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diff --git a/src/aof.c b/src/aof.c
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+++ b/src/aof.c
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+/*
+ * Copyright (c) 2009-2012, Salvatore Sanfilippo <antirez at gmail dot com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * * Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * * Neither the name of Redis nor the names of its contributors may be used
+ * to endorse or promote products derived from this software without
+ * specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "server.h"
+#include "bio.h"
+#include "rio.h"
+#include "functions.h"
+
+#include <signal.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/time.h>
+#include <sys/resource.h>
+#include <sys/wait.h>
+#include <sys/param.h>
+
+void freeClientArgv(client *c);
+off_t getAppendOnlyFileSize(sds filename, int *status);
+off_t getBaseAndIncrAppendOnlyFilesSize(aofManifest *am, int *status);
+int getBaseAndIncrAppendOnlyFilesNum(aofManifest *am);
+int aofFileExist(char *filename);
+int rewriteAppendOnlyFile(char *filename);
+aofManifest *aofLoadManifestFromFile(sds am_filepath);
+void aofManifestFreeAndUpdate(aofManifest *am);
+void aof_background_fsync_and_close(int fd);
+
+/* ----------------------------------------------------------------------------
+ * AOF Manifest file implementation.
+ *
+ * The following code implements the read/write logic of AOF manifest file, which
+ * is used to track and manage all AOF files.
+ *
+ * Append-only files consist of three types:
+ *
+ * BASE: Represents a Redis snapshot from the time of last AOF rewrite. The manifest
+ * file contains at most a single BASE file, which will always be the first file in the
+ * list.
+ *
+ * INCR: Represents all write commands executed by Redis following the last successful
+ * AOF rewrite. In some cases it is possible to have several ordered INCR files. For
+ * example:
+ * - During an on-going AOF rewrite
+ * - After an AOF rewrite was aborted/failed, and before the next one succeeded.
+ *
+ * HISTORY: After a successful rewrite, the previous BASE and INCR become HISTORY files.
+ * They will be automatically removed unless garbage collection is disabled.
+ *
+ * The following is a possible AOF manifest file content:
+ *
+ * file appendonly.aof.2.base.rdb seq 2 type b
+ * file appendonly.aof.1.incr.aof seq 1 type h
+ * file appendonly.aof.2.incr.aof seq 2 type h
+ * file appendonly.aof.3.incr.aof seq 3 type h
+ * file appendonly.aof.4.incr.aof seq 4 type i
+ * file appendonly.aof.5.incr.aof seq 5 type i
+ * ------------------------------------------------------------------------- */
+
+/* Naming rules. */
+#define BASE_FILE_SUFFIX ".base"
+#define INCR_FILE_SUFFIX ".incr"
+#define RDB_FORMAT_SUFFIX ".rdb"
+#define AOF_FORMAT_SUFFIX ".aof"
+#define MANIFEST_NAME_SUFFIX ".manifest"
+#define TEMP_FILE_NAME_PREFIX "temp-"
+
+/* AOF manifest key. */
+#define AOF_MANIFEST_KEY_FILE_NAME "file"
+#define AOF_MANIFEST_KEY_FILE_SEQ "seq"
+#define AOF_MANIFEST_KEY_FILE_TYPE "type"
+
+/* Create an empty aofInfo. */
+aofInfo *aofInfoCreate(void) {
+ return zcalloc(sizeof(aofInfo));
+}
+
+/* Free the aofInfo structure (pointed to by ai) and its embedded file_name. */
+void aofInfoFree(aofInfo *ai) {
+ serverAssert(ai != NULL);
+ if (ai->file_name) sdsfree(ai->file_name);
+ zfree(ai);
+}
+
+/* Deep copy an aofInfo. */
+aofInfo *aofInfoDup(aofInfo *orig) {
+ serverAssert(orig != NULL);
+ aofInfo *ai = aofInfoCreate();
+ ai->file_name = sdsdup(orig->file_name);
+ ai->file_seq = orig->file_seq;
+ ai->file_type = orig->file_type;
+ return ai;
+}
+
+/* Format aofInfo as a string and it will be a line in the manifest. */
+sds aofInfoFormat(sds buf, aofInfo *ai) {
+ sds filename_repr = NULL;
+
+ if (sdsneedsrepr(ai->file_name))
+ filename_repr = sdscatrepr(sdsempty(), ai->file_name, sdslen(ai->file_name));
+
+ sds ret = sdscatprintf(buf, "%s %s %s %lld %s %c\n",
+ AOF_MANIFEST_KEY_FILE_NAME, filename_repr ? filename_repr : ai->file_name,
+ AOF_MANIFEST_KEY_FILE_SEQ, ai->file_seq,
+ AOF_MANIFEST_KEY_FILE_TYPE, ai->file_type);
+ sdsfree(filename_repr);
+
+ return ret;
+}
+
+/* Method to free AOF list elements. */
+void aofListFree(void *item) {
+ aofInfo *ai = (aofInfo *)item;
+ aofInfoFree(ai);
+}
+
+/* Method to duplicate AOF list elements. */
+void *aofListDup(void *item) {
+ return aofInfoDup(item);
+}
+
+/* Create an empty aofManifest, which will be called in `aofLoadManifestFromDisk`. */
+aofManifest *aofManifestCreate(void) {
+ aofManifest *am = zcalloc(sizeof(aofManifest));
+ am->incr_aof_list = listCreate();
+ am->history_aof_list = listCreate();
+ listSetFreeMethod(am->incr_aof_list, aofListFree);
+ listSetDupMethod(am->incr_aof_list, aofListDup);
+ listSetFreeMethod(am->history_aof_list, aofListFree);
+ listSetDupMethod(am->history_aof_list, aofListDup);
+ return am;
+}
+
+/* Free the aofManifest structure (pointed to by am) and its embedded members. */
+void aofManifestFree(aofManifest *am) {
+ if (am->base_aof_info) aofInfoFree(am->base_aof_info);
+ if (am->incr_aof_list) listRelease(am->incr_aof_list);
+ if (am->history_aof_list) listRelease(am->history_aof_list);
+ zfree(am);
+}
+
+sds getAofManifestFileName(void) {
+ return sdscatprintf(sdsempty(), "%s%s", server.aof_filename,
+ MANIFEST_NAME_SUFFIX);
+}
+
+sds getTempAofManifestFileName(void) {
+ return sdscatprintf(sdsempty(), "%s%s%s", TEMP_FILE_NAME_PREFIX,
+ server.aof_filename, MANIFEST_NAME_SUFFIX);
+}
+
+/* Returns the string representation of aofManifest pointed to by am.
+ *
+ * The string is multiple lines separated by '\n', and each line represents
+ * an AOF file.
+ *
+ * Each line is space delimited and contains 6 fields, as follows:
+ * "file" [filename] "seq" [sequence] "type" [type]
+ *
+ * Where "file", "seq" and "type" are keywords that describe the next value,
+ * [filename] and [sequence] describe file name and order, and [type] is one
+ * of 'b' (base), 'h' (history) or 'i' (incr).
+ *
+ * The base file, if exists, will always be first, followed by history files,
+ * and incremental files.
+ */
+sds getAofManifestAsString(aofManifest *am) {
+ serverAssert(am != NULL);
+
+ sds buf = sdsempty();
+ listNode *ln;
+ listIter li;
+
+ /* 1. Add BASE File information, it is always at the beginning
+ * of the manifest file. */
+ if (am->base_aof_info) {
+ buf = aofInfoFormat(buf, am->base_aof_info);
+ }
+
+ /* 2. Add HISTORY type AOF information. */
+ listRewind(am->history_aof_list, &li);
+ while ((ln = listNext(&li)) != NULL) {
+ aofInfo *ai = (aofInfo*)ln->value;
+ buf = aofInfoFormat(buf, ai);
+ }
+
+ /* 3. Add INCR type AOF information. */
+ listRewind(am->incr_aof_list, &li);
+ while ((ln = listNext(&li)) != NULL) {
+ aofInfo *ai = (aofInfo*)ln->value;
+ buf = aofInfoFormat(buf, ai);
+ }
+
+ return buf;
+}
+
+/* Load the manifest information from the disk to `server.aof_manifest`
+ * when the Redis server start.
+ *
+ * During loading, this function does strict error checking and will abort
+ * the entire Redis server process on error (I/O error, invalid format, etc.)
+ *
+ * If the AOF directory or manifest file do not exist, this will be ignored
+ * in order to support seamless upgrades from previous versions which did not
+ * use them.
+ */
+void aofLoadManifestFromDisk(void) {
+ server.aof_manifest = aofManifestCreate();
+ if (!dirExists(server.aof_dirname)) {
+ serverLog(LL_DEBUG, "The AOF directory %s doesn't exist", server.aof_dirname);
+ return;
+ }
+
+ sds am_name = getAofManifestFileName();
+ sds am_filepath = makePath(server.aof_dirname, am_name);
+ if (!fileExist(am_filepath)) {
+ serverLog(LL_DEBUG, "The AOF manifest file %s doesn't exist", am_name);
+ sdsfree(am_name);
+ sdsfree(am_filepath);
+ return;
+ }
+
+ aofManifest *am = aofLoadManifestFromFile(am_filepath);
+ if (am) aofManifestFreeAndUpdate(am);
+ sdsfree(am_name);
+ sdsfree(am_filepath);
+}
+
+/* Generic manifest loading function, used in `aofLoadManifestFromDisk` and redis-check-aof tool. */
+#define MANIFEST_MAX_LINE 1024
+aofManifest *aofLoadManifestFromFile(sds am_filepath) {
+ const char *err = NULL;
+ long long maxseq = 0;
+
+ aofManifest *am = aofManifestCreate();
+ FILE *fp = fopen(am_filepath, "r");
+ if (fp == NULL) {
+ serverLog(LL_WARNING, "Fatal error: can't open the AOF manifest "
+ "file %s for reading: %s", am_filepath, strerror(errno));
+ exit(1);
+ }
+
+ char buf[MANIFEST_MAX_LINE+1];
+ sds *argv = NULL;
+ int argc;
+ aofInfo *ai = NULL;
+
+ sds line = NULL;
+ int linenum = 0;
+
+ while (1) {
+ if (fgets(buf, MANIFEST_MAX_LINE+1, fp) == NULL) {
+ if (feof(fp)) {
+ if (linenum == 0) {
+ err = "Found an empty AOF manifest";
+ goto loaderr;
+ } else {
+ break;
+ }
+ } else {
+ err = "Read AOF manifest failed";
+ goto loaderr;
+ }
+ }
+
+ linenum++;
+
+ /* Skip comments lines */
+ if (buf[0] == '#') continue;
+
+ if (strchr(buf, '\n') == NULL) {
+ err = "The AOF manifest file contains too long line";
+ goto loaderr;
+ }
+
+ line = sdstrim(sdsnew(buf), " \t\r\n");
+ if (!sdslen(line)) {
+ err = "Invalid AOF manifest file format";
+ goto loaderr;
+ }
+
+ argv = sdssplitargs(line, &argc);
+ /* 'argc < 6' was done for forward compatibility. */
+ if (argv == NULL || argc < 6 || (argc % 2)) {
+ err = "Invalid AOF manifest file format";
+ goto loaderr;
+ }
+
+ ai = aofInfoCreate();
+ for (int i = 0; i < argc; i += 2) {
+ if (!strcasecmp(argv[i], AOF_MANIFEST_KEY_FILE_NAME)) {
+ ai->file_name = sdsnew(argv[i+1]);
+ if (!pathIsBaseName(ai->file_name)) {
+ err = "File can't be a path, just a filename";
+ goto loaderr;
+ }
+ } else if (!strcasecmp(argv[i], AOF_MANIFEST_KEY_FILE_SEQ)) {
+ ai->file_seq = atoll(argv[i+1]);
+ } else if (!strcasecmp(argv[i], AOF_MANIFEST_KEY_FILE_TYPE)) {
+ ai->file_type = (argv[i+1])[0];
+ }
+ /* else if (!strcasecmp(argv[i], AOF_MANIFEST_KEY_OTHER)) {} */
+ }
+
+ /* We have to make sure we load all the information. */
+ if (!ai->file_name || !ai->file_seq || !ai->file_type) {
+ err = "Invalid AOF manifest file format";
+ goto loaderr;
+ }
+
+ sdsfreesplitres(argv, argc);
+ argv = NULL;
+
+ if (ai->file_type == AOF_FILE_TYPE_BASE) {
+ if (am->base_aof_info) {
+ err = "Found duplicate base file information";
+ goto loaderr;
+ }
+ am->base_aof_info = ai;
+ am->curr_base_file_seq = ai->file_seq;
+ } else if (ai->file_type == AOF_FILE_TYPE_HIST) {
+ listAddNodeTail(am->history_aof_list, ai);
+ } else if (ai->file_type == AOF_FILE_TYPE_INCR) {
+ if (ai->file_seq <= maxseq) {
+ err = "Found a non-monotonic sequence number";
+ goto loaderr;
+ }
+ listAddNodeTail(am->incr_aof_list, ai);
+ am->curr_incr_file_seq = ai->file_seq;
+ maxseq = ai->file_seq;
+ } else {
+ err = "Unknown AOF file type";
+ goto loaderr;
+ }
+
+ sdsfree(line);
+ line = NULL;
+ ai = NULL;
+ }
+
+ fclose(fp);
+ return am;
+
+loaderr:
+ /* Sanitizer suppression: may report a false positive if we goto loaderr
+ * and exit(1) without freeing these allocations. */
+ if (argv) sdsfreesplitres(argv, argc);
+ if (ai) aofInfoFree(ai);
+
+ serverLog(LL_WARNING, "\n*** FATAL AOF MANIFEST FILE ERROR ***\n");
+ if (line) {
+ serverLog(LL_WARNING, "Reading the manifest file, at line %d\n", linenum);
+ serverLog(LL_WARNING, ">>> '%s'\n", line);
+ }
+ serverLog(LL_WARNING, "%s\n", err);
+ exit(1);
+}
+
+/* Deep copy an aofManifest from orig.
