Move code for pushing on a (blocking) RPOPLPUSH

src/t_list.c

@@ -605,19 +605,37 @@ void lremCommand(redisClient *c) {
 
 /* This is the semantic of this command:
  *  RPOPLPUSH srclist dstlist:
- *   IF LLEN(srclist) > 0
- *     element = RPOP srclist
- *     LPUSH dstlist element
- *     RETURN element
- *   ELSE
- *     RETURN nil
- *   END
+ *    IF LLEN(srclist) > 0
+ *      element = RPOP srclist
+ *      LPUSH dstlist element
+ *      RETURN element
+ *    ELSE
+ *      RETURN nil
+ *    END
  *  END
  *
  * The idea is to be able to get an element from a list in a reliable way
  * since the element is not just returned but pushed against another list
  * as well. This command was originally proposed by Ezra Zygmuntowicz.
  */
+
+void rpoplpushHandlePush(redisClient *c, robj *dstkey, robj *dstobj, robj *value) {
+    if (!handleClientsWaitingListPush(c,dstkey,value)) {
+        /* Create the list if the key does not exist */
+        if (!dstobj) {
+            dstobj = createZiplistObject();
+            dbAdd(c->db,dstkey,dstobj);
+        } else {
+            touchWatchedKey(c->db,dstkey);
+            server.dirty++;
+        }
+        listTypePush(dstobj,value,REDIS_HEAD);
+    }
+
+    /* Always send the pushed value to the client. */
+    addReplyBulk(c,value);
+}
+
 void rpoplpushCommand(redisClient *c) {
     robj *sobj, *value;
     if ((sobj = lookupKeyWriteOrReply(c,c->argv[1],shared.nullbulk)) == NULL ||
@@ -629,20 +647,7 @@ void rpoplpushCommand(redisClient *c) {
         robj *dobj = lookupKeyWrite(c->db,c->argv[2]);
         if (dobj && checkType(c,dobj,REDIS_LIST)) return;
         value = listTypePop(sobj,REDIS_TAIL);
-
-        /* Add the element to the target list (unless it's directly
-         * passed to some BLPOP-ing client */
-        if (!handleClientsWaitingListPush(c,c->argv[2],value)) {
-            /* Create the list if the key does not exist */
-            if (!dobj) {
-                dobj = createZiplistObject();
-                dbAdd(c->db,c->argv[2],dobj);
-            }
-            listTypePush(dobj,value,REDIS_HEAD);
-        }
-
-        /* Send the element to the client as reply as well */
-        addReplyBulk(c,value);
+        rpoplpushHandlePush(c,c->argv[2],dobj,value);
 
         /* listTypePop returns an object with its refcount incremented */
         decrRefCount(value);
@@ -799,18 +804,7 @@ int handleClientsWaitingListPush(redisClient *c, robj *key, robj *ele) {
         /* BRPOPLPUSH */
         robj *dobj = lookupKeyWrite(receiver->db,target);
         if (dobj && checkType(receiver,dobj,REDIS_LIST)) return 0;
-
-        addReplyBulk(receiver,ele);
-
-        if (!handleClientsWaitingListPush(receiver, target, ele)) {
-            /* Create the list if the key does not exist */
-            if (!dobj) {
-                dobj = createZiplistObject();
-                dbAdd(receiver->db, target, dobj);
-            }
-            listTypePush(dobj, ele, REDIS_HEAD);
-        }
-
+        rpoplpushHandlePush(receiver,target,dobj,ele);
         decrRefCount(target);
     }