X-Git-Url: https://git.saurik.com/redis.git/blobdiff_plain/aaada3f962a9f87fb239e55e3d26c1e794d411d5..1858da2faae3b6a8becf4f7eef3f712d6e4b986b:/src/t_list.c

diff --git a/src/t_list.c b/src/t_list.c
index 2a981033..ca03916b 100644
--- a/src/t_list.c
+++ b/src/t_list.c
@@ -86,7 +86,7 @@ unsigned long listTypeLength(robj *subject) {
 }
 
 /* Initialize an iterator at the specified index. */
-listTypeIterator *listTypeInitIterator(robj *subject, int index, unsigned char direction) {
+listTypeIterator *listTypeInitIterator(robj *subject, long index, unsigned char direction) {
     listTypeIterator *li = zmalloc(sizeof(listTypeIterator));
     li->subject = subject;
     li->encoding = subject->encoding;
@@ -198,7 +198,7 @@ void listTypeInsert(listTypeEntry *entry, robj *value, int where) {
 int listTypeEqual(listTypeEntry *entry, robj *o) {
     listTypeIterator *li = entry->li;
     if (li->encoding == REDIS_ENCODING_ZIPLIST) {
-        redisAssert(o->encoding == REDIS_ENCODING_RAW);
+        redisAssertWithInfo(NULL,o,o->encoding == REDIS_ENCODING_RAW);
         return ziplistCompare(entry->zi,o->ptr,sdslen(o->ptr));
     } else if (li->encoding == REDIS_ENCODING_LINKEDLIST) {
         return equalStringObjects(o,listNodeValue(entry->ln));
@@ -235,7 +235,7 @@ void listTypeDelete(listTypeEntry *entry) {
 void listTypeConvert(robj *subject, int enc) {
     listTypeIterator *li;
     listTypeEntry entry;
-    redisAssert(subject->type == REDIS_LIST);
+    redisAssertWithInfo(NULL,subject,subject->type == REDIS_LIST);
 
     if (enc == REDIS_ENCODING_LINKEDLIST) {
         list *l = listCreate();
@@ -259,29 +259,47 @@ void listTypeConvert(robj *subject, int enc) {
  *----------------------------------------------------------------------------*/
 
 void pushGenericCommand(redisClient *c, int where) {
+    int j, waiting = 0, pushed = 0;
     robj *lobj = lookupKeyWrite(c->db,c->argv[1]);
-    if (lobj == NULL) {
-        if (handleClientsWaitingListPush(c,c->argv[1],c->argv[2])) {
-            addReply(c,shared.cone);
-            return;
-        }
-        lobj = createZiplistObject();
-        dbAdd(c->db,c->argv[1],lobj);
-    } else {
-        if (lobj->type != REDIS_LIST) {
-            addReply(c,shared.wrongtypeerr);
-            return;
+    int may_have_waiting_clients = (lobj == NULL);
+
+    if (lobj && lobj->type != REDIS_LIST) {
+        addReply(c,shared.wrongtypeerr);
+        return;
+    }
+
+    for (j = 2; j < c->argc; j++) {
+        c->argv[j] = tryObjectEncoding(c->argv[j]);
+        if (may_have_waiting_clients) {
+            if (handleClientsWaitingListPush(c,c->argv[1],c->argv[j])) {
+                waiting++;
+                continue;
+            } else {
+                may_have_waiting_clients = 0;
+            }
         }
-        if (handleClientsWaitingListPush(c,c->argv[1],c->argv[2])) {
-            touchWatchedKey(c->db,c->argv[1]);
-            addReply(c,shared.cone);
-            return;
+        if (!lobj) {
+            lobj = createZiplistObject();
+            dbAdd(c->db,c->argv[1],lobj);
         }
+        listTypePush(lobj,c->argv[j],where);
+        pushed++;
+    }
+    addReplyLongLong(c, waiting + (lobj ? listTypeLength(lobj) : 0));
+    if (pushed) signalModifiedKey(c->db,c->argv[1]);
+    server.dirty += pushed;
+
+    /* Alter the replication of the command accordingly to the number of
+     * list elements delivered to clients waiting into a blocking operation.
+     * We do that only if there were waiting clients, and only if still some
+     * element was pushed into the list (othewise dirty is 0 and nothign will
+     * be propagated). */
+    if (waiting && pushed) {
+        /* CMD KEY a b C D E */
+        for (j = 0; j < waiting; j++) decrRefCount(c->argv[j+2]);
+        memmove(c->argv+2,c->argv+2+waiting,sizeof(robj*)*pushed);
+        c->argc -= waiting;
     }
-    listTypePush(lobj,c->argv[2],where);
-    addReplyLongLong(c,listTypeLength(lobj));
-    touchWatchedKey(c->db,c->argv[1]);
-    server.dirty++;
 }
 
