]> git.saurik.com Git - redis.git/blobdiff - redis.c
Remove trailing whitespace.
[redis.git] / redis.c
diff --git a/redis.c b/redis.c
index 8faa1edb4ac221e8306bdb78b52eb2b45295cfbf..e83a6269db7cf765a4785d71ee889e49f3ad85fc 100644 (file)
--- a/redis.c
+++ b/redis.c
@@ -27,7 +27,7 @@
  * POSSIBILITY OF SUCH DAMAGE.
  */
 
-#define REDIS_VERSION "1.3.4"
+#define REDIS_VERSION "1.3.8"
 
 #include "fmacros.h"
 #include "config.h"
 #define REDIS_MAXIDLETIME       (60*5)  /* default client timeout */
 #define REDIS_IOBUF_LEN         1024
 #define REDIS_LOADBUF_LEN       1024
-#define REDIS_STATIC_ARGS       4
+#define REDIS_STATIC_ARGS       8
 #define REDIS_DEFAULT_DBNUM     16
 #define REDIS_CONFIGLINE_MAX    1024
 #define REDIS_OBJFREELIST_MAX   1000000 /* Max number of objects to cache */
 #define REDIS_MAX_SYNC_TIME     60      /* Slave can't take more to sync */
-#define REDIS_EXPIRELOOKUPS_PER_CRON    100 /* try to expire 100 keys/second */
+#define REDIS_EXPIRELOOKUPS_PER_CRON    10 /* try to expire 10 keys/loop */
 #define REDIS_MAX_WRITE_PER_EVENT (1024*64)
 #define REDIS_REQUEST_MAX_SIZE (1024*1024*256) /* max bytes in inline command */
 
    config file and the server is using more than maxmemory bytes of memory.
    In short this commands are denied on low memory conditions. */
 #define REDIS_CMD_DENYOOM       4
+#define REDIS_CMD_FORCE_REPLICATION 8 /* Force replication even if dirty is 0 */
 
 /* Object types */
 #define REDIS_STRING 0
@@ -327,6 +328,8 @@ typedef struct redisClient {
                              * is >= blockingto then the operation timed out. */
     list *io_keys;          /* Keys this client is waiting to be loaded from the
                              * swap file in order to continue. */
+    dict *pubsub_channels;  /* channels a client is interested in (SUBSCRIBE) */
+    list *pubsub_patterns;  /* patterns a client is interested in (SUBSCRIBE) */
 } redisClient;
 
 struct saveparam {
@@ -339,8 +342,6 @@ struct redisServer {
     int port;
     int fd;
     redisDb *db;
-    dict *sharingpool;          /* Poll used for object sharing */
-    unsigned int sharingpoolsize;
     long long dirty;            /* changes to DB from the last save */
     list *clients;
     list *slaves, *monitors;
@@ -353,6 +354,7 @@ struct redisServer {
     time_t stat_starttime;         /* server start time */
     long long stat_numcommands;    /* number of processed commands */
     long long stat_numconnections; /* number of connections received */
+    long long stat_expiredkeys;   /* number of expired keys */
     /* Configuration */
     int verbosity;
     int glueoutputbuf;
@@ -434,15 +436,28 @@ struct redisServer {
     unsigned long long vm_stats_swapped_objects;
     unsigned long long vm_stats_swapouts;
     unsigned long long vm_stats_swapins;
+    /* Pubsub */
+    dict *pubsub_channels; /* Map channels to list of subscribed clients */
+    list *pubsub_patterns; /* A list of pubsub_patterns */
+    /* Misc */
     FILE *devnull;
 };
 
+typedef struct pubsubPattern {
+    redisClient *client;
+    robj *pattern;
+} pubsubPattern;
+
 typedef void redisCommandProc(redisClient *c);
 struct redisCommand {
     char *name;
     redisCommandProc *proc;
     int arity;
     int flags;
+    /* Use a function to determine which keys need to be loaded
+     * in the background prior to executing this command. Takes precedence
+     * over vm_firstkey and others, ignored when NULL */
+    redisCommandProc *vm_preload_proc;
     /* What keys should be loaded in background when calling this command? */
     int vm_firstkey; /* The first argument that's a key (0 = no keys) */
     int vm_lastkey;  /* THe last argument that's a key */
@@ -490,13 +505,16 @@ typedef struct zset {
 
 /* Our shared "common" objects */
 
+#define REDIS_SHARED_INTEGERS 10000
 struct sharedObjectsStruct {
     robj *crlf, *ok, *err, *emptybulk, *czero, *cone, *pong, *space,
     *colon, *nullbulk, *nullmultibulk, *queued,
     *emptymultibulk, *wrongtypeerr, *nokeyerr, *syntaxerr, *sameobjecterr,
     *outofrangeerr, *plus,
     *select0, *select1, *select2, *select3, *select4,
-    *select5, *select6, *select7, *select8, *select9;
+    *select5, *select6, *select7, *select8, *select9,
+    *messagebulk, *subscribebulk, *unsubscribebulk, *mbulk3,
+    *psubscribebulk, *punsubscribebulk, *integers[REDIS_SHARED_INTEGERS];
 } shared;
 
 /* Global vars that are actally used as constants. The following double
@@ -516,7 +534,7 @@ typedef struct iojob {
     robj *val;  /* the value to swap for REDIS_IOREQ_*_SWAP, otherwise this
                  * field is populated by the I/O thread for REDIS_IOREQ_LOAD. */
     off_t page; /* Swap page where to read/write the object */
-    off_t pages; /* Swap pages needed to safe object. PREPARE_SWAP return val */
+    off_t pages; /* Swap pages needed to save object. PREPARE_SWAP return val */
     int canceled; /* True if this command was canceled by blocking side of VM */
     pthread_t thread; /* ID of the thread processing this entry */
 } iojob;
@@ -536,11 +554,10 @@ static void incrRefCount(robj *o);
 static int rdbSaveBackground(char *filename);
 static robj *createStringObject(char *ptr, size_t len);
 static robj *dupStringObject(robj *o);
-static void replicationFeedSlaves(list *slaves, struct redisCommand *cmd, int dictid, robj **argv, int argc);
+static void replicationFeedSlaves(list *slaves, int dictid, robj **argv, int argc);
 static void feedAppendOnlyFile(struct redisCommand *cmd, int dictid, robj **argv, int argc);
 static int syncWithMaster(void);
-static robj *tryObjectSharing(robj *o);
-static int tryObjectEncoding(robj *o);
+static robj *tryObjectEncoding(robj *o);
 static robj *getDecodedObject(robj *o);
 static int removeExpire(redisDb *db, robj *key);
 static int expireIfNeeded(redisDb *db, robj *key);
@@ -587,6 +604,7 @@ static robj *vmReadObjectFromSwap(off_t page, int type);
 static void waitEmptyIOJobsQueue(void);
 static void vmReopenSwapFile(void);
 static int vmFreePage(off_t page);
+static void zunionInterBlockClientOnSwappedKeys(redisClient *c);
 static int blockClientOnSwappedKeys(struct redisCommand *cmd, redisClient *c);
 static int dontWaitForSwappedKey(redisClient *c, robj *key);
 static void handleClientsBlockedOnSwappedKey(redisDb *db, robj *key);
@@ -595,6 +613,12 @@ static struct redisCommand *lookupCommand(char *name);
 static void call(redisClient *c, struct redisCommand *cmd);
 static void resetClient(redisClient *c);
 static void convertToRealHash(robj *o);
+static int pubsubUnsubscribeAllChannels(redisClient *c, int notify);
+static int pubsubUnsubscribeAllPatterns(redisClient *c, int notify);
+static void freePubsubPattern(void *p);
+static int listMatchPubsubPattern(void *a, void *b);
+static int compareStringObjects(robj *a, robj *b);
+static void usage();
 
 static void authCommand(redisClient *c);
 static void pingCommand(redisClient *c);
@@ -680,6 +704,7 @@ static void substrCommand(redisClient *c);
 static void zrankCommand(redisClient *c);
 static void zrevrankCommand(redisClient *c);
 static void hsetCommand(redisClient *c);
+static void hmsetCommand(redisClient *c);
 static void hgetCommand(redisClient *c);
 static void hdelCommand(redisClient *c);
 static void hlenCommand(redisClient *c);
@@ -690,114 +715,129 @@ static void hkeysCommand(redisClient *c);
 static void hvalsCommand(redisClient *c);
 static void hgetallCommand(redisClient *c);
 static void hexistsCommand(redisClient *c);
+static void configCommand(redisClient *c);
+static void hincrbyCommand(redisClient *c);
+static void subscribeCommand(redisClient *c);
+static void unsubscribeCommand(redisClient *c);
+static void psubscribeCommand(redisClient *c);
+static void punsubscribeCommand(redisClient *c);
+static void publishCommand(redisClient *c);
 
