X-Git-Url: https://git.saurik.com/redis.git/blobdiff_plain/6c446631dac7a7fe9e34b18392d4a8498c8c9bc3..7c49733ce3f550a96f60a9213911fdc9265cedc8:/redis.c

diff --git a/redis.c b/redis.c
index 9221dc0d..61bb81cf 100644
--- a/redis.c
+++ b/redis.c
@@ -27,7 +27,7 @@
  * POSSIBILITY OF SUCH DAMAGE.
  */
 
-#define REDIS_VERSION "1.06"
+#define REDIS_VERSION "1.1.91"
 
 #include "fmacros.h"
 #include "config.h"
@@ -198,6 +198,10 @@
 #define APPENDFSYNC_ALWAYS 1
 #define APPENDFSYNC_EVERYSEC 2
 
+/* We can print the stacktrace, so our assert is defined this way: */
+#define redisAssert(_e) ((_e)?(void)0 : (_redisAssert(#_e),exit(1)))
+static void _redisAssert(char *estr);
+
 /*================================= Data types ============================== */
 
 /* A redis object, that is a type able to hold a string / list / set */
@@ -209,6 +213,17 @@ typedef struct redisObject {
     int refcount;
 } robj;
 
+/* Macro used to initalize a Redis object allocated on the stack.
+ * Note that this macro is taken near the structure definition to make sure
+ * we'll update it when the structure is changed, to avoid bugs like
+ * bug #85 introduced exactly in this way. */
+#define initStaticStringObject(_var,_ptr) do { \
+    _var.refcount = 1; \
+    _var.type = REDIS_STRING; \
+    _var.encoding = REDIS_ENCODING_RAW; \
+    _var.ptr = _ptr; \
+} while(0);
+
 typedef struct redisDb {
     dict *dict;
     dict *expires;
@@ -275,8 +290,9 @@ struct redisServer {
     int appendfd;
     int appendseldb;
     char *pidfile;
-    int bgsaveinprogress;
     pid_t bgsavechildpid;
+    pid_t bgrewritechildpid;
+    sds bgrewritebuf; /* buffer taken by parent during oppend only rewrite */
     struct saveparam *saveparams;
     int saveparamslen;
     char *logfile;
@@ -383,7 +399,7 @@ static void feedAppendOnlyFile(struct redisCommand *cmd, int dictid, robj **argv
 static int syncWithMaster(void);
 static robj *tryObjectSharing(robj *o);
 static int tryObjectEncoding(robj *o);
-static robj *getDecodedObject(const robj *o);
+static robj *getDecodedObject(robj *o);
 static int removeExpire(redisDb *db, robj *key);
 static int expireIfNeeded(redisDb *db, robj *key);
 static int deleteIfVolatile(redisDb *db, robj *key);
@@ -395,6 +411,7 @@ static void freeMemoryIfNeeded(void);
 static int processCommand(redisClient *c);
 static void setupSigSegvAction(void);
 static void rdbRemoveTempFile(pid_t childpid);
+static void aofRemoveTempFile(pid_t childpid);
 static size_t stringObjectLen(robj *o);
 static void processInputBuffer(redisClient *c);
 static zskiplist *zslCreate(void);
@@ -421,6 +438,7 @@ static void dbsizeCommand(redisClient *c);
 static void lastsaveCommand(redisClient *c);
 static void saveCommand(redisClient *c);
 static void bgsaveCommand(redisClient *c);
+static void bgrewriteaofCommand(redisClient *c);
 static void shutdownCommand(redisClient *c);
 static void moveCommand(redisClient *c);
 static void renameCommand(redisClient *c);
@@ -498,7 +516,7 @@ static struct redisCommand cmdTable[] = {
     {"lrange",lrangeCommand,4,REDIS_CMD_INLINE},
     {"ltrim",ltrimCommand,4,REDIS_CMD_INLINE},
     {"lrem",lremCommand,4,REDIS_CMD_BULK},
-    {"rpoplpush",rpoplpushcommand,3,REDIS_CMD_BULK},
+    {"rpoplpush",rpoplpushcommand,3,REDIS_CMD_BULK|REDIS_CMD_DENYOOM},
     {"sadd",saddCommand,3,REDIS_CMD_BULK|REDIS_CMD_DENYOOM},
     {"srem",sremCommand,3,REDIS_CMD_BULK},
     {"smove",smoveCommand,4,REDIS_CMD_BULK},
@@ -518,7 +536,7 @@ static struct redisCommand cmdTable[] = {
     {"zrem",zremCommand,3,REDIS_CMD_BULK},
     {"zremrangebyscore",zremrangebyscoreCommand,4,REDIS_CMD_INLINE},
     {"zrange",zrangeCommand,4,REDIS_CMD_INLINE},
-    {"zrangebyscore",zrangebyscoreCommand,4,REDIS_CMD_INLINE},
+    {"zrangebyscore",zrangebyscoreCommand,-4,REDIS_CMD_INLINE},
     {"zrevrange",zrevrangeCommand,4,REDIS_CMD_INLINE},
     {"zcard",zcardCommand,2,REDIS_CMD_INLINE},
     {"zscore",zscoreCommand,3,REDIS_CMD_BULK|REDIS_CMD_DENYOOM},
@@ -541,6 +559,7 @@ static struct redisCommand cmdTable[] = {
     {"echo",echoCommand,2,REDIS_CMD_BULK},
     {"save",saveCommand,1,REDIS_CMD_INLINE},
     {"bgsave",bgsaveCommand,1,REDIS_CMD_INLINE},
+    {"bgrewriteaof",bgrewriteaofCommand,1,REDIS_CMD_INLINE},
     {"shutdown",shutdownCommand,1,REDIS_CMD_INLINE},
     {"lastsave",lastsaveCommand,1,REDIS_CMD_INLINE},
     {"type",typeCommand,2,REDIS_CMD_INLINE},
@@ -752,37 +771,24 @@ static unsigned int dictObjHash(const void *key) {
 static int dictEncObjKeyCompare(void *privdata, const void *key1,
         const void *key2)
 {
-    const robj *o1 = key1, *o2 = key2;
-
-    if (o1->encoding == REDIS_ENCODING_RAW &&
-        o2->encoding == REDIS_ENCODING_RAW)
-        return sdsDictKeyCompare(privdata,o1->ptr,o2->ptr);
-    else {
-        robj *dec1, *dec2;
-        int cmp;
+    robj *o1 = (robj*) key1, *o2 = (robj*) key2;
+    int cmp;
 
-        dec1 = o1->encoding != REDIS_ENCODING_RAW ?
-            getDecodedObject(o1) : (robj*)o1;
-        dec2 = o2->encoding != REDIS_ENCODING_RAW ?
-            getDecodedObject(o2) : (robj*)o2;
-        cmp = sdsDictKeyCompare(privdata,dec1->ptr,dec2->ptr);
-        if (dec1 != o1) decrRefCount(dec1);
-        if (dec2 != o2) decrRefCount(dec2);
-        return cmp;
-    }
+    o1 = getDecodedObject(o1);
+    o2 = getDecodedObject(o2);
+    cmp = sdsDictKeyCompare(privdata,o1->ptr,o2->ptr);
+    decrRefCount(o1);
+    decrRefCount(o2);
+    return cmp;
 }
 
 static unsigned int dictEncObjHash(const void *key) {
-    const robj *o = key;
+    robj *o = (robj*) key;
 
