Merge remote branch 'origin/mdb.master'

diff --git a/libraries/libmdb/mdb.c b/libraries/libmdb/mdb.c
index 8a877c744f6f90ffc7864a77f0cab46c5e0cfc13..a6df703c37948060379d1fa291d6f88ff52472cc 100644 (file)
--- a/libraries/libmdb/mdb.c
+++ b/libraries/libmdb/mdb.c
@@ -691,9 +691,6 @@ typedef struct MDB_meta {
        /** Auxiliary DB info.
         *      The information here is mostly static/read-only. There is
         *      only a single copy of this record in the environment.
-        *      The \b md_dirty flag is not read-only, but only a write
-        *      transaction can ever update it, and only write transactions
-        *      need to worry about it.
         */
 typedef struct MDB_dbx {
        MDB_val         md_name;                /**< name of the database */
@@ -701,8 +698,6 @@ typedef struct MDB_dbx {
        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_dbi md_parent;                      /**< parent DB of a sub-DB */
-       unsigned int    md_dirty;       /**< TRUE if DB was written in this txn */
 } MDB_dbx;
 
        /** A database transaction.
@@ -717,9 +712,8 @@ struct MDB_txn {
        txnid_t         mt_txnid;
        MDB_env         *mt_env;                /**< the DB environment */
        /** The list of pages that became unused during this transaction.
-        *      This is an #IDL.
         */
-       pgno_t          *mt_free_pgs;
+       IDL                     mt_free_pgs;
        union {
                ID2L    dirty_list;     /**< modified pages */
                MDB_reader      *reader;        /**< this thread's slot in the reader table */
@@ -728,6 +722,15 @@ struct MDB_txn {
        MDB_dbx         *mt_dbxs;
        /** Array of MDB_db records for each known DB */
        MDB_db          *mt_dbs;
+/** @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 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.
         */
@@ -767,6 +770,8 @@ struct MDB_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, mc_snum-1 */
 /** @defgroup mdb_cursor       Cursor Flags
@@ -794,6 +799,8 @@ typedef struct MDB_xcursor {
        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. */
@@ -830,13 +837,14 @@ struct MDB_env {
        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 */
        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 */
-       pgno_t          me_free_pgs[MDB_IDL_UM_SIZE];
+       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 */
@@ -899,6 +907,7 @@ static void mdb_cursor_init(MDB_cursor *mc, MDB_txn *txn, MDB_dbi dbi, MDB_xcurs
 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 */
@@ -1126,7 +1135,7 @@ mdb_page_touch(MDB_cursor *mc)
                        return ENOMEM;
                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);
+               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;
@@ -1167,6 +1176,7 @@ static inline int
 mdb_txn_renew0(MDB_txn *txn)
 {
        MDB_env *env = txn->mt_env;
+       char mt_dbflag = 0;
 
        if (txn->mt_flags & MDB_TXN_RDONLY) {
                MDB_reader *r = pthread_getspecific(env->me_txkey);
@@ -1191,14 +1201,22 @@ mdb_txn_renew0(MDB_txn *txn)
                        r = &env->me_txns->mti_readers[i];
                        pthread_setspecific(env->me_txkey, r);
                }
-               txn->mt_txnid = env->me_txns->mti_txnid;
                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 {
                LOCK_MUTEX_W(env);
 
-               txn->mt_txnid = env->me_txns->mti_txnid+1;
+               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;
@@ -1218,6 +1236,8 @@ mdb_txn_renew0(MDB_txn *txn)
                        (txn->mt_numdbs - 2) * sizeof(MDB_db));
        LAZY_RWLOCK_UNLOCK(&env->me_dblock);
 
+       memset(txn->mt_dbflags, mt_dbflag, env->me_numdbs);
+
        return MDB_SUCCESS;
 }
 
@@ -1253,7 +1273,8 @@ mdb_txn_begin(MDB_env *env, unsigned int flags, MDB_txn **ret)
                DPUTS("environment had fatal error, must shutdown!");
                return MDB_PANIC;
        }
-       if ((txn = calloc(1, sizeof(MDB_txn) + env->me_maxdbs * sizeof(MDB_db))) == NULL) {
+       if ((txn = calloc(1, sizeof(MDB_txn) +
+               env->me_maxdbs * (sizeof(MDB_db)+1))) == NULL) {
                DPRINTF("calloc: %s", strerror(ErrCode()));
                return ENOMEM;
        }
@@ -1261,6 +1282,7 @@ mdb_txn_begin(MDB_env *env, unsigned int flags, MDB_txn **ret)
        if (flags & MDB_RDONLY) {
                txn->mt_flags |= MDB_TXN_RDONLY;
        }
+       txn->mt_dbflags = (unsigned char *)(txn->mt_dbs + env->me_maxdbs);
        txn->mt_env = env;
 
        rc = mdb_txn_renew0(txn);
@@ -1289,9 +1311,11 @@ mdb_txn_reset0(MDB_txn *txn)
        } else {
                MDB_oldpages *mop;
                MDB_page *dp;
-               MDB_dbi dbi;
                unsigned int i;
 