 /*================================= Globals ================================= */
 
 /* Global vars */
 static struct redisServer server; /* server global state */
 static struct redisCommand cmdTable[] = {
-    {"get",getCommand,2,REDIS_CMD_INLINE,1,1,1},
-    {"set",setCommand,3,REDIS_CMD_BULK|REDIS_CMD_DENYOOM,0,0,0},
-    {"setnx",setnxCommand,3,REDIS_CMD_BULK|REDIS_CMD_DENYOOM,0,0,0},
-    {"append",appendCommand,3,REDIS_CMD_BULK|REDIS_CMD_DENYOOM,1,1,1},
-    {"substr",substrCommand,4,REDIS_CMD_INLINE,1,1,1},
-    {"del",delCommand,-2,REDIS_CMD_INLINE,0,0,0},
-    {"exists",existsCommand,2,REDIS_CMD_INLINE,1,1,1},
-    {"incr",incrCommand,2,REDIS_CMD_INLINE|REDIS_CMD_DENYOOM,1,1,1},
-    {"decr",decrCommand,2,REDIS_CMD_INLINE|REDIS_CMD_DENYOOM,1,1,1},
-    {"mget",mgetCommand,-2,REDIS_CMD_INLINE,1,-1,1},
-    {"rpush",rpushCommand,3,REDIS_CMD_BULK|REDIS_CMD_DENYOOM,1,1,1},
-    {"lpush",lpushCommand,3,REDIS_CMD_BULK|REDIS_CMD_DENYOOM,1,1,1},
-    {"rpop",rpopCommand,2,REDIS_CMD_INLINE,1,1,1},
-    {"lpop",lpopCommand,2,REDIS_CMD_INLINE,1,1,1},
-    {"brpop",brpopCommand,-3,REDIS_CMD_INLINE,1,1,1},
-    {"blpop",blpopCommand,-3,REDIS_CMD_INLINE,1,1,1},
-    {"llen",llenCommand,2,REDIS_CMD_INLINE,1,1,1},
-    {"lindex",lindexCommand,3,REDIS_CMD_INLINE,1,1,1},
-    {"lset",lsetCommand,4,REDIS_CMD_BULK|REDIS_CMD_DENYOOM,1,1,1},
-    {"lrange",lrangeCommand,4,REDIS_CMD_INLINE,1,1,1},
-    {"ltrim",ltrimCommand,4,REDIS_CMD_INLINE,1,1,1},
-    {"lrem",lremCommand,4,REDIS_CMD_BULK,1,1,1},
-    {"rpoplpush",rpoplpushcommand,3,REDIS_CMD_INLINE|REDIS_CMD_DENYOOM,1,2,1},
-    {"sadd",saddCommand,3,REDIS_CMD_BULK|REDIS_CMD_DENYOOM,1,1,1},
-    {"srem",sremCommand,3,REDIS_CMD_BULK,1,1,1},
-    {"smove",smoveCommand,4,REDIS_CMD_BULK,1,2,1},
-    {"sismember",sismemberCommand,3,REDIS_CMD_BULK,1,1,1},
-    {"scard",scardCommand,2,REDIS_CMD_INLINE,1,1,1},
-    {"spop",spopCommand,2,REDIS_CMD_INLINE,1,1,1},
-    {"srandmember",srandmemberCommand,2,REDIS_CMD_INLINE,1,1,1},
-    {"sinter",sinterCommand,-2,REDIS_CMD_INLINE|REDIS_CMD_DENYOOM,1,-1,1},
-    {"sinterstore",sinterstoreCommand,-3,REDIS_CMD_INLINE|REDIS_CMD_DENYOOM,2,-1,1},
-    {"sunion",sunionCommand,-2,REDIS_CMD_INLINE|REDIS_CMD_DENYOOM,1,-1,1},
-    {"sunionstore",sunionstoreCommand,-3,REDIS_CMD_INLINE|REDIS_CMD_DENYOOM,2,-1,1},
-    {"sdiff",sdiffCommand,-2,REDIS_CMD_INLINE|REDIS_CMD_DENYOOM,1,-1,1},
-    {"sdiffstore",sdiffstoreCommand,-3,REDIS_CMD_INLINE|REDIS_CMD_DENYOOM,2,-1,1},
-    {"smembers",sinterCommand,2,REDIS_CMD_INLINE,1,1,1},
-    {"zadd",zaddCommand,4,REDIS_CMD_BULK|REDIS_CMD_DENYOOM,1,1,1},
-    {"zincrby",zincrbyCommand,4,REDIS_CMD_BULK|REDIS_CMD_DENYOOM,1,1,1},
-    {"zrem",zremCommand,3,REDIS_CMD_BULK,1,1,1},
-    {"zremrangebyscore",zremrangebyscoreCommand,4,REDIS_CMD_INLINE,1,1,1},
-    {"zremrangebyrank",zremrangebyrankCommand,4,REDIS_CMD_INLINE,1,1,1},
-    {"zunion",zunionCommand,-4,REDIS_CMD_INLINE|REDIS_CMD_DENYOOM,0,0,0},
-    {"zinter",zinterCommand,-4,REDIS_CMD_INLINE|REDIS_CMD_DENYOOM,0,0,0},
-    {"zrange",zrangeCommand,-4,REDIS_CMD_INLINE,1,1,1},
-    {"zrangebyscore",zrangebyscoreCommand,-4,REDIS_CMD_INLINE,1,1,1},
-    {"zcount",zcountCommand,4,REDIS_CMD_INLINE,1,1,1},
-    {"zrevrange",zrevrangeCommand,-4,REDIS_CMD_INLINE,1,1,1},
-    {"zcard",zcardCommand,2,REDIS_CMD_INLINE,1,1,1},
-    {"zscore",zscoreCommand,3,REDIS_CMD_BULK|REDIS_CMD_DENYOOM,1,1,1},
-    {"zrank",zrankCommand,3,REDIS_CMD_BULK,1,1,1},
-    {"zrevrank",zrevrankCommand,3,REDIS_CMD_BULK,1,1,1},
-    {"hset",hsetCommand,4,REDIS_CMD_BULK|REDIS_CMD_DENYOOM,1,1,1},
-    {"hget",hgetCommand,3,REDIS_CMD_BULK,1,1,1},
-    {"hdel",hdelCommand,3,REDIS_CMD_BULK,1,1,1},
-    {"hlen",hlenCommand,2,REDIS_CMD_INLINE,1,1,1},
-    {"hkeys",hkeysCommand,2,REDIS_CMD_INLINE,1,1,1},
-    {"hvals",hvalsCommand,2,REDIS_CMD_INLINE,1,1,1},
-    {"hgetall",hgetallCommand,2,REDIS_CMD_INLINE,1,1,1},
-    {"hexists",hexistsCommand,3,REDIS_CMD_BULK,1,1,1},
-    {"incrby",incrbyCommand,3,REDIS_CMD_INLINE|REDIS_CMD_DENYOOM,1,1,1},
-    {"decrby",decrbyCommand,3,REDIS_CMD_INLINE|REDIS_CMD_DENYOOM,1,1,1},
-    {"getset",getsetCommand,3,REDIS_CMD_BULK|REDIS_CMD_DENYOOM,1,1,1},
-    {"mset",msetCommand,-3,REDIS_CMD_BULK|REDIS_CMD_DENYOOM,1,-1,2},
-    {"msetnx",msetnxCommand,-3,REDIS_CMD_BULK|REDIS_CMD_DENYOOM,1,-1,2},
-    {"randomkey",randomkeyCommand,1,REDIS_CMD_INLINE,0,0,0},
-    {"select",selectCommand,2,REDIS_CMD_INLINE,0,0,0},
-    {"move",moveCommand,3,REDIS_CMD_INLINE,1,1,1},
-    {"rename",renameCommand,3,REDIS_CMD_INLINE,1,1,1},
-    {"renamenx",renamenxCommand,3,REDIS_CMD_INLINE,1,1,1},
-    {"expire",expireCommand,3,REDIS_CMD_INLINE,0,0,0},
-    {"expireat",expireatCommand,3,REDIS_CMD_INLINE,0,0,0},
-    {"keys",keysCommand,2,REDIS_CMD_INLINE,0,0,0},
-    {"dbsize",dbsizeCommand,1,REDIS_CMD_INLINE,0,0,0},
-    {"auth",authCommand,2,REDIS_CMD_INLINE,0,0,0},
-    {"ping",pingCommand,1,REDIS_CMD_INLINE,0,0,0},
-    {"echo",echoCommand,2,REDIS_CMD_BULK,0,0,0},
-    {"save",saveCommand,1,REDIS_CMD_INLINE,0,0,0},
-    {"bgsave",bgsaveCommand,1,REDIS_CMD_INLINE,0,0,0},
-    {"bgrewriteaof",bgrewriteaofCommand,1,REDIS_CMD_INLINE,0,0,0},
-    {"shutdown",shutdownCommand,1,REDIS_CMD_INLINE,0,0,0},
-    {"lastsave",lastsaveCommand,1,REDIS_CMD_INLINE,0,0,0},
-    {"type",typeCommand,2,REDIS_CMD_INLINE,1,1,1},
-    {"multi",multiCommand,1,REDIS_CMD_INLINE,0,0,0},
-    {"exec",execCommand,1,REDIS_CMD_INLINE,0,0,0},
-    {"discard",discardCommand,1,REDIS_CMD_INLINE,0,0,0},
-    {"sync",syncCommand,1,REDIS_CMD_INLINE,0,0,0},
-    {"flushdb",flushdbCommand,1,REDIS_CMD_INLINE,0,0,0},
-    {"flushall",flushallCommand,1,REDIS_CMD_INLINE,0,0,0},
-    {"sort",sortCommand,-2,REDIS_CMD_INLINE|REDIS_CMD_DENYOOM,1,1,1},
-    {"info",infoCommand,1,REDIS_CMD_INLINE,0,0,0},
-    {"monitor",monitorCommand,1,REDIS_CMD_INLINE,0,0,0},
-    {"ttl",ttlCommand,2,REDIS_CMD_INLINE,1,1,1},
-    {"slaveof",slaveofCommand,3,REDIS_CMD_INLINE,0,0,0},
-    {"debug",debugCommand,-2,REDIS_CMD_INLINE,0,0,0},
-    {NULL,NULL,0,0,0,0,0}
+    {"get",getCommand,2,REDIS_CMD_INLINE,NULL,1,1,1},
+    {"set",setCommand,3,REDIS_CMD_BULK|REDIS_CMD_DENYOOM,NULL,0,0,0},
+    {"setnx",setnxCommand,3,REDIS_CMD_BULK|REDIS_CMD_DENYOOM,NULL,0,0,0},
+    {"append",appendCommand,3,REDIS_CMD_BULK|REDIS_CMD_DENYOOM,NULL,1,1,1},
+    {"substr",substrCommand,4,REDIS_CMD_INLINE,NULL,1,1,1},
+    {"del",delCommand,-2,REDIS_CMD_INLINE,NULL,0,0,0},
+    {"exists",existsCommand,2,REDIS_CMD_INLINE,NULL,1,1,1},
+    {"incr",incrCommand,2,REDIS_CMD_INLINE|REDIS_CMD_DENYOOM,NULL,1,1,1},
+    {"decr",decrCommand,2,REDIS_CMD_INLINE|REDIS_CMD_DENYOOM,NULL,1,1,1},
+    {"mget",mgetCommand,-2,REDIS_CMD_INLINE,NULL,1,-1,1},
+    {"rpush",rpushCommand,3,REDIS_CMD_BULK|REDIS_CMD_DENYOOM,NULL,1,1,1},
+    {"lpush",lpushCommand,3,REDIS_CMD_BULK|REDIS_CMD_DENYOOM,NULL,1,1,1},
+    {"rpop",rpopCommand,2,REDIS_CMD_INLINE,NULL,1,1,1},
+    {"lpop",lpopCommand,2,REDIS_CMD_INLINE,NULL,1,1,1},
+    {"brpop",brpopCommand,-3,REDIS_CMD_INLINE,NULL,1,1,1},
+    {"blpop",blpopCommand,-3,REDIS_CMD_INLINE,NULL,1,1,1},
+    {"llen",llenCommand,2,REDIS_CMD_INLINE,NULL,1,1,1},
+    {"lindex",lindexCommand,3,REDIS_CMD_INLINE,NULL,1,1,1},
+    {"lset",lsetCommand,4,REDIS_CMD_BULK|REDIS_CMD_DENYOOM,NULL,1,1,1},
+    {"lrange",lrangeCommand,4,REDIS_CMD_INLINE,NULL,1,1,1},
+    {"ltrim",ltrimCommand,4,REDIS_CMD_INLINE,NULL,1,1,1},
+    {"lrem",lremCommand,4,REDIS_CMD_BULK,NULL,1,1,1},
+    {"rpoplpush",rpoplpushcommand,3,REDIS_CMD_INLINE|REDIS_CMD_DENYOOM,NULL,1,2,1},
+    {"sadd",saddCommand,3,REDIS_CMD_BULK|REDIS_CMD_DENYOOM,NULL,1,1,1},
+    {"srem",sremCommand,3,REDIS_CMD_BULK,NULL,1,1,1},
+    {"smove",smoveCommand,4,REDIS_CMD_BULK,NULL,1,2,1},
+    {"sismember",sismemberCommand,3,REDIS_CMD_BULK,NULL,1,1,1},
+    {"scard",scardCommand,2,REDIS_CMD_INLINE,NULL,1,1,1},
+    {"spop",spopCommand,2,REDIS_CMD_INLINE,NULL,1,1,1},
+    {"srandmember",srandmemberCommand,2,REDIS_CMD_INLINE,NULL,1,1,1},
+    {"sinter",sinterCommand,-2,REDIS_CMD_INLINE|REDIS_CMD_DENYOOM,NULL,1,-1,1},
+    {"sinterstore",sinterstoreCommand,-3,REDIS_CMD_INLINE|REDIS_CMD_DENYOOM,NULL,2,-1,1},
+    {"sunion",sunionCommand,-2,REDIS_CMD_INLINE|REDIS_CMD_DENYOOM,NULL,1,-1,1},
+    {"sunionstore",sunionstoreCommand,-3,REDIS_CMD_INLINE|REDIS_CMD_DENYOOM,NULL,2,-1,1},
+    {"sdiff",sdiffCommand,-2,REDIS_CMD_INLINE|REDIS_CMD_DENYOOM,NULL,1,-1,1},
+    {"sdiffstore",sdiffstoreCommand,-3,REDIS_CMD_INLINE|REDIS_CMD_DENYOOM,NULL,2,-1,1},
+    {"smembers",sinterCommand,2,REDIS_CMD_INLINE,NULL,1,1,1},
+    {"zadd",zaddCommand,4,REDIS_CMD_BULK|REDIS_CMD_DENYOOM,NULL,1,1,1},
+    {"zincrby",zincrbyCommand,4,REDIS_CMD_BULK|REDIS_CMD_DENYOOM,NULL,1,1,1},
+    {"zrem",zremCommand,3,REDIS_CMD_BULK,NULL,1,1,1},
+    {"zremrangebyscore",zremrangebyscoreCommand,4,REDIS_CMD_INLINE,NULL,1,1,1},
+    {"zremrangebyrank",zremrangebyrankCommand,4,REDIS_CMD_INLINE,NULL,1,1,1},
+    {"zunion",zunionCommand,-4,REDIS_CMD_INLINE|REDIS_CMD_DENYOOM,zunionInterBlockClientOnSwappedKeys,0,0,0},
+    {"zinter",zinterCommand,-4,REDIS_CMD_INLINE|REDIS_CMD_DENYOOM,zunionInterBlockClientOnSwappedKeys,0,0,0},
+    {"zrange",zrangeCommand,-4,REDIS_CMD_INLINE,NULL,1,1,1},
+    {"zrangebyscore",zrangebyscoreCommand,-4,REDIS_CMD_INLINE,NULL,1,1,1},
+    {"zcount",zcountCommand,4,REDIS_CMD_INLINE,NULL,1,1,1},
+    {"zrevrange",zrevrangeCommand,-4,REDIS_CMD_INLINE,NULL,1,1,1},
+    {"zcard",zcardCommand,2,REDIS_CMD_INLINE,NULL,1,1,1},
+    {"zscore",zscoreCommand,3,REDIS_CMD_BULK|REDIS_CMD_DENYOOM,NULL,1,1,1},
+    {"zrank",zrankCommand,3,REDIS_CMD_BULK,NULL,1,1,1},
+    {"zrevrank",zrevrankCommand,3,REDIS_CMD_BULK,NULL,1,1,1},
+    {"hset",hsetCommand,4,REDIS_CMD_BULK|REDIS_CMD_DENYOOM,NULL,1,1,1},
+    {"hmset",hmsetCommand,-4,REDIS_CMD_BULK|REDIS_CMD_DENYOOM,NULL,1,1,1},
+    {"hincrby",hincrbyCommand,4,REDIS_CMD_INLINE|REDIS_CMD_DENYOOM,NULL,1,1,1},
+    {"hget",hgetCommand,3,REDIS_CMD_BULK,NULL,1,1,1},
+    {"hdel",hdelCommand,3,REDIS_CMD_BULK,NULL,1,1,1},
+    {"hlen",hlenCommand,2,REDIS_CMD_INLINE,NULL,1,1,1},
+    {"hkeys",hkeysCommand,2,REDIS_CMD_INLINE,NULL,1,1,1},
+    {"hvals",hvalsCommand,2,REDIS_CMD_INLINE,NULL,1,1,1},
+    {"hgetall",hgetallCommand,2,REDIS_CMD_INLINE,NULL,1,1,1},
+    {"hexists",hexistsCommand,3,REDIS_CMD_BULK,NULL,1,1,1},
+    {"incrby",incrbyCommand,3,REDIS_CMD_INLINE|REDIS_CMD_DENYOOM,NULL,1,1,1},
+    {"decrby",decrbyCommand,3,REDIS_CMD_INLINE|REDIS_CMD_DENYOOM,NULL,1,1,1},
+    {"getset",getsetCommand,3,REDIS_CMD_BULK|REDIS_CMD_DENYOOM,NULL,1,1,1},
+    {"mset",msetCommand,-3,REDIS_CMD_BULK|REDIS_CMD_DENYOOM,NULL,1,-1,2},
+    {"msetnx",msetnxCommand,-3,REDIS_CMD_BULK|REDIS_CMD_DENYOOM,NULL,1,-1,2},
+    {"randomkey",randomkeyCommand,1,REDIS_CMD_INLINE,NULL,0,0,0},
+    {"select",selectCommand,2,REDIS_CMD_INLINE,NULL,0,0,0},
+    {"move",moveCommand,3,REDIS_CMD_INLINE,NULL,1,1,1},
+    {"rename",renameCommand,3,REDIS_CMD_INLINE,NULL,1,1,1},
+    {"renamenx",renamenxCommand,3,REDIS_CMD_INLINE,NULL,1,1,1},
+    {"expire",expireCommand,3,REDIS_CMD_INLINE,NULL,0,0,0},
+    {"expireat",expireatCommand,3,REDIS_CMD_INLINE,NULL,0,0,0},
+    {"keys",keysCommand,2,REDIS_CMD_INLINE,NULL,0,0,0},
+    {"dbsize",dbsizeCommand,1,REDIS_CMD_INLINE,NULL,0,0,0},
+    {"auth",authCommand,2,REDIS_CMD_INLINE,NULL,0,0,0},
+    {"ping",pingCommand,1,REDIS_CMD_INLINE,NULL,0,0,0},
+    {"echo",echoCommand,2,REDIS_CMD_BULK,NULL,0,0,0},
+    {"save",saveCommand,1,REDIS_CMD_INLINE,NULL,0,0,0},
+    {"bgsave",bgsaveCommand,1,REDIS_CMD_INLINE,NULL,0,0,0},
+    {"bgrewriteaof",bgrewriteaofCommand,1,REDIS_CMD_INLINE,NULL,0,0,0},
+    {"shutdown",shutdownCommand,1,REDIS_CMD_INLINE,NULL,0,0,0},
+    {"lastsave",lastsaveCommand,1,REDIS_CMD_INLINE,NULL,0,0,0},
+    {"type",typeCommand,2,REDIS_CMD_INLINE,NULL,1,1,1},
+    {"multi",multiCommand,1,REDIS_CMD_INLINE,NULL,0,0,0},
+    {"exec",execCommand,1,REDIS_CMD_INLINE|REDIS_CMD_DENYOOM,NULL,0,0,0},
+    {"discard",discardCommand,1,REDIS_CMD_INLINE,NULL,0,0,0},
+    {"sync",syncCommand,1,REDIS_CMD_INLINE,NULL,0,0,0},
+    {"flushdb",flushdbCommand,1,REDIS_CMD_INLINE,NULL,0,0,0},
+    {"flushall",flushallCommand,1,REDIS_CMD_INLINE,NULL,0,0,0},
+    {"sort",sortCommand,-2,REDIS_CMD_INLINE|REDIS_CMD_DENYOOM,NULL,1,1,1},
+    {"info",infoCommand,1,REDIS_CMD_INLINE,NULL,0,0,0},
+    {"monitor",monitorCommand,1,REDIS_CMD_INLINE,NULL,0,0,0},
+    {"ttl",ttlCommand,2,REDIS_CMD_INLINE,NULL,1,1,1},
+    {"slaveof",slaveofCommand,3,REDIS_CMD_INLINE,NULL,0,0,0},
+    {"debug",debugCommand,-2,REDIS_CMD_INLINE,NULL,0,0,0},
+    {"config",configCommand,-2,REDIS_CMD_BULK,NULL,0,0,0},
+    {"subscribe",subscribeCommand,-2,REDIS_CMD_INLINE,NULL,0,0,0},
+    {"unsubscribe",unsubscribeCommand,-1,REDIS_CMD_INLINE,NULL,0,0,0},
+    {"psubscribe",psubscribeCommand,-2,REDIS_CMD_INLINE,NULL,0,0,0},
+    {"punsubscribe",punsubscribeCommand,-1,REDIS_CMD_INLINE,NULL,0,0,0},
+    {"publish",publishCommand,3,REDIS_CMD_BULK|REDIS_CMD_FORCE_REPLICATION,NULL,0,0,0},
+    {NULL,NULL,0,0,NULL,0,0,0}
 };
 