 void lpushCommand(redisClient *c) {
@@ -304,7 +322,7 @@ void pushxGenericCommand(redisClient *c, robj *refval, robj *val, int where) {
     if (refval != NULL) {
         /* Note: we expect refval to be string-encoded because it is *not* the
          * last argument of the multi-bulk LINSERT. */
-        redisAssert(refval->encoding == REDIS_ENCODING_RAW);
+        redisAssertWithInfo(c,refval,refval->encoding == REDIS_ENCODING_RAW);
 
         /* We're not sure if this value can be inserted yet, but we cannot
          * convert the list inside the iterator. We don't want to loop over
@@ -329,7 +347,7 @@ void pushxGenericCommand(redisClient *c, robj *refval, robj *val, int where) {
             if (subject->encoding == REDIS_ENCODING_ZIPLIST &&
                 ziplistLen(subject->ptr) > server.list_max_ziplist_entries)
                     listTypeConvert(subject,REDIS_ENCODING_LINKEDLIST);
-            touchWatchedKey(c->db,c->argv[1]);
+            signalModifiedKey(c->db,c->argv[1]);
             server.dirty++;
         } else {
             /* Notify client of a failed insert */
@@ -338,22 +356,25 @@ void pushxGenericCommand(redisClient *c, robj *refval, robj *val, int where) {
         }
     } else {
         listTypePush(subject,val,where);
-        touchWatchedKey(c->db,c->argv[1]);
+        signalModifiedKey(c->db,c->argv[1]);
         server.dirty++;
     }
 
-    addReplyUlong(c,listTypeLength(subject));
+    addReplyLongLong(c,listTypeLength(subject));
 }
 
 void lpushxCommand(redisClient *c) {
+    c->argv[2] = tryObjectEncoding(c->argv[2]);
     pushxGenericCommand(c,NULL,c->argv[2],REDIS_HEAD);
 }
 
 void rpushxCommand(redisClient *c) {
+    c->argv[2] = tryObjectEncoding(c->argv[2]);
     pushxGenericCommand(c,NULL,c->argv[2],REDIS_TAIL);
 }
 
 void linsertCommand(redisClient *c) {
+    c->argv[4] = tryObjectEncoding(c->argv[4]);
     if (strcasecmp(c->argv[2]->ptr,"after") == 0) {
         pushxGenericCommand(c,c->argv[3],c->argv[4],REDIS_TAIL);
     } else if (strcasecmp(c->argv[2]->ptr,"before") == 0) {
@@ -366,15 +387,18 @@ void linsertCommand(redisClient *c) {
 void llenCommand(redisClient *c) {
     robj *o = lookupKeyReadOrReply(c,c->argv[1],shared.czero);
     if (o == NULL || checkType(c,o,REDIS_LIST)) return;
-    addReplyUlong(c,listTypeLength(o));
+    addReplyLongLong(c,listTypeLength(o));
 }
 
 void lindexCommand(redisClient *c) {
     robj *o = lookupKeyReadOrReply(c,c->argv[1],shared.nullbulk);
     if (o == NULL || checkType(c,o,REDIS_LIST)) return;
-    int index = atoi(c->argv[2]->ptr);
+    long index;
     robj *value = NULL;
 