+               if (mdb_midl_shrink(&txn->mt_free_pgs))
+                       env->me_free_pgs = txn->mt_free_pgs;
+
                /* 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;
@@ -1310,8 +1334,6 @@ mdb_txn_reset0(MDB_txn *txn)
                }
 
                env->me_txn = NULL;
-               for (dbi=2; dbi<env->me_numdbs; dbi++)
-                       env->me_dbxs[dbi].md_dirty = 0;
                /* The writer mutex was locked in mdb_txn_begin. */
                UNLOCK_MUTEX_W(env);
        }
@@ -1362,6 +1384,23 @@ mdb_txn_commit(MDB_txn *txn)
        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;
        }
@@ -1430,6 +1469,8 @@ mdb_txn_commit(MDB_txn *txn)
                                return rc;
                        }
                } while (i != txn->mt_free_pgs[0]);
+               if (mdb_midl_shrink(&txn->mt_free_pgs))
+                       env->me_free_pgs = txn->mt_free_pgs;
        }
        /* should only be one record now */
        if (env->me_pghead) {
@@ -1456,7 +1497,7 @@ mdb_txn_commit(MDB_txn *txn)
 
                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_cursor_put(&mc, &txn->mt_dbxs[i].md_name, &data, 0);
                        }
@@ -1578,6 +1619,7 @@ mdb_txn_commit(MDB_txn *txn)
        }
 
 done:
+       env->me_wtxnid = txn->mt_txnid;
        env->me_txn = NULL;
        /* update the DB tables */
        {
@@ -1594,10 +1636,6 @@ done:
                        ip++; jp++;
                }
 
-               for (i = 2; i < txn->mt_numdbs; i++) {
-                       if (txn->mt_dbxs[i].md_dirty)
-                               txn->mt_dbxs[i].md_dirty = 0;
-               }
                env->me_db_toggle = toggle;
                env->me_numdbs = txn->mt_numdbs;
                LAZY_RWLOCK_UNLOCK(&env->me_dblock);
@@ -1834,6 +1872,11 @@ mdb_env_create(MDB_env **env)
        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 = INVALID_HANDLE_VALUE;
@@ -2457,6 +2500,7 @@ mdb_env_close(MDB_env *env)
                munmap(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);
 }
 
@@ -2825,16 +2869,32 @@ mdb_page_search(MDB_cursor *mc, MDB_val *key, int modify)
        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 (mc->mc_dbi > MAIN_DBI && !mc->mc_dbx->md_dirty) {
+       /* For sub-databases, update main root first */
+       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, 1);
+                       rc = mdb_page_search(&mc2, &mc->mc_dbx->md_name, modify);
                        if (rc)
                                return rc;
-                       mc->mc_dbx->md_dirty = 1;
+                       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;
                }
+       }
+       if (modify) {
                if (!F_ISSET(mc->mc_pg[0]->mp_flags, P_DIRTY)) {
                        if ((rc = mdb_page_touch(mc)))
                                return rc;
@@ -3475,13 +3535,13 @@ mdb_cursor_touch(MDB_cursor *mc)
 {
        int rc;
 
