X-Git-Url: https://git.saurik.com/redis.git/blobdiff_plain/d4a3cfed9c95e0ca5f8bcc771f8844ad17895c69..3e8fcb6d031b092677191ffdd4808c4eb4975270:/src/aof.c?ds=sidebyside

diff --git a/src/aof.c b/src/aof.c
index 4a463bde..64cd76d3 100644
--- a/src/aof.c
+++ b/src/aof.c
@@ -19,42 +19,48 @@ void aof_background_fsync(int fd) {
 /* Called when the user switches from "appendonly yes" to "appendonly no"
  * at runtime using the CONFIG command. */
 void stopAppendOnly(void) {
+    redisAssert(server.aof_state != REDIS_AOF_OFF);
     flushAppendOnlyFile(1);
-    aof_fsync(server.appendfd);
-    close(server.appendfd);
+    aof_fsync(server.aof_fd);
+    close(server.aof_fd);
 
-    server.appendfd = -1;
-    server.appendseldb = -1;
-    server.appendonly = 0;
+    server.aof_fd = -1;
+    server.aof_selected_db = -1;
+    server.aof_state = REDIS_AOF_OFF;
     /* rewrite operation in progress? kill it, wait child exit */
-    if (server.bgrewritechildpid != -1) {
+    if (server.aof_child_pid != -1) {
         int statloc;
 
-        if (kill(server.bgrewritechildpid,SIGKILL) != -1)
+        redisLog(REDIS_NOTICE,"Killing running AOF rewrite child: %ld",
+            (long) server.aof_child_pid);
+        if (kill(server.aof_child_pid,SIGKILL) != -1)
             wait3(&statloc,0,NULL);
         /* reset the buffer accumulating changes while the child saves */
-        sdsfree(server.bgrewritebuf);
-        server.bgrewritebuf = sdsempty();
-        server.bgrewritechildpid = -1;
+        sdsfree(server.aof_rewrite_buf);
+        server.aof_rewrite_buf = sdsempty();
+        aofRemoveTempFile(server.aof_child_pid);
+        server.aof_child_pid = -1;
     }
 }
 
 /* Called when the user switches from "appendonly no" to "appendonly yes"
  * at runtime using the CONFIG command. */
 int startAppendOnly(void) {
-    server.appendonly = 1;
-    server.lastfsync = time(NULL);
-    server.appendfd = open(server.appendfilename,O_WRONLY|O_APPEND|O_CREAT,0644);
-    if (server.appendfd == -1) {
-        redisLog(REDIS_WARNING,"Used tried to switch on AOF via CONFIG, but I can't open the AOF file: %s",strerror(errno));
+    server.aof_last_fsync = time(NULL);
+    server.aof_fd = open(server.aof_filename,O_WRONLY|O_APPEND|O_CREAT,0644);
+    redisAssert(server.aof_state == REDIS_AOF_OFF);
+    if (server.aof_fd == -1) {
+        redisLog(REDIS_WARNING,"Redis needs to enable the AOF but can't open the append only file: %s",strerror(errno));
         return REDIS_ERR;
     }
     if (rewriteAppendOnlyFileBackground() == REDIS_ERR) {
-        server.appendonly = 0;
-        close(server.appendfd);
-        redisLog(REDIS_WARNING,"User tried turning on AOF with CONFIG SET but I can't trigger a background AOF rewrite operation. Check the above logs for more info about the error.");
+        close(server.aof_fd);
+        redisLog(REDIS_WARNING,"Redis needs to enable the AOF but can't trigger a background AOF rewrite operation. Check the above logs for more info about the error.");
         return REDIS_ERR;
     }
+    /* We correctly switched on AOF, now wait for the rerwite to be complete
+     * in order to append data on disk. */
+    server.aof_state = REDIS_AOF_WAIT_REWRITE;
     return REDIS_OK;
 }
 
@@ -80,12 +86,12 @@ void flushAppendOnlyFile(int force) {
     ssize_t nwritten;
     int sync_in_progress = 0;
 
-    if (sdslen(server.aofbuf) == 0) return;
+    if (sdslen(server.aof_buf) == 0) return;
 
-    if (server.appendfsync == APPENDFSYNC_EVERYSEC)
+    if (server.aof_fsync == AOF_FSYNC_EVERYSEC)
         sync_in_progress = bioPendingJobsOfType(REDIS_BIO_AOF_FSYNC) != 0;
 
