]> git.saurik.com Git - redis.git/blobdiff - redis.c
Fixed the same problem in ZREVRANK
[redis.git] / redis.c
diff --git a/redis.c b/redis.c
index f7779cebe42ae1f7eb2846d0bca4d582945f8e50..c43f7fd9605a38da950234097c41544b7e5006ef 100644 (file)
--- a/redis.c
+++ b/redis.c
@@ -75,6 +75,7 @@
 #include "zmalloc.h" /* total memory usage aware version of malloc/free */
 #include "lzf.h"    /* LZF compression library */
 #include "pqsort.h" /* Partial qsort for SORT+LIMIT */
+#include "zipmap.h"
 
 /* Error codes */
 #define REDIS_OK                0
 #define REDIS_ZSET 3
 #define REDIS_HASH 4
 
-/* Objects encoding */
+/* Objects encoding. Some kind of objects like Strings and Hashes can be
+ * internally represented in multiple ways. The 'encoding' field of the object
+ * is set to one of this fields for this object. */
 #define REDIS_ENCODING_RAW 0    /* Raw representation */
 #define REDIS_ENCODING_INT 1    /* Encoded as integer */
+#define REDIS_ENCODING_ZIPMAP 2 /* Encoded as zipmap */
+#define REDIS_ENCODING_HT 3     /* Encoded as an hash table */
+
+static char* strencoding[] = {
+    "raw", "int", "zipmap", "hashtable"
+};
 
 /* Object types only used for dumping to disk */
 #define REDIS_EXPIRETIME 253
 #define APPENDFSYNC_ALWAYS 1
 #define APPENDFSYNC_EVERYSEC 2
 
+/* Hashes related defaults */
+#define REDIS_HASH_MAX_ZIPMAP_ENTRIES 64
+#define REDIS_HASH_MAX_ZIPMAP_VALUE 512
+
 /* We can print the stacktrace, so our assert is defined this way: */
 #define redisAssert(_e) ((_e)?(void)0 : (_redisAssert(#_e,__FILE__,__LINE__),_exit(1)))
 static void _redisAssert(char *estr, char *file, int line);
@@ -386,6 +399,9 @@ struct redisServer {
     off_t vm_page_size;
     off_t vm_pages;
     unsigned long long vm_max_memory;
+    /* Hashes config */
+    size_t hash_max_zipmap_entries;
+    size_t hash_max_zipmap_value;
     /* Virtual memory state */
     FILE *vm_fp;
     int vm_fd;
@@ -578,6 +594,7 @@ static void readQueryFromClient(aeEventLoop *el, int fd, void *privdata, int mas
 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 void authCommand(redisClient *c);
 static void pingCommand(redisClient *c);
@@ -661,7 +678,13 @@ static void brpopCommand(redisClient *c);
 static void appendCommand(redisClient *c);
 static void substrCommand(redisClient *c);
 static void zrankCommand(redisClient *c);
+static void zrevrankCommand(redisClient *c);
+static void hsetCommand(redisClient *c);
+static void hgetCommand(redisClient *c);
+static void hdelCommand(redisClient *c);
 static void zremrangebyrankCommand(redisClient *c);
+static void zunionCommand(redisClient *c);
+static void zinterCommand(redisClient *c);
 
 /*================================= Globals ================================= */
 
@@ -710,13 +733,19 @@ static struct redisCommand cmdTable[] = {
     {"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_INLINE,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},
     {"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},
@@ -1013,7 +1042,7 @@ static dictType zsetDictType = {
 };
 
 /* Db->dict */
-static dictType hashDictType = {
+static dictType dbDictType = {
     dictObjHash,                /* hash function */
     NULL,                       /* key dup */
     NULL,                       /* val dup */
@@ -1032,6 +1061,16 @@ static dictType keyptrDictType = {
     NULL                       /* val destructor */
 };
 
+/* Hash type hash table (note that small hashes are represented with zimpaps) */
+static dictType hashDictType = {
+    dictEncObjHash,             /* hash function */
+    NULL,                       /* key dup */
+    NULL,                       /* val dup */
+    dictEncObjKeyCompare,       /* key compare */
+    dictRedisObjectDestructor,  /* key destructor */
+    dictRedisObjectDestructor   /* val destructor */
+};
+
 /* Keylist hash table type has unencoded redis objects as keys and
  * lists as values. It's used for blocking operations (BLPOP) and to
  * map swapped keys to a list of clients waiting for this keys to be loaded. */
@@ -1448,6 +1487,8 @@ static void initServerConfig() {
     server.vm_max_memory = 1024LL*1024*1024*1; /* 1 GB of RAM */
     server.vm_max_threads = 4;
     server.vm_blocked_clients = 0;
+    server.hash_max_zipmap_entries = REDIS_HASH_MAX_ZIPMAP_ENTRIES;
+    server.hash_max_zipmap_value = REDIS_HASH_MAX_ZIPMAP_VALUE;
 
     resetServerSaveParams();
 