 /*============================ Utility functions ============================ */
 
 /* Glob-style pattern matching. */
-int stringmatchlen(const char *pattern, int patternLen,
+static int stringmatchlen(const char *pattern, int patternLen,
         const char *string, int stringLen, int nocase)
 {
     while(patternLen) {
@@ -919,6 +959,10 @@ int stringmatchlen(const char *pattern, int patternLen,
     return 0;
 }
 
+static int stringmatch(const char *pattern, const char *string, int nocase) {
+    return stringmatchlen(pattern,strlen(pattern),string,strlen(string),nocase);
+}
+
 static void redisLog(int level, const char *fmt, ...) {
     va_list ap;
     FILE *fp;
@@ -1000,6 +1044,10 @@ static int dictEncObjKeyCompare(void *privdata, const void *key1,
     robj *o1 = (robj*) key1, *o2 = (robj*) key2;
     int cmp;
 
+    if (o1->encoding == REDIS_ENCODING_INT &&
+        o2->encoding == REDIS_ENCODING_INT &&
+        o1->ptr == o2->ptr) return 1;
+
     o1 = getDecodedObject(o1);
     o2 = getDecodedObject(o2);
     cmp = sdsDictKeyCompare(privdata,o1->ptr,o2->ptr);
@@ -1093,6 +1141,8 @@ static dictType keylistDictType = {
     dictListDestructor          /* val destructor */
 };
 
+static void version();
+
 /* ========================= Random utility functions ======================= */
 
 /* Redis generally does not try to recover from out of memory conditions
@@ -1119,7 +1169,9 @@ static void closeTimedoutClients(void) {
         if (server.maxidletime &&
             !(c->flags & REDIS_SLAVE) &&    /* no timeout for slaves */
             !(c->flags & REDIS_MASTER) &&   /* no timeout for masters */
-             (now - c->lastinteraction > server.maxidletime))
+            dictSize(c->pubsub_channels) == 0 && /* no timeout for pubsub */
+            listLength(c->pubsub_patterns) == 0 &&
+            (now - c->lastinteraction > server.maxidletime))
         {
             redisLog(REDIS_VERBOSE,"Closing idle client");
             freeClient(c);
@@ -1171,7 +1223,7 @@ void backgroundSaveDoneHandler(int statloc) {
         redisLog(REDIS_WARNING, "Background saving error");
     } else {
         redisLog(REDIS_WARNING,
-            "Background saving terminated by signal");
+            "Background saving terminated by signal %d", WTERMSIG(statloc));
         rdbRemoveTempFile(server.bgsavechildpid);
     }
     server.bgsavechildpid = -1;
@@ -1232,7 +1284,8 @@ void backgroundRewriteDoneHandler(int statloc) {
         redisLog(REDIS_WARNING, "Background append only file rewriting error");
     } else {
         redisLog(REDIS_WARNING,
-            "Background append only file rewriting terminated by signal");
+            "Background append only file rewriting terminated by signal %d",
+            WTERMSIG(statloc));
     }
 cleanup:
     sdsfree(server.bgrewritebuf);
@@ -1241,6 +1294,19 @@ cleanup:
     server.bgrewritechildpid = -1;
 }
 
+/* This function is called once a background process of some kind terminates,
+ * as we want to avoid resizing the hash tables when there is a child in order
+ * to play well with copy-on-write (otherwise when a resize happens lots of
+ * memory pages are copied). The goal of this function is to update the ability
+ * for dict.c to resize the hash tables accordingly to the fact we have o not
+ * running childs. */
+static void updateDictResizePolicy(void) {
+    if (server.bgsavechildpid == -1 && server.bgrewritechildpid == -1)
+        dictEnableResize();
+    else
+        dictDisableResize();
+}
+
 static int serverCron(struct aeEventLoop *eventLoop, long long id, void *clientData) {
     int j, loops = server.cronloops++;
     REDIS_NOTUSED(eventLoop);
@@ -1260,7 +1326,7 @@ static int serverCron(struct aeEventLoop *eventLoop, long long id, void *clientD
         size = dictSlots(server.db[j].dict);
         used = dictSize(server.db[j].dict);
         vkeys = dictSize(server.db[j].expires);
-        if (!(loops % 5) && (used || vkeys)) {
+        if (!(loops % 50) && (used || vkeys)) {
             redisLog(REDIS_VERBOSE,"DB %d: %lld keys (%lld volatile) in %lld slots HT.",j,used,vkeys,size);
             /* dictPrintStats(server.dict); */
         }
@@ -1272,19 +1338,22 @@ static int serverCron(struct aeEventLoop *eventLoop, long long id, void *clientD
      * if we resize the HT while there is the saving child at work actually
      * a lot of memory movements in the parent will cause a lot of pages
      * copied. */
-    if (server.bgsavechildpid == -1) tryResizeHashTables();
+    if (server.bgsavechildpid == -1 && server.bgrewritechildpid == -1 &&
+        !(loops % 10))
+    {
+        tryResizeHashTables();
+    }
 
     /* Show information about connected clients */
-    if (!(loops % 5)) {
-        redisLog(REDIS_VERBOSE,"%d clients connected (%d slaves), %zu bytes in use, %d shared objects",
+    if (!(loops % 50)) {
+        redisLog(REDIS_VERBOSE,"%d clients connected (%d slaves), %zu bytes in use",
             listLength(server.clients)-listLength(server.slaves),
             listLength(server.slaves),
-            zmalloc_used_memory(),
-            dictSize(server.sharingpool));
+            zmalloc_used_memory());
     }
 
     /* Close connections of timedout clients */
-    if ((server.maxidletime && !(loops % 10)) || server.blpop_blocked_clients)
+    if ((server.maxidletime && !(loops % 100)) || server.blpop_blocked_clients)
         closeTimedoutClients();
 
     /* Check if a background saving or AOF rewrite in progress terminated */
@@ -1298,6 +1367,7 @@ static int serverCron(struct aeEventLoop *eventLoop, long long id, void *clientD
             } else {
                 backgroundRewriteDoneHandler(statloc);
             }
+            updateDictResizePolicy();
         }
     } else {
         /* If there is not a background saving in progress check if
@@ -1342,6 +1412,7 @@ static int serverCron(struct aeEventLoop *eventLoop, long long id, void *clientD
                 if (now > t) {
                     deleteKey(db,dictGetEntryKey(de));
                     expired++;
+                    server.stat_expiredkeys++;
                 }
             }
         } while (expired > REDIS_EXPIRELOOKUPS_PER_CRON/4);
@@ -1359,7 +1430,7 @@ static int serverCron(struct aeEventLoop *eventLoop, long long id, void *clientD
             retval = (server.vm_max_threads == 0) ?
                         vmSwapOneObjectBlocking() :
                         vmSwapOneObjectThreaded();
-            if (retval == REDIS_ERR && (loops % 30) == 0 &&
+            if (retval == REDIS_ERR && !(loops % 300) &&
                 zmalloc_used_memory() >
                 (server.vm_max_memory+server.vm_max_memory/10))
             {
@@ -1374,13 +1445,13 @@ static int serverCron(struct aeEventLoop *eventLoop, long long id, void *clientD
     }
 
     /* Check if we should connect to a MASTER */
-    if (server.replstate == REDIS_REPL_CONNECT) {
+    if (server.replstate == REDIS_REPL_CONNECT && !(loops % 10)) {
         redisLog(REDIS_NOTICE,"Connecting to MASTER...");
         if (syncWithMaster() == REDIS_OK) {
             redisLog(REDIS_NOTICE,"MASTER <-> SLAVE sync succeeded");
         }
     }
-    return 1000;
+    return 100;
 }
 
 /* This function gets called every time Redis is entering the
@@ -1416,6 +1487,8 @@ static void beforeSleep(struct aeEventLoop *eventLoop) {
 }
 
 static void createSharedObjects(void) {
+    int j;
+
     shared.crlf = createObject(REDIS_STRING,sdsnew("\r\n"));
     shared.ok = createObject(REDIS_STRING,sdsnew("+OK\r\n"));
     shared.err = createObject(REDIS_STRING,sdsnew("-ERR\r\n"));
@@ -1450,6 +1523,16 @@ static void createSharedObjects(void) {
     shared.select7 = createStringObject("select 7\r\n",10);
     shared.select8 = createStringObject("select 8\r\n",10);
     shared.select9 = createStringObject("select 9\r\n",10);
+    shared.messagebulk = createStringObject("$7\r\nmessage\r\n",13);
+    shared.subscribebulk = createStringObject("$9\r\nsubscribe\r\n",15);
+    shared.unsubscribebulk = createStringObject("$11\r\nunsubscribe\r\n",18);
+    shared.psubscribebulk = createStringObject("$10\r\npsubscribe\r\n",17);
+    shared.punsubscribebulk = createStringObject("$12\r\npunsubscribe\r\n",19);
+    shared.mbulk3 = createStringObject("*3\r\n",4);
+    for (j = 0; j < REDIS_SHARED_INTEGERS; j++) {
+        shared.integers[j] = createObject(REDIS_STRING,(void*)(long)j);
+        shared.integers[j]->encoding = REDIS_ENCODING_INT;
+    }
 }
 
 static void appendServerSaveParams(time_t seconds, int changes) {
@@ -1480,13 +1563,12 @@ static void initServerConfig() {
     server.lastfsync = time(NULL);
     server.appendfd = -1;
     server.appendseldb = -1; /* Make sure the first time will not match */
-    server.pidfile = "/var/run/redis.pid";
-    server.dbfilename = "dump.rdb";
-    server.appendfilename = "appendonly.aof";
+    server.pidfile = zstrdup("/var/run/redis.pid");
+    server.dbfilename = zstrdup("dump.rdb");
+    server.appendfilename = zstrdup("appendonly.aof");
     server.requirepass = NULL;
     server.shareobjects = 0;
     server.rdbcompression = 1;
-    server.sharingpoolsize = 1024;
     server.maxclients = 0;
     server.blpop_blocked_clients = 0;
     server.maxmemory = 0;
@@ -1539,7 +1621,6 @@ static void initServer() {
     createSharedObjects();
     server.el = aeCreateEventLoop();
     server.db = zmalloc(sizeof(redisDb)*server.dbnum);
-    server.sharingpool = dictCreate(&setDictType,NULL);
     server.fd = anetTcpServer(server.neterr, server.port, server.bindaddr);
     if (server.fd == -1) {
         redisLog(REDIS_WARNING, "Opening TCP port: %s", server.neterr);
@@ -1553,6 +1634,10 @@ static void initServer() {
             server.db[j].io_keys = dictCreate(&keylistDictType,NULL);
         server.db[j].id = j;
     }
+    server.pubsub_channels = dictCreate(&keylistDictType,NULL);
+    server.pubsub_patterns = listCreate();
+    listSetFreeMethod(server.pubsub_patterns,freePubsubPattern);
+    listSetMatchMethod(server.pubsub_patterns,listMatchPubsubPattern);
     server.cronloops = 0;
     server.bgsavechildpid = -1;
     server.bgrewritechildpid = -1;
@@ -1561,6 +1646,7 @@ static void initServer() {
     server.dirty = 0;
     server.stat_numcommands = 0;
     server.stat_numconnections = 0;
+    server.stat_expiredkeys = 0;
     server.stat_starttime = time(NULL);
     server.unixtime = time(NULL);
     aeCreateTimeEvent(server.el, 1, serverCron, NULL, NULL);
@@ -1605,12 +1691,15 @@ static void loadServerConfig(char *filename) {
     char buf[REDIS_CONFIGLINE_MAX+1], *err = NULL;
     int linenum = 0;
     sds line = NULL;
+    char *errormsg = "Fatal error, can't open config file '%s'";
+    char *errorbuf = zmalloc(sizeof(char)*(strlen(errormsg)+strlen(filename)));
+    sprintf(errorbuf, errormsg, filename);
 
     if (filename[0] == '-' && filename[1] == '\0')
         fp = stdin;
     else {
         if ((fp = fopen(filename,"r")) == NULL) {
-            redisLog(REDIS_WARNING,"Fatal error, can't open config file");
+            redisLog(REDIS_WARNING, errorbuf);
             exit(1);
         }
     }
@@ -1692,6 +1781,8 @@ static void loadServerConfig(char *filename) {
             if (server.dbnum < 1) {
                 err = "Invalid number of databases"; goto loaderr;
             }
+        } else if (!strcasecmp(argv[0],"include") && argc == 2) {
+            loadServerConfig(argv[1]);
         } else if (!strcasecmp(argv[0],"maxclients") && argc == 2) {
             server.maxclients = atoi(argv[1]);
         } else if (!strcasecmp(argv[0],"maxmemory") && argc == 2) {
@@ -1714,11 +1805,6 @@ static void loadServerConfig(char *filename) {
             if ((server.rdbcompression = yesnotoi(argv[1])) == -1) {
                 err = "argument must be 'yes' or 'no'"; goto loaderr;
             }
-        } else if (!strcasecmp(argv[0],"shareobjectspoolsize") && argc == 2) {
-            server.sharingpoolsize = atoi(argv[1]);
-            if (server.sharingpoolsize < 1) {
-                err = "invalid object sharing pool size"; goto loaderr;
-            }
         } else if (!strcasecmp(argv[0],"daemonize") && argc == 2) {
             if ((server.daemonize = yesnotoi(argv[1])) == -1) {
                 err = "argument must be 'yes' or 'no'"; goto loaderr;
@@ -1741,8 +1827,10 @@ static void loadServerConfig(char *filename) {
         } else if (!strcasecmp(argv[0],"requirepass") && argc == 2) {
             server.requirepass = zstrdup(argv[1]);
         } else if (!strcasecmp(argv[0],"pidfile") && argc == 2) {
+            zfree(server.pidfile);
             server.pidfile = zstrdup(argv[1]);
         } else if (!strcasecmp(argv[0],"dbfilename") && argc == 2) {
+            zfree(server.dbfilename);
             server.dbfilename = zstrdup(argv[1]);
         } else if (!strcasecmp(argv[0],"vm-enabled") && argc == 2) {
             if ((server.vm_enabled = yesnotoi(argv[1])) == -1) {
@@ -1808,6 +1896,12 @@ static void freeClient(redisClient *c) {
     if (c->flags & REDIS_BLOCKED)
         unblockClientWaitingData(c);
 
