#include <fcntl.h>
#ifdef _WIN32
+#include <windows.h>
#include <stdio.h>
#include <io.h>
-#include <sys/locking.h>
#endif
res = fcntl (fd, F_SETLKW, &lock_info);
#elif defined( _WIN32 )
- if( _lseek( fd, (ALOCK_SLOT_SIZE * slot), SEEK_SET ) < 0 )
- return -1;
- /*
- * _lock will try for the lock once per second, returning EDEADLOCK
- * after ten tries. We just loop until we either get the lock
- * or some other error is returned.
- */
- while((res = _locking( fd, _LK_LOCK, ALOCK_SLOT_SIZE )) < 0 ) {
- if( errno != EDEADLOCK )
- break;
- }
+ OVERLAPPED ov;
+ HANDLE hh = _get_osfhandle ( fd );
+ ov.hEvent = 0;
+ ov.Offset = ALOCK_SLOT_SIZE*slot;
+ ov.OffsetHigh = 0;
+ res = LockFileEx( hh, LOCKFILE_EXCLUSIVE_LOCK, 0,
+ ALOCK_SLOT_SIZE, 0, &ov ) ? 0 : -1;
#else
-# error alock needs lockf, fcntl, or _locking
+# error alock needs lockf, fcntl, or LockFile[Ex]
#endif
if (res == -1) {
assert (errno != EDEADLK);
res = fcntl (fd, F_SETLKW, &lock_info);
if (res == -1) return -1;
#elif defined( _WIN32 )
- res = _lseek (fd, (ALOCK_SLOT_SIZE * slot), SEEK_SET);
- if (res == -1) return -1;
- res = _locking( fd, _LK_UNLCK, ALOCK_SLOT_SIZE );
+ HANDLE hh = _get_osfhandle ( fd );
+ if ( !UnlockFile ( hh, ALOCK_SLOT_SIZE*slot, 0,
+ ALOCK_SLOT_SIZE, 0 ))
+ return -1;
+#else
+# error alock needs lockf, fcntl, or LockFile[Ex]
+#endif
+
+ return 0;
+}
+
+static int
+alock_share_lock ( int fd, int slot )
+{
+ int res;
+
+#if defined( HAVE_LOCKF )
+ res = 0; /* lockf has no shared locks */
+#elif defined ( HAVE_FCNTL )
+ struct flock lock_info;
+ (void) memset ((void *) &lock_info, 0, sizeof (struct flock));
+
+ /* The shared lock replaces the existing lock */
+ lock_info.l_type = F_RDLCK;
+ lock_info.l_whence = SEEK_SET;
+ lock_info.l_start = (off_t) (ALOCK_SLOT_SIZE * slot);
+ lock_info.l_len = (off_t) ALOCK_SLOT_SIZE;
+
+ res = fcntl (fd, F_SETLK, &lock_info);
if (res == -1) return -1;
+#elif defined( _WIN32 )
+ OVERLAPPED ov;
+ HANDLE hh = _get_osfhandle ( fd );
+
+ /* Windows locks are mandatory, not advisory.
+ * We must downgrade the lock to allow future
+ * callers to read the slot data.
+ *
+ * First acquire a shared lock. Unlock will
+ * release the existing exclusive lock.
+ */
+ ov.hEvent = 0;
+ ov.Offset = ALOCK_SLOT_SIZE*slot;
+ ov.OffsetHigh = 0;
+ LockFileEx (hh, 0, 0, ALOCK_SLOT_SIZE, 0, &ov);
+ UnlockFile (hh, ALOCK_SLOT_SIZE*slot, 0, ALOCK_SLOT_SIZE, 0);
#else
-# error alock needs lockf, fcntl, or _locking
+# error alock needs lockf, fcntl, or LockFile[Ex]
#endif
return 0;
if (lock_info.l_type != F_UNLCK) return ALOCK_LOCKED;
#elif defined( _WIN32 )
- res = _lseek (fd, (ALOCK_SLOT_SIZE * slot), SEEK_SET);
- if (res == -1) return -1;
- res = _locking( fd, _LK_NBLCK, ALOCK_SLOT_SIZE );
- _locking( fd, _LK_UNLCK, ALOCK_SLOT_SIZE );
- if (res == -1) {
- if( errno == EACCES ) {
- return ALOCK_LOCKED;
- } else {
- return -1;
- }
+ OVERLAPPED ov;
+ HANDLE hh = _get_osfhandle ( fd );
+ ov.hEvent = 0;
+ ov.Offset = ALOCK_SLOT_SIZE*slot;
+ ov.OffsetHigh = 0;
+ if( !LockFileEx( hh,
+ LOCKFILE_EXCLUSIVE_LOCK|LOCKFILE_FAIL_IMMEDIATELY, 0,
+ ALOCK_SLOT_SIZE, 0, &ov )) {
+ int err = GetLastError();
+ if ( err == ERROR_LOCK_VIOLATION )
+ return ALOCK_LOCKED;
+ else
+ return -1;
}
#else