-       if (mc->mc_dbi > MAIN_DBI && !mc->mc_dbx->md_dirty) {
+       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_dbx->md_dirty = 1;
+               *mc->mc_dbflag = DB_DIRTY;
        }
        for (mc->mc_top = 0; mc->mc_top < mc->mc_snum; mc->mc_top++) {
                if (!F_ISSET(mc->mc_pg[mc->mc_top]->mp_flags, P_DIRTY)) {
@@ -3502,7 +3562,7 @@ int
 mdb_cursor_put(MDB_cursor *mc, MDB_val *key, MDB_val *data,
     unsigned int flags)
 {
-       MDB_node        *leaf;
+       MDB_node        *leaf = NULL;
        MDB_val xdata, *rdata, dkey;
        MDB_page        *fp;
        MDB_db dummy;
@@ -3536,7 +3596,7 @@ mdb_cursor_put(MDB_cursor *mc, MDB_val *key, MDB_val *data,
                mdb_cursor_push(mc, np);
                mc->mc_db->md_root = np->mp_pgno;
                mc->mc_db->md_depth++;
-               mc->mc_dbx->md_dirty = 1;
+               *mc->mc_dbflag = DB_DIRTY;
                if ((mc->mc_db->md_flags & (MDB_DUPSORT|MDB_DUPFIXED))
                        == MDB_DUPFIXED)
                        np->mp_flags |= P_LEAF2;
@@ -3799,45 +3859,10 @@ mdb_cursor_del(MDB_cursor *mc, unsigned int flags)
 
                if (leaf->mn_flags & F_SUBDATA) {
                        /* add all the child DB's pages to the free list */
-                       rc = mdb_page_search(&mc->mc_xcursor->mx_cursor, NULL, 0);
+                       rc = mdb_drop0(&mc->mc_xcursor->mx_cursor, 0);
                        if (rc == MDB_SUCCESS) {
-                               MDB_node *ni;
-                               MDB_cursor *mx;
-                               unsigned int i;
-
-                               mx = &mc->mc_xcursor->mx_cursor;
                                mc->mc_db->md_entries -=
-                                       mx->mc_db->md_entries;
-
-                               mdb_cursor_pop(mx);
-                               while (mx->mc_snum > 0) {
-                                       for (i=0; i<NUMKEYS(mx->mc_pg[mx->mc_top]); i++) {
-                                               pgno_t pg;
-                                               ni = NODEPTR(mx->mc_pg[mx->mc_top], i);
-                                               pg = NODEPGNO(ni);
-                                               /* free it */
-                                               mdb_midl_append(mc->mc_txn->mt_free_pgs, pg);
-                                       }
-                                       if (!mx->mc_top)
-                                               break;
-                                       rc = mdb_cursor_sibling(mx, 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<mx->mc_top; i++) {
-                                                       pgno_t pg;
-                                                       ni = NODEPTR(mx->mc_pg[i-1],0);
-                                                       pg = NODEPGNO(ni);
-                                                       if ((rc = mdb_page_get(mc->mc_txn, pg, &mx->mc_pg[i])))
-                                                               break;
-                                               }
-                                       }
-                               }
-                               /* free it */
-                               mdb_midl_append(mc->mc_txn->mt_free_pgs,
-                                       mx->mc_db->md_root);
+                                       mc->mc_xcursor->mx_db.md_entries;
                        }
                }
        }
@@ -4181,11 +4206,10 @@ mdb_xcursor_init0(MDB_cursor *mc)
        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_dbx.md_parent = mc->mc_dbi;
+       mx->mx_cursor.mc_dbflag = &mx->mx_dbflag;
        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;
-       mx->mx_dbx.md_dirty = 0;
 }
 
 /** Final setup of a sorted-dups cursor.
@@ -4228,8 +4252,8 @@ mdb_xcursor_init1(MDB_cursor *mc, MDB_node *node)
        }
        DPRINTF("Sub-db %u for db %u root page %zu", mx->mx_cursor.mc_dbi, mc->mc_dbi,
                mx->mx_db.md_root);
-       if (F_ISSET(mc->mc_pg[mc->mc_top]->mp_flags, P_DIRTY))
-               mx->mx_dbx.md_dirty = 1;
+       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 (mx->mx_dbx.md_cmp == mdb_cmp_int && mx->mx_db.md_pad == sizeof(size_t))
@@ -4244,6 +4268,7 @@ mdb_cursor_init(MDB_cursor *mc, MDB_txn *txn, MDB_dbi dbi, MDB_xcursor *mx)
        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_flags = 0;
        if (txn->mt_dbs[dbi].md_flags & MDB_DUPSORT) {
@@ -4535,7 +4560,7 @@ mdb_page_merge(MDB_cursor *csrc, MDB_cursor *cdst)
                        return rc;
        }
 