+    if ((getLongFromObjectOrReply(c, c->argv[2], &index, NULL) != REDIS_OK))
+        return;
+
     if (o->encoding == REDIS_ENCODING_ZIPLIST) {
         unsigned char *p;
         unsigned char *vstr;
@@ -408,8 +432,11 @@ void lindexCommand(redisClient *c) {
 void lsetCommand(redisClient *c) {
     robj *o = lookupKeyWriteOrReply(c,c->argv[1],shared.nokeyerr);
     if (o == NULL || checkType(c,o,REDIS_LIST)) return;
-    int index = atoi(c->argv[2]->ptr);
-    robj *value = c->argv[3];
+    long index;
+    robj *value = (c->argv[3] = tryObjectEncoding(c->argv[3]));
+
+    if ((getLongFromObjectOrReply(c, c->argv[2], &index, NULL) != REDIS_OK))
+        return;
 
     listTypeTryConversion(o,value);
     if (o->encoding == REDIS_ENCODING_ZIPLIST) {
@@ -423,7 +450,7 @@ void lsetCommand(redisClient *c) {
             o->ptr = ziplistInsert(o->ptr,p,value->ptr,sdslen(value->ptr));
             decrRefCount(value);
             addReply(c,shared.ok);
-            touchWatchedKey(c->db,c->argv[1]);
+            signalModifiedKey(c->db,c->argv[1]);
             server.dirty++;
         }
     } else if (o->encoding == REDIS_ENCODING_LINKEDLIST) {
@@ -435,7 +462,7 @@ void lsetCommand(redisClient *c) {
             listNodeValue(ln) = value;
             incrRefCount(value);
             addReply(c,shared.ok);
-            touchWatchedKey(c->db,c->argv[1]);
+            signalModifiedKey(c->db,c->argv[1]);
             server.dirty++;
         }
     } else {
@@ -454,7 +481,7 @@ void popGenericCommand(redisClient *c, int where) {
         addReplyBulk(c,value);
         decrRefCount(value);
         if (listTypeLength(o) == 0) dbDelete(c->db,c->argv[1]);
-        touchWatchedKey(c->db,c->argv[1]);
+        signalModifiedKey(c->db,c->argv[1]);
         server.dirty++;
     }
 }
@@ -468,12 +495,11 @@ void rpopCommand(redisClient *c) {
 }
 
 void lrangeCommand(redisClient *c) {
-    robj *o, *value;
-    int start = atoi(c->argv[2]->ptr);
-    int end = atoi(c->argv[3]->ptr);
-    int llen;
-    int rangelen, j;
-    listTypeEntry entry;
+    robj *o;
+    long start, end, llen, rangelen;
+
+    if ((getLongFromObjectOrReply(c, c->argv[2], &start, NULL) != REDIS_OK) ||
+        (getLongFromObjectOrReply(c, c->argv[3], &end, NULL) != REDIS_OK)) return;
 
     if ((o = lookupKeyReadOrReply(c,c->argv[1],shared.emptymultibulk)) == NULL
          || checkType(c,o,REDIS_LIST)) return;
@@ -494,26 +520,48 @@ void lrangeCommand(redisClient *c) {
     rangelen = (end-start)+1;
 
     /* Return the result in form of a multi-bulk reply */
-    addReplySds(c,sdscatprintf(sdsempty(),"*%d\r\n",rangelen));
-    listTypeIterator *li = listTypeInitIterator(o,start,REDIS_TAIL);
-    for (j = 0; j < rangelen; j++) {
-        redisAssert(listTypeNext(li,&entry));
-        value = listTypeGet(&entry);
-        addReplyBulk(c,value);
-        decrRefCount(value);
+    addReplyMultiBulkLen(c,rangelen);
+    if (o->encoding == REDIS_ENCODING_ZIPLIST) {
+        unsigned char *p = ziplistIndex(o->ptr,start);
+        unsigned char *vstr;
+        unsigned int vlen;
+        long long vlong;
+
+        while(rangelen--) {
+            ziplistGet(p,&vstr,&vlen,&vlong);
+            if (vstr) {
+                addReplyBulkCBuffer(c,vstr,vlen);
+            } else {
+                addReplyBulkLongLong(c,vlong);
+            }
+            p = ziplistNext(o->ptr,p);
+        }
+    } else if (o->encoding == REDIS_ENCODING_LINKEDLIST) {
+        listNode *ln;
+
+        /* If we are nearest to the end of the list, reach the element
+         * starting from tail and going backward, as it is faster. */
+        if (start > llen/2) start -= llen;
+        ln = listIndex(o->ptr,start);
+
+        while(rangelen--) {
+            addReplyBulk(c,ln->value);
+            ln = ln->next;
+        }
+    } else {
+        redisPanic("List encoding is not LINKEDLIST nor ZIPLIST!");
     }
-    listTypeReleaseIterator(li);
 }
 
 void ltrimCommand(redisClient *c) {
     robj *o;
-    int start = atoi(c->argv[2]->ptr);
-    int end = atoi(c->argv[3]->ptr);
-    int llen;
-    int j, ltrim, rtrim;
+    long start, end, llen, j, ltrim, rtrim;
     list *list;
     listNode *ln;
 
