc_pg[mx->mc_top])-1;
+ } else {
+ rc = MDB_NOTFOUND;
+ }
+ }
break;
case MDB_NEXT:
case MDB_NEXT_DUP:
case MDB_NEXT_NODUP:
- if (!cursor->mc_initialized)
- rc = mdb_cursor_first(cursor, key, data);
+ if (!(mc->mc_flags & C_INITIALIZED))
+ rc = mdb_cursor_first(mc, key, data);
else
- rc = mdb_cursor_next(cursor, key, data, op);
+ rc = mdb_cursor_next(mc, key, data, op);
break;
case MDB_PREV:
case MDB_PREV_DUP:
case MDB_PREV_NODUP:
- if (!cursor->mc_initialized || cursor->mc_eof)
- rc = mdb_cursor_last(cursor, key, data);
+ if (!(mc->mc_flags & C_INITIALIZED) || (mc->mc_flags & C_EOF))
+ rc = mdb_cursor_last(mc, key, data);
else
- rc = mdb_cursor_prev(cursor, key, data, op);
+ rc = mdb_cursor_prev(mc, key, data, op);
break;
case MDB_FIRST:
- rc = mdb_cursor_first(cursor, key, data);
+ rc = mdb_cursor_first(mc, key, data);
+ break;
+ case MDB_FIRST_DUP:
+ if (data == NULL ||
+ !(mc->mc_db->md_flags & MDB_DUPSORT) ||
+ !(mc->mc_flags & C_INITIALIZED) ||
+ !(mc->mc_xcursor->mx_cursor.mc_flags & C_INITIALIZED)) {
+ rc = EINVAL;
+ break;
+ }
+ rc = mdb_cursor_first(&mc->mc_xcursor->mx_cursor, data, NULL);
break;
case MDB_LAST:
- rc = mdb_cursor_last(cursor, key, data);
+ rc = mdb_cursor_last(mc, key, data);
+ break;
+ case MDB_LAST_DUP:
+ if (data == NULL ||
+ !(mc->mc_db->md_flags & MDB_DUPSORT) ||
+ !(mc->mc_flags & C_INITIALIZED) ||
+ !(mc->mc_xcursor->mx_cursor.mc_flags & C_INITIALIZED)) {
+ rc = EINVAL;
+ break;
+ }
+ rc = mdb_cursor_last(&mc->mc_xcursor->mx_cursor, data, NULL);
break;
default:
DPRINTF("unhandled/unimplemented cursor operation %u", op);
return rc;
}
-/* Allocate a page and initialize it
+/** Touch all the pages in the cursor stack.
+ * Makes sure all the pages are writable, before attempting a write operation.
+ * @param[in] mc The cursor to operate on.
*/
-static MDB_dpage *
-mdb_new_page(MDB_txn *txn, MDB_dbi dbi, uint32_t flags, int num)
+static int
+mdb_cursor_touch(MDB_cursor *mc)
{
- MDB_dpage *dp;
+ int rc;
- if ((dp = mdb_alloc_page(txn, NULL, 0, num)) == NULL)
- return NULL;
- DPRINTF("allocated new mpage %lu, page size %u",
- dp->p.mp_pgno, txn->mt_env->me_psize);
- dp->p.mp_flags = flags | P_DIRTY;
- dp->p.mp_lower = PAGEHDRSZ;
- dp->p.mp_upper = txn->mt_env->me_psize;
+ if (mc->mc_dbi > MAIN_DBI && !(*mc->mc_dbflag & DB_DIRTY)) {
+ MDB_cursor mc2;
+ mdb_cursor_init(&mc2, mc->mc_txn, MAIN_DBI, NULL);
+ rc = mdb_page_search(&mc2, &mc->mc_dbx->md_name, 1);
+ if (rc)
+ return rc;
+ *mc->mc_dbflag = DB_DIRTY;
+ }
+ for (mc->mc_top = 0; mc->mc_top < mc->mc_snum; mc->mc_top++) {
+ rc = mdb_page_touch(mc);
+ if (rc)
+ return rc;
+ }
+ mc->mc_top = mc->mc_snum-1;
+ return MDB_SUCCESS;
+}
+
+int
+mdb_cursor_put(MDB_cursor *mc, MDB_val *key, MDB_val *data,
+ unsigned int flags)
+{
+ MDB_node *leaf = NULL;
+ MDB_val xdata, *rdata, dkey;
+ MDB_page *fp;
+ MDB_db dummy;
+ int do_sub = 0;
+ unsigned int mcount = 0;
+ size_t nsize;
+ int rc, rc2;
+ MDB_pagebuf pbuf;
+ char dbuf[MAXKEYSIZE+1];
+ unsigned int nflags;
+ DKBUF;
+
+ if (F_ISSET(mc->mc_txn->mt_flags, MDB_TXN_RDONLY))
+ return EACCES;
+
+ DPRINTF("==> put db %u key [%s], size %zu, data size %zu",
+ mc->mc_dbi, DKEY(key), key ? key->mv_size:0, data->mv_size);
+
+ dkey.mv_size = 0;
+
+ if (flags == MDB_CURRENT) {
+ if (!(mc->mc_flags & C_INITIALIZED))
+ return EINVAL;
+ rc = MDB_SUCCESS;
+ } else if (mc->mc_db->md_root == P_INVALID) {
+ MDB_page *np;
+ /* new database, write a root leaf page */
+ DPUTS("allocating new root leaf page");
+ if ((np = mdb_page_new(mc, P_LEAF, 1)) == NULL) {
+ return ENOMEM;
+ }
+ mc->mc_snum = 0;
+ mdb_cursor_push(mc, np);
+ mc->mc_db->md_root = np->mp_pgno;
+ mc->mc_db->md_depth++;
+ *mc->mc_dbflag = DB_DIRTY;
+ if ((mc->mc_db->md_flags & (MDB_DUPSORT|MDB_DUPFIXED))
+ == MDB_DUPFIXED)
+ np->mp_flags |= P_LEAF2;
+ mc->mc_flags |= C_INITIALIZED;
+ rc = MDB_NOTFOUND;
+ goto top;
+ } else {
+ int exact = 0;
+ MDB_val d2;
+ rc = mdb_cursor_set(mc, key, &d2, MDB_SET, &exact);
+ if ((flags & MDB_NOOVERWRITE) && rc == 0) {
+ DPRINTF("duplicate key [%s]", DKEY(key));
+ *data = d2;
+ return MDB_KEYEXIST;
+ }
+ if (rc && rc != MDB_NOTFOUND)
+ return rc;
+ }
+
+ /* Cursor is positioned, now make sure all pages are writable */
+ rc2 = mdb_cursor_touch(mc);
+ if (rc2)
+ return rc2;
+
+top:
+ /* The key already exists */
+ if (rc == MDB_SUCCESS) {
+ /* there's only a key anyway, so this is a no-op */
+ if (IS_LEAF2(mc->mc_pg[mc->mc_top])) {
+ unsigned int ksize = mc->mc_db->md_pad;
+ if (key->mv_size != ksize)
+ return EINVAL;
+ if (flags == MDB_CURRENT) {
+ char *ptr = LEAF2KEY(mc->mc_pg[mc->mc_top], mc->mc_ki[mc->mc_top], ksize);
+ memcpy(ptr, key->mv_data, ksize);
+ }
+ return MDB_SUCCESS;
+ }
+
+ leaf = NODEPTR(mc->mc_pg[mc->mc_top], mc->mc_ki[mc->mc_top]);
+
+ /* DB has dups? */
+ if (F_ISSET(mc->mc_db->md_flags, MDB_DUPSORT)) {
+ /* Was a single item before, must convert now */
+more:
+ if (!F_ISSET(leaf->mn_flags, F_DUPDATA)) {
+ /* Just overwrite the current item */
+ if (flags == MDB_CURRENT)
+ goto current;
+
+ dkey.mv_size = NODEDSZ(leaf);
+ dkey.mv_data = NODEDATA(leaf);
+#if UINT_MAX < SIZE_MAX
+ if (mc->mc_dbx->md_dcmp == mdb_cmp_int && dkey.mv_size == sizeof(size_t))
+#ifdef MISALIGNED_OK
+ mc->mc_dbx->md_dcmp = mdb_cmp_long;
+#else
+ mc->mc_dbx->md_dcmp = mdb_cmp_cint;
+#endif
+#endif
+ /* if data matches, ignore it */
+ if (!mc->mc_dbx->md_dcmp(data, &dkey))
+ return (flags == MDB_NODUPDATA) ? MDB_KEYEXIST : MDB_SUCCESS;
+
+ /* create a fake page for the dup items */
+ memcpy(dbuf, dkey.mv_data, dkey.mv_size);
+ dkey.mv_data = dbuf;
+ fp = (MDB_page *)&pbuf;
+ fp->mp_pgno = mc->mc_pg[mc->mc_top]->mp_pgno;
+ fp->mp_flags = P_LEAF|P_DIRTY|P_SUBP;
+ fp->mp_lower = PAGEHDRSZ;
+ fp->mp_upper = PAGEHDRSZ + dkey.mv_size + data->mv_size;
+ if (mc->mc_db->md_flags & MDB_DUPFIXED) {
+ fp->mp_flags |= P_LEAF2;
+ fp->mp_pad = data->mv_size;
+ } else {
+ fp->mp_upper += 2 * sizeof(indx_t) + 2 * NODESIZE +
+ (dkey.mv_size & 1) + (data->mv_size & 1);
+ }
+ mdb_node_del(mc->mc_pg[mc->mc_top], mc->mc_ki[mc->mc_top], 0);
+ do_sub = 1;
+ rdata = &xdata;
+ xdata.mv_size = fp->mp_upper;
+ xdata.mv_data = fp;
+ flags |= F_DUPDATA;
+ goto new_sub;
+ }
+ if (!F_ISSET(leaf->mn_flags, F_SUBDATA)) {
+ /* See if we need to convert from fake page to subDB */
+ MDB_page *mp;
+ unsigned int offset;
+ unsigned int i;
+
+ fp = NODEDATA(leaf);
+ if (flags == MDB_CURRENT) {
+ fp->mp_flags |= P_DIRTY;
+ COPY_PGNO(fp->mp_pgno, mc->mc_pg[mc->mc_top]->mp_pgno);
+ mc->mc_xcursor->mx_cursor.mc_pg[0] = fp;
+ flags |= F_DUPDATA;
+ goto put_sub;
+ }
+ if (mc->mc_db->md_flags & MDB_DUPFIXED) {
+ offset = fp->mp_pad;
+ } else {
+ offset = NODESIZE + sizeof(indx_t) + data->mv_size;
+ }
+ offset += offset & 1;
+ if (NODESIZE + sizeof(indx_t) + NODEKSZ(leaf) + NODEDSZ(leaf) +
+ offset >= (mc->mc_txn->mt_env->me_psize - PAGEHDRSZ) /
+ MDB_MINKEYS) {
+ /* yes, convert it */
+ dummy.md_flags = 0;
+ if (mc->mc_db->md_flags & MDB_DUPFIXED) {
+ dummy.md_pad = fp->mp_pad;
+ dummy.md_flags = MDB_DUPFIXED;
+ if (mc->mc_db->md_flags & MDB_INTEGERDUP)
+ dummy.md_flags |= MDB_INTEGERKEY;
+ }
+ dummy.md_depth = 1;
+ dummy.md_branch_pages = 0;
+ dummy.md_leaf_pages = 1;
+ dummy.md_overflow_pages = 0;
+ dummy.md_entries = NUMKEYS(fp);
+ rdata = &xdata;
+ xdata.mv_size = sizeof(MDB_db);
+ xdata.mv_data = &dummy;
+ mp = mdb_page_alloc(mc, 1);
+ if (!mp)
+ return ENOMEM;
+ offset = mc->mc_txn->mt_env->me_psize - NODEDSZ(leaf);
+ flags |= F_DUPDATA|F_SUBDATA;
+ dummy.md_root = mp->mp_pgno;
+ } else {
+ /* no, just grow it */
+ rdata = &xdata;
+ xdata.mv_size = NODEDSZ(leaf) + offset;
+ xdata.mv_data = &pbuf;
+ mp = (MDB_page *)&pbuf;
+ mp->mp_pgno = mc->mc_pg[mc->mc_top]->mp_pgno;
+ flags |= F_DUPDATA;
+ }
+ mp->mp_flags = fp->mp_flags | P_DIRTY;
+ mp->mp_pad = fp->mp_pad;
+ mp->mp_lower = fp->mp_lower;
+ mp->mp_upper = fp->mp_upper + offset;
+ if (IS_LEAF2(fp)) {
+ memcpy(METADATA(mp), METADATA(fp), NUMKEYS(fp) * fp->mp_pad);
+ } else {
+ nsize = NODEDSZ(leaf) - fp->mp_upper;
+ memcpy((char *)mp + mp->mp_upper, (char *)fp + fp->mp_upper, nsize);
+ for (i=0; i<NUMKEYS(fp); i++)
+ mp->mp_ptrs[i] = fp->mp_ptrs[i] + offset;
+ }
+ mdb_node_del(mc->mc_pg[mc->mc_top], mc->mc_ki[mc->mc_top], 0);
+ do_sub = 1;
+ goto new_sub;
+ }
+ /* data is on sub-DB, just store it */
+ flags |= F_DUPDATA|F_SUBDATA;
+ goto put_sub;
+ }
+current:
+ /* overflow page overwrites need special handling */
+ if (F_ISSET(leaf->mn_flags, F_BIGDATA)) {
+ MDB_page *omp;
+ pgno_t pg;
+ int ovpages, dpages;
+
+ ovpages = OVPAGES(NODEDSZ(leaf), mc->mc_txn->mt_env->me_psize);
+ dpages = OVPAGES(data->mv_size, mc->mc_txn->mt_env->me_psize);
+ memcpy(&pg, NODEDATA(leaf), sizeof(pg));
+ mdb_page_get(mc->mc_txn, pg, &omp);
+ /* Is the ov page writable and large enough? */
+ if ((omp->mp_flags & P_DIRTY) && ovpages >= dpages) {
+ /* yes, overwrite it. Note in this case we don't
+ * bother to try shrinking the node if the new data
+ * is smaller than the overflow threshold.
+ */
+ if (F_ISSET(flags, MDB_RESERVE))
+ data->mv_data = METADATA(omp);
+ else
+ memcpy(METADATA(omp), data->mv_data, data->mv_size);
+ goto done;
+ } else {
+ /* no, free ovpages */
+ int i;
+ mc->mc_db->md_overflow_pages -= ovpages;
+ for (i=0; i<ovpages; i++) {
+ DPRINTF("freed ov page %zu", pg);
+ mdb_midl_append(&mc->mc_txn->mt_free_pgs, pg);
+ pg++;
+ }
+ }
+ } else if (NODEDSZ(leaf) == data->mv_size) {
+ /* same size, just replace it. Note that we could
+ * also reuse this node if the new data is smaller,
+ * but instead we opt to shrink the node in that case.
