/*
* Copyright (c) 2009-2010, 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 "redis.h"
#ifdef HAVE_BACKTRACE
#include <execinfo.h>
#include <ucontext.h>
#endif /* HAVE_BACKTRACE */
#include <time.h>
#include <signal.h>
#include <sys/wait.h>
#include <errno.h>
#include <assert.h>
#include <ctype.h>
#include <stdarg.h>
#include <arpa/inet.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <sys/uio.h>
#include <limits.h>
#include <float.h>
#include <math.h>
#include <pthread.h>
#include <sys/resource.h>
/* Our shared "common" objects */
struct sharedObjectsStruct shared;
/* Global vars that are actally used as constants. The following double
* values are used for double on-disk serialization, and are initialized
* at runtime to avoid strange compiler optimizations. */
double R_Zero, R_PosInf, R_NegInf, R_Nan;
/*================================= Globals ================================= */
/* Global vars */
struct redisServer server; /* server global state */
struct redisCommand *commandTable;
struct redisCommand redisCommandTable[] = {
{"get",getCommand,2,0,NULL,1,1,1,0,0},
{"set",setCommand,3,REDIS_CMD_DENYOOM,noPreloadGetKeys,1,1,1,0,0},
{"setnx",setnxCommand,3,REDIS_CMD_DENYOOM,noPreloadGetKeys,1,1,1,0,0},
{"setex",setexCommand,4,REDIS_CMD_DENYOOM,noPreloadGetKeys,2,2,1,0,0},
{"append",appendCommand,3,REDIS_CMD_DENYOOM,NULL,1,1,1,0,0},
{"strlen",strlenCommand,2,0,NULL,1,1,1,0,0},
{"del",delCommand,-2,0,noPreloadGetKeys,1,-1,1,0,0},
{"exists",existsCommand,2,0,NULL,1,1,1,0,0},
{"setbit",setbitCommand,4,REDIS_CMD_DENYOOM,NULL,1,1,1,0,0},
{"getbit",getbitCommand,3,0,NULL,1,1,1,0,0},
{"setrange",setrangeCommand,4,REDIS_CMD_DENYOOM,NULL,1,1,1,0,0},
{"getrange",getrangeCommand,4,0,NULL,1,1,1,0,0},
{"substr",getrangeCommand,4,0,NULL,1,1,1,0,0},
{"incr",incrCommand,2,REDIS_CMD_DENYOOM,NULL,1,1,1,0,0},
{"decr",decrCommand,2,REDIS_CMD_DENYOOM,NULL,1,1,1,0,0},
{"mget",mgetCommand,-2,0,NULL,1,-1,1,0,0},
{"rpush",rpushCommand,3,REDIS_CMD_DENYOOM,NULL,1,1,1,0,0},
{"lpush",lpushCommand,3,REDIS_CMD_DENYOOM,NULL,1,1,1,0,0},
{"rpushx",rpushxCommand,3,REDIS_CMD_DENYOOM,NULL,1,1,1,0,0},
{"lpushx",lpushxCommand,3,REDIS_CMD_DENYOOM,NULL,1,1,1,0,0},
{"linsert",linsertCommand,5,REDIS_CMD_DENYOOM,NULL,1,1,1,0,0},
{"rpop",rpopCommand,2,0,NULL,1,1,1,0,0},
{"lpop",lpopCommand,2,0,NULL,1,1,1,0,0},
{"brpop",brpopCommand,-3,0,NULL,1,1,1,0,0},
{"brpoplpush",brpoplpushCommand,4,REDIS_CMD_DENYOOM,NULL,1,2,1,0,0},
{"blpop",blpopCommand,-3,0,NULL,1,-2,1,0,0},
{"llen",llenCommand,2,0,NULL,1,1,1,0,0},
{"lindex",lindexCommand,3,0,NULL,1,1,1,0,0},
{"lset",lsetCommand,4,REDIS_CMD_DENYOOM,NULL,1,1,1,0,0},
{"lrange",lrangeCommand,4,0,NULL,1,1,1,0,0},
{"ltrim",ltrimCommand,4,0,NULL,1,1,1,0,0},
{"lrem",lremCommand,4,0,NULL,1,1,1,0,0},
{"rpoplpush",rpoplpushCommand,3,REDIS_CMD_DENYOOM,NULL,1,2,1,0,0},
{"sadd",saddCommand,3,REDIS_CMD_DENYOOM,NULL,1,1,1,0,0},
{"srem",sremCommand,3,0,NULL,1,1,1,0,0},
{"smove",smoveCommand,4,0,NULL,1,2,1,0,0},
{"sismember",sismemberCommand,3,0,NULL,1,1,1,0,0},
{"scard",scardCommand,2,0,NULL,1,1,1,0,0},
{"spop",spopCommand,2,0,NULL,1,1,1,0,0},
{"srandmember",srandmemberCommand,2,0,NULL,1,1,1,0,0},
{"sinter",sinterCommand,-2,REDIS_CMD_DENYOOM,NULL,1,-1,1,0,0},
{"sinterstore",sinterstoreCommand,-3,REDIS_CMD_DENYOOM,NULL,2,-1,1,0,0},
{"sunion",sunionCommand,-2,REDIS_CMD_DENYOOM,NULL,1,-1,1,0,0},
{"sunionstore",sunionstoreCommand,-3,REDIS_CMD_DENYOOM,NULL,2,-1,1,0,0},
{"sdiff",sdiffCommand,-2,REDIS_CMD_DENYOOM,NULL,1,-1,1,0,0},
{"sdiffstore",sdiffstoreCommand,-3,REDIS_CMD_DENYOOM,NULL,2,-1,1,0,0},
{"smembers",sinterCommand,2,0,NULL,1,1,1,0,0},
{"zadd",zaddCommand,4,REDIS_CMD_DENYOOM,NULL,1,1,1,0,0},
{"zincrby",zincrbyCommand,4,REDIS_CMD_DENYOOM,NULL,1,1,1,0,0},
{"zrem",zremCommand,3,0,NULL,1,1,1,0,0},
{"zremrangebyscore",zremrangebyscoreCommand,4,0,NULL,1,1,1,0,0},
{"zremrangebyrank",zremrangebyrankCommand,4,0,NULL,1,1,1,0,0},
{"zunionstore",zunionstoreCommand,-4,REDIS_CMD_DENYOOM,zunionInterGetKeys,0,0,0,0,0},
{"zinterstore",zinterstoreCommand,-4,REDIS_CMD_DENYOOM,zunionInterGetKeys,0,0,0,0,0},
{"zrange",zrangeCommand,-4,0,NULL,1,1,1,0,0},
{"zrangebyscore",zrangebyscoreCommand,-4,0,NULL,1,1,1,0,0},
{"zrevrangebyscore",zrevrangebyscoreCommand,-4,0,NULL,1,1,1,0,0},
{"zcount",zcountCommand,4,0,NULL,1,1,1,0,0},
{"zrevrange",zrevrangeCommand,-4,0,NULL,1,1,1,0,0},
{"zcard",zcardCommand,2,0,NULL,1,1,1,0,0},
{"zscore",zscoreCommand,3,0,NULL,1,1,1,0,0},