+ *
+ * In `backgroundRewriteDoneHandler` and `openNewIncrAofForAppend`, we will
+ * first deep copy a temporary AOF manifest from the `server.aof_manifest` and
+ * try to modify it. Once everything is modified, we will atomically make the
+ * `server.aof_manifest` point to this temporary aof_manifest.
+ */
+aofManifest *aofManifestDup(aofManifest *orig) {
+ serverAssert(orig != NULL);
+ aofManifest *am = zcalloc(sizeof(aofManifest));
+
+ am->curr_base_file_seq = orig->curr_base_file_seq;
+ am->curr_incr_file_seq = orig->curr_incr_file_seq;
+ am->dirty = orig->dirty;
+
+ if (orig->base_aof_info) {
+ am->base_aof_info = aofInfoDup(orig->base_aof_info);
+ }
+
+ am->incr_aof_list = listDup(orig->incr_aof_list);
+ am->history_aof_list = listDup(orig->history_aof_list);
+ serverAssert(am->incr_aof_list != NULL);
+ serverAssert(am->history_aof_list != NULL);
+ return am;
+}
+
+/* Change the `server.aof_manifest` pointer to 'am' and free the previous
+ * one if we have. */
+void aofManifestFreeAndUpdate(aofManifest *am) {
+ serverAssert(am != NULL);
+ if (server.aof_manifest) aofManifestFree(server.aof_manifest);
+ server.aof_manifest = am;
+}
+
+/* Called in `backgroundRewriteDoneHandler` to get a new BASE file
+ * name, and mark the previous (if we have) BASE file as HISTORY type.
+ *
+ * BASE file naming rules: `server.aof_filename`.seq.base.format
+ *
+ * for example:
+ * appendonly.aof.1.base.aof (server.aof_use_rdb_preamble is no)
+ * appendonly.aof.1.base.rdb (server.aof_use_rdb_preamble is yes)
+ */
+sds getNewBaseFileNameAndMarkPreAsHistory(aofManifest *am) {
+ serverAssert(am != NULL);
+ if (am->base_aof_info) {
+ serverAssert(am->base_aof_info->file_type == AOF_FILE_TYPE_BASE);
+ am->base_aof_info->file_type = AOF_FILE_TYPE_HIST;
+ listAddNodeHead(am->history_aof_list, am->base_aof_info);
+ }
+
+ char *format_suffix = server.aof_use_rdb_preamble ?
+ RDB_FORMAT_SUFFIX:AOF_FORMAT_SUFFIX;
+
+ aofInfo *ai = aofInfoCreate();
+ ai->file_name = sdscatprintf(sdsempty(), "%s.%lld%s%s", server.aof_filename,
+ ++am->curr_base_file_seq, BASE_FILE_SUFFIX, format_suffix);
+ ai->file_seq = am->curr_base_file_seq;
+ ai->file_type = AOF_FILE_TYPE_BASE;
+ am->base_aof_info = ai;
+ am->dirty = 1;
+ return am->base_aof_info->file_name;
+}
+
+/* Get a new INCR type AOF name.
+ *
+ * INCR AOF naming rules: `server.aof_filename`.seq.incr.aof
+ *
+ * for example:
+ * appendonly.aof.1.incr.aof
+ */
+sds getNewIncrAofName(aofManifest *am) {
+ aofInfo *ai = aofInfoCreate();
+ ai->file_type = AOF_FILE_TYPE_INCR;
+ ai->file_name = sdscatprintf(sdsempty(), "%s.%lld%s%s", server.aof_filename,
+ ++am->curr_incr_file_seq, INCR_FILE_SUFFIX, AOF_FORMAT_SUFFIX);
+ ai->file_seq = am->curr_incr_file_seq;
+ listAddNodeTail(am->incr_aof_list, ai);
+ am->dirty = 1;
+ return ai->file_name;
+}
+
+/* Get temp INCR type AOF name. */
+sds getTempIncrAofName(void) {
+ return sdscatprintf(sdsempty(), "%s%s%s", TEMP_FILE_NAME_PREFIX, server.aof_filename,
+ INCR_FILE_SUFFIX);
+}
+
+/* Get the last INCR AOF name or create a new one. */
+sds getLastIncrAofName(aofManifest *am) {
+ serverAssert(am != NULL);
+
+ /* If 'incr_aof_list' is empty, just create a new one. */
+ if (!listLength(am->incr_aof_list)) {
+ return getNewIncrAofName(am);
+ }
+
+ /* Or return the last one. */
+ listNode *lastnode = listIndex(am->incr_aof_list, -1);
+ aofInfo *ai = listNodeValue(lastnode);
+ return ai->file_name;
+}
+
+/* Called in `backgroundRewriteDoneHandler`. when AOFRW success, This
+ * function will change the AOF file type in 'incr_aof_list' from
+ * AOF_FILE_TYPE_INCR to AOF_FILE_TYPE_HIST, and move them to the
+ * 'history_aof_list'.
+ */
+void markRewrittenIncrAofAsHistory(aofManifest *am) {
+ serverAssert(am != NULL);
+ if (!listLength(am->incr_aof_list)) {
+ return;
+ }
+
+ listNode *ln;
+ listIter li;
+
+ listRewindTail(am->incr_aof_list, &li);
+
+ /* "server.aof_fd != -1" means AOF enabled, then we must skip the
+ * last AOF, because this file is our currently writing. */
+ if (server.aof_fd != -1) {
+ ln = listNext(&li);
+ serverAssert(ln != NULL);
+ }
+
+ /* Move aofInfo from 'incr_aof_list' to 'history_aof_list'. */
+ while ((ln = listNext(&li)) != NULL) {
+ aofInfo *ai = (aofInfo*)ln->value;
+ serverAssert(ai->file_type == AOF_FILE_TYPE_INCR);
+
+ aofInfo *hai = aofInfoDup(ai);
+ hai->file_type = AOF_FILE_TYPE_HIST;
+ listAddNodeHead(am->history_aof_list, hai);
+ listDelNode(am->incr_aof_list, ln);
+ }
+
+ am->dirty = 1;
+}
+
+/* Write the formatted manifest string to disk. */
+int writeAofManifestFile(sds buf) {
+ int ret = C_OK;
+ ssize_t nwritten;
+ int len;
+
+ sds am_name = getAofManifestFileName();
+ sds am_filepath = makePath(server.aof_dirname, am_name);
+ sds tmp_am_name = getTempAofManifestFileName();
+ sds tmp_am_filepath = makePath(server.aof_dirname, tmp_am_name);
+
+ int fd = open(tmp_am_filepath, O_WRONLY|O_TRUNC|O_CREAT, 0644);
+ if (fd == -1) {
+ serverLog(LL_WARNING, "Can't open the AOF manifest file %s: %s",
+ tmp_am_name, strerror(errno));
+
+ ret = C_ERR;
+ goto cleanup;
+ }
+
+ len = sdslen(buf);
+ while(len) {
+ nwritten = write(fd, buf, len);
+
+ if (nwritten < 0) {
+ if (errno == EINTR) continue;
+
+ serverLog(LL_WARNING, "Error trying to write the temporary AOF manifest file %s: %s",
+ tmp_am_name, strerror(errno));
+
+ ret = C_ERR;
+ goto cleanup;
+ }
+
+ len -= nwritten;
+ buf += nwritten;
+ }
+
+ if (redis_fsync(fd) == -1) {
+ serverLog(LL_WARNING, "Fail to fsync the temp AOF file %s: %s.",
+ tmp_am_name, strerror(errno));
+
+ ret = C_ERR;
+ goto cleanup;
+ }
+
+ if (rename(tmp_am_filepath, am_filepath) != 0) {
+ serverLog(LL_WARNING,
+ "Error trying to rename the temporary AOF manifest file %s into %s: %s",
+ tmp_am_name, am_name, strerror(errno));
+
+ ret = C_ERR;
+ goto cleanup;
+ }
+
+ /* Also sync the AOF directory as new AOF files may be added in the directory */
+ if (fsyncFileDir(am_filepath) == -1) {
+ serverLog(LL_WARNING, "Fail to fsync AOF directory %s: %s.",
+ am_filepath, strerror(errno));
+
+ ret = C_ERR;
+ goto cleanup;
+ }
+
+cleanup:
+ if (fd != -1) close(fd);
+ sdsfree(am_name);
+ sdsfree(am_filepath);
+ sdsfree(tmp_am_name);
+ sdsfree(tmp_am_filepath);
+ return ret;
+}
+
+/* Persist the aofManifest information pointed to by am to disk. */
+int persistAofManifest(aofManifest *am) {
+ if (am->dirty == 0) {
+ return C_OK;
+ }
+
+ sds amstr = getAofManifestAsString(am);
+ int ret = writeAofManifestFile(amstr);
+ sdsfree(amstr);
+ if (ret == C_OK) am->dirty = 0;
+ return ret;
+}
+
+/* Called in `loadAppendOnlyFiles` when we upgrade from a old version redis.
+ *
+ * 1) Create AOF directory use 'server.aof_dirname' as the name.
+ * 2) Use 'server.aof_filename' to construct a BASE type aofInfo and add it to
+ * aofManifest, then persist the manifest file to AOF directory.
+ * 3) Move the old AOF file (server.aof_filename) to AOF directory.
+ *
+ * If any of the above steps fails or crash occurs, this will not cause any
+ * problems, and redis will retry the upgrade process when it restarts.
+ */
+void aofUpgradePrepare(aofManifest *am) {
+ serverAssert(!aofFileExist(server.aof_filename));
+
+ /* Create AOF directory use 'server.aof_dirname' as the name. */
+ if (dirCreateIfMissing(server.aof_dirname) == -1) {
+ serverLog(LL_WARNING, "Can't open or create append-only dir %s: %s",
+ server.aof_dirname, strerror(errno));
+ exit(1);
+ }
+
+ /* Manually construct a BASE type aofInfo and add it to aofManifest. */
+ if (am->base_aof_info) aofInfoFree(am->base_aof_info);
+ aofInfo *ai = aofInfoCreate();
+ ai->file_name = sdsnew(server.aof_filename);
+ ai->file_seq = 1;
+ ai->file_type = AOF_FILE_TYPE_BASE;
+ am->base_aof_info = ai;
+ am->curr_base_file_seq = 1;
+ am->dirty = 1;
+
+ /* Persist the manifest file to AOF directory. */
+ if (persistAofManifest(am) != C_OK) {
+ exit(1);
+ }
+
+ /* Move the old AOF file to AOF directory. */
+ sds aof_filepath = makePath(server.aof_dirname, server.aof_filename);
+ if (rename(server.aof_filename, aof_filepath) == -1) {
+ serverLog(LL_WARNING,
+ "Error trying to move the old AOF file %s into dir %s: %s",
+ server.aof_filename,
+ server.aof_dirname,
+ strerror(errno));
+ sdsfree(aof_filepath);
+ exit(1);
+ }
+ sdsfree(aof_filepath);
+
+ serverLog(LL_NOTICE, "Successfully migrated an old-style AOF file (%s) into the AOF directory (%s).",
+ server.aof_filename, server.aof_dirname);
+}
+
+/* When AOFRW success, the previous BASE and INCR AOFs will
+ * become HISTORY type and be moved into 'history_aof_list'.
+ *
+ * The function will traverse the 'history_aof_list' and submit
+ * the delete task to the bio thread.
+ */
+int aofDelHistoryFiles(void) {
+ if (server.aof_manifest == NULL ||
+ server.aof_disable_auto_gc == 1 ||
+ !listLength(server.aof_manifest->history_aof_list))
+ {
+ return C_OK;
+ }
+
+ listNode *ln;
+ listIter li;
+
+ listRewind(server.aof_manifest->history_aof_list, &li);
+ while ((ln = listNext(&li)) != NULL) {
+ aofInfo *ai = (aofInfo*)ln->value;
+ serverAssert(ai->file_type == AOF_FILE_TYPE_HIST);
+ serverLog(LL_NOTICE, "Removing the history file %s in the background", ai->file_name);
+ sds aof_filepath = makePath(server.aof_dirname, ai->file_name);
+ bg_unlink(aof_filepath);
+ sdsfree(aof_filepath);
+ listDelNode(server.aof_manifest->history_aof_list, ln);
+ }
+
+ server.aof_manifest->dirty = 1;
+ return persistAofManifest(server.aof_manifest);
+}
+
+/* Used to clean up temp INCR AOF when AOFRW fails. */
+void aofDelTempIncrAofFile(void) {
+ sds aof_filename = getTempIncrAofName();
+ sds aof_filepath = makePath(server.aof_dirname, aof_filename);
+ serverLog(LL_NOTICE, "Removing the temp incr aof file %s in the background", aof_filename);
+ bg_unlink(aof_filepath);
+ sdsfree(aof_filepath);
+ sdsfree(aof_filename);
+ return;
+}
+
+/* Called after `loadDataFromDisk` when redis start. If `server.aof_state` is
+ * 'AOF_ON', It will do three things:
+ * 1. Force create a BASE file when redis starts with an empty dataset
+ * 2. Open the last opened INCR type AOF for writing, If not, create a new one
+ * 3. Synchronously update the manifest file to the disk
+ *
+ * If any of the above steps fails, the redis process will exit.