+ */
+ if (F_ISSET(flags, MDB_RESERVE))
+ data->mv_data = NODEDATA(leaf);
+ else
+ memcpy(NODEDATA(leaf), data->mv_data, data->mv_size);
+ goto done;
+ }
+ mdb_node_del(mc->mc_pg[mc->mc_top], mc->mc_ki[mc->mc_top], 0);
+ mc->mc_db->md_entries--;
+ } else {
+ DPRINTF("inserting key at index %i", mc->mc_ki[mc->mc_top]);
+ }
+
+ rdata = data;
+
+new_sub:
+ nflags = flags & NODE_ADD_FLAGS;
+ nsize = IS_LEAF2(mc->mc_pg[mc->mc_top]) ? key->mv_size : mdb_leaf_size(mc->mc_txn->mt_env, key, rdata);
+ if (SIZELEFT(mc->mc_pg[mc->mc_top]) < nsize) {
+ if (( flags & (F_DUPDATA|F_SUBDATA)) == F_DUPDATA )
+ nflags &= ~MDB_APPEND;
+ rc = mdb_page_split(mc, key, rdata, P_INVALID, nflags);
+ } else {
+ /* There is room already in this leaf page. */
+ rc = mdb_node_add(mc, mc->mc_ki[mc->mc_top], key, rdata, 0, nflags);
+ if (rc == 0 && !do_sub) {
+ /* Adjust other cursors pointing to mp */
+ MDB_cursor *m2, *m3;
+ MDB_dbi dbi = mc->mc_dbi;
+ unsigned i = mc->mc_top;
+ MDB_page *mp = mc->mc_pg[i];
+
+ if (mc->mc_flags & C_SUB)
+ dbi--;
+
+ for (m2 = mc->mc_txn->mt_cursors[dbi]; m2; m2=m2->mc_next) {
+ if (mc->mc_flags & C_SUB)
+ m3 = &m2->mc_xcursor->mx_cursor;
+ else
+ m3 = m2;
+ if (m3 == mc || m3->mc_snum < mc->mc_snum) continue;
+ if (m3->mc_pg[i] == mp && m3->mc_ki[i] >= mc->mc_ki[i]) {
+ m3->mc_ki[i]++;
+ }
+ }
+ }
+ }
+
+ if (rc != MDB_SUCCESS)
+ mc->mc_txn->mt_flags |= MDB_TXN_ERROR;
+ else {
+ /* Now store the actual data in the child DB. Note that we're
+ * storing the user data in the keys field, so there are strict
+ * size limits on dupdata. The actual data fields of the child
+ * DB are all zero size.
+ */
+ if (do_sub) {
+ int xflags;
+put_sub:
+ xdata.mv_size = 0;
+ xdata.mv_data = "";
+ leaf = NODEPTR(mc->mc_pg[mc->mc_top], mc->mc_ki[mc->mc_top]);
+ if (flags & MDB_CURRENT) {
+ xflags = MDB_CURRENT;
+ } else {
+ mdb_xcursor_init1(mc, leaf);
+ xflags = (flags & MDB_NODUPDATA) ? MDB_NOOVERWRITE : 0;
+ }
+ /* converted, write the original data first */
+ if (dkey.mv_size) {
+ rc = mdb_cursor_put(&mc->mc_xcursor->mx_cursor, &dkey, &xdata, xflags);
+ if (rc)
+ return rc;
+ {
+ /* Adjust other cursors pointing to mp */
+ MDB_cursor *m2;
+ unsigned i = mc->mc_top;
+ MDB_page *mp = mc->mc_pg[i];
+
+ for (m2 = mc->mc_txn->mt_cursors[mc->mc_dbi]; m2; m2=m2->mc_next) {
+ if (m2 == mc || m2->mc_snum < mc->mc_snum) continue;
+ if (m2->mc_pg[i] == mp && m2->mc_ki[i] == mc->mc_ki[i]) {
+ mdb_xcursor_init1(m2, leaf);
+ }
+ }
+ }
+ }
+ xflags |= (flags & MDB_APPEND);
+ rc = mdb_cursor_put(&mc->mc_xcursor->mx_cursor, data, &xdata, xflags);
+ if (flags & F_SUBDATA) {
+ void *db = NODEDATA(leaf);
+ memcpy(db, &mc->mc_xcursor->mx_db, sizeof(MDB_db));
+ }
+ }
+ /* sub-writes might have failed so check rc again.
+ * Don't increment count if we just replaced an existing item.
+ */
+ if (!rc && !(flags & MDB_CURRENT))
+ mc->mc_db->md_entries++;
+ if (flags & MDB_MULTIPLE) {
+ mcount++;
+ if (mcount < data[1].mv_size) {
+ data[0].mv_data = (char *)data[0].mv_data + data[0].mv_size;
+ leaf = NODEPTR(mc->mc_pg[mc->mc_top], mc->mc_ki[mc->mc_top]);
+ goto more;
+ }
+ }
+ }
+done:
+ return rc;
+}
+
+int
+mdb_cursor_del(MDB_cursor *mc, unsigned int flags)
+{
+ MDB_node *leaf;
+ int rc;
+
+ if (F_ISSET(mc->mc_txn->mt_flags, MDB_TXN_RDONLY))
+ return EACCES;
+
+ if (!mc->mc_flags & C_INITIALIZED)
+ return EINVAL;
+
+ rc = mdb_cursor_touch(mc);
+ if (rc)
+ return rc;
+
+ leaf = NODEPTR(mc->mc_pg[mc->mc_top], mc->mc_ki[mc->mc_top]);
+
+ if (!IS_LEAF2(mc->mc_pg[mc->mc_top]) && F_ISSET(leaf->mn_flags, F_DUPDATA)) {
+ if (flags != MDB_NODUPDATA) {
+ if (!F_ISSET(leaf->mn_flags, F_SUBDATA)) {
+ mc->mc_xcursor->mx_cursor.mc_pg[0] = NODEDATA(leaf);
+ }
+ rc = mdb_cursor_del(&mc->mc_xcursor->mx_cursor, 0);
+ /* If sub-DB still has entries, we're done */
+ if (mc->mc_xcursor->mx_db.md_entries) {
+ if (leaf->mn_flags & F_SUBDATA) {
+ /* update subDB info */
+ void *db = NODEDATA(leaf);
+ memcpy(db, &mc->mc_xcursor->mx_db, sizeof(MDB_db));
+ } else {
+ /* shrink fake page */
+ mdb_node_shrink(mc->mc_pg[mc->mc_top], mc->mc_ki[mc->mc_top]);
+ }
+ mc->mc_db->md_entries--;
+ return rc;
+ }
+ /* otherwise fall thru and delete the sub-DB */
+ }
+
+ if (leaf->mn_flags & F_SUBDATA) {
+ /* add all the child DB's pages to the free list */
+ rc = mdb_drop0(&mc->mc_xcursor->mx_cursor, 0);
+ if (rc == MDB_SUCCESS) {
+ mc->mc_db->md_entries -=
+ mc->mc_xcursor->mx_db.md_entries;
+ }
+ }
+ }
+
+ return mdb_cursor_del0(mc, leaf);
+}
+
+/** Allocate and initialize new pages for a database.
+ * @param[in] mc a cursor on the database being added to.
+ * @param[in] flags flags defining what type of page is being allocated.
+ * @param[in] num the number of pages to allocate. This is usually 1,
+ * unless allocating overflow pages for a large record.
+ * @return Address of a page, or NULL on failure.
+ */
+static MDB_page *
+mdb_page_new(MDB_cursor *mc, uint32_t flags, int num)
+{
+ MDB_page *np;
- if (IS_BRANCH(&dp->p))
- txn->mt_dbs[dbi].md_branch_pages++;
- else if (IS_LEAF(&dp->p))
- txn->mt_dbs[dbi].md_leaf_pages++;
- else if (IS_OVERFLOW(&dp->p)) {
- txn->mt_dbs[dbi].md_overflow_pages += num;
- dp->p.mp_pages = num;
+ if ((np = mdb_page_alloc(mc, num)) == NULL)
+ return NULL;
+ DPRINTF("allocated new mpage %zu, page size %u",
+ np->mp_pgno, mc->mc_txn->mt_env->me_psize);
+ np->mp_flags = flags | P_DIRTY;
+ np->mp_lower = PAGEHDRSZ;
+ np->mp_upper = mc->mc_txn->mt_env->me_psize;
+
+ if (IS_BRANCH(np))
+ mc->mc_db->md_branch_pages++;
+ else if (IS_LEAF(np))
+ mc->mc_db->md_leaf_pages++;
+ else if (IS_OVERFLOW(np)) {
+ mc->mc_db->md_overflow_pages += num;
+ np->mp_pages = num;
}
- return dp;
+ return np;
}
+/** Calculate the size of a leaf node.
+ * The size depends on the environment's page size; if a data item
+ * is too large it will be put onto an overflow page and the node
+ * size will only include the key and not the data. Sizes are always
+ * rounded up to an even number of bytes, to guarantee 2-byte alignment
+ * of the #MDB_node headers.
+ * @param[in] env The environment handle.
+ * @param[in] key The key for the node.
+ * @param[in] data The data for the node.
+ * @return The number of bytes needed to store the node.
+ */
static size_t
mdb_leaf_size(MDB_env *env, MDB_val *key, MDB_val *data)
{
size_t sz;
sz = LEAFSIZE(key, data);
- if (data->mv_size >= env->me_psize / MDB_MINKEYS) {
+ if (sz >= env->me_psize / MDB_MINKEYS) {
/* put on overflow page */
sz -= data->mv_size - sizeof(pgno_t);
}
+ sz += sz & 1;
return sz + sizeof(indx_t);
}
+/** Calculate the size of a branch node.
+ * The size should depend on the environment's page size but since
+ * we currently don't support spilling large keys onto overflow
+ * pages, it's simply the size of the #MDB_node header plus the
+ * size of the key. Sizes are always rounded up to an even number
+ * of bytes, to guarantee 2-byte alignment of the #MDB_node headers.
+ * @param[in] env The environment handle.
+ * @param[in] key The key for the node.
+ * @return The number of bytes needed to store the node.
+ */
static size_t
mdb_branch_size(MDB_env *env, MDB_val *key)
{
return sz + sizeof(indx_t);
}
+/** Add a node to the page pointed to by the cursor.
+ * @param[in] mc The cursor for this operation.
+ * @param[in] indx The index on the page where the new node should be added.
+ * @param[in] key The key for the new node.
+ * @param[in] data The data for the new node, if any.
+ * @param[in] pgno The page number, if adding a branch node.
+ * @param[in] flags Flags for the node.
+ * @return 0 on success, non-zero on failure. Possible errors are:
+ * <ul>
+ * <li>ENOMEM - failed to allocate overflow pages for the node.
+ * <li>ENOSPC - there is insufficient room in the page. This error
+ * should never happen since all callers already calculate the
+ * page's free space before calling this function.
+ * </ul>
+ */
static int
-mdb_add_node(MDB_txn *txn, MDB_dbi dbi, MDB_page *mp, indx_t indx,
- MDB_val *key, MDB_val *data, pgno_t pgno, uint8_t flags)
+mdb_node_add(MDB_cursor *mc, indx_t indx,
+ MDB_val *key, MDB_val *data, pgno_t pgno, unsigned int flags)
{
unsigned int i;
size_t node_size = NODESIZE;
indx_t ofs;
MDB_node *node;
- MDB_dpage *ofp = NULL; /* overflow page */
+ MDB_page *mp = mc->mc_pg[mc->mc_top];
+ MDB_page *ofp = NULL; /* overflow page */
+ DKBUF;
assert(mp->mp_upper >= mp->mp_lower);
- DPRINTF("add node [%.*s] to %s page %lu at index %i, key size %zu",
- key ? (int)key->mv_size : 0, key ? (char *)key->mv_data : NULL,
+ DPRINTF("add to %s %spage %zu index %i, data size %zu key size %zu [%s]",
IS_LEAF(mp) ? "leaf" : "branch",
- mp->mp_pgno, indx, key ? key->mv_size : 0);
+ IS_SUBP(mp) ? "sub-" : "",
+ mp->mp_pgno, indx, data ? data->mv_size : 0,
+ key ? key->mv_size : 0, key ? DKEY(key) : NULL);
+
+ if (IS_LEAF2(mp)) {
+ /* Move higher keys up one slot. */
+ int ksize = mc->mc_db->md_pad, dif;
+ char *ptr = LEAF2KEY(mp, indx, ksize);
+ dif = NUMKEYS(mp) - indx;
+ if (dif > 0)
+ memmove(ptr+ksize, ptr, dif*ksize);
+ /* insert new key */
+ memcpy(ptr, key->mv_data, ksize);
+
+ /* Just using these for counting */
+ mp->mp_lower += sizeof(indx_t);
+ mp->mp_upper -= ksize - sizeof(indx_t);
+ return MDB_SUCCESS;
+ }
if (key != NULL)
node_size += key->mv_size;
if (F_ISSET(flags, F_BIGDATA)) {
/* Data already on overflow page. */
node_size += sizeof(pgno_t);
- } else if (data->mv_size >= txn->mt_env->me_psize / MDB_MINKEYS) {
- int ovpages = OVPAGES(data->mv_size, txn->mt_env->me_psize);
+ } else if (node_size + data->mv_size >= mc->mc_txn->mt_env->me_psize / MDB_MINKEYS) {
+ int ovpages = OVPAGES(data->mv_size, mc->mc_txn->mt_env->me_psize);
/* Put data on overflow page. */
- DPRINTF("data size is %zu, put on overflow page",
- data->mv_size);
+ DPRINTF("data size is %zu, node would be %zu, put data on overflow page",
+ data->mv_size, node_size+data->mv_size);
node_size += sizeof(pgno_t);
- if ((ofp = mdb_new_page(txn, dbi, P_OVERFLOW, ovpages)) == NULL)
+ if ((ofp = mdb_page_new(mc, P_OVERFLOW, ovpages)) == NULL)
return ENOMEM;
- DPRINTF("allocated overflow page %lu", ofp->p.mp_pgno);
+ DPRINTF("allocated overflow page %zu", ofp->mp_pgno);
flags |= F_BIGDATA;
} else {
node_size += data->mv_size;
}
}
+ node_size += node_size & 1;
if (node_size + sizeof(indx_t) > SIZELEFT(mp)) {
- DPRINTF("not enough room in page %lu, got %u ptrs",
+ DPRINTF("not enough room in page %zu, got %u ptrs",
mp->mp_pgno, NUMKEYS(mp));
DPRINTF("upper - lower = %u - %u = %u", mp->mp_upper, mp->mp_lower,
mp->mp_upper - mp->mp_lower);
node->mn_ksize = (key == NULL) ? 0 : key->mv_size;
node->mn_flags = flags;
if (IS_LEAF(mp))
- node->mn_dsize = data->mv_size;
+ SETDSZ(node,data->mv_size);
else
- node->mn_pgno = pgno;
+ SETPGNO(node,pgno);
if (key)
memcpy(NODEKEY(node), key->mv_data, key->mv_size);
if (F_ISSET(flags, F_BIGDATA))
memcpy(node->mn_data + key->mv_size, data->mv_data,
sizeof(pgno_t));
+ else if (F_ISSET(flags, MDB_RESERVE))
+ data->mv_data = node->mn_data + key->mv_size;
else
memcpy(node->mn_data + key->mv_size, data->mv_data,
data->mv_size);
} else {
- memcpy(node->mn_data + key->mv_size, &ofp->p.mp_pgno,
+ memcpy(node->mn_data + key->mv_size, &ofp->mp_pgno,
sizeof(pgno_t));
- memcpy(METADATA(&ofp->p), data->mv_data, data->mv_size);
+ if (F_ISSET(flags, MDB_RESERVE))
+ data->mv_data = METADATA(ofp);
+ else
+ memcpy(METADATA(ofp), data->mv_data, data->mv_size);
}
}
return MDB_SUCCESS;
}
+/** Delete the specified node from a page.