-    if (o->encoding == REDIS_ENCODING_RAW)
-        return dictGenHashFunction(o->ptr, sdslen((sds)o->ptr));
-    else {
-        robj *dec = getDecodedObject(o);
-        unsigned int hash = dictGenHashFunction(dec->ptr, sdslen((sds)dec->ptr));
-        decrRefCount(dec);
-        return hash;
-    }
+    o = getDecodedObject(o);
+    unsigned int hash = dictGenHashFunction(o->ptr, sdslen((sds)o->ptr));
+    decrRefCount(o);
+    return hash;
 }
 
 static dictType setDictType = {
@@ -800,7 +806,7 @@ static dictType zsetDictType = {
     NULL,                      /* val dup */
     dictEncObjKeyCompare,      /* key compare */
     dictRedisObjectDestructor, /* key destructor */
-    dictVanillaFree            /* val destructor */
+    dictVanillaFree            /* val destructor of malloc(sizeof(double)) */
 };
 
 static dictType hashDictType = {
@@ -820,8 +826,7 @@ static dictType hashDictType = {
  * is based on heap allocation for send buffers, so we simply abort.
  * At least the code will be simpler to read... */
 static void oom(const char *msg) {
-    fprintf(stderr, "%s: Out of memory\n",msg);
-    fflush(stderr);
+    redisLog(REDIS_WARNING, "%s: Out of memory\n",msg);
     sleep(1);
     abort();
 }
@@ -869,6 +874,90 @@ static void tryResizeHashTables(void) {
     }
 }
 
+/* A background saving child (BGSAVE) terminated its work. Handle this. */
+void backgroundSaveDoneHandler(int statloc) {
+    int exitcode = WEXITSTATUS(statloc);
+    int bysignal = WIFSIGNALED(statloc);
+
+    if (!bysignal && exitcode == 0) {
+        redisLog(REDIS_NOTICE,
+            "Background saving terminated with success");
+        server.dirty = 0;
+        server.lastsave = time(NULL);
+    } else if (!bysignal && exitcode != 0) {
+        redisLog(REDIS_WARNING, "Background saving error");
+    } else {
+        redisLog(REDIS_WARNING,
+            "Background saving terminated by signal");
+        rdbRemoveTempFile(server.bgsavechildpid);
+    }
+    server.bgsavechildpid = -1;
+    /* Possibly there are slaves waiting for a BGSAVE in order to be served
+     * (the first stage of SYNC is a bulk transfer of dump.rdb) */
+    updateSlavesWaitingBgsave(exitcode == 0 ? REDIS_OK : REDIS_ERR);
+}
+
+/* A background append only file rewriting (BGREWRITEAOF) terminated its work.
+ * Handle this. */
+void backgroundRewriteDoneHandler(int statloc) {
+    int exitcode = WEXITSTATUS(statloc);
+    int bysignal = WIFSIGNALED(statloc);
+
+    if (!bysignal && exitcode == 0) {
+        int fd;
+        char tmpfile[256];
+
+        redisLog(REDIS_NOTICE,
+            "Background append only file rewriting terminated with success");
+        /* Now it's time to flush the differences accumulated by the parent */
+        snprintf(tmpfile,256,"temp-rewriteaof-bg-%d.aof", (int) server.bgrewritechildpid);
+        fd = open(tmpfile,O_WRONLY|O_APPEND);
+        if (fd == -1) {
+            redisLog(REDIS_WARNING, "Not able to open the temp append only file produced by the child: %s", strerror(errno));
+            goto cleanup;
+        }
+        /* Flush our data... */
+        if (write(fd,server.bgrewritebuf,sdslen(server.bgrewritebuf)) !=
+                (signed) sdslen(server.bgrewritebuf)) {
+            redisLog(REDIS_WARNING, "Error or short write trying to flush the parent diff of the append log file in the child temp file: %s", strerror(errno));
+            close(fd);
+            goto cleanup;
+        }
+        redisLog(REDIS_NOTICE,"Parent diff flushed into the new append log file with success (%lu bytes)",sdslen(server.bgrewritebuf));
+        /* Now our work is to rename the temp file into the stable file. And
+         * switch the file descriptor used by the server for append only. */
+        if (rename(tmpfile,server.appendfilename) == -1) {
+            redisLog(REDIS_WARNING,"Can't rename the temp append only file into the stable one: %s", strerror(errno));
+            close(fd);
+            goto cleanup;
+        }
+        /* Mission completed... almost */
+        redisLog(REDIS_NOTICE,"Append only file successfully rewritten.");
+        if (server.appendfd != -1) {
+            /* If append only is actually enabled... */
+            close(server.appendfd);
+            server.appendfd = fd;
+            fsync(fd);
+            server.appendseldb = -1; /* Make sure it will issue SELECT */
+            redisLog(REDIS_NOTICE,"The new append only file was selected for future appends.");
+        } else {
+            /* If append only is disabled we just generate a dump in this
+             * format. Why not? */
+            close(fd);
+        }
+    } else if (!bysignal && exitcode != 0) {
+        redisLog(REDIS_WARNING, "Background append only file rewriting error");
+    } else {
+        redisLog(REDIS_WARNING,
+            "Background append only file rewriting terminated by signal");
+    }
+cleanup:
+    sdsfree(server.bgrewritebuf);
+    server.bgrewritebuf = sdsempty();
+    aofRemoveTempFile(server.bgrewritechildpid);
+    server.bgrewritechildpid = -1;
+}
+
 static int serverCron(struct aeEventLoop *eventLoop, long long id, void *clientData) {
     int j, loops = server.cronloops++;
     REDIS_NOTUSED(eventLoop);
@@ -897,7 +986,7 @@ 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.bgsaveinprogress) tryResizeHashTables();
+    if (server.bgsavechildpid == -1) tryResizeHashTables();
 
     /* Show information about connected clients */
     if (!(loops % 5)) {
@@ -912,28 +1001,17 @@ static int serverCron(struct aeEventLoop *eventLoop, long long id, void *clientD
     if (server.maxidletime && !(loops % 10))
         closeTimedoutClients();
 
-    /* Check if a background saving in progress terminated */
-    if (server.bgsaveinprogress) {
+    /* Check if a background saving or AOF rewrite in progress terminated */
+    if (server.bgsavechildpid != -1 || server.bgrewritechildpid != -1) {
         int statloc;
-        if (wait3(&statloc,WNOHANG,NULL)) {
-            int exitcode = WEXITSTATUS(statloc);
-            int bysignal = WIFSIGNALED(statloc);
-
-            if (!bysignal && exitcode == 0) {
-                redisLog(REDIS_NOTICE,
-                    "Background saving terminated with success");
-                server.dirty = 0;
-                server.lastsave = time(NULL);
-            } else if (!bysignal && exitcode != 0) {
-                redisLog(REDIS_WARNING, "Background saving error");
+        pid_t pid;
+
+        if ((pid = wait3(&statloc,WNOHANG,NULL)) != 0) {
+            if (pid == server.bgsavechildpid) {
+                backgroundSaveDoneHandler(statloc);
             } else {
-                redisLog(REDIS_WARNING,
-                    "Background saving terminated by signal");
-                rdbRemoveTempFile(server.bgsavechildpid);
+                backgroundRewriteDoneHandler(statloc);
             }
-            server.bgsaveinprogress = 0;
-            server.bgsavechildpid = -1;
-            updateSlavesWaitingBgsave(exitcode == 0 ? REDIS_OK : REDIS_ERR);
         }
     } else {
         /* If there is not a background saving in progress check if
@@ -1060,7 +1138,7 @@ static void initServerConfig() {
     server.appendseldb = -1; /* Make sure the first time will not match */
     server.pidfile = "/var/run/redis.pid";
     server.dbfilename = "dump.rdb";
-    server.appendfilename = "appendonly.log";
+    server.appendfilename = "appendonly.aof";
     server.requirepass = NULL;
     server.shareobjects = 0;
     server.sharingpoolsize = 1024;
@@ -1112,8 +1190,9 @@ static void initServer() {
         server.db[j].id = j;
     }
     server.cronloops = 0;
-    server.bgsaveinprogress = 0;
     server.bgsavechildpid = -1;
+    server.bgrewritechildpid = -1;
+    server.bgrewritebuf = sdsempty();
     server.lastsave = time(NULL);
     server.dirty = 0;
     server.usedmemory = 0;
@@ -1332,14 +1411,14 @@ static void freeClient(redisClient *c) {
     freeClientArgv(c);
     close(c->fd);
     ln = listSearchKey(server.clients,c);
-    assert(ln != NULL);
+    redisAssert(ln != NULL);
     listDelNode(server.clients,ln);
     if (c->flags & REDIS_SLAVE) {
         if (c->replstate == REDIS_REPL_SEND_BULK && c->repldbfd != -1)
             close(c->repldbfd);
         list *l = (c->flags & REDIS_MONITOR) ? server.monitors : server.slaves;
         ln = listSearchKey(l,c);
-        assert(ln != NULL);
+        redisAssert(ln != NULL);
         listDelNode(l,ln);
     }
     if (c->flags & REDIS_MASTER) {
@@ -1634,7 +1713,10 @@ static int processCommand(redisClient *c) {
         return 1;
     } else if ((cmd->arity > 0 && cmd->arity != c->argc) ||
                (c->argc < -cmd->arity)) {
-        addReplySds(c,sdsnew("-ERR wrong number of arguments\r\n"));
+        addReplySds(c,
+            sdscatprintf(sdsempty(),
+                "-ERR wrong number of arguments for '%s' command\r\n",
+                cmd->name));
         resetClient(c);
         return 1;
     } else if (server.maxmemory && cmd->flags & REDIS_CMD_DENYOOM && zmalloc_used_memory() > server.maxmemory) {
@@ -1722,8 +1804,8 @@ static void replicationFeedSlaves(list *slaves, struct redisCommand *cmd, int di
             robj *lenobj;
 