@@ -1495,7 +1536,7 @@ static void initServer() {
         exit(1);
     }
     for (j = 0; j < server.dbnum; j++) {
-        server.db[j].dict = dictCreate(&hashDictType,NULL);
+        server.db[j].dict = dictCreate(&dbDictType,NULL);
         server.db[j].expires = dictCreate(&keyptrDictType,NULL);
         server.db[j].blockingkeys = dictCreate(&keylistDictType,NULL);
         if (server.vm_enabled)
@@ -1708,6 +1749,12 @@ static void loadServerConfig(char *filename) {
             server.vm_pages = strtoll(argv[1], NULL, 10);
         } else if (!strcasecmp(argv[0],"vm-max-threads") && argc == 2) {
             server.vm_max_threads = strtoll(argv[1], NULL, 10);
+        } else if (!strcasecmp(argv[0],"hash-max-zipmap-entries") && argc == 2){
+            server.hash_max_zipmap_entries = strtol(argv[1], NULL, 10);
+        } else if (!strcasecmp(argv[0],"hash-max-zipmap-value") && argc == 2){
+            server.hash_max_zipmap_value = strtol(argv[1], NULL, 10);
+        } else if (!strcasecmp(argv[0],"vm-max-threads") && argc == 2) {
+            server.vm_max_threads = strtoll(argv[1], NULL, 10);
         } else {
             err = "Bad directive or wrong number of arguments"; goto loaderr;
         }
@@ -2545,6 +2592,16 @@ static robj *createSetObject(void) {
     return createObject(REDIS_SET,d);
 }
 
+static robj *createHashObject(void) {
+    /* All the Hashes start as zipmaps. Will be automatically converted
+     * into hash tables if there are enough elements or big elements
+     * inside. */
+    unsigned char *zm = zipmapNew();
+    robj *o = createObject(REDIS_HASH,zm);
+    o->encoding = REDIS_ENCODING_ZIPMAP;
+    return o;
+}
+
 static robj *createZsetObject(void) {
     zset *zs = zmalloc(sizeof(*zs));
 
@@ -2576,7 +2633,17 @@ static void freeZsetObject(robj *o) {
 }
 
 static void freeHashObject(robj *o) {
-    dictRelease((dict*) o->ptr);
+    switch (o->encoding) {
+    case REDIS_ENCODING_HT:
+        dictRelease((dict*) o->ptr);
+        break;
+    case REDIS_ENCODING_ZIPMAP:
+        zfree(o->ptr);
+        break;
+    default:
+        redisAssert(0);
+        break;
+    }
 }
 
 static void incrRefCount(robj *o) {
@@ -2881,7 +2948,7 @@ static int rdbSaveLen(FILE *fp, uint32_t len) {
 /* String objects in the form "2391" "-100" without any space and with a
  * range of values that can fit in an 8, 16 or 32 bit signed value can be
  * encoded as integers to save space */
-static int rdbTryIntegerEncoding(sds s, unsigned char *enc) {
+static int rdbTryIntegerEncoding(char *s, size_t len, unsigned char *enc) {
     long long value;
     char *endptr, buf[32];
 
@@ -2892,7 +2959,7 @@ static int rdbTryIntegerEncoding(sds s, unsigned char *enc) {
 
     /* If the number converted back into a string is not identical
      * then it's not possible to encode the string as integer */
-    if (strlen(buf) != sdslen(s) || memcmp(buf,s,sdslen(s))) return 0;
+    if (strlen(buf) != len || memcmp(buf,s,len)) return 0;
 
     /* Finally check if it fits in our ranges */
     if (value >= -(1<<7) && value <= (1<<7)-1) {
@@ -2916,16 +2983,16 @@ static int rdbTryIntegerEncoding(sds s, unsigned char *enc) {
     }
 }
 
-static int rdbSaveLzfStringObject(FILE *fp, robj *obj) {
-    unsigned int comprlen, outlen;
+static int rdbSaveLzfStringObject(FILE *fp, unsigned char *s, size_t len) {
+    size_t comprlen, outlen;
     unsigned char byte;
     void *out;
 
     /* We require at least four bytes compression for this to be worth it */
-    outlen = sdslen(obj->ptr)-4;
-    if (outlen <= 0) return 0;
+    if (len <= 4) return 0;
+    outlen = len-4;
     if ((out = zmalloc(outlen+1)) == NULL) return 0;
-    comprlen = lzf_compress(obj->ptr, sdslen(obj->ptr), out, outlen);
+    comprlen = lzf_compress(s, len, out, outlen);
     if (comprlen == 0) {
         zfree(out);
         return 0;
@@ -2934,7 +3001,7 @@ static int rdbSaveLzfStringObject(FILE *fp, robj *obj) {
     byte = (REDIS_RDB_ENCVAL<<6)|REDIS_RDB_ENC_LZF;
     if (fwrite(&byte,1,1,fp) == 0) goto writeerr;
     if (rdbSaveLen(fp,comprlen) == -1) goto writeerr;
-    if (rdbSaveLen(fp,sdslen(obj->ptr)) == -1) goto writeerr;
+    if (rdbSaveLen(fp,len) == -1) goto writeerr;
     if (fwrite(out,comprlen,1,fp) == 0) goto writeerr;
     zfree(out);
     return comprlen;
@@ -2946,16 +3013,13 @@ writeerr:
 
 /* Save a string objet as [len][data] on disk. If the object is a string
  * representation of an integer value we try to safe it in a special form */
-static int rdbSaveStringObjectRaw(FILE *fp, robj *obj) {
-    size_t len;
+static int rdbSaveRawString(FILE *fp, unsigned char *s, size_t len) {
     int enclen;
 
-    len = sdslen(obj->ptr);
-
     /* Try integer encoding */
     if (len <= 11) {
         unsigned char buf[5];
-        if ((enclen = rdbTryIntegerEncoding(obj->ptr,buf)) > 0) {
+        if ((enclen = rdbTryIntegerEncoding((char*)s,len,buf)) > 0) {
             if (fwrite(buf,enclen,1,fp) == 0) return -1;
             return 0;
         }
@@ -2966,7 +3030,7 @@ static int rdbSaveStringObjectRaw(FILE *fp, robj *obj) {
     if (server.rdbcompression && len > 20) {
         int retval;
 
-        retval = rdbSaveLzfStringObject(fp,obj);
+        retval = rdbSaveLzfStringObject(fp,s,len);
         if (retval == -1) return -1;
         if (retval > 0) return 0;
         /* retval == 0 means data can't be compressed, save the old way */
@@ -2974,7 +3038,7 @@ static int rdbSaveStringObjectRaw(FILE *fp, robj *obj) {
 