+ */
+void aofOpenIfNeededOnServerStart(void) {
+ if (server.aof_state != AOF_ON) {
+ return;
+ }
+
+ serverAssert(server.aof_manifest != NULL);
+ serverAssert(server.aof_fd == -1);
+
+ if (dirCreateIfMissing(server.aof_dirname) == -1) {
+ serverLog(LL_WARNING, "Can't open or create append-only dir %s: %s",
+ server.aof_dirname, strerror(errno));
+ exit(1);
+ }
+
+ /* If we start with an empty dataset, we will force create a BASE file. */
+ size_t incr_aof_len = listLength(server.aof_manifest->incr_aof_list);
+ if (!server.aof_manifest->base_aof_info && !incr_aof_len) {
+ sds base_name = getNewBaseFileNameAndMarkPreAsHistory(server.aof_manifest);
+ sds base_filepath = makePath(server.aof_dirname, base_name);
+ if (rewriteAppendOnlyFile(base_filepath) != C_OK) {
+ exit(1);
+ }
+ sdsfree(base_filepath);
+ serverLog(LL_NOTICE, "Creating AOF base file %s on server start",
+ base_name);
+ }
+
+ /* Because we will 'exit(1)' if open AOF or persistent manifest fails, so
+ * we don't need atomic modification here. */
+ sds aof_name = getLastIncrAofName(server.aof_manifest);
+
+ /* Here we should use 'O_APPEND' flag. */
+ sds aof_filepath = makePath(server.aof_dirname, aof_name);
+ server.aof_fd = open(aof_filepath, O_WRONLY|O_APPEND|O_CREAT, 0644);
+ sdsfree(aof_filepath);
+ if (server.aof_fd == -1) {
+ serverLog(LL_WARNING, "Can't open the append-only file %s: %s",
+ aof_name, strerror(errno));
+ exit(1);
+ }
+
+ /* Persist our changes. */
+ int ret = persistAofManifest(server.aof_manifest);
+ if (ret != C_OK) {
+ exit(1);
+ }
+
+ server.aof_last_incr_size = getAppendOnlyFileSize(aof_name, NULL);
+ server.aof_last_incr_fsync_offset = server.aof_last_incr_size;
+
+ if (incr_aof_len) {
+ serverLog(LL_NOTICE, "Opening AOF incr file %s on server start", aof_name);
+ } else {
+ serverLog(LL_NOTICE, "Creating AOF incr file %s on server start", aof_name);
+ }
+}
+
+int aofFileExist(char *filename) {
+ sds file_path = makePath(server.aof_dirname, filename);
+ int ret = fileExist(file_path);
+ sdsfree(file_path);
+ return ret;
+}
+
+/* Called in `rewriteAppendOnlyFileBackground`. If `server.aof_state`
+ * is 'AOF_ON', It will do two things:
+ * 1. Open a new INCR type AOF for writing
+ * 2. Synchronously update the manifest file to the disk
+ *
+ * The above two steps of modification are atomic, that is, if
+ * any step fails, the entire operation will rollback and returns
+ * C_ERR, and if all succeeds, it returns C_OK.
+ *
+ * If `server.aof_state` is 'AOF_WAIT_REWRITE', It will open a temporary INCR AOF
+ * file to accumulate data during AOF_WAIT_REWRITE, and it will eventually be
+ * renamed in the `backgroundRewriteDoneHandler` and written to the manifest file.
+ * */
+int openNewIncrAofForAppend(void) {
+ serverAssert(server.aof_manifest != NULL);
+ int newfd = -1;
+ aofManifest *temp_am = NULL;
+ sds new_aof_name = NULL;
+
+ /* Only open new INCR AOF when AOF enabled. */
+ if (server.aof_state == AOF_OFF) return C_OK;
+
+ /* Open new AOF. */
+ if (server.aof_state == AOF_WAIT_REWRITE) {
+ /* Use a temporary INCR AOF file to accumulate data during AOF_WAIT_REWRITE. */
+ new_aof_name = getTempIncrAofName();
+ } else {
+ /* Dup a temp aof_manifest to modify. */
+ temp_am = aofManifestDup(server.aof_manifest);
+ new_aof_name = sdsdup(getNewIncrAofName(temp_am));
+ }
+ sds new_aof_filepath = makePath(server.aof_dirname, new_aof_name);
+ newfd = open(new_aof_filepath, O_WRONLY|O_TRUNC|O_CREAT, 0644);
+ sdsfree(new_aof_filepath);
+ if (newfd == -1) {
+ serverLog(LL_WARNING, "Can't open the append-only file %s: %s",
+ new_aof_name, strerror(errno));
+ goto cleanup;
+ }
+
+ if (temp_am) {
+ /* Persist AOF Manifest. */
+ if (persistAofManifest(temp_am) == C_ERR) {
+ goto cleanup;
+ }
+ }
+
+ serverLog(LL_NOTICE, "Creating AOF incr file %s on background rewrite",
+ new_aof_name);
+ sdsfree(new_aof_name);
+
+ /* If reaches here, we can safely modify the `server.aof_manifest`
+ * and `server.aof_fd`. */
+
+ /* fsync and close old aof_fd if needed. In fsync everysec it's ok to delay
+ * the fsync as long as we grantee it happens, and in fsync always the file
+ * is already synced at this point so fsync doesn't matter. */
+ if (server.aof_fd != -1) {
+ aof_background_fsync_and_close(server.aof_fd);
+ server.aof_last_fsync = server.unixtime;
+ }
+ server.aof_fd = newfd;
+
+ /* Reset the aof_last_incr_size. */
+ server.aof_last_incr_size = 0;
+ /* Reset the aof_last_incr_fsync_offset. */
+ server.aof_last_incr_fsync_offset = 0;
+ /* Update `server.aof_manifest`. */
+ if (temp_am) aofManifestFreeAndUpdate(temp_am);
+ return C_OK;
+
+cleanup:
+ if (new_aof_name) sdsfree(new_aof_name);
+ if (newfd != -1) close(newfd);
+ if (temp_am) aofManifestFree(temp_am);
+ return C_ERR;
+}
+
+/* Whether to limit the execution of Background AOF rewrite.
+ *
+ * At present, if AOFRW fails, redis will automatically retry. If it continues
+ * to fail, we may get a lot of very small INCR files. so we need an AOFRW
+ * limiting measure.
+ *
+ * We can't directly use `server.aof_current_size` and `server.aof_last_incr_size`,
+ * because there may be no new writes after AOFRW fails.
+ *
+ * So, we use time delay to achieve our goal. When AOFRW fails, we delay the execution
+ * of the next AOFRW by 1 minute. If the next AOFRW also fails, it will be delayed by 2
+ * minutes. The next is 4, 8, 16, the maximum delay is 60 minutes (1 hour).
+ *
+ * During the limit period, we can still use the 'bgrewriteaof' command to execute AOFRW
+ * immediately.
+ *
+ * Return 1 means that AOFRW is limited and cannot be executed. 0 means that we can execute
+ * AOFRW, which may be that we have reached the 'next_rewrite_time' or the number of INCR
+ * AOFs has not reached the limit threshold.
+ * */
+#define AOF_REWRITE_LIMITE_THRESHOLD 3
+#define AOF_REWRITE_LIMITE_MAX_MINUTES 60 /* 1 hour */
+int aofRewriteLimited(void) {
+ static int next_delay_minutes = 0;
+ static time_t next_rewrite_time = 0;
+
+ if (server.stat_aofrw_consecutive_failures < AOF_REWRITE_LIMITE_THRESHOLD) {
+ /* We may be recovering from limited state, so reset all states. */
+ next_delay_minutes = 0;
+ next_rewrite_time = 0;
+ return 0;
+ }
+
+ /* if it is in the limiting state, then check if the next_rewrite_time is reached */
+ if (next_rewrite_time != 0) {
+ if (server.unixtime < next_rewrite_time) {
+ return 1;
+ } else {
+ next_rewrite_time = 0;
+ return 0;
+ }
+ }
+
+ next_delay_minutes = (next_delay_minutes == 0) ? 1 : (next_delay_minutes * 2);
+ if (next_delay_minutes > AOF_REWRITE_LIMITE_MAX_MINUTES) {
+ next_delay_minutes = AOF_REWRITE_LIMITE_MAX_MINUTES;
+ }
+
+ next_rewrite_time = server.unixtime + next_delay_minutes * 60;
+ serverLog(LL_WARNING,
+ "Background AOF rewrite has repeatedly failed and triggered the limit, will retry in %d minutes", next_delay_minutes);
+ return 1;
+}
+
+/* ----------------------------------------------------------------------------
+ * AOF file implementation
+ * ------------------------------------------------------------------------- */
+
+/* Return true if an AOf fsync is currently already in progress in a
+ * BIO thread. */
+int aofFsyncInProgress(void) {
+ /* Note that we don't care about aof_background_fsync_and_close because
+ * server.aof_fd has been replaced by the new INCR AOF file fd,
+ * see openNewIncrAofForAppend. */
+ return bioPendingJobsOfType(BIO_AOF_FSYNC) != 0;
+}
+
+/* Starts a background task that performs fsync() against the specified
+ * file descriptor (the one of the AOF file) in another thread. */
+void aof_background_fsync(int fd) {
+ bioCreateFsyncJob(fd, server.master_repl_offset, 1);
+}
+
+/* Close the fd on the basis of aof_background_fsync. */
+void aof_background_fsync_and_close(int fd) {
+ bioCreateCloseAofJob(fd, server.master_repl_offset, 1);
+}
+
+/* Kills an AOFRW child process if exists */
+void killAppendOnlyChild(void) {
+ int statloc;
+ /* No AOFRW child? return. */
+ if (server.child_type != CHILD_TYPE_AOF) return;
+ /* Kill AOFRW child, wait for child exit. */
+ serverLog(LL_NOTICE,"Killing running AOF rewrite child: %ld",
+ (long) server.child_pid);
+ if (kill(server.child_pid,SIGUSR1) != -1) {
+ while(waitpid(-1, &statloc, 0) != server.child_pid);
+ }
+ aofRemoveTempFile(server.child_pid);
+ resetChildState();
+ server.aof_rewrite_time_start = -1;
+}
+
+/* Called when the user switches from "appendonly yes" to "appendonly no"
+ * at runtime using the CONFIG command. */
+void stopAppendOnly(void) {
+ serverAssert(server.aof_state != AOF_OFF);
+ flushAppendOnlyFile(1);
+ if (redis_fsync(server.aof_fd) == -1) {
+ serverLog(LL_WARNING,"Fail to fsync the AOF file: %s",strerror(errno));
+ } else {
+ server.aof_last_fsync = server.unixtime;
+ }
+ close(server.aof_fd);
+
+ server.aof_fd = -1;
+ server.aof_selected_db = -1;
+ server.aof_state = AOF_OFF;
+ server.aof_rewrite_scheduled = 0;
+ server.aof_last_incr_size = 0;
+ server.aof_last_incr_fsync_offset = 0;
+ server.fsynced_reploff = -1;
+ atomicSet(server.fsynced_reploff_pending, 0);
+ killAppendOnlyChild();
+ sdsfree(server.aof_buf);
+ server.aof_buf = sdsempty();
+}
+
+/* Called when the user switches from "appendonly no" to "appendonly yes"
+ * at runtime using the CONFIG command. */
+int startAppendOnly(void) {
+ serverAssert(server.aof_state == AOF_OFF);
+
+ server.aof_state = AOF_WAIT_REWRITE;
+ if (hasActiveChildProcess() && server.child_type != CHILD_TYPE_AOF) {
+ server.aof_rewrite_scheduled = 1;
+ serverLog(LL_NOTICE,"AOF was enabled but there is already another background operation. An AOF background was scheduled to start when possible.");
+ } else if (server.in_exec){
+ server.aof_rewrite_scheduled = 1;
+ serverLog(LL_NOTICE,"AOF was enabled during a transaction. An AOF background was scheduled to start when possible.");
+ } else {
+ /* If there is a pending AOF rewrite, we need to switch it off and
+ * start a new one: the old one cannot be reused because it is not
+ * accumulating the AOF buffer. */
+ if (server.child_type == CHILD_TYPE_AOF) {
+ serverLog(LL_NOTICE,"AOF was enabled but there is already an AOF rewriting in background. Stopping background AOF and starting a rewrite now.");
+ killAppendOnlyChild();
+ }
+
+ if (rewriteAppendOnlyFileBackground() == C_ERR) {
+ server.aof_state = AOF_OFF;
+ serverLog(LL_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 C_ERR;
+ }
+ }
+ server.aof_last_fsync = server.unixtime;
+ /* If AOF fsync error in bio job, we just ignore it and log the event. */
+ int aof_bio_fsync_status;
+ atomicGet(server.aof_bio_fsync_status, aof_bio_fsync_status);
+ if (aof_bio_fsync_status == C_ERR) {
+ serverLog(LL_WARNING,
+ "AOF reopen, just ignore the AOF fsync error in bio job");
+ atomicSet(server.aof_bio_fsync_status,C_OK);
+ }
+
+ /* If AOF was in error state, we just ignore it and log the event. */
+ if (server.aof_last_write_status == C_ERR) {
+ serverLog(LL_WARNING,"AOF reopen, just ignore the last error.");
+ server.aof_last_write_status = C_OK;
+ }
+ return C_OK;
+}
+
+/* This is a wrapper to the write syscall in order to retry on short writes
+ * or if the syscall gets interrupted. It could look strange that we retry
+ * on short writes given that we are writing to a block device: normally if
+ * the first call is short, there is a end-of-space condition, so the next
+ * is likely to fail. However apparently in modern systems this is no longer
+ * true, and in general it looks just more resilient to retry the write. If
+ * there is an actual error condition we'll get it at the next try. */
+ssize_t aofWrite(int fd, const char *buf, size_t len) {
+ ssize_t nwritten = 0, totwritten = 0;
+
+ while(len) {
+ nwritten = write(fd, buf, len);
+
+ if (nwritten < 0) {
+ if (errno == EINTR) continue;
+ return totwritten ? totwritten : -1;
+ }
+
+ len -= nwritten;
+ buf += nwritten;
+ totwritten += nwritten;
+ }
+
+ return totwritten;
+}
+
+/* Write the append only file buffer on disk.