+ * @param[in] mp The page to operate on.
+ * @param[in] indx The index of the node to delete.
+ * @param[in] ksize The size of a node. Only used if the page is
+ * part of a #MDB_DUPFIXED database.
+ */
static void
-mdb_del_node(MDB_page *mp, indx_t indx)
+mdb_node_del(MDB_page *mp, indx_t indx, int ksize)
{
unsigned int sz;
indx_t i, j, numkeys, ptr;
MDB_node *node;
char *base;
- DPRINTF("delete node %u on %s page %lu", indx,
- IS_LEAF(mp) ? "leaf" : "branch", mp->mp_pgno);
+#if MDB_DEBUG
+ {
+ pgno_t pgno;
+ COPY_PGNO(pgno, mp->mp_pgno);
+ DPRINTF("delete node %u on %s page %zu", indx,
+ IS_LEAF(mp) ? "leaf" : "branch", pgno);
+ }
+#endif
assert(indx < NUMKEYS(mp));
+ if (IS_LEAF2(mp)) {
+ int x = NUMKEYS(mp) - 1 - indx;
+ base = LEAF2KEY(mp, indx, ksize);
+ if (x)
+ memmove(base, base + ksize, x * ksize);
+ mp->mp_lower -= sizeof(indx_t);
+ mp->mp_upper += ksize - sizeof(indx_t);
+ return;
+ }
+
node = NODEPTR(mp, indx);
sz = NODESIZE + node->mn_ksize;
if (IS_LEAF(mp)) {
else
sz += NODEDSZ(node);
}
+ sz += sz & 1;
ptr = mp->mp_ptrs[indx];
numkeys = NUMKEYS(mp);
mp->mp_upper += sz;
}
+/** Compact the main page after deleting a node on a subpage.
+ * @param[in] mp The main page to operate on.
+ * @param[in] indx The index of the subpage on the main page.
+ */
static void
-mdb_xcursor_init0(MDB_txn *txn, MDB_dbi dbi, MDB_xcursor *mx)
-{
- MDB_dbi dbn;
-
- mx->mx_txn = *txn;
- mx->mx_txn.mt_dbxs = mx->mx_dbxs;
- mx->mx_txn.mt_dbs = mx->mx_dbs;
- mx->mx_dbxs[0] = txn->mt_dbxs[0];
- mx->mx_dbxs[1] = txn->mt_dbxs[1];
- if (dbi > 1) {
- mx->mx_dbxs[2] = txn->mt_dbxs[dbi];
- dbn = 2;
+mdb_node_shrink(MDB_page *mp, indx_t indx)
+{
+ MDB_node *node;
+ MDB_page *sp, *xp;
+ char *base;
+ int osize, nsize;
+ int delta;
+ indx_t i, numkeys, ptr;
+
+ node = NODEPTR(mp, indx);
+ sp = (MDB_page *)NODEDATA(node);
+ osize = NODEDSZ(node);
+
+ delta = sp->mp_upper - sp->mp_lower;
+ SETDSZ(node, osize - delta);
+ xp = (MDB_page *)((char *)sp + delta);
+
+ /* shift subpage upward */
+ if (IS_LEAF2(sp)) {
+ nsize = NUMKEYS(sp) * sp->mp_pad;
+ memmove(METADATA(xp), METADATA(sp), nsize);
} else {
- dbn = 1;
+ int i;
+ nsize = osize - sp->mp_upper;
+ numkeys = NUMKEYS(sp);
+ for (i=numkeys-1; i>=0; i--)
+ xp->mp_ptrs[i] = sp->mp_ptrs[i] - delta;
+ }
+ xp->mp_upper = sp->mp_lower;
+ xp->mp_lower = sp->mp_lower;
+ xp->mp_flags = sp->mp_flags;
+ xp->mp_pad = sp->mp_pad;
+ COPY_PGNO(xp->mp_pgno, mp->mp_pgno);
+
+ /* shift lower nodes upward */
+ ptr = mp->mp_ptrs[indx];
+ numkeys = NUMKEYS(mp);
+ for (i = 0; i < numkeys; i++) {
+ if (mp->mp_ptrs[i] <= ptr)
+ mp->mp_ptrs[i] += delta;
}
- mx->mx_dbxs[dbn+1].md_parent = dbn;
- mx->mx_dbxs[dbn+1].md_cmp = mx->mx_dbxs[dbn].md_dcmp;
- mx->mx_dbxs[dbn+1].md_rel = mx->mx_dbxs[dbn].md_rel;
- mx->mx_dbxs[dbn+1].md_dirty = 0;
- mx->mx_txn.mt_numdbs = dbn+2;
- SLIST_INIT(&mx->mx_cursor.mc_stack);
- mx->mx_cursor.mc_txn = &mx->mx_txn;
- mx->mx_cursor.mc_dbi = dbn+1;
+ base = (char *)mp + mp->mp_upper;
+ memmove(base + delta, base, ptr - mp->mp_upper + NODESIZE + NODEKSZ(node));
+ mp->mp_upper += delta;
+}
+
+/** Initial setup of a sorted-dups cursor.
+ * Sorted duplicates are implemented as a sub-database for the given key.
+ * The duplicate data items are actually keys of the sub-database.
+ * Operations on the duplicate data items are performed using a sub-cursor
+ * initialized when the sub-database is first accessed. This function does
+ * the preliminary setup of the sub-cursor, filling in the fields that
+ * depend only on the parent DB.
+ * @param[in] mc The main cursor whose sorted-dups cursor is to be initialized.
+ */
+static void
+mdb_xcursor_init0(MDB_cursor *mc)
+{
+ MDB_xcursor *mx = mc->mc_xcursor;
+
+ mx->mx_cursor.mc_xcursor = NULL;
+ mx->mx_cursor.mc_txn = mc->mc_txn;
+ mx->mx_cursor.mc_db = &mx->mx_db;
+ mx->mx_cursor.mc_dbx = &mx->mx_dbx;
+ mx->mx_cursor.mc_dbi = mc->mc_dbi+1;
+ mx->mx_cursor.mc_dbflag = &mx->mx_dbflag;
+ mx->mx_cursor.mc_snum = 0;
+ mx->mx_cursor.mc_top = 0;
+ mx->mx_cursor.mc_flags = C_SUB;
+ mx->mx_dbx.md_cmp = mc->mc_dbx->md_dcmp;
+ mx->mx_dbx.md_dcmp = NULL;
+ mx->mx_dbx.md_rel = mc->mc_dbx->md_rel;
}
+/** Final setup of a sorted-dups cursor.
+ * Sets up the fields that depend on the data from the main cursor.
+ * @param[in] mc The main cursor whose sorted-dups cursor is to be initialized.
+ * @param[in] node The data containing the #MDB_db record for the
+ * sorted-dup database.
+ */
static void
-mdb_xcursor_init1(MDB_txn *txn, MDB_dbi dbi, MDB_xcursor *mx, MDB_node *node)
-{
- MDB_db *db = NODEDATA(node);
- MDB_dbi dbn;
- mx->mx_dbs[0] = txn->mt_dbs[0];
- mx->mx_dbs[1] = txn->mt_dbs[1];
- if (dbi > 1) {
- mx->mx_dbs[2] = txn->mt_dbs[dbi];
- dbn = 3;
+mdb_xcursor_init1(MDB_cursor *mc, MDB_node *node)
+{
+ MDB_xcursor *mx = mc->mc_xcursor;
+
+ if (node->mn_flags & F_SUBDATA) {
+ memcpy(&mx->mx_db, NODEDATA(node), sizeof(MDB_db));
+ mx->mx_cursor.mc_snum = 0;
+ mx->mx_cursor.mc_flags = C_SUB;
} else {
- dbn = 2;
+ MDB_page *fp = NODEDATA(node);
+ mx->mx_db.md_pad = mc->mc_pg[mc->mc_top]->mp_pad;
+ mx->mx_db.md_flags = 0;
+ mx->mx_db.md_depth = 1;
+ mx->mx_db.md_branch_pages = 0;
+ mx->mx_db.md_leaf_pages = 1;
+ mx->mx_db.md_overflow_pages = 0;
+ mx->mx_db.md_entries = NUMKEYS(fp);
+ COPY_PGNO(mx->mx_db.md_root, fp->mp_pgno);
+ mx->mx_cursor.mc_snum = 1;
+ mx->mx_cursor.mc_flags = C_INITIALIZED|C_SUB;
+ mx->mx_cursor.mc_top = 0;
+ mx->mx_cursor.mc_pg[0] = fp;
+ mx->mx_cursor.mc_ki[0] = 0;
+ if (mc->mc_db->md_flags & MDB_DUPFIXED) {
+ mx->mx_db.md_flags = MDB_DUPFIXED;
+ mx->mx_db.md_pad = fp->mp_pad;
+ if (mc->mc_db->md_flags & MDB_INTEGERDUP)
+ mx->mx_db.md_flags |= MDB_INTEGERKEY;
+ }
}
- mx->mx_dbs[dbn] = *db;
- mx->mx_dbxs[dbn].md_name.mv_data = NODEKEY(node);
- mx->mx_dbxs[dbn].md_name.mv_size = node->mn_ksize;
- mx->mx_txn.mt_next_pgno = txn->mt_next_pgno;
- mx->mx_txn.mt_oldest = txn->mt_oldest;
- mx->mx_txn.mt_u = txn->mt_u;
+ DPRINTF("Sub-db %u for db %u root page %zu", mx->mx_cursor.mc_dbi, mc->mc_dbi,
+ mx->mx_db.md_root);
+ mx->mx_dbflag = (F_ISSET(mc->mc_pg[mc->mc_top]->mp_flags, P_DIRTY)) ?
+ DB_DIRTY : 0;
+ mx->mx_dbx.md_name.mv_data = NODEKEY(node);
+ mx->mx_dbx.md_name.mv_size = node->mn_ksize;
+#if UINT_MAX < SIZE_MAX
+ if (mx->mx_dbx.md_cmp == mdb_cmp_int && mx->mx_db.md_pad == sizeof(size_t))
+#ifdef MISALIGNED_OK
+ mx->mx_dbx.md_cmp = mdb_cmp_long;
+#else
+ mx->mx_dbx.md_cmp = mdb_cmp_cint;
+#endif
+#endif
}
+/** Initialize a cursor for a given transaction and database. */
static void
-mdb_xcursor_fini(MDB_txn *txn, MDB_dbi dbi, MDB_xcursor *mx)
+mdb_cursor_init(MDB_cursor *mc, MDB_txn *txn, MDB_dbi dbi, MDB_xcursor *mx)
{
- txn->mt_next_pgno = mx->mx_txn.mt_next_pgno;
- txn->mt_oldest = mx->mx_txn.mt_oldest;
- txn->mt_u = mx->mx_txn.mt_u;
- txn->mt_dbs[0] = mx->mx_dbs[0];
- txn->mt_dbs[1] = mx->mx_dbs[1];
- txn->mt_dbxs[0].md_dirty = mx->mx_dbxs[0].md_dirty;
- txn->mt_dbxs[1].md_dirty = mx->mx_dbxs[1].md_dirty;
- if (dbi > 1) {
- txn->mt_dbs[dbi] = mx->mx_dbs[2];
- txn->mt_dbxs[dbi].md_dirty = mx->mx_dbxs[2].md_dirty;
+ mc->mc_orig = NULL;
+ mc->mc_dbi = dbi;
+ mc->mc_txn = txn;
+ mc->mc_db = &txn->mt_dbs[dbi];
+ mc->mc_dbx = &txn->mt_dbxs[dbi];
+ mc->mc_dbflag = &txn->mt_dbflags[dbi];
+ mc->mc_snum = 0;
+ mc->mc_top = 0;
+ mc->mc_flags = 0;
+ if (txn->mt_dbs[dbi].md_flags & MDB_DUPSORT) {
+ assert(mx != NULL);
+ mc->mc_xcursor = mx;
+ mdb_xcursor_init0(mc);
+ } else {
+ mc->mc_xcursor = NULL;
}
}
int
mdb_cursor_open(MDB_txn *txn, MDB_dbi dbi, MDB_cursor **ret)
{
- MDB_cursor *cursor;
+ MDB_cursor *mc;
+ MDB_xcursor *mx = NULL;
size_t size = sizeof(MDB_cursor);
- if (txn == NULL || ret == NULL || !dbi || dbi >= txn->mt_numdbs)
+ if (txn == NULL || ret == NULL || dbi >= txn->mt_numdbs)
+ return EINVAL;
+
+ /* Allow read access to the freelist */
+ if (!dbi && !F_ISSET(txn->mt_flags, MDB_TXN_RDONLY))
return EINVAL;
if (txn->mt_dbs[dbi].md_flags & MDB_DUPSORT)
size += sizeof(MDB_xcursor);
- if ((cursor = calloc(1, size)) != NULL) {
- SLIST_INIT(&cursor->mc_stack);
- cursor->mc_dbi = dbi;
- cursor->mc_txn = txn;
+ if ((mc = malloc(size)) != NULL) {
if (txn->mt_dbs[dbi].md_flags & MDB_DUPSORT) {
- MDB_xcursor *mx = (MDB_xcursor *)(cursor + 1);
- cursor->mc_xcursor = mx;
- mdb_xcursor_init0(txn, dbi, mx);
+ mx = (MDB_xcursor *)(mc + 1);
+ }
+ mdb_cursor_init(mc, txn, dbi, mx);
+ if (txn->mt_cursors) {
+ mc->mc_next = txn->mt_cursors[dbi];
+ txn->mt_cursors[dbi] = mc;
}
+ mc->mc_flags |= C_ALLOCD;
} else {
return ENOMEM;
}
- *ret = cursor;
+ *ret = mc;
return MDB_SUCCESS;
}
/* Return the count of duplicate data items for the current key */
int
-mdb_cursor_count(MDB_cursor *mc, unsigned long *countp)
+mdb_cursor_count(MDB_cursor *mc, size_t *countp)
{
+ MDB_node *leaf;
+
if (mc == NULL || countp == NULL)
return EINVAL;
- if (!(mc->mc_txn->mt_dbs[mc->mc_dbi].md_flags & MDB_DUPSORT))
+ if (!(mc->mc_db->md_flags & MDB_DUPSORT))
return EINVAL;
- if (!mc->mc_xcursor->mx_cursor.mc_initialized)
- return EINVAL;
+ leaf = NODEPTR(mc->mc_pg[mc->mc_top], mc->mc_ki[mc->mc_top]);
+ if (!F_ISSET(leaf->mn_flags, F_DUPDATA)) {
+ *countp = 1;
+ } else {
+ if (!(mc->mc_xcursor->mx_cursor.mc_flags & C_INITIALIZED))
+ return EINVAL;
- *countp = mc->mc_xcursor->mx_txn.mt_dbs[mc->mc_xcursor->mx_cursor.mc_dbi].md_entries;
+ *countp = mc->mc_xcursor->mx_db.md_entries;
+ }
return MDB_SUCCESS;
}
void
-mdb_cursor_close(MDB_cursor *cursor)
+mdb_cursor_close(MDB_cursor *mc)
{
- if (cursor != NULL) {
- while(!CURSOR_EMPTY(cursor))
- cursor_pop_page(cursor);
- if (cursor->mc_txn->mt_dbs[cursor->mc_dbi].md_flags & MDB_DUPSORT) {
- mdb_xcursor_fini(cursor->mc_txn, cursor->mc_dbi, cursor->mc_xcursor);
- while(!CURSOR_EMPTY(&cursor->mc_xcursor->mx_cursor))
- cursor_pop_page(&cursor->mc_xcursor->mx_cursor);
+ if (mc != NULL) {
+ /* remove from txn, if tracked */
+ if (mc->mc_txn->mt_cursors) {
+ MDB_cursor **prev = &mc->mc_txn->mt_cursors[mc->mc_dbi];
+ while (*prev && *prev != mc) prev = &(*prev)->mc_next;
+ if (*prev == mc)
+ *prev = mc->mc_next;
}
-
- free(cursor);
+ if (mc->mc_flags & C_ALLOCD)
+ free(mc);
}
}
+MDB_txn *
+mdb_cursor_txn(MDB_cursor *mc)
+{
+ if (!mc) return NULL;
+ return mc->mc_txn;
+}
+
+MDB_dbi
+mdb_cursor_dbi(MDB_cursor *mc)
+{
+ if (!mc) return 0;
+ return mc->mc_dbi;
+}
+
+/** Replace the key for a node with a new key.
