uci: introduce confirm method to cancel pending rollbacks without side effects

Calling commit with rollback=false to cancel a pending rollback timer can
potentially trigger another commit if no rollback is actually pending.

This introduces a new method "confirm" which cancels the rollback timer
without any other possible side effects.

While being at it, change the return code when trying to commit during
a pending rollback or when trying to rollback without a pending timeout to
UBUS_STATUS_NO_DATA. This is needed to be able to differentiate between a
denied request and an inappropriate state.

Also change the error return code for glob() failures to the more
appropriate UBUS_STATUS_NOT_FOUND.

Signed-off-by: Jo-Philipp Wich <jow@openwrt.org>

diff --git a/uci.c b/uci.c
index 9be0aaa8f3b8d7403b28a5e995819a54dbf19ebe..f1dd120f910fba045098b064644d984a6ce10419 100644 (file)
--- a/uci.c
+++ b/uci.c
@@ -1382,7 +1382,7 @@ rpc_uci_apply(struct ubus_context *ctx, struct ubus_object *obj,
 
                snprintf(tmp, sizeof(tmp), RPC_UCI_SAVEDIR_PREFIX "%s/*", sid);
                if (glob(tmp, GLOB_PERIOD, NULL, &gl) < 0)
-                       return -1;
+                       return UBUS_STATUS_NOT_FOUND;
 
                snprintf(tmp, sizeof(tmp), RPC_UCI_SAVEDIR_PREFIX "%s/", sid);
 
@@ -1409,20 +1409,31 @@ rpc_uci_apply(struct ubus_context *ctx, struct ubus_object *obj,
 
                globfree(&gl);
 
-               apply_running = true;
-               apply_timer.cb = rpc_uci_apply_timeout;
-               uloop_timeout_set(&apply_timer, timeout * 1000);
-               apply_ctx = ctx;
+               if (rollback) {
+                       apply_running = true;
+                       apply_timer.cb = rpc_uci_apply_timeout;
+                       uloop_timeout_set(&apply_timer, timeout * 1000);
+                       apply_ctx = ctx;
+               }
        }
 
-       if (apply_running && !rollback) {
-               rpc_uci_purge_dir(RPC_SNAPSHOT_FILES);
-               rpc_uci_purge_dir(RPC_SNAPSHOT_DELTA);
+       return 0;
+}
 
-               uloop_timeout_cancel(&apply_timer);
-               apply_running = false;
-               apply_ctx = NULL;
-       }
+static int
+rpc_uci_confirm(struct ubus_context *ctx, struct ubus_object *obj,
+                struct ubus_request_data *req, const char *method,
+                struct blob_attr *msg)
+{
+       if (!apply_running)
+               return UBUS_STATUS_NO_DATA;
+
+       rpc_uci_purge_dir(RPC_SNAPSHOT_FILES);
+       rpc_uci_purge_dir(RPC_SNAPSHOT_DELTA);
+
+       uloop_timeout_cancel(&apply_timer);
+       apply_running = false;
+       apply_ctx = NULL;
 
        return 0;
 }
@@ -1442,7 +1453,7 @@ rpc_uci_rollback(struct ubus_context *ctx, struct ubus_object *obj,
                      blob_data(msg), blob_len(msg));
 
        if (!apply_running)
-               return UBUS_STATUS_PERMISSION_DENIED;
+               return UBUS_STATUS_NO_DATA;
 
        if (!tb[RPC_B_SESSION])
                return UBUS_STATUS_INVALID_ARGUMENT;
@@ -1451,7 +1462,7 @@ rpc_uci_rollback(struct ubus_context *ctx, struct ubus_object *obj,
 
        snprintf(tmp, sizeof(tmp), "%s/*", RPC_SNAPSHOT_FILES);
        if (glob(tmp, GLOB_PERIOD, NULL, &gl) < 0)
-               return -1;
+               return UBUS_STATUS_NOT_FOUND;
 
        ret = rpc_uci_apply_access(sid, &gl);
        if (ret) {
@@ -1512,6 +1523,7 @@ int rpc_uci_api_init(struct ubus_context *ctx)
                UBUS_METHOD("revert",   rpc_uci_revert,   rpc_uci_config_policy),
                UBUS_METHOD("commit",   rpc_uci_commit,   rpc_uci_config_policy),
                UBUS_METHOD("apply",    rpc_uci_apply,    rpc_uci_apply_policy),
+               UBUS_METHOD("confirm",  rpc_uci_confirm,  rpc_uci_rollback_policy),
                UBUS_METHOD("rollback", rpc_uci_rollback, rpc_uci_rollback_policy),
        };