Changeset 745 for trunk/server/lib/tdb/common/open.c

Timestamp:

Nov 27, 2012, 4:43:17 PM (13 years ago)

Author:

Silvan Scherrer

Message:

Samba Server: updated trunk to 3.6.0

Location:

trunk/server

Files:

• . (modified) (1 prop)
• lib/tdb/common/open.c (modified) (34 diffs)

trunk/server/lib/tdb/common/open.c

@@ -7 +7 @@
    Copyright (C) Paul `Rusty' Russell              2000
    Copyright (C) Jeremy Allison                    2000-2003
-   
+
      ** NOTE! The following LGPL license applies to the tdb
      ** library. This does NOT imply that all of Samba is released
      ** under the LGPL
-   
+
    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
@@ -36 +36 @@
 static struct tdb_context *tdbs = NULL;
 
-
-/* This is based on the hash algorithm from gdbm */
-static unsigned int default_tdb_hash(TDB_DATA *key)
-{
-        uint32_t value; /* Used to compute the hash value.  */
-        uint32_t   i;   /* Used to cycle through random values. */
-
-        /* Set the initial value from the key size. */
-        for (value = 0x238F13AF * key->dsize, i=0; i < key->dsize; i++)
-                value = (value + (key->dptr[i] << (i*5 % 24)));
-
-        return (1103515243 * value + 12345);  
-}
-
+/* We use two hashes to double-check they're using the right hash function. */
+void tdb_header_hash(struct tdb_context *tdb,
+                     uint32_t *magic1_hash, uint32_t *magic2_hash)
+{
+        TDB_DATA hash_key;
+        uint32_t tdb_magic = TDB_MAGIC;
+
+        hash_key.dptr = discard_const_p(unsigned char, TDB_MAGIC_FOOD);
+        hash_key.dsize = sizeof(TDB_MAGIC_FOOD);
+        *magic1_hash = tdb->hash_fn(&hash_key);
+
+        hash_key.dptr = (unsigned char *)CONVERT(tdb_magic);
+        hash_key.dsize = sizeof(tdb_magic);
+        *magic2_hash = tdb->hash_fn(&hash_key);
+
+        /* Make sure at least one hash is non-zero! */
+        if (*magic1_hash == 0 && *magic2_hash == 0)
+                *magic1_hash = 1;
+}
 
 /* initialise a new database with a specified hash size */
@@ -57 +62 @@
         size_t size;
         int ret = -1;
-        ssize_t written;
 
         /* We make it up in memory, then write it out if not internal */
@@ -69 +73 @@
         newdb->version = TDB_VERSION;
         newdb->hash_size = hash_size;
+
+        tdb_header_hash(tdb, &newdb->magic1_hash, &newdb->magic2_hash);
+
+        /* Make sure older tdbs (which don't check the magic hash fields)
+         * will refuse to open this TDB. */
+        if (tdb->flags & TDB_INCOMPATIBLE_HASH)
+                newdb->rwlocks = TDB_HASH_RWLOCK_MAGIC;
+
         if (tdb->flags & TDB_INTERNAL) {
                 tdb->map_size = size;
@@ -89 +101 @@
         memcpy(newdb->magic_food, TDB_MAGIC_FOOD, strlen(TDB_MAGIC_FOOD)+1);
         /* we still have "ret == -1" here */
-        written = write(tdb->fd, newdb, size);
-        if (written == size) {
+        if (tdb_write_all(tdb->fd, newdb, size))
                 ret = 0;
-        } else if (written != -1) {
-                /* call write once again, this usually should return -1 and
-                 * set errno appropriately */
-                size -= written;
-                written = write(tdb->fd, newdb+written, size);
-                if (written == size) {
-                ret = 0;
-                } else if (written >= 0) {
-                        /* a second incomplete write - we give up.
-                         * guessing the errno... */
-                        errno = ENOSPC;
-                }
-        }
 
   fail:
@@ -117 +115 @@
 {
         struct tdb_context *i;
-        
+
         for (i = tdbs; i; i = i->next) {
                 if (i->device == device && i->inode == ino) {
@@ -137 +135 @@
 
    @param name may be NULL for internal databases. */
-struct tdb_context *tdb_open(const char *name, int hash_size, int tdb_flags,
+_PUBLIC_ struct tdb_context *tdb_open(const char *name, int hash_size, int tdb_flags,
                       int open_flags, mode_t mode)
 {
@@ -149 +147 @@
 }
 