+ * @param[in] mp The page containing the node to operate on.
+ * @param[in] indx The index of the node to operate on.
+ * @param[in] key The new key to use.
+ * @return 0 on success, non-zero on failure.
+ */
static int
mdb_update_key(MDB_page *mp, indx_t indx, MDB_val *key)
{
- indx_t ptr, i, numkeys;
- int delta;
- size_t len;
MDB_node *node;
char *base;
+ size_t len;
+ int delta, delta0;
+ indx_t ptr, i, numkeys;
+ DKBUF;
node = NODEPTR(mp, indx);
ptr = mp->mp_ptrs[indx];
- DPRINTF("update key %u (ofs %u) [%.*s] to [%.*s] on page %lu",
- indx, ptr,
- (int)node->mn_ksize, (char *)NODEKEY(node),
- (int)key->mv_size, (char *)key->mv_data,
- mp->mp_pgno);
+#if MDB_DEBUG
+ {
+ MDB_val k2;
+ char kbuf2[(MAXKEYSIZE*2+1)];
+ k2.mv_data = NODEKEY(node);
+ k2.mv_size = node->mn_ksize;
+ DPRINTF("update key %u (ofs %u) [%s] to [%s] on page %zu",
+ indx, ptr,
+ mdb_dkey(&k2, kbuf2),
+ DKEY(key),
+ mp->mp_pgno);
+ }
+#endif
- delta = key->mv_size - node->mn_ksize;
+ delta0 = delta = key->mv_size - node->mn_ksize;
+
+ /* Must be 2-byte aligned. If new key is
+ * shorter by 1, the shift will be skipped.
+ */
+ delta += (delta & 1);
if (delta) {
if (delta > 0 && SIZELEFT(mp) < delta) {
DPRINTF("OUCH! Not enough room, delta = %d", delta);
mp->mp_upper -= delta;
node = NODEPTR(mp, indx);
- node->mn_ksize = key->mv_size;
}
- memcpy(NODEKEY(node), key->mv_data, key->mv_size);
+ /* But even if no shift was needed, update ksize */
+ if (delta0)
+ node->mn_ksize = key->mv_size;
+
+ if (key->mv_size)
+ memcpy(NODEKEY(node), key->mv_data, key->mv_size);
return MDB_SUCCESS;
}
-/* Move a node from src to dst.
+/** Move a node from csrc to cdst.
*/
static int
-mdb_move_node(MDB_txn *txn, MDB_dbi dbi, MDB_pageparent *src, indx_t srcindx,
- MDB_pageparent *dst, indx_t dstindx)
+mdb_node_move(MDB_cursor *csrc, MDB_cursor *cdst)
{
int rc;
MDB_node *srcnode;
MDB_val key, data;
+ pgno_t srcpg;
+ unsigned short flags;
- srcnode = NODEPTR(src->mp_page, srcindx);
- DPRINTF("moving %s node %u [%.*s] on page %lu to node %u on page %lu",
- IS_LEAF(src->mp_page) ? "leaf" : "branch",
- srcindx,
- (int)srcnode->mn_ksize, (char *)NODEKEY(srcnode),
- src->mp_page->mp_pgno,
- dstindx, dst->mp_page->mp_pgno);
+ DKBUF;
/* Mark src and dst as dirty. */
- if ((rc = mdb_touch(txn, src)) ||
- (rc = mdb_touch(txn, dst)))
- return rc;;
+ if ((rc = mdb_page_touch(csrc)) ||
+ (rc = mdb_page_touch(cdst)))
+ return rc;
+
+ if (IS_LEAF2(csrc->mc_pg[csrc->mc_top])) {
+ srcnode = NODEPTR(csrc->mc_pg[csrc->mc_top], 0); /* fake */
+ key.mv_size = csrc->mc_db->md_pad;
+ key.mv_data = LEAF2KEY(csrc->mc_pg[csrc->mc_top], csrc->mc_ki[csrc->mc_top], key.mv_size);
+ data.mv_size = 0;
+ data.mv_data = NULL;
+ srcpg = 0;
+ flags = 0;
+ } else {
+ srcnode = NODEPTR(csrc->mc_pg[csrc->mc_top], csrc->mc_ki[csrc->mc_top]);
+ assert(!((long)srcnode&1));
+ srcpg = NODEPGNO(srcnode);
+ flags = srcnode->mn_flags;
+ if (csrc->mc_ki[csrc->mc_top] == 0 && IS_BRANCH(csrc->mc_pg[csrc->mc_top])) {
+ unsigned int snum = csrc->mc_snum;
+ MDB_node *s2;
+ /* must find the lowest key below src */
+ mdb_page_search_root(csrc, NULL, 0);
+ s2 = NODEPTR(csrc->mc_pg[csrc->mc_top], 0);
+ key.mv_size = NODEKSZ(s2);
+ key.mv_data = NODEKEY(s2);
+ csrc->mc_snum = snum--;
+ csrc->mc_top = snum;
+ } else {
+ key.mv_size = NODEKSZ(srcnode);
+ key.mv_data = NODEKEY(srcnode);
+ }
+ data.mv_size = NODEDSZ(srcnode);
+ data.mv_data = NODEDATA(srcnode);
+ }
+ if (IS_BRANCH(cdst->mc_pg[cdst->mc_top]) && cdst->mc_ki[cdst->mc_top] == 0) {
+ unsigned int snum = cdst->mc_snum;
+ MDB_node *s2;
+ MDB_val bkey;
+ /* must find the lowest key below dst */
+ mdb_page_search_root(cdst, NULL, 0);
+ s2 = NODEPTR(cdst->mc_pg[cdst->mc_top], 0);
+ bkey.mv_size = NODEKSZ(s2);
+ bkey.mv_data = NODEKEY(s2);
+ cdst->mc_snum = snum--;
+ cdst->mc_top = snum;
+ rc = mdb_update_key(cdst->mc_pg[cdst->mc_top], 0, &bkey);
+ }
+
+ DPRINTF("moving %s node %u [%s] on page %zu to node %u on page %zu",
+ IS_LEAF(csrc->mc_pg[csrc->mc_top]) ? "leaf" : "branch",
+ csrc->mc_ki[csrc->mc_top],
+ DKEY(&key),
+ csrc->mc_pg[csrc->mc_top]->mp_pgno,
+ cdst->mc_ki[cdst->mc_top], cdst->mc_pg[cdst->mc_top]->mp_pgno);
/* Add the node to the destination page.
*/
- key.mv_size = srcnode->mn_ksize;
- key.mv_data = NODEKEY(srcnode);
- data.mv_size = NODEDSZ(srcnode);
- data.mv_data = NODEDATA(srcnode);
- rc = mdb_add_node(txn, dbi, dst->mp_page, dstindx, &key, &data, NODEPGNO(srcnode),
- srcnode->mn_flags);
+ rc = mdb_node_add(cdst, cdst->mc_ki[cdst->mc_top], &key, &data, srcpg, flags);
if (rc != MDB_SUCCESS)
return rc;
/* Delete the node from the source page.
*/
- mdb_del_node(src->mp_page, srcindx);
-
- /* Update the parent separators.
- */
- if (srcindx == 0 && src->mp_pi != 0) {
- DPRINTF("update separator for source page %lu to [%.*s]",
- src->mp_page->mp_pgno, (int)key.mv_size, (char *)key.mv_data);
- if ((rc = mdb_update_key(src->mp_parent, src->mp_pi,
- &key)) != MDB_SUCCESS)
- return rc;
- }
+ mdb_node_del(csrc->mc_pg[csrc->mc_top], csrc->mc_ki[csrc->mc_top], key.mv_size);
- if (srcindx == 0 && IS_BRANCH(src->mp_page)) {
- MDB_val nullkey;
- nullkey.mv_size = 0;
- assert(mdb_update_key(src->mp_page, 0, &nullkey) == MDB_SUCCESS);
+ {
+ /* Adjust other cursors pointing to mp */
+ MDB_cursor *m2, *m3;
+ MDB_dbi dbi = csrc->mc_dbi;
+ MDB_page *mp = csrc->mc_pg[csrc->mc_top];
+
+ if (csrc->mc_flags & C_SUB)
+ dbi--;
+
+ for (m2 = csrc->mc_txn->mt_cursors[dbi]; m2; m2=m2->mc_next) {
+ if (m2 == csrc) continue;
+ if (csrc->mc_flags & C_SUB)
+ m3 = &m2->mc_xcursor->mx_cursor;
+ else
+ m3 = m2;
+ if (m3->mc_pg[csrc->mc_top] == mp && m3->mc_ki[csrc->mc_top] ==
+ csrc->mc_ki[csrc->mc_top]) {
+ m3->mc_pg[csrc->mc_top] = cdst->mc_pg[cdst->mc_top];
+ m3->mc_ki[csrc->mc_top] = cdst->mc_ki[cdst->mc_top];
+ }
+ }
}
- if (dstindx == 0 && dst->mp_pi != 0) {
- DPRINTF("update separator for destination page %lu to [%.*s]",
- dst->mp_page->mp_pgno, (int)key.mv_size, (char *)key.mv_data);
- if ((rc = mdb_update_key(dst->mp_parent, dst->mp_pi,
- &key)) != MDB_SUCCESS)
- return rc;
+ /* Update the parent separators.
+ */
+ if (csrc->mc_ki[csrc->mc_top] == 0) {
+ if (csrc->mc_ki[csrc->mc_top-1] != 0) {
+ if (IS_LEAF2(csrc->mc_pg[csrc->mc_top])) {
+ key.mv_data = LEAF2KEY(csrc->mc_pg[csrc->mc_top], 0, key.mv_size);
+ } else {
+ srcnode = NODEPTR(csrc->mc_pg[csrc->mc_top], 0);
+ key.mv_size = NODEKSZ(srcnode);
+ key.mv_data = NODEKEY(srcnode);
+ }
+ DPRINTF("update separator for source page %zu to [%s]",
+ csrc->mc_pg[csrc->mc_top]->mp_pgno, DKEY(&key));
+ if ((rc = mdb_update_key(csrc->mc_pg[csrc->mc_top-1], csrc->mc_ki[csrc->mc_top-1],
+ &key)) != MDB_SUCCESS)
+ return rc;
+ }
+ if (IS_BRANCH(csrc->mc_pg[csrc->mc_top])) {
+ MDB_val nullkey;
+ nullkey.mv_size = 0;
+ rc = mdb_update_key(csrc->mc_pg[csrc->mc_top], 0, &nullkey);
+ assert(rc == MDB_SUCCESS);
+ }
}
- if (dstindx == 0 && IS_BRANCH(dst->mp_page)) {
- MDB_val nullkey;
- nullkey.mv_size = 0;
- assert(mdb_update_key(dst->mp_page, 0, &nullkey) == MDB_SUCCESS);
+ if (cdst->mc_ki[cdst->mc_top] == 0) {
+ if (cdst->mc_ki[cdst->mc_top-1] != 0) {
+ if (IS_LEAF2(csrc->mc_pg[csrc->mc_top])) {
+ key.mv_data = LEAF2KEY(cdst->mc_pg[cdst->mc_top], 0, key.mv_size);
+ } else {
+ srcnode = NODEPTR(cdst->mc_pg[cdst->mc_top], 0);
+ key.mv_size = NODEKSZ(srcnode);
+ key.mv_data = NODEKEY(srcnode);
+ }
+ DPRINTF("update separator for destination page %zu to [%s]",
+ cdst->mc_pg[cdst->mc_top]->mp_pgno, DKEY(&key));
+ if ((rc = mdb_update_key(cdst->mc_pg[cdst->mc_top-1], cdst->mc_ki[cdst->mc_top-1],
+ &key)) != MDB_SUCCESS)
+ return rc;
+ }
+ if (IS_BRANCH(cdst->mc_pg[cdst->mc_top])) {
+ MDB_val nullkey;
+ nullkey.mv_size = 0;
+ rc = mdb_update_key(cdst->mc_pg[cdst->mc_top], 0, &nullkey);
+ assert(rc == MDB_SUCCESS);
+ }
}
return MDB_SUCCESS;
}
+/** Merge one page into another.
+ * The nodes from the page pointed to by \b csrc will
+ * be copied to the page pointed to by \b cdst and then
+ * the \b csrc page will be freed.
+ * @param[in] csrc Cursor pointing to the source page.
+ * @param[in] cdst Cursor pointing to the destination page.