-    if (server.appendfsync == APPENDFSYNC_EVERYSEC && !force) {
+    if (server.aof_fsync == AOF_FSYNC_EVERYSEC && !force) {
         /* With this append fsync policy we do background fsyncing.
          * If the fsync is still in progress we can try to delay
          * the write for a couple of seconds. */
@@ -114,45 +120,50 @@ void flushAppendOnlyFile(int force) {
      * While this will save us against the server being killed I don't think
      * there is much to do about the whole server stopping for power problems
      * or alike */
-    nwritten = write(server.appendfd,server.aofbuf,sdslen(server.aofbuf));
-    if (nwritten != (signed)sdslen(server.aofbuf)) {
+    nwritten = write(server.aof_fd,server.aof_buf,sdslen(server.aof_buf));
+    if (nwritten != (signed)sdslen(server.aof_buf)) {
         /* Ooops, we are in troubles. The best thing to do for now is
          * aborting instead of giving the illusion that everything is
          * working as expected. */
         if (nwritten == -1) {
             redisLog(REDIS_WARNING,"Exiting on error writing to the append-only file: %s",strerror(errno));
         } else {
-            redisLog(REDIS_WARNING,"Exiting on short write while writing to the append-only file: %s",strerror(errno));
+            redisLog(REDIS_WARNING,"Exiting on short write while writing to "
+                                   "the append-only file: %s (nwritten=%ld, "
+                                   "expected=%ld)",
+                                   strerror(errno),
+                                   (long)nwritten,
+                                   (long)sdslen(server.aof_buf));
         }
         exit(1);
     }
-    server.appendonly_current_size += nwritten;
+    server.aof_current_size += nwritten;
 
     /* Re-use AOF buffer when it is small enough. The maximum comes from the
      * arena size of 4k minus some overhead (but is otherwise arbitrary). */
-    if ((sdslen(server.aofbuf)+sdsavail(server.aofbuf)) < 4000) {
-        sdsclear(server.aofbuf);
+    if ((sdslen(server.aof_buf)+sdsavail(server.aof_buf)) < 4000) {
+        sdsclear(server.aof_buf);
     } else {
-        sdsfree(server.aofbuf);
-        server.aofbuf = sdsempty();
+        sdsfree(server.aof_buf);
+        server.aof_buf = sdsempty();
     }
 
     /* Don't fsync if no-appendfsync-on-rewrite is set to yes and there are
      * children doing I/O in the background. */
-    if (server.no_appendfsync_on_rewrite &&
-        (server.bgrewritechildpid != -1 || server.bgsavechildpid != -1))
+    if (server.aof_no_fsync_on_rewrite &&
+        (server.aof_child_pid != -1 || server.rdb_child_pid != -1))
             return;
 
     /* Perform the fsync if needed. */
-    if (server.appendfsync == APPENDFSYNC_ALWAYS) {
+    if (server.aof_fsync == AOF_FSYNC_ALWAYS) {
         /* aof_fsync is defined as fdatasync() for Linux in order to avoid
          * flushing metadata. */
-        aof_fsync(server.appendfd); /* Let's try to get this data on the disk */
-        server.lastfsync = server.unixtime;
-    } else if ((server.appendfsync == APPENDFSYNC_EVERYSEC &&
-                server.unixtime > server.lastfsync)) {
-        if (!sync_in_progress) aof_background_fsync(server.appendfd);
-        server.lastfsync = server.unixtime;
+        aof_fsync(server.aof_fd); /* Let's try to get this data on the disk */
+        server.aof_last_fsync = server.unixtime;
+    } else if ((server.aof_fsync == AOF_FSYNC_EVERYSEC &&
+                server.unixtime > server.aof_last_fsync)) {
+        if (!sync_in_progress) aof_background_fsync(server.aof_fd);
+        server.aof_last_fsync = server.unixtime;
     }
 }
 
@@ -224,13 +235,13 @@ void feedAppendOnlyFile(struct redisCommand *cmd, int dictid, robj **argv, int a
 
     /* The DB this command was targetting is not the same as the last command
      * we appendend. To issue a SELECT command is needed. */
-    if (dictid != server.appendseldb) {
+    if (dictid != server.aof_selected_db) {
         char seldb[64];
 
         snprintf(seldb,sizeof(seldb),"%d",dictid);
         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;
+        server.aof_selected_db = dictid;
     }
 
     if (cmd->proc == expireCommand || cmd->proc == pexpireCommand ||
@@ -255,14 +266,15 @@ void feedAppendOnlyFile(struct redisCommand *cmd, int dictid, robj **argv, int a
     /* Append to the AOF buffer. This will be flushed on disk just before
      * of re-entering the event loop, so before the client will get a
      * positive reply about the operation performed. */
-    server.aofbuf = sdscatlen(server.aofbuf,buf,sdslen(buf));
+    if (server.aof_state == REDIS_AOF_ON)
+        server.aof_buf = sdscatlen(server.aof_buf,buf,sdslen(buf));
 