     /* Store verbatim */
     if (rdbSaveLen(fp,len) == -1) return -1;
-    if (len && fwrite(obj->ptr,len,1,fp) == 0) return -1;
+    if (len && fwrite(s,len,1,fp) == 0) return -1;
     return 0;
 }
 
@@ -2989,10 +3053,10 @@ static int rdbSaveStringObject(FILE *fp, robj *obj) {
      * this in order to avoid bugs) */
     if (obj->encoding != REDIS_ENCODING_RAW) {
         obj = getDecodedObject(obj);
-        retval = rdbSaveStringObjectRaw(fp,obj);
+        retval = rdbSaveRawString(fp,obj->ptr,sdslen(obj->ptr));
         decrRefCount(obj);
     } else {
-        retval = rdbSaveStringObjectRaw(fp,obj);
+        retval = rdbSaveRawString(fp,obj->ptr,sdslen(obj->ptr));
     }
     return retval;
 }
@@ -3070,6 +3134,33 @@ static int rdbSaveObject(FILE *fp, robj *o) {
             if (rdbSaveDoubleValue(fp,*score) == -1) return -1;
         }
         dictReleaseIterator(di);
+    } else if (o->type == REDIS_HASH) {
+        /* Save a hash value */
+        if (o->encoding == REDIS_ENCODING_ZIPMAP) {
+            unsigned char *p = zipmapRewind(o->ptr);
+            unsigned int count = zipmapLen(o->ptr);
+            unsigned char *key, *val;
+            unsigned int klen, vlen;
+
+            if (rdbSaveLen(fp,count) == -1) return -1;
+            while((p = zipmapNext(p,&key,&klen,&val,&vlen)) != NULL) {
+                if (rdbSaveRawString(fp,key,klen) == -1) return -1;
+                if (rdbSaveRawString(fp,val,vlen) == -1) return -1;
+            }
+        } else {
+            dictIterator *di = dictGetIterator(o->ptr);
+            dictEntry *de;
+
+            if (rdbSaveLen(fp,dictSize((dict*)o->ptr)) == -1) return -1;
+            while((de = dictNext(di)) != NULL) {
+                robj *key = dictGetEntryKey(de);
+                robj *val = dictGetEntryVal(de);
+
+                if (rdbSaveStringObject(fp,key) == -1) return -1;
+                if (rdbSaveStringObject(fp,val) == -1) return -1;
+            }
+            dictReleaseIterator(di);
+        }
     } else {
         redisAssert(0 != 0);
     }
@@ -3366,6 +3457,7 @@ static int rdbLoadDoubleValue(FILE *fp, double *val) {
 static robj *rdbLoadObject(int type, FILE *fp) {
     robj *o;
 
+    redisLog(REDIS_DEBUG,"LOADING OBJECT %d (at %d)\n",type,ftell(fp));
     if (type == REDIS_STRING) {
         /* Read string value */
         if ((o = rdbLoadStringObject(fp)) == NULL) return NULL;
@@ -3394,7 +3486,7 @@ static robj *rdbLoadObject(int type, FILE *fp) {
         }
     } else if (type == REDIS_ZSET) {
         /* Read list/set value */
-        uint32_t zsetlen;
+        size_t zsetlen;
         zset *zs;
 
         if ((zsetlen = rdbLoadLen(fp,NULL)) == REDIS_RDB_LENERR) return NULL;
@@ -3412,6 +3504,46 @@ static robj *rdbLoadObject(int type, FILE *fp) {
             zslInsert(zs->zsl,*score,ele);
             incrRefCount(ele); /* added to skiplist */
         }
+    } else if (type == REDIS_HASH) {
+        size_t hashlen;
+
+        if ((hashlen = rdbLoadLen(fp,NULL)) == REDIS_RDB_LENERR) return NULL;
+        o = createHashObject();
+        /* Too many entries? Use an hash table. */
+        if (hashlen > server.hash_max_zipmap_entries)
+            convertToRealHash(o);
+        /* Load every key/value, then set it into the zipmap or hash
+         * table, as needed. */
+        while(hashlen--) {
+            robj *key, *val;
+
+            if ((key = rdbLoadStringObject(fp)) == NULL) return NULL;
+            if ((val = rdbLoadStringObject(fp)) == NULL) return NULL;
+            /* If we are using a zipmap and there are too big values
+             * the object is converted to real hash table encoding. */
+            if (o->encoding != REDIS_ENCODING_HT &&
+               (sdslen(key->ptr) > server.hash_max_zipmap_value ||
+                sdslen(val->ptr) > server.hash_max_zipmap_value))
+            {
+                    convertToRealHash(o);
+            }
+
+            if (o->encoding == REDIS_ENCODING_ZIPMAP) {
+                unsigned char *zm = o->ptr;
+
+                zm = zipmapSet(zm,key->ptr,sdslen(key->ptr),
+                                  val->ptr,sdslen(val->ptr),NULL);
+                o->ptr = zm;
+                decrRefCount(key);
+                decrRefCount(val);
+            } else {
+                tryObjectEncoding(key);
+                tryObjectEncoding(val);
+                dictAdd((dict*)o->ptr,key,val);
+                incrRefCount(key);
+                incrRefCount(val);
+            }
+        }
     } else {
         redisAssert(0 != 0);
     }
@@ -3803,7 +3935,7 @@ static void substrCommand(redisClient *c) {
             rangelen = (end-start)+1;
 