+ */
static int
-mdb_merge(MDB_txn *txn, MDB_dbi dbi, MDB_pageparent *src, MDB_pageparent *dst)
+mdb_page_merge(MDB_cursor *csrc, MDB_cursor *cdst)
{
int rc;
- indx_t i;
+ indx_t i, j;
MDB_node *srcnode;
MDB_val key, data;
- MDB_pageparent mpp;
- MDB_dhead *dh;
+ unsigned nkeys;
- DPRINTF("merging page %lu and %lu", src->mp_page->mp_pgno, dst->mp_page->mp_pgno);
+ DPRINTF("merging page %zu into %zu", csrc->mc_pg[csrc->mc_top]->mp_pgno,
+ cdst->mc_pg[cdst->mc_top]->mp_pgno);
- assert(txn != NULL);
- assert(src->mp_parent); /* can't merge root page */
- assert(dst->mp_parent);
+ assert(csrc->mc_snum > 1); /* can't merge root page */
+ assert(cdst->mc_snum > 1);
- /* Mark src and dst as dirty. */
- if ((rc = mdb_touch(txn, src)) ||
- (rc = mdb_touch(txn, dst)))
+ /* Mark dst as dirty. */
+ if ((rc = mdb_page_touch(cdst)))
return rc;
/* Move all nodes from src to dst.
*/
- for (i = 0; i < NUMKEYS(src->mp_page); i++) {
- srcnode = NODEPTR(src->mp_page, i);
+ j = nkeys = NUMKEYS(cdst->mc_pg[cdst->mc_top]);
+ if (IS_LEAF2(csrc->mc_pg[csrc->mc_top])) {
+ key.mv_size = csrc->mc_db->md_pad;
+ key.mv_data = METADATA(csrc->mc_pg[csrc->mc_top]);
+ for (i = 0; i < NUMKEYS(csrc->mc_pg[csrc->mc_top]); i++, j++) {
+ rc = mdb_node_add(cdst, j, &key, NULL, 0, 0);
+ if (rc != MDB_SUCCESS)
+ return rc;
+ key.mv_data = (char *)key.mv_data + key.mv_size;
+ }
+ } else {
+ for (i = 0; i < NUMKEYS(csrc->mc_pg[csrc->mc_top]); i++, j++) {
+ srcnode = NODEPTR(csrc->mc_pg[csrc->mc_top], i);
+ if (i == 0 && IS_BRANCH(csrc->mc_pg[csrc->mc_top])) {
+ unsigned int snum = csrc->mc_snum;
+ MDB_node *s2;
+ /* must find the lowest key below src */
+ mdb_page_search_root(csrc, NULL, 0);
+ s2 = NODEPTR(csrc->mc_pg[csrc->mc_top], 0);
+ key.mv_size = NODEKSZ(s2);
+ key.mv_data = NODEKEY(s2);
+ csrc->mc_snum = snum--;
+ csrc->mc_top = snum;
+ } else {
+ key.mv_size = srcnode->mn_ksize;
+ key.mv_data = NODEKEY(srcnode);
+ }
- key.mv_size = srcnode->mn_ksize;
- key.mv_data = NODEKEY(srcnode);
- data.mv_size = NODEDSZ(srcnode);
- data.mv_data = NODEDATA(srcnode);
- rc = mdb_add_node(txn, dbi, dst->mp_page, NUMKEYS(dst->mp_page), &key,
- &data, NODEPGNO(srcnode), srcnode->mn_flags);
- if (rc != MDB_SUCCESS)
- return rc;
+ data.mv_size = NODEDSZ(srcnode);
+ data.mv_data = NODEDATA(srcnode);
+ rc = mdb_node_add(cdst, j, &key, &data, NODEPGNO(srcnode), srcnode->mn_flags);
+ if (rc != MDB_SUCCESS)
+ return rc;
+ }
}
- DPRINTF("dst page %lu now has %u keys (%.1f%% filled)",
- dst->mp_page->mp_pgno, NUMKEYS(dst->mp_page), (float)PAGEFILL(txn->mt_env, dst->mp_page) / 10);
+ DPRINTF("dst page %zu now has %u keys (%.1f%% filled)",
+ cdst->mc_pg[cdst->mc_top]->mp_pgno, NUMKEYS(cdst->mc_pg[cdst->mc_top]), (float)PAGEFILL(cdst->mc_txn->mt_env, cdst->mc_pg[cdst->mc_top]) / 10);
- /* Unlink the src page from parent.
+ /* Unlink the src page from parent and add to free list.
*/
- mdb_del_node(src->mp_parent, src->mp_pi);
- if (src->mp_pi == 0) {
+ mdb_node_del(csrc->mc_pg[csrc->mc_top-1], csrc->mc_ki[csrc->mc_top-1], 0);
+ if (csrc->mc_ki[csrc->mc_top-1] == 0) {
key.mv_size = 0;
- if ((rc = mdb_update_key(src->mp_parent, 0, &key)) != MDB_SUCCESS)
+ if ((rc = mdb_update_key(csrc->mc_pg[csrc->mc_top-1], 0, &key)) != MDB_SUCCESS)
return rc;
}
- if (IS_LEAF(src->mp_page))
- txn->mt_dbs[dbi].md_leaf_pages--;
+ mdb_midl_append(&csrc->mc_txn->mt_free_pgs, csrc->mc_pg[csrc->mc_top]->mp_pgno);
+ if (IS_LEAF(csrc->mc_pg[csrc->mc_top]))
+ csrc->mc_db->md_leaf_pages--;
else
- txn->mt_dbs[dbi].md_branch_pages--;
+ csrc->mc_db->md_branch_pages--;
+ {
+ /* Adjust other cursors pointing to mp */
+ MDB_cursor *m2, *m3;
+ MDB_dbi dbi = csrc->mc_dbi;
+ MDB_page *mp = cdst->mc_pg[cdst->mc_top];
- mpp.mp_page = src->mp_parent;
- dh = (MDB_dhead *)src->mp_parent;
- dh--;
- mpp.mp_parent = dh->md_parent;
- mpp.mp_pi = dh->md_pi;
+ if (csrc->mc_flags & C_SUB)
+ dbi--;
+
+ for (m2 = csrc->mc_txn->mt_cursors[dbi]; m2; m2=m2->mc_next) {
+ if (csrc->mc_flags & C_SUB)
+ m3 = &m2->mc_xcursor->mx_cursor;
+ else
+ m3 = m2;
+ if (m3 == csrc) continue;
+ if (m3->mc_snum < csrc->mc_snum) continue;
+ if (m3->mc_pg[csrc->mc_top] == csrc->mc_pg[csrc->mc_top]) {
+ m3->mc_pg[csrc->mc_top] = mp;
+ m3->mc_ki[csrc->mc_top] += nkeys;
+ }
+ }
+ }
+ mdb_cursor_pop(csrc);
- return mdb_rebalance(txn, dbi, &mpp);
+ return mdb_rebalance(csrc);
}
-#define FILL_THRESHOLD 250
+/** Copy the contents of a cursor.
+ * @param[in] csrc The cursor to copy from.
+ * @param[out] cdst The cursor to copy to.
+ */
+static void
+mdb_cursor_copy(const MDB_cursor *csrc, MDB_cursor *cdst)
+{
+ unsigned int i;
+ cdst->mc_txn = csrc->mc_txn;
+ cdst->mc_dbi = csrc->mc_dbi;
+ cdst->mc_db = csrc->mc_db;
+ cdst->mc_dbx = csrc->mc_dbx;
+ cdst->mc_snum = csrc->mc_snum;
+ cdst->mc_top = csrc->mc_top;
+ cdst->mc_flags = csrc->mc_flags;
+
+ for (i=0; i<csrc->mc_snum; i++) {
+ cdst->mc_pg[i] = csrc->mc_pg[i];
+ cdst->mc_ki[i] = csrc->mc_ki[i];
+ }
+}
+
+/** Rebalance the tree after a delete operation.
+ * @param[in] mc Cursor pointing to the page where rebalancing
+ * should begin.
+ * @return 0 on success, non-zero on failure.
+ */
static int
-mdb_rebalance(MDB_txn *txn, MDB_dbi dbi, MDB_pageparent *mpp)
+mdb_rebalance(MDB_cursor *mc)
{
MDB_node *node;
- MDB_page *root;
- MDB_pageparent npp;
- indx_t si = 0, di = 0;
-
- assert(txn != NULL);
- assert(mpp != NULL);
+ int rc;
+ unsigned int ptop;
+ MDB_cursor mn;
- DPRINTF("rebalancing %s page %lu (has %u keys, %.1f%% full)",
- IS_LEAF(mpp->mp_page) ? "leaf" : "branch",
- mpp->mp_page->mp_pgno, NUMKEYS(mpp->mp_page), (float)PAGEFILL(txn->mt_env, mpp->mp_page) / 10);
+#if MDB_DEBUG
+ {
+ pgno_t pgno;
+ COPY_PGNO(pgno, mc->mc_pg[mc->mc_top]->mp_pgno);
+ DPRINTF("rebalancing %s page %zu (has %u keys, %.1f%% full)",
+ IS_LEAF(mc->mc_pg[mc->mc_top]) ? "leaf" : "branch",
+ pgno, NUMKEYS(mc->mc_pg[mc->mc_top]), (float)PAGEFILL(mc->mc_txn->mt_env, mc->mc_pg[mc->mc_top]) / 10);
+ }
+#endif
- if (PAGEFILL(txn->mt_env, mpp->mp_page) >= FILL_THRESHOLD) {
- DPRINTF("no need to rebalance page %lu, above fill threshold",
- mpp->mp_page->mp_pgno);
+ if (PAGEFILL(mc->mc_txn->mt_env, mc->mc_pg[mc->mc_top]) >= FILL_THRESHOLD) {
+#if MDB_DEBUG
+ pgno_t pgno;
+ COPY_PGNO(pgno, mc->mc_pg[mc->mc_top]->mp_pgno);
+ DPRINTF("no need to rebalance page %zu, above fill threshold",
+ pgno);
+#endif
return MDB_SUCCESS;
}
- if (mpp->mp_parent == NULL) {
- if (NUMKEYS(mpp->mp_page) == 0) {
- DPRINTF("tree is completely empty");
- txn->mt_dbs[dbi].md_root = P_INVALID;
- txn->mt_dbs[dbi].md_depth--;
- txn->mt_dbs[dbi].md_leaf_pages--;
- } else if (IS_BRANCH(mpp->mp_page) && NUMKEYS(mpp->mp_page) == 1) {
- DPRINTF("collapsing root page!");
- txn->mt_dbs[dbi].md_root = NODEPGNO(NODEPTR(mpp->mp_page, 0));
- if ((root = mdb_get_page(txn, txn->mt_dbs[dbi].md_root)) == NULL)
- return MDB_PAGE_NOTFOUND;
- txn->mt_dbs[dbi].md_depth--;
- txn->mt_dbs[dbi].md_branch_pages--;
+ if (mc->mc_snum < 2) {
+ MDB_page *mp = mc->mc_pg[0];
+ if (NUMKEYS(mp) == 0) {
+ DPUTS("tree is completely empty");
+ mc->mc_db->md_root = P_INVALID;
+ mc->mc_db->md_depth = 0;
+ mc->mc_db->md_leaf_pages = 0;
+ mdb_midl_append(&mc->mc_txn->mt_free_pgs, mp->mp_pgno);
+ mc->mc_snum = 0;
+ mc->mc_top = 0;
+ {
+ /* Adjust other cursors pointing to mp */
+ MDB_cursor *m2, *m3;
+ MDB_dbi dbi = mc->mc_dbi;
+
+ if (mc->mc_flags & C_SUB)
+ dbi--;
+
+ for (m2 = mc->mc_txn->mt_cursors[dbi]; m2; m2=m2->mc_next) {
+ if (m2 == mc) continue;
+ if (mc->mc_flags & C_SUB)
+ m3 = &m2->mc_xcursor->mx_cursor;
+ else
+ m3 = m2;
+ if (m3->mc_snum < mc->mc_snum) continue;
+ if (m3->mc_pg[0] == mp) {
+ m3->mc_snum = 0;
+ m3->mc_top = 0;
+ }
+ }
+ }
+ } else if (IS_BRANCH(mp) && NUMKEYS(mp) == 1) {
+ DPUTS("collapsing root page!");
+ mdb_midl_append(&mc->mc_txn->mt_free_pgs, mp->mp_pgno);
+ mc->mc_db->md_root = NODEPGNO(NODEPTR(mp, 0));
+ if ((rc = mdb_page_get(mc->mc_txn, mc->mc_db->md_root,
+ &mc->mc_pg[0])))
+ return rc;
+ mc->mc_db->md_depth--;
+ mc->mc_db->md_branch_pages--;
+ {
+ /* Adjust other cursors pointing to mp */
+ MDB_cursor *m2, *m3;
+ MDB_dbi dbi = mc->mc_dbi;
+
+ if (mc->mc_flags & C_SUB)
+ dbi--;
+
+ for (m2 = mc->mc_txn->mt_cursors[dbi]; m2; m2=m2->mc_next) {
+ if (m2 == mc) continue;
+ if (mc->mc_flags & C_SUB)
+ m3 = &m2->mc_xcursor->mx_cursor;
+ else
+ m3 = m2;
+ if (m3->mc_snum < mc->mc_snum) continue;
+ if (m3->mc_pg[0] == mp) {
+ m3->mc_pg[0] = mc->mc_pg[0];
+ }
+ }
+ }
} else
- DPRINTF("root page doesn't need rebalancing");
+ DPUTS("root page doesn't need rebalancing");
return MDB_SUCCESS;
}
/* The parent (branch page) must have at least 2 pointers,
* otherwise the tree is invalid.
*/
- assert(NUMKEYS(mpp->mp_parent) > 1);
+ ptop = mc->mc_top-1;
+ assert(NUMKEYS(mc->mc_pg[ptop]) > 1);
/* Leaf page fill factor is below the threshold.
* Try to move keys from left or right neighbor, or
/* Find neighbors.
*/
- if (mpp->mp_pi == 0) {
+ mdb_cursor_copy(mc, &mn);
+ mn.mc_xcursor = NULL;
+
+ if (mc->mc_ki[ptop] == 0) {
/* We're the leftmost leaf in our parent.
*/
- DPRINTF("reading right neighbor");
- node = NODEPTR(mpp->mp_parent, mpp->mp_pi + 1);
- if ((npp.mp_page = mdb_get_page(txn, NODEPGNO(node))) == NULL)
- return MDB_PAGE_NOTFOUND;
- npp.mp_pi = mpp->mp_pi + 1;
- si = 0;
- di = NUMKEYS(mpp->mp_page);
+ DPUTS("reading right neighbor");
+ mn.mc_ki[ptop]++;
+ node = NODEPTR(mc->mc_pg[ptop], mn.mc_ki[ptop]);
+ if ((rc = mdb_page_get(mc->mc_txn, NODEPGNO(node), &mn.mc_pg[mn.mc_top])))
+ return rc;
+ mn.mc_ki[mn.mc_top] = 0;
+ mc->mc_ki[mc->mc_top] = NUMKEYS(mc->mc_pg[mc->mc_top]);
} else {
/* There is at least one neighbor to the left.