-
-struct tdb_context *tdb_open_ex(const char *name, int hash_size, int tdb_flags,
+static bool check_header_hash(struct tdb_context *tdb,
+                              bool default_hash, uint32_t *m1, uint32_t *m2)
+{
+        tdb_header_hash(tdb, m1, m2);
+        if (tdb->header.magic1_hash == *m1 &&
+            tdb->header.magic2_hash == *m2) {
+                return true;
+        }
+
+        /* If they explicitly set a hash, always respect it. */
+        if (!default_hash)
+                return false;
+
+        /* Otherwise, try the other inbuilt hash. */
+        if (tdb->hash_fn == tdb_old_hash)
+                tdb->hash_fn = tdb_jenkins_hash;
+        else
+                tdb->hash_fn = tdb_old_hash;
+        return check_header_hash(tdb, false, m1, m2);
+}
+
+_PUBLIC_ struct tdb_context *tdb_open_ex(const char *name, int hash_size, int tdb_flags,
                                 int open_flags, mode_t mode,
                                 const struct tdb_logging_context *log_ctx,
@@ -161 +179 @@
         uint32_t vertest;
         unsigned v;
+        const char *hash_alg;
+        uint32_t magic1, magic2;
 
         if (!(tdb = (struct tdb_context *)calloc(1, sizeof *tdb))) {
@@ -182 +202 @@
                 tdb->log.log_private = NULL;
         }
-        tdb->hash_fn = hash_fn ? hash_fn : default_tdb_hash;
+
+        if (name == NULL && (tdb_flags & TDB_INTERNAL)) {
+                name = "__TDB_INTERNAL__";
+        }
+
+        if (name == NULL) {
+                tdb->name = discard_const_p(char, "__NULL__");
+                TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_open_ex: called with name == NULL\n"));
+                tdb->name = NULL;
+                errno = EINVAL;
+                goto fail;
+        }
+
+        /* now make a copy of the name, as the caller memory might went away */
+        if (!(tdb->name = (char *)strdup(name))) {
+                /*
+                 * set the name as the given string, so that tdb_name() will
+                 * work in case of an error.
+                 */
+                tdb->name = discard_const_p(char, name);
+                TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_open_ex: can't strdup(%s)\n",
+                         name));
+                tdb->name = NULL;
+                errno = ENOMEM;
+                goto fail;
+        }
+
+        if (hash_fn) {
+                tdb->hash_fn = hash_fn;
+                hash_alg = "the user defined";
+        } else {
+                /* This controls what we use when creating a tdb. */
+                if (tdb->flags & TDB_INCOMPATIBLE_HASH) {
+                        tdb->hash_fn = tdb_jenkins_hash;
+                } else {
+                        tdb->hash_fn = tdb_old_hash;
+                }
+                hash_alg = "either default";
+        }
 
 #ifdef __OS2__
@@ -189 +247 @@
         }
 #endif
-
         /* cache the page size */
         tdb->page_size = getpagesize();
@@ -204 +261 @@
                 goto fail;
         }
-        
+
         if (hash_size == 0)
                 hash_size = DEFAULT_HASH_SIZE;
@@ -223 +280 @@
         }
 
+        if (getenv("TDB_NO_FSYNC")) {
+                tdb->flags |= TDB_NOSYNC;
+        }
+
         /*
          * TDB_ALLOW_NESTING is the default behavior.
@@ -253 +314 @@
 
         /* ensure there is only one process initialising at once */
-        if (tdb->methods->tdb_brlock(tdb, GLOBAL_LOCK, F_WRLCK, F_SETLKW, 0, 1) == -1) {
-                TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_open_ex: failed to get global lock on %s: %s\n",
+        if (tdb_nest_lock(tdb, OPEN_LOCK, F_WRLCK, TDB_LOCK_WAIT) == -1) {
+                TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_open_ex: failed to get open lock on %s: %s\n",
                          name, strerror(errno)));
                 goto fail;      /* errno set by tdb_brlock */
@@ -261 +322 @@
         /* we need to zero database if we are the only one with it open */
         if ((tdb_flags & TDB_CLEAR_IF_FIRST) &&
-            (!tdb->read_only)
 #ifndef __OS2__
-            && (locked = (tdb->methods->tdb_brlock(tdb, ACTIVE_LOCK, F_WRLCK, F_SETLK, 0, 1) == 0))
-#endif
-            ) {
+            (!tdb->read_only) &&
+            (locked = (tdb_nest_lock(tdb, ACTIVE_LOCK, F_WRLCK, TDB_LOCK_NOWAIT|TDB_LOCK_PROBE) == 0))) {
+#else
+            (!tdb->read_only) ) {
+#endif
                 open_flags |= O_CREAT;
                 if (ftruncate(tdb->fd, 0) == -1) {
@@ -304 +366 @@
                 goto fail;
 