+    /* Unsubscribe from all the pubsub channels */
+    pubsubUnsubscribeAllChannels(c,0);
+    pubsubUnsubscribeAllPatterns(c,0);
+    dictRelease(c->pubsub_channels);
+    listRelease(c->pubsub_patterns);
+    /* Obvious cleanup */
     aeDeleteFileEvent(server.el,c->fd,AE_READABLE);
     aeDeleteFileEvent(server.el,c->fd,AE_WRITABLE);
     listRelease(c->reply);
@@ -1830,7 +1924,7 @@ static void freeClient(redisClient *c) {
         dontWaitForSwappedKey(c,ln->value);
     }
     listRelease(c->io_keys);
-    /* Other cleanup */
+    /* Master/slave cleanup */
     if (c->flags & REDIS_SLAVE) {
         if (c->replstate == REDIS_REPL_SEND_BULK && c->repldbfd != -1)
             close(c->repldbfd);
@@ -1843,6 +1937,7 @@ static void freeClient(redisClient *c) {
         server.master = NULL;
         server.replstate = REDIS_REPL_CONNECT;
     }
+    /* Release memory */
     zfree(c->argv);
     zfree(c->mbargv);
     freeClientMultiState(c);
@@ -1886,7 +1981,7 @@ static void sendReplyToClient(aeEventLoop *el, int fd, void *privdata, int mask)
 
     /* Use writev() if we have enough buffers to send */
     if (!server.glueoutputbuf &&
-        listLength(c->reply) > REDIS_WRITEV_THRESHOLD && 
+        listLength(c->reply) > REDIS_WRITEV_THRESHOLD &&
         !(c->flags & REDIS_MASTER))
     {
         sendReplyToClientWritev(el, fd, privdata, mask);
@@ -1964,7 +2059,7 @@ static void sendReplyToClientWritev(aeEventLoop *el, int fd, void *privdata, int
             o = listNodeValue(node);
             objlen = sdslen(o->ptr);
 
-            if (totwritten + objlen - offset > REDIS_MAX_WRITE_PER_EVENT) 
+            if (totwritten + objlen - offset > REDIS_MAX_WRITE_PER_EVENT)
                 break;
 
             if(ion == REDIS_WRITEV_IOVEC_COUNT)
@@ -2012,7 +2107,7 @@ static void sendReplyToClientWritev(aeEventLoop *el, int fd, void *privdata, int
         }
     }
 
-    if (totwritten > 0) 
+    if (totwritten > 0)
         c->lastinteraction = time(NULL);
 
     if (listLength(c->reply) == 0) {
@@ -2043,12 +2138,15 @@ static void call(redisClient *c, struct redisCommand *cmd) {
 
     dirty = server.dirty;
     cmd->proc(c);
-    if (server.appendonly && server.dirty-dirty)
+    dirty = server.dirty-dirty;
+
+    if (server.appendonly && dirty)
         feedAppendOnlyFile(cmd,c->db->id,c->argv,c->argc);
-    if (server.dirty-dirty && listLength(server.slaves))
-        replicationFeedSlaves(server.slaves,cmd,c->db->id,c->argv,c->argc);
+    if ((dirty || cmd->flags & REDIS_CMD_FORCE_REPLICATION) &&
+        listLength(server.slaves))
+        replicationFeedSlaves(server.slaves,c->db->id,c->argv,c->argc);
     if (listLength(server.monitors))
-        replicationFeedSlaves(server.monitors,cmd,c->db->id,c->argv,c->argc);
+        replicationFeedSlaves(server.monitors,c->db->id,c->argv,c->argc);
     server.stat_numcommands++;
 }
 
@@ -2158,10 +2256,6 @@ static int processCommand(redisClient *c) {
                 cmd->name));
         resetClient(c);
         return 1;
-    } else if (server.maxmemory && cmd->flags & REDIS_CMD_DENYOOM && zmalloc_used_memory() > server.maxmemory) {
-        addReplySds(c,sdsnew("-ERR command not allowed when used memory > 'maxmemory'\r\n"));
-        resetClient(c);
-        return 1;
     } else if (cmd->flags & REDIS_CMD_BULK && c->bulklen == -1) {
         /* This is a bulk command, we have to read the last argument yet. */
         int bulklen = atoi(c->argv[c->argc-1]->ptr);
@@ -2190,15 +2284,9 @@ static int processCommand(redisClient *c) {
             return 1;
         }
     }
-    /* Let's try to share objects on the command arguments vector */
-    if (server.shareobjects) {
-        int j;
-        for(j = 1; j < c->argc; j++)
-            c->argv[j] = tryObjectSharing(c->argv[j]);
-    }
     /* Let's try to encode the bulk object to save space. */
     if (cmd->flags & REDIS_CMD_BULK)
-        tryObjectEncoding(c->argv[c->argc-1]);
+        c->argv[c->argc-1] = tryObjectEncoding(c->argv[c->argc-1]);
 
     /* Check if the user is authenticated */
     if (server.requirepass && !c->authenticated && cmd->proc != authCommand) {
@@ -2207,6 +2295,24 @@ static int processCommand(redisClient *c) {
         return 1;
     }
 
+    /* Handle the maxmemory directive */
+    if (server.maxmemory && (cmd->flags & REDIS_CMD_DENYOOM) &&
+        zmalloc_used_memory() > server.maxmemory)
+    {
+        addReplySds(c,sdsnew("-ERR command not allowed when used memory > 'maxmemory'\r\n"));
+        resetClient(c);
+        return 1;
+    }
+
+    /* Only allow SUBSCRIBE and UNSUBSCRIBE in the context of Pub/Sub */
+    if (dictSize(c->pubsub_channels) > 0 &&
+        cmd->proc != subscribeCommand && cmd->proc != unsubscribeCommand &&
+        cmd->proc != psubscribeCommand && cmd->proc != punsubscribeCommand) {
+        addReplySds(c,sdsnew("-ERR only (P)SUBSCRIBE / (P)UNSUBSCRIBE / QUIT allowed in this context\r\n"));
+        resetClient(c);
+        return 1;
+    }
+
     /* Exec the command */
     if (c->flags & REDIS_MULTI && cmd->proc != execCommand && cmd->proc != discardCommand) {
         queueMultiCommand(c,cmd);
@@ -2222,34 +2328,36 @@ static int processCommand(redisClient *c) {
     return 1;
 }
 
-static void replicationFeedSlaves(list *slaves, struct redisCommand *cmd, int dictid, robj **argv, int argc) {
+static void replicationFeedSlaves(list *slaves, int dictid, robj **argv, int argc) {
     listNode *ln;
     listIter li;
     int outc = 0, j;
     robj **outv;
-    /* (args*2)+1 is enough room for args, spaces, newlines */
-    robj *static_outv[REDIS_STATIC_ARGS*2+1];
+    /* We need 1+(ARGS*3) objects since commands are using the new protocol
+     * and we one 1 object for the first "*<count>\r\n" multibulk count, then
+     * for every additional object we have "$<count>\r\n" + object + "\r\n". */
+    robj *static_outv[REDIS_STATIC_ARGS*3+1];
+    robj *lenobj;
 
     if (argc <= REDIS_STATIC_ARGS) {
         outv = static_outv;
     } else {
-        outv = zmalloc(sizeof(robj*)*(argc*2+1));
+        outv = zmalloc(sizeof(robj*)*(argc*3+1));
     }
-    
-    for (j = 0; j < argc; j++) {
-        if (j != 0) outv[outc++] = shared.space;
-        if ((cmd->flags & REDIS_CMD_BULK) && j == argc-1) {
-            robj *lenobj;
 
-            lenobj = createObject(REDIS_STRING,
-                sdscatprintf(sdsempty(),"%lu\r\n",
-                    (unsigned long) stringObjectLen(argv[j])));
-            lenobj->refcount = 0;
-            outv[outc++] = lenobj;
-        }
+    lenobj = createObject(REDIS_STRING,
+            sdscatprintf(sdsempty(), "*%d\r\n", argc));
+    lenobj->refcount = 0;
+    outv[outc++] = lenobj;
+    for (j = 0; j < argc; j++) {
+        lenobj = createObject(REDIS_STRING,
+            sdscatprintf(sdsempty(),"$%lu\r\n",
+                (unsigned long) stringObjectLen(argv[j])));
+        lenobj->refcount = 0;
+        outv[outc++] = lenobj;
         outv[outc++] = argv[j];
+        outv[outc++] = shared.crlf;
     }
-    outv[outc++] = shared.crlf;
 
     /* Increment all the refcounts at start and decrement at end in order to
      * be sure to free objects if there is no slave in a replication state
@@ -2309,7 +2417,7 @@ again:
         if (p) {
             sds query, *argv;
             int argc, j;
-            
+
             query = c->querybuf;
             c->querybuf = sdsempty();
             querylen = 1+(p-(query));
@@ -2401,8 +2509,7 @@ static void readQueryFromClient(aeEventLoop *el, int fd, void *privdata, int mas
     } else {
         return;
     }
-    if (!(c->flags & REDIS_BLOCKED))
-        processInputBuffer(c);
+    processInputBuffer(c);
 }
 
 static int selectDb(redisClient *c, int id) {
@@ -2417,6 +2524,10 @@ static void *dupClientReplyValue(void *o) {
     return o;
 }
 
+static int listMatchObjects(void *a, void *b) {
+    return compareStringObjects(a,b) == 0;
+}
+
 static redisClient *createClient(int fd) {
     redisClient *c = zmalloc(sizeof(*c));
 
@@ -2444,6 +2555,10 @@ static redisClient *createClient(int fd) {
     c->blockingkeysnum = 0;
     c->io_keys = listCreate();
     listSetFreeMethod(c->io_keys,decrRefCount);
+    c->pubsub_channels = dictCreate(&setDictType,NULL);
+    c->pubsub_patterns = listCreate();
+    listSetFreeMethod(c->pubsub_patterns,decrRefCount);
+    listSetMatchMethod(c->pubsub_patterns,listMatchObjects);
     if (aeCreateFileEvent(server.el, c->fd, AE_READABLE,
         readQueryFromClient, c) == AE_ERR) {
         freeClient(c);
@@ -2497,6 +2612,21 @@ static void addReplyLong(redisClient *c, long l) {
     addReplySds(c,sdsnewlen(buf,len));
 }
 
+static void addReplyLongLong(redisClient *c, long long ll) {
+    char buf[128];
+    size_t len;
+
+    if (ll == 0) {
+        addReply(c,shared.czero);
+        return;
+    } else if (ll == 1) {
+        addReply(c,shared.cone);
+        return;
+    }
+    len = snprintf(buf,sizeof(buf),":%lld\r\n",ll);
+    addReplySds(c,sdsnewlen(buf,len));
+}
+
 static void addReplyUlong(redisClient *c, unsigned long ul) {
     char buf[128];
     size_t len;
@@ -2539,6 +2669,17 @@ static void addReplyBulk(redisClient *c, robj *obj) {
     addReply(c,shared.crlf);
 }
 
+/* In the CONFIG command we need to add vanilla C string as bulk replies */
+static void addReplyBulkCString(redisClient *c, char *s) {
+    if (s == NULL) {
+        addReply(c,shared.nullbulk);
+    } else {
+        robj *o = createStringObject(s,strlen(s));
+        addReplyBulk(c,o);
+        decrRefCount(o);
+    }
+}
+
 static void acceptHandler(aeEventLoop *el, int fd, void *privdata, int mask) {
     int cport, cfd;
     char cip[128];
@@ -2685,7 +2826,6 @@ static void freeHashObject(robj *o) {
 }
 
 static void incrRefCount(robj *o) {
-    redisAssert(!server.vm_enabled || o->storage == REDIS_VM_MEMORY);
     o->refcount++;
 }
 
@@ -2697,9 +2837,6 @@ static void decrRefCount(void *obj) {
     if (server.vm_enabled &&
         (o->storage == REDIS_VM_SWAPPED || o->storage == REDIS_VM_LOADING))
     {
-        if (o->storage == REDIS_VM_SWAPPED || o->storage == REDIS_VM_LOADING) {
-            redisAssert(o->refcount == 1);
-        }
         if (o->storage == REDIS_VM_LOADING) vmCancelThreadedIOJob(obj);
         redisAssert(o->type == REDIS_STRING);
         freeStringObject(o);
@@ -2812,51 +2949,6 @@ static int deleteKey(redisDb *db, robj *key) {
     return retval == DICT_OK;
 }
 