+    if ((getLongFromObjectOrReply(c, c->argv[2], &start, NULL) != REDIS_OK) ||
+        (getLongFromObjectOrReply(c, c->argv[3], &end, NULL) != REDIS_OK)) return;
+
     if ((o = lookupKeyWriteOrReply(c,c->argv[1],shared.ok)) == NULL ||
         checkType(c,o,REDIS_LIST)) return;
     llen = listTypeLength(o);
@@ -553,17 +601,21 @@ void ltrimCommand(redisClient *c) {
         redisPanic("Unknown list encoding");
     }
     if (listTypeLength(o) == 0) dbDelete(c->db,c->argv[1]);
-    touchWatchedKey(c->db,c->argv[1]);
+    signalModifiedKey(c->db,c->argv[1]);
     server.dirty++;
     addReply(c,shared.ok);
 }
 
 void lremCommand(redisClient *c) {
-    robj *subject, *obj = c->argv[3];
-    int toremove = atoi(c->argv[2]->ptr);
-    int removed = 0;
+    robj *subject, *obj;
+    obj = c->argv[3] = tryObjectEncoding(c->argv[3]);
+    long toremove;
+    long removed = 0;
     listTypeEntry entry;
 
+    if ((getLongFromObjectOrReply(c, c->argv[2], &toremove, NULL) != REDIS_OK))
+        return;
+
     subject = lookupKeyWriteOrReply(c,c->argv[1],shared.czero);
     if (subject == NULL || checkType(c,subject,REDIS_LIST)) return;
 
@@ -594,58 +646,88 @@ void lremCommand(redisClient *c) {
         decrRefCount(obj);
 
     if (listTypeLength(subject) == 0) dbDelete(c->db,c->argv[1]);
-    addReplySds(c,sdscatprintf(sdsempty(),":%d\r\n",removed));
-    if (removed) touchWatchedKey(c->db,c->argv[1]);
+    addReplyLongLong(c,removed);
+    if (removed) signalModifiedKey(c->db,c->argv[1]);
 }
 
 /* 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 rpoplpushcommand(redisClient *c) {
+
+void rpoplpushHandlePush(redisClient *origclient, redisClient *c, robj *dstkey, robj *dstobj, robj *value) {
+    if (!handleClientsWaitingListPush(origclient,dstkey,value)) {
+        /* Create the list if the key does not exist */
+        if (!dstobj) {
+            dstobj = createZiplistObject();
+            dbAdd(c->db,dstkey,dstobj);
+        } else {
+            signalModifiedKey(c->db,dstkey);
+        }
+        listTypePush(dstobj,value,REDIS_HEAD);
+        /* Additionally propagate this PUSH operation together with
+         * the operation performed by the command. */
+        {
+            robj **argv = zmalloc(sizeof(robj*)*3);
+            argv[0] = createStringObject("LPUSH",5);
+            argv[1] = dstkey;
+            argv[2] = value;
+            incrRefCount(argv[1]);
+            incrRefCount(argv[2]);
+            alsoPropagate(server.lpushCommand,c->db->id,argv,3,
+                          REDIS_PROPAGATE_AOF|REDIS_PROPAGATE_REPL);
+        }
+    }
+    /* 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 ||
         checkType(c,sobj,REDIS_LIST)) return;
 
     if (listTypeLength(sobj) == 0) {
+        /* This may only happen after loading very old RDB files. Recent
+         * versions of Redis delete keys of empty lists. */
         addReply(c,shared.nullbulk);
     } else {
         robj *dobj = lookupKeyWrite(c->db,c->argv[2]);
+        robj *touchedkey = c->argv[1];
+
         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);
+        /* We saved touched key, and protect it, since rpoplpushHandlePush
+         * may change the client command argument vector. */
+        incrRefCount(touchedkey);
+        rpoplpushHandlePush(c,c,c->argv[2],dobj,value);
 
