/*	模式订阅,即设置客户端订阅某模式。如果订阅成功则返回1,如果客户端已经订阅了该模式则返回0。*/
int pubsubSubscribePattern(redisClient *c, robj *pattern) {
    int retval = 0;

    // 先在客户端的c->pubsub_patterns链表中查找,判断客户端是否已经订阅了该模式
    if (listSearchKey(c->pubsub_patterns,pattern) == NULL) {
    	// 客户端并没有订阅该模式
        retval = 1;
        pubsubPattern *pat;
        // 将制定模式添加到c->pubsub_patterns链表中
        listAddNodeTail(c->pubsub_patterns,pattern);
        incrRefCount(pattern);
        pat = zmalloc(sizeof(*pat));
        pat->pattern = getDecodedObject(pattern);
        pat->client = c;
        // 将pubsubPattern结构添加到server.pubsub_patterns链表中
        listAddNodeTail(server.pubsub_patterns,pat);
    }
    /* Notify the client */
    // 回复客户端
    addReply(c,shared.mbulkhdr[3]);
    // 回复“psubscribe”字符串
    addReply(c,shared.psubscribebulk);
    // 回复被订阅的模式字符串
    addReplyBulk(c,pattern);
    // 回复客户端订阅的频道和模式总数目
    addReplyLongLong(c,clientSubscriptionsCount(c));
    return retval;
}
Beispiel #2
0
void getsetCommand(redisClient *c) {
    if (getGenericCommand(c) == REDIS_ERR) return;
    dbReplace(c->db,c->argv[1],c->argv[2]);
    incrRefCount(c->argv[2]);
    server.dirty++;
    removeExpire(c->db,c->argv[1]);
}
Beispiel #3
0
void msetGenericCommand(redisClient *c, int nx) {
    int j, busykeys = 0;

    if ((c->argc % 2) == 0) {
        addReplySds(c,sdsnew("-ERR wrong number of arguments for MSET\r\n"));
        return;
    }
    /* Handle the NX flag. The MSETNX semantic is to return zero and don't
     * set nothing at all if at least one already key exists. */
    if (nx) {
        for (j = 1; j < c->argc; j += 2) {
            if (lookupKeyWrite(c->db,c->argv[j]) != NULL) {
                busykeys++;
            }
        }
    }
    if (busykeys) {
        addReply(c, shared.czero);
        return;
    }

    for (j = 1; j < c->argc; j += 2) {
        c->argv[j+1] = tryObjectEncoding(c->argv[j+1]);
        dbReplace(c->db,c->argv[j],c->argv[j+1]);
        incrRefCount(c->argv[j+1]);
        removeExpire(c->db,c->argv[j]);
    }
    server.dirty += (c->argc-1)/2;
    addReply(c, nx ? shared.cone : shared.ok);
}
Beispiel #4
0
void replicationFeedSlaves(list *slaves, int dictid, robj **argv, int argc) {
    listNode *ln;
    listIter li;
    int j;

    listRewind(slaves,&li);
    while((ln = listNext(&li))) {
        redisClient *slave = ln->value;

        /* Don't feed slaves that are still waiting for BGSAVE to start */
        if (slave->replstate == REDIS_REPL_WAIT_BGSAVE_START) continue;

        /* Feed slaves that are waiting for the initial SYNC (so these commands
         * are queued in the output buffer until the intial SYNC completes),
         * or are already in sync with the master. */
        if (slave->slaveseldb != dictid) {
            robj *selectcmd;

            if (dictid >= 0 && dictid < REDIS_SHARED_SELECT_CMDS) {
                selectcmd = shared.select[dictid];
                incrRefCount(selectcmd);
            } else {
                selectcmd = createObject(REDIS_STRING,
                    sdscatprintf(sdsempty(),"select %d\r\n",dictid));
            }
            addReply(slave,selectcmd);
            decrRefCount(selectcmd);
            slave->slaveseldb = dictid;
        }
        addReplyMultiBulkLen(slave,argc);
        for (j = 0; j < argc; j++) addReplyBulk(slave,argv[j]);
    }
}
Beispiel #5
0
/* Higher level function of hashTypeGet*() that always returns a Redis
 * object (either new or with refcount incremented), so that the caller
 * can retain a reference or call decrRefCount after the usage.
 *
 * The lower level function can prevent copy on write so it is
 * the preferred way of doing read operations. */
robj *hashTypeGetObject(robj *o, robj *field) {
    robj *value = NULL;

    if (o->encoding == REDIS_ENCODING_ZIPLIST) {
        unsigned char *vstr = NULL;
        unsigned int vlen = UINT_MAX;
        long long vll = LLONG_MAX;

        if (hashTypeGetFromZiplist(o, field, &vstr, &vlen, &vll) == 0) {
            if (vstr) {
                value = createStringObject((char*)vstr, vlen);
            } else {
                value = createStringObjectFromLongLong(vll);
            }
        }