             /* Return the result */
-            addReplySds(c,sdscatprintf(sdsempty(),"$%lu\r\n",rangelen));
+            addReplySds(c,sdscatprintf(sdsempty(),"$%zu\r\n",rangelen));
             range = sdsnewlen((char*)o->ptr+start,rangelen);
             addReplySds(c,range);
             addReply(c,shared.crlf);
@@ -3919,7 +4051,8 @@ static void typeCommand(redisClient *c) {
         case REDIS_LIST: type = "+list"; break;
         case REDIS_SET: type = "+set"; break;
         case REDIS_ZSET: type = "+zset"; break;
-        default: type = "unknown"; break;
+        case REDIS_HASH: type = "+hash"; break;
+        default: type = "+unknown"; break;
         }
     }
     addReplySds(c,sdsnew(type));
@@ -4715,6 +4848,7 @@ static void sinterstoreCommand(redisClient *c) {
 
 #define REDIS_OP_UNION 0
 #define REDIS_OP_DIFF 1
+#define REDIS_OP_INTER 2
 
 static void sunionDiffGenericCommand(redisClient *c, robj **setskeys, int setsnum, robj *dstkey, int op) {
     dict **dv = zmalloc(sizeof(dict*)*setsnum);
@@ -4958,6 +5092,31 @@ static void zslInsert(zskiplist *zsl, double score, robj *obj) {
     zsl->length++;
 }
 
+/* Internal function used by zslDelete, zslDeleteByScore and zslDeleteByRank */
+void zslDeleteNode(zskiplist *zsl, zskiplistNode *x, zskiplistNode **update) {
+    int i;
+    for (i = 0; i < zsl->level; i++) {
+        if (update[i]->forward[i] == x) {
+            if (i > 0) {
+                update[i]->span[i-1] += x->span[i-1] - 1;
+            }
+            update[i]->forward[i] = x->forward[i];
+        } else {
+            /* invariant: i > 0, because update[0]->forward[0]
+             * is always equal to x */
+            update[i]->span[i-1] -= 1;
+        }
+    }
+    if (x->forward[0]) {
+        x->forward[0]->backward = x->backward;
+    } else {
+        zsl->tail = x->backward;
+    }
+    while(zsl->level > 1 && zsl->header->forward[zsl->level-1] == NULL)
+        zsl->level--;
+    zsl->length--;
+}
+
 /* Delete an element with matching score/object from the skiplist. */
 static int zslDelete(zskiplist *zsl, double score, robj *obj) {
     zskiplistNode *update[ZSKIPLIST_MAXLEVEL], *x;
@@ -4976,27 +5135,8 @@ static int zslDelete(zskiplist *zsl, double score, robj *obj) {
      * is to find the element with both the right score and object. */
     x = x->forward[0];
     if (x && score == x->score && compareStringObjects(x->obj,obj) == 0) {
-        for (i = 0; i < zsl->level; i++) {
-            if (update[i]->forward[i] == x) {
-                if (i > 0) {
-                    update[i]->span[i-1] += x->span[i-1] - 1;
-                }
-                update[i]->forward[i] = x->forward[i];
-            } else {
-                /* invariant: i > 0, because update[0]->forward[0]
-                 * is always equal to x */
-                update[i]->span[i-1] -= 1;
-            }
-        }
-        if (x->forward[0]) {
-            x->forward[0]->backward = x->backward;
-        } else {
-            zsl->tail = x->backward;
-        }
+        zslDeleteNode(zsl, x, update);
         zslFreeNode(x);
-        while(zsl->level > 1 && zsl->header->forward[zsl->level-1] == NULL)
-            zsl->level--;
-        zsl->length--;
         return 1;
     } else {
         return 0; /* not found */
@@ -5023,31 +5163,10 @@ static unsigned long zslDeleteRangeByScore(zskiplist *zsl, double min, double ma
      * is to find the element with both the right score and object. */
     x = x->forward[0];
     while (x && x->score <= max) {
-        zskiplistNode *next;
-
-        for (i = 0; i < zsl->level; i++) {
-            if (update[i]->forward[i] == x) {
-                if (i > 0) {
-                    update[i]->span[i-1] += x->span[i-1] - 1;
-                }
-                update[i]->forward[i] = x->forward[i];
-            } else {
-                /* invariant: i > 0, because update[0]->forward[0]
-                 * is always equal to x */
-                update[i]->span[i-1] -= 1;
-            }
-        }
-        if (x->forward[0]) {
-            x->forward[0]->backward = x->backward;
-        } else {
-            zsl->tail = x->backward;
-        }
-        next = x->forward[0];
+        zskiplistNode *next = x->forward[0];
+        zslDeleteNode(zsl, x, update);
         dictDelete(dict,x->obj);
         zslFreeNode(x);
-        while(zsl->level > 1 && zsl->header->forward[zsl->level-1] == NULL)
-            zsl->level--;
-        zsl->length--;
         removed++;
         x = next;
     }
@@ -5073,31 +5192,10 @@ static unsigned long zslDeleteRangeByRank(zskiplist *zsl, unsigned int start, un
     traversed++;
     x = x->forward[0];
     while (x && traversed <= end) {
-        zskiplistNode *next;
-
-        for (i = 0; i < zsl->level; i++) {
-            if (update[i]->forward[i] == x) {
-                if (i > 0) {
-                    update[i]->span[i-1] += x->span[i-1] - 1;
-                }
-                update[i]->forward[i] = x->forward[i];
-            } else {
-                /* invariant: i > 0, because update[0]->forward[0]
-                 * is always equal to x */
-                update[i]->span[i-1] -= 1;
-            }
-        }
-        if (x->forward[0]) {
-            x->forward[0]->backward = x->backward;
-        } else {
-            zsl->tail = x->backward;
-        }
-        next = x->forward[0];
+        zskiplistNode *next = x->forward[0];
+        zslDeleteNode(zsl, x, update);
         dictDelete(dict,x->obj);
         zslFreeNode(x);
-        while(zsl->level > 1 && zsl->header->forward[zsl->level-1] == NULL)
-            zsl->level--;
-        zsl->length--;
         removed++;
         traversed++;
         x = next;
@@ -5365,6 +5463,171 @@ static void zremrangebyrankCommand(redisClient *c) {
     }
 }
 
