WORM: Write Once Read Many times xlator support

This xlator will allow files to be opened for write in append mode
only. Mount with --worm(glusterfs) or -o worm (mount) option to
enable worm xlator

Change-Id: I1be02fcf2aee2182ea2c66b514357918136fabeb
BUG: 3166
Reviewed-on: http://review.gluster.com/23
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Anand Avati <avati@gluster.com>

2 files changed, 22 insertions, 0 deletions

diff --git a/libglusterfs/src/glusterfs.h b/libglusterfs/src/glusterfs.h
index d4302028225..049bb8fc01f 100644
--- a/libglusterfs/src/glusterfs.h
+++ b/libglusterfs/src/glusterfs.h
@@ -276,6 +276,7 @@ struct _cmd_args {
 	int              debug_mode;
         int              read_only;
         int              acl;
+        int              worm;
         int              mac_compat;
 	struct list_head xlator_options;  /* list of xlator_option_t */
 
diff --git a/libglusterfs/src/graph.c b/libglusterfs/src/graph.c
index 725425d3994..acad239544b 100644
--- a/libglusterfs/src/graph.c
+++ b/libglusterfs/src/graph.c
@@ -247,6 +247,21 @@ glusterfs_graph_acl (glusterfs_graph_t *graph, glusterfs_ctx_t *ctx)
         return ret;
 }
 
+int
+glusterfs_graph_worm (glusterfs_graph_t *graph, glusterfs_ctx_t *ctx)
+{
+        int ret = 0;
+        cmd_args_t      *cmd_args = NULL;
+
+        cmd_args = &ctx->cmd_args;
+
+        if (!cmd_args->worm)
+                return 0;
+
+        ret = glusterfs_graph_insert (graph, ctx, "features/worm",
+                                      "worm-autoload");
+        return ret;
+}
 
 int
 glusterfs_graph_mac_compat (glusterfs_graph_t *graph, glusterfs_ctx_t *ctx)
@@ -475,6 +490,12 @@ glusterfs_graph_prepare (glusterfs_graph_t *graph, glusterfs_ctx_t *ctx)
                 return -1;
         }
 
+        /* XXX: WORM VOLUME */
+        ret = glusterfs_graph_worm (graph, ctx);
+        if (ret) {
+                gf_log ("graph", GF_LOG_ERROR, "glusterfs graph worm failed");
+                return -1;
+        }
         ret = glusterfs_graph_acl (graph, ctx);
         if (ret) {
                 gf_log ("graph", GF_LOG_ERROR, "glusterfs graph ACL failed");