-        if (tdb->header.rwlocks != 0) {
+        if (tdb->header.rwlocks != 0 &&
+            tdb->header.rwlocks != TDB_HASH_RWLOCK_MAGIC) {
                 TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_open_ex: spinlocks no longer supported\n"));
+                goto fail;
+        }
+
+        if ((tdb->header.magic1_hash == 0) && (tdb->header.magic2_hash == 0)) {
+                /* older TDB without magic hash references */
+                tdb->hash_fn = tdb_old_hash;
+        } else if (!check_header_hash(tdb, !hash_fn, &magic1, &magic2)) {
+                TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_open_ex: "
+                         "%s was not created with %s hash function we are using\n"
+                         "magic1_hash[0x%08X %s 0x%08X] "
+                         "magic2_hash[0x%08X %s 0x%08X]\n",
+                         name, hash_alg,
+                         tdb->header.magic1_hash,
+                         (tdb->header.magic1_hash == magic1) ? "==" : "!=",
+                         magic1,
+                         tdb->header.magic2_hash,
+                         (tdb->header.magic2_hash == magic2) ? "==" : "!=",
+                         magic2));
+                errno = EINVAL;
                 goto fail;
         }
@@ -318 +400 @@
         }
 
-        if (!(tdb->name = (char *)strdup(name))) {
-                errno = ENOMEM;
-                goto fail;
-        }
-
         tdb->map_size = st.st_size;
         tdb->device = st.st_dev;
@@ -329 +406 @@
         if (locked) {
 #ifndef __OS2__
-                if (tdb->methods->tdb_brlock(tdb, ACTIVE_LOCK, F_UNLCK, F_SETLK, 0, 1) == -1) {
+                if (tdb_nest_unlock(tdb, ACTIVE_LOCK, F_WRLCK, false) == -1) {
                         TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_open_ex: "
-                                 "failed to take ACTIVE_LOCK on %s: %s\n",
+                                 "failed to release ACTIVE_LOCK on %s: %s\n",
                                  name, strerror(errno)));
                         goto fail;
                 }
-
 #endif
         }
@@ -346 +422 @@
         if (tdb_flags & TDB_CLEAR_IF_FIRST) {
                 /* leave this lock in place to indicate it's in use */
-                if (tdb->methods->tdb_brlock(tdb, ACTIVE_LOCK, F_RDLCK, F_SETLKW, 0, 1) == -1)
+                if (tdb_nest_lock(tdb, ACTIVE_LOCK, F_RDLCK, TDB_LOCK_WAIT) == -1) {
                         goto fail;
+                }
         }
 #endif
@@ -358 +435 @@
 #ifdef __OS2__
         // YD internal databases do not get global lock!
-        if (tdb->methods->tdb_brlock(tdb, GLOBAL_LOCK, F_UNLCK, F_SETLKW, 0, 1) == -1)
+        if (tdb_nest_unlock(tdb, OPEN_LOCK, F_WRLCK, false) == -1)
                 goto fail;
 #endif
@@ -381 +458 @@
         /* Internal (memory-only) databases skip all the code above to
          * do with disk files, and resume here by releasing their
-         * global lock and hooking into the active list. */
+         * open lock and hooking into the active list. */
 #ifndef __OS2__
-        if (tdb->methods->tdb_brlock(tdb, GLOBAL_LOCK, F_UNLCK, F_SETLKW, 0, 1) == -1)
-                goto fail;
+        if (tdb_nest_unlock(tdb, OPEN_LOCK, F_WRLCK, false) == -1) {
+                goto fail;
+        }
 #endif
         tdb->next = tdbs;
-                tdbs = tdb;
+        tdbs = tdb;
         return tdb;
 
@@ -405 +483 @@
                         tdb_munmap(tdb);
         }
-        SAFE_FREE(tdb->name);
+        if (tdb->fd != -1)
+                if (close(tdb->fd) != 0)
+                        TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_open_ex: failed to close tdb->fd on error!\n"));
 #ifdef __OS2__
         DosCloseMutexSem( tdb->hGlobalLock);
@@ -414 +494 @@
         tdb->hTransactionLock = 0;
 #endif
-        if (tdb->fd != -1)
-                if (close(tdb->fd) != 0)
-                        TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_open_ex: failed to close tdb->fd on error!\n"));
+        SAFE_FREE(tdb->lockrecs);
+        SAFE_FREE(tdb->name);
         SAFE_FREE(tdb);
         errno = save_errno;
@@ -427 +506 @@
  */
 