    } else if (o->encoding == REDIS_ENCODING_HT) {
        robj *aux;

        if (hashTypeGetFromHashTable(o, field, &aux) == 0) {
            incrRefCount(aux);
            value = aux;
        }
    } else {
        logicError("Unknown hash encoding");
    }
    return value;
}
Beispiel #6
0
void renameGenericCommand(redisClient *c, int nx) {
    robj *o;
    long long expire;

    /* To use the same key as src and dst is probably an error */
    if (sdscmp(c->argv[1]->ptr,c->argv[2]->ptr) == 0) {
        addReply(c,shared.sameobjecterr);
        return;
    }

    if ((o = lookupKeyWriteOrReply(c,c->argv[1],shared.nokeyerr)) == NULL)
        return;

    incrRefCount(o);
    expire = getExpire(c->db,c->argv[1]);
    if (lookupKeyWrite(c->db,c->argv[2]) != NULL) {
        if (nx) {
            decrRefCount(o);
            addReply(c,shared.czero);
            return;
        }
        /* Overwrite: delete the old key before creating the new one with the same name. */
        dbDelete(c->db,c->argv[2]);
    }
    dbAdd(c->db,c->argv[2],o);
    if (expire != -1) setExpire(c->db,c->argv[2],expire);
    dbDelete(c->db,c->argv[1]);
    signalModifiedKey(c->db,c->argv[1]);
    signalModifiedKey(c->db,c->argv[2]);
    server.dirty++;
    addReply(c,nx ? shared.cone : shared.ok);
}
Beispiel #7
0
/* Define a lua function with the specified function name and body.
 * The function name musts be a 2 characters long string, since all the
 * functions we defined in the Lua context are in the form:
 *
 *   f_<hex sha1 sum>
 *
 * On success REDIS_OK is returned, and nothing is left on the Lua stack.
 * On error REDIS_ERR is returned and an appropriate error is set in the
 * client context. */
int luaCreateFunction(redisClient *c, lua_State *lua, char *funcname, robj *body) {
    sds funcdef = sdsempty();

    funcdef = sdscat(funcdef,"function ");
    funcdef = sdscatlen(funcdef,funcname,42);
    funcdef = sdscatlen(funcdef,"() ",3);
    funcdef = sdscatlen(funcdef,body->ptr,sdslen(body->ptr));
    funcdef = sdscatlen(funcdef," end",4);

    if (luaL_loadbuffer(lua,funcdef,sdslen(funcdef),"@user_script")) {
        addReplyErrorFormat(c,"Error compiling script (new function): %s\n",
            lua_tostring(lua,-1));
        lua_pop(lua,1);
        sdsfree(funcdef);
        return REDIS_ERR;
    }
    sdsfree(funcdef);
    if (lua_pcall(lua,0,0,0)) {
        addReplyErrorFormat(c,"Error running script (new function): %s\n",
            lua_tostring(lua,-1));
        lua_pop(lua,1);
        return REDIS_ERR;
    }

    /* We also save a SHA1 -> Original script map in a dictionary
     * so that we can replicate / write in the AOF all the
     * EVALSHA commands as EVAL using the original script. */
    {
        int retval = dictAdd(server.lua_scripts,
                             sdsnewlen(funcname+2,40),body);
        redisAssertWithInfo(c,NULL,retval == DICT_OK);
        incrRefCount(body);
    }
    return REDIS_OK;
}
Beispiel #8
0
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);
        /* We saved touched key, and protect it, since rpoplpushHandlePush
         * may change the client command argument vector (it does not
         * currently). */
        incrRefCount(touchedkey);
        rpoplpushHandlePush(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,touchedkey);
        signalModifiedKey(c->db,touchedkey);
        decrRefCount(touchedkey);
        server.dirty++;
    }
}
Beispiel #9
0
void spopCommand(redisClient *c) {
    robj *set, *ele, *aux;
    int64_t llele;
    int encoding;

    if ((set = lookupKeyWriteOrReply(c,c->argv[1],shared.nullbulk)) == NULL ||
        checkType(c,set,REDIS_SET)) return;

    encoding = setTypeRandomElement(set,&ele,&llele);
    if (encoding == REDIS_ENCODING_INTSET) {
        ele = createStringObjectFromLongLong(llele);
        set->ptr = intsetRemove(set->ptr,llele,NULL);
    } else {
        incrRefCount(ele);
        setTypeRemove(set,ele);
    }
    notifyKeyspaceEvent(REDIS_NOTIFY_SET,"spop",c->argv[1],c->db->id);