     /* 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));
+    if (server.aof_child_pid != -1)
+        server.aof_rewrite_buf = sdscatlen(server.aof_rewrite_buf,buf,sdslen(buf));
 
     sdsfree(buf);
 }
@@ -283,6 +295,8 @@ struct redisClient *createFakeClient(void) {
      * so that Redis will not try to send replies to this client. */
     c->replstate = REDIS_REPL_WAIT_BGSAVE_START;
     c->reply = listCreate();
+    c->reply_bytes = 0;
+    c->obuf_soft_limit_reached_time = 0;
     c->watched_keys = listCreate();
     listSetFreeMethod(c->reply,decrRefCount);
     listSetDupMethod(c->reply,dupClientReplyValue);
@@ -305,11 +319,11 @@ int loadAppendOnlyFile(char *filename) {
     struct redisClient *fakeClient;
     FILE *fp = fopen(filename,"r");
     struct redis_stat sb;
-    int appendonly = server.appendonly;
+    int old_aof_state = server.aof_state;
     long loops = 0;
 
     if (fp && redis_fstat(fileno(fp),&sb) != -1 && sb.st_size == 0) {
-        server.appendonly_current_size = 0;
+        server.aof_current_size = 0;
         fclose(fp);
         return REDIS_ERR;
     }
@@ -321,7 +335,7 @@ int loadAppendOnlyFile(char *filename) {
 
     /* Temporarily disable AOF, to prevent EXEC from feeding a MULTI
      * to the same file we're about to read. */
-    server.appendonly = 0;
+    server.aof_state = REDIS_AOF_OFF;
 
     fakeClient = createFakeClient();
     startLoading(fp);
@@ -390,10 +404,10 @@ int loadAppendOnlyFile(char *filename) {
 
     fclose(fp);
     freeFakeClient(fakeClient);
-    server.appendonly = appendonly;
+    server.aof_state = old_aof_state;
     stopLoading();
     aofUpdateCurrentSize();
-    server.auto_aofrewrite_base_size = server.appendonly_current_size;
+    server.aof_rewrite_base_size = server.aof_current_size;
     return REDIS_OK;
 
 readerr:
@@ -422,8 +436,244 @@ int rioWriteBulkObject(rio *r, robj *obj) {
     }
 }
 