         /* listTypePop returns an object with its refcount incremented */
         decrRefCount(value);
 
         /* Delete the source list when it is empty */
-        if (listTypeLength(sobj) == 0) dbDelete(c->db,c->argv[1]);
-        touchWatchedKey(c->db,c->argv[1]);
+        if (listTypeLength(sobj) == 0) dbDelete(c->db,touchedkey);
+        signalModifiedKey(c->db,touchedkey);
+        decrRefCount(touchedkey);
         server.dirty++;
+
+        /* Replicate this as a simple RPOP since the LPUSH side is replicated
+         * by rpoplpushHandlePush() call if needed (it may not be needed
+         * if a client is blocking wait a push against the list). */
+        rewriteClientCommandVector(c,2,
+            resetRefCount(createStringObject("RPOP",4)),
+            c->argv[1]);
     }
 }
 
@@ -684,17 +766,23 @@ void rpoplpushcommand(redisClient *c) {
 
 /* Set a client in blocking mode for the specified key, with the specified
  * timeout */
-void blockForKeys(redisClient *c, robj **keys, int numkeys, time_t timeout) {
+void blockForKeys(redisClient *c, robj **keys, int numkeys, time_t timeout, robj *target) {
     dictEntry *de;
     list *l;
     int j;
 
-    c->blocking_keys = zmalloc(sizeof(robj*)*numkeys);
-    c->blocking_keys_num = numkeys;
-    c->blockingto = timeout;
+    c->bpop.keys = zmalloc(sizeof(robj*)*numkeys);
+    c->bpop.count = numkeys;
+    c->bpop.timeout = timeout;
+    c->bpop.target = target;
+
+    if (target != NULL) {
+        incrRefCount(target);
+    }
+
     for (j = 0; j < numkeys; j++) {
         /* Add the key in the client structure, to map clients -> keys */
-        c->blocking_keys[j] = keys[j];
+        c->bpop.keys[j] = keys[j];
         incrRefCount(keys[j]);
 
         /* And in the other "side", to map keys -> clients */
@@ -706,15 +794,15 @@ void blockForKeys(redisClient *c, robj **keys, int numkeys, time_t timeout) {
             l = listCreate();
             retval = dictAdd(c->db->blocking_keys,keys[j],l);
             incrRefCount(keys[j]);
-            redisAssert(retval == DICT_OK);
+            redisAssertWithInfo(c,keys[j],retval == DICT_OK);
         } else {
-            l = dictGetEntryVal(de);
+            l = dictGetVal(de);
         }
         listAddNodeTail(l,c);
     }
     /* Mark the client as a blocked client */
     c->flags |= REDIS_BLOCKED;
-    server.blpop_blocked_clients++;
+    server.bpop_blocked_clients++;
 }
 
 /* Unblock a client that's waiting in a blocking operation such as BLPOP */
@@ -723,30 +811,29 @@ void unblockClientWaitingData(redisClient *c) {
     list *l;
     int j;
 
-    redisAssert(c->blocking_keys != NULL);
+    redisAssertWithInfo(c,NULL,c->bpop.keys != NULL);
     /* The client may wait for multiple keys, so unblock it for every key. */
-    for (j = 0; j < c->blocking_keys_num; j++) {
+    for (j = 0; j < c->bpop.count; j++) {
         /* Remove this client from the list of clients waiting for this key. */
-        de = dictFind(c->db->blocking_keys,c->blocking_keys[j]);
-        redisAssert(de != NULL);
-        l = dictGetEntryVal(de);
+        de = dictFind(c->db->blocking_keys,c->bpop.keys[j]);
+        redisAssertWithInfo(c,c->bpop.keys[j],de != NULL);
+        l = dictGetVal(de);
         listDelNode(l,listSearchKey(l,c));
         /* If the list is empty we need to remove it to avoid wasting memory */
         if (listLength(l) == 0)
-            dictDelete(c->db->blocking_keys,c->blocking_keys[j]);
-        decrRefCount(c->blocking_keys[j]);
+            dictDelete(c->db->blocking_keys,c->bpop.keys[j]);
+        decrRefCount(c->bpop.keys[j]);
     }
+
     /* Cleanup the client structure */
-    zfree(c->blocking_keys);
-    c->blocking_keys = NULL;
-    c->flags &= (~REDIS_BLOCKED);
-    server.blpop_blocked_clients--;
-    /* We want to process data if there is some command waiting
-     * in the input buffer. Note that this is safe even if
-     * unblockClientWaitingData() gets called from freeClient() because
-     * freeClient() will be smart enough to call this function
-     * *after* c->querybuf was set to NULL. */
-    if (c->querybuf && sdslen(c->querybuf) > 0) processInputBuffer(c);
+    zfree(c->bpop.keys);
+    c->bpop.keys = NULL;
+    if (c->bpop.target) decrRefCount(c->bpop.target);
+    c->bpop.target = NULL;
+    c->flags &= ~REDIS_BLOCKED;
+    c->flags |= REDIS_UNBLOCKED;
+    server.bpop_blocked_clients--;
+    listAddNodeTail(server.unblocked_clients,c);
 }
 