+ *
+ * Since we are required to write the AOF before replying to the client,
+ * and the only way the client socket can get a write is entering when
+ * the event loop, we accumulate all the AOF writes in a memory
+ * buffer and write it on disk using this function just before entering
+ * the event loop again.
+ *
+ * About the 'force' argument:
+ *
+ * When the fsync policy is set to 'everysec' we may delay the flush if there
+ * is still an fsync() going on in the background thread, since for instance
+ * on Linux write(2) will be blocked by the background fsync anyway.
+ * When this happens we remember that there is some aof buffer to be
+ * flushed ASAP, and will try to do that in the serverCron() function.
+ *
+ * However if force is set to 1 we'll write regardless of the background
+ * fsync. */
+#define AOF_WRITE_LOG_ERROR_RATE 30 /* Seconds between errors logging. */
+void flushAppendOnlyFile(int force) {
+ ssize_t nwritten;
+ int sync_in_progress = 0;
+ mstime_t latency;
+
+ if (sdslen(server.aof_buf) == 0) {
+ /* Check if we need to do fsync even the aof buffer is empty,
+ * because previously in AOF_FSYNC_EVERYSEC mode, fsync is
+ * called only when aof buffer is not empty, so if users
+ * stop write commands before fsync called in one second,
+ * the data in page cache cannot be flushed in time. */
+ if (server.aof_fsync == AOF_FSYNC_EVERYSEC &&
+ server.aof_last_incr_fsync_offset != server.aof_last_incr_size &&
+ server.unixtime > server.aof_last_fsync &&
+ !(sync_in_progress = aofFsyncInProgress())) {
+ goto try_fsync;
+
+ /* Check if we need to do fsync even the aof buffer is empty,
+ * the reason is described in the previous AOF_FSYNC_EVERYSEC block,
+ * and AOF_FSYNC_ALWAYS is also checked here to handle a case where
+ * aof_fsync is changed from everysec to always. */
+ } else if (server.aof_fsync == AOF_FSYNC_ALWAYS &&
+ server.aof_last_incr_fsync_offset != server.aof_last_incr_size)
+ {
+ goto try_fsync;
+ } else {
+ return;
+ }
+ }
+
+ if (server.aof_fsync == AOF_FSYNC_EVERYSEC)
+ sync_in_progress = aofFsyncInProgress();
+
+ 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. */
+ if (sync_in_progress) {
+ if (server.aof_flush_postponed_start == 0) {
+ /* No previous write postponing, remember that we are
+ * postponing the flush and return. */
+ server.aof_flush_postponed_start = server.unixtime;
+ return;
+ } else if (server.unixtime - server.aof_flush_postponed_start < 2) {
+ /* We were already waiting for fsync to finish, but for less
+ * than two seconds this is still ok. Postpone again. */
+ return;
+ }
+ /* Otherwise fall through, and go write since we can't wait
+ * over two seconds. */
+ server.aof_delayed_fsync++;
+ serverLog(LL_NOTICE,"Asynchronous AOF fsync is taking too long (disk is busy?). Writing the AOF buffer without waiting for fsync to complete, this may slow down Redis.");
+ }
+ }
+ /* We want to perform a single write. This should be guaranteed atomic
+ * at least if the filesystem we are writing is a real physical one.
+ * 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 */
+
+ if (server.aof_flush_sleep && sdslen(server.aof_buf)) {
+ usleep(server.aof_flush_sleep);
+ }
+
+ latencyStartMonitor(latency);
+ nwritten = aofWrite(server.aof_fd,server.aof_buf,sdslen(server.aof_buf));
+ latencyEndMonitor(latency);
+ /* We want to capture different events for delayed writes:
+ * when the delay happens with a pending fsync, or with a saving child
+ * active, and when the above two conditions are missing.
+ * We also use an additional event name to save all samples which is
+ * useful for graphing / monitoring purposes. */
+ if (sync_in_progress) {
+ latencyAddSampleIfNeeded("aof-write-pending-fsync",latency);
+ } else if (hasActiveChildProcess()) {
+ latencyAddSampleIfNeeded("aof-write-active-child",latency);
+ } else {
+ latencyAddSampleIfNeeded("aof-write-alone",latency);
+ }
+ latencyAddSampleIfNeeded("aof-write",latency);
+
+ /* We performed the write so reset the postponed flush sentinel to zero. */
+ server.aof_flush_postponed_start = 0;
+
+ if (nwritten != (ssize_t)sdslen(server.aof_buf)) {
+ static time_t last_write_error_log = 0;
+ int can_log = 0;
+
+ /* Limit logging rate to 1 line per AOF_WRITE_LOG_ERROR_RATE seconds. */
+ if ((server.unixtime - last_write_error_log) > AOF_WRITE_LOG_ERROR_RATE) {
+ can_log = 1;
+ last_write_error_log = server.unixtime;
+ }
+
+ /* Log the AOF write error and record the error code. */
+ if (nwritten == -1) {
+ if (can_log) {
+ serverLog(LL_WARNING,"Error writing to the AOF file: %s",
+ strerror(errno));
+ }
+ server.aof_last_write_errno = errno;
+ } else {
+ if (can_log) {
+ serverLog(LL_WARNING,"Short write while writing to "
+ "the AOF file: (nwritten=%lld, "
+ "expected=%lld)",
+ (long long)nwritten,
+ (long long)sdslen(server.aof_buf));
+ }
+
+ if (ftruncate(server.aof_fd, server.aof_last_incr_size) == -1) {
+ if (can_log) {
+ serverLog(LL_WARNING, "Could not remove short write "
+ "from the append-only file. Redis may refuse "
+ "to load the AOF the next time it starts. "
+ "ftruncate: %s", strerror(errno));
+ }
+ } else {
+ /* If the ftruncate() succeeded we can set nwritten to
+ * -1 since there is no longer partial data into the AOF. */
+ nwritten = -1;
+ }
+ server.aof_last_write_errno = ENOSPC;
+ }
+
+ /* Handle the AOF write error. */
+ if (server.aof_fsync == AOF_FSYNC_ALWAYS) {
+ /* We can't recover when the fsync policy is ALWAYS since the reply
+ * for the client is already in the output buffers (both writes and
+ * reads), and the changes to the db can't be rolled back. Since we
+ * have a contract with the user that on acknowledged or observed
+ * writes are is synced on disk, we must exit. */
+ serverLog(LL_WARNING,"Can't recover from AOF write error when the AOF fsync policy is 'always'. Exiting...");
+ exit(1);
+ } else {
+ /* Recover from failed write leaving data into the buffer. However
+ * set an error to stop accepting writes as long as the error
+ * condition is not cleared. */
+ server.aof_last_write_status = C_ERR;
+
+ /* Trim the sds buffer if there was a partial write, and there
+ * was no way to undo it with ftruncate(2). */
+ if (nwritten > 0) {
+ server.aof_current_size += nwritten;
+ server.aof_last_incr_size += nwritten;
+ sdsrange(server.aof_buf,nwritten,-1);
+ }
+ return; /* We'll try again on the next call... */
+ }
+ } else {
+ /* Successful write(2). If AOF was in error state, restore the
+ * OK state and log the event. */
+ if (server.aof_last_write_status == C_ERR) {
+ serverLog(LL_NOTICE,
+ "AOF write error looks solved, Redis can write again.");
+ server.aof_last_write_status = C_OK;
+ }
+ }
+ server.aof_current_size += nwritten;
+ server.aof_last_incr_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.aof_buf)+sdsavail(server.aof_buf)) < 4000) {
+ sdsclear(server.aof_buf);
+ } else {
+ sdsfree(server.aof_buf);
+ server.aof_buf = sdsempty();
+ }
+
+try_fsync:
+ /* Don't fsync if no-appendfsync-on-rewrite is set to yes and there are
+ * children doing I/O in the background. */
+ if (server.aof_no_fsync_on_rewrite && hasActiveChildProcess())
+ return;
+
+ /* Perform the fsync if needed. */
+ if (server.aof_fsync == AOF_FSYNC_ALWAYS) {
+ /* redis_fsync is defined as fdatasync() for Linux in order to avoid
+ * flushing metadata. */
+ latencyStartMonitor(latency);
+ /* Let's try to get this data on the disk. To guarantee data safe when
+ * the AOF fsync policy is 'always', we should exit if failed to fsync
+ * AOF (see comment next to the exit(1) after write error above). */
+ if (redis_fsync(server.aof_fd) == -1) {
+ serverLog(LL_WARNING,"Can't persist AOF for fsync error when the "
+ "AOF fsync policy is 'always': %s. Exiting...", strerror(errno));
+ exit(1);
+ }
+ latencyEndMonitor(latency);
+ latencyAddSampleIfNeeded("aof-fsync-always",latency);
+ server.aof_last_incr_fsync_offset = server.aof_last_incr_size;
+ server.aof_last_fsync = server.unixtime;
+ atomicSet(server.fsynced_reploff_pending, server.master_repl_offset);
+ } 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_incr_fsync_offset = server.aof_last_incr_size;
+ }
+ server.aof_last_fsync = server.unixtime;
+ }
+}
+
+sds catAppendOnlyGenericCommand(sds dst, int argc, robj **argv) {
+ char buf[32];
+ int len, j;
+ robj *o;
+
+ buf[0] = '*';
+ len = 1+ll2string(buf+1,sizeof(buf)-1,argc);
+ buf[len++] = '\r';
+ buf[len++] = '\n';
+ dst = sdscatlen(dst,buf,len);
+
+ for (j = 0; j < argc; j++) {
+ o = getDecodedObject(argv[j]);
+ buf[0] = '$';
+ len = 1+ll2string(buf+1,sizeof(buf)-1,sdslen(o->ptr));
+ buf[len++] = '\r';
+ buf[len++] = '\n';
+ dst = sdscatlen(dst,buf,len);
+ dst = sdscatlen(dst,o->ptr,sdslen(o->ptr));
+ dst = sdscatlen(dst,"\r\n",2);
+ decrRefCount(o);
+ }
+ return dst;
+}
+
+/* Generate a piece of timestamp annotation for AOF if current record timestamp
+ * in AOF is not equal server unix time. If we specify 'force' argument to 1,
+ * we would generate one without check, currently, it is useful in AOF rewriting
+ * child process which always needs to record one timestamp at the beginning of
+ * rewriting AOF.
+ *
+ * Timestamp annotation format is "#TS:${timestamp}\r\n". "TS" is short of
+ * timestamp and this method could save extra bytes in AOF. */
+sds genAofTimestampAnnotationIfNeeded(int force) {
+ sds ts = NULL;
+
+ if (force || server.aof_cur_timestamp < server.unixtime) {
+ server.aof_cur_timestamp = force ? time(NULL) : server.unixtime;
+ ts = sdscatfmt(sdsempty(), "#TS:%I\r\n", server.aof_cur_timestamp);
+ serverAssert(sdslen(ts) <= AOF_ANNOTATION_LINE_MAX_LEN);
+ }
+ return ts;
+}
+
+/* Write the given command to the aof file.
+ * dictid - dictionary id the command should be applied to,
+ * this is used in order to decide if a `select` command
+ * should also be written to the aof. Value of -1 means
+ * to avoid writing `select` command in any case.
+ * argv - The command to write to the aof.
+ * argc - Number of values in argv
+ */
+void feedAppendOnlyFile(int dictid, robj **argv, int argc) {
+ sds buf = sdsempty();
+
+ serverAssert(dictid == -1 || (dictid >= 0 && dictid < server.dbnum));
+
+ /* Feed timestamp if needed */
+ if (server.aof_timestamp_enabled) {
+ sds ts = genAofTimestampAnnotationIfNeeded(0);
+ if (ts != NULL) {
+ buf = sdscatsds(buf, ts);
+ sdsfree(ts);
+ }
+ }
+
+ /* The DB this command was targeting is not the same as the last command
+ * we appended. To issue a SELECT command is needed. */
+ if (dictid != -1 && 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.aof_selected_db = dictid;
+ }
+
+ /* All commands should be propagated the same way in AOF as in replication.
+ * No need for AOF-specific translation. */
+ buf = catAppendOnlyGenericCommand(buf,argc,argv);
+
+ /* 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. */
+ if (server.aof_state == AOF_ON ||
+ (server.aof_state == AOF_WAIT_REWRITE && server.child_type == CHILD_TYPE_AOF))
+ {
+ server.aof_buf = sdscatlen(server.aof_buf, buf, sdslen(buf));
+ }
+
+ sdsfree(buf);
+}
+
+/* ----------------------------------------------------------------------------
+ * AOF loading
+ * ------------------------------------------------------------------------- */
+
+/* In Redis commands are always executed in the context of a client, so in
+ * order to load the append only file we need to create a fake client. */
+struct client *createAOFClient(void) {
+ struct client *c = createClient(NULL);
+
+ c->id = CLIENT_ID_AOF; /* So modules can identify it's the AOF client. */
+
+ /*
+ * The AOF client should never be blocked (unlike master
+ * replication connection).
+ * This is because blocking the AOF client might cause
+ * deadlock (because potentially no one will unblock it).
+ * Also, if the AOF client will be blocked just for
+ * background processing there is a chance that the
+ * command execution order will be violated.
+ */
+ c->flags = CLIENT_DENY_BLOCKING;
+
+ /* We set the fake client as a slave waiting for the synchronization
+ * so that Redis will not try to send replies to this client. */
+ c->replstate = SLAVE_STATE_WAIT_BGSAVE_START;
+ return c;
+}
+
+/* Replay an append log file. On success AOF_OK or AOF_TRUNCATED is returned,
+ * otherwise, one of the following is returned:
+ * AOF_OPEN_ERR: Failed to open the AOF file.
+ * AOF_NOT_EXIST: AOF file doesn't exist.
+ * AOF_EMPTY: The AOF file is empty (nothing to load).