-       mdb_midl_append(csrc->mc_txn->mt_free_pgs, csrc->mc_pg[csrc->mc_top]->mp_pgno);
+       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
@@ -4597,11 +4622,11 @@ mdb_rebalance(MDB_cursor *mc)
                        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, mc->mc_pg[mc->mc_top]->mp_pgno);
+                       mdb_midl_append(&mc->mc_txn->mt_free_pgs, mc->mc_pg[mc->mc_top]->mp_pgno);
                        mc->mc_snum = 0;
                } else if (IS_BRANCH(mc->mc_pg[mc->mc_top]) && NUMKEYS(mc->mc_pg[mc->mc_top]) == 1) {
                        DPUTS("collapsing root page!");
-                       mdb_midl_append(mc->mc_txn->mt_free_pgs, mc->mc_pg[mc->mc_top]->mp_pgno);
+                       mdb_midl_append(&mc->mc_txn->mt_free_pgs, mc->mc_pg[mc->mc_top]->mp_pgno);
                        mc->mc_db->md_root = NODEPGNO(NODEPTR(mc->mc_pg[mc->mc_top], 0));
                        if ((rc = mdb_page_get(mc->mc_txn, mc->mc_db->md_root,
                                &mc->mc_pg[mc->mc_top])))
@@ -4685,7 +4710,7 @@ mdb_cursor_del0(MDB_cursor *mc, MDB_node *leaf)
                ovpages = OVPAGES(NODEDSZ(leaf), mc->mc_txn->mt_env->me_psize);
                for (i=0; i<ovpages; i++) {
                        DPRINTF("freed ov page %zu", pg);
-                       mdb_midl_append(mc->mc_txn->mt_free_pgs, pg);
+                       mdb_midl_append(&mc->mc_txn->mt_free_pgs, pg);
                        pg++;
                }
        }
@@ -5152,7 +5177,7 @@ 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;
+       int rc, dbflag = 0;
        size_t len;
 
        if (txn->mt_dbxs[FREE_DBI].md_cmp == NULL) {
@@ -5201,7 +5226,7 @@ int mdb_open(MDB_txn *txn, const char *name, unsigned int flags, MDB_dbi *dbi)
                dummy.md_flags = flags & 0xffff;
                mdb_cursor_init(&mc, txn, MAIN_DBI, NULL);
                rc = mdb_cursor_put(&mc, &key, &data, F_SUBDATA);
-               dirty = 1;
+               dbflag = DB_DIRTY;
        }
 
        /* OK, got info, add to table */
@@ -5209,8 +5234,7 @@ int mdb_open(MDB_txn *txn, const char *name, unsigned int flags, MDB_dbi *dbi)
                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_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];
@@ -5230,17 +5254,103 @@ int mdb_stat(MDB_txn *txn, MDB_dbi dbi, MDB_stat *arg)
        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;
+
+       rc = mdb_cursor_open(txn, dbi, &mc);
+       if (rc)
+               return rc;
+
+       rc = mdb_drop0(mc, 1);
+       if (rc)
+               mdb_cursor_close(mc);
+               return rc;
+
+       if (del) {
+               rc = mdb_del(txn, MAIN_DBI, &mc->mc_dbx->md_name, NULL);
+               if (!rc)
+                       mdb_close(txn->mt_env, dbi);
+       }
+       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)

diff --git a/libraries/libmdb/mdb.h b/libraries/libmdb/mdb.h
index b99ece7c95b0cda81ded04b42bb8e465c4c52588..18d73681eab5259b384254456ac7665b460ee9d0 100644 (file)
--- a/libraries/libmdb/mdb.h
+++ b/libraries/libmdb/mdb.h
@@ -531,7 +531,9 @@ void mdb_txn_reset(MDB_txn *txn);
 int  mdb_txn_renew(MDB_txn *txn);
 
        /** Open a database in the environment.
-        * The database handle may be discarded by calling #mdb_close().
+        * The database handle may be discarded by calling #mdb_close(). Only
+        * one thread should call this function; it is not mutex-protected in
+        * a read-only transaction.
         * @param[in] txn A transaction handle returned by #mdb_txn_begin()
         * @param[in] name The name of the database to open. If only a single
         *      database is needed in the enviroment, this value may be NULL.
@@ -592,15 +594,29 @@ int  mdb_open(MDB_txn *txn, const char *name, unsigned int flags, MDB_dbi *dbi);
 int  mdb_stat(MDB_txn *txn, MDB_dbi dbi, MDB_stat *stat);
 
