s3:g_lock: add callback function to g_lock_lock_simple_fn()

BUG: https://bugzilla.samba.org/show_bug.cgi?id=15125

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>

diff --git a/source3/lib/g_lock.c b/source3/lib/g_lock.c
index 7e27f2ea52a998db3b0019f00598e45f71bb0378..7868a69a3371a3c5984dda0012991056b5bea30a 100644 (file)
--- a/source3/lib/g_lock.c
+++ b/source3/lib/g_lock.c
@@ -1127,9 +1127,12 @@ NTSTATUS g_lock_lock_recv(struct tevent_req *req)
 }
 
 struct g_lock_lock_simple_state {
+       struct g_lock_ctx *ctx;
        struct server_id me;
        enum g_lock_type type;
        NTSTATUS status;
+       g_lock_lock_cb_fn_t cb_fn;
+       void *cb_private;
 };
 
 static void g_lock_lock_simple_fn(
@@ -1140,7 +1143,15 @@ static void g_lock_lock_simple_fn(
        struct g_lock_lock_simple_state *state = private_data;
        struct server_id_buf buf;
        struct g_lock lck = { .exclusive.pid = 0 };
-       struct server_id *new_shared = NULL;
+       struct g_lock_lock_cb_state cb_state = {
+               .ctx = state->ctx,
+               .rec = rec,
+               .lck = &lck,
+               .cb_fn = state->cb_fn,
+               .cb_private = state->cb_private,
+               .existed = value.dsize != 0,
+               .update_mem_ctx = talloc_tos(),
+       };
        bool ok;
 
        ok = g_lock_parse(value.dptr, value.dsize, &lck);
@@ -1164,7 +1175,7 @@ static void g_lock_lock_simple_fn(
                lck.exclusive = state->me;
        } else if (state->type == G_LOCK_READ) {
                g_lock_cleanup_shared(&lck);
-               new_shared = &state->me;
+               cb_state.new_shared = &state->me;
        } else {
                smb_panic(__location__);
        }
@@ -1172,15 +1183,23 @@ static void g_lock_lock_simple_fn(
        lck.unique_lock_epoch = generate_unique_u64(lck.unique_lock_epoch);
 
        /*
-        * We're storing a lock and if we are
-        * successful in doing that, we should not
-        * wakeup any other waiters, all they would
-        * find is that we're holding a lock they
-        * are conflicting with.
+        * We are going to store us as owner,
+        * so we got what we were waiting for.
+        *
+        * So we no longer need to monitor the
+        * record.
         */
        dbwrap_watched_watch_skip_alerting(rec);
 
-       state->status = g_lock_store(rec, &lck, new_shared, NULL, 0);
+       state->status = g_lock_lock_cb_run_and_store(&cb_state);
+       if (!NT_STATUS_IS_OK(state->status) &&
+           !NT_STATUS_EQUAL(state->status, NT_STATUS_WAS_UNLOCKED))
+       {
+               DBG_WARNING("g_lock_lock_cb_run_and_store() failed: %s\n",
+                           nt_errstr(state->status));
+               return;
+       }
+
        return;
 
 not_granted:
@@ -1190,6 +1209,8 @@ not_granted:
 NTSTATUS g_lock_lock(struct g_lock_ctx *ctx, TDB_DATA key,
                     enum g_lock_type type, struct timeval timeout)
 {
+       g_lock_lock_cb_fn_t cb_fn = NULL;
+       void *cb_private = NULL;
        TALLOC_CTX *frame;
        struct tevent_context *ev;
        struct tevent_req *req;
@@ -1209,8 +1230,11 @@ NTSTATUS g_lock_lock(struct g_lock_ctx *ctx, TDB_DATA key,
                 * improvement for lock/unlock.
                 */
                struct g_lock_lock_simple_state state = {
+                       .ctx = ctx,
                        .me = messaging_server_id(ctx->msg),
                        .type = type,
+                       .cb_fn = cb_fn,
+                       .cb_private = cb_private,
                };
                status = dbwrap_do_locked(
                        ctx->db, key, g_lock_lock_simple_fn, &state);
@@ -1231,6 +1255,10 @@ NTSTATUS g_lock_lock(struct g_lock_ctx *ctx, TDB_DATA key,
                        }
                        return NT_STATUS_OK;
                }
+               if (NT_STATUS_EQUAL(state.status, NT_STATUS_WAS_UNLOCKED)) {
+                       /* without dbwrap_lock_order_lock() */
+                       return NT_STATUS_OK;
+               }
                if (!NT_STATUS_EQUAL(
                            state.status, NT_STATUS_LOCK_NOT_GRANTED)) {
                        return state.status;