+/* Emit the commands needed to rebuild a list object.
+ * The function returns 0 on error, 1 on success. */
+int rewriteListObject(rio *r, robj *key, robj *o) {
+    long long count = 0, items = listTypeLength(o);
+
+    if (o->encoding == REDIS_ENCODING_ZIPLIST) {
+        unsigned char *zl = o->ptr;
+        unsigned char *p = ziplistIndex(zl,0);
+        unsigned char *vstr;
+        unsigned int vlen;
+        long long vlong;
+
+        while(ziplistGet(p,&vstr,&vlen,&vlong)) {
+            if (count == 0) {
+                int cmd_items = (items > REDIS_AOF_REWRITE_ITEMS_PER_CMD) ?
+                    REDIS_AOF_REWRITE_ITEMS_PER_CMD : items;
+
+                if (rioWriteBulkCount(r,'*',2+cmd_items) == 0) return 0;
+                if (rioWriteBulkString(r,"RPUSH",5) == 0) return 0;
+                if (rioWriteBulkObject(r,key) == 0) return 0;
+            }
+            if (vstr) {
+                if (rioWriteBulkString(r,(char*)vstr,vlen) == 0) return 0;
+            } else {
+                if (rioWriteBulkLongLong(r,vlong) == 0) return 0;
+            }
+            p = ziplistNext(zl,p);
+            if (++count == REDIS_AOF_REWRITE_ITEMS_PER_CMD) count = 0;
+            items--;
+        }
+    } else if (o->encoding == REDIS_ENCODING_LINKEDLIST) {
+        list *list = o->ptr;
+        listNode *ln;
+        listIter li;
+
+        listRewind(list,&li);
+        while((ln = listNext(&li))) {
+            robj *eleobj = listNodeValue(ln);
+
+            if (count == 0) {
+                int cmd_items = (items > REDIS_AOF_REWRITE_ITEMS_PER_CMD) ?
+                    REDIS_AOF_REWRITE_ITEMS_PER_CMD : items;
+
+                if (rioWriteBulkCount(r,'*',2+cmd_items) == 0) return 0;
+                if (rioWriteBulkString(r,"RPUSH",5) == 0) return 0;
+                if (rioWriteBulkObject(r,key) == 0) return 0;
+            }
+            if (rioWriteBulkObject(r,eleobj) == 0) return 0;
+            if (++count == REDIS_AOF_REWRITE_ITEMS_PER_CMD) count = 0;
+            items--;
+        }
+    } else {
+        redisPanic("Unknown list encoding");
+    }
+    return 1;
+}
+
+/* Emit the commands needed to rebuild a set object.
+ * The function returns 0 on error, 1 on success. */
+int rewriteSetObject(rio *r, robj *key, robj *o) {
+    long long count = 0, items = setTypeSize(o);
+
+    if (o->encoding == REDIS_ENCODING_INTSET) {
+        int ii = 0;
+        int64_t llval;
+
+        while(intsetGet(o->ptr,ii++,&llval)) {
+            if (count == 0) {
+                int cmd_items = (items > REDIS_AOF_REWRITE_ITEMS_PER_CMD) ?
+                    REDIS_AOF_REWRITE_ITEMS_PER_CMD : items;
+
+                if (rioWriteBulkCount(r,'*',2+cmd_items) == 0) return 0;
+                if (rioWriteBulkString(r,"SADD",4) == 0) return 0;
+                if (rioWriteBulkObject(r,key) == 0) return 0;
+            }
+            if (rioWriteBulkLongLong(r,llval) == 0) return 0;
+            if (++count == REDIS_AOF_REWRITE_ITEMS_PER_CMD) count = 0;
+            items--;
+        }
+    } else if (o->encoding == REDIS_ENCODING_HT) {
+        dictIterator *di = dictGetIterator(o->ptr);
+        dictEntry *de;
+
+        while((de = dictNext(di)) != NULL) {
+            robj *eleobj = dictGetKey(de);
+            if (count == 0) {
+                int cmd_items = (items > REDIS_AOF_REWRITE_ITEMS_PER_CMD) ?
+                    REDIS_AOF_REWRITE_ITEMS_PER_CMD : items;
+
+                if (rioWriteBulkCount(r,'*',2+cmd_items) == 0) return 0;
+                if (rioWriteBulkString(r,"SADD",4) == 0) return 0;
+                if (rioWriteBulkObject(r,key) == 0) return 0;
+            }
+            if (rioWriteBulkObject(r,eleobj) == 0) return 0;
+            if (++count == REDIS_AOF_REWRITE_ITEMS_PER_CMD) count = 0;
+            items--;
+        }
+        dictReleaseIterator(di);
+    } else {
+        redisPanic("Unknown set encoding");
+    }
+    return 1;
+}
+
+/* Emit the commands needed to rebuild a sorted set object.
+ * The function returns 0 on error, 1 on success. */
+int rewriteSortedSetObject(rio *r, robj *key, robj *o) {
+    long long count = 0, items = zsetLength(o);
+
+    if (o->encoding == REDIS_ENCODING_ZIPLIST) {
+        unsigned char *zl = o->ptr;
+        unsigned char *eptr, *sptr;
+        unsigned char *vstr;
+        unsigned int vlen;
+        long long vll;
+        double score;
+
+        eptr = ziplistIndex(zl,0);
+        redisAssert(eptr != NULL);
+        sptr = ziplistNext(zl,eptr);
+        redisAssert(sptr != NULL);
+
+        while (eptr != NULL) {
+            redisAssert(ziplistGet(eptr,&vstr,&vlen,&vll));
+            score = zzlGetScore(sptr);
+
+            if (count == 0) {