    /* Replicate/AOF this command as an SREM operation */
    aux = createStringObject("SREM",4);
    rewriteClientCommandVector(c,3,aux,c->argv[1],ele);
    decrRefCount(ele);
    decrRefCount(aux);

    addReplyBulk(c,ele);
    if (setTypeSize(set) == 0) {
        dbDelete(c->db,c->argv[1]);
        notifyKeyspaceEvent(REDIS_NOTIFY_GENERIC,"del",c->argv[1],c->db->id);
    }
    signalModifiedKey(c->db,c->argv[1]);
    server.dirty++;
}
Beispiel #10
0
/* Remove the 'key' from the list of blocked keys for a given client.
 *
 * The function returns 1 when there are no longer blocking keys after
 * the current one was removed (and the client can be unblocked). */
int dontWaitForSwappedKey(redisClient *c, robj *key) {
    list *l;
    listNode *ln;
    listIter li;
    struct dictEntry *de;

    /* The key object might be destroyed when deleted from the c->io_keys
     * list (and the "key" argument is physically the same object as the
     * object inside the list), so we need to protect it. */
    incrRefCount(key);

    /* Remove the key from the list of keys this client is waiting for. */
    listRewind(c->io_keys,&li);
    while ((ln = listNext(&li)) != NULL) {
        if (equalStringObjects(ln->value,key)) {
            listDelNode(c->io_keys,ln);
            break;
        }
    }
    redisAssert(ln != NULL);

    /* Remove the client form the key => waiting clients map. */
    de = dictFind(c->db->io_keys,key);
    redisAssert(de != NULL);
    l = dictGetEntryVal(de);
    ln = listSearchKey(l,c);
    redisAssert(ln != NULL);
    listDelNode(l,ln);
    if (listLength(l) == 0)
        dictDelete(c->db->io_keys,key);

    decrRefCount(key);
    return listLength(c->io_keys) == 0;
}
Beispiel #11
0
/* Propagate expires into slaves and the AOF file.
 * When a key expires in the master, a DEL operation for this key is sent
 * to all the slaves and the AOF file if enabled.
 *
 * This way the key expiry is centralized in one place, and since both
 * AOF and the master->slave link guarantee operation ordering, everything
 * will be consistent even if we allow write operations against expiring
 * keys. */
void propagateExpire(redisDb *db, robj *key) {
    robj *argv[2];

    argv[0] = shared.del;
    argv[1] = key;
    incrRefCount(argv[0]);
    incrRefCount(argv[1]);

    if (server.aof_state != REDIS_AOF_OFF)
        feedAppendOnlyFile(server.delCommand,db->id,argv,2);
    if (listLength(server.slaves))
        replicationFeedSlaves(server.slaves,db->id,argv,2);

    decrRefCount(argv[0]);
    decrRefCount(argv[1]);
}
Beispiel #12
0
void listTypeInsert(listTypeEntry *entry, robj *value, int where) {
    robj *subject = entry->li->subject;
    if (entry->li->encoding == REDIS_ENCODING_ZIPLIST) {
        value = getDecodedObject(value);
        if (where == REDIS_TAIL) {
            unsigned char *next = ziplistNext(subject->ptr,entry->zi);

            /* When we insert after the current element, but the current element
             * is the tail of the list, we need to do a push. */
            if (next == NULL) {
                subject->ptr = ziplistPush(subject->ptr,value->ptr,sdslen(value->ptr),REDIS_TAIL);
            } else {
                subject->ptr = ziplistInsert(subject->ptr,next,value->ptr,sdslen(value->ptr));
            }
        } else {
            subject->ptr = ziplistInsert(subject->ptr,entry->zi,value->ptr,sdslen(value->ptr));
        }
        decrRefCount(value);
    } else if (entry->li->encoding == REDIS_ENCODING_LINKEDLIST) {
        if (where == REDIS_TAIL) {
            listInsertNode(subject->ptr,entry->ln,value,AL_START_TAIL);
        } else {
            listInsertNode(subject->ptr,entry->ln,value,AL_START_HEAD);
        }
        incrRefCount(value);
    } else {
        redisPanic("Unknown list encoding");
    }
}
/*	退订模式,即取消客户端对某模式的订阅。如果取消成功返回1,如果客户端并没有订阅该模式则返回0。*/
int pubsubUnsubscribePattern(redisClient *c, robj *pattern, int notify) {
    listNode *ln;
    pubsubPattern pat;
    int retval = 0;

    incrRefCount(pattern); /* Protect the object. May be the same we remove */
    // 遍历c->pubsub_patterns链表,判断该客户端是否订阅了该模式
    if ((ln = listSearchKey(c->pubsub_patterns,pattern)) != NULL) {
    	// 客户端订阅了该模式
        retval = 1;
        // 从c->pubsub_patterns链表中删除该模式
        listDelNode(c->pubsub_patterns,ln);
        pat.client = c;
        pat.pattern = pattern;
        // 从server.pubsub_patterns链表中删除该模式
        ln = listSearchKey(server.pubsub_patterns,&pat);
        listDelNode(server.pubsub_patterns,ln);
    }
    /* Notify the client */
    // 回复客户端
    if (notify) {
        addReply(c,shared.mbulkhdr[3]);
        addReply(c,shared.punsubscribebulk);
        addReplyBulk(c,pattern);
        addReplyLongLong(c,dictSize(c->pubsub_channels)+
                       listLength(c->pubsub_patterns));
    }
    decrRefCount(pattern);
    return retval;
}
Beispiel #14
0
/* Try to encode a string object in order to save space */
robj *tryObjectEncoding(robj *o) {
    long value;
    sds s = o->ptr;
    size_t len;

    if (o->encoding != REDIS_ENCODING_RAW)
        return o; /* Already encoded */

    /* It's not safe to encode shared objects: shared objects can be shared
     * everywhere in the "object space" of Redis. Encoded objects can only
     * appear as "values" (and not, for instance, as keys) */
     if (o->refcount > 1) return o;