*/
- DPRINTF("reading left neighbor");
- node = NODEPTR(mpp->mp_parent, mpp->mp_pi - 1);
- if ((npp.mp_page = mdb_get_page(txn, NODEPGNO(node))) == NULL)
- return MDB_PAGE_NOTFOUND;
- npp.mp_pi = mpp->mp_pi - 1;
- si = NUMKEYS(npp.mp_page) - 1;
- di = 0;
+ DPUTS("reading left neighbor");
+ mn.mc_ki[ptop]--;
+ node = NODEPTR(mc->mc_pg[ptop], mn.mc_ki[ptop]);
+ if ((rc = mdb_page_get(mc->mc_txn, NODEPGNO(node), &mn.mc_pg[mn.mc_top])))
+ return rc;
+ mn.mc_ki[mn.mc_top] = NUMKEYS(mn.mc_pg[mn.mc_top]) - 1;
+ mc->mc_ki[mc->mc_top] = 0;
}
- npp.mp_parent = mpp->mp_parent;
- DPRINTF("found neighbor page %lu (%u keys, %.1f%% full)",
- npp.mp_page->mp_pgno, NUMKEYS(npp.mp_page), (float)PAGEFILL(txn->mt_env, npp.mp_page) / 10);
+ DPRINTF("found neighbor page %zu (%u keys, %.1f%% full)",
+ mn.mc_pg[mn.mc_top]->mp_pgno, NUMKEYS(mn.mc_pg[mn.mc_top]), (float)PAGEFILL(mc->mc_txn->mt_env, mn.mc_pg[mn.mc_top]) / 10);
/* If the neighbor page is above threshold and has at least two
* keys, move one key from it.
*
* Otherwise we should try to merge them.
*/
- if (PAGEFILL(txn->mt_env, npp.mp_page) >= FILL_THRESHOLD && NUMKEYS(npp.mp_page) >= 2)
- return mdb_move_node(txn, dbi, &npp, si, mpp, di);
+ if (PAGEFILL(mc->mc_txn->mt_env, mn.mc_pg[mn.mc_top]) >= FILL_THRESHOLD && NUMKEYS(mn.mc_pg[mn.mc_top]) >= 2)
+ return mdb_node_move(&mn, mc);
else { /* FIXME: if (has_enough_room()) */
- if (mpp->mp_pi == 0)
- return mdb_merge(txn, dbi, &npp, mpp);
+ mc->mc_flags &= ~C_INITIALIZED;
+ if (mc->mc_ki[ptop] == 0)
+ return mdb_page_merge(&mn, mc);
else
- return mdb_merge(txn, dbi, mpp, &npp);
+ return mdb_page_merge(mc, &mn);
}
}
+/** Complete a delete operation started by #mdb_cursor_del(). */
static int
-mdb_del0(MDB_txn *txn, MDB_dbi dbi, unsigned int ki, MDB_pageparent *mpp, MDB_node *leaf)
+mdb_cursor_del0(MDB_cursor *mc, MDB_node *leaf)
{
int rc;
/* add overflow pages to free list */
- if (F_ISSET(leaf->mn_flags, F_BIGDATA)) {
+ if (!IS_LEAF2(mc->mc_pg[mc->mc_top]) && F_ISSET(leaf->mn_flags, F_BIGDATA)) {
int i, ovpages;
pgno_t pg;
memcpy(&pg, NODEDATA(leaf), sizeof(pg));
- ovpages = OVPAGES(NODEDSZ(leaf), txn->mt_env->me_psize);
+ ovpages = OVPAGES(NODEDSZ(leaf), mc->mc_txn->mt_env->me_psize);
+ mc->mc_db->md_overflow_pages -= ovpages;
for (i=0; i<ovpages; i++) {
- DPRINTF("freed ov page %lu", pg);
- mdb_midl_insert(txn->mt_free_pgs, pg);
+ DPRINTF("freed ov page %zu", pg);
+ mdb_midl_append(&mc->mc_txn->mt_free_pgs, pg);
pg++;
}
}
- mdb_del_node(mpp->mp_page, ki);
- txn->mt_dbs[dbi].md_entries--;
- rc = mdb_rebalance(txn, dbi, mpp);
+ mdb_node_del(mc->mc_pg[mc->mc_top], mc->mc_ki[mc->mc_top], mc->mc_db->md_pad);
+ mc->mc_db->md_entries--;
+ rc = mdb_rebalance(mc);
if (rc != MDB_SUCCESS)
- txn->mt_flags |= MDB_TXN_ERROR;
+ mc->mc_txn->mt_flags |= MDB_TXN_ERROR;
return rc;
}
int
mdb_del(MDB_txn *txn, MDB_dbi dbi,
- MDB_val *key, MDB_val *data,
- unsigned int flags)
+ MDB_val *key, MDB_val *data)
{
+ MDB_cursor mc;
+ MDB_xcursor mx;
+ MDB_cursor_op op;
+ MDB_val rdata, *xdata;
int rc, exact;
- unsigned int ki;
- MDB_node *leaf;
- MDB_pageparent mpp;
-
- DPRINTF("========> delete key %.*s", (int)key->mv_size, (char *)key->mv_data);
+ DKBUF;
assert(key != NULL);
+ DPRINTF("====> delete db %u key [%s]", dbi, DKEY(key));
+
if (txn == NULL || !dbi || dbi >= txn->mt_numdbs)
return EINVAL;
if (F_ISSET(txn->mt_flags, MDB_TXN_RDONLY)) {
- return EINVAL;
+ return EACCES;
}
if (key->mv_size == 0 || key->mv_size > MAXKEYSIZE) {
return EINVAL;
}
- mpp.mp_parent = NULL;
- mpp.mp_pi = 0;
- if ((rc = mdb_search_page(txn, dbi, key, NULL, 1, &mpp)) != MDB_SUCCESS)
- return rc;
-
- leaf = mdb_search_node(txn, dbi, mpp.mp_page, key, &exact, &ki);
- if (leaf == NULL || !exact) {
- return MDB_NOTFOUND;
- }
-
- if (F_ISSET(txn->mt_dbs[dbi].md_flags, MDB_DUPSORT)) {
- MDB_xcursor mx;
- MDB_pageparent mp2;
-
- mdb_xcursor_init0(txn, dbi, &mx);
- mdb_xcursor_init1(txn, dbi, &mx, leaf);
- if (flags == MDB_DEL_DUP) {
- rc = mdb_del(&mx.mx_txn, mx.mx_cursor.mc_dbi, data, NULL, 0);
- mdb_xcursor_fini(txn, dbi, &mx);
- if (rc != MDB_SUCCESS)
- return rc;
- /* If sub-DB still has entries, we're done */
- if (mx.mx_txn.mt_dbs[mx.mx_cursor.mc_dbi].md_root != P_INVALID) {
- memcpy(NODEDATA(leaf), &mx.mx_txn.mt_dbs[mx.mx_cursor.mc_dbi],
- sizeof(MDB_db));
- return rc;
- }
- /* otherwise fall thru and delete the sub-DB */
- } else {
- /* add all the child DB's pages to the free list */
- rc = mdb_search_page(&mx.mx_txn, mx.mx_cursor.mc_dbi,
- NULL, &mx.mx_cursor, 0, &mp2);
- if (rc == MDB_SUCCESS) {
- MDB_ppage *top, *parent;
- MDB_node *ni;
- unsigned int i;
+ mdb_cursor_init(&mc, txn, dbi, &mx);
- cursor_pop_page(&mx.mx_cursor);
- top = CURSOR_TOP(&mx.mx_cursor);
- if (top != NULL) {
- parent = SLIST_NEXT(top, mp_entry);
- while (parent != NULL) {
- for (i=0; i<NUMKEYS(top->mp_page); i++) {
- ni = NODEPTR(top->mp_page, i);
- mdb_midl_insert(txn->mt_free_pgs, ni->mn_pgno);
- }
- if (parent) {
- parent->mp_ki++;
- if (parent->mp_ki >= NUMKEYS(parent->mp_page)) {
- cursor_pop_page(&mx.mx_cursor);
- top = CURSOR_TOP(&mx.mx_cursor);
- parent = SLIST_NEXT(top, mp_entry);
- } else {
- ni = NODEPTR(parent->mp_page, parent->mp_ki);
- top->mp_page = mdb_get_page(&mx.mx_txn, ni->mn_pgno);
- }
- }
- }
- }
- mdb_midl_insert(txn->mt_free_pgs, mx.mx_txn.mt_dbs[mx.mx_cursor.mc_dbi].md_root);
- }
- }
+ exact = 0;
+ if (data) {
+ op = MDB_GET_BOTH;
+ rdata = *data;
+ xdata = &rdata;
+ } else {
+ op = MDB_SET;
+ xdata = NULL;
}
-
- if (data && (rc = mdb_read_data(txn, leaf, data)) != MDB_SUCCESS)
- return rc;
-
- return mdb_del0(txn, dbi, ki, &mpp, leaf);
+ rc = mdb_cursor_set(&mc, key, xdata, op, &exact);
+ if (rc == 0)
+ rc = mdb_cursor_del(&mc, data ? 0 : MDB_NODUPDATA);
+ return rc;
}
-/* Split page <*mpp>, and insert <key,(data|newpgno)> in either left or
- * right sibling, at index <*newindxp> (as if unsplit). Updates *mpp and
- * *newindxp with the actual values after split, ie if *mpp and *newindxp
- * refer to a node in the new right sibling page.
+/** Split a page and insert a new node.
+ * @param[in,out] mc Cursor pointing to the page and desired insertion index.
+ * The cursor will be updated to point to the actual page and index where
+ * the node got inserted after the split.
+ * @param[in] newkey The key for the newly inserted node.
+ * @param[in] newdata The data for the newly inserted node.
+ * @param[in] newpgno The page number, if the new node is a branch node.
+ * @return 0 on success, non-zero on failure.
*/
static int
-mdb_split(MDB_txn *txn, MDB_dbi dbi, MDB_page **mpp, unsigned int *newindxp,
- MDB_val *newkey, MDB_val *newdata, pgno_t newpgno)
+mdb_page_split(MDB_cursor *mc, MDB_val *newkey, MDB_val *newdata, pgno_t newpgno,
+ unsigned int nflags)
{
- uint8_t flags;
- int rc = MDB_SUCCESS, ins_new = 0;
+ unsigned int flags;
+ int rc = MDB_SUCCESS, ins_new = 0, new_root = 0, newpos = 1;
indx_t newindx;
pgno_t pgno = 0;
- unsigned int i, j, split_indx;
+ unsigned int i, j, split_indx, nkeys, pmax;
MDB_node *node;
- MDB_val sepkey, rkey, rdata;
+ MDB_val sepkey, rkey, xdata, *rdata = &xdata;
MDB_page *copy;
- MDB_dpage *mdp, *rdp, *pdp;
- MDB_dhead *dh;
+ MDB_page *mp, *rp, *pp;
+ unsigned int ptop;
+ MDB_cursor mn;
+ DKBUF;
- assert(txn != NULL);
+ mp = mc->mc_pg[mc->mc_top];
+ newindx = mc->mc_ki[mc->mc_top];
- dh = ((MDB_dhead *)*mpp) - 1;
- mdp = (MDB_dpage *)dh;
- newindx = *newindxp;
+ DPRINTF("-----> splitting %s page %zu and adding [%s] at index %i",
+ IS_LEAF(mp) ? "leaf" : "branch", mp->mp_pgno,
+ DKEY(newkey), mc->mc_ki[mc->mc_top]);
- DPRINTF("-----> splitting %s page %lu and adding [%.*s] at index %i",
- IS_LEAF(&mdp->p) ? "leaf" : "branch", mdp->p.mp_pgno,
- (int)newkey->mv_size, (char *)newkey->mv_data, *newindxp);
+ /* Create a right sibling. */
+ if ((rp = mdb_page_new(mc, mp->mp_flags, 1)) == NULL)
+ return ENOMEM;
+ DPRINTF("new right sibling: page %zu", rp->mp_pgno);
- if (mdp->h.md_parent == NULL) {
- if ((pdp = mdb_new_page(txn, dbi, P_BRANCH, 1)) == NULL)
+ if (mc->mc_snum < 2) {
+ if ((pp = mdb_page_new(mc, P_BRANCH, 1)) == NULL)
return ENOMEM;
- mdp->h.md_pi = 0;
- mdp->h.md_parent = &pdp->p;
- txn->mt_dbs[dbi].md_root = pdp->p.mp_pgno;
- DPRINTF("root split! new root = %lu", pdp->p.mp_pgno);
- txn->mt_dbs[dbi].md_depth++;
+ /* shift current top to make room for new parent */
+ mc->mc_pg[1] = mc->mc_pg[0];
+ mc->mc_ki[1] = mc->mc_ki[0];
+ mc->mc_pg[0] = pp;
+ mc->mc_ki[0] = 0;
+ mc->mc_db->md_root = pp->mp_pgno;
+ DPRINTF("root split! new root = %zu", pp->mp_pgno);
+ mc->mc_db->md_depth++;
+ new_root = 1;
/* Add left (implicit) pointer. */
- if ((rc = mdb_add_node(txn, dbi, &pdp->p, 0, NULL, NULL,
- mdp->p.mp_pgno, 0)) != MDB_SUCCESS)
+ if ((rc = mdb_node_add(mc, 0, NULL, NULL, mp->mp_pgno, 0)) != MDB_SUCCESS) {
+ /* undo the pre-push */
+ mc->mc_pg[0] = mc->mc_pg[1];
+ mc->mc_ki[0] = mc->mc_ki[1];
+ mc->mc_db->md_root = mp->mp_pgno;
+ mc->mc_db->md_depth--;
return rc;
+ }
+ mc->mc_snum = 2;
+ mc->mc_top = 1;
+ ptop = 0;
} else {
- DPRINTF("parent branch page is %lu", mdp->h.md_parent->mp_pgno);
+ ptop = mc->mc_top-1;
+ DPRINTF("parent branch page is %zu", mc->mc_pg[ptop]->mp_pgno);
}
- /* Create a right sibling. */
- if ((rdp = mdb_new_page(txn, dbi, mdp->p.mp_flags, 1)) == NULL)
- return ENOMEM;
- rdp->h.md_parent = mdp->h.md_parent;
- rdp->h.md_pi = mdp->h.md_pi + 1;
- DPRINTF("new right sibling: page %lu", rdp->p.mp_pgno);
+ mdb_cursor_copy(mc, &mn);
+ mn.mc_pg[mn.mc_top] = rp;
+ mn.mc_ki[ptop] = mc->mc_ki[ptop]+1;
- /* Move half of the keys to the right sibling. */
- if ((copy = malloc(txn->mt_env->me_psize)) == NULL)
- return ENOMEM;
- memcpy(copy, &mdp->p, txn->mt_env->me_psize);
- memset(&mdp->p.mp_ptrs, 0, txn->mt_env->me_psize - PAGEHDRSZ);
- mdp->p.mp_lower = PAGEHDRSZ;
- mdp->p.mp_upper = txn->mt_env->me_psize;
+ if (nflags & MDB_APPEND) {
+ mn.mc_ki[mn.mc_top] = 0;
+ sepkey = *newkey;
+ nkeys = 0;
+ split_indx = 0;
+ goto newsep;
+ }
+
+ nkeys = NUMKEYS(mp);
+ split_indx = (nkeys + 1) / 2;
+
+ if (IS_LEAF2(rp)) {
+ char *split, *ins;
+ int x;
+ unsigned int lsize, rsize, ksize;
+ /* Move half of the keys to the right sibling */
+ copy = NULL;
+ x = mc->mc_ki[mc->mc_top] - split_indx;
+ ksize = mc->mc_db->md_pad;
+ split = LEAF2KEY(mp, split_indx, ksize);
+ rsize = (nkeys - split_indx) * ksize;
+ lsize = (nkeys - split_indx) * sizeof(indx_t);
+ mp->mp_lower -= lsize;
+ rp->mp_lower += lsize;
+ mp->mp_upper += rsize - lsize;
+ rp->mp_upper -= rsize - lsize;
+ sepkey.mv_size = ksize;
+ if (newindx == split_indx) {
+ sepkey.mv_data = newkey->mv_data;
+ } else {
+ sepkey.mv_data = split;
+ }
+ if (x<0) {
+ ins = LEAF2KEY(mp, mc->mc_ki[mc->mc_top], ksize);
+ memcpy(rp->mp_ptrs, split, rsize);
+ sepkey.mv_data = rp->mp_ptrs;
+ memmove(ins+ksize, ins, (split_indx - mc->mc_ki[mc->mc_top]) * ksize);
+ memcpy(ins, newkey->mv_data, ksize);
+ mp->mp_lower += sizeof(indx_t);
+ mp->mp_upper -= ksize - sizeof(indx_t);
+ } else {
+ if (x)
+ memcpy(rp->mp_ptrs, split, x * ksize);
+ ins = LEAF2KEY(rp, x, ksize);
+ memcpy(ins, newkey->mv_data, ksize);
+ memcpy(ins+ksize, split + x * ksize, rsize - x * ksize);
+ rp->mp_lower += sizeof(indx_t);
+ rp->mp_upper -= ksize - sizeof(indx_t);
+ mc->mc_ki[mc->mc_top] = x;
+ mc->mc_pg[mc->mc_top] = rp;
+ }
+ goto newsep;
+ }
- split_indx = NUMKEYS(copy) / 2 + 1;
+ /* For leaf pages, check the split point based on what
+ * fits where, since otherwise mdb_node_add can fail.