+                int cmd_items = (items > REDIS_AOF_REWRITE_ITEMS_PER_CMD) ?
+                    REDIS_AOF_REWRITE_ITEMS_PER_CMD : items;
+
+                if (rioWriteBulkCount(r,'*',2+cmd_items*2) == 0) return 0;
+                if (rioWriteBulkString(r,"ZADD",4) == 0) return 0;
+                if (rioWriteBulkObject(r,key) == 0) return 0;
+            }
+            if (rioWriteBulkDouble(r,score) == 0) return 0;
+            if (vstr != NULL) {
+                if (rioWriteBulkString(r,(char*)vstr,vlen) == 0) return 0;
+            } else {
+                if (rioWriteBulkLongLong(r,vll) == 0) return 0;
+            }
+            zzlNext(zl,&eptr,&sptr);
+            if (++count == REDIS_AOF_REWRITE_ITEMS_PER_CMD) count = 0;
+            items--;
+        }
+    } else if (o->encoding == REDIS_ENCODING_SKIPLIST) {
+        zset *zs = o->ptr;
+        dictIterator *di = dictGetIterator(zs->dict);
+        dictEntry *de;
+
+        while((de = dictNext(di)) != NULL) {
+            robj *eleobj = dictGetKey(de);
+            double *score = dictGetVal(de);
+
+            if (count == 0) {
+                int cmd_items = (items > REDIS_AOF_REWRITE_ITEMS_PER_CMD) ?
+                    REDIS_AOF_REWRITE_ITEMS_PER_CMD : items;
+
+                if (rioWriteBulkCount(r,'*',2+cmd_items*2) == 0) return 0;
+                if (rioWriteBulkString(r,"ZADD",4) == 0) return 0;
+                if (rioWriteBulkObject(r,key) == 0) return 0;
+            }
+            if (rioWriteBulkDouble(r,*score) == 0) return 0;
+            if (rioWriteBulkObject(r,eleobj) == 0) return 0;
+            if (++count == REDIS_AOF_REWRITE_ITEMS_PER_CMD) count = 0;
+            items--;
+        }
+        dictReleaseIterator(di);
+    } else {
+        redisPanic("Unknown sorted zset encoding");
+    }
+    return 1;
+}
+
+/* Write either the key or the value of the currently selected item of an hash.
+ * The 'hi' argument passes a valid Redis hash iterator.
+ * The 'what' filed specifies if to write a key or a value and can be
+ * either REDIS_HASH_KEY or REDIS_HASH_VALUE.
+ *
+ * The function returns 0 on error, non-zero on success. */
+static int rioWriteHashIteratorCursor(rio *r, hashTypeIterator *hi, int what) {
+    if (hi->encoding == REDIS_ENCODING_ZIPLIST) {
+        unsigned char *vstr = NULL;
+        unsigned int vlen = UINT_MAX;
+        long long vll = LLONG_MAX;
+
+        hashTypeCurrentFromZiplist(hi, what, &vstr, &vlen, &vll);
+        if (vstr) {
+            return rioWriteBulkString(r, (char*)vstr, vlen);
+        } else {
+            return rioWriteBulkLongLong(r, vll);
+        }
+
+    } else if (hi->encoding == REDIS_ENCODING_HT) {
+        robj *value;
+
+        hashTypeCurrentFromHashTable(hi, what, &value);
+        return rioWriteBulkObject(r, value);
+    }
+
+    redisPanic("Unknown hash encoding");
+    return 0;
+}
+
+/* Emit the commands needed to rebuild a hash object.
+ * The function returns 0 on error, 1 on success. */
+int rewriteHashObject(rio *r, robj *key, robj *o) {
+    hashTypeIterator *hi;
+    long long count = 0, items = hashTypeLength(o);
+
+    hi = hashTypeInitIterator(o);
+    while (hashTypeNext(hi) != REDIS_ERR) {
+        if (count == 0) {
+            int cmd_items = (items > REDIS_AOF_REWRITE_ITEMS_PER_CMD) ?
+                REDIS_AOF_REWRITE_ITEMS_PER_CMD : items;
+
+            if (rioWriteBulkCount(r,'*',2+cmd_items*2) == 0) return 0;
+            if (rioWriteBulkString(r,"HMSET",5) == 0) return 0;
+            if (rioWriteBulkObject(r,key) == 0) return 0;
+        }
+
+        if (rioWriteHashIteratorCursor(r, hi, REDIS_HASH_KEY) == 0) return 0;
+        if (rioWriteHashIteratorCursor(r, hi, REDIS_HASH_VALUE) == 0) return 0;
+        if (++count == REDIS_AOF_REWRITE_ITEMS_PER_CMD) count = 0;
+        items--;
+    }
+
+    hashTypeReleaseIterator(hi);
+
+    return 1;
+}
+
 /* Write a sequence of commands able to fully rebuild the dataset into
- * "filename". Used both by REWRITEAOF and BGREWRITEAOF. */
+ * "filename". Used both by REWRITEAOF and BGREWRITEAOF.
+ *
+ * In order to minimize the number of commands needed in the rewritten
+ * log Redis uses variadic commands when possible, such as RPUSH, SADD
+ * and ZADD. However at max REDIS_AOF_REWRITE_ITEMS_PER_CMD items per time
+ * are inserted using a single command. */
 int rewriteAppendOnlyFile(char *filename) {
     dictIterator *di = NULL;
     dictEntry *de;
@@ -438,7 +688,7 @@ int rewriteAppendOnlyFile(char *filename) {
     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));
+        redisLog(REDIS_WARNING, "Opening the temp file for AOF rewrite in rewriteAppendOnlyFile(): %s", strerror(errno));
         return REDIS_ERR;
     }
 