        /** Close a database handle.
+        * This call is not mutex protected. Handles should only be closed by
+        * a single thread, and only if no other threads are going to reference
+        * the database handle any further.
+        * @param[in] env An environment handle returned by #mdb_env_create()
+        * @param[in] dbi A database handle returned by #mdb_open()
+        */
+void mdb_close(MDB_env *env, MDB_dbi dbi);
+
+       /** Delete a database and/or free all its pages.
+        * If the \b del parameter is non-zero the DB handle will be closed
+        * and the DB will be deleted.
         * @param[in] txn A transaction handle returned by #mdb_txn_begin()
         * @param[in] dbi A database handle returned by #mdb_open()
+        * @param[in] del non-zero to delete the DB from the environment,
+        * otherwise just free its pages.
+        * @return A non-zero error value on failure and 0 on success.
         */
-void mdb_close(MDB_txn *txn, MDB_dbi dbi);
+int  mdb_drop(MDB_txn *txn, MDB_dbi dbi, int del);
 
        /** Set a custom key comparison function for a database.
         * The comparison function is called whenever it is necessary to compare a
         * key specified by the application with a key currently stored in the database.
-        * If no comparison function is specified, and no special key flags were specified
+        * If no comparison function is specified, and no speAGAINcial key flags were specified
         * with #mdb_open(), the keys are compared lexically, with shorter keys collating
         * before longer keys.
         * @warning This function must be called before any data access functions are used,

diff --git a/libraries/libmdb/mdb_stat.c b/libraries/libmdb/mdb_stat.c
index 4bcdb92fa62cb98fac4797f6ef24b07e555bf751..931ec61a581e11f3549ca35c94404df5652fe8c2 100644 (file)
--- a/libraries/libmdb/mdb_stat.c
+++ b/libraries/libmdb/mdb_stat.c
@@ -56,7 +56,7 @@ int main(int argc,char * argv[])
        printf("Leaf pages: %zu\n", mst.ms_leaf_pages);
        printf("Overflow pages: %zu\n", mst.ms_overflow_pages);
        printf("Entries: %zu\n", mst.ms_entries);
-       mdb_close(txn, dbi);
+       mdb_close(env, dbi);
        mdb_txn_abort(txn);
        mdb_env_close(env);
 

diff --git a/libraries/libmdb/midl.c b/libraries/libmdb/midl.c
index 7a7b59c7c0e053cb752defb001c2a3e253fd1ea2..70487aa3d95118975365ed74cf3c2ae02a901091 100644 (file)
--- a/libraries/libmdb/midl.c
+++ b/libraries/libmdb/midl.c
@@ -17,6 +17,7 @@
 
 #include <limits.h>
 #include <string.h>
+#include <stdlib.h>
 #include <sys/types.h>
 #include <assert.h>
 #include "midl.h"
@@ -117,11 +118,44 @@ int mdb_midl_insert( IDL ids, ID id )
 }
 #endif
 
-int mdb_midl_append( IDL ids, ID id )
+IDL mdb_midl_alloc()
 {
+       IDL ids = malloc((MDB_IDL_UM_MAX+1) * sizeof(ID));
+       *ids++ = MDB_IDL_UM_MAX;
+       return ids;
+}
+
+void mdb_midl_free(IDL ids)
+{
+       free(ids-1);
+}
+
+int mdb_midl_shrink( IDL *idp )
+{
+       IDL ids = *idp;
+       if (ids[-1] > MDB_IDL_UM_MAX) {
+               ids = realloc(ids, (MDB_IDL_UM_MAX+1) * sizeof(ID));
+               *ids++ = MDB_IDL_UM_MAX;
+               *idp = ids;
+               return 1;
+       }
+       return 0;
+}
+
+int mdb_midl_append( IDL *idp, ID id )
+{
+       IDL ids = *idp;
        /* Too big? */
-       if (ids[0] >= MDB_IDL_UM_MAX)
-               return -1;
+       if (ids[0] >= ids[-1]) {
+               IDL idn = ids-1;
+               /* grow it */
+               idn = realloc(idn, (*idn + MDB_IDL_UM_MAX + 1) * sizeof(ID));
+               if (!idn)
+                       return -1;
+               *idn++ += MDB_IDL_UM_MAX;
+               ids = idn;
+               *idp = ids;
+       }
        ids[0]++;
        ids[ids[0]] = id;
        return 0;

diff --git a/libraries/libmdb/midl.h b/libraries/libmdb/midl.h
index 041aa03b3a9d55d5f16ce57f59f1e12f5ebfadfa..0ab89e03330dca958b494732d7346496e9ab2bc0 100644 (file)
--- a/libraries/libmdb/midl.h
+++ b/libraries/libmdb/midl.h
@@ -111,12 +111,30 @@ typedef ID *IDL;
 int mdb_midl_insert( IDL ids, ID id );
 #endif
 