{"zrank",zrankCommand,3,0,NULL,1,1,1,0,0},
{"zrevrank",zrevrankCommand,3,0,NULL,1,1,1,0,0},
{"hset",hsetCommand,4,REDIS_CMD_DENYOOM,NULL,1,1,1,0,0},
{"hsetnx",hsetnxCommand,4,REDIS_CMD_DENYOOM,NULL,1,1,1,0,0},
{"hget",hgetCommand,3,0,NULL,1,1,1,0,0},
{"hmset",hmsetCommand,-4,REDIS_CMD_DENYOOM,NULL,1,1,1,0,0},
{"hmget",hmgetCommand,-3,0,NULL,1,1,1,0,0},
{"hincrby",hincrbyCommand,4,REDIS_CMD_DENYOOM,NULL,1,1,1,0,0},
{"hdel",hdelCommand,3,0,NULL,1,1,1,0,0},
{"hlen",hlenCommand,2,0,NULL,1,1,1,0,0},
{"hkeys",hkeysCommand,2,0,NULL,1,1,1,0,0},
{"hvals",hvalsCommand,2,0,NULL,1,1,1,0,0},
{"hgetall",hgetallCommand,2,0,NULL,1,1,1,0,0},
{"hexists",hexistsCommand,3,0,NULL,1,1,1,0,0},
{"incrby",incrbyCommand,3,REDIS_CMD_DENYOOM,NULL,1,1,1,0,0},
{"decrby",decrbyCommand,3,REDIS_CMD_DENYOOM,NULL,1,1,1,0,0},
{"getset",getsetCommand,3,REDIS_CMD_DENYOOM,NULL,1,1,1,0,0},
{"mset",msetCommand,-3,REDIS_CMD_DENYOOM,NULL,1,-1,2,0,0},
{"msetnx",msetnxCommand,-3,REDIS_CMD_DENYOOM,NULL,1,-1,2,0,0},
{"randomkey",randomkeyCommand,1,0,NULL,0,0,0,0,0},
{"select",selectCommand,2,0,NULL,0,0,0,0,0},
{"move",moveCommand,3,0,NULL,1,1,1,0,0},
{"rename",renameCommand,3,0,renameGetKeys,1,2,1,0,0},
{"renamenx",renamenxCommand,3,0,renameGetKeys,1,2,1,0,0},
{"expire",expireCommand,3,0,NULL,1,1,1,0,0},
{"expireat",expireatCommand,3,0,NULL,1,1,1,0,0},
{"keys",keysCommand,2,0,NULL,0,0,0,0,0},
{"dbsize",dbsizeCommand,1,0,NULL,0,0,0,0,0},
{"auth",authCommand,2,0,NULL,0,0,0,0,0},
{"ping",pingCommand,1,0,NULL,0,0,0,0,0},
{"echo",echoCommand,2,0,NULL,0,0,0,0,0},
{"save",saveCommand,1,0,NULL,0,0,0,0,0},
{"bgsave",bgsaveCommand,1,0,NULL,0,0,0,0,0},
{"bgrewriteaof",bgrewriteaofCommand,1,0,NULL,0,0,0,0,0},
{"shutdown",shutdownCommand,1,0,NULL,0,0,0,0,0},
{"lastsave",lastsaveCommand,1,0,NULL,0,0,0,0,0},
{"type",typeCommand,2,0,NULL,1,1,1,0,0},
{"multi",multiCommand,1,0,NULL,0,0,0,0,0},
{"exec",execCommand,1,REDIS_CMD_DENYOOM,NULL,0,0,0,0,0},
{"discard",discardCommand,1,0,NULL,0,0,0,0,0},
{"sync",syncCommand,1,0,NULL,0,0,0,0,0},
{"flushdb",flushdbCommand,1,0,NULL,0,0,0,0,0},
{"flushall",flushallCommand,1,0,NULL,0,0,0,0,0},
{"sort",sortCommand,-2,REDIS_CMD_DENYOOM,NULL,1,1,1,0,0},
{"info",infoCommand,-1,0,NULL,0,0,0,0,0},
{"monitor",monitorCommand,1,0,NULL,0,0,0,0,0},
{"ttl",ttlCommand,2,0,NULL,1,1,1,0,0},
{"persist",persistCommand,2,0,NULL,1,1,1,0,0},
{"slaveof",slaveofCommand,3,0,NULL,0,0,0,0,0},
{"debug",debugCommand,-2,0,NULL,0,0,0,0,0},
{"config",configCommand,-2,0,NULL,0,0,0,0,0},
{"subscribe",subscribeCommand,-2,0,NULL,0,0,0,0,0},
{"unsubscribe",unsubscribeCommand,-1,0,NULL,0,0,0,0,0},
{"psubscribe",psubscribeCommand,-2,0,NULL,0,0,0,0,0},
{"punsubscribe",punsubscribeCommand,-1,0,NULL,0,0,0,0,0},
{"publish",publishCommand,3,REDIS_CMD_FORCE_REPLICATION,NULL,0,0,0,0,0},
{"watch",watchCommand,-2,0,noPreloadGetKeys,1,-1,1,0,0},
{"unwatch",unwatchCommand,1,0,NULL,0,0,0,0,0},
{"cluster",clusterCommand,-2,0,NULL,0,0,0,0,0},
{"restore",restoreCommand,3,0,NULL,0,0,0,0,0},
{"migrate",migrateCommand,6,0,NULL,0,0,0,0,0}
};
/*============================ Utility functions ============================ */
/* Low level logging. To use only for very big messages, otherwise
* redisLog() is to prefer. */
void redisLogRaw(int level, const char *msg) {
const int syslogLevelMap[] = { LOG_DEBUG, LOG_INFO, LOG_NOTICE, LOG_WARNING };
const char *c = ".-*#";
time_t now = time(NULL);
FILE *fp;
char buf[64];
if (level < server.verbosity) return;
fp = (server.logfile == NULL) ? stdout : fopen(server.logfile,"a");
if (!fp) return;
strftime(buf,sizeof(buf),"%d %b %H:%M:%S",localtime(&now));
fprintf(fp,"[%d] %s %c %s\n",(int)getpid(),buf,c[level],msg);
fflush(fp);
if (server.logfile) fclose(fp);
if (server.syslog_enabled) syslog(syslogLevelMap[level], "%s", msg);
}
/* Like redisLogRaw() but with printf-alike support. This is the funciton that
* is used across the code. The raw version is only used in order to dump
* the INFO output on crash. */
void redisLog(int level, const char *fmt, ...) {
va_list ap;
char msg[REDIS_MAX_LOGMSG_LEN];
if (level < server.verbosity) return;
va_start(ap, fmt);
vsnprintf(msg, sizeof(msg), fmt, ap);
va_end(ap);
redisLogRaw(level,msg);
}
/* Redis generally does not try to recover from out of memory conditions
* when allocating objects or strings, it is not clear if it will be possible
* to report this condition to the client since the networking layer itself
* is based on heap allocation for send buffers, so we simply abort.