    /* Currently we try to encode only strings */
    redisAssertWithInfo(NULL,o,o->type == REDIS_STRING);

    /* Check if we can represent this string as a long integer */
    len = sdslen(s);
    if (len > 21 || !string2l(s,len,&value)) {
        /* We can't encode the object...
         *
         * Do the last try, and at least optimize the SDS string inside
         * the string object to require little space, in case there
         * is more than 10% of free space at the end of the SDS string.
         *
         * We do that for larger strings, using the arbitrary value
         * of 32 bytes. This code was backported from the unstable branch
         * where this is performed when the object is too large to be
         * encoded as EMBSTR. */
        if (len > 32 &&
            o->encoding == REDIS_ENCODING_RAW &&
            sdsavail(s) > len/10)
        {
            o->ptr = sdsRemoveFreeSpace(o->ptr);
        }
        /* Return the original object. */
        return o;
    }

    /* Ok, this object can be encoded...
     *
     * Can I use a shared object? Only if the object is inside a given range
     *
     * Note that we also avoid using shared integers when maxmemory is used
     * because every object needs to have a private LRU field for the LRU
     * algorithm to work well. */
    if (server.maxmemory == 0 && value >= 0 && value < REDIS_SHARED_INTEGERS) {
        decrRefCount(o);
        incrRefCount(shared.integers[value]);
        return shared.integers[value];
    } else {
        o->encoding = REDIS_ENCODING_INT;
        sdsfree(o->ptr);
        o->ptr = (void*) value;
        return o;
    }
}
Beispiel #15
0
int vmSwapObjectThreaded(robj *key, robj *val, redisDb *db) {
    iojob *j;

    j = zmalloc(sizeof(*j));
    j->type = REDIS_IOJOB_PREPARE_SWAP;
    j->db = db;
    j->key = key;
    incrRefCount(key);
    j->id = j->val = val;
    incrRefCount(val);
    j->canceled = 0;
    j->thread = (pthread_t) -1;
    val->storage = REDIS_VM_SWAPPING;

    lockThreadedIO();
    queueIOJob(j);
    unlockThreadedIO();
    return REDIS_OK;
}
Beispiel #16
0
/* High level Set operation. This function can be used in order to set
 * a key, whatever it was existing or not, to a new object.
 *
 * 1) The ref count of the value object is incremented.
 * 2) clients WATCHing for the destination key notified.
 * 3) The expire time of the key is reset (the key is made persistent). */
void setKey(redisDb *db, robj *key, robj *val) {
    if (lookupKeyWrite(db,key) == NULL) {
        dbAdd(db,key,val);
    } else {
        dbOverwrite(db,key,val);
    }
    incrRefCount(val);
    removeExpire(db,key);
    signalModifiedKey(db,key);
}
Beispiel #17
0
/* Set a client in blocking mode for the specified key (list or stream), with
 * the specified timeout. The 'type' argument is BLOCKED_LIST or BLOCKED_STREAM
 * depending on the kind of operation we are waiting for an empty key in
 * order to awake the client. The client is blocked for all the 'numkeys'
 * keys as in the 'keys' argument. When we block for stream keys, we also
 * provide an array of streamID structures: clients will be unblocked only
 * when items with an ID greater or equal to the specified one is appended
 * to the stream. */
void blockForKeys(client *c, int btype, robj **keys, int numkeys, mstime_t timeout, robj *target, streamID *ids) {
    dictEntry *de;
    list *l;
    int j;

    c->bpop.timeout = timeout;
    c->bpop.target = target;

    if (target != NULL) incrRefCount(target);

    for (j = 0; j < numkeys; j++) {
        /* The value associated with the key name in the bpop.keys dictionary
         * is NULL for lists, or the stream ID for streams. */
        void *key_data = NULL;
        if (btype == BLOCKED_STREAM) {
            key_data = zmalloc(sizeof(streamID));
            memcpy(key_data,ids+j,sizeof(streamID));
        }

        /* If the key already exists in the dictionary ignore it. */
        if (dictAdd(c->bpop.keys,keys[j],key_data) != DICT_OK) {
            zfree(key_data);
            continue;
        }
        incrRefCount(keys[j]);

        /* And in the other "side", to map keys -> clients */
        de = dictFind(c->db->blocking_keys,keys[j]);
        if (de == NULL) {
            int retval;