             lenobj = createObject(REDIS_STRING,
-                sdscatprintf(sdsempty(),"%d\r\n",
-                    stringObjectLen(argv[j])));
+                sdscatprintf(sdsempty(),"%lu\r\n",
+                    (unsigned long) stringObjectLen(argv[j])));
             lenobj->refcount = 0;
             outv[outc++] = lenobj;
         }
@@ -1798,6 +1880,7 @@ again:
             if (sdslen(query) == 0) {
                 /* Ignore empty query */
                 sdsfree(query);
+                if (sdslen(c->querybuf)) goto again;
                 return;
             }
             argv = sdssplitlen(query,sdslen(query)," ",1,&argc);
@@ -1815,10 +1898,16 @@ again:
                 }
             }
             zfree(argv);
-            /* Execute the command. If the client is still valid
-             * after processCommand() return and there is something
-             * on the query buffer try to process the next command. */
-            if (c->argc && processCommand(c) && sdslen(c->querybuf)) goto again;
+            if (c->argc) {
+                /* Execute the command. If the client is still valid
+                 * after processCommand() return and there is something
+                 * on the query buffer try to process the next command. */
+                if (processCommand(c) && sdslen(c->querybuf)) goto again;
+            } else {
+                /* Nothing to process, argc == 0. Just process the query
+                 * buffer if it's not empty or return to the caller */
+                if (sdslen(c->querybuf)) goto again;
+            }
             return;
         } else if (sdslen(c->querybuf) >= REDIS_REQUEST_MAX_SIZE) {
             redisLog(REDIS_DEBUG, "Client protocol error");
@@ -1926,12 +2015,7 @@ static void addReply(redisClient *c, robj *obj) {
          c->replstate == REDIS_REPL_ONLINE) &&
         aeCreateFileEvent(server.el, c->fd, AE_WRITABLE,
         sendReplyToClient, c) == AE_ERR) return;
-    if (obj->encoding != REDIS_ENCODING_RAW) {
-        obj = getDecodedObject(obj);
-    } else {
-        incrRefCount(obj);
-    }
-    listAddNodeTail(c->reply,obj);
+    listAddNodeTail(c->reply,getDecodedObject(obj));
 }
 
 static void addReplySds(redisClient *c, sds s) {
@@ -1944,8 +2028,8 @@ static void addReplyDouble(redisClient *c, double d) {
     char buf[128];
 
     snprintf(buf,sizeof(buf),"%.17g",d);
-    addReplySds(c,sdscatprintf(sdsempty(),"$%d\r\n%s\r\n",
-        strlen(buf),buf));
+    addReplySds(c,sdscatprintf(sdsempty(),"$%lu\r\n%s\r\n",
+        (unsigned long) strlen(buf),buf));
 }
 
 static void addReplyBulkLen(redisClient *c, robj *obj) {
@@ -1965,7 +2049,7 @@ static void addReplyBulkLen(redisClient *c, robj *obj) {
             len++;
         }
     }
-    addReplySds(c,sdscatprintf(sdsempty(),"$%d\r\n",len));
+    addReplySds(c,sdscatprintf(sdsempty(),"$%lu\r\n",(unsigned long)len));
 }
 
 static void acceptHandler(aeEventLoop *el, int fd, void *privdata, int mask) {
@@ -2095,7 +2179,7 @@ static void decrRefCount(void *obj) {
         case REDIS_SET: freeSetObject(o); break;
         case REDIS_ZSET: freeZsetObject(o); break;
         case REDIS_HASH: freeHashObject(o); break;
-        default: assert(0 != 0); break;
+        default: redisAssert(0 != 0); break;
         }
         if (listLength(server.objfreelist) > REDIS_OBJFREELIST_MAX ||
             !listAddNodeHead(server.objfreelist,o))
@@ -2140,7 +2224,7 @@ static robj *tryObjectSharing(robj *o) {
 
     if (o == NULL || server.shareobjects == 0) return o;
 
-    assert(o->type == REDIS_STRING);
+    redisAssert(o->type == REDIS_STRING);
     de = dictFind(server.sharingpool,o);
     if (de) {
         robj *shared = dictGetEntryKey(de);
@@ -2158,7 +2242,7 @@ static robj *tryObjectSharing(robj *o) {
         if (dictSize(server.sharingpool) >=
                 server.sharingpoolsize) {
             de = dictGetRandomKey(server.sharingpool);
-            assert(de != NULL);
+            redisAssert(de != NULL);
             c = ((unsigned long) dictGetEntryVal(de))-1;
             dictGetEntryVal(de) = (void*) c;
             if (c == 0) {
@@ -2171,7 +2255,7 @@ static robj *tryObjectSharing(robj *o) {
             int retval;
 
             retval = dictAdd(server.sharingpool,o,(void*)1);
-            assert(retval == DICT_OK);
+            redisAssert(retval == DICT_OK);
             incrRefCount(o);
         }
         return o;
@@ -2214,7 +2298,7 @@ static int tryObjectEncoding(robj *o) {
      if (o->refcount > 1) return REDIS_ERR;
 
     /* Currently we try to encode only strings */
-    assert(o->type == REDIS_STRING);
+    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;
@@ -2226,11 +2310,15 @@ static int tryObjectEncoding(robj *o) {
     return REDIS_OK;
 }
 
-/* Get a decoded version of an encoded object (returned as a new object) */
-static robj *getDecodedObject(const robj *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;
     
-    assert(o->encoding != REDIS_ENCODING_RAW);
+    if (o->encoding == REDIS_ENCODING_RAW) {
+        incrRefCount(o);
+        return o;
+    }
     if (o->type == REDIS_STRING && o->encoding == REDIS_ENCODING_INT) {
         char buf[32];
 
@@ -2238,16 +2326,20 @@ static robj *getDecodedObject(const robj *o) {
         dec = createStringObject(buf,strlen(buf));
         return dec;
     } else {
-        assert(1 != 1);
+        redisAssert(1 != 1);
     }
 }
 
 /* Compare two string objects via strcmp() or alike.
  * Note that the objects may be integer-encoded. In such a case we
  * use snprintf() to get a string representation of the numbers on the stack
- * and compare the strings, it's much faster than calling getDecodedObject(). */
+ * and compare the strings, it's much faster than calling getDecodedObject().
+ *
+ * Important note: if objects are not integer encoded, but binary-safe strings,
+ * sdscmp() from sds.c will apply memcmp() so this function ca be considered
+ * binary safe. */
 static int compareStringObjects(robj *a, robj *b) {
-    assert(a->type == REDIS_STRING && b->type == REDIS_STRING);
+    redisAssert(a->type == REDIS_STRING && b->type == REDIS_STRING);
     char bufa[128], bufb[128], *astr, *bstr;
     int bothsds = 1;
 