* At least the code will be simpler to read... */
void oom(const char *msg) {
redisLog(REDIS_WARNING, "%s: Out of memory\n",msg);
sleep(1);
abort();
}
/* Return the UNIX time in microseconds */
long long ustime(void) {
struct timeval tv;
long long ust;
gettimeofday(&tv, NULL);
ust = ((long long)tv.tv_sec)*1000000;
ust += tv.tv_usec;
return ust;
}
/*====================== Hash table type implementation ==================== */
/* This is an hash table type that uses the SDS dynamic strings libary as
* keys and radis objects as values (objects can hold SDS strings,
* lists, sets). */
void dictVanillaFree(void *privdata, void *val)
{
DICT_NOTUSED(privdata);
zfree(val);
}
void dictListDestructor(void *privdata, void *val)
{
DICT_NOTUSED(privdata);
listRelease((list*)val);
}
int dictSdsKeyCompare(void *privdata, const void *key1,
const void *key2)
{
int l1,l2;
DICT_NOTUSED(privdata);
l1 = sdslen((sds)key1);
l2 = sdslen((sds)key2);
if (l1 != l2) return 0;
return memcmp(key1, key2, l1) == 0;
}
/* A case insensitive version used for the command lookup table. */
int dictSdsKeyCaseCompare(void *privdata, const void *key1,
const void *key2)
{
DICT_NOTUSED(privdata);
return strcasecmp(key1, key2) == 0;
}
void dictRedisObjectDestructor(void *privdata, void *val)
{
DICT_NOTUSED(privdata);
if (val == NULL) return; /* Values of swapped out keys as set to NULL */
decrRefCount(val);
}
void dictSdsDestructor(void *privdata, void *val)
{
DICT_NOTUSED(privdata);
sdsfree(val);
}
int dictObjKeyCompare(void *privdata, const void *key1,
const void *key2)
{
const robj *o1 = key1, *o2 = key2;
return dictSdsKeyCompare(privdata,o1->ptr,o2->ptr);
}
unsigned int dictObjHash(const void *key) {
const robj *o = key;
return dictGenHashFunction(o->ptr, sdslen((sds)o->ptr));
}
unsigned int dictSdsHash(const void *key) {
return dictGenHashFunction((unsigned char*)key, sdslen((char*)key));
}
unsigned int dictSdsCaseHash(const void *key) {
return dictGenCaseHashFunction((unsigned char*)key, sdslen((char*)key));
}
int dictEncObjKeyCompare(void *privdata, const void *key1,
const void *key2)
{
robj *o1 = (robj*) key1, *o2 = (robj*) key2;
int cmp;
if (o1->encoding == REDIS_ENCODING_INT &&
o2->encoding == REDIS_ENCODING_INT)
return o1->ptr == o2->ptr;
o1 = getDecodedObject(o1);
o2 = getDecodedObject(o2);
cmp = dictSdsKeyCompare(privdata,o1->ptr,o2->ptr);
decrRefCount(o1);
decrRefCount(o2);
return cmp;
}
unsigned int dictEncObjHash(const void *key) {
robj *o = (robj*) key;
if (o->encoding == REDIS_ENCODING_RAW) {
return dictGenHashFunction(o->ptr, sdslen((sds)o->ptr));
} else {
if (o->encoding == REDIS_ENCODING_INT) {
char buf[32];
int len;
len = ll2string(buf,32,(long)o->ptr);
return dictGenHashFunction((unsigned char*)buf, len);
} else {
unsigned int hash;
o = getDecodedObject(o);
hash = dictGenHashFunction(o->ptr, sdslen((sds)o->ptr));
decrRefCount(o);
return hash;
}
}
}
/* Sets type and diskstore negative caching hash table */
dictType setDictType = {
dictEncObjHash, /* hash function */
NULL, /* key dup */
NULL, /* val dup */
dictEncObjKeyCompare, /* key compare */
dictRedisObjectDestructor, /* key destructor */
NULL /* val destructor */
};
/* Sorted sets hash (note: a skiplist is used in addition to the hash table) */
dictType zsetDictType = {
dictEncObjHash, /* hash function */
NULL, /* key dup */
NULL, /* val dup */
dictEncObjKeyCompare, /* key compare */
dictRedisObjectDestructor, /* key destructor */
NULL /* val destructor */
};
/* Db->dict, keys are sds strings, vals are Redis objects. */
dictType dbDictType = {
dictSdsHash, /* hash function */
NULL, /* key dup */
NULL, /* val dup */
dictSdsKeyCompare, /* key compare */
dictSdsDestructor, /* key destructor */
dictRedisObjectDestructor /* val destructor */
};
/* Db->expires */
dictType keyptrDictType = {
dictSdsHash, /* hash function */
NULL, /* key dup */
NULL, /* val dup */
dictSdsKeyCompare, /* key compare */
NULL, /* key destructor */
NULL /* val destructor */
};
/* Command table. sds string -> command struct pointer. */
dictType commandTableDictType = {
dictSdsCaseHash, /* hash function */
NULL, /* key dup */
NULL, /* val dup */
dictSdsKeyCaseCompare, /* key compare */
dictSdsDestructor, /* key destructor */
NULL /* val destructor */
};
/* Hash type hash table (note that small hashes are represented with zimpaps) */
dictType hashDictType = {
dictEncObjHash, /* hash function */
NULL, /* key dup */
NULL, /* val dup */
dictEncObjKeyCompare, /* key compare */
dictRedisObjectDestructor, /* key destructor */
dictRedisObjectDestructor /* val destructor */
};
/* Keylist hash table type has unencoded redis objects as keys and
* lists as values. It's used for blocking operations (BLPOP) and to
* map swapped keys to a list of clients waiting for this keys to be loaded. */
dictType keylistDictType = {
dictObjHash, /* hash function */
NULL, /* key dup */
NULL, /* val dup */
dictObjKeyCompare, /* key compare */
dictRedisObjectDestructor, /* key destructor */
dictListDestructor /* val destructor */
};
/* Cluster nodes hash table, mapping nodes addresses 1.2.3.4:6379 to
* clusterNode structures. */
dictType clusterNodesDictType = {
dictSdsHash, /* hash function */
NULL, /* key dup */
NULL, /* val dup */
dictSdsKeyCompare, /* key compare */
dictSdsDestructor, /* key destructor */
NULL /* val destructor */
};
int htNeedsResize(dict *dict) {
long long size, used;
size = dictSlots(dict);
used = dictSize(dict);
return (size && used && size > DICT_HT_INITIAL_SIZE &&
(used*100/size < REDIS_HT_MINFILL));
}
/* If the percentage of used slots in the HT reaches REDIS_HT_MINFILL
* we resize the hash table to save memory */
void tryResizeHashTables(void) {
int j;
for (j = 0; j < server.dbnum; j++) {
if (htNeedsResize(server.db[j].dict))
dictResize(server.db[j].dict);
if (htNeedsResize(server.db[j].expires))
dictResize(server.db[j].expires);
}
}
/* Our hash table implementation performs rehashing incrementally while
* we write/read from the hash table. Still if the server is idle, the hash
* table will use two tables for a long time. So we try to use 1 millisecond
* of CPU time at every serverCron() loop in order to rehash some key. */
void incrementallyRehash(void) {
int j;
for (j = 0; j < server.dbnum; j++) {
if (dictIsRehashing(server.db[j].dict)) {
dictRehashMilliseconds(server.db[j].dict,1);
break; /* already used our millisecond for this loop... */
}
}
}
/* This function is called once a background process of some kind terminates,
* as we want to avoid resizing the hash tables when there is a child in order
* to play well with copy-on-write (otherwise when a resize happens lots of
* memory pages are copied). The goal of this function is to update the ability
* for dict.c to resize the hash tables accordingly to the fact we have o not
* running childs. */
void updateDictResizePolicy(void) {
if (server.bgsavechildpid == -1 && server.bgrewritechildpid == -1)
dictEnableResize();
else
dictDisableResize();
}
/* ======================= Cron: called every 100 ms ======================== */
/* Try to expire a few timed out keys. The algorithm used is adaptive and
* will use few CPU cycles if there are few expiring keys, otherwise
* it will get more aggressive to avoid that too much memory is used by
* keys that can be removed from the keyspace. */
void activeExpireCycle(void) {
int j;
for (j = 0; j < server.dbnum; j++) {
int expired;
redisDb *db = server.db+j;
/* Continue to expire if at the end of the cycle more than 25%
* of the keys were expired. */
do {
long num = dictSize(db->expires);
time_t now = time(NULL);
expired = 0;
if (num > REDIS_EXPIRELOOKUPS_PER_CRON)
num = REDIS_EXPIRELOOKUPS_PER_CRON;
while (num--) {
dictEntry *de;
time_t t;
if ((de = dictGetRandomKey(db->expires)) == NULL) break;
t = (time_t) dictGetEntryVal(de);
if (now > t) {
sds key = dictGetEntryKey(de);
robj *keyobj = createStringObject(key,sdslen(key));
propagateExpire(db,keyobj);
dbDelete(db,keyobj);
decrRefCount(keyobj);
expired++;
server.stat_expiredkeys++;
}
}
} while (expired > REDIS_EXPIRELOOKUPS_PER_CRON/4);
}
}
void updateLRUClock(void) {
server.lruclock = (time(NULL)/REDIS_LRU_CLOCK_RESOLUTION) &
REDIS_LRU_CLOCK_MAX;
}
int serverCron(struct aeEventLoop *eventLoop, long long id, void *clientData) {
int j, loops = server.cronloops;
REDIS_NOTUSED(eventLoop);
REDIS_NOTUSED(id);
REDIS_NOTUSED(clientData);
/* We take a cached value of the unix time in the global state because
* with virtual memory and aging there is to store the current time
* in objects at every object access, and accuracy is not needed.
* To access a global var is faster than calling time(NULL) */
server.unixtime = time(NULL);
/* We have just 22 bits per object for LRU information.
* So we use an (eventually wrapping) LRU clock with 10 seconds resolution.
* 2^22 bits with 10 seconds resoluton is more or less 1.5 years.
*
* Note that even if this will wrap after 1.5 years it's not a problem,
* everything will still work but just some object will appear younger
* to Redis. But for this to happen a given object should never be touched
* for 1.5 years.
*
* Note that you can change the resolution altering the
* REDIS_LRU_CLOCK_RESOLUTION define.