-/* 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;
-
-    redisAssert(o->type == REDIS_STRING);
-    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);
-            redisAssert(de != NULL);
-            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;
-    }
-}
-
 /* Check if the nul-terminated string 's' can be represented by a long
  * (that is, is a number that fits into long without any other space or
  * character before or after the digits).
@@ -2867,7 +2959,7 @@ static int isStringRepresentableAsLong(sds s, long *longval) {
     char buf[32], *endptr;
     long value;
     int slen;
-    
+
     value = strtol(s, &endptr, 10);
     if (endptr[0] != '\0') return REDIS_ERR;
     slen = snprintf(buf,32,"%ld",value);
@@ -2880,36 +2972,42 @@ static int isStringRepresentableAsLong(sds s, long *longval) {
 }
 
 /* Try to encode a string object in order to save space */
-static int tryObjectEncoding(robj *o) {
+static robj *tryObjectEncoding(robj *o) {
     long value;
     sds s = o->ptr;
 
     if (o->encoding != REDIS_ENCODING_RAW)
-        return REDIS_ERR; /* Already encoded */
+        return o; /* Already encoded */
 
-    /* It's not save to encode shared objects: shared objects can be shared
+    /* 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 REDIS_ERR;
+     if (o->refcount > 1) return o;
 
     /* Currently we try to encode only strings */
     redisAssert(o->type == REDIS_STRING);
 
     /* Check if we can represent this string as a long integer */
-    if (isStringRepresentableAsLong(s,&value) == REDIS_ERR) return REDIS_ERR;
+    if (isStringRepresentableAsLong(s,&value) == REDIS_ERR) return o;
 
     /* Ok, this object can be encoded */
-    o->encoding = REDIS_ENCODING_INT;
-    sdsfree(o->ptr);
-    o->ptr = (void*) value;
-    return REDIS_OK;
+    if (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;
+    }
 }
 
 /* Get a decoded version of an encoded object (returned as a new object).
  * If the object is already raw-encoded just increment the ref count. */
 static robj *getDecodedObject(robj *o) {
     robj *dec;
-    
+
     if (o->encoding == REDIS_ENCODING_RAW) {
         incrRefCount(o);
         return o;
@@ -3239,7 +3337,7 @@ static off_t rdbSavedObjectLen(robj *o, FILE *fp) {
 /* Return the number of pages required to save this object in the swap file */
 static off_t rdbSavedObjectPages(robj *o, FILE *fp) {
     off_t bytes = rdbSavedObjectLen(o,fp);
-    
+
     return (bytes+(server.vm_page_size-1))/server.vm_page_size;
 }
 
@@ -3322,7 +3420,7 @@ static int rdbSave(char *filename) {
     fflush(fp);
     fsync(fileno(fp));
     fclose(fp);
-    
+
     /* Use RENAME to make sure the DB file is changed atomically only
      * if the generate DB file is ok. */
     if (rename(tmpfile,filename) == -1) {
@@ -3366,6 +3464,7 @@ static int rdbSaveBackground(char *filename) {
         }
         redisLog(REDIS_NOTICE,"Background saving started by pid %d",childpid);
         server.bgsavechildpid = childpid;
+        updateDictResizePolicy();
         return REDIS_OK;
     }
     return REDIS_OK; /* unreached */
@@ -3475,9 +3574,9 @@ static robj *rdbLoadStringObject(FILE*fp) {
         case REDIS_RDB_ENC_INT8:
         case REDIS_RDB_ENC_INT16:
         case REDIS_RDB_ENC_INT32:
-            return tryObjectSharing(rdbLoadIntegerObject(fp,len));
+            return rdbLoadIntegerObject(fp,len);
         case REDIS_RDB_ENC_LZF:
-            return tryObjectSharing(rdbLoadLzfStringObject(fp));
+            return rdbLoadLzfStringObject(fp);
         default:
             redisAssert(0);
         }
@@ -3489,7 +3588,7 @@ static robj *rdbLoadStringObject(FILE*fp) {
         sdsfree(val);
         return NULL;
     }
-    return tryObjectSharing(createObject(REDIS_STRING,val));
+    return createObject(REDIS_STRING,val);
 }
 
 /* For information about double serialization check rdbSaveDoubleValue() */
@@ -3519,7 +3618,7 @@ static robj *rdbLoadObject(int type, FILE *fp) {
     if (type == REDIS_STRING) {
         /* Read string value */
         if ((o = rdbLoadStringObject(fp)) == NULL) return NULL;
-        tryObjectEncoding(o);
+        o = tryObjectEncoding(o);
     } else if (type == REDIS_LIST || type == REDIS_SET) {
         /* Read list/set value */
         uint32_t listlen;
@@ -3535,7 +3634,7 @@ static robj *rdbLoadObject(int type, FILE *fp) {
             robj *ele;
 
             if ((ele = rdbLoadStringObject(fp)) == NULL) return NULL;
-            tryObjectEncoding(ele);
+            ele = tryObjectEncoding(ele);
             if (type == REDIS_LIST) {
                 listAddNodeTail((list*)o->ptr,ele);
             } else {
@@ -3556,7 +3655,7 @@ static robj *rdbLoadObject(int type, FILE *fp) {
             double *score = zmalloc(sizeof(double));
 
             if ((ele = rdbLoadStringObject(fp)) == NULL) return NULL;
-            tryObjectEncoding(ele);
+            ele = tryObjectEncoding(ele);
             if (rdbLoadDoubleValue(fp,score) == -1) return NULL;
             dictAdd(zs->dict,ele,score);
             zslInsert(zs->zsl,*score,ele);
@@ -3595,8 +3694,8 @@ static robj *rdbLoadObject(int type, FILE *fp) {
                 decrRefCount(key);
                 decrRefCount(val);
             } else {
-                tryObjectEncoding(key);
-                tryObjectEncoding(val);
+                key = tryObjectEncoding(key);
+                val = tryObjectEncoding(val);
                 dictAdd((dict*)o->ptr,key,val);
             }
         }
@@ -3751,7 +3850,7 @@ static void setnxCommand(redisClient *c) {
 
 static int getGenericCommand(redisClient *c) {
     robj *o;
-    
+
     if ((o = lookupKeyReadOrReply(c,c->argv[1],shared.nullbulk)) == NULL)
         return REDIS_OK;
 
@@ -3782,7 +3881,7 @@ static void getsetCommand(redisClient *c) {
 
 static void mgetCommand(redisClient *c) {
     int j;
-  
+
     addReplySds(c,sdscatprintf(sdsempty(),"*%d\r\n",c->argc-1));
     for (j = 1; j < c->argc; j++) {
         robj *o = lookupKeyRead(c->db,c->argv[j]);
@@ -3822,7 +3921,7 @@ static void msetGenericCommand(redisClient *c, int nx) {
     for (j = 1; j < c->argc; j += 2) {
         int retval;
 
-        tryObjectEncoding(c->argv[j+1]);
+        c->argv[j+1] = tryObjectEncoding(c->argv[j+1]);
         retval = dictAdd(c->db->dict,c->argv[j],c->argv[j+1]);
         if (retval == DICT_ERR) {
             dictReplace(c->db->dict,c->argv[j],c->argv[j+1]);
@@ -3849,7 +3948,7 @@ static void incrDecrCommand(redisClient *c, long long incr) {
     long long value;
     int retval;
     robj *o;
-    
+
     o = lookupKeyWrite(c->db,c->argv[1]);
     if (o == NULL) {
         value = 0;
@@ -3870,7 +3969,7 @@ static void incrDecrCommand(redisClient *c, long long incr) {
 
     value += incr;
     o = createObject(REDIS_STRING,sdscatprintf(sdsempty(),"%lld",value));
-    tryObjectEncoding(o);
+    o = tryObjectEncoding(o);
     retval = dictAdd(c->db->dict,c->argv[1],o);
     if (retval == DICT_ERR) {
         dictReplace(c->db->dict,c->argv[1],o);
@@ -3916,7 +4015,7 @@ static void appendCommand(redisClient *c) {
         totlen = stringObjectLen(c->argv[2]);
     } else {
         dictEntry *de;
-       
+
         de = dictFind(c->db->dict,c->argv[1]);
         assert(de != NULL);
 
@@ -4005,7 +4104,7 @@ static void existsCommand(redisClient *c) {
 
 static void selectCommand(redisClient *c) {
     int id = atoi(c->argv[1]->ptr);
-    
+
     if (selectDb(c,id) == REDIS_ERR) {
         addReplySds(c,sdsnew("-ERR invalid DB index\r\n"));
     } else {
@@ -4015,7 +4114,7 @@ static void selectCommand(redisClient *c) {
 
 static void randomkeyCommand(redisClient *c) {
     dictEntry *de;
-   
+
     while(1) {
         de = dictGetRandomKey(c->db->dict);
         if (!de || expireIfNeeded(c->db,dictGetEntryKey(de)) == 0) break;
@@ -4143,7 +4242,7 @@ static void shutdownCommand(redisClient *c) {
              * in the next cron() Redis will be notified that the background
              * saving aborted, handling special stuff like slaves pending for
              * synchronization... */
-            redisLog(REDIS_WARNING,"Error trying to save the DB, can't exit"); 
+            redisLog(REDIS_WARNING,"Error trying to save the DB, can't exit");
             addReplySds(c,
                 sdsnew("-ERR can't quit, problems saving the DB\r\n"));
         }
@@ -4287,7 +4386,7 @@ static void llenCommand(redisClient *c) {
 
     if ((o = lookupKeyReadOrReply(c,c->argv[1],shared.czero)) == NULL ||
         checkType(c,o,REDIS_LIST)) return;
-    
+
     l = o->ptr;
     addReplyUlong(c,listLength(l));
 }
@@ -4355,6 +4454,7 @@ static void popGenericCommand(redisClient *c, int where) {
         robj *ele = listNodeValue(ln);
         addReplyBulk(c,ele);
         listDelNode(list,ln);
+        if (listLength(list) == 0) deleteKey(c->db,c->argv[1]);
         server.dirty++;
     }
 }
@@ -4377,8 +4477,8 @@ static void lrangeCommand(redisClient *c) {
     listNode *ln;
     robj *ele;
 
-    if ((o = lookupKeyReadOrReply(c,c->argv[1],shared.nullmultibulk)) == NULL ||
-        checkType(c,o,REDIS_LIST)) return;
+    if ((o = lookupKeyReadOrReply(c,c->argv[1],shared.emptymultibulk)) == NULL
+         || checkType(c,o,REDIS_LIST)) return;
     list = o->ptr;
     llen = listLength(list);
 
@@ -4447,6 +4547,7 @@ static void ltrimCommand(redisClient *c) {
         ln = listLast(list);
         listDelNode(list,ln);
     }
+    if (listLength(list) == 0) deleteKey(c->db,c->argv[1]);
     server.dirty++;
     addReply(c,shared.ok);
 }
@@ -4480,6 +4581,7 @@ static void lremCommand(redisClient *c) {
         }
         ln = next;
     }
+    if (listLength(list) == 0) deleteKey(c->db,c->argv[1]);
     addReplySds(c,sdscatprintf(sdsempty(),":%d\r\n",removed));
 }
 
@@ -4539,6 +4641,7 @@ static void rpoplpushcommand(redisClient *c) {
 
         /* Finally remove the element from the source list */
         listDelNode(srclist,ln);
+        if (listLength(srclist) == 0) deleteKey(c->db,c->argv[1]);
         server.dirty++;
     }
 }
@@ -4577,6 +4680,7 @@ static void sremCommand(redisClient *c) {
     if (dictDelete(set->ptr,c->argv[2]) == DICT_OK) {
         server.dirty++;
         if (htNeedsResize(set->ptr)) dictResize(set->ptr);
+        if (dictSize((dict*)set->ptr) == 0) deleteKey(c->db,c->argv[1]);
         addReply(c,shared.cone);
     } else {
         addReply(c,shared.czero);
@@ -4606,6 +4710,8 @@ static void smoveCommand(redisClient *c) {
         addReply(c,shared.czero);
         return;
     }
+    if (dictSize((dict*)srcset->ptr) == 0 && srcset != dstset)
+        deleteKey(c->db,c->argv[1]);
     server.dirty++;
     /* Add the element to the destination set */
     if (!dstset) {
@@ -4636,7 +4742,7 @@ static void scardCommand(redisClient *c) {
 
     if ((o = lookupKeyReadOrReply(c,c->argv[1],shared.czero)) == NULL ||
         checkType(c,o,REDIS_SET)) return;
-    
+
     s = o->ptr;
     addReplyUlong(c,dictSize(s));
 }
@@ -4657,6 +4763,7 @@ static void spopCommand(redisClient *c) {
         addReplyBulk(c,ele);
         dictDelete(set->ptr,ele);
         if (htNeedsResize(set->ptr)) dictResize(set->ptr);
+        if (dictSize((dict*)set->ptr) == 0) deleteKey(c->db,c->argv[1]);
         server.dirty++;
     }
 }
@@ -4704,7 +4811,7 @@ static void sinterGenericCommand(redisClient *c, robj **setskeys, unsigned long
                     server.dirty++;
                 addReply(c,shared.czero);
             } else {
-                addReply(c,shared.nullmultibulk);
+                addReply(c,shared.emptymultibulk);
             }
             return;
         }
@@ -4758,18 +4865,20 @@ static void sinterGenericCommand(redisClient *c, robj **setskeys, unsigned long
     dictReleaseIterator(di);
 
     if (dstkey) {
-        /* Store the resulting set into the target */
+        /* Store the resulting set into the target, if the intersection
+         * is not an empty set. */
         deleteKey(c->db,dstkey);
-        dictAdd(c->db->dict,dstkey,dstset);
-        incrRefCount(dstkey);
-    }
-
-    if (!dstkey) {
-        lenobj->ptr = sdscatprintf(sdsempty(),"*%lu\r\n",cardinality);
-    } else {
-        addReplySds(c,sdscatprintf(sdsempty(),":%lu\r\n",
-            dictSize((dict*)dstset->ptr)));
+        if (dictSize((dict*)dstset->ptr) > 0) {
+            dictAdd(c->db->dict,dstkey,dstset);
+            incrRefCount(dstkey);
+            addReplyLong(c,dictSize((dict*)dstset->ptr));
+        } else {
+            decrRefCount(dstset);
+            addReply(c,shared.czero);
+        }
         server.dirty++;
+    } else {
+        lenobj->ptr = sdscatprintf(sdsempty(),"*%lu\r\n",cardinality);
     }
     zfree(dv);
 }
@@ -4842,7 +4951,8 @@ static void sunionDiffGenericCommand(redisClient *c, robj **setskeys, int setsnu
         }
         dictReleaseIterator(di);
 