+ * AOF_FAILED: Failed to load the AOF file. */
+int loadSingleAppendOnlyFile(char *filename) {
+ struct client *fakeClient;
+ struct redis_stat sb;
+ int old_aof_state = server.aof_state;
+ long loops = 0;
+ off_t valid_up_to = 0; /* Offset of latest well-formed command loaded. */
+ off_t valid_before_multi = 0; /* Offset before MULTI command loaded. */
+ off_t last_progress_report_size = 0;
+ int ret = AOF_OK;
+
+ sds aof_filepath = makePath(server.aof_dirname, filename);
+ FILE *fp = fopen(aof_filepath, "r");
+ if (fp == NULL) {
+ int en = errno;
+ if (redis_stat(aof_filepath, &sb) == 0 || errno != ENOENT) {
+ serverLog(LL_WARNING,"Fatal error: can't open the append log file %s for reading: %s", filename, strerror(en));
+ sdsfree(aof_filepath);
+ return AOF_OPEN_ERR;
+ } else {
+ serverLog(LL_WARNING,"The append log file %s doesn't exist: %s", filename, strerror(errno));
+ sdsfree(aof_filepath);
+ return AOF_NOT_EXIST;
+ }
+ }
+
+ if (fp && redis_fstat(fileno(fp),&sb) != -1 && sb.st_size == 0) {
+ fclose(fp);
+ sdsfree(aof_filepath);
+ return AOF_EMPTY;
+ }
+
+ /* Temporarily disable AOF, to prevent EXEC from feeding a MULTI
+ * to the same file we're about to read. */
+ server.aof_state = AOF_OFF;
+
+ client *old_cur_client = server.current_client;
+ client *old_exec_client = server.executing_client;
+ fakeClient = createAOFClient();
+ server.current_client = server.executing_client = fakeClient;
+
+ /* Check if the AOF file is in RDB format (it may be RDB encoded base AOF
+ * or old style RDB-preamble AOF). In that case we need to load the RDB file
+ * and later continue loading the AOF tail if it is an old style RDB-preamble AOF. */
+ char sig[5]; /* "REDIS" */
+ if (fread(sig,1,5,fp) != 5 || memcmp(sig,"REDIS",5) != 0) {
+ /* Not in RDB format, seek back at 0 offset. */
+ if (fseek(fp,0,SEEK_SET) == -1) goto readerr;
+ } else {
+ /* RDB format. Pass loading the RDB functions. */
+ rio rdb;
+ int old_style = !strcmp(filename, server.aof_filename);
+ if (old_style)
+ serverLog(LL_NOTICE, "Reading RDB preamble from AOF file...");
+ else
+ serverLog(LL_NOTICE, "Reading RDB base file on AOF loading...");
+
+ if (fseek(fp,0,SEEK_SET) == -1) goto readerr;
+ rioInitWithFile(&rdb,fp);
+ if (rdbLoadRio(&rdb,RDBFLAGS_AOF_PREAMBLE,NULL) != C_OK) {
+ if (old_style)
+ serverLog(LL_WARNING, "Error reading the RDB preamble of the AOF file %s, AOF loading aborted", filename);
+ else
+ serverLog(LL_WARNING, "Error reading the RDB base file %s, AOF loading aborted", filename);
+
+ ret = AOF_FAILED;
+ goto cleanup;
+ } else {
+ loadingAbsProgress(ftello(fp));
+ last_progress_report_size = ftello(fp);
+ if (old_style) serverLog(LL_NOTICE, "Reading the remaining AOF tail...");
+ }
+ }
+
+ /* Read the actual AOF file, in REPL format, command by command. */
+ while(1) {
+ int argc, j;
+ unsigned long len;
+ robj **argv;
+ char buf[AOF_ANNOTATION_LINE_MAX_LEN];
+ sds argsds;
+ struct redisCommand *cmd;
+
+ /* Serve the clients from time to time */
+ if (!(loops++ % 1024)) {
+ off_t progress_delta = ftello(fp) - last_progress_report_size;
+ loadingIncrProgress(progress_delta);
+ last_progress_report_size += progress_delta;
+ processEventsWhileBlocked();
+ processModuleLoadingProgressEvent(1);
+ }
+ if (fgets(buf,sizeof(buf),fp) == NULL) {
+ if (feof(fp)) {
+ break;
+ } else {
+ goto readerr;
+ }
+ }
+ if (buf[0] == '#') continue; /* Skip annotations */
+ if (buf[0] != '*') goto fmterr;
+ if (buf[1] == '\0') goto readerr;
+ argc = atoi(buf+1);
+ if (argc < 1) goto fmterr;
+ if ((size_t)argc > SIZE_MAX / sizeof(robj*)) goto fmterr;
+
+ /* Load the next command in the AOF as our fake client
+ * argv. */
+ argv = zmalloc(sizeof(robj*)*argc);
+ fakeClient->argc = argc;
+ fakeClient->argv = argv;
+ fakeClient->argv_len = argc;
+
+ for (j = 0; j < argc; j++) {
+ /* Parse the argument len. */
+ char *readres = fgets(buf,sizeof(buf),fp);
+ if (readres == NULL || buf[0] != '$') {
+ fakeClient->argc = j; /* Free up to j-1. */
+ freeClientArgv(fakeClient);
+ if (readres == NULL)
+ goto readerr;
+ else
+ goto fmterr;
+ }
+ len = strtol(buf+1,NULL,10);
+
+ /* Read it into a string object. */
+ argsds = sdsnewlen(SDS_NOINIT,len);
+ if (len && fread(argsds,len,1,fp) == 0) {
+ sdsfree(argsds);
+ fakeClient->argc = j; /* Free up to j-1. */
+ freeClientArgv(fakeClient);
+ goto readerr;
+ }
+ argv[j] = createObject(OBJ_STRING,argsds);
+
+ /* Discard CRLF. */
+ if (fread(buf,2,1,fp) == 0) {
+ fakeClient->argc = j+1; /* Free up to j. */
+ freeClientArgv(fakeClient);
+ goto readerr;
+ }
+ }
+
+ /* Command lookup */
+ cmd = lookupCommand(argv,argc);
+ if (!cmd) {
+ serverLog(LL_WARNING,
+ "Unknown command '%s' reading the append only file %s",
+ (char*)argv[0]->ptr, filename);
+ freeClientArgv(fakeClient);
+ ret = AOF_FAILED;
+ goto cleanup;
+ }
+
+ if (cmd->proc == multiCommand) valid_before_multi = valid_up_to;
+
+ /* Run the command in the context of a fake client */
+ fakeClient->cmd = fakeClient->lastcmd = cmd;
+ if (fakeClient->flags & CLIENT_MULTI &&
+ fakeClient->cmd->proc != execCommand)
+ {
+ /* Note: we don't have to attempt calling evalGetCommandFlags,
+ * since this is AOF, the checks in processCommand are not made
+ * anyway.*/
+ queueMultiCommand(fakeClient, cmd->flags);
+ } else {
+ cmd->proc(fakeClient);
+ }
+
+ /* The fake client should not have a reply */
+ serverAssert(fakeClient->bufpos == 0 &&
+ listLength(fakeClient->reply) == 0);
+
+ /* The fake client should never get blocked */
+ serverAssert((fakeClient->flags & CLIENT_BLOCKED) == 0);
+
+ /* Clean up. Command code may have changed argv/argc so we use the
+ * argv/argc of the client instead of the local variables. */
+ freeClientArgv(fakeClient);
+ if (server.aof_load_truncated) valid_up_to = ftello(fp);
+ if (server.key_load_delay)
+ debugDelay(server.key_load_delay);
+ }
+
+ /* This point can only be reached when EOF is reached without errors.
+ * If the client is in the middle of a MULTI/EXEC, handle it as it was
+ * a short read, even if technically the protocol is correct: we want
+ * to remove the unprocessed tail and continue. */
+ if (fakeClient->flags & CLIENT_MULTI) {
+ serverLog(LL_WARNING,
+ "Revert incomplete MULTI/EXEC transaction in AOF file %s", filename);
+ valid_up_to = valid_before_multi;
+ goto uxeof;
+ }
+
+loaded_ok: /* DB loaded, cleanup and return success (AOF_OK or AOF_TRUNCATED). */
+ loadingIncrProgress(ftello(fp) - last_progress_report_size);
+ server.aof_state = old_aof_state;
+ goto cleanup;
+
+readerr: /* Read error. If feof(fp) is true, fall through to unexpected EOF. */
+ if (!feof(fp)) {
+ serverLog(LL_WARNING,"Unrecoverable error reading the append only file %s: %s", filename, strerror(errno));
+ ret = AOF_FAILED;
+ goto cleanup;
+ }
+
+uxeof: /* Unexpected AOF end of file. */
+ if (server.aof_load_truncated) {
+ serverLog(LL_WARNING,"!!! Warning: short read while loading the AOF file %s!!!", filename);
+ serverLog(LL_WARNING,"!!! Truncating the AOF %s at offset %llu !!!",
+ filename, (unsigned long long) valid_up_to);
+ if (valid_up_to == -1 || truncate(aof_filepath,valid_up_to) == -1) {
+ if (valid_up_to == -1) {
+ serverLog(LL_WARNING,"Last valid command offset is invalid");
+ } else {
+ serverLog(LL_WARNING,"Error truncating the AOF file %s: %s",
+ filename, strerror(errno));
+ }
+ } else {
+ /* Make sure the AOF file descriptor points to the end of the
+ * file after the truncate call. */
+ if (server.aof_fd != -1 && lseek(server.aof_fd,0,SEEK_END) == -1) {
+ serverLog(LL_WARNING,"Can't seek the end of the AOF file %s: %s",
+ filename, strerror(errno));
+ } else {
+ serverLog(LL_WARNING,
+ "AOF %s loaded anyway because aof-load-truncated is enabled", filename);
+ ret = AOF_TRUNCATED;
+ goto loaded_ok;
+ }
+ }
+ }
+ serverLog(LL_WARNING, "Unexpected end of file reading the append only file %s. You can: "
+ "1) Make a backup of your AOF file, then use ./redis-check-aof --fix <filename.manifest>. "
+ "2) Alternatively you can set the 'aof-load-truncated' configuration option to yes and restart the server.", filename);
+ ret = AOF_FAILED;
+ goto cleanup;
+
+fmterr: /* Format error. */
+ serverLog(LL_WARNING, "Bad file format reading the append only file %s: "
+ "make a backup of your AOF file, then use ./redis-check-aof --fix <filename.manifest>", filename);
+ ret = AOF_FAILED;
+ /* fall through to cleanup. */
+
+cleanup:
+ if (fakeClient) freeClient(fakeClient);
+ server.current_client = old_cur_client;
+ server.executing_client = old_exec_client;
+ fclose(fp);
+ sdsfree(aof_filepath);
+ return ret;
+}
+
+/* Load the AOF files according the aofManifest pointed by am. */
+int loadAppendOnlyFiles(aofManifest *am) {
+ serverAssert(am != NULL);
+ int status, ret = AOF_OK;
+ long long start;
+ off_t total_size = 0, base_size = 0;
+ sds aof_name;
+ int total_num, aof_num = 0, last_file;
+
+ /* If the 'server.aof_filename' file exists in dir, we may be starting
+ * from an old redis version. We will use enter upgrade mode in three situations.