            /* For every key we take a list of clients blocked for it */
            l = listCreate();
            retval = dictAdd(c->db->blocking_keys,keys[j],l);
            incrRefCount(keys[j]);
            serverAssertWithInfo(c,keys[j],retval == DICT_OK);
        } else {
            l = dictGetVal(de);
        }
        listAddNodeTail(l,c);
    }
    blockClient(c,btype);
}
void incrRefCount_Array(Array array, MemoryIncrementer incrementer){
    incrRefCount(array.memory);
    
    if(incrementer != NULL){
        unsigned i=0;
        for(; i < array.length; ++i){
            incrementer(getItemPointer(&array, i));    
        }
    }
}
Beispiel #19
0
/* Try to share an object against the shared objects pool */
static robj *tryObjectSharing(robj *o) {
    struct dictEntry *de;
    unsigned long c;

    if (o == NULL || server.shareobjects == 0) return o;

    de = dictFind(server.sharingpool,o);
    if (de) {
        robj *shared = dictGetEntryKey(de);

        c = ((unsigned long) dictGetEntryVal(de))+1;
        dictGetEntryVal(de) = (void*) c;
        incrRefCount(shared);
        decrRefCount(o);
        return shared;
    } else {
        /* Here we are using a stream algorihtm: Every time an object is
         * shared we increment its count, everytime there is a miss we
         * recrement the counter of a random object. If this object reaches
         * zero we remove the object and put the current object instead. */
        if (dictSize(server.sharingpool) >=
                server.sharingpoolsize) {
            de = dictGetRandomKey(server.sharingpool);
            
            c = ((unsigned long) dictGetEntryVal(de))-1;
            dictGetEntryVal(de) = (void*) c;
            if (c == 0) {
                dictDelete(server.sharingpool,de->key);
            }
        } else {
            c = 0; /* If the pool is empty we want to add this object */
        }
        if (c == 0) {
            int retval;

            retval = dictAdd(server.sharingpool,o,(void*)1);
            redisAssert(retval == DICT_OK);
            incrRefCount(o);
        }
        return o;
    }
}
// keys是一个key的数组,个数为numkeys个
// timeout保存超时时间
// target保存解除阻塞时的key对象,用于BRPOPLPUSH函数
// 根据给定的key将client阻塞
void blockForKeys(client *c, robj **keys, int numkeys, mstime_t timeout, robj *target) {
    dictEntry *de;
    list *l;
    int j;

    //设置超时时间和target
    c->bpop.timeout = timeout;
    c->bpop.target = target;

    //增加target的引用计数
    if (target != NULL) incrRefCount(target);

    //将当前client的numkeys个key设置为阻塞
    for (j = 0; j < numkeys; j++) {
        /* If the key already exists in the dict ignore it. */
        //bpop.keys记录所有造成client阻塞的键
        //将要阻塞的键放入bpop.keys字典中
        if (dictAdd(c->bpop.keys,keys[j],NULL) != DICT_OK) continue;
        //当前的key引用计数加1
        incrRefCount(keys[j]);

        /* And in the other "side", to map keys -> clients */
        //db->blocking_keys是一个字典,字典的键为bpop.keys中的一个键,值是一个列表,保存着所有被该键阻塞的client
        //当前造成client被阻塞的键有没有当前的key
        de = dictFind(c->db->blocking_keys,keys[j]);
        if (de == NULL) {   //没有当前的key,添加进去
            int retval;

            /* For every key we take a list of clients blocked for it */
            //创建一个列表
            l = listCreate();
            //将造成阻塞的键和列表添加到db->blocking_keys字典中
            retval = dictAdd(c->db->blocking_keys,keys[j],l);
            incrRefCount(keys[j]);
            serverAssertWithInfo(c,keys[j],retval == DICT_OK);
        } else {    //如果已经有了,则当前key的值保存起来,值是一个列表
            l = dictGetVal(de);
        }
        listAddNodeTail(l,c);   //将当前client加入到阻塞的client的列表
    }
    blockClient(c,BLOCKED_LIST);    //阻塞client
}
Beispiel #21
0
/*
 * 监视给定 key
 *
 * T = O(N)
 */
void watchForKey(redisClient *c, robj *key)
{
    list *clients = NULL;
    listIter li;
    listNode *ln;
    watchedKey *wk;

    /* Check if we are already watching for this key */
    // 检查该 key 是否已经被 WATCH
    // (出现在 WATCH 命令调用时一个 key 被输入多次的情况)
    // 如果是的话,直接返回
    // O(N)
    listRewind(c->watched_keys,&li);
    while((ln = listNext(&li)))
    {
        wk = listNodeValue(ln);
        if (wk->db == c->db && equalStringObjects(key,wk->key))
            return; /* Key already watched */
    }