+ *
+ * This check is only needed when the data items are
+ * relatively large, such that being off by one will
+ * make the difference between success or failure.
+ * When the size of the data items is much smaller than
+ * one-half of a page, this check is irrelevant.
+ */
+ if (IS_LEAF(mp) && nkeys < 16) {
+ unsigned int psize, nsize;
+ /* Maximum free space in an empty page */
+ pmax = mc->mc_txn->mt_env->me_psize - PAGEHDRSZ;
+ nsize = mdb_leaf_size(mc->mc_txn->mt_env, newkey, newdata);
+ if (newindx <= split_indx) {
+ psize = nsize;
+ newpos = 0;
+ for (i=0; i<split_indx; i++) {
+ node = NODEPTR(mp, i);
+ psize += NODESIZE + NODEKSZ(node) + sizeof(indx_t);
+ if (F_ISSET(node->mn_flags, F_BIGDATA))
+ psize += sizeof(pgno_t);
+ else
+ psize += NODEDSZ(node);
+ psize += psize & 1;
+ if (psize > pmax) {
+ if (i == split_indx - 1 && newindx == split_indx)
+ newpos = 1;
+ else
+ split_indx = i;
+ break;
+ }
+ }
+ } else {
+ psize = nsize;
+ for (i=nkeys-1; i>=split_indx; i--) {
+ node = NODEPTR(mp, i);
+ psize += NODESIZE + NODEKSZ(node) + sizeof(indx_t);
+ if (F_ISSET(node->mn_flags, F_BIGDATA))
+ psize += sizeof(pgno_t);
+ else
+ psize += NODEDSZ(node);
+ psize += psize & 1;
+ if (psize > pmax) {
+ split_indx = i+1;
+ break;
+ }
+ }
+ }
+ }
/* First find the separating key between the split pages.
+ * The case where newindx == split_indx is ambiguous; the
+ * new item could go to the new page or stay on the original
+ * page. If newpos == 1 it goes to the new page.
*/
- memset(&sepkey, 0, sizeof(sepkey));
- if (newindx == split_indx) {
+ if (newindx == split_indx && newpos) {
sepkey.mv_size = newkey->mv_size;
sepkey.mv_data = newkey->mv_data;
} else {
- node = NODEPTR(copy, split_indx);
+ node = NODEPTR(mp, split_indx);
sepkey.mv_size = node->mn_ksize;
sepkey.mv_data = NODEKEY(node);
}
- DPRINTF("separator is [%.*s]", (int)sepkey.mv_size, (char *)sepkey.mv_data);
+newsep:
+ DPRINTF("separator is [%s]", DKEY(&sepkey));
/* Copy separator key to the parent.
*/
- if (SIZELEFT(rdp->h.md_parent) < mdb_branch_size(txn->mt_env, &sepkey)) {
- rc = mdb_split(txn, dbi, &rdp->h.md_parent, &rdp->h.md_pi,
- &sepkey, NULL, rdp->p.mp_pgno);
+ if (SIZELEFT(mn.mc_pg[ptop]) < mdb_branch_size(mc->mc_txn->mt_env, &sepkey)) {
+ mn.mc_snum--;
+ mn.mc_top--;
+ rc = mdb_page_split(&mn, &sepkey, NULL, rp->mp_pgno, 0);
/* Right page might now have changed parent.
* Check if left page also changed parent.
*/
- if (rdp->h.md_parent != mdp->h.md_parent &&
- mdp->h.md_pi >= NUMKEYS(mdp->h.md_parent)) {
- mdp->h.md_parent = rdp->h.md_parent;
- mdp->h.md_pi = rdp->h.md_pi - 1;
+ if (mn.mc_pg[ptop] != mc->mc_pg[ptop] &&
+ mc->mc_ki[ptop] >= NUMKEYS(mc->mc_pg[ptop])) {
+ mc->mc_pg[ptop] = mn.mc_pg[ptop];
+ mc->mc_ki[ptop] = mn.mc_ki[ptop] - 1;
}
} else {
- rc = mdb_add_node(txn, dbi, rdp->h.md_parent, rdp->h.md_pi,
- &sepkey, NULL, rdp->p.mp_pgno, 0);
+ mn.mc_top--;
+ rc = mdb_node_add(&mn, mn.mc_ki[ptop], &sepkey, NULL, rp->mp_pgno, 0);
+ mn.mc_top++;
}
if (rc != MDB_SUCCESS) {
- free(copy);
return rc;
}
+ if (nflags & MDB_APPEND) {
+ mc->mc_pg[mc->mc_top] = rp;
+ mc->mc_ki[mc->mc_top] = 0;
+ rc = mdb_node_add(mc, 0, newkey, newdata, newpgno, nflags);
+ if (rc)
+ return rc;
+ goto done;
+ }
+ if (IS_LEAF2(rp)) {
+ goto done;
+ }
- for (i = j = 0; i <= NUMKEYS(copy); j++) {
- if (i < split_indx) {
- /* Re-insert in left sibling. */
- pdp = mdp;
- } else {
- /* Insert in right sibling. */
- if (i == split_indx)
- /* Reset insert index for right sibling. */
- j = (i == newindx && ins_new);
- pdp = rdp;
+ /* Move half of the keys to the right sibling. */
+
+ /* grab a page to hold a temporary copy */
+ copy = mdb_page_malloc(mc);
+ if (copy == NULL)
+ return ENOMEM;
+
+ copy->mp_pgno = mp->mp_pgno;
+ copy->mp_flags = mp->mp_flags;
+ copy->mp_lower = PAGEHDRSZ;
+ copy->mp_upper = mc->mc_txn->mt_env->me_psize;
+ mc->mc_pg[mc->mc_top] = copy;
+ for (i = j = 0; i <= nkeys; j++) {
+ if (i == split_indx) {
+ /* Insert in right sibling. */
+ /* Reset insert index for right sibling. */
+ if (i != newindx || (newpos ^ ins_new)) {
+ j = 0;
+ mc->mc_pg[mc->mc_top] = rp;
+ }
}
if (i == newindx && !ins_new) {
/* Insert the original entry that caused the split. */
rkey.mv_data = newkey->mv_data;
rkey.mv_size = newkey->mv_size;
- if (IS_LEAF(&mdp->p)) {
- rdata.mv_data = newdata->mv_data;
- rdata.mv_size = newdata->mv_size;
+ if (IS_LEAF(mp)) {
+ rdata = newdata;
} else
pgno = newpgno;
- flags = 0;
+ flags = nflags;
ins_new = 1;
- /* Update page and index for the new key. */
- *newindxp = j;
- *mpp = &pdp->p;
- } else if (i == NUMKEYS(copy)) {
+ /* Update index for the new key. */
+ mc->mc_ki[mc->mc_top] = j;
+ } else if (i == nkeys) {
break;
} else {
- node = NODEPTR(copy, i);
+ node = NODEPTR(mp, i);
rkey.mv_data = NODEKEY(node);
rkey.mv_size = node->mn_ksize;
- if (IS_LEAF(&mdp->p)) {
- rdata.mv_data = NODEDATA(node);
- rdata.mv_size = node->mn_dsize;
+ if (IS_LEAF(mp)) {
+ xdata.mv_data = NODEDATA(node);
+ xdata.mv_size = NODEDSZ(node);
+ rdata = &xdata;
} else
- pgno = node->mn_pgno;
+ pgno = NODEPGNO(node);
flags = node->mn_flags;
i++;
}
- if (!IS_LEAF(&mdp->p) && j == 0) {
+ if (!IS_LEAF(mp) && j == 0) {
/* First branch index doesn't need key data. */
rkey.mv_size = 0;
}
- rc = mdb_add_node(txn, dbi, &pdp->p, j, &rkey, &rdata, pgno,flags);
+ rc = mdb_node_add(mc, j, &rkey, rdata, pgno, flags);
}
- free(copy);
- return rc;
-}
-
-static int
-mdb_put0(MDB_txn *txn, MDB_dbi dbi,
- MDB_val *key, MDB_val *data, unsigned int flags)
-{
- int rc = MDB_SUCCESS, exact;
- unsigned int ki;
- MDB_node *leaf;
- MDB_pageparent mpp;
- MDB_val xdata, *rdata;
- MDB_db dummy;
-
- DPRINTF("==> put key %.*s, size %zu, data size %zu",
- (int)key->mv_size, (char *)key->mv_data, key->mv_size, data->mv_size);
-
- mpp.mp_parent = NULL;
- mpp.mp_pi = 0;
- rc = mdb_search_page(txn, dbi, key, NULL, 1, &mpp);
- if (rc == MDB_SUCCESS) {
- leaf = mdb_search_node(txn, dbi, mpp.mp_page, key, &exact, &ki);
- if (leaf && exact) {
- if (F_ISSET(txn->mt_dbs[dbi].md_flags, MDB_DUPSORT)) {
- goto put_sub;
- }
- if (flags == MDB_NOOVERWRITE) {
- DPRINTF("duplicate key %.*s",
- (int)key->mv_size, (char *)key->mv_data);
- return MDB_KEYEXIST;
- }
- /* same size, just replace it */
- if (NODEDSZ(leaf) == data->mv_size) {
- memcpy(NODEDATA(leaf), data->mv_data, data->mv_size);
- goto done;
- }
- mdb_del_node(mpp.mp_page, ki);
- }
- if (leaf == NULL) { /* append if not found */
- ki = NUMKEYS(mpp.mp_page);
- DPRINTF("appending key at index %i", ki);
- }
- } else if (rc == MDB_NOTFOUND) {
- MDB_dpage *dp;
- /* new file, just write a root leaf page */
- DPRINTF("allocating new root leaf page");
- if ((dp = mdb_new_page(txn, dbi, P_LEAF, 1)) == NULL) {
- return ENOMEM;
+ nkeys = NUMKEYS(copy);
+ for (i=0; i<nkeys; i++)
+ mp->mp_ptrs[i] = copy->mp_ptrs[i];
+ mp->mp_lower = copy->mp_lower;
+ mp->mp_upper = copy->mp_upper;
+ memcpy(NODEPTR(mp, nkeys-1), NODEPTR(copy, nkeys-1),
+ mc->mc_txn->mt_env->me_psize - copy->mp_upper);
+
+ /* reset back to original page */
+ if (newindx < split_indx || (!newpos && newindx == split_indx)) {
+ mc->mc_pg[mc->mc_top] = mp;
+ if (nflags & MDB_RESERVE) {
+ node = NODEPTR(mp, mc->mc_ki[mc->mc_top]);
+ if (!(node->mn_flags & F_BIGDATA))
+ newdata->mv_data = NODEDATA(node);
}
- mpp.mp_page = &dp->p;
- txn->mt_dbs[dbi].md_root = mpp.mp_page->mp_pgno;
- txn->mt_dbs[dbi].md_depth++;
- ki = 0;
- }
- else
- goto done;
-
- assert(IS_LEAF(mpp.mp_page));
- DPRINTF("there are %u keys, should insert new key at index %i",
- NUMKEYS(mpp.mp_page), ki);
-
- /* For sorted dups, the data item at this level is a DB record
- * for a child DB; the actual data elements are stored as keys
- * in the child DB.
- */
- if (F_ISSET(txn->mt_dbs[dbi].md_flags, MDB_DUPSORT)) {
- rdata = &xdata;
- xdata.mv_size = sizeof(MDB_db);
- xdata.mv_data = &dummy;
- memset(&dummy, 0, sizeof(dummy));
- dummy.md_root = P_INVALID;
- } else {
- rdata = data;
- }
-
- if (SIZELEFT(mpp.mp_page) < mdb_leaf_size(txn->mt_env, key, rdata)) {
- rc = mdb_split(txn, dbi, &mpp.mp_page, &ki, key, rdata, P_INVALID);
- } else {
- /* There is room already in this leaf page. */
- rc = mdb_add_node(txn, dbi, mpp.mp_page, ki, key, rdata, 0, 0);
}
- if (rc != MDB_SUCCESS)
- txn->mt_flags |= MDB_TXN_ERROR;
- else {
- txn->mt_dbs[dbi].md_entries++;
-
- /* Remember if we just added a subdatabase */
- if (flags & F_SUBDATA) {
- leaf = NODEPTR(mpp.mp_page, ki);
- leaf->mn_flags |= F_SUBDATA;
- }
+ /* return tmp page to freelist */
+ copy->mp_next = mc->mc_txn->mt_env->me_dpages;
+ VGMEMP_FREE(mc->mc_txn->mt_env, copy);
+ mc->mc_txn->mt_env->me_dpages = copy;
+done:
+ {
+ /* Adjust other cursors pointing to mp */
+ MDB_cursor *m2, *m3;
+ MDB_dbi dbi = mc->mc_dbi;
- /* Now store the actual data in the child DB. Note that we're
- * storing the user data in the keys field, so there are strict
- * size limits on dupdata. The actual data fields of the child
- * DB are all zero size.
