s3: Implement global locks in a g_lock tdb

This is the basis to implement global locks in ctdb without depending on a
shared file system. The initial goal is to make ctdb persistent transactions
deterministic without too many timeouts.

2 files changed, 57 insertions, 0 deletions

diff --git a/source3/include/ctdbd_conn.h b/source3/include/ctdbd_conn.h
index d721235336..96e7aa08a6 100644
--- a/source3/include/ctdbd_conn.h
+++ b/source3/include/ctdbd_conn.h
@@ -73,5 +73,7 @@ NTSTATUS ctdbd_control_local(struct ctdbd_connection *conn, uint32 opcode,
 			     uint64_t srvid, uint32_t flags, TDB_DATA data, 
 			     TALLOC_CTX *mem_ctx, TDB_DATA *outdata,
 			     int *cstatus);
+NTSTATUS ctdb_watch_us(struct ctdbd_connection *conn);
+NTSTATUS ctdb_unwatch(struct ctdbd_connection *conn);
 
 #endif /* _CTDBD_CONN_H */
diff --git a/source3/include/g_lock.h b/source3/include/g_lock.h
new file mode 100644
index 0000000000..c0eed38d4b
--- /dev/null
+++ b/source3/include/g_lock.h
@@ -0,0 +1,55 @@
+/*
+   Unix SMB/CIFS implementation.
+   global locks based on ctdb
+   Copyright (C) 2009 by Volker Lendecke
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program 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 General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef _G_LOCK_H_
+#define _G_LOCK_H_
+
+#include "dbwrap.h"
+
+struct g_lock_ctx;
+
+enum g_lock_type {
+	G_LOCK_READ = 0,
+	G_LOCK_WRITE = 1,
+};
+
+/*
+ * Or'ed with g_lock_type
+ */
+#define G_LOCK_PENDING (2)
+
+struct g_lock_ctx *g_lock_ctx_init(TALLOC_CTX *mem_ctx,
+				   struct messaging_context *msg);
+
+NTSTATUS g_lock_lock(struct g_lock_ctx *ctx, const char *name,
+		     enum g_lock_type lock_type, struct timeval timeout);
+NTSTATUS g_lock_unlock(struct g_lock_ctx *ctx, const char *name);
+NTSTATUS g_lock_get(struct g_lock_ctx *ctx, const char *name,
+		struct server_id *pid);
+
+int g_lock_locks(struct g_lock_ctx *ctx,
+		 int (*fn)(const char *name, void *private_data),
+		 void *private_data);
+NTSTATUS g_lock_dump(struct g_lock_ctx *ctx, const char *name,
+		     int (*fn)(struct server_id pid,
+			       enum g_lock_type lock_type,
+			       void *private_data),
+		     void *private_data);
+
+#endif