-        if (op == REDIS_OP_DIFF && cardinality == 0) break; /* result set is empty */
+        /* result set is empty? Exit asap. */
+        if (op == REDIS_OP_DIFF && cardinality == 0) break;
     }
 
     /* Output the content of the resulting set, if not in STORE mode */
@@ -4856,20 +4966,19 @@ static void sunionDiffGenericCommand(redisClient *c, robj **setskeys, int setsnu
             addReplyBulk(c,ele);
         }
         dictReleaseIterator(di);
+        decrRefCount(dstset);
     } else {
         /* If we have a target key where to store the resulting set
          * create this key with the result set inside */
         deleteKey(c->db,dstkey);
-        dictAdd(c->db->dict,dstkey,dstset);
-        incrRefCount(dstkey);
-    }
-
-    /* Cleanup */
-    if (!dstkey) {
-        decrRefCount(dstset);
-    } else {
-        addReplySds(c,sdscatprintf(sdsempty(),":%lu\r\n",
-            dictSize((dict*)dstset->ptr)));
+        if (dictSize((dict*)dstset->ptr) > 0) {
+            dictAdd(c->db->dict,dstkey,dstset);
+            incrRefCount(dstkey);
+            addReplyLong(c,dictSize((dict*)dstset->ptr));
+        } else {
+            decrRefCount(dstset);
+            addReply(c,shared.czero);
+        }
         server.dirty++;
     }
     zfree(dv);
@@ -4924,7 +5033,7 @@ static zskiplistNode *zslCreateNode(int level, double score, robj *obj) {
 static zskiplist *zslCreate(void) {
     int j;
     zskiplist *zsl;
-    
+
     zsl = zmalloc(sizeof(*zsl));
     zsl->level = 1;
     zsl->length = 0;
@@ -4966,7 +5075,7 @@ static int zslRandomLevel(void) {
     int level = 1;
     while ((random()&0xFFFF) < (ZSKIPLIST_P * 0xFFFF))
         level += 1;
-    return level;
+    return (level<ZSKIPLIST_MAXLEVEL) ? level : ZSKIPLIST_MAXLEVEL;
 }
 
 static void zslInsert(zskiplist *zsl, double score, robj *obj) {
@@ -5257,7 +5366,7 @@ static void zaddGenericCommand(redisClient *c, robj *key, robj *ele, double scor
     } else {
         dictEntry *de;
         double *oldscore;
-        
+
         /* case 2: Score update operation */
         de = dictFind(zs->dict,ele);
         redisAssert(de != NULL);
@@ -5321,6 +5430,7 @@ static void zremCommand(redisClient *c) {
     /* Delete from the hash table */
     dictDelete(zs->dict,c->argv[2]);
     if (htNeedsResize(zs->dict)) dictResize(zs->dict);
+    if (dictSize(zs->dict) == 0) deleteKey(c->db,c->argv[1]);
     server.dirty++;
     addReply(c,shared.cone);
 }
@@ -5338,6 +5448,7 @@ static void zremrangebyscoreCommand(redisClient *c) {
     zs = zsetobj->ptr;
     deleted = zslDeleteRangeByScore(zs->zsl,min,max,zs->dict);
     if (htNeedsResize(zs->dict)) dictResize(zs->dict);
+    if (dictSize(zs->dict) == 0) deleteKey(c->db,c->argv[1]);
     server.dirty += deleted;
     addReplyLong(c,deleted);
 }
@@ -5372,6 +5483,7 @@ static void zremrangebyrankCommand(redisClient *c) {
      * use 1-based rank */
     deleted = zslDeleteRangeByRank(zs->zsl,start+1,end+1,zs->dict);
     if (htNeedsResize(zs->dict)) dictResize(zs->dict);
+    if (dictSize(zs->dict) == 0) deleteKey(c->db,c->argv[1]);
     server.dirty += deleted;
     addReplyLong(c, deleted);
 }
@@ -5555,11 +5667,15 @@ static void zunionInterGenericCommand(redisClient *c, robj *dstkey, int op) {
     }
 
     deleteKey(c->db,dstkey);
-    dictAdd(c->db->dict,dstkey,dstobj);
-    incrRefCount(dstkey);
-
-    addReplyLong(c, dstzset->zsl->length);
-    server.dirty++;
+    if (dstzset->zsl->length) {
+        dictAdd(c->db->dict,dstkey,dstobj);
+        incrRefCount(dstkey);
+        addReplyLong(c, dstzset->zsl->length);
+        server.dirty++;
+    } else {
+        decrRefCount(dstobj);
+        addReply(c, shared.czero);
+    }
     zfree(src);
 }
 
@@ -5590,8 +5706,8 @@ static void zrangeGenericCommand(redisClient *c, int reverse) {
         return;
     }
 
-    if ((o = lookupKeyReadOrReply(c,c->argv[1],shared.nullmultibulk)) == NULL ||
-        checkType(c,o,REDIS_ZSET)) return;
+    if ((o = lookupKeyReadOrReply(c,c->argv[1],shared.emptymultibulk)) == NULL
+         || checkType(c,o,REDIS_ZSET)) return;
     zsetobj = o->ptr;
     zsl = zsetobj->zsl;
     llen = zsl->length;
@@ -5697,7 +5813,7 @@ static void genericZrangebyscoreCommand(redisClient *c, int justcount) {
     /* Ok, lookup the key and get the range */
     o = lookupKeyRead(c->db,c->argv[1]);
     if (o == NULL) {
-        addReply(c,justcount ? shared.czero : shared.nullmultibulk);
+        addReply(c,justcount ? shared.czero : shared.emptymultibulk);
     } else {
         if (o->type != REDIS_ZSET) {
             addReply(c,shared.wrongtypeerr);
@@ -5872,13 +5988,11 @@ static void hsetCommand(redisClient *c) {
         decrRefCount(valobj);
         o->ptr = zm;
 
-        /* And here there is the second check for hash conversion...
-         * we want to do it only if the operation was not just an update as
-         * zipmapLen() is O(N). */
-        if (!update && zipmapLen(zm) > server.hash_max_zipmap_entries)
+        /* And here there is the second check for hash conversion. */
+        if (zipmapLen(zm) > server.hash_max_zipmap_entries)
             convertToRealHash(o);
     } else {
-        tryObjectEncoding(c->argv[2]);
+        c->argv[2] = tryObjectEncoding(c->argv[2]);
         /* note that c->argv[3] is already encoded, as the latest arg
          * of a bulk command is always integer encoded if possible. */
         if (dictReplace(o->ptr,c->argv[2],c->argv[3])) {
@@ -5892,6 +6006,139 @@ static void hsetCommand(redisClient *c) {
     addReplySds(c,sdscatprintf(sdsempty(),":%d\r\n",update == 0));
 }
 
+static void hmsetCommand(redisClient *c) {
+    int i;
+    robj *o, *key, *val;
+
+    if ((c->argc % 2) == 1) {
+        addReplySds(c,sdsnew("-ERR wrong number of arguments for HMSET\r\n"));
+        return;
+    }
+
+    if ((o = lookupKeyWrite(c->db,c->argv[1])) == NULL) {
+        o = createHashObject();
+        dictAdd(c->db->dict,c->argv[1],o);
+        incrRefCount(c->argv[1]);
+    } else {
+        if (o->type != REDIS_HASH) {
+            addReply(c,shared.wrongtypeerr);
+            return;
+        }
+    }
+
+    /* We want to convert the zipmap into an hash table right now if the
+     * entry to be added is too big. */
+    if (o->encoding == REDIS_ENCODING_ZIPMAP) {
+        for (i = 2; i < c->argc; i+=2) {
+            if ((c->argv[i]->encoding == REDIS_ENCODING_RAW &&
+                  sdslen(c->argv[i]->ptr) > server.hash_max_zipmap_value) ||
+                (c->argv[i+1]->encoding == REDIS_ENCODING_RAW &&
+                  sdslen(c->argv[i+1]->ptr) > server.hash_max_zipmap_value)) {
+                convertToRealHash(o);
+                break;
+            }
+        }
+    }
+
+    if (o->encoding == REDIS_ENCODING_ZIPMAP) {
+        unsigned char *zm = o->ptr;
+
+        for (i = 2; i < c->argc; i+=2) {
+            key = getDecodedObject(c->argv[i]);
+            val = getDecodedObject(c->argv[i+1]);
+            zm = zipmapSet(zm,key->ptr,sdslen(key->ptr),
+                              val->ptr,sdslen(val->ptr),NULL);
+            decrRefCount(key);
+            decrRefCount(val);
+            o->ptr = zm;
+        }
+
+        /* And here there is the second check for hash conversion. */
+        if (zipmapLen(zm) > server.hash_max_zipmap_entries)
+            convertToRealHash(o);
+    } else {
+        for (i = 2; i < c->argc; i+=2) {
+            key = tryObjectEncoding(c->argv[i]);
+            val = tryObjectEncoding(c->argv[i+1]);
+            if (dictReplace(o->ptr,key,val)) {
+                incrRefCount(key);
+            }
+            incrRefCount(val);
+        }
+    }
+
+    addReply(c, shared.ok);
+}
+
+static void hincrbyCommand(redisClient *c) {
+    long long value = 0, incr = 0;
+    robj *o = lookupKeyWrite(c->db,c->argv[1]);
+
+    if (o == NULL) {
+        o = createHashObject();
+        dictAdd(c->db->dict,c->argv[1],o);
+        incrRefCount(c->argv[1]);
+    } else {
+        if (o->type != REDIS_HASH) {
+            addReply(c,shared.wrongtypeerr);
+            return;
+        }
+    }
+
+    incr = strtoll(c->argv[3]->ptr, NULL, 10);
+    if (o->encoding == REDIS_ENCODING_ZIPMAP) {
+        unsigned char *zm = o->ptr;
+        unsigned char *zval;
+        unsigned int zvlen;
+
+        /* Find value if already present in hash */
+        if (zipmapGet(zm,c->argv[2]->ptr,sdslen(c->argv[2]->ptr),
+            &zval,&zvlen)) {
+            /* strtoll needs the char* to have a trailing \0, but
+             * the zipmap doesn't include them. */
+            sds szval = sdsnewlen(zval, zvlen);
+            value = strtoll(szval,NULL,10);
+            sdsfree(szval);
+        }
+
+        value += incr;
+        sds svalue = sdscatprintf(sdsempty(),"%lld",value);
+        zm = zipmapSet(zm,c->argv[2]->ptr,sdslen(c->argv[2]->ptr),
+            (unsigned char*)svalue,sdslen(svalue),NULL);
+        sdsfree(svalue);
+        o->ptr = zm;
+
+        /* Check if the zipmap needs to be converted. */
+        if (zipmapLen(zm) > server.hash_max_zipmap_entries)
+            convertToRealHash(o);
+    } else {
+        robj *hval;
+        dictEntry *de;
+
+        /* Find value if already present in hash */
+        de = dictFind(o->ptr,c->argv[2]);
+        if (de != NULL) {
+            hval = dictGetEntryVal(de);
+            if (hval->encoding == REDIS_ENCODING_RAW)
+                value = strtoll(hval->ptr,NULL,10);
+            else if (hval->encoding == REDIS_ENCODING_INT)
+                value = (long)hval->ptr;
+            else
+                redisAssert(1 != 1);
+        }
+
+        value += incr;
+        hval = createObject(REDIS_STRING,sdscatprintf(sdsempty(),"%lld",value));
+        hval = tryObjectEncoding(hval);
+        if (dictReplace(o->ptr,c->argv[2],hval)) {
+            incrRefCount(c->argv[2]);
+        }
+    }
+
+    server.dirty++;
+    addReplyLongLong(c, value);
+}
+
 static void hgetCommand(redisClient *c) {
     robj *o;
 
@@ -5938,12 +6185,20 @@ static void hdelCommand(redisClient *c) {
         checkType(c,o,REDIS_HASH)) return;
 
     if (o->encoding == REDIS_ENCODING_ZIPMAP) {
+        robj *field = getDecodedObject(c->argv[2]);
+
         o->ptr = zipmapDel((unsigned char*) o->ptr,
-            (unsigned char*) c->argv[2]->ptr,
-            sdslen(c->argv[2]->ptr), &deleted);
+            (unsigned char*) field->ptr,
+            sdslen(field->ptr), &deleted);
+        decrRefCount(field);
+        if (zipmapLen((unsigned char*) o->ptr) == 0)
+            deleteKey(c->db,c->argv[1]);
     } else {
         deleted = dictDelete((dict*)o->ptr,c->argv[2]) == DICT_OK;
+        if (htNeedsResize(o->ptr)) dictResize(o->ptr);
+        if (dictSize((dict*)o->ptr) == 0) deleteKey(c->db,c->argv[1]);
     }
+    if (deleted) server.dirty++;
     addReply(c,deleted ? shared.cone : shared.czero);
 }
 
@@ -5965,7 +6220,7 @@ static void genericHgetallCommand(redisClient *c, int flags) {
     robj *o, *lenobj;
     unsigned long count = 0;
 
-    if ((o = lookupKeyReadOrReply(c,c->argv[1],shared.nullmultibulk)) == NULL
+    if ((o = lookupKeyReadOrReply(c,c->argv[1],shared.emptymultibulk)) == NULL
         || checkType(c,o,REDIS_HASH)) return;
 
     lenobj = createObject(REDIS_STRING,NULL);
@@ -6059,8 +6314,8 @@ static void convertToRealHash(robj *o) {
 
         keyobj = createStringObject((char*)key,klen);
         valobj = createStringObject((char*)val,vlen);
-        tryObjectEncoding(keyobj);
-        tryObjectEncoding(valobj);
+        keyobj = tryObjectEncoding(keyobj);
+        valobj = tryObjectEncoding(valobj);
         dictAdd(dict,keyobj,valobj);
     }
     o->encoding = REDIS_ENCODING_HT;
@@ -6080,6 +6335,10 @@ static void flushdbCommand(redisClient *c) {
 static void flushallCommand(redisClient *c) {
     server.dirty += emptyDb();
     addReply(c,shared.ok);
+    if (server.bgsavechildpid != -1) {
+        kill(server.bgsavechildpid,SIGKILL);
+        rdbRemoveTempFile(server.bgsavechildpid);
+    }
     rdbSave(server.dbfilename);
     server.dirty++;
 }
@@ -6201,7 +6460,7 @@ static void sortCommand(redisClient *c) {
     /* Lookup the key to sort. It must be of the right types */
     sortval = lookupKeyRead(c->db,c->argv[1]);
     if (sortval == NULL) {
-        addReply(c,shared.nullmultibulk);
+        addReply(c,shared.emptymultibulk);
         return;
     }
     if (sortval->type != REDIS_SET && sortval->type != REDIS_LIST &&
@@ -6471,9 +6730,6 @@ static sds genRedisInfoString(void) {
     int j;
     char hmem[64];
 