+       /** Allocate an IDL.
+        * Allocates memory for an IDL of a default size.
+        * @return      IDL on success, NULL on failure.
+        */
+IDL mdb_midl_alloc();
+
+       /** Free an IDL.
+        * @param[in] ids       The IDL to free.
+        */
+void mdb_midl_free(IDL ids);
+
+       /** Shrink an IDL.
+        * Return the IDL to the default size if it has grown larger.
+        * @param[in,out] idp   Address of the IDL to shrink.
+        * @return      0 on no change, non-zero if shrunk.
+        */
+int mdb_midl_shrink(IDL *idp);
+
        /** Append an ID onto an IDL.
-        * @param[in,out] ids   The IDL to append to.
+        * @param[in,out] idp   Address of the IDL to append to.
         * @param[in] id        The ID to append.
         * @return      0 on success, -2 if the IDL is too large.
         */
-int mdb_midl_append( IDL ids, ID id );
+int mdb_midl_append( IDL *idp, ID id );
 
        /** Sort an IDL.
         * @param[in,out] ids   The IDL to sort.

diff --git a/libraries/libmdb/mtest.c b/libraries/libmdb/mtest.c
index 8f2ecbf0e906ecb2f5951d72e2ef65997766ae19..89f0ac46433216e5a35d9426dc30ff3dfebdda8f 100644 (file)
--- a/libraries/libmdb/mtest.c
+++ b/libraries/libmdb/mtest.c
@@ -146,7 +146,7 @@ int main(int argc,char * argv[])
                }
 #endif
                mdb_cursor_close(cursor);
-               mdb_close(txn, dbi);
+               mdb_close(env, dbi);
 
                mdb_txn_abort(txn);
                mdb_env_close(env);

diff --git a/libraries/libmdb/mtest2.c b/libraries/libmdb/mtest2.c
index 5aeb97d3d42f7375c85db26f2c3ef5205ba37edc..17c1ecfe59a13c92b32e29bda21c282214a6fe36 100644 (file)
--- a/libraries/libmdb/mtest2.c
+++ b/libraries/libmdb/mtest2.c
@@ -108,7 +108,7 @@ int main(int argc,char * argv[])
                        (int) data.mv_size, (char *) data.mv_data);
        }
        mdb_cursor_close(cursor);
-       mdb_close(txn, dbi);
+       mdb_close(env, dbi);
 
        mdb_txn_abort(txn);
        mdb_env_close(env);

diff --git a/libraries/libmdb/mtest3.c b/libraries/libmdb/mtest3.c
index 467a12352ddc6e90d9b6f283797441abe877e0c3..43e34817b94474ba8b47995416e6297a80cfd5e4 100644 (file)
--- a/libraries/libmdb/mtest3.c
+++ b/libraries/libmdb/mtest3.c
@@ -118,7 +118,7 @@ int main(int argc,char * argv[])
                        (int) data.mv_size, (char *) data.mv_data);
        }
        mdb_cursor_close(cursor);
-       mdb_close(txn, dbi);
+       mdb_close(env, dbi);
 
        mdb_txn_abort(txn);
        mdb_env_close(env);

diff --git a/libraries/libmdb/mtest4.c b/libraries/libmdb/mtest4.c
index d3a7877417f39833a35bb761991b99e305a616e1..821055ad7c13c4930fb53a6c99bac8ca865a9d0c 100644 (file)
--- a/libraries/libmdb/mtest4.c
+++ b/libraries/libmdb/mtest4.c
@@ -152,7 +152,7 @@ int main(int argc,char * argv[])
                        (int) data.mv_size, (char *) data.mv_data);
        }
        mdb_cursor_close(cursor);
-       mdb_close(txn, dbi);
+       mdb_close(env, dbi);
 
        mdb_txn_abort(txn);
        mdb_env_close(env);

diff --git a/libraries/libmdb/mtest5.c b/libraries/libmdb/mtest5.c
index 472b100756f7476b49e498189a595c48b89aff9b..5fb6bb061883b9603f5a5bcd51ffd7f5317986a7 100644 (file)
--- a/libraries/libmdb/mtest5.c
+++ b/libraries/libmdb/mtest5.c
@@ -120,7 +120,7 @@ int main(int argc,char * argv[])
                        (int) data.mv_size, (char *) data.mv_data);
        }
        mdb_cursor_close(cursor);
-       mdb_close(txn, dbi);
+       mdb_close(env, dbi);
 
        mdb_txn_abort(txn);
        mdb_env_close(env);