@@ -2270,7 +2362,7 @@ static int compareStringObjects(robj *a, robj *b) {
 }
 
 static size_t stringObjectLen(robj *o) {
-    assert(o->type == REDIS_STRING);
+    redisAssert(o->type == REDIS_STRING);
     if (o->encoding == REDIS_ENCODING_RAW) {
         return sdslen(o->ptr);
     } else {
@@ -2419,16 +2511,11 @@ static int rdbSaveStringObjectRaw(FILE *fp, robj *obj) {
 /* Like rdbSaveStringObjectRaw() but handle encoded objects */
 static int rdbSaveStringObject(FILE *fp, robj *obj) {
     int retval;
-    robj *dec;
 
-    if (obj->encoding != REDIS_ENCODING_RAW) {
-        dec = getDecodedObject(obj);
-        retval = rdbSaveStringObjectRaw(fp,dec);
-        decrRefCount(dec);
-        return retval;
-    } else {
-        return rdbSaveStringObjectRaw(fp,obj);
-    }
+    obj = getDecodedObject(obj);
+    retval = rdbSaveStringObjectRaw(fp,obj);
+    decrRefCount(obj);
+    return retval;
 }
 
 /* Save a double value. Doubles are saved as strings prefixed by an unsigned
@@ -2548,7 +2635,7 @@ static int rdbSave(char *filename) {
                 }
                 dictReleaseIterator(di);
             } else {
-                assert(0 != 0);
+                redisAssert(0 != 0);
             }
         }
         dictReleaseIterator(di);
@@ -2584,7 +2671,7 @@ werr:
 static int rdbSaveBackground(char *filename) {
     pid_t childpid;
 
-    if (server.bgsaveinprogress) return REDIS_ERR;
+    if (server.bgsavechildpid != -1) return REDIS_ERR;
     if ((childpid = fork()) == 0) {
         /* Child */
         close(server.fd);
@@ -2601,7 +2688,6 @@ static int rdbSaveBackground(char *filename) {
             return REDIS_ERR;
         }
         redisLog(REDIS_NOTICE,"Background saving started by pid %d",childpid);
-        server.bgsaveinprogress = 1;
         server.bgsavechildpid = childpid;
         return REDIS_OK;
     }
@@ -2683,7 +2769,7 @@ static robj *rdbLoadIntegerObject(FILE *fp, int enctype) {
         val = (int32_t)v;
     } else {
         val = 0; /* anti-warning */
-        assert(0!=0);
+        redisAssert(0!=0);
     }
     return createObject(REDIS_STRING,sdscatprintf(sdsempty(),"%lld",val));
 }
@@ -2722,7 +2808,7 @@ static robj *rdbLoadStringObject(FILE*fp, int rdbver) {
         case REDIS_RDB_ENC_LZF:
             return tryObjectSharing(rdbLoadLzfStringObject(fp,rdbver));
         default:
-            assert(0!=0);
+            redisAssert(0!=0);
         }
     }
 
@@ -2747,6 +2833,7 @@ static int rdbLoadDoubleValue(FILE *fp, double *val) {
     case 253: *val = R_Nan; return 0;
     default:
         if (fread(buf,len,1,fp) == 0) return -1;
+        buf[len] = '\0';
         sscanf(buf, "%lg", val);
         return 0;
     }
@@ -2848,7 +2935,7 @@ static int rdbLoad(char *filename) {
                 incrRefCount(ele); /* added to skiplist */
             }
         } else {
-            assert(0 != 0);
+            redisAssert(0 != 0);
         }
         /* Add the new object in the hash table */
         retval = dictAdd(d,keyobj,o);
@@ -2902,6 +2989,7 @@ static void echoCommand(redisClient *c) {
 static void setGenericCommand(redisClient *c, int nx) {
     int retval;
 
+    if (nx) deleteIfVolatile(c->db,c->argv[1]);
     retval = dictAdd(c->db->dict,c->argv[1],c->argv[2]);
     if (retval == DICT_ERR) {
         if (!nx) {
@@ -2977,26 +3065,30 @@ static void mgetCommand(redisClient *c) {
 }
 
 static void msetGenericCommand(redisClient *c, int nx) {
-    int j;
+    int j, busykeys = 0;
 
     if ((c->argc % 2) == 0) {
-        addReplySds(c,sdsnew("-ERR wrong number of arguments\r\n"));
+        addReplySds(c,sdsnew("-ERR wrong number of arguments for MSET\r\n"));
         return;
     }
     /* Handle the NX flag. The MSETNX semantic is to return zero and don't
      * set nothing at all if at least one already key exists. */
     if (nx) {
         for (j = 1; j < c->argc; j += 2) {
-            if (dictFind(c->db->dict,c->argv[j]) != NULL) {
-                addReply(c, shared.czero);
-                return;
+            if (lookupKeyWrite(c->db,c->argv[j]) != NULL) {
+                busykeys++;
             }
         }
     }
+    if (busykeys) {
+        addReply(c, shared.czero);
+        return;
+    }
 
     for (j = 1; j < c->argc; j += 2) {
         int retval;
 
+        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]);
@@ -3038,7 +3130,7 @@ static void incrDecrCommand(redisClient *c, long long incr) {
             else if (o->encoding == REDIS_ENCODING_INT)
                 value = (long)o->ptr;
             else
-                assert(1 != 1);
+                redisAssert(1 != 1);
         }
     }
 
@@ -3136,7 +3228,7 @@ static void keysCommand(redisClient *c) {
     dictEntry *de;
     sds pattern = c->argv[1]->ptr;
     int plen = sdslen(pattern);
-    int numkeys = 0, keyslen = 0;
+    unsigned long numkeys = 0, keyslen = 0;
     robj *lenobj = createObject(REDIS_STRING,NULL);
 
     di = dictGetIterator(c->db->dict);
@@ -3193,7 +3285,7 @@ static void typeCommand(redisClient *c) {
 }
 
 static void saveCommand(redisClient *c) {
-    if (server.bgsaveinprogress) {
+    if (server.bgsavechildpid != -1) {
         addReplySds(c,sdsnew("-ERR background save in progress\r\n"));
         return;
     }
@@ -3205,12 +3297,13 @@ static void saveCommand(redisClient *c) {
 }
 
 static void bgsaveCommand(redisClient *c) {
-    if (server.bgsaveinprogress) {
+    if (server.bgsavechildpid != -1) {
         addReplySds(c,sdsnew("-ERR background save already in progress\r\n"));
         return;
     }
     if (rdbSaveBackground(server.dbfilename) == REDIS_OK) {
-        addReply(c,shared.ok);
+        char *status = "+Background saving started\r\n";
+        addReplySds(c,sdsnew(status));
     } else {
         addReply(c,shared.err);
     }
@@ -3221,7 +3314,7 @@ static void shutdownCommand(redisClient *c) {
     /* Kill the saving child if there is a background saving in progress.
        We want to avoid race conditions, for instance our saving child may
        overwrite the synchronous saving did by SHUTDOWN. */
-    if (server.bgsaveinprogress) {
+    if (server.bgsavechildpid != -1) {
         redisLog(REDIS_WARNING,"There is a live saving child. Killing it!");
         kill(server.bgsavechildpid,SIGKILL);
         rdbRemoveTempFile(server.bgsavechildpid);
@@ -3793,7 +3886,7 @@ static void scardCommand(redisClient *c) {
             addReply(c,shared.wrongtypeerr);
         } else {
             s = o->ptr;
-            addReplySds(c,sdscatprintf(sdsempty(),":%d\r\n",
+            addReplySds(c,sdscatprintf(sdsempty(),":%lu\r\n",
                 dictSize(s)));
         }
     }
@@ -3858,12 +3951,12 @@ static int qsortCompareSetsByCardinality(const void *s1, const void *s2) {
     return dictSize(*d1)-dictSize(*d2);
 }
 
