X-Git-Url: https://git.saurik.com/redis.git/blobdiff_plain/75b41de8ca975d01c6371a98f9e552c934af5937..f96a8a8054b3b699c2fba797bdcd203dda1168ce:/src/t_list.c diff --git a/src/t_list.c b/src/t_list.c index 42e1d587..71436198 100644 --- a/src/t_list.c +++ b/src/t_list.c @@ -259,30 +259,35 @@ void listTypeConvert(robj *subject, int enc) { *----------------------------------------------------------------------------*/ void pushGenericCommand(redisClient *c, int where) { + int j, addlen = 0, pushed = 0; robj *lobj = lookupKeyWrite(c->db,c->argv[1]); - c->argv[2] = tryObjectEncoding(c->argv[2]); - 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])) { + addlen++; + 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++; } - listTypePush(lobj,c->argv[2],where); - addReplyLongLong(c,listTypeLength(lobj)); - touchWatchedKey(c->db,c->argv[1]); - server.dirty++; + addReplyLongLong(c,addlen + (lobj ? listTypeLength(lobj) : 0)); + if (pushed) signalModifiedKey(c->db,c->argv[1]); + server.dirty += pushed; } void lpushCommand(redisClient *c) { @@ -330,7 +335,7 @@ 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 */ @@ -339,7 +344,7 @@ 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++; } @@ -427,7 +432,7 @@ 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) { @@ -439,7 +444,7 @@ 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 { @@ -458,7 +463,7 @@ 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++; } } @@ -472,12 +477,11 @@ void rpopCommand(redisClient *c) { } void lrangeCommand(redisClient *c) { - robj *o, *value; + robj *o; int start = atoi(c->argv[2]->ptr); int end = atoi(c->argv[3]->ptr); int llen; - int rangelen, j; - listTypeEntry entry; + int rangelen; if ((o = lookupKeyReadOrReply(c,c->argv[1],shared.emptymultibulk)) == NULL || checkType(c,o,REDIS_LIST)) return; @@ -499,14 +503,36 @@ void lrangeCommand(redisClient *c) { /* Return the result in form of a multi-bulk reply */ addReplyMultiBulkLen(c,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); + 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) { @@ -557,7 +583,7 @@ 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); } @@ -600,25 +626,63 @@ void lremCommand(redisClient *c) { if (listTypeLength(subject) == 0) dbDelete(c->db,c->argv[1]); addReplyLongLong(c,removed); - if (removed) touchWatchedKey(c->db,c->argv[1]); + 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) { + robj *aux; + + 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); + /* If we are pushing as a result of LPUSH against a key + * watched by BRPOPLPUSH, we need to rewrite the command vector + * as an LPUSH. + * + * If this is called directly by RPOPLPUSH (either directly + * or via a BRPOPLPUSH where the popped list exists) + * we should replicate the RPOPLPUSH command itself. */ + if (c != origclient) { + aux = createStringObject("LPUSH",5); + rewriteClientCommandVector(origclient,3,aux,dstkey,value); + decrRefCount(aux); + } else { + /* Make sure to always use RPOPLPUSH in the replication / AOF, + * even if the original command was BRPOPLPUSH. */ + aux = createStringObject("RPOPLPUSH",9); + rewriteClientCommandVector(origclient,3,aux,c->argv[1],c->argv[2]); + decrRefCount(aux); + } + server.dirty++; + } + + /* 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; @@ -627,29 +691,22 @@ void rpoplpushcommand(redisClient *c) { 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++; } } @@ -689,17 +746,23 @@ 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 */ @@ -719,7 +782,7 @@ void blockForKeys(redisClient *c, robj **keys, int numkeys, time_t timeout) { } /* 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 */ @@ -728,30 +791,29 @@ void unblockClientWaitingData(redisClient *c) { list *l; int j; - redisAssert(c->blocking_keys != NULL); + redisAssert(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]); + de = dictFind(c->db->blocking_keys,c->bpop.keys[j]); redisAssert(de != NULL); l = dictGetEntryVal(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. @@ -767,39 +829,83 @@ 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 = dictGetEntryVal(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); + redisAssert(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 += time(NULL); + *timeout = tval; - addReplyMultiBulkLen(receiver,2); - addReplyBulk(receiver,key); - addReplyBulk(receiver,ele); - unblockClientWaitingData(receiver); - return 1; + return REDIS_OK; } /* Blocking RPOP/LPOP */ void blockingPopGenericCommand(redisClient *c, int where) { robj *o; - long long lltimeout; time_t timeout; int j; - /* Make sure timeout is an integer value */ - if (getLongLongFromObjectOrReply(c,c->argv[c->argc-1],&lltimeout, - "timeout is not an integer") != REDIS_OK) return; - - /* Make sure the timeout is not negative */ - if (lltimeout < 0) { - addReplyError(c,"timeout is negative"); + 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]); @@ -811,6 +917,7 @@ void blockingPopGenericCommand(redisClient *c, int where) { if (listTypeLength(o) != 0) { /* If the list contains elements fall back to the usual * non-blocking POP operation */ + struct redisCommand *orig_cmd; robj *argv[2], **orig_argv; int orig_argc; @@ -818,6 +925,7 @@ void blockingPopGenericCommand(redisClient *c, int where) { * popGenericCommand() as the command takes a single key. */ orig_argv = c->argv; orig_argc = c->argc; + orig_cmd = c->cmd; argv[1] = c->argv[j]; c->argv = argv; c->argc = 2; @@ -829,11 +937,14 @@ void blockingPopGenericCommand(redisClient *c, int where) { * because it is... */ addReplyMultiBulkLen(c,2); addReplyBulk(c,argv[1]); + popGenericCommand(c,where); /* Fix the client structure with the original stuff */ c->argv = orig_argv; c->argc = orig_argc; + c->cmd = orig_cmd; + return; } } @@ -848,9 +959,7 @@ void blockingPopGenericCommand(redisClient *c, int where) { } /* If the list is empty or the key does not exists we must block */ - timeout = lltimeout; - 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) { @@ -860,3 +969,34 @@ 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. */ + redisAssert(listTypeLength(key) > 0); + rpoplpushCommand(c); + } + } +}