@@ -479,151 +729,13 @@ int rewriteAppendOnlyFile(char *filename) {
                 if (rioWriteBulkObject(&aof,&key) == 0) goto werr;
                 if (rioWriteBulkObject(&aof,o) == 0) goto werr;
             } else if (o->type == REDIS_LIST) {
-                /* Emit the RPUSHes needed to rebuild the list */
-                char cmd[]="*3\r\n$5\r\nRPUSH\r\n";
-                if (o->encoding == REDIS_ENCODING_ZIPLIST) {
-                    unsigned char *zl = o->ptr;
-                    unsigned char *p = ziplistIndex(zl,0);
-                    unsigned char *vstr;
-                    unsigned int vlen;
-                    long long vlong;
-
-                    while(ziplistGet(p,&vstr,&vlen,&vlong)) {
-                        if (rioWrite(&aof,cmd,sizeof(cmd)-1) == 0) goto werr;
-                        if (rioWriteBulkObject(&aof,&key) == 0) goto werr;
-                        if (vstr) {
-                            if (rioWriteBulkString(&aof,(char*)vstr,vlen) == 0)
-                                goto werr;
-                        } else {
-                            if (rioWriteBulkLongLong(&aof,vlong) == 0)
-                                goto werr;
-                        }
-                        p = ziplistNext(zl,p);
-                    }
-                } else if (o->encoding == REDIS_ENCODING_LINKEDLIST) {
-                    list *list = o->ptr;
-                    listNode *ln;
-                    listIter li;
-
-                    listRewind(list,&li);
-                    while((ln = listNext(&li))) {
-                        robj *eleobj = listNodeValue(ln);
-
-                        if (rioWrite(&aof,cmd,sizeof(cmd)-1) == 0) goto werr;
-                        if (rioWriteBulkObject(&aof,&key) == 0) goto werr;
-                        if (rioWriteBulkObject(&aof,eleobj) == 0) goto werr;
-                    }
-                } else {
-                    redisPanic("Unknown list encoding");
-                }
+                if (rewriteListObject(&aof,&key,o) == 0) goto werr;
             } else if (o->type == REDIS_SET) {
-                char cmd[]="*3\r\n$4\r\nSADD\r\n";
-
-                /* Emit the SADDs needed to rebuild the set */
-                if (o->encoding == REDIS_ENCODING_INTSET) {
-                    int ii = 0;
-                    int64_t llval;
-                    while(intsetGet(o->ptr,ii++,&llval)) {
-                        if (rioWrite(&aof,cmd,sizeof(cmd)-1) == 0) goto werr;
-                        if (rioWriteBulkObject(&aof,&key) == 0) goto werr;
-                        if (rioWriteBulkLongLong(&aof,llval) == 0) goto werr;
-                    }
-                } else if (o->encoding == REDIS_ENCODING_HT) {
-                    dictIterator *di = dictGetIterator(o->ptr);
-                    dictEntry *de;
-                    while((de = dictNext(di)) != NULL) {
-                        robj *eleobj = dictGetKey(de);
-                        if (rioWrite(&aof,cmd,sizeof(cmd)-1) == 0) goto werr;
-                        if (rioWriteBulkObject(&aof,&key) == 0) goto werr;
-                        if (rioWriteBulkObject(&aof,eleobj) == 0) goto werr;
-                    }
-                    dictReleaseIterator(di);
-                } else {
-                    redisPanic("Unknown set encoding");
-                }
+                if (rewriteSetObject(&aof,&key,o) == 0) goto werr;
             } else if (o->type == REDIS_ZSET) {
-                /* Emit the ZADDs needed to rebuild the sorted set */
-                char cmd[]="*4\r\n$4\r\nZADD\r\n";
-
-                if (o->encoding == REDIS_ENCODING_ZIPLIST) {
-                    unsigned char *zl = o->ptr;
-                    unsigned char *eptr, *sptr;
-                    unsigned char *vstr;
-                    unsigned int vlen;
-                    long long vll;
-                    double score;
-
-                    eptr = ziplistIndex(zl,0);
-                    redisAssert(eptr != NULL);
-                    sptr = ziplistNext(zl,eptr);
-                    redisAssert(sptr != NULL);
-
-                    while (eptr != NULL) {
-                        redisAssert(ziplistGet(eptr,&vstr,&vlen,&vll));
-                        score = zzlGetScore(sptr);
-
-                        if (rioWrite(&aof,cmd,sizeof(cmd)-1) == 0) goto werr;
-                        if (rioWriteBulkObject(&aof,&key) == 0) goto werr;
-                        if (rioWriteBulkDouble(&aof,score) == 0) goto werr;
-                        if (vstr != NULL) {
-                            if (rioWriteBulkString(&aof,(char*)vstr,vlen) == 0)
-                                goto werr;
-                        } else {
-                            if (rioWriteBulkLongLong(&aof,vll) == 0)
-                                goto werr;
-                        }
-                        zzlNext(zl,&eptr,&sptr);
-                    }
-                } else if (o->encoding == REDIS_ENCODING_SKIPLIST) {
-                    zset *zs = o->ptr;
-                    dictIterator *di = dictGetIterator(zs->dict);
-                    dictEntry *de;
-
-                    while((de = dictNext(di)) != NULL) {
-                        robj *eleobj = dictGetKey(de);
-                        double *score = dictGetVal(de);
-
-                        if (rioWrite(&aof,cmd,sizeof(cmd)-1) == 0) goto werr;
-                        if (rioWriteBulkObject(&aof,&key) == 0) goto werr;
-                        if (rioWriteBulkDouble(&aof,*score) == 0) goto werr;
-                        if (rioWriteBulkObject(&aof,eleobj) == 0) goto werr;
-                    }
-                    dictReleaseIterator(di);
-                } else {
-                    redisPanic("Unknown sorted set encoding");
-                }
+                if (rewriteSortedSetObject(&aof,&key,o) == 0) goto werr;
             } 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 (rioWrite(&aof,cmd,sizeof(cmd)-1) == 0) goto werr;
-                        if (rioWriteBulkObject(&aof,&key) == 0) goto werr;
-                        if (rioWriteBulkString(&aof,(char*)field,flen) == 0)
-                            goto werr;
-                        if (rioWriteBulkString(&aof,(char*)val,vlen) == 0)
-                            goto werr;
-                    }
-                } else {
-                    dictIterator *di = dictGetIterator(o->ptr);
-                    dictEntry *de;
-
-                    while((de = dictNext(di)) != NULL) {
-                        robj *field = dictGetKey(de);
-                        robj *val = dictGetVal(de);
-
-                        if (rioWrite(&aof,cmd,sizeof(cmd)-1) == 0) goto werr;
-                        if (rioWriteBulkObject(&aof,&key) == 0) goto werr;
-                        if (rioWriteBulkObject(&aof,field) == 0) goto werr;
-                        if (rioWriteBulkObject(&aof,val) == 0) goto werr;
-                    }
-                    dictReleaseIterator(di);
-                }
+                if (rewriteHashObject(&aof,&key,o) == 0) goto werr;
             } else {
                 redisPanic("Unknown object type");
             }
@@ -668,10 +780,10 @@ werr:
  * 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.
+ *    2b) the parent accumulates differences in server.aof_rewrite_buf.
  * 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
+ *    data accumulated into server.aof_rewrite_buf 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!
  */
@@ -679,7 +791,7 @@ int rewriteAppendOnlyFileBackground(void) {
     pid_t childpid;
     long long start;
 