-    server.hash_max_zipmap_entries = REDIS_HASH_MAX_ZIPMAP_ENTRIES;
-    server.hash_max_zipmap_value = REDIS_HASH_MAX_ZIPMAP_VALUE;
-  
     bytesToHuman(hmem,zmalloc_used_memory());
     info = sdscatprintf(sdsempty(),
         "redis_version:%s\r\n"
@@ -6493,8 +6749,11 @@ static sds genRedisInfoString(void) {
         "bgrewriteaof_in_progress:%d\r\n"
         "total_connections_received:%lld\r\n"
         "total_commands_processed:%lld\r\n"
+        "expired_keys:%lld\r\n"
         "hash_max_zipmap_entries:%ld\r\n"
         "hash_max_zipmap_value:%ld\r\n"
+        "pubsub_channels:%ld\r\n"
+        "pubsub_patterns:%u\r\n"
         "vm_enabled:%d\r\n"
         "role:%s\r\n"
         ,REDIS_VERSION,
@@ -6514,8 +6773,11 @@ static sds genRedisInfoString(void) {
         server.bgrewritechildpid != -1,
         server.stat_numconnections,
         server.stat_numcommands,
+        server.stat_expiredkeys,
         server.hash_max_zipmap_entries,
         server.hash_max_zipmap_value,
+        dictSize(server.pubsub_channels),
+        listLength(server.pubsub_patterns),
         server.vm_enabled != 0,
         server.masterhost == NULL ? "master" : "slave"
     );
@@ -6637,6 +6899,7 @@ static int expireIfNeeded(redisDb *db, robj *key) {
 
     /* Delete the key */
     dictDelete(db->expires,key);
+    server.stat_expiredkeys++;
     return dictDelete(db->dict,key) == DICT_OK;
 }
 
@@ -6649,6 +6912,7 @@ static int deleteIfVolatile(redisDb *db, robj *key) {
 
     /* Delete the key */
     server.dirty++;
+    server.stat_expiredkeys++;
     dictDelete(db->expires,key);
     return dictDelete(db->dict,key) == DICT_OK;
 }
@@ -6926,7 +7190,7 @@ static void blockingPopGenericCommand(redisClient *c, int where) {
                      * 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;
@@ -7163,7 +7427,7 @@ static void updateSlavesWaitingBgsave(int bgsaveerr) {
             slave->replstate = REDIS_REPL_WAIT_BGSAVE_END;
         } else if (slave->replstate == REDIS_REPL_WAIT_BGSAVE_END) {
             struct redis_stat buf;
-           
+
             if (bgsaveerr != REDIS_OK) {
                 freeClient(slave);
                 redisLog(REDIS_WARNING,"SYNC failed. BGSAVE child returned an error");
@@ -7561,14 +7825,9 @@ int loadAppendOnlyFile(char *filename) {
             redisLog(REDIS_WARNING,"Unknown command '%s' reading the append only file", argv[0]->ptr);
             exit(1);
         }
-        /* Try object sharing and encoding */
-        if (server.shareobjects) {
-            int j;
-            for(j = 1; j < argc; j++)
-                argv[j] = tryObjectSharing(argv[j]);
-        }
+        /* Try object encoding */
         if (cmd->flags & REDIS_CMD_BULK)
-            tryObjectEncoding(argv[argc-1]);
+            argv[argc-1] = tryObjectEncoding(argv[argc-1]);
         /* Run the command in the context of a fake client */
         fakeClient->argc = argc;
         fakeClient->argv = argv;
@@ -7825,7 +8084,7 @@ static int rewriteAppendOnlyFile(char *filename) {
     fflush(fp);
     fsync(fileno(fp));
     fclose(fp);
-    
+
     /* Use RENAME to make sure the DB file is changed atomically only
      * if the generate DB file is ok. */
     if (rename(tmpfile,filename) == -1) {
@@ -7884,6 +8143,7 @@ static int rewriteAppendOnlyFileBackground(void) {
         redisLog(REDIS_NOTICE,
             "Background append only file rewriting started by pid %d",childpid);
         server.bgrewritechildpid = childpid;
+        updateDictResizePolicy();
         /* We set appendseldb to -1 in order to force the next call to the
          * feedAppendOnlyFile() to issue a SELECT command, so the differences
          * accumulated by the parent into server.bgrewritebuf will start
@@ -7942,7 +8202,7 @@ static void aofRemoveTempFile(pid_t childpid) {
 static void expandVmSwapFilename(void) {
     char *p = strstr(server.vm_swap_file,"%p");
     sds new;
-    
+
     if (!p) return;
     new = sdsempty();
     *p = '\0';
@@ -8067,7 +8327,7 @@ static int vmFreePage(off_t page) {
 }
 
 /* Find N contiguous free pages storing the first page of the cluster in *first.
- * Returns REDIS_OK if it was able to find N contiguous pages, otherwise 
+ * Returns REDIS_OK if it was able to find N contiguous pages, otherwise
  * REDIS_ERR is returned.
  *
  * This function uses a simple algorithm: we try to allocate
@@ -8078,7 +8338,7 @@ static int vmFreePage(off_t page) {
  * we try to find less populated places doing a forward jump of
  * REDIS_VM_MAX_RANDOM_JUMP, then we start scanning again a few pages
  * without hurry, and then we jump again and so forth...
- * 
+ *
  * This function can be improved using a free list to avoid to guess
  * too much, since we could collect data about freed pages.
  *
@@ -8305,6 +8565,38 @@ static double computeObjectSwappability(robj *o) {
             if (z) asize += sizeof(zskiplistNode)*dictSize(d);
         }
         break;
+    case REDIS_HASH:
+        if (o->encoding == REDIS_ENCODING_ZIPMAP) {
+            unsigned char *p = zipmapRewind((unsigned char*)o->ptr);
+            unsigned int len = zipmapLen((unsigned char*)o->ptr);
+            unsigned int klen, vlen;
+            unsigned char *key, *val;
+
+            if ((p = zipmapNext(p,&key,&klen,&val,&vlen)) == NULL) {
+                klen = 0;
+                vlen = 0;
+            }
+            asize = len*(klen+vlen+3);
+        } else if (o->encoding == REDIS_ENCODING_HT) {
+            d = o->ptr;
+            asize = sizeof(dict)+(sizeof(struct dictEntry*)*dictSlots(d));
+            if (dictSize(d)) {
+                long elesize;
+                robj *ele;
+
+                de = dictGetRandomKey(d);
+                ele = dictGetEntryKey(de);
+                elesize = (ele->encoding == REDIS_ENCODING_RAW) ?
+                                (sizeof(*o)+sdslen(ele->ptr)) :
+                                sizeof(*o);
+                ele = dictGetEntryVal(de);
+                elesize = (ele->encoding == REDIS_ENCODING_RAW) ?
+                                (sizeof(*o)+sdslen(ele->ptr)) :
+                                sizeof(*o);
+                asize += (sizeof(struct dictEntry)+elesize)*dictSize(d);
+            }
+        }
+        break;
     }
     return (double)age*log(1+asize);
 }
@@ -8419,7 +8711,10 @@ static void freeIOJob(iojob *j) {
         j->type == REDIS_IOJOB_DO_SWAP ||
         j->type == REDIS_IOJOB_LOAD) && j->val != NULL)
         decrRefCount(j->val);
-    decrRefCount(j->key);
+    /* We don't decrRefCount the j->key field as we did't incremented
+     * the count creating IO Jobs. This is because the key field here is
+     * just used as an indentifier and if a key is removed the Job should
+     * never be touched again. */
     zfree(j);
 }
 
@@ -8592,7 +8887,7 @@ again:
             iojob *job = ln->value;
 
             if (job->canceled) continue; /* Skip this, already canceled. */
-            if (compareStringObjects(job->key,o) == 0) {
+            if (job->key == o) {
                 redisLog(REDIS_DEBUG,"*** CANCELED %p (%s) (type %d) (LIST ID %d)\n",
                     (void*)job, (char*)o->ptr, job->type, i);
                 /* Mark the pages as free since the swap didn't happened
@@ -8697,7 +8992,7 @@ static void *IOThreadEntryPoint(void *arg) {
         listDelNode(server.io_processing,ln);
         listAddNodeTail(server.io_processed,j);
         unlockThreadedIO();
-        
+
         /* Signal the main thread there is new stuff to process */
         assert(write(server.io_ready_pipe_write,"x",1) == 1);
     }
@@ -8707,13 +9002,18 @@ static void *IOThreadEntryPoint(void *arg) {
 static void spawnIOThread(void) {
     pthread_t thread;
     sigset_t mask, omask;
+    int err;
 
     sigemptyset(&mask);
     sigaddset(&mask,SIGCHLD);
     sigaddset(&mask,SIGHUP);
     sigaddset(&mask,SIGPIPE);
     pthread_sigmask(SIG_SETMASK, &mask, &omask);
-    pthread_create(&thread,&server.io_threads_attr,IOThreadEntryPoint,NULL);
+    while ((err = pthread_create(&thread,&server.io_threads_attr,IOThreadEntryPoint,NULL)) != 0) {
+        redisLog(REDIS_WARNING,"Unable to spawn an I/O thread: %s",
+            strerror(err));
+        usleep(1000000);
+    }
     pthread_sigmask(SIG_SETMASK, &omask, NULL);
     server.io_active_threads++;
 }
@@ -8770,14 +9070,14 @@ static void queueIOJob(iojob *j) {
 
 static int vmSwapObjectThreaded(robj *key, robj *val, redisDb *db) {
     iojob *j;
-    
+
     assert(key->storage == REDIS_VM_MEMORY);
     assert(key->refcount == 1);
 
     j = zmalloc(sizeof(*j));
     j->type = REDIS_IOJOB_PREPARE_SWAP;
     j->db = db;
-    j->key = dupStringObject(key);
+    j->key = key;
     j->val = val;
     incrRefCount(val);
     j->canceled = 0;
@@ -8814,7 +9114,7 @@ static int waitForSwappedKey(redisClient *c, robj *key) {
         vmCancelThreadedIOJob(o);
         return 0;
     }
-    
+
     /* OK: the key is either swapped, or being loaded just now. */
 
     /* Add the key to the list of keys this client is waiting for.
@@ -8845,7 +9145,7 @@ static int waitForSwappedKey(redisClient *c, robj *key) {
         j = zmalloc(sizeof(*j));
         j->type = REDIS_IOJOB_LOAD;
         j->db = c->db;
-        j->key = dupStringObject(key);
+        j->key = o;
         j->key->vtype = o->vtype;
         j->page = o->vm.page;
         j->val = NULL;
@@ -8858,6 +9158,15 @@ static int waitForSwappedKey(redisClient *c, robj *key) {
     return 1;
 }
 
+/* Preload keys needed for the ZUNION and ZINTER commands. */
+static void zunionInterBlockClientOnSwappedKeys(redisClient *c) {
+    int i, num;
+    num = atoi(c->argv[2]->ptr);
+    for (i = 0; i < num; i++) {
+        waitForSwappedKey(c,c->argv[3+i]);
+    }
+}
+
 /* Is this client attempting to run a command against swapped keys?
  * If so, block it ASAP, load the keys in background, then resume it.
  *
@@ -8871,11 +9180,16 @@ static int waitForSwappedKey(redisClient *c, robj *key) {
 static int blockClientOnSwappedKeys(struct redisCommand *cmd, redisClient *c) {
     int j, last;
 
-    if (cmd->vm_firstkey == 0) return 0;
-    last = cmd->vm_lastkey;
-    if (last < 0) last = c->argc+last;
-    for (j = cmd->vm_firstkey; j <= last; j += cmd->vm_keystep)
-        waitForSwappedKey(c,c->argv[j]);
+    if (cmd->vm_preload_proc != NULL) {
+        cmd->vm_preload_proc(c);
+    } else {
+        if (cmd->vm_firstkey == 0) return 0;
+        last = cmd->vm_lastkey;
+        if (last < 0) last = c->argc+last;
+        for (j = cmd->vm_firstkey; j <= last; j += cmd->vm_keystep)
+            waitForSwappedKey(c,c->argv[j]);
+    }
+
     /* If the client was blocked for at least one key, mark it as blocked. */
     if (listLength(c->io_keys)) {
         c->flags |= REDIS_IO_WAIT;
@@ -8945,6 +9259,353 @@ static void handleClientsBlockedOnSwappedKey(redisDb *db, robj *key) {
     }
 }
 