-void tdb_set_max_dead(struct tdb_context *tdb, int max_dead)
+_PUBLIC_ void tdb_set_max_dead(struct tdb_context *tdb, int max_dead)
 {
         tdb->max_dead_records = max_dead;
@@ -437 +516 @@
  * @returns -1 for error; 0 for success.
  **/
-int tdb_close(struct tdb_context *tdb)
+_PUBLIC_ int tdb_close(struct tdb_context *tdb)
 {
         struct tdb_context **i;
         int ret = 0;
 
+        if (tdb->transaction) {
+                tdb_transaction_cancel(tdb);
+        }
         tdb_trace(tdb, "tdb_close");
-        if (tdb->transaction) {
-                _tdb_transaction_cancel(tdb);
-        }
 
         if (tdb->map_ptr) {
@@ -457 +536 @@
         // YD internal databases do not have a global lock
         if (!(tdb->flags & TDB_INTERNAL))
-                tdb->methods->tdb_brlock(tdb, GLOBAL_LOCK, F_UNLCK, F_SETLK, 0, 1);
+        tdb_nest_unlock(tdb, OPEN_LOCK, F_WRLCK, false);
 #endif
         if (tdb->fd != -1) {
@@ -491 +570 @@
 
 /* register a loging function */
-void tdb_set_logging_function(struct tdb_context *tdb,
-                              const struct tdb_logging_context *log_ctx)
+_PUBLIC_ void tdb_set_logging_function(struct tdb_context *tdb,
+                                       const struct tdb_logging_context *log_ctx)
 {
         tdb->log = *log_ctx;
 }
 
-void *tdb_get_logging_private(struct tdb_context *tdb)
+_PUBLIC_ void *tdb_get_logging_private(struct tdb_context *tdb)
 {
         return tdb->log.log_private;
@@ -526 +605 @@
 #endif
 
-        if (tdb->num_locks != 0 || tdb->global_lock.count) {
+        if (tdb_have_extra_locks(tdb)) {
                 TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_reopen: reopen not allowed with locks held\n"));
                 goto fail;
@@ -561 +640 @@
 #endif /* fake pread or pwrite */
 
-        if (active_lock &&
-            (tdb->methods->tdb_brlock(tdb, ACTIVE_LOCK, F_RDLCK, F_SETLKW, 0, 1) == -1)) {
+        /* We may still think we hold the active lock. */
+        tdb->num_lockrecs = 0;
+        SAFE_FREE(tdb->lockrecs);
+
+        if (active_lock && tdb_nest_lock(tdb, ACTIVE_LOCK, F_RDLCK, TDB_LOCK_WAIT) == -1) {
                 TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_reopen: failed to obtain active lock\n"));
                 goto fail;
@@ -576 +658 @@
 /* reopen a tdb - this can be used after a fork to ensure that we have an independent
    seek pointer from our parent and to re-establish locks */
-int tdb_reopen(struct tdb_context *tdb)
+_PUBLIC_ int tdb_reopen(struct tdb_context *tdb)
 {
         return tdb_reopen_internal(tdb, tdb->flags & TDB_CLEAR_IF_FIRST);
@@ -582 +664 @@
 
 /* reopen all tdb's */
-int tdb_reopen_all(int parent_longlived)
+_PUBLIC_ int tdb_reopen_all(int parent_longlived)
 {
         struct tdb_context *tdb;
@@ -623 +705 @@
                 // extract path info
                 _splitpath( name, drive, dir, fname, ext);
-                sprintf( szSem, "\\SEM32\\TDB_GL_%s%s%s%i", dir, fname, ext, global_Sem32Add);
+                sprintf( szSem, "\\SEM32\\TDB_OL_%s%s%s%i", dir, fname, ext, global_Sem32Add);
                 rc = DosCreateMutexSem( szSem, &tdb->hGlobalLock, 0, FALSE);
                 if (rc == ERROR_DUPLICATE_NAME)
@@ -632 +714 @@
                         return -1;
                 }
-                TDB_LOG((tdb, TDB_DEBUG_TRACE,"%s pid %d global handle %d\n", caller, getpid(), tdb->hGlobalLock));
+                TDB_LOG((tdb, TDB_DEBUG_TRACE,"%s pid %d open handle %d\n", caller, getpid(), tdb->hGlobalLock));
 
                 sprintf( szSem, "\\SEM32\\TDB_AL_%s%s%s%i", dir, fname, ext, global_Sem32Add);
@@ -659 +741 @@
 }
 #endif
-