*/
updateLRUClock();
/* We received a SIGTERM, shutting down here in a safe way, as it is
* not ok doing so inside the signal handler. */
if (server.shutdown_asap) {
if (prepareForShutdown() == REDIS_OK) exit(0);
redisLog(REDIS_WARNING,"SIGTERM received but errors trying to shut down the server, check the logs for more information");
}
/* Show some info about non-empty databases */
for (j = 0; j < server.dbnum; j++) {
long long size, used, vkeys;
size = dictSlots(server.db[j].dict);
used = dictSize(server.db[j].dict);
vkeys = dictSize(server.db[j].expires);
if (!(loops % 50) && (used || vkeys)) {
redisLog(REDIS_VERBOSE,"DB %d: %lld keys (%lld volatile) in %lld slots HT.",j,used,vkeys,size);
/* dictPrintStats(server.dict); */
}
}
/* We don't want to resize the hash tables while a bacground saving
* is in progress: the saving child is created using fork() that is
* implemented with a copy-on-write semantic in most modern systems, so
* if we resize the HT while there is the saving child at work actually
* a lot of memory movements in the parent will cause a lot of pages
* copied. */
if (server.bgsavechildpid == -1 && server.bgrewritechildpid == -1) {
if (!(loops % 10)) tryResizeHashTables();
if (server.activerehashing) incrementallyRehash();
}
/* Show information about connected clients */
if (!(loops % 50)) {
redisLog(REDIS_VERBOSE,"%d clients connected (%d slaves), %zu bytes in use",
listLength(server.clients)-listLength(server.slaves),
listLength(server.slaves),
zmalloc_used_memory());
}
/* Close connections of timedout clients */
if ((server.maxidletime && !(loops % 100)) || server.bpop_blocked_clients)
closeTimedoutClients();
/* Check if a background saving or AOF rewrite in progress terminated. */
if (server.bgsavechildpid != -1 || server.bgrewritechildpid != -1) {
int statloc;
pid_t pid;
if ((pid = wait3(&statloc,WNOHANG,NULL)) != 0) {
int exitcode = WEXITSTATUS(statloc);
int bysignal = 0;
if (WIFSIGNALED(statloc)) bysignal = WTERMSIG(statloc);
if (pid == server.bgsavechildpid) {
backgroundSaveDoneHandler(exitcode,bysignal);
} else {
backgroundRewriteDoneHandler(exitcode,bysignal);
}
updateDictResizePolicy();
}
} else if (server.bgsavethread != (pthread_t) -1) {
if (server.bgsavethread != (pthread_t) -1) {
int state;
pthread_mutex_lock(&server.bgsavethread_mutex);
state = server.bgsavethread_state;
pthread_mutex_unlock(&server.bgsavethread_mutex);
if (state == REDIS_BGSAVE_THREAD_DONE_OK ||
state == REDIS_BGSAVE_THREAD_DONE_ERR)
{
backgroundSaveDoneHandler(
(state == REDIS_BGSAVE_THREAD_DONE_OK) ? 0 : 1, 0);
}
}
} else if (!server.ds_enabled) {
/* If there is not a background saving in progress check if
* we have to save now */
time_t now = time(NULL);
for (j = 0; j < server.saveparamslen; j++) {
struct saveparam *sp = server.saveparams+j;
if (server.dirty >= sp->changes &&
now-server.lastsave > sp->seconds) {
redisLog(REDIS_NOTICE,"%d changes in %d seconds. Saving...",
sp->changes, sp->seconds);
rdbSaveBackground(server.dbfilename);
break;
}
}
}
/* Expire a few keys per cycle, only if this is a master.
* On slaves we wait for DEL operations synthesized by the master
* in order to guarantee a strict consistency. */
if (server.masterhost == NULL) activeExpireCycle();
/* Remove a few cached objects from memory if we are over the
* configured memory limit */
if (server.ds_enabled) cacheCron();
/* Replication cron function -- used to reconnect to master and
* to detect transfer failures. */
if (!(loops % 10)) replicationCron();
/* Run other sub-systems specific cron jobs */
if (server.cluster_enabled && !(loops % 10)) clusterCron();
server.cronloops++;
return 100;
}
/* This function gets called every time Redis is entering the
* main loop of the event driven library, that is, before to sleep
* for ready file descriptors. */
void beforeSleep(struct aeEventLoop *eventLoop) {
REDIS_NOTUSED(eventLoop);
listNode *ln;
redisClient *c;
/* Awake clients that got all the on disk keys they requested */
if (server.ds_enabled && listLength(server.io_ready_clients)) {
listIter li;
listRewind(server.io_ready_clients,&li);
while((ln = listNext(&li))) {
c = ln->value;
struct redisCommand *cmd;
/* Resume the client. */
listDelNode(server.io_ready_clients,ln);
c->flags &= (~REDIS_IO_WAIT);
server.cache_blocked_clients--;
aeCreateFileEvent(server.el, c->fd, AE_READABLE,
readQueryFromClient, c);
cmd = lookupCommand(c->argv[0]->ptr);
redisAssert(cmd != NULL);
call(c,cmd);
resetClient(c);
/* There may be more data to process in the input buffer. */
if (c->querybuf && sdslen(c->querybuf) > 0)
processInputBuffer(c);
}
}
/* Try to process pending commands for clients that were just unblocked. */
while (listLength(server.unblocked_clients)) {
ln = listFirst(server.unblocked_clients);
redisAssert(ln != NULL);
c = ln->value;
listDelNode(server.unblocked_clients,ln);
c->flags &= ~REDIS_UNBLOCKED;
/* Process remaining data in the input buffer. */
if (c->querybuf && sdslen(c->querybuf) > 0)
processInputBuffer(c);
}
/* Write the AOF buffer on disk */
flushAppendOnlyFile();
}
/* =========================== Server initialization ======================== */
void createSharedObjects(void) {
int j;
shared.crlf = createObject(REDIS_STRING,sdsnew("\r\n"));
shared.ok = createObject(REDIS_STRING,sdsnew("+OK\r\n"));
shared.err = createObject(REDIS_STRING,sdsnew("-ERR\r\n"));
shared.emptybulk = createObject(REDIS_STRING,sdsnew("$0\r\n\r\n"));
shared.czero = createObject(REDIS_STRING,sdsnew(":0\r\n"));
shared.cone = createObject(REDIS_STRING,sdsnew(":1\r\n"));
shared.cnegone = createObject(REDIS_STRING,sdsnew(":-1\r\n"));
shared.nullbulk = createObject(REDIS_STRING,sdsnew("$-1\r\n"));
shared.nullmultibulk = createObject(REDIS_STRING,sdsnew("*-1\r\n"));
shared.emptymultibulk = createObject(REDIS_STRING,sdsnew("*0\r\n"));
shared.pong = createObject(REDIS_STRING,sdsnew("+PONG\r\n"));
shared.queued = createObject(REDIS_STRING,sdsnew("+QUEUED\r\n"));
shared.wrongtypeerr = createObject(REDIS_STRING,sdsnew(
"-ERR Operation against a key holding the wrong kind of value\r\n"));
shared.nokeyerr = createObject(REDIS_STRING,sdsnew(
"-ERR no such key\r\n"));
shared.syntaxerr = createObject(REDIS_STRING,sdsnew(
"-ERR syntax error\r\n"));
shared.sameobjecterr = createObject(REDIS_STRING,sdsnew(
"-ERR source and destination objects are the same\r\n"));
shared.outofrangeerr = createObject(REDIS_STRING,sdsnew(
"-ERR index out of range\r\n"));
shared.loadingerr = createObject(REDIS_STRING,sdsnew(
"-LOADING Redis is loading the dataset in memory\r\n"));
shared.space = createObject(REDIS_STRING,sdsnew(" "));
shared.colon = createObject(REDIS_STRING,sdsnew(":"));
shared.plus = createObject(REDIS_STRING,sdsnew("+"));
shared.select0 = createStringObject("select 0\r\n",10);
shared.select1 = createStringObject("select 1\r\n",10);
shared.select2 = createStringObject("select 2\r\n",10);
shared.select3 = createStringObject("select 3\r\n",10);
shared.select4 = createStringObject("select 4\r\n",10);
shared.select5 = createStringObject("select 5\r\n",10);
shared.select6 = createStringObject("select 6\r\n",10);
shared.select7 = createStringObject("select 7\r\n",10);
shared.select8 = createStringObject("select 8\r\n",10);
shared.select9 = createStringObject("select 9\r\n",10);
shared.messagebulk = createStringObject("$7\r\nmessage\r\n",13);
shared.pmessagebulk = createStringObject("$8\r\npmessage\r\n",14);
shared.subscribebulk = createStringObject("$9\r\nsubscribe\r\n",15);
shared.unsubscribebulk = createStringObject("$11\r\nunsubscribe\r\n",18);
shared.psubscribebulk = createStringObject("$10\r\npsubscribe\r\n",17);
shared.punsubscribebulk = createStringObject("$12\r\npunsubscribe\r\n",19);