+typedef struct {
+    dict *dict;
+    double weight;
+} zsetopsrc;
+
+static int qsortCompareZsetopsrcByCardinality(const void *s1, const void *s2) {
+    zsetopsrc *d1 = (void*) s1, *d2 = (void*) s2;
+    unsigned long size1, size2;
+    size1 = d1->dict ? dictSize(d1->dict) : 0;
+    size2 = d2->dict ? dictSize(d2->dict) : 0;
+    return size1 - size2;
+}
+
+static void zunionInterGenericCommand(redisClient *c, robj *dstkey, int op) {
+    int i, j, zsetnum;
+    zsetopsrc *src;
+    robj *dstobj;
+    zset *dstzset;
+    dictIterator *di;
+    dictEntry *de;
+
+    /* expect zsetnum input keys to be given */
+    zsetnum = atoi(c->argv[2]->ptr);
+    if (zsetnum < 1) {
+        addReplySds(c,sdsnew("-ERR at least 1 input key is needed for ZUNION/ZINTER\r\n"));
+        return;
+    }
+
+    /* test if the expected number of keys would overflow */
+    if (3+zsetnum > c->argc) {
+        addReply(c,shared.syntaxerr);
+        return;
+    }
+
+    /* read keys to be used for input */
+    src = zmalloc(sizeof(zsetopsrc) * zsetnum);
+    for (i = 0, j = 3; i < zsetnum; i++, j++) {
+        robj *zsetobj = lookupKeyWrite(c->db,c->argv[j]);
+        if (!zsetobj) {
+            src[i].dict = NULL;
+        } else {
+            if (zsetobj->type != REDIS_ZSET) {
+                zfree(src);
+                addReply(c,shared.wrongtypeerr);
+                return;
+            }
+            src[i].dict = ((zset*)zsetobj->ptr)->dict;
+        }
+
+        /* default all weights to 1 */
+        src[i].weight = 1.0;
+    }
+
+    /* parse optional extra arguments */
+    if (j < c->argc) {
+        int remaining = c->argc-j;
+
+        while (remaining) {
+            if (!strcasecmp(c->argv[j]->ptr,"weights")) {
+                j++; remaining--;
+                if (remaining < zsetnum) {
+                    zfree(src);
+                    addReplySds(c,sdsnew("-ERR not enough weights for ZUNION/ZINTER\r\n"));
+                    return;
+                }
+                for (i = 0; i < zsetnum; i++, j++, remaining--) {
+                    src[i].weight = strtod(c->argv[j]->ptr, NULL);
+                }
+            } else {
+                zfree(src);
+                addReply(c,shared.syntaxerr);
+                return;
+            }
+        }
+    }
+
+    dstobj = createZsetObject();
+    dstzset = dstobj->ptr;
+
+    if (op == REDIS_OP_INTER) {
+        /* sort sets from the smallest to largest, this will improve our
+         * algorithm's performance */
+        qsort(src,zsetnum,sizeof(zsetopsrc), qsortCompareZsetopsrcByCardinality);
+
+        /* skip going over all entries if the smallest zset is NULL or empty */
+        if (src[0].dict && dictSize(src[0].dict) > 0) {
+            /* precondition: as src[0].dict is non-empty and the zsets are ordered
+             * from small to large, all src[i > 0].dict are non-empty too */
+            di = dictGetIterator(src[0].dict);
+            while((de = dictNext(di)) != NULL) {
+                double *score = zmalloc(sizeof(double));
+                *score = 0.0;
+
+                for (j = 0; j < zsetnum; j++) {
+                    dictEntry *other = (j == 0) ? de : dictFind(src[j].dict,dictGetEntryKey(de));
+                    if (other) {
+                        *score = *score + src[j].weight * (*(double*)dictGetEntryVal(other));
+                    } else {
+                        break;
+                    }
+                }
+
+                /* skip entry when not present in every source dict */
+                if (j != zsetnum) {
+                    zfree(score);
+                } else {
+                    robj *o = dictGetEntryKey(de);
+                    dictAdd(dstzset->dict,o,score);
+                    incrRefCount(o); /* added to dictionary */
+                    zslInsert(dstzset->zsl,*score,o);
+                    incrRefCount(o); /* added to skiplist */
+                }
+            }
+            dictReleaseIterator(di);
+        }
+    } else if (op == REDIS_OP_UNION) {
+        for (i = 0; i < zsetnum; i++) {
+            if (!src[i].dict) continue;
+
+            di = dictGetIterator(src[i].dict);
+            while((de = dictNext(di)) != NULL) {
+                /* skip key when already processed */
+                if (dictFind(dstzset->dict,dictGetEntryKey(de)) != NULL) continue;
+
+                double *score = zmalloc(sizeof(double));
+                *score = 0.0;
+                for (j = 0; j < zsetnum; j++) {
+                    if (!src[j].dict) continue;
+
+                    dictEntry *other = (i == j) ? de : dictFind(src[j].dict,dictGetEntryKey(de));
+                    if (other) {
+                        *score = *score + src[j].weight * (*(double*)dictGetEntryVal(other));
+                    }
+                }
+
+                robj *o = dictGetEntryKey(de);
+                dictAdd(dstzset->dict,o,score);
+                incrRefCount(o); /* added to dictionary */
+                zslInsert(dstzset->zsl,*score,o);
+                incrRefCount(o); /* added to skiplist */
+            }
+            dictReleaseIterator(di);
+        }
+    } else {
+        /* unknown operator */
+        redisAssert(op == REDIS_OP_INTER || op == REDIS_OP_UNION);
+    }
+
+    deleteKey(c->db,dstkey);
+    dictAdd(c->db->dict,dstkey,dstobj);
+    incrRefCount(dstkey);
+
+    addReplyLong(c, dstzset->zsl->length);
+    server.dirty++;
+    zfree(src);
+}
+
+static void zunionCommand(redisClient *c) {
+    zunionInterGenericCommand(c,c->argv[1], REDIS_OP_UNION);
+}
+
+static void zinterCommand(redisClient *c) {
+    zunionInterGenericCommand(c,c->argv[1], REDIS_OP_INTER);
+}
+
 static void zrangeGenericCommand(redisClient *c, int reverse) {
     robj *o;
     int start = atoi(c->argv[2]->ptr);
@@ -5611,7 +5874,7 @@ static void zscoreCommand(redisClient *c) {
     }
 }
 