+ *
+ * 1. If the 'server.aof_dirname' directory not exist
+ * 2. If the 'server.aof_dirname' directory exists but the manifest file is missing
+ * 3. If the 'server.aof_dirname' directory exists and the manifest file it contains
+ * has only one base AOF record, and the file name of this base AOF is 'server.aof_filename',
+ * and the 'server.aof_filename' file not exist in 'server.aof_dirname' directory
+ * */
+ if (fileExist(server.aof_filename)) {
+ if (!dirExists(server.aof_dirname) ||
+ (am->base_aof_info == NULL && listLength(am->incr_aof_list) == 0) ||
+ (am->base_aof_info != NULL && listLength(am->incr_aof_list) == 0 &&
+ !strcmp(am->base_aof_info->file_name, server.aof_filename) && !aofFileExist(server.aof_filename)))
+ {
+ aofUpgradePrepare(am);
+ }
+ }
+
+ if (am->base_aof_info == NULL && listLength(am->incr_aof_list) == 0) {
+ return AOF_NOT_EXIST;
+ }
+
+ total_num = getBaseAndIncrAppendOnlyFilesNum(am);
+ serverAssert(total_num > 0);
+
+ /* Here we calculate the total size of all BASE and INCR files in
+ * advance, it will be set to `server.loading_total_bytes`. */
+ total_size = getBaseAndIncrAppendOnlyFilesSize(am, &status);
+ if (status != AOF_OK) {
+ /* If an AOF exists in the manifest but not on the disk, we consider this to be a fatal error. */
+ if (status == AOF_NOT_EXIST) status = AOF_FAILED;
+
+ return status;
+ } else if (total_size == 0) {
+ return AOF_EMPTY;
+ }
+
+ startLoading(total_size, RDBFLAGS_AOF_PREAMBLE, 0);
+
+ /* Load BASE AOF if needed. */
+ if (am->base_aof_info) {
+ serverAssert(am->base_aof_info->file_type == AOF_FILE_TYPE_BASE);
+ aof_name = (char*)am->base_aof_info->file_name;
+ updateLoadingFileName(aof_name);
+ base_size = getAppendOnlyFileSize(aof_name, NULL);
+ last_file = ++aof_num == total_num;
+ start = ustime();
+ ret = loadSingleAppendOnlyFile(aof_name);
+ if (ret == AOF_OK || (ret == AOF_TRUNCATED && last_file)) {
+ serverLog(LL_NOTICE, "DB loaded from base file %s: %.3f seconds",
+ aof_name, (float)(ustime()-start)/1000000);
+ }
+
+ /* If the truncated file is not the last file, we consider this to be a fatal error. */
+ if (ret == AOF_TRUNCATED && !last_file) {
+ ret = AOF_FAILED;
+ serverLog(LL_WARNING, "Fatal error: the truncated file is not the last file");
+ }
+
+ if (ret == AOF_OPEN_ERR || ret == AOF_FAILED) {
+ goto cleanup;
+ }
+ }
+
+ /* Load INCR AOFs if needed. */
+ if (listLength(am->incr_aof_list)) {
+ listNode *ln;
+ listIter li;
+
+ listRewind(am->incr_aof_list, &li);
+ while ((ln = listNext(&li)) != NULL) {
+ aofInfo *ai = (aofInfo*)ln->value;
+ serverAssert(ai->file_type == AOF_FILE_TYPE_INCR);
+ aof_name = (char*)ai->file_name;
+ updateLoadingFileName(aof_name);
+ last_file = ++aof_num == total_num;
+ start = ustime();
+ ret = loadSingleAppendOnlyFile(aof_name);
+ if (ret == AOF_OK || (ret == AOF_TRUNCATED && last_file)) {
+ serverLog(LL_NOTICE, "DB loaded from incr file %s: %.3f seconds",
+ aof_name, (float)(ustime()-start)/1000000);
+ }
+
+ /* We know that (at least) one of the AOF files has data (total_size > 0),
+ * so empty incr AOF file doesn't count as a AOF_EMPTY result */
+ if (ret == AOF_EMPTY) ret = AOF_OK;
+
+ /* If the truncated file is not the last file, we consider this to be a fatal error. */
+ if (ret == AOF_TRUNCATED && !last_file) {
+ ret = AOF_FAILED;
+ serverLog(LL_WARNING, "Fatal error: the truncated file is not the last file");
+ }
+
+ if (ret == AOF_OPEN_ERR || ret == AOF_FAILED) {
+ goto cleanup;
+ }
+ }
+ }
+
+ server.aof_current_size = total_size;
+ /* Ideally, the aof_rewrite_base_size variable should hold the size of the
+ * AOF when the last rewrite ended, this should include the size of the
+ * incremental file that was created during the rewrite since otherwise we
+ * risk the next automatic rewrite to happen too soon (or immediately if
+ * auto-aof-rewrite-percentage is low). However, since we do not persist
+ * aof_rewrite_base_size information anywhere, we initialize it on restart
+ * to the size of BASE AOF file. This might cause the first AOFRW to be
+ * executed early, but that shouldn't be a problem since everything will be
+ * fine after the first AOFRW. */
+ server.aof_rewrite_base_size = base_size;
+
+cleanup:
+ stopLoading(ret == AOF_OK || ret == AOF_TRUNCATED);
+ return ret;
+}
+
+/* ----------------------------------------------------------------------------
+ * AOF rewrite
+ * ------------------------------------------------------------------------- */
+
+/* Delegate writing an object to writing a bulk string or bulk long long.
+ * This is not placed in rio.c since that adds the server.h dependency. */
+int rioWriteBulkObject(rio *r, robj *obj) {
+ /* Avoid using getDecodedObject to help copy-on-write (we are often
+ * in a child process when this function is called). */
+ if (obj->encoding == OBJ_ENCODING_INT) {
+ return rioWriteBulkLongLong(r,(long)obj->ptr);
+ } else if (sdsEncodedObject(obj)) {
+ return rioWriteBulkString(r,obj->ptr,sdslen(obj->ptr));
+ } else {
+ serverPanic("Unknown string encoding");
+ }
+}
+
+/* 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);
+
+ listTypeIterator *li = listTypeInitIterator(o,0,LIST_TAIL);
+ listTypeEntry entry;
+ while (listTypeNext(li,&entry)) {
+ if (count == 0) {
+ int cmd_items = (items > AOF_REWRITE_ITEMS_PER_CMD) ?
+ AOF_REWRITE_ITEMS_PER_CMD : items;
+ if (!rioWriteBulkCount(r,'*',2+cmd_items) ||
+ !rioWriteBulkString(r,"RPUSH",5) ||
+ !rioWriteBulkObject(r,key))
+ {
+ listTypeReleaseIterator(li);
+ return 0;
+ }
+ }
+
+ unsigned char *vstr;
+ size_t vlen;
+ long long lval;
+ vstr = listTypeGetValue(&entry,&vlen,&lval);
+ if (vstr) {
+ if (!rioWriteBulkString(r,(char*)vstr,vlen)) {
+ listTypeReleaseIterator(li);
+ return 0;
+ }
+ } else {
+ if (!rioWriteBulkLongLong(r,lval)) {
+ listTypeReleaseIterator(li);
+ return 0;
+ }
+ }
+ if (++count == AOF_REWRITE_ITEMS_PER_CMD) count = 0;
+ items--;
+ }
+ listTypeReleaseIterator(li);
+ 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);
+ setTypeIterator *si = setTypeInitIterator(o);
+ char *str;
+ size_t len;
+ int64_t llval;
+ while (setTypeNext(si, &str, &len, &llval) != -1) {
+ if (count == 0) {
+ int cmd_items = (items > AOF_REWRITE_ITEMS_PER_CMD) ?
+ AOF_REWRITE_ITEMS_PER_CMD : items;
+ if (!rioWriteBulkCount(r,'*',2+cmd_items) ||
+ !rioWriteBulkString(r,"SADD",4) ||
+ !rioWriteBulkObject(r,key))
+ {
+ return 0;
+ }
+ }
+ size_t written = str ?
+ rioWriteBulkString(r, str, len) : rioWriteBulkLongLong(r, llval);
+ if (!written) {
+ setTypeReleaseIterator(si);
+ return 0;
+ }
+ if (++count == AOF_REWRITE_ITEMS_PER_CMD) count = 0;
+ items--;
+ }
+ setTypeReleaseIterator(si);
+ 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 == OBJ_ENCODING_LISTPACK) {
+ unsigned char *zl = o->ptr;
+ unsigned char *eptr, *sptr;
+ unsigned char *vstr;
+ unsigned int vlen;
+ long long vll;
+ double score;
+
+ eptr = lpSeek(zl,0);
+ serverAssert(eptr != NULL);
+ sptr = lpNext(zl,eptr);
+ serverAssert(sptr != NULL);
+
+ while (eptr != NULL) {
+ vstr = lpGetValue(eptr,&vlen,&vll);
+ score = zzlGetScore(sptr);
+
+ if (count == 0) {
+ int cmd_items = (items > AOF_REWRITE_ITEMS_PER_CMD) ?
+ AOF_REWRITE_ITEMS_PER_CMD : items;
+
+ if (!rioWriteBulkCount(r,'*',2+cmd_items*2) ||
+ !rioWriteBulkString(r,"ZADD",4) ||
+ !rioWriteBulkObject(r,key))
+ {
+ return 0;
+ }
+ }
+ if (!rioWriteBulkDouble(r,score)) return 0;
+ if (vstr != NULL) {
+ if (!rioWriteBulkString(r,(char*)vstr,vlen)) return 0;
+ } else {
+ if (!rioWriteBulkLongLong(r,vll)) return 0;
+ }
+ zzlNext(zl,&eptr,&sptr);
+ if (++count == AOF_REWRITE_ITEMS_PER_CMD) count = 0;
+ items--;
+ }
+ } else if (o->encoding == OBJ_ENCODING_SKIPLIST) {
+ zset *zs = o->ptr;
+ dictIterator *di = dictGetIterator(zs->dict);
+ dictEntry *de;
+
+ while((de = dictNext(di)) != NULL) {
+ sds ele = dictGetKey(de);
+ double *score = dictGetVal(de);
+
+ if (count == 0) {
+ int cmd_items = (items > AOF_REWRITE_ITEMS_PER_CMD) ?
+ AOF_REWRITE_ITEMS_PER_CMD : items;
+
+ if (!rioWriteBulkCount(r,'*',2+cmd_items*2) ||
+ !rioWriteBulkString(r,"ZADD",4) ||
+ !rioWriteBulkObject(r,key))
+ {
+ dictReleaseIterator(di);
+ return 0;
+ }
+ }
+ if (!rioWriteBulkDouble(r,*score) ||
+ !rioWriteBulkString(r,ele,sdslen(ele)))
+ {
+ dictReleaseIterator(di);
+ return 0;
+ }
+ if (++count == AOF_REWRITE_ITEMS_PER_CMD) count = 0;
+ items--;
+ }
+ dictReleaseIterator(di);
+ } else {
+ serverPanic("Unknown sorted zset encoding");
+ }
+ return 1;
+}
+
+/* Write either the key or the value of the currently selected item of a 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 OBJ_HASH_KEY or OBJ_HASH_VALUE.
+ *
+ * The function returns 0 on error, non-zero on success. */
+static int rioWriteHashIteratorCursor(rio *r, hashTypeIterator *hi, int what) {
+ if (hi->encoding == OBJ_ENCODING_LISTPACK) {
+ unsigned char *vstr = NULL;
+ unsigned int vlen = UINT_MAX;
+ long long vll = LLONG_MAX;
+
+ hashTypeCurrentFromListpack(hi, what, &vstr, &vlen, &vll);
+ if (vstr)
+ return rioWriteBulkString(r, (char*)vstr, vlen);
+ else
+ return rioWriteBulkLongLong(r, vll);
+ } else if (hi->encoding == OBJ_ENCODING_HT) {
+ sds value = hashTypeCurrentFromHashTable(hi, what);
+ return rioWriteBulkString(r, value, sdslen(value));
+ }
+
+ serverPanic("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) != C_ERR) {
+ if (count == 0) {
+ int cmd_items = (items > AOF_REWRITE_ITEMS_PER_CMD) ?
+ AOF_REWRITE_ITEMS_PER_CMD : items;
+
+ if (!rioWriteBulkCount(r,'*',2+cmd_items*2) ||
+ !rioWriteBulkString(r,"HMSET",5) ||
+ !rioWriteBulkObject(r,key))
+ {
+ hashTypeReleaseIterator(hi);
+ return 0;
+ }
+ }
+
+ if (!rioWriteHashIteratorCursor(r, hi, OBJ_HASH_KEY) ||
+ !rioWriteHashIteratorCursor(r, hi, OBJ_HASH_VALUE))
+ {
+ hashTypeReleaseIterator(hi);
+ return 0;
+ }
+ if (++count == AOF_REWRITE_ITEMS_PER_CMD) count = 0;
+ items--;
+ }
+
+ hashTypeReleaseIterator(hi);
+
+ return 1;
+}
+
+/* Helper for rewriteStreamObject() that generates a bulk string into the
+ * AOF representing the ID 'id'. */
+int rioWriteBulkStreamID(rio *r,streamID *id) {
+ int retval;
+
+ sds replyid = sdscatfmt(sdsempty(),"%U-%U",id->ms,id->seq);
+ retval = rioWriteBulkString(r,replyid,sdslen(replyid));
+ sdsfree(replyid);
+ return retval;
+}
+
+/* Helper for rewriteStreamObject(): emit the XCLAIM needed in order to
+ * add the message described by 'nack' having the id 'rawid', into the pending
+ * list of the specified consumer. All this in the context of the specified
+ * key and group. */
+int rioWriteStreamPendingEntry(rio *r, robj *key, const char *groupname, size_t groupname_len, streamConsumer *consumer, unsigned char *rawid, streamNACK *nack) {
+ /* XCLAIM <key> <group> <consumer> 0 <id> TIME <milliseconds-unix-time>
+ RETRYCOUNT <count> JUSTID FORCE. */
+ streamID id;
+ streamDecodeID(rawid,&id);
+ if (rioWriteBulkCount(r,'*',12) == 0) return 0;
+ if (rioWriteBulkString(r,"XCLAIM",6) == 0) return 0;
+ if (rioWriteBulkObject(r,key) == 0) return 0;
+ if (rioWriteBulkString(r,groupname,groupname_len) == 0) return 0;
+ if (rioWriteBulkString(r,consumer->name,sdslen(consumer->name)) == 0) return 0;
+ if (rioWriteBulkString(r,"0",1) == 0) return 0;
+ if (rioWriteBulkStreamID(r,&id) == 0) return 0;
+ if (rioWriteBulkString(r,"TIME",4) == 0) return 0;
+ if (rioWriteBulkLongLong(r,nack->delivery_time) == 0) return 0;
+ if (rioWriteBulkString(r,"RETRYCOUNT",10) == 0) return 0;
+ if (rioWriteBulkLongLong(r,nack->delivery_count) == 0) return 0;
+ if (rioWriteBulkString(r,"JUSTID",6) == 0) return 0;
+ if (rioWriteBulkString(r,"FORCE",5) == 0) return 0;
+ return 1;
+}
+
+/* Helper for rewriteStreamObject(): emit the XGROUP CREATECONSUMER is
+ * needed in order to create consumers that do not have any pending entries.
+ * All this in the context of the specified key and group. */
+int rioWriteStreamEmptyConsumer(rio *r, robj *key, const char *groupname, size_t groupname_len, streamConsumer *consumer) {
+ /* XGROUP CREATECONSUMER <key> <group> <consumer> */
+ if (rioWriteBulkCount(r,'*',5) == 0) return 0;
+ if (rioWriteBulkString(r,"XGROUP",6) == 0) return 0;
+ if (rioWriteBulkString(r,"CREATECONSUMER",14) == 0) return 0;
+ if (rioWriteBulkObject(r,key) == 0) return 0;
+ if (rioWriteBulkString(r,groupname,groupname_len) == 0) return 0;
+ if (rioWriteBulkString(r,consumer->name,sdslen(consumer->name)) == 0) return 0;
+ return 1;
+}
+
+/* Emit the commands needed to rebuild a stream object.