shared.mbulk3 = createStringObject("*3\r\n",4);
shared.mbulk4 = createStringObject("*4\r\n",4);
for (j = 0; j < REDIS_SHARED_INTEGERS; j++) {
shared.integers[j] = createObject(REDIS_STRING,(void*)(long)j);
shared.integers[j]->encoding = REDIS_ENCODING_INT;
}
}
void initServerConfig() {
server.port = REDIS_SERVERPORT;
server.bindaddr = NULL;
server.unixsocket = NULL;
server.ipfd = -1;
server.sofd = -1;
server.dbnum = REDIS_DEFAULT_DBNUM;
server.verbosity = REDIS_VERBOSE;
server.maxidletime = REDIS_MAXIDLETIME;
server.saveparams = NULL;
server.loading = 0;
server.logfile = NULL; /* NULL = log on standard output */
server.syslog_enabled = 0;
server.syslog_ident = zstrdup("redis");
server.syslog_facility = LOG_LOCAL0;
server.daemonize = 0;
server.appendonly = 0;
server.appendfsync = APPENDFSYNC_EVERYSEC;
server.no_appendfsync_on_rewrite = 0;
server.lastfsync = time(NULL);
server.appendfd = -1;
server.appendseldb = -1; /* Make sure the first time will not match */
server.pidfile = zstrdup("/var/run/redis.pid");
server.dbfilename = zstrdup("dump.rdb");
server.appendfilename = zstrdup("appendonly.aof");
server.requirepass = NULL;
server.rdbcompression = 1;
server.activerehashing = 1;
server.maxclients = 0;
server.bpop_blocked_clients = 0;
server.maxmemory = 0;
server.maxmemory_policy = REDIS_MAXMEMORY_VOLATILE_LRU;
server.maxmemory_samples = 3;
server.ds_enabled = 0;
server.ds_path = sdsnew("/tmp/redis.ds");
server.cache_max_memory = 64LL*1024*1024; /* 64 MB of RAM */
server.cache_blocked_clients = 0;
server.hash_max_zipmap_entries = REDIS_HASH_MAX_ZIPMAP_ENTRIES;
server.hash_max_zipmap_value = REDIS_HASH_MAX_ZIPMAP_VALUE;
server.list_max_ziplist_entries = REDIS_LIST_MAX_ZIPLIST_ENTRIES;
server.list_max_ziplist_value = REDIS_LIST_MAX_ZIPLIST_VALUE;
server.set_max_intset_entries = REDIS_SET_MAX_INTSET_ENTRIES;
server.shutdown_asap = 0;
server.cache_flush_delay = 0;
server.cluster_enabled = 0;
updateLRUClock();
resetServerSaveParams();
appendServerSaveParams(60*60,1); /* save after 1 hour and 1 change */
appendServerSaveParams(300,100); /* save after 5 minutes and 100 changes */
appendServerSaveParams(60,10000); /* save after 1 minute and 10000 changes */
/* Replication related */
server.isslave = 0;
server.masterauth = NULL;
server.masterhost = NULL;
server.masterport = 6379;
server.master = NULL;
server.replstate = REDIS_REPL_NONE;
server.repl_serve_stale_data = 1;
/* Double constants initialization */
R_Zero = 0.0;
R_PosInf = 1.0/R_Zero;
R_NegInf = -1.0/R_Zero;
R_Nan = R_Zero/R_Zero;
/* Command table -- we intiialize it here as it is part of the
* initial configuration, since command names may be changed via
* redis.conf using the rename-command directive. */
server.commands = dictCreate(&commandTableDictType,NULL);
populateCommandTable();
server.delCommand = lookupCommandByCString("del");
server.multiCommand = lookupCommandByCString("multi");
}
void initServer() {
int j;
signal(SIGHUP, SIG_IGN);
signal(SIGPIPE, SIG_IGN);
setupSignalHandlers();
if (server.syslog_enabled) {
openlog(server.syslog_ident, LOG_PID | LOG_NDELAY | LOG_NOWAIT,
server.syslog_facility);
}
server.mainthread = pthread_self();
server.clients = listCreate();
server.slaves = listCreate();
server.monitors = listCreate();
server.unblocked_clients = listCreate();
server.cache_io_queue = listCreate();
createSharedObjects();
server.el = aeCreateEventLoop();
server.db = zmalloc(sizeof(redisDb)*server.dbnum);
if (server.port != 0) {
server.ipfd = anetTcpServer(server.neterr,server.port,server.bindaddr);
if (server.ipfd == ANET_ERR) {
redisLog(REDIS_WARNING, "Opening port: %s", server.neterr);
exit(1);
}
}
if (server.unixsocket != NULL) {
unlink(server.unixsocket); /* don't care if this fails */
server.sofd = anetUnixServer(server.neterr,server.unixsocket);
if (server.sofd == ANET_ERR) {
redisLog(REDIS_WARNING, "Opening socket: %s", server.neterr);
exit(1);
}
}
if (server.ipfd < 0 && server.sofd < 0) {
redisLog(REDIS_WARNING, "Configured to not listen anywhere, exiting.");
exit(1);
}
for (j = 0; j < server.dbnum; j++) {
server.db[j].dict = dictCreate(&dbDictType,NULL);
server.db[j].expires = dictCreate(&keyptrDictType,NULL);
server.db[j].blocking_keys = dictCreate(&keylistDictType,NULL);
server.db[j].watched_keys = dictCreate(&keylistDictType,NULL);
if (server.ds_enabled) {
server.db[j].io_keys = dictCreate(&keylistDictType,NULL);
server.db[j].io_negcache = dictCreate(&setDictType,NULL);
server.db[j].io_queued = dictCreate(&setDictType,NULL);
}
server.db[j].id = j;
}
server.pubsub_channels = dictCreate(&keylistDictType,NULL);
server.pubsub_patterns = listCreate();
listSetFreeMethod(server.pubsub_patterns,freePubsubPattern);
listSetMatchMethod(server.pubsub_patterns,listMatchPubsubPattern);
server.cronloops = 0;
server.bgsavechildpid = -1;
server.bgrewritechildpid = -1;
server.bgsavethread_state = REDIS_BGSAVE_THREAD_UNACTIVE;
server.bgsavethread = (pthread_t) -1;
server.bgrewritebuf = sdsempty();
server.aofbuf = sdsempty();
server.lastsave = time(NULL);
server.dirty = 0;
server.stat_numcommands = 0;
server.stat_numconnections = 0;
server.stat_expiredkeys = 0;
server.stat_evictedkeys = 0;
server.stat_starttime = time(NULL);
server.stat_keyspace_misses = 0;
server.stat_keyspace_hits = 0;
server.unixtime = time(NULL);
aeCreateTimeEvent(server.el, 1, serverCron, NULL, NULL);
if (server.ipfd > 0 && aeCreateFileEvent(server.el,server.ipfd,AE_READABLE,
acceptTcpHandler,NULL) == AE_ERR) oom("creating file event");
if (server.sofd > 0 && aeCreateFileEvent(server.el,server.sofd,AE_READABLE,
acceptUnixHandler,NULL) == AE_ERR) oom("creating file event");
if (server.appendonly) {
server.appendfd = open(server.appendfilename,O_WRONLY|O_APPEND|O_CREAT,0644);
if (server.appendfd == -1) {
redisLog(REDIS_WARNING, "Can't open the append-only file: %s",
strerror(errno));
exit(1);
}
}
if (server.ds_enabled) dsInit();
if (server.cluster_enabled) clusterInit();
srand(time(NULL)^getpid());
}
/* Populates the Redis Command Table starting from the hard coded list
* we have on top of redis.c file. */
void populateCommandTable(void) {
int j;
int numcommands = sizeof(redisCommandTable)/sizeof(struct redisCommand);
for (j = 0; j < numcommands; j++) {
struct redisCommand *c = redisCommandTable+j;
int retval;
retval = dictAdd(server.commands, sdsnew(c->name), c);
assert(retval == DICT_OK);
}
}
void resetCommandTableStats(void) {
int numcommands = sizeof(redisCommandTable)/sizeof(struct redisCommand);
int j;
for (j = 0; j < numcommands; j++) {
struct redisCommand *c = redisCommandTable+j;
c->microseconds = 0;
c->calls = 0;
}
}
/* ====================== Commands lookup and execution ===================== */
struct redisCommand *lookupCommand(sds name) {
return dictFetchValue(server.commands, name);
}
struct redisCommand *lookupCommandByCString(char *s) {
struct redisCommand *cmd;
sds name = sdsnew(s);
cmd = dictFetchValue(server.commands, name);
sdsfree(name);
return cmd;
}
/* Call() is the core of Redis execution of a command */
void call(redisClient *c, struct redisCommand *cmd) {
long long dirty, start = ustime();
dirty = server.dirty;
cmd->proc(c);
dirty = server.dirty-dirty;
cmd->microseconds += ustime()-start;
cmd->calls++;
if (server.appendonly && dirty)
feedAppendOnlyFile(cmd,c->db->id,c->argv,c->argc);
if ((dirty || cmd->flags & REDIS_CMD_FORCE_REPLICATION) &&
listLength(server.slaves))
replicationFeedSlaves(server.slaves,c->db->id,c->argv,c->argc);
if (listLength(server.monitors))
replicationFeedMonitors(server.monitors,c->db->id,c->argv,c->argc);
server.stat_numcommands++;
}
/* If this function gets called we already read a whole
* command, argments are in the client argv/argc fields.