-static void sinterGenericCommand(redisClient *c, robj **setskeys, int setsnum, robj *dstkey) {
+static void sinterGenericCommand(redisClient *c, robj **setskeys, unsigned long setsnum, robj *dstkey) {
     dict **dv = zmalloc(sizeof(dict*)*setsnum);
     dictIterator *di;
     dictEntry *de;
     robj *lenobj = NULL, *dstset = NULL;
-    int j, cardinality = 0;
+    unsigned long j, cardinality = 0;
 
     for (j = 0; j < setsnum; j++) {
         robj *setobj;
@@ -3875,7 +3968,7 @@ static void sinterGenericCommand(redisClient *c, robj **setskeys, int setsnum, r
             zfree(dv);
             if (dstkey) {
                 deleteKey(c->db,dstkey);
-                addReply(c,shared.ok);
+                addReply(c,shared.czero);
             } else {
                 addReply(c,shared.nullmultibulk);
             }
@@ -3940,9 +4033,9 @@ static void sinterGenericCommand(redisClient *c, robj **setskeys, int setsnum, r
     }
 
     if (!dstkey) {
-        lenobj->ptr = sdscatprintf(sdsempty(),"*%d\r\n",cardinality);
+        lenobj->ptr = sdscatprintf(sdsempty(),"*%lu\r\n",cardinality);
     } else {
-        addReplySds(c,sdscatprintf(sdsempty(),":%d\r\n",
+        addReplySds(c,sdscatprintf(sdsempty(),":%lu\r\n",
             dictSize((dict*)dstset->ptr)));
         server.dirty++;
     }
@@ -4044,7 +4137,7 @@ static void sunionDiffGenericCommand(redisClient *c, robj **setskeys, int setsnu
     if (!dstkey) {
         decrRefCount(dstset);
     } else {
-        addReplySds(c,sdscatprintf(sdsempty(),":%d\r\n",
+        addReplySds(c,sdscatprintf(sdsempty(),":%lu\r\n",
             dictSize((dict*)dstset->ptr)));
         server.dirty++;
     }
@@ -4330,14 +4423,14 @@ static void zaddGenericCommand(redisClient *c, robj *key, robj *ele, double scor
         
         /* case 2: Score update operation */
         de = dictFind(zs->dict,ele);
-        assert(de != NULL);
+        redisAssert(de != NULL);
         oldscore = dictGetEntryVal(de);
         if (*score != *oldscore) {
             int deleted;
 
             /* Remove and insert the element in the skip list with new score */
             deleted = zslDelete(zs->zsl,*oldscore,ele);
-            assert(deleted != 0);
+            redisAssert(deleted != 0);
             zslInsert(zs->zsl,*score,ele);
             incrRefCount(ele);
             /* Update the score in the hash table */
@@ -4392,7 +4485,7 @@ static void zremCommand(redisClient *c) {
         /* Delete from the skiplist */
         oldscore = dictGetEntryVal(de);
         deleted = zslDelete(zs->zsl,*oldscore,c->argv[2]);
-        assert(deleted != 0);
+        redisAssert(deleted != 0);
 
         /* Delete from the hash table */
         dictDelete(zs->dict,c->argv[2]);
@@ -4496,6 +4589,20 @@ static void zrangebyscoreCommand(redisClient *c) {
     robj *o;
     double min = strtod(c->argv[2]->ptr,NULL);
     double max = strtod(c->argv[3]->ptr,NULL);
+    int offset = 0, limit = -1;
+
+    if (c->argc != 4 && c->argc != 7) {
+        addReplySds(c,
+            sdsnew("-ERR wrong number of arguments for ZRANGEBYSCORE\r\n"));
+        return;
+    } else if (c->argc == 7 && strcasecmp(c->argv[4]->ptr,"limit")) {
+        addReply(c,shared.syntaxerr);
+        return;
+    } else if (c->argc == 7) {
+        offset = atoi(c->argv[5]->ptr);
+        limit = atoi(c->argv[6]->ptr);
+        if (offset < 0) offset = 0;
+    }
 
     o = lookupKeyRead(c->db,c->argv[1]);
     if (o == NULL) {
@@ -4524,14 +4631,22 @@ static void zrangebyscoreCommand(redisClient *c) {
              * it later */
             lenobj = createObject(REDIS_STRING,NULL);
             addReply(c,lenobj);
+            decrRefCount(lenobj);
 
             while(ln && ln->score <= max) {
+                if (offset) {
+                    offset--;
+                    ln = ln->forward[0];
+                    continue;
+                }
+                if (limit == 0) break;
                 ele = ln->obj;
                 addReplyBulkLen(c,ele);
                 addReply(c,ele);
                 addReply(c,shared.crlf);
                 ln = ln->forward[0];
                 rangelen++;
+                if (limit > 0) limit--;
             }
             lenobj->ptr = sdscatprintf(sdsempty(),"*%d\r\n",rangelen);
         }
@@ -4551,7 +4666,7 @@ static void zcardCommand(redisClient *c) {
             addReply(c,shared.wrongtypeerr);
         } else {
             zs = o->ptr;
-            addReplySds(c,sdscatprintf(sdsempty(),":%d\r\n",zs->zsl->length));
+            addReplySds(c,sdscatprintf(sdsempty(),":%lu\r\n",zs->zsl->length));
         }
     }
 }
@@ -4628,15 +4743,9 @@ static robj *lookupKeyByPattern(redisDb *db, robj *pattern, robj *subst) {
     }
 
     /* The substitution object may be specially encoded. If so we create
-     * a decoded object on the fly. */
-    if (subst->encoding == REDIS_ENCODING_RAW)
-        /* If we don't need to get a decoded object increment the refcount
-         * so that the final decrRefCount() call will restore the original
-         * count */
-        incrRefCount(subst);
-    else {
-        subst = getDecodedObject(subst);
-    }
+     * a decoded object on the fly. Otherwise getDecodedObject will just
+     * increment the ref count, that we'll decrement later. */
+    subst = getDecodedObject(subst);
 
     ssub = subst->ptr;
     if (sdslen(spat)+sdslen(ssub)-1 > REDIS_SORTKEY_MAX) return NULL;
@@ -4655,10 +4764,7 @@ static robj *lookupKeyByPattern(redisDb *db, robj *pattern, robj *subst) {
     keyname.buf[prefixlen+sublen+postfixlen] = '\0';
     keyname.len = prefixlen+sublen+postfixlen;
 
-    keyobj.refcount = 1;
-    keyobj.type = REDIS_STRING;
-    keyobj.ptr = ((char*)&keyname)+(sizeof(long)*2);
-
+    initStaticStringObject(keyobj,((char*)&keyname)+(sizeof(long)*2))
     decrRefCount(subst);
 
     /* printf("lookup '%s' => %p\n", keyname.buf,de); */
@@ -4698,20 +4804,13 @@ static int sortCompare(const void *s1, const void *s2) {
             }
         } else {
             /* Compare elements directly */
-            if (so1->obj->encoding == REDIS_ENCODING_RAW &&
-                so2->obj->encoding == REDIS_ENCODING_RAW) {
-                cmp = strcoll(so1->obj->ptr,so2->obj->ptr);
-            } else {
-                robj *dec1, *dec2;
-
-                dec1 = so1->obj->encoding == REDIS_ENCODING_RAW ?
-                    so1->obj : getDecodedObject(so1->obj);
-                dec2 = so2->obj->encoding == REDIS_ENCODING_RAW ?
-                    so2->obj : getDecodedObject(so2->obj);
-                cmp = strcoll(dec1->ptr,dec2->ptr);
-                if (dec1 != so1->obj) decrRefCount(dec1);
-                if (dec2 != so2->obj) decrRefCount(dec2);
-            }
+            robj *dec1, *dec2;
+
+            dec1 = getDecodedObject(so1->obj);
+            dec2 = getDecodedObject(so2->obj);
+            cmp = strcoll(dec1->ptr,dec2->ptr);
+            decrRefCount(dec1);
+            decrRefCount(dec2);
         }
     }
     return server.sort_desc ? -cmp : cmp;
@@ -4735,7 +4834,9 @@ static void sortCommand(redisClient *c) {
         addReply(c,shared.nokeyerr);
         return;
     }
-    if (sortval->type != REDIS_SET && sortval->type != REDIS_LIST) {
+    if (sortval->type != REDIS_SET && sortval->type != REDIS_LIST &&
+        sortval->type != REDIS_ZSET)
+    {
         addReply(c,shared.wrongtypeerr);
         return;
     }
@@ -4788,11 +4889,15 @@ static void sortCommand(redisClient *c) {
     }
 