-static void zrankCommand(redisClient *c) {
+static void zrankGenericCommand(redisClient *c, int reverse) {
     robj *o;
     o = lookupKeyRead(c->db,c->argv[1]);
     if (o == NULL) {
@@ -5635,13 +5898,172 @@ static void zrankCommand(redisClient *c) {
         double *score = dictGetEntryVal(de);
         rank = zslGetRank(zsl, *score, c->argv[2]);
         if (rank) {
-            addReplyLong(c, rank-1);
+            if (reverse) {
+                addReplyLong(c, zsl->length - rank);
+            } else {
+                addReplyLong(c, rank-1);
+            }
         } else {
             addReply(c,shared.nullbulk);
         }
     }
 }
 
+static void zrankCommand(redisClient *c) {
+    zrankGenericCommand(c, 0);
+}
+
+static void zrevrankCommand(redisClient *c) {
+    zrankGenericCommand(c, 1);
+}
+
+/* =================================== Hashes =============================== */
+static void hsetCommand(redisClient *c) {
+    int update = 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;
+        }
+    }
+    /* We want to convert the zipmap into an hash table right now if the
+     * entry to be added is too big. Note that we check if the object
+     * is integer encoded before to try fetching the length in the test below.
+     * This is because integers are small, but currently stringObjectLen()
+     * performs a slow conversion: not worth it. */
+    if (o->encoding == REDIS_ENCODING_ZIPMAP &&
+        ((c->argv[2]->encoding == REDIS_ENCODING_RAW &&
+          sdslen(c->argv[2]->ptr) > server.hash_max_zipmap_value) ||
+         (c->argv[3]->encoding == REDIS_ENCODING_RAW &&
+          sdslen(c->argv[3]->ptr) > server.hash_max_zipmap_value)))
+    {
+        convertToRealHash(o);
+    }
+
+    if (o->encoding == REDIS_ENCODING_ZIPMAP) {
+        unsigned char *zm = o->ptr;
+        robj *valobj = getDecodedObject(c->argv[3]);
+
+        zm = zipmapSet(zm,c->argv[2]->ptr,sdslen(c->argv[2]->ptr),
+            valobj->ptr,sdslen(valobj->ptr),&update);
+        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)
+            convertToRealHash(o);
+    } else {
+        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 (dictAdd(o->ptr,c->argv[2],c->argv[3]) == DICT_OK) {
+            incrRefCount(c->argv[2]);
+        } else {
+            update = 1;
+        }
+        incrRefCount(c->argv[3]);
+    }
+    server.dirty++;
+    addReplySds(c,sdscatprintf(sdsempty(),":%d\r\n",update == 0));
+}
+
+static void hgetCommand(redisClient *c) {
+    robj *o = lookupKeyRead(c->db,c->argv[1]);
+
+    if (o == NULL) {
+        addReply(c,shared.nullbulk);
+        return;
+    } else {
+        if (o->type != REDIS_HASH) {
+            addReply(c,shared.wrongtypeerr);
+            return;
+        }
+
+        if (o->encoding == REDIS_ENCODING_ZIPMAP) {
+            unsigned char *zm = o->ptr;
+            unsigned char *val;
+            unsigned int vlen;
+
+            if (zipmapGet(zm,c->argv[2]->ptr,sdslen(c->argv[2]->ptr), &val,&vlen)) {
+                addReplySds(c,sdscatprintf(sdsempty(),"$%u\r\n", vlen));
+                addReplySds(c,sdsnewlen(val,vlen));
+                addReply(c,shared.crlf);
+                return;
+            } else {
+                addReply(c,shared.nullbulk);
+                return;
+            }
+        } else {
+            struct dictEntry *de;
+
+            de = dictFind(o->ptr,c->argv[2]);
+            if (de == NULL) {
+                addReply(c,shared.nullbulk);
+            } else {
+                robj *e = dictGetEntryVal(de);
+
+                addReplyBulkLen(c,e);
+                addReply(c,e);
+                addReply(c,shared.crlf);
+            }
+        }
+    }
+}
+
+static void hdelCommand(redisClient *c) {
+    robj *o = lookupKeyRead(c->db,c->argv[1]);
+
+    if (o == NULL) {
+        addReply(c,shared.czero);
+        return;
+    } else {
+        int deleted = 0;
+
+        if (o->type != REDIS_HASH) {
+            addReply(c,shared.wrongtypeerr);
+            return;
+        }
+
+        if (o->encoding == REDIS_ENCODING_ZIPMAP) {
+            o->ptr = zipmapDel((unsigned char*) o->ptr,
+                (unsigned char*) c->argv[2]->ptr,
+                sdslen(c->argv[2]->ptr), &deleted);
+        } else {
+            deleted = dictDelete((dict*)o->ptr,c->argv[2]) == DICT_OK;
+        }
+        addReply(c,deleted ? shared.cone : shared.czero);
+    }
+}
+
+static void convertToRealHash(robj *o) {
+    unsigned char *key, *val, *p, *zm = o->ptr;
+    unsigned int klen, vlen;
+    dict *dict = dictCreate(&hashDictType,NULL);
+
+    assert(o->type == REDIS_HASH && o->encoding != REDIS_ENCODING_HT);
+    p = zipmapRewind(zm);
+    while((p = zipmapNext(p,&key,&klen,&val,&vlen)) != NULL) {
+        robj *keyobj, *valobj;
+
+        keyobj = createStringObject((char*)key,klen);
+        valobj = createStringObject((char*)val,vlen);
+        tryObjectEncoding(keyobj);
+        tryObjectEncoding(valobj);
+        dictAdd(dict,keyobj,valobj);
+    }
+    o->encoding = REDIS_ENCODING_HT;
+    o->ptr = dict;
+    zfree(zm);
+}
+
 /* ========================= Non type-specific commands  ==================== */
 