+/* =========================== Remote Configuration ========================= */
+
+static void configSetCommand(redisClient *c) {
+    robj *o = getDecodedObject(c->argv[3]);
+    if (!strcasecmp(c->argv[2]->ptr,"dbfilename")) {
+        zfree(server.dbfilename);
+        server.dbfilename = zstrdup(o->ptr);
+    } else if (!strcasecmp(c->argv[2]->ptr,"requirepass")) {
+        zfree(server.requirepass);
+        server.requirepass = zstrdup(o->ptr);
+    } else if (!strcasecmp(c->argv[2]->ptr,"masterauth")) {
+        zfree(server.masterauth);
+        server.masterauth = zstrdup(o->ptr);
+    } else if (!strcasecmp(c->argv[2]->ptr,"maxmemory")) {
+        server.maxmemory = strtoll(o->ptr, NULL, 10);
+    } else {
+        addReplySds(c,sdscatprintf(sdsempty(),
+            "-ERR not supported CONFIG parameter %s\r\n",
+            (char*)c->argv[2]->ptr));
+        decrRefCount(o);
+        return;
+    }
+    decrRefCount(o);
+    addReply(c,shared.ok);
+}
+
+static void configGetCommand(redisClient *c) {
+    robj *o = getDecodedObject(c->argv[2]);
+    robj *lenobj = createObject(REDIS_STRING,NULL);
+    char *pattern = o->ptr;
+    int matches = 0;
+
+    addReply(c,lenobj);
+    decrRefCount(lenobj);
+
+    if (stringmatch(pattern,"dbfilename",0)) {
+        addReplyBulkCString(c,"dbfilename");
+        addReplyBulkCString(c,server.dbfilename);
+        matches++;
+    }
+    if (stringmatch(pattern,"requirepass",0)) {
+        addReplyBulkCString(c,"requirepass");
+        addReplyBulkCString(c,server.requirepass);
+        matches++;
+    }
+    if (stringmatch(pattern,"masterauth",0)) {
+        addReplyBulkCString(c,"masterauth");
+        addReplyBulkCString(c,server.masterauth);
+        matches++;
+    }
+    if (stringmatch(pattern,"maxmemory",0)) {
+        char buf[128];
+
+        snprintf(buf,128,"%llu\n",server.maxmemory);
+        addReplyBulkCString(c,"maxmemory");
+        addReplyBulkCString(c,buf);
+        matches++;
+    }
+    decrRefCount(o);
+    lenobj->ptr = sdscatprintf(sdsempty(),"*%d\r\n",matches*2);
+}
+
+static void configCommand(redisClient *c) {
+    if (!strcasecmp(c->argv[1]->ptr,"set")) {
+        if (c->argc != 4) goto badarity;
+        configSetCommand(c);
+    } else if (!strcasecmp(c->argv[1]->ptr,"get")) {
+        if (c->argc != 3) goto badarity;
+        configGetCommand(c);
+    } else if (!strcasecmp(c->argv[1]->ptr,"resetstat")) {
+        if (c->argc != 2) goto badarity;
+        server.stat_numcommands = 0;
+        server.stat_numconnections = 0;
+        server.stat_expiredkeys = 0;
+        server.stat_starttime = time(NULL);
+        addReply(c,shared.ok);
+    } else {
+        addReplySds(c,sdscatprintf(sdsempty(),
+            "-ERR CONFIG subcommand must be one of GET, SET, RESETSTAT\r\n"));
+    }
+    return;
+
+badarity:
+    addReplySds(c,sdscatprintf(sdsempty(),
+        "-ERR Wrong number of arguments for CONFIG %s\r\n",
+        (char*) c->argv[1]->ptr));
+}
+
+/* =========================== Pubsub implementation ======================== */
+
+static void freePubsubPattern(void *p) {
+    pubsubPattern *pat = p;
+
+    decrRefCount(pat->pattern);
+    zfree(pat);
+}
+
+static int listMatchPubsubPattern(void *a, void *b) {
+    pubsubPattern *pa = a, *pb = b;
+
+    return (pa->client == pb->client) &&
+           (compareStringObjects(pa->pattern,pb->pattern) == 0);
+}
+
+/* Subscribe a client to a channel. Returns 1 if the operation succeeded, or
+ * 0 if the client was already subscribed to that channel. */
+static int pubsubSubscribeChannel(redisClient *c, robj *channel) {
+    struct dictEntry *de;
+    list *clients = NULL;
+    int retval = 0;
+
+    /* Add the channel to the client -> channels hash table */
+    if (dictAdd(c->pubsub_channels,channel,NULL) == DICT_OK) {
+        retval = 1;
+        incrRefCount(channel);
+        /* Add the client to the channel -> list of clients hash table */
+        de = dictFind(server.pubsub_channels,channel);
+        if (de == NULL) {
+            clients = listCreate();
+            dictAdd(server.pubsub_channels,channel,clients);
+            incrRefCount(channel);
+        } else {
+            clients = dictGetEntryVal(de);
+        }
+        listAddNodeTail(clients,c);
+    }
+    /* Notify the client */
+    addReply(c,shared.mbulk3);
+    addReply(c,shared.subscribebulk);
+    addReplyBulk(c,channel);
+    addReplyLong(c,dictSize(c->pubsub_channels)+listLength(c->pubsub_patterns));
+    return retval;
+}
+
+/* Unsubscribe a client from a channel. Returns 1 if the operation succeeded, or
+ * 0 if the client was not subscribed to the specified channel. */
+static int pubsubUnsubscribeChannel(redisClient *c, robj *channel, int notify) {
+    struct dictEntry *de;
+    list *clients;
+    listNode *ln;
+    int retval = 0;
+
+    /* Remove the channel from the client -> channels hash table */
+    incrRefCount(channel); /* channel may be just a pointer to the same object
+                            we have in the hash tables. Protect it... */
+    if (dictDelete(c->pubsub_channels,channel) == DICT_OK) {
+        retval = 1;
+        /* Remove the client from the channel -> clients list hash table */
+        de = dictFind(server.pubsub_channels,channel);
+        assert(de != NULL);
+        clients = dictGetEntryVal(de);
+        ln = listSearchKey(clients,c);
+        assert(ln != NULL);
+        listDelNode(clients,ln);
+        if (listLength(clients) == 0) {
+            /* Free the list and associated hash entry at all if this was
+             * the latest client, so that it will be possible to abuse
+             * Redis PUBSUB creating millions of channels. */
+            dictDelete(server.pubsub_channels,channel);
+        }
+    }
+    /* Notify the client */
+    if (notify) {
+        addReply(c,shared.mbulk3);
+        addReply(c,shared.unsubscribebulk);
+        addReplyBulk(c,channel);
+        addReplyLong(c,dictSize(c->pubsub_channels)+
+                       listLength(c->pubsub_patterns));
+
+    }
+    decrRefCount(channel); /* it is finally safe to release it */
+    return retval;
+}
+
+/* Subscribe a client to a pattern. Returns 1 if the operation succeeded, or 0 if the clinet was already subscribed to that pattern. */
+static int pubsubSubscribePattern(redisClient *c, robj *pattern) {
+    int retval = 0;
+
+    if (listSearchKey(c->pubsub_patterns,pattern) == NULL) {
+        retval = 1;
+        pubsubPattern *pat;
+        listAddNodeTail(c->pubsub_patterns,pattern);
+        incrRefCount(pattern);
+        pat = zmalloc(sizeof(*pat));
+        pat->pattern = getDecodedObject(pattern);
+        pat->client = c;
+        listAddNodeTail(server.pubsub_patterns,pat);
+    }
+    /* Notify the client */
+    addReply(c,shared.mbulk3);
+    addReply(c,shared.psubscribebulk);
+    addReplyBulk(c,pattern);
+    addReplyLong(c,dictSize(c->pubsub_channels)+listLength(c->pubsub_patterns));
+    return retval;
+}
+
+/* Unsubscribe a client from a channel. Returns 1 if the operation succeeded, or
+ * 0 if the client was not subscribed to the specified channel. */
+static 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 */
+    if ((ln = listSearchKey(c->pubsub_patterns,pattern)) != NULL) {
+        retval = 1;
+        listDelNode(c->pubsub_patterns,ln);
+        pat.client = c;
+        pat.pattern = pattern;
+        ln = listSearchKey(server.pubsub_patterns,&pat);
+        listDelNode(server.pubsub_patterns,ln);
+    }
+    /* Notify the client */
+    if (notify) {
+        addReply(c,shared.mbulk3);
+        addReply(c,shared.punsubscribebulk);
+        addReplyBulk(c,pattern);
+        addReplyLong(c,dictSize(c->pubsub_channels)+
+                       listLength(c->pubsub_patterns));
+    }
+    decrRefCount(pattern);
+    return retval;
+}
+
+/* Unsubscribe from all the channels. Return the number of channels the
+ * client was subscribed from. */
+static int pubsubUnsubscribeAllChannels(redisClient *c, int notify) {
+    dictIterator *di = dictGetIterator(c->pubsub_channels);
+    dictEntry *de;
+    int count = 0;
+
+    while((de = dictNext(di)) != NULL) {
+        robj *channel = dictGetEntryKey(de);
+
+        count += pubsubUnsubscribeChannel(c,channel,notify);
+    }
+    dictReleaseIterator(di);
+    return count;
+}
+
+/* Unsubscribe from all the patterns. Return the number of patterns the
+ * client was subscribed from. */
+static int pubsubUnsubscribeAllPatterns(redisClient *c, int notify) {
+    listNode *ln;
+    listIter li;
+    int count = 0;
+
+    listRewind(c->pubsub_patterns,&li);
+    while ((ln = listNext(&li)) != NULL) {
+        robj *pattern = ln->value;
+
+        count += pubsubUnsubscribePattern(c,pattern,notify);
+    }
+    return count;
+}
+
+/* Publish a message */
+static int pubsubPublishMessage(robj *channel, robj *message) {
+    int receivers = 0;
+    struct dictEntry *de;
+    listNode *ln;
+    listIter li;
+
+    /* Send to clients listening for that channel */
+    de = dictFind(server.pubsub_channels,channel);
+    if (de) {
+        list *list = dictGetEntryVal(de);
+        listNode *ln;
+        listIter li;
+
+        listRewind(list,&li);
+        while ((ln = listNext(&li)) != NULL) {
+            redisClient *c = ln->value;
+
+            addReply(c,shared.mbulk3);
+            addReply(c,shared.messagebulk);
+            addReplyBulk(c,channel);
+            addReplyBulk(c,message);
+            receivers++;
+        }
+    }
+    /* Send to clients listening to matching channels */
+    if (listLength(server.pubsub_patterns)) {
+        listRewind(server.pubsub_patterns,&li);
+        channel = getDecodedObject(channel);
+        while ((ln = listNext(&li)) != NULL) {
+            pubsubPattern *pat = ln->value;
+
+            if (stringmatchlen((char*)pat->pattern->ptr,
+                                sdslen(pat->pattern->ptr),
+                                (char*)channel->ptr,
+                                sdslen(channel->ptr),0)) {
+                addReply(pat->client,shared.mbulk3);
+                addReply(pat->client,shared.messagebulk);
+                addReplyBulk(pat->client,channel);
+                addReplyBulk(pat->client,message);
+                receivers++;
+            }
+        }
+        decrRefCount(channel);
+    }
+    return receivers;
+}
+
+static void subscribeCommand(redisClient *c) {
+    int j;
+
+    for (j = 1; j < c->argc; j++)
+        pubsubSubscribeChannel(c,c->argv[j]);
+}
+
+static void unsubscribeCommand(redisClient *c) {
+    if (c->argc == 1) {
+        pubsubUnsubscribeAllChannels(c,1);
+        return;
+    } else {
+        int j;
+
+        for (j = 1; j < c->argc; j++)
+            pubsubUnsubscribeChannel(c,c->argv[j],1);
+    }
+}
+
+static void psubscribeCommand(redisClient *c) {
+    int j;
+
+    for (j = 1; j < c->argc; j++)
+        pubsubSubscribePattern(c,c->argv[j]);
+}
+
+static void punsubscribeCommand(redisClient *c) {
+    if (c->argc == 1) {
+        pubsubUnsubscribeAllPatterns(c,1);
+        return;
+    } else {
+        int j;
+
+        for (j = 1; j < c->argc; j++)
+            pubsubUnsubscribePattern(c,c->argv[j],1);
+    }
+}
+
+static void publishCommand(redisClient *c) {
+    int receivers = pubsubPublishMessage(c->argv[1],c->argv[2]);
+    addReplyLong(c,receivers);
+}
+
 /* ================================= Debugging ============================== */
 
 static void debugCommand(redisClient *c) {
@@ -9003,6 +9664,9 @@ static void debugCommand(redisClient *c) {
                 (void*)key, key->refcount, (unsigned long long) key->vm.page,
                 (unsigned long long) key->vm.usedpages));
         }
+    } else if (!strcasecmp(c->argv[1]->ptr,"swapin") && c->argc == 3) {
+        lookupKeyRead(c->db,c->argv[2]);
+        addReply(c,shared.ok);
     } else if (!strcasecmp(c->argv[1]->ptr,"swapout") && c->argc == 3) {
         dictEntry *de = dictFind(c->db->dict,c->argv[2]);
         robj *key, *val;
@@ -9034,7 +9698,7 @@ static void debugCommand(redisClient *c) {
         }
     } else {
         addReplySds(c,sdsnew(
-            "-ERR Syntax error, try DEBUG [SEGFAULT|OBJECT <key>|SWAPOUT <key>|RELOAD]\r\n"));
+            "-ERR Syntax error, try DEBUG [SEGFAULT|OBJECT <key>|SWAPIN <key>|SWAPOUT <key>|RELOAD]\r\n"));
     }
 }
 
@@ -9095,16 +9759,29 @@ static void daemonize(void) {
     }
 }
 
+static void version() {
+    printf("Redis server version %s\n", REDIS_VERSION);
+    exit(0);
+}
+
+static void usage() {
+    fprintf(stderr,"Usage: ./redis-server [/path/to/redis.conf]\n");
+    fprintf(stderr,"       ./redis-server - (read config from stdin)\n");
+    exit(1);
+}
+
 int main(int argc, char **argv) {
     time_t start;
 
     initServerConfig();
     if (argc == 2) {
+        if (strcmp(argv[1], "-v") == 0 ||
+            strcmp(argv[1], "--version") == 0) version();
+        if (strcmp(argv[1], "--help") == 0) usage();
         resetServerSaveParams();
         loadServerConfig(argv[1]);
-    } else if (argc > 2) {
-        fprintf(stderr,"Usage: ./redis-server [/path/to/redis.conf]\n");
-        exit(1);
+    } else if ((argc > 2)) {
+        usage();
     } else {
         redisLog(REDIS_WARNING,"Warning: no config file specified, using the default config. In order to specify a config file use 'redis-server /path/to/redis.conf'");
     }
@@ -9150,7 +9827,7 @@ static void *getMcontextEip(ucontext_t *uc) {
     return (void*) uc->uc_mcontext->__ss.__rip;
   #else
     return (void*) uc->uc_mcontext->__ss.__eip;
-  #endif 
+  #endif
 #elif defined(__i386__) || defined(__X86_64__) || defined(__x86_64__)
     return (void*) uc->uc_mcontext.gregs[REG_EIP]; /* Linux 32/64 bit */
 #elif defined(__ia64__) /* Linux IA64 */
@@ -9175,7 +9852,7 @@ static void segvHandler(int sig, siginfo_t *info, void *secret) {
     redisLog(REDIS_WARNING, "%s",infostring);
     /* It's not safe to sdsfree() the returned string under memory
      * corruption conditions. Let it leak as we are going to abort */
-    
+
     trace_size = backtrace(trace, 100);
     /* overwrite sigaction with caller's address */
     if (getMcontextEip(uc) != NULL) {