-    if (server.bgrewritechildpid != -1) return REDIS_ERR;
+    if (server.aof_child_pid != -1) return REDIS_ERR;
     start = ustime();
     if ((childpid = fork()) == 0) {
         char tmpfile[256];
@@ -704,24 +816,24 @@ int rewriteAppendOnlyFileBackground(void) {
         }
         redisLog(REDIS_NOTICE,
             "Background append only file rewriting started by pid %d",childpid);
-        server.aofrewrite_scheduled = 0;
-        server.bgrewritechildpid = childpid;
+        server.aof_rewrite_scheduled = 0;
+        server.aof_child_pid = childpid;
         updateDictResizePolicy();
         /* We set appendseldb to -1 in order to force the next call to the
          * feedAppendOnlyFile() to issue a SELECT command, so the differences
-         * accumulated by the parent into server.bgrewritebuf will start
+         * accumulated by the parent into server.aof_rewrite_buf will start
          * with a SELECT statement and it will be safe to merge. */
-        server.appendseldb = -1;
+        server.aof_selected_db = -1;
         return REDIS_OK;
     }
     return REDIS_OK; /* unreached */
 }
 
 void bgrewriteaofCommand(redisClient *c) {
-    if (server.bgrewritechildpid != -1) {
+    if (server.aof_child_pid != -1) {
         addReplyError(c,"Background append only file rewriting already in progress");
-    } else if (server.bgsavechildpid != -1) {
-        server.aofrewrite_scheduled = 1;
+    } else if (server.rdb_child_pid != -1) {
+        server.aof_rewrite_scheduled = 1;
         addReplyStatus(c,"Background append only file rewriting scheduled");
     } else if (rewriteAppendOnlyFileBackground() == REDIS_OK) {
         addReplyStatus(c,"Background append only file rewriting started");
@@ -737,18 +849,18 @@ void aofRemoveTempFile(pid_t childpid) {
     unlink(tmpfile);
 }
 
-/* Update the server.appendonly_current_size filed explicitly using stat(2)
+/* Update the server.aof_current_size filed explicitly using stat(2)
  * to check the size of the file. This is useful after a rewrite or after
  * a restart, normally the size is updated just adding the write length
- * to the current lenght, that is much faster. */
+ * to the current length, that is much faster. */
 void aofUpdateCurrentSize(void) {
     struct redis_stat sb;
 
-    if (redis_fstat(server.appendfd,&sb) == -1) {
-        redisLog(REDIS_WARNING,"Unable to check the AOF length: %s",
+    if (redis_fstat(server.aof_fd,&sb) == -1) {
+        redisLog(REDIS_WARNING,"Unable to obtain the AOF file length. stat: %s",
             strerror(errno));
     } else {
-        server.appendonly_current_size = sb.st_size;
+        server.aof_current_size = sb.st_size;
     }
 }
 
@@ -767,7 +879,7 @@ void backgroundRewriteDoneHandler(int exitcode, int bysignal) {
         /* Flush the differences accumulated by the parent to the
          * rewritten AOF. */
         snprintf(tmpfile,256,"temp-rewriteaof-bg-%d.aof",
-            (int)server.bgrewritechildpid);
+            (int)server.aof_child_pid);
         newfd = open(tmpfile,O_WRONLY|O_APPEND);
         if (newfd == -1) {
             redisLog(REDIS_WARNING,
@@ -775,8 +887,8 @@ void backgroundRewriteDoneHandler(int exitcode, int bysignal) {
             goto cleanup;
         }
 