* processCommand() execute the command or prepare the
* server for a bulk read from the client.
*
* If 1 is returned the client is still alive and valid and
* and other operations can be performed by the caller. Otherwise
* if 0 is returned the client was destroied (i.e. after QUIT). */
int processCommand(redisClient *c) {
struct redisCommand *cmd;
/* The QUIT command is handled separately. Normal command procs will
* go through checking for replication and QUIT will cause trouble
* when FORCE_REPLICATION is enabled and would be implemented in
* a regular command proc. */
if (!strcasecmp(c->argv[0]->ptr,"quit")) {
addReply(c,shared.ok);
c->flags |= REDIS_CLOSE_AFTER_REPLY;
return REDIS_ERR;
}
/* Now lookup the command and check ASAP about trivial error conditions
* such wrong arity, bad command name and so forth. */
cmd = lookupCommand(c->argv[0]->ptr);
if (!cmd) {
addReplyErrorFormat(c,"unknown command '%s'",
(char*)c->argv[0]->ptr);
return REDIS_OK;
} else if ((cmd->arity > 0 && cmd->arity != c->argc) ||
(c->argc < -cmd->arity)) {
addReplyErrorFormat(c,"wrong number of arguments for '%s' command",
cmd->name);
return REDIS_OK;
}
/* Check if the user is authenticated */
if (server.requirepass && !c->authenticated && cmd->proc != authCommand) {
addReplyError(c,"operation not permitted");
return REDIS_OK;
}
/* If cluster is enabled, redirect here */
if (server.cluster_enabled &&
!(cmd->getkeys_proc == NULL && cmd->firstkey == 0)) {
int hashslot;
if (server.cluster.state != REDIS_CLUSTER_OK) {
addReplyError(c,"The cluster is down. Check with CLUSTER INFO for more information");
return REDIS_OK;
} else {
clusterNode *n = getNodeByQuery(c,cmd,c->argv,c->argc,&hashslot);
if (n == NULL) {
addReplyError(c,"Invalid cross-node request");
return REDIS_OK;
} else if (n != server.cluster.myself) {
addReplySds(c,sdscatprintf(sdsempty(),
"-MOVED %d %s:%d\r\n",hashslot,n->ip,n->port));
return REDIS_OK;
}
}
}
/* Handle the maxmemory directive.
*
* First we try to free some memory if possible (if there are volatile
* keys in the dataset). If there are not the only thing we can do
* is returning an error. */
if (server.maxmemory) freeMemoryIfNeeded();
if (server.maxmemory && (cmd->flags & REDIS_CMD_DENYOOM) &&
zmalloc_used_memory() > server.maxmemory)
{
addReplyError(c,"command not allowed when used memory > 'maxmemory'");
return REDIS_OK;
}
/* Only allow SUBSCRIBE and UNSUBSCRIBE in the context of Pub/Sub */
if ((dictSize(c->pubsub_channels) > 0 || listLength(c->pubsub_patterns) > 0)
&&
cmd->proc != subscribeCommand && cmd->proc != unsubscribeCommand &&
cmd->proc != psubscribeCommand && cmd->proc != punsubscribeCommand) {
addReplyError(c,"only (P)SUBSCRIBE / (P)UNSUBSCRIBE / QUIT allowed in this context");
return REDIS_OK;
}
/* Only allow INFO and SLAVEOF when slave-serve-stale-data is no and
* we are a slave with a broken link with master. */
if (server.masterhost && server.replstate != REDIS_REPL_CONNECTED &&
server.repl_serve_stale_data == 0 &&
cmd->proc != infoCommand && cmd->proc != slaveofCommand)
{
addReplyError(c,
"link with MASTER is down and slave-serve-stale-data is set to no");
return REDIS_OK;
}
/* Loading DB? Return an error if the command is not INFO */
if (server.loading && cmd->proc != infoCommand) {
addReply(c, shared.loadingerr);
return REDIS_OK;
}
/* Exec the command */
if (c->flags & REDIS_MULTI &&
cmd->proc != execCommand && cmd->proc != discardCommand &&
cmd->proc != multiCommand && cmd->proc != watchCommand)
{
queueMultiCommand(c,cmd);
addReply(c,shared.queued);
} else {
if (server.ds_enabled && blockClientOnSwappedKeys(c,cmd))
return REDIS_ERR;
call(c,cmd);
}
return REDIS_OK;
}
/*================================== Shutdown =============================== */
int prepareForShutdown() {
redisLog(REDIS_WARNING,"User requested shutdown, saving DB...");
/* Kill the saving child if there is a background saving in progress.