- */
- if (F_ISSET(txn->mt_dbs[dbi].md_flags, MDB_DUPSORT)) {
- MDB_xcursor mx;
+ if (mc->mc_flags & C_SUB)
+ dbi--;
- leaf = NODEPTR(mpp.mp_page, ki);
-put_sub:
- mdb_xcursor_init0(txn, dbi, &mx);
- mdb_xcursor_init1(txn, dbi, &mx, leaf);
- xdata.mv_size = 0;
- xdata.mv_data = "";
- if (flags == MDB_NODUPDATA)
- flags = MDB_NOOVERWRITE;
- rc = mdb_put0(&mx.mx_txn, mx.mx_cursor.mc_dbi, data, &xdata, flags);
- mdb_xcursor_fini(txn, dbi, &mx);
- memcpy(NODEDATA(leaf), &mx.mx_txn.mt_dbs[mx.mx_cursor.mc_dbi],
- sizeof(MDB_db));
+ for (m2 = mc->mc_txn->mt_cursors[dbi]; m2; m2=m2->mc_next) {
+ if (m2 == mc) continue;
+ if (mc->mc_flags & C_SUB)
+ m3 = &m2->mc_xcursor->mx_cursor;
+ else
+ m3 = m2;
+ if (!(m3->mc_flags & C_INITIALIZED))
+ continue;
+ if (new_root) {
+ int k;
+ /* root split */
+ for (k=m3->mc_top; k>=0; k--) {
+ m3->mc_ki[k+1] = m3->mc_ki[k];
+ m3->mc_pg[k+1] = m3->mc_pg[k];
+ }
+ m3->mc_ki[0] = mc->mc_ki[0];
+ m3->mc_pg[0] = mc->mc_pg[0];
+ m3->mc_snum++;
+ m3->mc_top++;
+ }
+ if (m3->mc_pg[mc->mc_top] == mp) {
+ if (m3->mc_ki[m3->mc_top] >= split_indx) {
+ m3->mc_pg[m3->mc_top] = rp;
+ m3->mc_ki[m3->mc_top] -= split_indx;
+ }
+ }
}
}
-
-done:
return rc;
}
mdb_put(MDB_txn *txn, MDB_dbi dbi,
MDB_val *key, MDB_val *data, unsigned int flags)
{
+ MDB_cursor mc;
+ MDB_xcursor mx;
+
assert(key != NULL);
assert(data != NULL);
return EINVAL;
if (F_ISSET(txn->mt_flags, MDB_TXN_RDONLY)) {
- return EINVAL;
+ return EACCES;
}
if (key->mv_size == 0 || key->mv_size > MAXKEYSIZE) {
return EINVAL;
}
- if ((flags & (MDB_NOOVERWRITE|MDB_NODUPDATA)) != flags)
+ if ((flags & (MDB_NOOVERWRITE|MDB_NODUPDATA|MDB_RESERVE|MDB_APPEND)) != flags)
return EINVAL;
- return mdb_put0(txn, dbi, key, data, flags);
+ mdb_cursor_init(&mc, txn, dbi, &mx);
+ return mdb_cursor_put(&mc, key, data, flags);
}
+/** Only a subset of the @ref mdb_env flags can be changed
+ * at runtime. Changing other flags requires closing the environment
+ * and re-opening it with the new flags.
+ */
+#define CHANGEABLE (MDB_NOSYNC)
int
mdb_env_set_flags(MDB_env *env, unsigned int flag, int onoff)
{
-#define CHANGEABLE (MDB_NOSYNC)
if ((flag & CHANGEABLE) != flag)
return EINVAL;
if (onoff)
return MDB_SUCCESS;
}
+/** Common code for #mdb_stat() and #mdb_env_stat().
+ * @param[in] env the environment to operate in.
+ * @param[in] db the #MDB_db record containing the stats to return.
+ * @param[out] arg the address of an #MDB_stat structure to receive the stats.
+ * @return 0, this function always succeeds.
+ */
static int
mdb_stat0(MDB_env *env, MDB_db *db, MDB_stat *arg)
{
int
mdb_env_stat(MDB_env *env, MDB_stat *arg)
{
+ int toggle;
+
if (env == NULL || arg == NULL)
return EINVAL;
- return mdb_stat0(env, &env->me_meta->mm_dbs[MAIN_DBI], arg);
+ mdb_env_read_meta(env, &toggle);
+
+ return mdb_stat0(env, &env->me_metas[toggle]->mm_dbs[MAIN_DBI], arg);
+}
+
+/** Set the default comparison functions for a database.
+ * Called immediately after a database is opened to set the defaults.
+ * The user can then override them with #mdb_set_compare() or
+ * #mdb_set_dupsort().
+ * @param[in] txn A transaction handle returned by #mdb_txn_begin()
+ * @param[in] dbi A database handle returned by #mdb_open()
+ */
+static void
+mdb_default_cmp(MDB_txn *txn, MDB_dbi dbi)
+{
+ if (txn->mt_dbs[dbi].md_flags & MDB_REVERSEKEY)
+ txn->mt_dbxs[dbi].md_cmp = mdb_cmp_memnr;
+ else if (txn->mt_dbs[dbi].md_flags & MDB_INTEGERKEY)
+ txn->mt_dbxs[dbi].md_cmp = mdb_cmp_cint;
+ else
+ txn->mt_dbxs[dbi].md_cmp = mdb_cmp_memn;
+
+ if (txn->mt_dbs[dbi].md_flags & MDB_DUPSORT) {
+ if (txn->mt_dbs[dbi].md_flags & MDB_INTEGERDUP) {
+ if (txn->mt_dbs[dbi].md_flags & MDB_DUPFIXED)
+ txn->mt_dbxs[dbi].md_dcmp = mdb_cmp_int;
+ else
+ txn->mt_dbxs[dbi].md_dcmp = mdb_cmp_cint;
+ } else if (txn->mt_dbs[dbi].md_flags & MDB_REVERSEDUP) {
+ txn->mt_dbxs[dbi].md_dcmp = mdb_cmp_memnr;
+ } else {
+ txn->mt_dbxs[dbi].md_dcmp = mdb_cmp_memn;
+ }
+ } else {
+ txn->mt_dbxs[dbi].md_dcmp = NULL;
+ }
}
int mdb_open(MDB_txn *txn, const char *name, unsigned int flags, MDB_dbi *dbi)
{
MDB_val key, data;
MDB_dbi i;
- int rc, dirty = 0;
+ MDB_cursor mc;
+ int rc, dbflag, exact;
size_t len;
+ if (txn->mt_dbxs[FREE_DBI].md_cmp == NULL) {
+ mdb_default_cmp(txn, FREE_DBI);
+ }
+
/* main DB? */
if (!name) {
*dbi = MAIN_DBI;
if (flags & (MDB_DUPSORT|MDB_REVERSEKEY|MDB_INTEGERKEY))
txn->mt_dbs[MAIN_DBI].md_flags |= (flags & (MDB_DUPSORT|MDB_REVERSEKEY|MDB_INTEGERKEY));
+ mdb_default_cmp(txn, MAIN_DBI);
return MDB_SUCCESS;
}
+ if (txn->mt_dbxs[MAIN_DBI].md_cmp == NULL) {
+ mdb_default_cmp(txn, MAIN_DBI);
+ }
+
/* Is the DB already open? */
len = strlen(name);
for (i=2; i<txn->mt_numdbs; i++) {
return ENFILE;
/* Find the DB info */
+ dbflag = 0;
+ exact = 0;
key.mv_size = len;
key.mv_data = (void *)name;
- rc = mdb_get(txn, MAIN_DBI, &key, &data);
-
- /* Create if requested */
- if (rc == MDB_NOTFOUND && (flags & MDB_CREATE)) {
+ mdb_cursor_init(&mc, txn, MAIN_DBI, NULL);
+ rc = mdb_cursor_set(&mc, &key, &data, MDB_SET, &exact);
+ if (rc == MDB_SUCCESS) {
+ /* make sure this is actually a DB */
+ MDB_node *node = NODEPTR(mc.mc_pg[mc.mc_top], mc.mc_ki[mc.mc_top]);
+ if (!(node->mn_flags & F_SUBDATA))
+ return EINVAL;
+ } else if (rc == MDB_NOTFOUND && (flags & MDB_CREATE)) {
+ /* Create if requested */
MDB_db dummy;
data.mv_size = sizeof(MDB_db);
data.mv_data = &dummy;
memset(&dummy, 0, sizeof(dummy));
dummy.md_root = P_INVALID;
dummy.md_flags = flags & 0xffff;
- rc = mdb_put0(txn, MAIN_DBI, &key, &data, F_SUBDATA);
- dirty = 1;
+ rc = mdb_cursor_put(&mc, &key, &data, F_SUBDATA);
+ dbflag = DB_DIRTY;
}
/* OK, got info, add to table */
if (rc == MDB_SUCCESS) {
txn->mt_dbxs[txn->mt_numdbs].md_name.mv_data = strdup(name);
txn->mt_dbxs[txn->mt_numdbs].md_name.mv_size = len;
- txn->mt_dbxs[txn->mt_numdbs].md_cmp = NULL;
- txn->mt_dbxs[txn->mt_numdbs].md_dcmp = NULL;
txn->mt_dbxs[txn->mt_numdbs].md_rel = NULL;
- txn->mt_dbxs[txn->mt_numdbs].md_parent = MAIN_DBI;
- txn->mt_dbxs[txn->mt_numdbs].md_dirty = dirty;
+ txn->mt_dbflags[txn->mt_numdbs] = dbflag;
memcpy(&txn->mt_dbs[txn->mt_numdbs], data.mv_data, sizeof(MDB_db));
*dbi = txn->mt_numdbs;
+ txn->mt_env->me_dbs[0][txn->mt_numdbs] = txn->mt_dbs[txn->mt_numdbs];
+ txn->mt_env->me_dbs[1][txn->mt_numdbs] = txn->mt_dbs[txn->mt_numdbs];
+ mdb_default_cmp(txn, txn->mt_numdbs);
txn->mt_numdbs++;
}
return mdb_stat0(txn->mt_env, &txn->mt_dbs[dbi], arg);
}
-void mdb_close(MDB_txn *txn, MDB_dbi dbi)
+void mdb_close(MDB_env *env, MDB_dbi dbi)
{
char *ptr;
- if (dbi <= MAIN_DBI || dbi >= txn->mt_numdbs)
+ if (dbi <= MAIN_DBI || dbi >= env->me_numdbs)
return;
- ptr = txn->mt_dbxs[dbi].md_name.mv_data;
- txn->mt_dbxs[dbi].md_name.mv_data = NULL;
- txn->mt_dbxs[dbi].md_name.mv_size = 0;
+ ptr = env->me_dbxs[dbi].md_name.mv_data;
+ env->me_dbxs[dbi].md_name.mv_data = NULL;
+ env->me_dbxs[dbi].md_name.mv_size = 0;
free(ptr);
}
+/** Add all the DB's pages to the free list.
+ * @param[in] mc Cursor on the DB to free.
+ * @param[in] subs non-Zero to check for sub-DBs in this DB.
+ * @return 0 on success, non-zero on failure.
+ */
+static int
+mdb_drop0(MDB_cursor *mc, int subs)
+{
+ int rc;
+
+ rc = mdb_page_search(mc, NULL, 0);
+ if (rc == MDB_SUCCESS) {
+ MDB_node *ni;
+ MDB_cursor mx;
+ unsigned int i;
+
+ /* LEAF2 pages have no nodes, cannot have sub-DBs */
+ if (!subs || IS_LEAF2(mc->mc_pg[mc->mc_top]))
+ mdb_cursor_pop(mc);
+
+ mdb_cursor_copy(mc, &mx);
+ while (mc->mc_snum > 0) {
+ if (IS_LEAF(mc->mc_pg[mc->mc_top])) {
+ for (i=0; i<NUMKEYS(mc->mc_pg[mc->mc_top]); i++) {
+ ni = NODEPTR(mc->mc_pg[mc->mc_top], i);
+ if (ni->mn_flags & F_SUBDATA) {
+ mdb_xcursor_init1(mc, ni);
+ rc = mdb_drop0(&mc->mc_xcursor->mx_cursor, 0);
+ if (rc)
+ return rc;
+ }
+ }
+ } else {
+ for (i=0; i<NUMKEYS(mc->mc_pg[mc->mc_top]); i++) {
+ pgno_t pg;
+ ni = NODEPTR(mc->mc_pg[mc->mc_top], i);
+ pg = NODEPGNO(ni);
+ /* free it */
+ mdb_midl_append(&mc->mc_txn->mt_free_pgs, pg);
+ }
+ }
+ if (!mc->mc_top)
+ break;
+ rc = mdb_cursor_sibling(mc, 1);
+ if (rc) {
+ /* no more siblings, go back to beginning
+ * of previous level. (stack was already popped
+ * by mdb_cursor_sibling)
+ */
+ for (i=1; i<mc->mc_top; i++)
+ mc->mc_pg[i] = mx.mc_pg[i];
+ }
+ }
+ /* free it */
+ mdb_midl_append(&mc->mc_txn->mt_free_pgs,
+ mc->mc_db->md_root);
+ }
+ return 0;
+}
+
+int mdb_drop(MDB_txn *txn, MDB_dbi dbi, int del)
+{
+ MDB_cursor *mc;
+ int rc;
+
+ if (!txn || !dbi || dbi >= txn->mt_numdbs)
+ return EINVAL;
+
+ if (F_ISSET(txn->mt_flags, MDB_TXN_RDONLY))
+ return EACCES;
+
+ rc = mdb_cursor_open(txn, dbi, &mc);
+ if (rc)
+ return rc;
+
+ rc = mdb_drop0(mc, mc->mc_db->md_flags & MDB_DUPSORT);
+ if (rc)
+ goto leave;
+
+ /* Can't delete the main DB */
+ if (del && dbi > MAIN_DBI) {
+ rc = mdb_del(txn, MAIN_DBI, &mc->mc_dbx->md_name, NULL);
+ if (!rc)
+ mdb_close(txn->mt_env, dbi);
+ } else {
+ txn->mt_dbflags[dbi] |= DB_DIRTY;
+ txn->mt_dbs[dbi].md_depth = 0;
+ txn->mt_dbs[dbi].md_branch_pages = 0;
+ txn->mt_dbs[dbi].md_leaf_pages = 0;
+ txn->mt_dbs[dbi].md_overflow_pages = 0;
+ txn->mt_dbs[dbi].md_entries = 0;
+ txn->mt_dbs[dbi].md_root = P_INVALID;
+ }
+leave:
+ mdb_cursor_close(mc);
+ return rc;
+}
+
int mdb_set_compare(MDB_txn *txn, MDB_dbi dbi, MDB_cmp_func *cmp)
{
if (txn == NULL || !dbi || dbi >= txn->mt_numdbs)
txn->mt_dbxs[dbi].md_rel = rel;
return MDB_SUCCESS;
}
+
+int mdb_set_relctx(MDB_txn *txn, MDB_dbi dbi, void *ctx)
+{
+ if (txn == NULL || !dbi || dbi >= txn->mt_numdbs)
+ return EINVAL;
+
+ txn->mt_dbxs[dbi].md_relctx = ctx;
+ return MDB_SUCCESS;
+}
+
+/** @} */
projects / openldap / blobdiff