+ * The function returns 0 on error, 1 on success. */
+int rewriteStreamObject(rio *r, robj *key, robj *o) {
+ stream *s = o->ptr;
+ streamIterator si;
+ streamIteratorStart(&si,s,NULL,NULL,0);
+ streamID id;
+ int64_t numfields;
+
+ if (s->length) {
+ /* Reconstruct the stream data using XADD commands. */
+ while(streamIteratorGetID(&si,&id,&numfields)) {
+ /* Emit a two elements array for each item. The first is
+ * the ID, the second is an array of field-value pairs. */
+
+ /* Emit the XADD <key> <id> ...fields... command. */
+ if (!rioWriteBulkCount(r,'*',3+numfields*2) ||
+ !rioWriteBulkString(r,"XADD",4) ||
+ !rioWriteBulkObject(r,key) ||
+ !rioWriteBulkStreamID(r,&id))
+ {
+ streamIteratorStop(&si);
+ return 0;
+ }
+ while(numfields--) {
+ unsigned char *field, *value;
+ int64_t field_len, value_len;
+ streamIteratorGetField(&si,&field,&value,&field_len,&value_len);
+ if (!rioWriteBulkString(r,(char*)field,field_len) ||
+ !rioWriteBulkString(r,(char*)value,value_len))
+ {
+ streamIteratorStop(&si);
+ return 0;
+ }
+ }
+ }
+ } else {
+ /* Use the XADD MAXLEN 0 trick to generate an empty stream if
+ * the key we are serializing is an empty string, which is possible
+ * for the Stream type. */
+ id.ms = 0; id.seq = 1;
+ if (!rioWriteBulkCount(r,'*',7) ||
+ !rioWriteBulkString(r,"XADD",4) ||
+ !rioWriteBulkObject(r,key) ||
+ !rioWriteBulkString(r,"MAXLEN",6) ||
+ !rioWriteBulkString(r,"0",1) ||
+ !rioWriteBulkStreamID(r,&id) ||
+ !rioWriteBulkString(r,"x",1) ||
+ !rioWriteBulkString(r,"y",1))
+ {
+ streamIteratorStop(&si);
+ return 0;
+ }
+ }
+
+ /* Append XSETID after XADD, make sure lastid is correct,
+ * in case of XDEL lastid. */
+ if (!rioWriteBulkCount(r,'*',7) ||
+ !rioWriteBulkString(r,"XSETID",6) ||
+ !rioWriteBulkObject(r,key) ||
+ !rioWriteBulkStreamID(r,&s->last_id) ||
+ !rioWriteBulkString(r,"ENTRIESADDED",12) ||
+ !rioWriteBulkLongLong(r,s->entries_added) ||
+ !rioWriteBulkString(r,"MAXDELETEDID",12) ||
+ !rioWriteBulkStreamID(r,&s->max_deleted_entry_id))
+ {
+ streamIteratorStop(&si);
+ return 0;
+ }
+
+
+ /* Create all the stream consumer groups. */
+ if (s->cgroups) {
+ raxIterator ri;
+ raxStart(&ri,s->cgroups);
+ raxSeek(&ri,"^",NULL,0);
+ while(raxNext(&ri)) {
+ streamCG *group = ri.data;
+ /* Emit the XGROUP CREATE in order to create the group. */
+ if (!rioWriteBulkCount(r,'*',7) ||
+ !rioWriteBulkString(r,"XGROUP",6) ||
+ !rioWriteBulkString(r,"CREATE",6) ||
+ !rioWriteBulkObject(r,key) ||
+ !rioWriteBulkString(r,(char*)ri.key,ri.key_len) ||
+ !rioWriteBulkStreamID(r,&group->last_id) ||
+ !rioWriteBulkString(r,"ENTRIESREAD",11) ||
+ !rioWriteBulkLongLong(r,group->entries_read))
+ {
+ raxStop(&ri);
+ streamIteratorStop(&si);
+ return 0;
+ }
+
+ /* Generate XCLAIMs for each consumer that happens to
+ * have pending entries. Empty consumers would be generated with
+ * XGROUP CREATECONSUMER. */
+ raxIterator ri_cons;
+ raxStart(&ri_cons,group->consumers);
+ raxSeek(&ri_cons,"^",NULL,0);
+ while(raxNext(&ri_cons)) {
+ streamConsumer *consumer = ri_cons.data;
+ /* If there are no pending entries, just emit XGROUP CREATECONSUMER */
+ if (raxSize(consumer->pel) == 0) {
+ if (rioWriteStreamEmptyConsumer(r,key,(char*)ri.key,
+ ri.key_len,consumer) == 0)
+ {
+ raxStop(&ri_cons);
+ raxStop(&ri);
+ streamIteratorStop(&si);
+ return 0;
+ }
+ continue;
+ }
+ /* For the current consumer, iterate all the PEL entries
+ * to emit the XCLAIM protocol. */
+ raxIterator ri_pel;
+ raxStart(&ri_pel,consumer->pel);
+ raxSeek(&ri_pel,"^",NULL,0);
+ while(raxNext(&ri_pel)) {
+ streamNACK *nack = ri_pel.data;
+ if (rioWriteStreamPendingEntry(r,key,(char*)ri.key,
+ ri.key_len,consumer,
+ ri_pel.key,nack) == 0)
+ {
+ raxStop(&ri_pel);
+ raxStop(&ri_cons);
+ raxStop(&ri);
+ streamIteratorStop(&si);
+ return 0;
+ }
+ }
+ raxStop(&ri_pel);
+ }
+ raxStop(&ri_cons);
+ }
+ raxStop(&ri);
+ }
+
+ streamIteratorStop(&si);
+ return 1;
+}
+
+/* Call the module type callback in order to rewrite a data type
+ * that is exported by a module and is not handled by Redis itself.
+ * The function returns 0 on error, 1 on success. */
+int rewriteModuleObject(rio *r, robj *key, robj *o, int dbid) {
+ RedisModuleIO io;
+ moduleValue *mv = o->ptr;
+ moduleType *mt = mv->type;
+ moduleInitIOContext(io,mt,r,key,dbid);
+ mt->aof_rewrite(&io,key,mv->value);
+ if (io.ctx) {
+ moduleFreeContext(io.ctx);
+ zfree(io.ctx);
+ }
+ return io.error ? 0 : 1;
+}
+
+static int rewriteFunctions(rio *aof) {
+ dict *functions = functionsLibGet();
+ dictIterator *iter = dictGetIterator(functions);
+ dictEntry *entry = NULL;
+ while ((entry = dictNext(iter))) {
+ functionLibInfo *li = dictGetVal(entry);
+ if (rioWrite(aof, "*3\r\n", 4) == 0) goto werr;
+ char function_load[] = "$8\r\nFUNCTION\r\n$4\r\nLOAD\r\n";
+ if (rioWrite(aof, function_load, sizeof(function_load) - 1) == 0) goto werr;
+ if (rioWriteBulkString(aof, li->code, sdslen(li->code)) == 0) goto werr;
+ }
+ dictReleaseIterator(iter);
+ return 1;
+
+werr:
+ dictReleaseIterator(iter);
+ return 0;
+}
+
+int rewriteAppendOnlyFileRio(rio *aof) {
+ dictIterator *di = NULL;
+ dictEntry *de;
+ int j;
+ long key_count = 0;
+ long long updated_time = 0;
+
+ /* Record timestamp at the beginning of rewriting AOF. */
+ if (server.aof_timestamp_enabled) {
+ sds ts = genAofTimestampAnnotationIfNeeded(1);
+ if (rioWrite(aof,ts,sdslen(ts)) == 0) { sdsfree(ts); goto werr; }
+ sdsfree(ts);
+ }
+
+ if (rewriteFunctions(aof) == 0) goto werr;
+
+ 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 = dictGetSafeIterator(d);
+
+ /* SELECT the new DB */
+ if (rioWrite(aof,selectcmd,sizeof(selectcmd)-1) == 0) goto werr;
+ if (rioWriteBulkLongLong(aof,j) == 0) goto werr;
+
+ /* Iterate this DB writing every entry */
+ while((de = dictNext(di)) != NULL) {
+ sds keystr;
+ robj key, *o;
+ long long expiretime;
+ size_t aof_bytes_before_key = aof->processed_bytes;
+
+ keystr = dictGetKey(de);
+ o = dictGetVal(de);
+ initStaticStringObject(key,keystr);
+
+ expiretime = getExpire(db,&key);
+
+ /* Save the key and associated value */
+ if (o->type == OBJ_STRING) {
+ /* Emit a SET command */
+ char cmd[]="*3\r\n$3\r\nSET\r\n";
+ if (rioWrite(aof,cmd,sizeof(cmd)-1) == 0) goto werr;
+ /* Key and value */
+ if (rioWriteBulkObject(aof,&key) == 0) goto werr;
+ if (rioWriteBulkObject(aof,o) == 0) goto werr;
+ } else if (o->type == OBJ_LIST) {
+ if (rewriteListObject(aof,&key,o) == 0) goto werr;
+ } else if (o->type == OBJ_SET) {
+ if (rewriteSetObject(aof,&key,o) == 0) goto werr;
+ } else if (o->type == OBJ_ZSET) {
+ if (rewriteSortedSetObject(aof,&key,o) == 0) goto werr;
+ } else if (o->type == OBJ_HASH) {
+ if (rewriteHashObject(aof,&key,o) == 0) goto werr;
+ } else if (o->type == OBJ_STREAM) {
+ if (rewriteStreamObject(aof,&key,o) == 0) goto werr;
+ } else if (o->type == OBJ_MODULE) {
+ if (rewriteModuleObject(aof,&key,o,j) == 0) goto werr;
+ } else {
+ serverPanic("Unknown object type");
+ }
+
+ /* In fork child process, we can try to release memory back to the
+ * OS and possibly avoid or decrease COW. We give the dismiss
+ * mechanism a hint about an estimated size of the object we stored. */
+ size_t dump_size = aof->processed_bytes - aof_bytes_before_key;
+ if (server.in_fork_child) dismissObject(o, dump_size);
+
+ /* Save the expire time */
+ if (expiretime != -1) {
+ char cmd[]="*3\r\n$9\r\nPEXPIREAT\r\n";
+ if (rioWrite(aof,cmd,sizeof(cmd)-1) == 0) goto werr;
+ if (rioWriteBulkObject(aof,&key) == 0) goto werr;
+ if (rioWriteBulkLongLong(aof,expiretime) == 0) goto werr;
+ }
+
+ /* Update info every 1 second (approximately).
+ * in order to avoid calling mstime() on each iteration, we will
+ * check the diff every 1024 keys */
+ if ((key_count++ & 1023) == 0) {
+ long long now = mstime();
+ if (now - updated_time >= 1000) {
+ sendChildInfo(CHILD_INFO_TYPE_CURRENT_INFO, key_count, "AOF rewrite");
+ updated_time = now;
+ }
+ }
+
+ /* Delay before next key if required (for testing) */
+ if (server.rdb_key_save_delay)
+ debugDelay(server.rdb_key_save_delay);
+ }
+ dictReleaseIterator(di);
+ di = NULL;
+ }
+ return C_OK;
+
+werr:
+ if (di) dictReleaseIterator(di);
+ return C_ERR;
+}
+
+/* Write a sequence of commands able to fully rebuild the dataset into
+ * "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 AOF_REWRITE_ITEMS_PER_CMD items per time
+ * are inserted using a single command. */
+int rewriteAppendOnlyFile(char *filename) {
+ rio aof;
+ FILE *fp = NULL;
+ char tmpfile[256];
+
+ /* 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) {
+ serverLog(LL_WARNING, "Opening the temp file for AOF rewrite in rewriteAppendOnlyFile(): %s", strerror(errno));
+ return C_ERR;
+ }
+
+ rioInitWithFile(&aof,fp);
+
+ if (server.aof_rewrite_incremental_fsync) {
+ rioSetAutoSync(&aof,REDIS_AUTOSYNC_BYTES);
+ rioSetReclaimCache(&aof,1);
+ }
+
+ startSaving(RDBFLAGS_AOF_PREAMBLE);
+
+ if (server.aof_use_rdb_preamble) {
+ int error;
+ if (rdbSaveRio(SLAVE_REQ_NONE,&aof,&error,RDBFLAGS_AOF_PREAMBLE,NULL) == C_ERR) {
+ errno = error;
+ goto werr;
+ }
+ } else {
+ if (rewriteAppendOnlyFileRio(&aof) == C_ERR) goto werr;
+ }
+
+ /* Make sure data will not remain on the OS's output buffers */
+ if (fflush(fp)) goto werr;
+ if (fsync(fileno(fp))) goto werr;
+ if (reclaimFilePageCache(fileno(fp), 0, 0) == -1) {
+ /* A minor error. Just log to know what happens */
+ serverLog(LL_NOTICE,"Unable to reclaim page cache: %s", strerror(errno));
+ }
+ if (fclose(fp)) { fp = NULL; goto werr; }
+ fp = NULL;
+
+ /* Use RENAME to make sure the DB file is changed atomically only
+ * if the generate DB file is ok. */
+ if (rename(tmpfile,filename) == -1) {
+ serverLog(LL_WARNING,"Error moving temp append only file on the final destination: %s", strerror(errno));
+ unlink(tmpfile);
+ stopSaving(0);
+ return C_ERR;
+ }
+ stopSaving(1);
+
+ return C_OK;
+
+werr:
+ serverLog(LL_WARNING,"Write error writing append only file on disk: %s", strerror(errno));
+ if (fp) fclose(fp);
+ unlink(tmpfile);
+ stopSaving(0);
+ return C_ERR;
+}
+/* ----------------------------------------------------------------------------
+ * AOF background rewrite
+ * ------------------------------------------------------------------------- */
+
+/* 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 open a new INCR AOF file to continue writing.
+ * 3) When the child finished '2a' exists.