     /* Load the sorting vector with all the objects to sort */
-    vectorlen = (sortval->type == REDIS_LIST) ?
-        listLength((list*)sortval->ptr) :
-        dictSize((dict*)sortval->ptr);
+    switch(sortval->type) {
+    case REDIS_LIST: vectorlen = listLength((list*)sortval->ptr); break;
+    case REDIS_SET: vectorlen =  dictSize((dict*)sortval->ptr); break;
+    case REDIS_ZSET: vectorlen = dictSize(((zset*)sortval->ptr)->dict); break;
+    default: vectorlen = 0; redisAssert(0); /* Avoid GCC warning */
+    }
     vector = zmalloc(sizeof(redisSortObject)*vectorlen);
     j = 0;
+
     if (sortval->type == REDIS_LIST) {
         list *list = sortval->ptr;
         listNode *ln;
@@ -4806,10 +4911,17 @@ static void sortCommand(redisClient *c) {
             j++;
         }
     } else {
-        dict *set = sortval->ptr;
+        dict *set;
         dictIterator *di;
         dictEntry *setele;
 
+        if (sortval->type == REDIS_SET) {
+            set = sortval->ptr;
+        } else {
+            zset *zs = sortval->ptr;
+            set = zs->dict;
+        }
+
         di = dictGetIterator(set);
         while((setele = dictNext(di)) != NULL) {
             vector[j].obj = dictGetEntryKey(setele);
@@ -4819,7 +4931,7 @@ static void sortCommand(redisClient *c) {
         }
         dictReleaseIterator(di);
     }
-    assert(j == vectorlen);
+    redisAssert(j == vectorlen);
 
     /* Now it's time to load the right scores in the sorting vector */
     if (dontsort == 0) {
@@ -4830,20 +4942,18 @@ static void sortCommand(redisClient *c) {
                 byval = lookupKeyByPattern(c->db,sortby,vector[j].obj);
                 if (!byval || byval->type != REDIS_STRING) continue;
                 if (alpha) {
-                    if (byval->encoding == REDIS_ENCODING_RAW) {
-                        vector[j].u.cmpobj = byval;
-                        incrRefCount(byval);
-                    } else {
-                        vector[j].u.cmpobj = getDecodedObject(byval);
-                    }
+                    vector[j].u.cmpobj = getDecodedObject(byval);
                 } else {
                     if (byval->encoding == REDIS_ENCODING_RAW) {
                         vector[j].u.score = strtod(byval->ptr,NULL);
                     } else {
+                        /* Don't need to decode the object if it's
+                         * integer-encoded (the only encoding supported) so
+                         * far. We can just cast it */
                         if (byval->encoding == REDIS_ENCODING_INT) {
                             vector[j].u.score = (long)byval->ptr;
                         } else
-                            assert(1 != 1);
+                            redisAssert(1 != 1);
                     }
                 }
             } else {
@@ -4854,7 +4964,7 @@ static void sortCommand(redisClient *c) {
                         if (vector[j].obj->encoding == REDIS_ENCODING_INT)
                             vector[j].u.score = (long) vector[j].obj->ptr;
                         else
-                            assert(1 != 1);
+                            redisAssert(1 != 1);
                     }
                 }
             }
@@ -4909,7 +5019,7 @@ static void sortCommand(redisClient *c) {
                         addReply(c,shared.crlf);
                     }
                 } else {
-                    assert(sop->type == REDIS_SORT_GET); /* always fails */
+                    redisAssert(sop->type == REDIS_SORT_GET); /* always fails */
                 }
             }
         }
@@ -4938,7 +5048,7 @@ static void sortCommand(redisClient *c) {
                         incrRefCount(val);
                     }
                 } else {
-                    assert(sop->type == REDIS_SORT_GET); /* always fails */
+                    redisAssert(sop->type == REDIS_SORT_GET); /* always fails */
                 }
             }
         }
@@ -4962,7 +5072,10 @@ static void sortCommand(redisClient *c) {
     zfree(vector);
 }
 
-static void infoCommand(redisClient *c) {
+/* Create the string returned by the INFO command. This is decoupled
+ * by the INFO command itself as we need to report the same information
+ * on memory corruption problems. */
+static sds genRedisInfoString(void) {
     sds info;
     time_t uptime = time(NULL)-server.stat_starttime;
     int j;
@@ -4970,27 +5083,31 @@ static void infoCommand(redisClient *c) {
     info = sdscatprintf(sdsempty(),
         "redis_version:%s\r\n"
         "arch_bits:%s\r\n"
-        "uptime_in_seconds:%d\r\n"
-        "uptime_in_days:%d\r\n"
+        "multiplexing_api:%s\r\n"
+        "uptime_in_seconds:%ld\r\n"
+        "uptime_in_days:%ld\r\n"
         "connected_clients:%d\r\n"
         "connected_slaves:%d\r\n"
         "used_memory:%zu\r\n"
         "changes_since_last_save:%lld\r\n"
         "bgsave_in_progress:%d\r\n"
-        "last_save_time:%d\r\n"
+        "last_save_time:%ld\r\n"
+        "bgrewriteaof_in_progress:%d\r\n"
         "total_connections_received:%lld\r\n"
         "total_commands_processed:%lld\r\n"
         "role:%s\r\n"
         ,REDIS_VERSION,
         (sizeof(long) == 8) ? "64" : "32",
+        aeGetApiName(),
         uptime,
         uptime/(3600*24),
         listLength(server.clients)-listLength(server.slaves),
         listLength(server.slaves),
         server.usedmemory,
         server.dirty,
-        server.bgsaveinprogress,
+        server.bgsavechildpid != -1,
         server.lastsave,
+        server.bgrewritechildpid != -1,
         server.stat_numconnections,
         server.stat_numcommands,
         server.masterhost == NULL ? "master" : "slave"
@@ -5014,11 +5131,17 @@ static void infoCommand(redisClient *c) {
         keys = dictSize(server.db[j].dict);
         vkeys = dictSize(server.db[j].expires);
         if (keys || vkeys) {
-            info = sdscatprintf(info, "db%d: keys=%lld,expires=%lld\r\n",
+            info = sdscatprintf(info, "db%d:keys=%lld,expires=%lld\r\n",
                 j, keys, vkeys);
         }
     }
-    addReplySds(c,sdscatprintf(sdsempty(),"$%d\r\n",sdslen(info)));
+    return info;
+}
+
+static void infoCommand(redisClient *c) {
+    sds info = genRedisInfoString();
+    addReplySds(c,sdscatprintf(sdsempty(),"$%lu\r\n",
+        (unsigned long)sdslen(info)));
     addReplySds(c,info);
     addReply(c,shared.crlf);
 }
@@ -5217,7 +5340,7 @@ static void syncCommand(redisClient *c) {
     redisLog(REDIS_NOTICE,"Slave ask for synchronization");
     /* Here we need to check if there is a background saving operation
      * in progress, or if it is required to start one */
-    if (server.bgsaveinprogress) {
+    if (server.bgsavechildpid != -1) {
         /* Ok a background save is in progress. Let's check if it is a good
          * one for replication, i.e. if there is another slave that is
          * registering differences since the server forked to save */
@@ -5467,6 +5590,7 @@ static int syncWithMaster(void) {
     }
     server.master = createClient(fd);
     server.master->flags |= REDIS_MASTER;
+    server.master->authenticated = 1;
     server.replstate = REDIS_REPL_CONNECTED;
     return REDIS_OK;
 }
@@ -5560,8 +5684,8 @@ static void feedAppendOnlyFile(struct redisCommand *cmd, int dictid, robj **argv
         char seldb[64];
 
         snprintf(seldb,sizeof(seldb),"%d",dictid);
-        buf = sdscatprintf(buf,"*2\r\n$6\r\nSELECT\r\n$%d\r\n%s\r\n",
-            strlen(seldb),seldb);
+        buf = sdscatprintf(buf,"*2\r\n$6\r\nSELECT\r\n$%lu\r\n%s\r\n",
+            (unsigned long)strlen(seldb),seldb);
         server.appendseldb = dictid;
     }
 
@@ -5584,13 +5708,11 @@ static void feedAppendOnlyFile(struct redisCommand *cmd, int dictid, robj **argv
     for (j = 0; j < argc; j++) {
         robj *o = argv[j];
 