    // key 未被监视
    // 根据 key ,将客户端加入到 DB 的监视 key 字典中
    /* This key is not already watched in this DB. Let's add it */
    // O(1)
    clients = dictFetchValue(c->db->watched_keys,key);
    if (!clients)
    {
        clients = listCreate();
        dictAdd(c->db->watched_keys,key,clients);
        incrRefCount(key);
    }
    listAddNodeTail(clients,c);

    // 将 key 添加到客户端的监视列表中
    /* Add the new key to the lits of keys watched by this client */
    // O(1)
    wk = zmalloc(sizeof(*wk));
    wk->key = key;
    wk->db = c->db;
    incrRefCount(key);
    listAddNodeTail(c->watched_keys,wk);
}
Beispiel #22
0
void movekeysCommand(redisClient *c) {
    redisDb *src, *dst;
    int srcid;

    dictIterator *di;
    dictEntry *de;
    sds pattern = c->argv[1]->ptr;
    int plen = sdslen(pattern), allkeys;
    unsigned long numkeys = 0;

    /* Obtain source and target DB pointers */
    src = c->db;
    srcid = c->db->id;
    if (selectDb(c,atoi(c->argv[2]->ptr)) == REDIS_ERR) {
        addReply(c,shared.outofrangeerr);
        return;
    }
    dst = c->db;
    selectDb(c,srcid); /* Back to the source DB */

    /* If the user is moving using as target the same
     * DB as the source DB it is probably an error. */
    if (src == dst) {
        addReply(c,shared.sameobjecterr);
        return;
    }

    di = dictGetIterator(c->db->dict);
    allkeys = (pattern[0] == '*' && pattern[1] == '\0');
    while((de = dictNext(di)) != NULL) {
        sds key = dictGetEntryKey(de);
        robj *keyobj;

        if (allkeys || stringmatchlen(pattern,plen,key,sdslen(key),0)) {
            keyobj = createStringObject(key,sdslen(key));
            if (expireIfNeeded(c->db,keyobj) == 0) {
                robj *val = dictGetEntryVal(de);

                /* Try to add the element to the target DB */
                if (dbAdd(dst,keyobj,val) != REDIS_ERR) {
                    incrRefCount(val);

                    /* OK! key moved, free the entry in the source DB */
                    dbDelete(src,keyobj);
                    server.dirty++;
                    numkeys++;
                }
            }
            decrRefCount(keyobj);
        }
    }
    dictReleaseIterator(di);
    addReplyLongLong(c,numkeys);
}
Beispiel #23
0
void moveCommand(client *c) {
    robj *o;
    redisDb *src, *dst;
    int srcid;
    long long dbid, expire;

    if (server.cluster_enabled) {
        addReplyError(c,"MOVE is not allowed in cluster mode");
        return;
    }

    /* Obtain source and target DB pointers */
    src = c->db;
    srcid = c->db->id;

    if (getLongLongFromObject(c->argv[2],&dbid) == C_ERR ||
        dbid < INT_MIN || dbid > INT_MAX ||
        selectDb(c,dbid) == C_ERR)
    {
        addReply(c,shared.outofrangeerr);
        return;
    }
    dst = c->db;
    selectDb(c,srcid); /* Back to the source DB */

    /* If the user is moving using as target the same
     * DB as the source DB it is probably an error. */
    if (src == dst) {
        addReply(c,shared.sameobjecterr);
        return;
    }

    /* Check if the element exists and get a reference */
    o = lookupKeyWrite(c->db,c->argv[1]);
    if (!o) {
        addReply(c,shared.czero);
        return;
    }
    expire = getExpire(c->db,c->argv[1]);

    /* Return zero if the key already exists in the target DB */
    if (lookupKeyWrite(dst,c->argv[1]) != NULL) {
        addReply(c,shared.czero);
        return;
    }
    dbAdd(dst,c->argv[1],o);
    if (expire != -1) setExpire(dst,c->argv[1],expire);
    incrRefCount(o);

    /* OK! key moved, free the entry in the source DB */
    dbDelete(src,c->argv[1]);
    server.dirty++;
    addReply(c,shared.cone);
}
Beispiel #24
0
/* This should be called from any function PUSHing into lists.
 * 'c' is the "pushing client", 'key' is the key it is pushing data against,
 * 'ele' is the element pushed.
 *
 * If the function returns 0 there was no client waiting for a list push
 * against this key.
 *
 * If the function returns 1 there was a client waiting for a list push
 * against this key, the element was passed to this client thus it's not
 * needed to actually add it to the list and the caller should return asap. */
int handleClientsWaitingListPush(redisClient *c, robj *key, robj *ele) {
    struct dictEntry *de;
    redisClient *receiver;
    int numclients;
    list *clients;
    listNode *ln;
    robj *dstkey, *dstobj;

    de = dictFind(c->db->blocking_keys,key);
    if (de == NULL) return 0;
    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;
}
Beispiel #25
0
void hgetCommand(caller_t *c)
{
        int ret;
        robj *o;
        robj *field = c->argv[2];
        robj *result;