+ * 4) The parent will trap the exit code, if it's OK, it will:
+ * 4a) get a new BASE file name and mark the previous (if we have) as the HISTORY type
+ * 4b) rename(2) the temp file in new BASE file name
+ * 4c) mark the rewritten INCR AOFs as history type
+ * 4d) persist AOF manifest file
+ * 4e) Delete the history files use bio
+ */
+int rewriteAppendOnlyFileBackground(void) {
+ pid_t childpid;
+
+ if (hasActiveChildProcess()) return C_ERR;
+
+ if (dirCreateIfMissing(server.aof_dirname) == -1) {
+ serverLog(LL_WARNING, "Can't open or create append-only dir %s: %s",
+ server.aof_dirname, strerror(errno));
+ server.aof_lastbgrewrite_status = C_ERR;
+ return C_ERR;
+ }
+
+ /* We set aof_selected_db to -1 in order to force the next call to the
+ * feedAppendOnlyFile() to issue a SELECT command. */
+ server.aof_selected_db = -1;
+ flushAppendOnlyFile(1);
+ if (openNewIncrAofForAppend() != C_OK) {
+ server.aof_lastbgrewrite_status = C_ERR;
+ return C_ERR;
+ }
+
+ if (server.aof_state == AOF_WAIT_REWRITE) {
+ /* Wait for all bio jobs related to AOF to drain. This prevents a race
+ * between updates to `fsynced_reploff_pending` of the worker thread, belonging
+ * to the previous AOF, and the new one. This concern is specific for a full
+ * sync scenario where we don't wanna risk the ACKed replication offset
+ * jumping backwards or forward when switching to a different master. */
+ bioDrainWorker(BIO_AOF_FSYNC);
+
+ /* Set the initial repl_offset, which will be applied to fsynced_reploff
+ * when AOFRW finishes (after possibly being updated by a bio thread) */
+ atomicSet(server.fsynced_reploff_pending, server.master_repl_offset);
+ server.fsynced_reploff = 0;
+ }
+
+ server.stat_aof_rewrites++;
+
+ if ((childpid = redisFork(CHILD_TYPE_AOF)) == 0) {
+ char tmpfile[256];
+
+ /* Child */
+ redisSetProcTitle("redis-aof-rewrite");
+ redisSetCpuAffinity(server.aof_rewrite_cpulist);
+ snprintf(tmpfile,256,"temp-rewriteaof-bg-%d.aof", (int) getpid());
+ if (rewriteAppendOnlyFile(tmpfile) == C_OK) {
+ serverLog(LL_NOTICE,
+ "Successfully created the temporary AOF base file %s", tmpfile);
+ sendChildCowInfo(CHILD_INFO_TYPE_AOF_COW_SIZE, "AOF rewrite");
+ exitFromChild(0);
+ } else {
+ exitFromChild(1);
+ }
+ } else {
+ /* Parent */
+ if (childpid == -1) {
+ server.aof_lastbgrewrite_status = C_ERR;
+ serverLog(LL_WARNING,
+ "Can't rewrite append only file in background: fork: %s",
+ strerror(errno));
+ return C_ERR;
+ }
+ serverLog(LL_NOTICE,
+ "Background append only file rewriting started by pid %ld",(long) childpid);
+ server.aof_rewrite_scheduled = 0;
+ server.aof_rewrite_time_start = time(NULL);
+ return C_OK;
+ }
+ return C_OK; /* unreached */
+}
+
+void bgrewriteaofCommand(client *c) {
+ if (server.child_type == CHILD_TYPE_AOF) {
+ addReplyError(c,"Background append only file rewriting already in progress");
+ } else if (hasActiveChildProcess() || server.in_exec) {
+ server.aof_rewrite_scheduled = 1;
+ /* When manually triggering AOFRW we reset the count
+ * so that it can be executed immediately. */
+ server.stat_aofrw_consecutive_failures = 0;
+ addReplyStatus(c,"Background append only file rewriting scheduled");
+ } else if (rewriteAppendOnlyFileBackground() == C_OK) {
+ addReplyStatus(c,"Background append only file rewriting started");
+ } else {
+ addReplyError(c,"Can't execute an AOF background rewriting. "
+ "Please check the server logs for more information.");
+ }
+}
+
+void aofRemoveTempFile(pid_t childpid) {
+ char tmpfile[256];
+
+ snprintf(tmpfile,256,"temp-rewriteaof-bg-%d.aof", (int) childpid);
+ bg_unlink(tmpfile);
+
+ snprintf(tmpfile,256,"temp-rewriteaof-%d.aof", (int) childpid);
+ bg_unlink(tmpfile);
+}
+
+/* Get size of an AOF file.
+ * The status argument is an optional output argument to be filled with
+ * one of the AOF_ status values. */
+off_t getAppendOnlyFileSize(sds filename, int *status) {
+ struct redis_stat sb;
+ off_t size;
+ mstime_t latency;
+
+ sds aof_filepath = makePath(server.aof_dirname, filename);
+ latencyStartMonitor(latency);
+ if (redis_stat(aof_filepath, &sb) == -1) {
+ if (status) *status = errno == ENOENT ? AOF_NOT_EXIST : AOF_OPEN_ERR;
+ serverLog(LL_WARNING, "Unable to obtain the AOF file %s length. stat: %s",
+ filename, strerror(errno));
+ size = 0;
+ } else {
+ if (status) *status = AOF_OK;
+ size = sb.st_size;
+ }
+ latencyEndMonitor(latency);
+ latencyAddSampleIfNeeded("aof-fstat", latency);
+ sdsfree(aof_filepath);
+ return size;
+}
+
+/* Get size of all AOF files referred by the manifest (excluding history).
+ * The status argument is an output argument to be filled with
+ * one of the AOF_ status values. */
+off_t getBaseAndIncrAppendOnlyFilesSize(aofManifest *am, int *status) {
+ off_t size = 0;
+ listNode *ln;
+ listIter li;
+
+ if (am->base_aof_info) {
+ serverAssert(am->base_aof_info->file_type == AOF_FILE_TYPE_BASE);
+
+ size += getAppendOnlyFileSize(am->base_aof_info->file_name, status);
+ if (*status != AOF_OK) return 0;
+ }
+
+ listRewind(am->incr_aof_list, &li);
+ while ((ln = listNext(&li)) != NULL) {
+ aofInfo *ai = (aofInfo*)ln->value;
+ serverAssert(ai->file_type == AOF_FILE_TYPE_INCR);
+ size += getAppendOnlyFileSize(ai->file_name, status);
+ if (*status != AOF_OK) return 0;
+ }
+
+ return size;
+}
+
+int getBaseAndIncrAppendOnlyFilesNum(aofManifest *am) {
+ int num = 0;
+ if (am->base_aof_info) num++;
+ if (am->incr_aof_list) num += listLength(am->incr_aof_list);
+ return num;
+}
+
+/* A background append only file rewriting (BGREWRITEAOF) terminated its work.
+ * Handle this. */
+void backgroundRewriteDoneHandler(int exitcode, int bysignal) {
+ if (!bysignal && exitcode == 0) {
+ char tmpfile[256];
+ long long now = ustime();
+ sds new_base_filepath = NULL;
+ sds new_incr_filepath = NULL;
+ aofManifest *temp_am;
+ mstime_t latency;
+
+ serverLog(LL_NOTICE,
+ "Background AOF rewrite terminated with success");
+
+ snprintf(tmpfile, 256, "temp-rewriteaof-bg-%d.aof",
+ (int)server.child_pid);
+
+ serverAssert(server.aof_manifest != NULL);
+
+ /* Dup a temporary aof_manifest for subsequent modifications. */
+ temp_am = aofManifestDup(server.aof_manifest);
+
+ /* Get a new BASE file name and mark the previous (if we have)
+ * as the HISTORY type. */
+ sds new_base_filename = getNewBaseFileNameAndMarkPreAsHistory(temp_am);
+ serverAssert(new_base_filename != NULL);
+ new_base_filepath = makePath(server.aof_dirname, new_base_filename);
+
+ /* Rename the temporary aof file to 'new_base_filename'. */
+ latencyStartMonitor(latency);
+ if (rename(tmpfile, new_base_filepath) == -1) {
+ serverLog(LL_WARNING,
+ "Error trying to rename the temporary AOF base file %s into %s: %s",
+ tmpfile,
+ new_base_filepath,
+ strerror(errno));
+ aofManifestFree(temp_am);
+ sdsfree(new_base_filepath);
+ server.aof_lastbgrewrite_status = C_ERR;
+ server.stat_aofrw_consecutive_failures++;
+ goto cleanup;
+ }
+ latencyEndMonitor(latency);
+ latencyAddSampleIfNeeded("aof-rename", latency);
+ serverLog(LL_NOTICE,
+ "Successfully renamed the temporary AOF base file %s into %s", tmpfile, new_base_filename);
+
+ /* Rename the temporary incr aof file to 'new_incr_filename'. */
+ if (server.aof_state == AOF_WAIT_REWRITE) {
+ /* Get temporary incr aof name. */
+ sds temp_incr_aof_name = getTempIncrAofName();
+ sds temp_incr_filepath = makePath(server.aof_dirname, temp_incr_aof_name);
+ /* Get next new incr aof name. */
+ sds new_incr_filename = getNewIncrAofName(temp_am);
+ new_incr_filepath = makePath(server.aof_dirname, new_incr_filename);
+ latencyStartMonitor(latency);
+ if (rename(temp_incr_filepath, new_incr_filepath) == -1) {
+ serverLog(LL_WARNING,
+ "Error trying to rename the temporary AOF incr file %s into %s: %s",
+ temp_incr_filepath,
+ new_incr_filepath,
+ strerror(errno));
+ bg_unlink(new_base_filepath);
+ sdsfree(new_base_filepath);
+ aofManifestFree(temp_am);
+ sdsfree(temp_incr_filepath);
+ sdsfree(new_incr_filepath);
+ sdsfree(temp_incr_aof_name);
+ server.aof_lastbgrewrite_status = C_ERR;
+ server.stat_aofrw_consecutive_failures++;
+ goto cleanup;
+ }
+ latencyEndMonitor(latency);
+ latencyAddSampleIfNeeded("aof-rename", latency);
+ serverLog(LL_NOTICE,
+ "Successfully renamed the temporary AOF incr file %s into %s", temp_incr_aof_name, new_incr_filename);
+ sdsfree(temp_incr_filepath);
+ sdsfree(temp_incr_aof_name);
+ }
+
+ /* Change the AOF file type in 'incr_aof_list' from AOF_FILE_TYPE_INCR
+ * to AOF_FILE_TYPE_HIST, and move them to the 'history_aof_list'. */
+ markRewrittenIncrAofAsHistory(temp_am);
+
+ /* Persist our modifications. */
+ if (persistAofManifest(temp_am) == C_ERR) {
+ bg_unlink(new_base_filepath);
+ aofManifestFree(temp_am);
+ sdsfree(new_base_filepath);
+ if (new_incr_filepath) {
+ bg_unlink(new_incr_filepath);
+ sdsfree(new_incr_filepath);
+ }
+ server.aof_lastbgrewrite_status = C_ERR;
+ server.stat_aofrw_consecutive_failures++;
+ goto cleanup;
+ }
+ sdsfree(new_base_filepath);
+ if (new_incr_filepath) sdsfree(new_incr_filepath);
+
+ /* We can safely let `server.aof_manifest` point to 'temp_am' and free the previous one. */
+ aofManifestFreeAndUpdate(temp_am);
+
+ if (server.aof_state != AOF_OFF) {
+ /* AOF enabled. */
+ server.aof_current_size = getAppendOnlyFileSize(new_base_filename, NULL) + server.aof_last_incr_size;
+ server.aof_rewrite_base_size = server.aof_current_size;
+ }
+
+ /* We don't care about the return value of `aofDelHistoryFiles`, because the history
+ * deletion failure will not cause any problems. */
+ aofDelHistoryFiles();
+
+ server.aof_lastbgrewrite_status = C_OK;
+ server.stat_aofrw_consecutive_failures = 0;
+
+ serverLog(LL_NOTICE, "Background AOF rewrite finished successfully");
+ /* Change state from WAIT_REWRITE to ON if needed */
+ if (server.aof_state == AOF_WAIT_REWRITE) {
+ server.aof_state = AOF_ON;
+
+ /* Update the fsynced replication offset that just now become valid.
+ * This could either be the one we took in startAppendOnly, or a
+ * newer one set by the bio thread. */
+ long long fsynced_reploff_pending;
+ atomicGet(server.fsynced_reploff_pending, fsynced_reploff_pending);
+ server.fsynced_reploff = fsynced_reploff_pending;
+ }
+
+ serverLog(LL_VERBOSE,
+ "Background AOF rewrite signal handler took %lldus", ustime()-now);
+ } else if (!bysignal && exitcode != 0) {
+ server.aof_lastbgrewrite_status = C_ERR;
+ server.stat_aofrw_consecutive_failures++;
+
+ serverLog(LL_WARNING,
+ "Background AOF rewrite terminated with error");
+ } else {
+ /* SIGUSR1 is whitelisted, so we have a way to kill a child without
+ * triggering an error condition. */
+ if (bysignal != SIGUSR1) {
+ server.aof_lastbgrewrite_status = C_ERR;
+ server.stat_aofrw_consecutive_failures++;
+ }
+
+ serverLog(LL_WARNING,
+ "Background AOF rewrite terminated by signal %d", bysignal);
+ }
+
+cleanup:
+ aofRemoveTempFile(server.child_pid);
+ /* Clear AOF buffer and delete temp incr aof for next rewrite. */
+ if (server.aof_state == AOF_WAIT_REWRITE) {
+ sdsfree(server.aof_buf);
+ server.aof_buf = sdsempty();
+ aofDelTempIncrAofFile();
+ }
+ server.aof_rewrite_time_last = time(NULL)-server.aof_rewrite_time_start;
+ server.aof_rewrite_time_start = -1;
+ /* Schedule a new rewrite if we are waiting for it to switch the AOF ON. */
+ if (server.aof_state == AOF_WAIT_REWRITE)
+ server.aof_rewrite_scheduled = 1;
+}