-# error alock needs lockf, fcntl, or _locking
+# error alock needs lockf, fcntl, or LockFile
#endif
return 0;
}
ptr = lutil_strcopy(filename, envdir);
lutil_strcopy(ptr, "/alock");
+#ifdef _WIN32
+ { HANDLE handle = CreateFile (filename, GENERIC_READ|GENERIC_WRITE,
+ FILE_SHARE_READ|FILE_SHARE_WRITE, NULL, OPEN_ALWAYS,
+ FILE_ATTRIBUTE_NORMAL, NULL);
+ info->al_fd = _open_osfhandle (handle, 0);
+ }
+#else
info->al_fd = open (filename, O_CREAT|O_RDWR, 0666);
+#endif
ber_memfree (filename);
if (info->al_fd < 0) {
ber_memfree (slot_data.al_appname);
close (info->al_fd);
return ALOCK_UNSTABLE;
}
+ alock_share_lock (info->al_fd, info->al_slot);
res = alock_release_lock (info->al_fd, 0);
if (res == -1) {
res = alock_grab_lock (info->al_fd, 0);
if (res == -1) {
+fail:
+ /* Windows doesn't clean up locks immediately when a process exits.
+ * Make sure we release our locks, to prevent stale locks from
+ * hanging around.
+ */
+ alock_release_lock (info->al_fd, 0);
close (info->al_fd);
return ALOCK_UNSTABLE;
}
/* mark our slot as clean */
res = alock_read_slot (info, &slot_data);
if (res == -1) {
- close (info->al_fd);
if (slot_data.al_appname != NULL)
ber_memfree (slot_data.al_appname);
- return ALOCK_UNSTABLE;
+ goto fail;
}
slot_data.al_lock = ALOCK_UNLOCKED;
if ( nosave )
slot_data.al_lock |= ALOCK_NOSAVE;
+ /* since we have slot 0 locked, we don't need our slot lock */
+ res = alock_release_lock (info->al_fd, info->al_slot);
+ if (res == -1) {
+ goto fail;
+ }
res = alock_write_slot (info, &slot_data);
if (res == -1) {
- close (info->al_fd);
if (slot_data.al_appname != NULL)
ber_memfree (slot_data.al_appname);
- return ALOCK_UNSTABLE;
+ goto fail;
}
if (slot_data.al_appname != NULL) {
ber_memfree (slot_data.al_appname);
slot_data.al_appname = NULL;
}
- res = alock_release_lock (info->al_fd, info->al_slot);
- if (res == -1) {
- close (info->al_fd);
- return ALOCK_UNSTABLE;
- }
res = alock_release_lock (info->al_fd, 0);
if (res == -1) {
close (info->al_fd);
res = alock_grab_lock (info->al_fd, 0);
if (res == -1) {
- close (info->al_fd);
- return ALOCK_UNSTABLE;
+ goto fail;
}
res = fstat (info->al_fd, &statbuf);
if (res == -1) {
- close (info->al_fd);
- return ALOCK_UNSTABLE;
+ goto fail;
}
max_slot = (statbuf.st_size + ALOCK_SLOT_SIZE - 1) / ALOCK_SLOT_SIZE;
if (res == ALOCK_LOCKED
|| res == ALOCK_UNIQUE) {
/* recovery attempt on an active db? */
- close (info->al_fd);
- return ALOCK_UNSTABLE;
+ goto fail;
} else if (res == ALOCK_DIRTY) {
/* mark it clean */
res = alock_read_slot (&scan_info, &slot_data);
if (res == -1) {
- close (info->al_fd);
- return ALOCK_UNSTABLE;
+ goto fail;
}
slot_data.al_lock = ALOCK_UNLOCKED;
res = alock_write_slot (&scan_info, &slot_data);
if (res == -1) {
- close (info->al_fd);
if (slot_data.al_appname != NULL)
ber_memfree (slot_data.al_appname);
- return ALOCK_UNSTABLE;
+ goto fail;
}
if (slot_data.al_appname != NULL) {
ber_memfree (slot_data.al_appname);
}
} else if (res == -1) {
- close (info->al_fd);
- return ALOCK_UNSTABLE;
+ goto fail;
}
}
}
return ALOCK_CLEAN;
+
+fail:
+ alock_release_lock (info->al_fd, 0);
+ close (info->al_fd);
+ return ALOCK_UNSTABLE;
}
#endif /* SLAPD_BDB || SLAPD_HDB */
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