        if ((o = lookupKeyRead(c->db,c->argv[1])) == NULL) {
                caller_set_err(c, ERR_NIL);
                return;
        }

        if (o->type != REDIS_HASH) {
                caller_set_err(c, ERR_TYPE);
                return;
        }

        if (o->encoding == REDIS_ENCODING_ZIPLIST) {
                unsigned char *vstr = NULL;
                unsigned int vlen = UINT_MAX;
                long long vll = LLONG_MAX;

                ret = hashTypeGetFromZiplist(o,field,&vstr,&vlen,&vll);
                if (ret < 0) {
                        caller_set_err(c, ERR_NIL);
                        return;
                } else {
                        if (vstr) {
                                result = createObject(REDIS_STRING, sdsnewlen(vstr, vlen));
                                caller_add_result(c, result);
                                return;
                        } else {
                                result = createObject(REDIS_STRING, (void*)vll);
                                result->encoding = REDIS_ENCODING_INT;
                                caller_add_result(c, result);
                                return;
                        }
                }

        } else if (o->encoding == REDIS_ENCODING_HT) {
                ret = hashTypeGetFromHashTable(o,field,&result);
                if (ret < 0) {
                        caller_set_err(c, ERR_NIL);
                        return;
                } else {
                        caller_add_result(c, result);
                        incrRefCount(result);
                        return;
                }
        } else {
                logicError("Unknown hash encoding");
        }
}
Beispiel #26
0
void setGenericCommand(redisClient *c, int nx, robj *key, robj *val, robj *expire) {
    int retval;
    long seconds = 0; /* initialized to avoid an harmness warning */

#ifdef AUTH_FEATURE
    /* Check mod permissions */
    if (authCheckModOrReply(c) == REDIS_ERR)
      return;
    /* Check permissions */
    if (authCheckPathOrReply(c, key) == REDIS_ERR)
      return;
#endif

    if (expire) {
        if (getLongFromObjectOrReply(c, expire, &seconds, NULL) != REDIS_OK)
            return;
        if (seconds <= 0) {
            addReplyError(c,"invalid expire time in SETEX");
            return;
        }
    }

    retval = dbAdd(c->db,key,val);
    if (retval == REDIS_ERR) {
        if (!nx) {
            dbReplace(c->db,key,val);
            incrRefCount(val);
        } else {
            addReply(c,shared.czero);
            return;
        }
    } else {
        incrRefCount(val);
    }
    touchWatchedKey(c->db,key);
    server.dirty++;
    removeExpire(c->db,key);
    if (expire) setExpire(c->db,key,time(NULL)+seconds);
    addReply(c, nx ? shared.cone : shared.ok);
}
Beispiel #27
0
/* If the specified key has clients blocked waiting for list pushes, this
 * function will put the key reference into the server.ready_keys list.
 * Note that db->ready_keys is a hash table that allows us to avoid putting
 * the same key again and again in the list in case of multiple pushes
 * made by a script or in the context of MULTI/EXEC.
 *
 * The list will be finally processed by handleClientsBlockedOnLists() */
void signalListAsReady(redisDb *db, robj *key) {
    readyList *rl;

    /* No clients blocking for this key? No need to queue it. */
    if (dictFind(db->blocking_keys,key) == NULL) return;

    /* Key was already signaled? No need to queue it again. */
    if (dictFind(db->ready_keys,key) != NULL) return;

    /* Ok, we need to queue this key into server.ready_keys. */
    rl = zmalloc(sizeof(*rl));
    rl->key = key;
    rl->db = db;
    incrRefCount(key);
    listAddNodeTail(server.ready_keys,rl);

    /* We also add the key in the db->ready_keys dictionary in order
     * to avoid adding it multiple times into a list with a simple O(1)
     * check. */
    incrRefCount(key);
    redisAssert(dictAdd(db->ready_keys,key,NULL) == DICT_OK);
}
// WATCH 某个 KEY
void watchForKey(redisClient *c, robj *key) {
    list *clients = NULL;
    listIter li;
    listNode *ln;
    watchedKey *wk;

    /* Check if we are already watching for this key */
    // 所有被 WATCHED 的 KEY 都被放在 redisClient.watched_keys 链表中
    // 遍历这个链表,查看这个 KEY 是否已经处于监视状态(WATCHED)
    listRewind(c->watched_keys,&li);
    while((ln = listNext(&li))) {
        wk = listNodeValue(ln);
        if (wk->db == c->db && equalStringObjects(key,wk->key))
            return; /* Key already watched */
    }

    /* This key is not already watched in this DB. Let's add it */
    // 如果 KEY 还没有被 WATCH 过,那么对它进行 WATCH
    clients = dictFetchValue(c->db->watched_keys,key);
    if (!clients) { 
        // 如果 clients 链表不存在
        // 说明这个客户端是第一个监视这个 DB 的这个 KEY 的客户端
        // 那么 clients 创建链表,并将它添加到 c->db->watched_keys 字典中
        clients = listCreate();
        dictAdd(c->db->watched_keys,key,clients);
        incrRefCount(key);
    }
    // 将客户端添加到 clients 链表
    listAddNodeTail(clients,c); 