 static void flushdbCommand(redisClient *c) {
@@ -6050,6 +6472,9 @@ static sds genRedisInfoString(void) {
     time_t uptime = time(NULL)-server.stat_starttime;
     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(),
@@ -6070,6 +6495,8 @@ static sds genRedisInfoString(void) {
         "bgrewriteaof_in_progress:%d\r\n"
         "total_connections_received:%lld\r\n"
         "total_commands_processed:%lld\r\n"
+        "hash_max_zipmap_entries:%ld\r\n"
+        "hash_max_zipmap_value:%ld\r\n"
         "vm_enabled:%d\r\n"
         "role:%s\r\n"
         ,REDIS_VERSION,
@@ -6089,6 +6516,8 @@ static sds genRedisInfoString(void) {
         server.bgrewritechildpid != -1,
         server.stat_numconnections,
         server.stat_numcommands,
+        server.hash_max_zipmap_entries,
+        server.hash_max_zipmap_value,
         server.vm_enabled != 0,
         server.masterhost == NULL ? "master" : "slave"
     );
@@ -6782,9 +7211,9 @@ static void updateSlavesWaitingBgsave(int bgsaveerr) {
 
 static int syncWithMaster(void) {
     char buf[1024], tmpfile[256], authcmd[1024];
-    int dumpsize;
+    long dumpsize;
     int fd = anetTcpConnect(NULL,server.masterhost,server.masterport);
-    int dfd;
+    int dfd, maxtries = 5;
 
     if (fd == -1) {
         redisLog(REDIS_WARNING,"Unable to connect to MASTER: %s",
@@ -6834,11 +7263,16 @@ static int syncWithMaster(void) {
         redisLog(REDIS_WARNING,"Bad protocol from MASTER, the first byte is not '$', are you sure the host and port are right?");
         return REDIS_ERR;
     }
-    dumpsize = atoi(buf+1);
-    redisLog(REDIS_NOTICE,"Receiving %d bytes data dump from MASTER",dumpsize);
+    dumpsize = strtol(buf+1,NULL,10);
+    redisLog(REDIS_NOTICE,"Receiving %ld bytes data dump from MASTER",dumpsize);
     /* Read the bulk write data on a temp file */
-    snprintf(tmpfile,256,"temp-%d.%ld.rdb",(int)time(NULL),(long int)random());
-    dfd = open(tmpfile,O_CREAT|O_WRONLY,0644);
+    while(maxtries--) {
+        snprintf(tmpfile,256,
+            "temp-%d.%ld.rdb",(int)time(NULL),(long int)getpid());
+        dfd = open(tmpfile,O_CREAT|O_WRONLY|O_EXCL,0644);
+        if (dfd != -1) break;
+        sleep(1);
+    }
     if (dfd == -1) {
         close(fd);
         redisLog(REDIS_WARNING,"Opening the temp file needed for MASTER <-> SLAVE synchronization: %s",strerror(errno));
@@ -7178,7 +7612,7 @@ fmterr:
 }
 
 /* Write an object into a file in the bulk format $<count>\r\n<payload>\r\n */
-static int fwriteBulk(FILE *fp, robj *obj) {
+static int fwriteBulkObject(FILE *fp, robj *obj) {
     char buf[128];
     int decrrc = 0;
 
@@ -7203,6 +7637,18 @@ err:
     return 0;
 }
 
+/* Write binary-safe string into a file in the bulkformat
+ * $<count>\r\n<payload>\r\n */
+static int fwriteBulkString(FILE *fp, char *s, unsigned long len) {
+    char buf[128];
+
+    snprintf(buf,sizeof(buf),"$%ld\r\n",(unsigned long)len);
+    if (fwrite(buf,strlen(buf),1,fp) == 0) return 0;
+    if (len && fwrite(s,len,1,fp) == 0) return 0;
+    if (fwrite("\r\n",2,1,fp) == 0) return 0;
+    return 1;
+}
+
 /* Write a double value in bulk format $<count>\r\n<payload>\r\n */
 static int fwriteBulkDouble(FILE *fp, double d) {
     char buf[128], dbuf[128];
@@ -7285,8 +7731,8 @@ static int rewriteAppendOnlyFile(char *filename) {
                 char cmd[]="*3\r\n$3\r\nSET\r\n";
                 if (fwrite(cmd,sizeof(cmd)-1,1,fp) == 0) goto werr;
                 /* Key and value */
-                if (fwriteBulk(fp,key) == 0) goto werr;
-                if (fwriteBulk(fp,o) == 0) goto werr;
+                if (fwriteBulkObject(fp,key) == 0) goto werr;
+                if (fwriteBulkObject(fp,o) == 0) goto werr;
             } else if (o->type == REDIS_LIST) {
                 /* Emit the RPUSHes needed to rebuild the list */
                 list *list = o->ptr;
@@ -7299,8 +7745,8 @@ static int rewriteAppendOnlyFile(char *filename) {
                     robj *eleobj = listNodeValue(ln);
 