-        if (o->encoding != REDIS_ENCODING_RAW)
-            o = getDecodedObject(o);
-        buf = sdscatprintf(buf,"$%d\r\n",sdslen(o->ptr));
+        o = getDecodedObject(o);
+        buf = sdscatprintf(buf,"$%lu\r\n",(unsigned long)sdslen(o->ptr));
         buf = sdscatlen(buf,o->ptr,sdslen(o->ptr));
         buf = sdscatlen(buf,"\r\n",2);
-        if (o != argv[j])
-            decrRefCount(o);
+        decrRefCount(o);
     }
 
     /* Free the objects from the modified argv for EXPIREAT */
@@ -5616,6 +5738,14 @@ static void feedAppendOnlyFile(struct redisCommand *cmd, int dictid, robj **argv
          }
          exit(1);
     }
+    /* If a background append only file rewriting is in progress we want to
+     * accumulate the differences between the child DB and the current one
+     * in a buffer, so that when the child process will do its work we
+     * can append the differences to the new append only file. */
+    if (server.bgrewritechildpid != -1)
+        server.bgrewritebuf = sdscatlen(server.bgrewritebuf,buf,sdslen(buf));
+
+    sdsfree(buf);
     now = time(NULL);
     if (server.appendfsync == APPENDFSYNC_ALWAYS ||
         (server.appendfsync == APPENDFSYNC_EVERYSEC &&
@@ -5691,7 +5821,7 @@ int loadAppendOnlyFile(char *filename) {
             if (buf[0] != '$') goto fmterr;
             len = strtol(buf+1,NULL,10);
             argsds = sdsnewlen(NULL,len);
-            if (fread(argsds,len,1,fp) == 0) goto fmterr;
+            if (len && fread(argsds,len,1,fp) == 0) goto fmterr;
             argv[j] = createObject(REDIS_STRING,argsds);
             if (fread(buf,2,1,fp) == 0) goto fmterr; /* discard CRLF */
         }
@@ -5737,11 +5867,260 @@ fmterr:
     exit(1);
 }
 
+/* Write an object into a file in the bulk format $<count>\r\n<payload>\r\n */
+static int fwriteBulk(FILE *fp, robj *obj) {
+    char buf[128];
+    obj = getDecodedObject(obj);
+    snprintf(buf,sizeof(buf),"$%ld\r\n",(long)sdslen(obj->ptr));
+    if (fwrite(buf,strlen(buf),1,fp) == 0) goto err;
+    if (fwrite(obj->ptr,sdslen(obj->ptr),1,fp) == 0) goto err;
+    if (fwrite("\r\n",2,1,fp) == 0) goto err;
+    decrRefCount(obj);
+    return 1;
+err:
+    decrRefCount(obj);
+    return 0;
+}
+
+/* Write a double value in bulk format $<count>\r\n<payload>\r\n */
+static int fwriteBulkDouble(FILE *fp, double d) {
+    char buf[128], dbuf[128];
+
+    snprintf(dbuf,sizeof(dbuf),"%.17g\r\n",d);
+    snprintf(buf,sizeof(buf),"$%lu\r\n",(unsigned long)strlen(dbuf)-2);
+    if (fwrite(buf,strlen(buf),1,fp) == 0) return 0;
+    if (fwrite(dbuf,strlen(dbuf),1,fp) == 0) return 0;
+    return 1;
+}
+
+/* Write a long value in bulk format $<count>\r\n<payload>\r\n */
+static int fwriteBulkLong(FILE *fp, long l) {
+    char buf[128], lbuf[128];
+
+    snprintf(lbuf,sizeof(lbuf),"%ld\r\n",l);
+    snprintf(buf,sizeof(buf),"$%lu\r\n",(unsigned long)strlen(lbuf)-2);
+    if (fwrite(buf,strlen(buf),1,fp) == 0) return 0;
+    if (fwrite(lbuf,strlen(lbuf),1,fp) == 0) return 0;
+    return 1;
+}
+
+/* Write a sequence of commands able to fully rebuild the dataset into
+ * "filename". Used both by REWRITEAOF and BGREWRITEAOF. */
+static int rewriteAppendOnlyFile(char *filename) {
+    dictIterator *di = NULL;
+    dictEntry *de;
+    FILE *fp;
+    char tmpfile[256];
+    int j;
+    time_t now = time(NULL);
+
+    /* Note that we have to use a different temp name here compared to the
+     * one used by rewriteAppendOnlyFileBackground() function. */
+    snprintf(tmpfile,256,"temp-rewriteaof-%d.aof", (int) getpid());
+    fp = fopen(tmpfile,"w");
+    if (!fp) {
+        redisLog(REDIS_WARNING, "Failed rewriting the append only file: %s", strerror(errno));
+        return REDIS_ERR;
+    }
+    for (j = 0; j < server.dbnum; j++) {
+        char selectcmd[] = "*2\r\n$6\r\nSELECT\r\n";
+        redisDb *db = server.db+j;
+        dict *d = db->dict;
+        if (dictSize(d) == 0) continue;
+        di = dictGetIterator(d);
+        if (!di) {
+            fclose(fp);
+            return REDIS_ERR;
+        }
+
+        /* SELECT the new DB */
+        if (fwrite(selectcmd,sizeof(selectcmd)-1,1,fp) == 0) goto werr;
+        if (fwriteBulkLong(fp,j) == 0) goto werr;
+
+        /* Iterate this DB writing every entry */
+        while((de = dictNext(di)) != NULL) {
+            robj *key = dictGetEntryKey(de);
+            robj *o = dictGetEntryVal(de);
+            time_t expiretime = getExpire(db,key);
+
+            /* Save the key and associated value */
+            if (o->type == REDIS_STRING) {
+                /* Emit a SET command */
+                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;
+            } else if (o->type == REDIS_LIST) {
+                /* Emit the RPUSHes needed to rebuild the list */
+                list *list = o->ptr;
+                listNode *ln;
+
+                listRewind(list);
+                while((ln = listYield(list))) {
+                    char cmd[]="*3\r\n$5\r\nRPUSH\r\n";
+                    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;
+                }
+            } else if (o->type == REDIS_SET) {
+                /* Emit the SADDs needed to rebuild the set */
+                dict *set = o->ptr;
+                dictIterator *di = dictGetIterator(set);
+                dictEntry *de;
+
+                while((de = dictNext(di)) != NULL) {
+                    char cmd[]="*3\r\n$4\r\nSADD\r\n";
+                    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;
+                }
+                dictReleaseIterator(di);
+            } else if (o->type == REDIS_ZSET) {
+                /* Emit the ZADDs needed to rebuild the sorted set */
+                zset *zs = o->ptr;
+                dictIterator *di = dictGetIterator(zs->dict);
+                dictEntry *de;
+
+                while((de = dictNext(di)) != NULL) {
+                    char cmd[]="*4\r\n$4\r\nZADD\r\n";
+                    robj *eleobj = dictGetEntryKey(de);
+                    double *score = dictGetEntryVal(de);
+
+                    if (fwrite(cmd,sizeof(cmd)-1,1,fp) == 0) goto werr;
+                    if (fwriteBulk(fp,key) == 0) goto werr;
+                    if (fwriteBulkDouble(fp,*score) == 0) goto werr;
+                    if (fwriteBulk(fp,eleobj) == 0) goto werr;
+                }
+                dictReleaseIterator(di);
+            } else {
+                redisAssert(0 != 0);
+            }
+            /* Save the expire time */
+            if (expiretime != -1) {
+                char cmd[]="*3\r\n$6\r\nEXPIRE\r\n";
+                /* 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 (fwriteBulkLong(fp,expiretime) == 0) goto werr;
+            }
+        }
+        dictReleaseIterator(di);
+    }
+
+    /* Make sure data will not remain on the OS's output buffers */
+    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) {
+        redisLog(REDIS_WARNING,"Error moving temp append only file on the final destination: %s", strerror(errno));
+        unlink(tmpfile);
+        return REDIS_ERR;
+    }
+    redisLog(REDIS_NOTICE,"SYNC append only file rewrite performed");
+    return REDIS_OK;
+
+werr:
+    fclose(fp);
+    unlink(tmpfile);
+    redisLog(REDIS_WARNING,"Write error writing append only fileon disk: %s", strerror(errno));
+    if (di) dictReleaseIterator(di);
+    return REDIS_ERR;
+}
+
+/* This is how rewriting of the append only file in background works:
+ *
+ * 1) The user calls BGREWRITEAOF
+ * 2) Redis calls this function, that forks():
+ *    2a) the child rewrite the append only file in a temp file.
+ *    2b) the parent accumulates differences in server.bgrewritebuf.
+ * 3) When the child finished '2a' exists.
+ * 4) The parent will trap the exit code, if it's OK, will append the
+ *    data accumulated into server.bgrewritebuf into the temp file, and
+ *    finally will rename(2) the temp file in the actual file name.
+ *    The the new file is reopened as the new append only file. Profit!
+ */
+static int rewriteAppendOnlyFileBackground(void) {
+    pid_t childpid;
+
+    if (server.bgrewritechildpid != -1) return REDIS_ERR;
+    if ((childpid = fork()) == 0) {
+        /* Child */
+        char tmpfile[256];
+        close(server.fd);
+
+        snprintf(tmpfile,256,"temp-rewriteaof-bg-%d.aof", (int) getpid());
+        if (rewriteAppendOnlyFile(tmpfile) == REDIS_OK) {
+            exit(0);
+        } else {
+            exit(1);
+        }
+    } else {
+        /* Parent */
+        if (childpid == -1) {
+            redisLog(REDIS_WARNING,
+                "Can't rewrite append only file in background: fork: %s",
+                strerror(errno));
+            return REDIS_ERR;
+        }
+        redisLog(REDIS_NOTICE,
+            "Background append only file rewriting started by pid %d",childpid);
+        server.bgrewritechildpid = childpid;
+        /* 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
+         * with a SELECT statement and it will be safe to merge. */
+        server.appendseldb = -1;
+        return REDIS_OK;
+    }
+    return REDIS_OK; /* unreached */
+}
+
+static void bgrewriteaofCommand(redisClient *c) {
+    if (server.bgrewritechildpid != -1) {
+        addReplySds(c,sdsnew("-ERR background append only file rewriting already in progress\r\n"));
+        return;
+    }
+    if (rewriteAppendOnlyFileBackground() == REDIS_OK) {
+        char *status = "+Background append only file rewriting started\r\n";
+        addReplySds(c,sdsnew(status));
+    } else {
+        addReply(c,shared.err);
+    }
+}
+
+static void aofRemoveTempFile(pid_t childpid) {
+    char tmpfile[256];
+
+    snprintf(tmpfile,256,"temp-rewriteaof-bg-%d.aof", (int) childpid);
+    unlink(tmpfile);
+}
+
 /* ================================= Debugging ============================== */
 