    /* Add the new key to the lits of keys watched by this client */
    // 除了 c->db->watched_keys 之外
    // 还要将被 WATCH 的 KEY 添加到 c->watched_keys
    wk = zmalloc(sizeof(*wk));
    wk->key = key;
    wk->db = c->db;
    incrRefCount(key);
    listAddNodeTail(c->watched_keys,wk);
}
Beispiel #29
0
/* Define a lua function with the specified function name and body.
 *
 * 根据给定函数名和代码体(body),创建 Lua 函数。
 *
 * The function name musts be a 2 characters long string, since all the
 * functions we defined in the Lua context are in the form:
 *
 * 所有函数名称的长度都必须大于 2 ,因为我们使用以下格式来创建函数名:
 *
 *   f_<hex sha1 sum>
 *
 * On success REDIS_OK is returned, and nothing is left on the Lua stack.
 * 创建成功返回 REDIS_OK ,并清除 Lua 栈中的所有资料。
 *
 * On error REDIS_ERR is returned and an appropriate error is set in the
 * client context.
 */
int luaCreateFunction(redisClient *c, lua_State *lua, char *funcname, robj *body)
{
    sds funcdef = sdsempty();

    // 函数定义
    funcdef = sdscat(funcdef,"function ");
    funcdef = sdscatlen(funcdef,funcname,42);
    funcdef = sdscatlen(funcdef,"() ",3);
    funcdef = sdscatlen(funcdef,body->ptr,sdslen(body->ptr));
    funcdef = sdscatlen(funcdef," end",4);

    // 将函数定义载入到 Lua 中(并编译),但不执行该定义
    if (luaL_loadbuffer(lua,funcdef,sdslen(funcdef),"@user_script"))
    {

        // 如果编译出错,那么返回错误
        addReplyErrorFormat(c,"Error compiling script (new function): %s\n",
                            lua_tostring(lua,-1));
        lua_pop(lua,1);
        sdsfree(funcdef);
        return REDIS_ERR;
    }
    sdsfree(funcdef);

    // 定义函数
    if (lua_pcall(lua,0,0,0))
    {
        addReplyErrorFormat(c,"Error running script (new function): %s\n",
                            lua_tostring(lua,-1));
        lua_pop(lua,1);
        return REDIS_ERR;
    }

    /* We also save a SHA1 -> Original script map in a dictionary
     * so that we can replicate / write in the AOF all the
     * EVALSHA commands as EVAL using the original script.
     *
     * 创建一个从 SHA1 映射到原始脚本的字典,
     * 从而使得脚本可以用于复制,以及写入到 AOF 文件
     */
    {
        int retval = dictAdd(server.lua_scripts,
                             // SHA1 值,不包括前缀 f_
                             sdsnewlen(funcname+2,40),
                             // 代码体
                             body);
        redisAssertWithInfo(c,NULL,retval == DICT_OK);
        incrRefCount(body);
    }
    return REDIS_OK;
}
Beispiel #30
0
void spopCommand(redisClient *c) {
    robj *set, *ele, *aux;
    int64_t llele;
    int encoding;

    if (c->argc == 3) {
        spopWithCountCommand(c);
        return;
    } else if (c->argc > 3) {
        addReply(c,shared.syntaxerr);
        return;
    }

    /* Make sure a key with the name inputted exists, and that it's type is
     * indeed a set */
    if ((set = lookupKeyWriteOrReply(c,c->argv[1],shared.nullbulk)) == NULL ||
        checkType(c,set,REDIS_SET)) return;

    /* Get a random element from the set */
    encoding = setTypeRandomElement(set,&ele,&llele);

    /* Remove the element from the set */
    if (encoding == REDIS_ENCODING_INTSET) {
        ele = createStringObjectFromLongLong(llele);
        set->ptr = intsetRemove(set->ptr,llele,NULL);
    } else {
        incrRefCount(ele);
        setTypeRemove(set,ele);
    }

    notifyKeyspaceEvent(REDIS_NOTIFY_SET,"spop",c->argv[1],c->db->id);

    /* Replicate/AOF this command as an SREM operation */
    aux = createStringObject("SREM",4);
    rewriteClientCommandVector(c,3,aux,c->argv[1],ele);
    decrRefCount(ele);
    decrRefCount(aux);

    /* Add the element to the reply */
    addReplyBulk(c,ele);

    /* Delete the set if it's empty */
    if (setTypeSize(set) == 0) {
        dbDelete(c->db,c->argv[1]);
        notifyKeyspaceEvent(REDIS_NOTIFY_GENERIC,"del",c->argv[1],c->db->id);
    }

    /* Set has been modified */
    signalModifiedKey(c->db,c->argv[1]);
    server.dirty++;
}