We want to avoid race conditions, for instance our saving child may
overwrite the synchronous saving did by SHUTDOWN. */
if (server.bgsavechildpid != -1) {
redisLog(REDIS_WARNING,"There is a live saving child. Killing it!");
kill(server.bgsavechildpid,SIGKILL);
rdbRemoveTempFile(server.bgsavechildpid);
}
if (server.ds_enabled) {
/* FIXME: flush all objects on disk */
} else if (server.appendonly) {
/* Append only file: fsync() the AOF and exit */
aof_fsync(server.appendfd);
} else if (server.saveparamslen > 0) {
/* Snapshotting. Perform a SYNC SAVE and exit */
if (rdbSave(server.dbfilename) != REDIS_OK) {
/* Ooops.. error saving! The best we can do is to continue
* operating. Note that if there was a background saving process,
* in the next cron() Redis will be notified that the background
* saving aborted, handling special stuff like slaves pending for
* synchronization... */
redisLog(REDIS_WARNING,"Error trying to save the DB, can't exit");
return REDIS_ERR;
}
} else {
redisLog(REDIS_WARNING,"Not saving DB.");
}
if (server.daemonize) unlink(server.pidfile);
redisLog(REDIS_WARNING,"Server exit now, bye bye...");
return REDIS_OK;
}
/*================================== Commands =============================== */
void authCommand(redisClient *c) {
if (!server.requirepass || !strcmp(c->argv[1]->ptr, server.requirepass)) {
c->authenticated = 1;
addReply(c,shared.ok);
} else {
c->authenticated = 0;
addReplyError(c,"invalid password");
}
}
void pingCommand(redisClient *c) {
addReply(c,shared.pong);
}
void echoCommand(redisClient *c) {
addReplyBulk(c,c->argv[1]);
}
/* Convert an amount of bytes into a human readable string in the form
* of 100B, 2G, 100M, 4K, and so forth. */
void bytesToHuman(char *s, unsigned long long n) {
double d;
if (n < 1024) {
/* Bytes */
sprintf(s,"%lluB",n);
return;
} else if (n < (1024*1024)) {
d = (double)n/(1024);
sprintf(s,"%.2fK",d);
} else if (n < (1024LL*1024*1024)) {
d = (double)n/(1024*1024);
sprintf(s,"%.2fM",d);
} else if (n < (1024LL*1024*1024*1024)) {
d = (double)n/(1024LL*1024*1024);
sprintf(s,"%.2fG",d);
}
}
/* Create the string returned by the INFO command. This is decoupled
* by the INFO command itself as we need to report the same information
* on memory corruption problems. */
sds genRedisInfoString(char *section) {
sds info = sdsempty();
time_t uptime = time(NULL)-server.stat_starttime;
int j, numcommands;
char hmem[64];
struct rusage self_ru, c_ru;
unsigned long lol, bib;
int allsections = 0, defsections = 0;
int sections = 0;
if (section) {
allsections = strcasecmp(section,"all") == 0;
defsections = strcasecmp(section,"default") == 0;
}
getrusage(RUSAGE_SELF, &self_ru);
getrusage(RUSAGE_CHILDREN, &c_ru);
getClientsMaxBuffers(&lol,&bib);
bytesToHuman(hmem,zmalloc_used_memory());
/* Server */
if (allsections || defsections || !strcasecmp(section,"server")) {
if (sections++) info = sdscat(info,"\r\n");
info = sdscatprintf(info,
"# Server\r\n"
"redis_version:%s\r\n"
"redis_git_sha1:%s\r\n"
"redis_git_dirty:%d\r\n"
"arch_bits:%s\r\n"
"multiplexing_api:%s\r\n"
"process_id:%ld\r\n"
"tcp_port:%d\r\n"
"uptime_in_seconds:%ld\r\n"
"uptime_in_days:%ld\r\n"
"lru_clock:%ld\r\n",
REDIS_VERSION,
redisGitSHA1(),
strtol(redisGitDirty(),NULL,10) > 0,
(sizeof(long) == 8) ? "64" : "32",
aeGetApiName(),
(long) getpid(),
server.port,
uptime,
uptime/(3600*24),
(unsigned long) server.lruclock);
}
/* Clients */
if (allsections || defsections || !strcasecmp(section,"clients")) {
if (sections++) info = sdscat(info,"\r\n");
info = sdscatprintf(info,
"# Clients\r\n"
"connected_clients:%d\r\n"
"client_longest_output_list:%lu\r\n"
"client_biggest_input_buf:%lu\r\n"
"blocked_clients:%d\r\n",
listLength(server.clients)-listLength(server.slaves),
lol, bib,
server.bpop_blocked_clients);
}
/* Memory */
if (allsections || defsections || !strcasecmp(section,"memory")) {
if (sections++) info = sdscat(info,"\r\n");
info = sdscatprintf(info,
"# Memory\r\n"
"used_memory:%zu\r\n"
"used_memory_human:%s\r\n"
"used_memory_rss:%zu\r\n"
"mem_fragmentation_ratio:%.2f\r\n"
"use_tcmalloc:%d\r\n",
zmalloc_used_memory(),
hmem,
zmalloc_get_rss(),
zmalloc_get_fragmentation_ratio(),
#ifdef USE_TCMALLOC
1
#else
0
#endif
);
}
/* Allocation statistics */
if (allsections || !strcasecmp(section,"allocstats")) {
if (sections++) info = sdscat(info,"\r\n");
info = sdscat(info, "# Allocstats\r\nallocation_stats:");
for (j = 0; j <= ZMALLOC_MAX_ALLOC_STAT; j++) {
size_t count = zmalloc_allocations_for_size(j);
if (count) {
if (info[sdslen(info)-1] != ':') info = sdscatlen(info,",",1);
info = sdscatprintf(info,"%s%d=%zu",
(j == ZMALLOC_MAX_ALLOC_STAT) ? ">=" : "",
j,count);
}
}
info = sdscat(info,"\r\n");
}
/* Persistence */
if (allsections || defsections || !strcasecmp(section,"persistence")) {
if (sections++) info = sdscat(info,"\r\n");
info = sdscatprintf(info,
"# Persistence\r\n"
"loading:%d\r\n"
"aof_enabled:%d\r\n"
"changes_since_last_save:%lld\r\n"
"bgsave_in_progress:%d\r\n"
"last_save_time:%ld\r\n"
"bgrewriteaof_in_progress:%d\r\n",
server.loading,
server.appendonly,
server.dirty,
server.bgsavechildpid != -1 ||
server.bgsavethread != (pthread_t) -1,
server.lastsave,
server.bgrewritechildpid != -1);
if (server.loading) {
double perc;
time_t eta, elapsed;
off_t remaining_bytes = server.loading_total_bytes-
server.loading_loaded_bytes;
perc = ((double)server.loading_loaded_bytes /
server.loading_total_bytes) * 100;
elapsed = time(NULL)-server.loading_start_time;
if (elapsed == 0) {
eta = 1; /* A fake 1 second figure if we don't have
enough info */
} else {
eta = (elapsed*remaining_bytes)/server.loading_loaded_bytes;
}
info = sdscatprintf(info,
"loading_start_time:%ld\r\n"
"loading_total_bytes:%llu\r\n"
"loading_loaded_bytes:%llu\r\n"
"loading_loaded_perc:%.2f\r\n"
"loading_eta_seconds:%ld\r\n"
,(unsigned long) server.loading_start_time,
(unsigned long long) server.loading_total_bytes,
(unsigned long long) server.loading_loaded_bytes,
perc,
eta
);
}
}
/* Diskstore */
if (allsections || defsections || !strcasecmp(section,"diskstore")) {
if (sections++) info = sdscat(info,"\r\n");
info = sdscatprintf(info,
"# Diskstore\r\n"
"ds_enabled:%d\r\n",
server.ds_enabled != 0);
if (server.ds_enabled) {
lockThreadedIO();
info = sdscatprintf(info,
"cache_max_memory:%llu\r\n"
"cache_blocked_clients:%lu\r\n"
"cache_io_queue_len:%lu\r\n"
"cache_io_jobs_new:%lu\r\n"
"cache_io_jobs_processing:%lu\r\n"
"cache_io_jobs_processed:%lu\r\n"
"cache_io_ready_clients:%lu\r\n"
,(unsigned long long) server.cache_max_memory,
(unsigned long) server.cache_blocked_clients,
(unsigned long) listLength(server.cache_io_queue),
(unsigned long) listLength(server.io_newjobs),
(unsigned long) listLength(server.io_processing),
(unsigned long) listLength(server.io_processed),
(unsigned long) listLength(server.io_ready_clients)
);
unlockThreadedIO();
}
}
/* Stats */
if (allsections || defsections || !strcasecmp(section,"stats")) {
if (sections++) info = sdscat(info,"\r\n");
info = sdscatprintf(info,
"# Stats\r\n"
"total_connections_received:%lld\r\n"
"total_commands_processed:%lld\r\n"
"expired_keys:%lld\r\n"
"evicted_keys:%lld\r\n"
"keyspace_hits:%lld\r\n"
"keyspace_misses:%lld\r\n"
"pubsub_channels:%ld\r\n"
"pubsub_patterns:%u\r\n",
server.stat_numconnections,
server.stat_numcommands,
server.stat_expiredkeys,
server.stat_evictedkeys,
server.stat_keyspace_hits,
server.stat_keyspace_misses,
dictSize(server.pubsub_channels),
listLength(server.pubsub_patterns));
}
/* Replication */
if (allsections || defsections || !strcasecmp(section,"replication")) {
if (sections++) info = sdscat(info,"\r\n");
info = sdscatprintf(info,
"# Replication\r\n"
"role:%s\r\n",
server.masterhost == NULL ? "master" : "slave");
if (server.masterhost) {
info = sdscatprintf(info,
"master_host:%s\r\n"
"master_port:%d\r\n"
"master_link_status:%s\r\n"
"master_last_io_seconds_ago:%d\r\n"
"master_sync_in_progress:%d\r\n"
,server.masterhost,
server.masterport,
(server.replstate == REDIS_REPL_CONNECTED) ?
"up" : "down",
server.master ?