 static void debugCommand(redisClient *c) {
     if (!strcasecmp(c->argv[1]->ptr,"segfault")) {
         *((char*)-1) = 'x';
+    } else if (!strcasecmp(c->argv[1]->ptr,"reload")) {
+        if (rdbSave(server.dbfilename) != REDIS_OK) {
+            addReply(c,shared.err);
+            return;
+        }
+        emptyDb();
+        if (rdbLoad(server.dbfilename) != REDIS_OK) {
+            addReply(c,shared.err);
+            return;
+        }
+        redisLog(REDIS_WARNING,"DB reloaded by DEBUG RELOAD");
+        addReply(c,shared.ok);
     } else if (!strcasecmp(c->argv[1]->ptr,"object") && c->argc == 3) {
         dictEntry *de = dictFind(c->db->dict,c->argv[2]);
         robj *key, *val;
@@ -5754,13 +6133,23 @@ static void debugCommand(redisClient *c) {
         val = dictGetEntryVal(de);
         addReplySds(c,sdscatprintf(sdsempty(),
             "+Key at:%p refcount:%d, value at:%p refcount:%d encoding:%d\r\n",
-                key, key->refcount, val, val->refcount, val->encoding));
+                (void*)key, key->refcount, (void*)val, val->refcount,
+                val->encoding));
     } else {
         addReplySds(c,sdsnew(
-            "-ERR Syntax error, try DEBUG [SEGFAULT|OBJECT <key>]\r\n"));
+            "-ERR Syntax error, try DEBUG [SEGFAULT|OBJECT <key>|RELOAD]\r\n"));
     }
 }
 
+static void _redisAssert(char *estr) {
+    redisLog(REDIS_WARNING,"=== ASSERTION FAILED ===");
+    redisLog(REDIS_WARNING,"==> %s\n",estr);
+#ifdef HAVE_BACKTRACE
+    redisLog(REDIS_WARNING,"(forcing SIGSEGV in order to print the stack trace)");
+    *((char*)-1) = 'x';
+#endif
+}
+
 /* =================================== Main! ================================ */
 
 #ifdef __linux__
@@ -5790,6 +6179,7 @@ static void daemonize(void) {
     FILE *fp;
 
     if (fork() != 0) exit(0); /* parent exits */
+    printf("New pid: %d\n", getpid());
     setsid(); /* create a new session */
 
     /* Every output goes to /dev/null. If Redis is daemonized but
@@ -5820,8 +6210,8 @@ int main(int argc, char **argv) {
     } 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'");
     }
-    initServer();
     if (server.daemonize) daemonize();
+    initServer();
     redisLog(REDIS_NOTICE,"Server started, Redis version " REDIS_VERSION);
 #ifdef __linux__
     linuxOvercommitMemoryWarning();
@@ -5852,7 +6242,11 @@ static void *getMcontextEip(ucontext_t *uc) {
 #elif defined(__dietlibc__)
     return (void*) uc->uc_mcontext.eip;
 #elif defined(__APPLE__) && !defined(MAC_OS_X_VERSION_10_6)
+  #if __x86_64__
+    return (void*) uc->uc_mcontext->__ss.__rip;
+  #else
     return (void*) uc->uc_mcontext->__ss.__eip;
+  #endif
 #elif defined(__APPLE__) && defined(MAC_OS_X_VERSION_10_6)
   #if defined(_STRUCT_X86_THREAD_STATE64) && !defined(__i386__)
     return (void*) uc->uc_mcontext->__ss.__rip;
@@ -5873,36 +6267,16 @@ static void segvHandler(int sig, siginfo_t *info, void *secret) {
     char **messages = NULL;
     int i, trace_size = 0;
     unsigned long offset=0;
-    time_t uptime = time(NULL)-server.stat_starttime;
     ucontext_t *uc = (ucontext_t*) secret;
+    sds infostring;
     REDIS_NOTUSED(info);
 
     redisLog(REDIS_WARNING,
         "======= Ooops! Redis %s got signal: -%d- =======", REDIS_VERSION, sig);
-    redisLog(REDIS_WARNING, "%s", sdscatprintf(sdsempty(),
-        "redis_version:%s; "
-        "uptime_in_seconds:%d; "
-        "connected_clients:%d; "
-        "connected_slaves:%d; "
-        "used_memory:%zu; "
-        "changes_since_last_save:%lld; "
-        "bgsave_in_progress:%d; "
-        "last_save_time:%d; "
-        "total_connections_received:%lld; "
-        "total_commands_processed:%lld; "
-        "role:%s;"
-        ,REDIS_VERSION,
-        uptime,
-        listLength(server.clients)-listLength(server.slaves),
-        listLength(server.slaves),
-        server.usedmemory,
-        server.dirty,
-        server.bgsaveinprogress,
-        server.lastsave,
-        server.stat_numconnections,
-        server.stat_numcommands,
-        server.masterhost == NULL ? "master" : "slave"
-    ));
+    infostring = genRedisInfoString();
+    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 */
@@ -5921,7 +6295,7 @@ static void segvHandler(int sig, siginfo_t *info, void *secret) {
             redisLog(REDIS_WARNING,"%d redis-server %p %s + %d", i, trace[i], fn, (unsigned int)offset);
         }
     }
-    free(messages);
+    // free(messages); Don't call free() with possibly corrupted memory.
     exit(0);
 }