                     if (fwrite(cmd,sizeof(cmd)-1,1,fp) == 0) goto werr;
-                    if (fwriteBulk(fp,key) == 0) goto werr;
-                    if (fwriteBulk(fp,eleobj) == 0) goto werr;
+                    if (fwriteBulkObject(fp,key) == 0) goto werr;
+                    if (fwriteBulkObject(fp,eleobj) == 0) goto werr;
                 }
             } else if (o->type == REDIS_SET) {
                 /* Emit the SADDs needed to rebuild the set */
@@ -7313,8 +7759,8 @@ static int rewriteAppendOnlyFile(char *filename) {
                     robj *eleobj = dictGetEntryKey(de);
 
                     if (fwrite(cmd,sizeof(cmd)-1,1,fp) == 0) goto werr;
-                    if (fwriteBulk(fp,key) == 0) goto werr;
-                    if (fwriteBulk(fp,eleobj) == 0) goto werr;
+                    if (fwriteBulkObject(fp,key) == 0) goto werr;
+                    if (fwriteBulkObject(fp,eleobj) == 0) goto werr;
                 }
                 dictReleaseIterator(di);
             } else if (o->type == REDIS_ZSET) {
@@ -7329,11 +7775,43 @@ static int rewriteAppendOnlyFile(char *filename) {
                     double *score = dictGetEntryVal(de);
 
                     if (fwrite(cmd,sizeof(cmd)-1,1,fp) == 0) goto werr;
-                    if (fwriteBulk(fp,key) == 0) goto werr;
+                    if (fwriteBulkObject(fp,key) == 0) goto werr;
                     if (fwriteBulkDouble(fp,*score) == 0) goto werr;
-                    if (fwriteBulk(fp,eleobj) == 0) goto werr;
+                    if (fwriteBulkObject(fp,eleobj) == 0) goto werr;
                 }
                 dictReleaseIterator(di);
+            } else if (o->type == REDIS_HASH) {
+                char cmd[]="*4\r\n$4\r\nHSET\r\n";
+
+                /* Emit the HSETs needed to rebuild the hash */
+                if (o->encoding == REDIS_ENCODING_ZIPMAP) {
+                    unsigned char *p = zipmapRewind(o->ptr);
+                    unsigned char *field, *val;
+                    unsigned int flen, vlen;
+
+                    while((p = zipmapNext(p,&field,&flen,&val,&vlen)) != NULL) {
+                        if (fwrite(cmd,sizeof(cmd)-1,1,fp) == 0) goto werr;
+                        if (fwriteBulkObject(fp,key) == 0) goto werr;
+                        if (fwriteBulkString(fp,(char*)field,flen) == -1)
+                            return -1;
+                        if (fwriteBulkString(fp,(char*)val,vlen) == -1)
+                            return -1;
+                    }
+                } else {
+                    dictIterator *di = dictGetIterator(o->ptr);
+                    dictEntry *de;
+
+                    while((de = dictNext(di)) != NULL) {
+                        robj *field = dictGetEntryKey(de);
+                        robj *val = dictGetEntryVal(de);
+
+                        if (fwrite(cmd,sizeof(cmd)-1,1,fp) == 0) goto werr;
+                        if (fwriteBulkObject(fp,key) == 0) goto werr;
+                        if (fwriteBulkObject(fp,field) == -1) return -1;
+                        if (fwriteBulkObject(fp,val) == -1) return -1;
+                    }
+                    dictReleaseIterator(di);
+                }
             } else {
                 redisAssert(0 != 0);
             }
@@ -7343,7 +7821,7 @@ static int rewriteAppendOnlyFile(char *filename) {
                 /* If this key is already expired skip it */
                 if (expiretime < now) continue;
                 if (fwrite(cmd,sizeof(cmd)-1,1,fp) == 0) goto werr;
-                if (fwriteBulk(fp,key) == 0) goto werr;
+                if (fwriteBulkObject(fp,key) == 0) goto werr;
                 if (fwriteBulkLong(fp,expiretime) == 0) goto werr;
             }
             if (swapped) decrRefCount(o);
@@ -8512,11 +8990,20 @@ static void debugCommand(redisClient *c) {
         val = dictGetEntryVal(de);
         if (!server.vm_enabled || (key->storage == REDIS_VM_MEMORY ||
                                    key->storage == REDIS_VM_SWAPPING)) {
+            char *strenc;
+            char buf[128];
+
+            if (val->encoding < (sizeof(strencoding)/sizeof(char*))) {
+                strenc = strencoding[val->encoding];
+            } else {
+                snprintf(buf,64,"unknown encoding %d\n", val->encoding);
+                strenc = buf;
+            }
             addReplySds(c,sdscatprintf(sdsempty(),
                 "+Key at:%p refcount:%d, value at:%p refcount:%d "
-                "encoding:%d serializedlength:%lld\r\n",
+                "encoding:%s serializedlength:%lld\r\n",
                 (void*)key, key->refcount, (void*)val, val->refcount,
-                val->encoding, (long long) rdbSavedObjectLen(val,NULL)));
+                strenc, (long long) rdbSavedObjectLen(val,NULL)));
         } else {
             addReplySds(c,sdscatprintf(sdsempty(),
                 "+Key at:%p refcount:%d, value swapped at: page %llu "