 /* This should be called from any function PUSHing into lists.
@@ -762,21 +849,73 @@ void unblockClientWaitingData(redisClient *c) {
 int handleClientsWaitingListPush(redisClient *c, robj *key, robj *ele) {
     struct dictEntry *de;
     redisClient *receiver;
-    list *l;
+    int numclients;
+    list *clients;
     listNode *ln;
+    robj *dstkey, *dstobj;
 
     de = dictFind(c->db->blocking_keys,key);
     if (de == NULL) return 0;
-    l = dictGetEntryVal(de);
-    ln = listFirst(l);
-    redisAssert(ln != NULL);
-    receiver = ln->value;
+    clients = dictGetVal(de);
+    numclients = listLength(clients);
+
+    /* Try to handle the push as long as there are clients waiting for a push.
+     * Note that "numclients" is used because the list of clients waiting for a
+     * push on "key" is deleted by unblockClient() when empty.
+     *
+     * This loop will have more than 1 iteration when there is a BRPOPLPUSH
+     * that cannot push the target list because it does not contain a list. If
+     * this happens, it simply tries the next client waiting for a push. */
+    while (numclients--) {
+        ln = listFirst(clients);
+        redisAssertWithInfo(c,key,ln != NULL);
+        receiver = ln->value;
+        dstkey = receiver->bpop.target;
+
+        /* Protect receiver->bpop.target, that will be freed by
+         * the next unblockClientWaitingData() call. */
+        if (dstkey) incrRefCount(dstkey);
+
+        /* This should remove the first element of the "clients" list. */
+        unblockClientWaitingData(receiver);
+
+        if (dstkey == NULL) {
+            /* BRPOP/BLPOP */
+            addReplyMultiBulkLen(receiver,2);
+            addReplyBulk(receiver,key);
+            addReplyBulk(receiver,ele);
+            return 1; /* Serve just the first client as in B[RL]POP semantics */
+        } else {
+            /* BRPOPLPUSH, note that receiver->db is always equal to c->db. */
+            dstobj = lookupKeyWrite(receiver->db,dstkey);
+            if (!(dstobj && checkType(receiver,dstobj,REDIS_LIST))) {
+                rpoplpushHandlePush(c,receiver,dstkey,dstobj,ele);
+                decrRefCount(dstkey);
+                return 1;
+            }
+            decrRefCount(dstkey);
+        }
+    }
+
+    return 0;
+}
+
+int getTimeoutFromObjectOrReply(redisClient *c, robj *object, time_t *timeout) {
+    long tval;
+
+    if (getLongFromObjectOrReply(c,object,&tval,
+        "timeout is not an integer or out of range") != REDIS_OK)
+        return REDIS_ERR;
+
+    if (tval < 0) {
+        addReplyError(c,"timeout is negative");
+        return REDIS_ERR;
+    }
+
+    if (tval > 0) tval += server.unixtime;
+    *timeout = tval;
 
-    addReplySds(receiver,sdsnew("*2\r\n"));
-    addReplyBulk(receiver,key);
-    addReplyBulk(receiver,ele);
-    unblockClientWaitingData(receiver);
-    return 1;
+    return REDIS_OK;
 }
 
 /* Blocking RPOP/LPOP */
@@ -785,6 +924,9 @@ void blockingPopGenericCommand(redisClient *c, int where) {
     time_t timeout;
     int j;
 