-        nwritten = write(newfd,server.bgrewritebuf,sdslen(server.bgrewritebuf));
-        if (nwritten != (signed)sdslen(server.bgrewritebuf)) {
+        nwritten = write(newfd,server.aof_rewrite_buf,sdslen(server.aof_rewrite_buf));
+        if (nwritten != (signed)sdslen(server.aof_rewrite_buf)) {
             if (nwritten == -1) {
                 redisLog(REDIS_WARNING,
                     "Error trying to flush the parent diff to the rewritten AOF: %s", strerror(errno));
@@ -818,13 +930,13 @@ void backgroundRewriteDoneHandler(int exitcode, int bysignal) {
          * guarantee atomicity for this switch has already happened by then, so
          * we don't care what the outcome or duration of that close operation
          * is, as long as the file descriptor is released again. */
-        if (server.appendfd == -1) {
+        if (server.aof_fd == -1) {
             /* AOF disabled */
 
              /* Don't care if this fails: oldfd will be -1 and we handle that.
               * One notable case of -1 return is if the old file does
               * not exist. */
-             oldfd = open(server.appendfilename,O_RDONLY|O_NONBLOCK);
+             oldfd = open(server.aof_filename,O_RDONLY|O_NONBLOCK);
         } else {
             /* AOF enabled */
             oldfd = -1; /* We'll set this to the current AOF filedes later. */
@@ -832,37 +944,40 @@ void backgroundRewriteDoneHandler(int exitcode, int bysignal) {
 
         /* Rename the temporary file. This will not unlink the target file if
          * it exists, because we reference it with "oldfd". */
-        if (rename(tmpfile,server.appendfilename) == -1) {
+        if (rename(tmpfile,server.aof_filename) == -1) {
             redisLog(REDIS_WARNING,
-                "Error trying to rename the temporary AOF: %s", strerror(errno));
+                "Error trying to rename the temporary AOF file: %s", strerror(errno));
             close(newfd);
             if (oldfd != -1) close(oldfd);
             goto cleanup;
         }
 
-        if (server.appendfd == -1) {
+        if (server.aof_fd == -1) {
             /* AOF disabled, we don't need to set the AOF file descriptor
              * to this new file, so we can close it. */
             close(newfd);
         } else {
             /* AOF enabled, replace the old fd with the new one. */
-            oldfd = server.appendfd;
-            server.appendfd = newfd;
-            if (server.appendfsync == APPENDFSYNC_ALWAYS)
+            oldfd = server.aof_fd;
+            server.aof_fd = newfd;
+            if (server.aof_fsync == AOF_FSYNC_ALWAYS)
                 aof_fsync(newfd);
-            else if (server.appendfsync == APPENDFSYNC_EVERYSEC)
+            else if (server.aof_fsync == AOF_FSYNC_EVERYSEC)
                 aof_background_fsync(newfd);
-            server.appendseldb = -1; /* Make sure SELECT is re-issued */
+            server.aof_selected_db = -1; /* Make sure SELECT is re-issued */
             aofUpdateCurrentSize();
-            server.auto_aofrewrite_base_size = server.appendonly_current_size;
+            server.aof_rewrite_base_size = server.aof_current_size;
 
             /* Clear regular AOF buffer since its contents was just written to
              * the new AOF from the background rewrite buffer. */
-            sdsfree(server.aofbuf);
-            server.aofbuf = sdsempty();
+            sdsfree(server.aof_buf);
+            server.aof_buf = sdsempty();
         }
 
-        redisLog(REDIS_NOTICE, "Background AOF rewrite successful");
+        redisLog(REDIS_NOTICE, "Background AOF rewrite finished successfully");
+        /* Change state from WAIT_REWRITE to ON if needed */
+        if (server.aof_state == REDIS_AOF_WAIT_REWRITE)
+            server.aof_state = REDIS_AOF_ON;
 
         /* Asynchronously close the overwritten AOF. */
         if (oldfd != -1) bioCreateBackgroundJob(REDIS_BIO_CLOSE_FILE,(void*)(long)oldfd,NULL,NULL);
@@ -878,8 +993,11 @@ void backgroundRewriteDoneHandler(int exitcode, int bysignal) {
     }
 
 cleanup:
-    sdsfree(server.bgrewritebuf);
-    server.bgrewritebuf = sdsempty();
-    aofRemoveTempFile(server.bgrewritechildpid);
-    server.bgrewritechildpid = -1;
+    sdsfree(server.aof_rewrite_buf);
+    server.aof_rewrite_buf = sdsempty();
+    aofRemoveTempFile(server.aof_child_pid);
+    server.aof_child_pid = -1;
+    /* Schedule a new rewrite if we are waiting for it to switch the AOF ON. */
+    if (server.aof_state == REDIS_AOF_WAIT_REWRITE)
+        server.aof_rewrite_scheduled = 1;
 }