1 files changed, 115 insertions, 0 deletions
diff --git a/source4/lib/ldb/ldb_tdb/ldb_tdb_wrap.c b/source4/lib/ldb/ldb_tdb/ldb_tdb_wrap.c
new file mode 100644
index 0000000000..f58ec7f7ff
--- /dev/null
+++ b/source4/lib/ldb/ldb_tdb/ldb_tdb_wrap.c
@@ -0,0 +1,115 @@
+/* 
+   ldb database library
+
+   Copyright (C) Andrew Tridgell  2005
+
+     ** NOTE! The following LGPL license applies to the ldb
+     ** 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
+   License as published by the Free Software Foundation; either
+   version 2 of the License, or (at your option) any later version.
+
+   This library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with this library; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+*/
+
+#include "includes.h"
+#include "ldb/include/ldb.h"
+#include "ldb/include/ldb_private.h"
+#include "ldb/ldb_tdb/ldb_tdb.h"
+
+/*
+  the purpose of this code is to work around the braindead posix locking
+  rules, to allow us to have a ldb open more than once while allowing 
+  locking to work
+*/
+
+struct ltdb_wrap {
+	struct ltdb_wrap *next, *prev;
+	struct tdb_context *tdb;
+	dev_t device;
+	ino_t inode;
+};
+
+static struct ltdb_wrap *tdb_list;
+
+/* destroy the last connection to a tdb */
+static int ltdb_wrap_destructor(void *ctx)
+{
+	struct ltdb_wrap *w = talloc_get_type(ctx, struct ltdb_wrap);
+	tdb_close(w->tdb);
+	if (w->next) {
+		w->next->prev = w->prev;
+	}
+	if (w->prev) {
+		w->prev->next = w->next;
+	}
+	if (w == tdb_list) {
+		tdb_list = w->next;
+	}
+	return 0;
+}				 
+
+/*
+  wrapped connection to a tdb database. The caller should _not_ free
+  this as it is not a talloc structure (as tdb does not use talloc
+  yet). It will auto-close when the caller frees the mem_ctx that is
+  passed to this call
+ */
+struct tdb_context *ltdb_wrap_open(TALLOC_CTX *mem_ctx,
+				   const char *path, int hash_size, int tdb_flags,
+				   int open_flags, mode_t mode)
+{
+	struct ltdb_wrap *w;
+	struct stat st;
+
+	if (stat(path, &st) == 0) {
+		for (w=tdb_list;w;w=w->next) {
+			if (st.st_dev == w->device && st.st_ino == w->inode) {
+				talloc_reference(mem_ctx, w);
+				return w->tdb;
+			}
+		}
+	}
+
+	w = talloc(mem_ctx, struct ltdb_wrap);
+	if (w == NULL) {
+		return NULL;
+	}
+
+	w->tdb = tdb_open(path, hash_size, tdb_flags, open_flags, mode);
+	if (w->tdb == NULL) {
+		talloc_free(w);
+		return NULL;
+	}
+
+	if (fstat(w->tdb->fd, &st) != 0) {
+		tdb_close(w->tdb);
+		talloc_free(w);
+		return NULL;
+	}
+
+	w->device = st.st_dev;
+	w->inode  = st.st_ino;
+
+	talloc_set_destructor(w, ltdb_wrap_destructor);
+
+	w->next = tdb_list;
+	w->prev = NULL;
+	if (tdb_list) {
+		tdb_list->prev = w;
+	}
+	tdb_list = w;
+	
+	return w->tdb;
+}
+