+    if (getTimeoutFromObjectOrReply(c,c->argv[c->argc-1],&timeout) != REDIS_OK)
+        return;
+
     for (j = 1; j < c->argc-1; j++) {
         o = lookupKeyWrite(c->db,c->argv[j]);
         if (o != NULL) {
@@ -793,40 +935,37 @@ void blockingPopGenericCommand(redisClient *c, int where) {
                 return;
             } else {
                 if (listTypeLength(o) != 0) {
-                    /* If the list contains elements fall back to the usual
-                     * non-blocking POP operation */
-                    robj *argv[2], **orig_argv;
-                    int orig_argc;
-
-                    /* We need to alter the command arguments before to call
-                     * popGenericCommand() as the command takes a single key. */
-                    orig_argv = c->argv;
-                    orig_argc = c->argc;
-                    argv[1] = c->argv[j];
-                    c->argv = argv;
-                    c->argc = 2;
-
-                    /* Also the return value is different, we need to output
-                     * the multi bulk reply header and the key name. The
-                     * "real" command will add the last element (the value)
-                     * for us. If this souds like an hack to you it's just
-                     * because it is... */
-                    addReplySds(c,sdsnew("*2\r\n"));
-                    addReplyBulk(c,argv[1]);
-                    popGenericCommand(c,where);
-
-                    /* Fix the client structure with the original stuff */
-                    c->argv = orig_argv;
-                    c->argc = orig_argc;
+                    /* Non empty list, this is like a non normal [LR]POP. */
+                    robj *value = listTypePop(o,where);
+                    redisAssert(value != NULL);
+
+                    addReplyMultiBulkLen(c,2);
+                    addReplyBulk(c,c->argv[j]);
+                    addReplyBulk(c,value);
+                    decrRefCount(value);
+                    if (listTypeLength(o) == 0) dbDelete(c->db,c->argv[j]);
+                    signalModifiedKey(c->db,c->argv[j]);
+                    server.dirty++;
+
+                    /* Replicate it as an [LR]POP instead of B[LR]POP. */
+                    rewriteClientCommandVector(c,2,
+                        (where == REDIS_HEAD) ? shared.lpop : shared.rpop,
+                        c->argv[j]);
                     return;
                 }
             }
         }
     }
+
+    /* If we are inside a MULTI/EXEC and the list is empty the only thing
+     * we can do is treating it as a timeout (even with timeout 0). */
+    if (c->flags & REDIS_MULTI) {
+        addReply(c,shared.nullmultibulk);
+        return;
+    }
+
     /* If the list is empty or the key does not exists we must block */
-    timeout = strtol(c->argv[c->argc-1]->ptr,NULL,10);
-    if (timeout > 0) timeout += time(NULL);
-    blockForKeys(c,c->argv+1,c->argc-2,timeout);
+    blockForKeys(c, c->argv + 1, c->argc - 2, timeout, NULL);
 }
 
 void blpopCommand(redisClient *c) {
@@ -836,3 +975,34 @@ void blpopCommand(redisClient *c) {
 void brpopCommand(redisClient *c) {
     blockingPopGenericCommand(c,REDIS_TAIL);
 }
+
+void brpoplpushCommand(redisClient *c) {
+    time_t timeout;
+
+    if (getTimeoutFromObjectOrReply(c,c->argv[3],&timeout) != REDIS_OK)
+        return;
+
+    robj *key = lookupKeyWrite(c->db, c->argv[1]);
+
+    if (key == NULL) {
+        if (c->flags & REDIS_MULTI) {
+
+            /* Blocking against an empty list in a multi state
+             * returns immediately. */
+            addReply(c, shared.nullbulk);
+        } else {
+            /* The list is empty and the client blocks. */
+            blockForKeys(c, c->argv + 1, 1, timeout, c->argv[2]);
+        }
+    } else {
+        if (key->type != REDIS_LIST) {
+            addReply(c, shared.wrongtypeerr);
+        } else {
+
+            /* The list exists and has elements, so
+             * the regular rpoplpushCommand is executed. */
+            redisAssertWithInfo(c,key,listTypeLength(key) > 0);
+            rpoplpushCommand(c);
+        }
+    }
+}