((int)(time(NULL)-server.master->lastinteraction)) : -1,
server.replstate == REDIS_REPL_TRANSFER
);
if (server.replstate == REDIS_REPL_TRANSFER) {
info = sdscatprintf(info,
"master_sync_left_bytes:%ld\r\n"
"master_sync_last_io_seconds_ago:%d\r\n"
,(long)server.repl_transfer_left,
(int)(time(NULL)-server.repl_transfer_lastio)
);
}
}
info = sdscatprintf(info,
"connected_slaves:%d\r\n",
listLength(server.slaves));
}
/* CPU */
if (allsections || defsections || !strcasecmp(section,"cpu")) {
if (sections++) info = sdscat(info,"\r\n");
info = sdscatprintf(info,
"# CPU\r\n"
"used_cpu_sys:%.2f\r\n"
"used_cpu_user:%.2f\r\n"
"used_cpu_sys_childrens:%.2f\r\n"
"used_cpu_user_childrens:%.2f\r\n",
(float)self_ru.ru_utime.tv_sec+(float)self_ru.ru_utime.tv_usec/1000000,
(float)self_ru.ru_stime.tv_sec+(float)self_ru.ru_stime.tv_usec/1000000,
(float)c_ru.ru_utime.tv_sec+(float)c_ru.ru_utime.tv_usec/1000000,
(float)c_ru.ru_stime.tv_sec+(float)c_ru.ru_stime.tv_usec/1000000);
}
/* cmdtime */
if (allsections || !strcasecmp(section,"commandstats")) {
if (sections++) info = sdscat(info,"\r\n");
info = sdscatprintf(info, "# Commandstats\r\n");
numcommands = sizeof(redisCommandTable)/sizeof(struct redisCommand);
for (j = 0; j < numcommands; j++) {
struct redisCommand *c = redisCommandTable+j;
if (!c->calls) continue;
info = sdscatprintf(info,
"cmdstat_%s:calls=%lld,usec=%lld,usec_per_call=%.2f\r\n",
c->name, c->calls, c->microseconds,
(c->calls == 0) ? 0 : ((float)c->microseconds/c->calls));
}
}
/* Key space */
if (allsections || defsections || !strcasecmp(section,"keyspace")) {
if (sections++) info = sdscat(info,"\r\n");
info = sdscatprintf(info, "# Keyspace\r\n");
for (j = 0; j < server.dbnum; j++) {
long long keys, vkeys;
keys = dictSize(server.db[j].dict);
vkeys = dictSize(server.db[j].expires);
if (keys || vkeys) {
info = sdscatprintf(info, "db%d:keys=%lld,expires=%lld\r\n",
j, keys, vkeys);
}
}
}
return info;
}
void infoCommand(redisClient *c) {
char *section = c->argc == 2 ? c->argv[1]->ptr : "default";
if (c->argc > 2) {
addReply(c,shared.syntaxerr);
return;
}
sds info = genRedisInfoString(section);
addReplySds(c,sdscatprintf(sdsempty(),"$%lu\r\n",
(unsigned long)sdslen(info)));
addReplySds(c,info);
addReply(c,shared.crlf);
}
void monitorCommand(redisClient *c) {
/* ignore MONITOR if aleady slave or in monitor mode */
if (c->flags & REDIS_SLAVE) return;
c->flags |= (REDIS_SLAVE|REDIS_MONITOR);
c->slaveseldb = 0;
listAddNodeTail(server.monitors,c);
addReply(c,shared.ok);
}
/* ============================ Maxmemory directive ======================== */
/* This function gets called when 'maxmemory' is set on the config file to limit
* the max memory used by the server, and we are out of memory.
* This function will try to, in order:
*
* - Free objects from the free list
* - Try to remove keys with an EXPIRE set
*
* It is not possible to free enough memory to reach used-memory < maxmemory
* the server will start refusing commands that will enlarge even more the
* memory usage.
*/
void freeMemoryIfNeeded(void) {
/* Remove keys accordingly to the active policy as long as we are
* over the memory limit. */
if (server.maxmemory_policy == REDIS_MAXMEMORY_NO_EVICTION) return;
while (server.maxmemory && zmalloc_used_memory() > server.maxmemory) {
int j, k, freed = 0;
for (j = 0; j < server.dbnum; j++) {
long bestval = 0; /* just to prevent warning */
sds bestkey = NULL;
struct dictEntry *de;
redisDb *db = server.db+j;
dict *dict;
if (server.maxmemory_policy == REDIS_MAXMEMORY_ALLKEYS_LRU ||
server.maxmemory_policy == REDIS_MAXMEMORY_ALLKEYS_RANDOM)
{
dict = server.db[j].dict;
} else {
dict = server.db[j].expires;
}
if (dictSize(dict) == 0) continue;
/* volatile-random and allkeys-random policy */
if (server.maxmemory_policy == REDIS_MAXMEMORY_ALLKEYS_RANDOM ||
server.maxmemory_policy == REDIS_MAXMEMORY_VOLATILE_RANDOM)
{
de = dictGetRandomKey(dict);
bestkey = dictGetEntryKey(de);
}
/* volatile-lru and allkeys-lru policy */
else if (server.maxmemory_policy == REDIS_MAXMEMORY_ALLKEYS_LRU ||
server.maxmemory_policy == REDIS_MAXMEMORY_VOLATILE_LRU)
{
for (k = 0; k < server.maxmemory_samples; k++) {
sds thiskey;
long thisval;
robj *o;
de = dictGetRandomKey(dict);
thiskey = dictGetEntryKey(de);
/* When policy is volatile-lru we need an additonal lookup
* to locate the real key, as dict is set to db->expires. */
if (server.maxmemory_policy == REDIS_MAXMEMORY_VOLATILE_LRU)
de = dictFind(db->dict, thiskey);
o = dictGetEntryVal(de);
thisval = estimateObjectIdleTime(o);
/* Higher idle time is better candidate for deletion */
if (bestkey == NULL || thisval > bestval) {
bestkey = thiskey;
bestval = thisval;
}
}
}
/* volatile-ttl */
else if (server.maxmemory_policy == REDIS_MAXMEMORY_VOLATILE_TTL) {
for (k = 0; k < server.maxmemory_samples; k++) {
sds thiskey;
long thisval;
de = dictGetRandomKey(dict);
thiskey = dictGetEntryKey(de);
thisval = (long) dictGetEntryVal(de);
/* Expire sooner (minor expire unix timestamp) is better
* candidate for deletion */
if (bestkey == NULL || thisval < bestval) {
bestkey = thiskey;
bestval = thisval;
}
}
}
/* Finally remove the selected key. */
if (bestkey) {
robj *keyobj = createStringObject(bestkey,sdslen(bestkey));
propagateExpire(db,keyobj);
dbDelete(db,keyobj);
server.stat_evictedkeys++;
decrRefCount(keyobj);
freed++;
}
}
if (!freed) return; /* nothing to free... */
}
}
/* =================================== Main! ================================ */
#ifdef __linux__
int linuxOvercommitMemoryValue(void) {
FILE *fp = fopen("/proc/sys/vm/overcommit_memory","r");
char buf[64];
if (!fp) return -1;
if (fgets(buf,64,fp) == NULL) {
fclose(fp);
return -1;
}
fclose(fp);
return atoi(buf);
}
void linuxOvercommitMemoryWarning(void) {
if (linuxOvercommitMemoryValue() == 0) {
redisLog(REDIS_WARNING,"WARNING overcommit_memory is set to 0! Background save may fail under low memory condition. To fix this issue add 'vm.overcommit_memory = 1' to /etc/sysctl.conf and then reboot or run the command 'sysctl vm.overcommit_memory=1' for this to take effect.");
}
}
#endif /* __linux__ */
void createPidFile(void) {
/* Try to write the pid file in a best-effort way. */
FILE *fp = fopen(server.pidfile,"w");
if (fp) {
fprintf(fp,"%d\n",(int)getpid());
fclose(fp);
}
}
void daemonize(void) {
int fd;
if (fork() != 0) exit(0); /* parent exits */
setsid(); /* create a new session */
/* Every output goes to /dev/null. If Redis is daemonized but
* the 'logfile' is set to 'stdout' in the configuration file
* it will not log at all. */
if ((fd = open("/dev/null", O_RDWR, 0)) != -1) {
dup2(fd, STDIN_FILENO);
dup2(fd, STDOUT_FILENO);
dup2(fd, STDERR_FILENO);
if (fd > STDERR_FILENO) close(fd);
}
}
void version() {
printf("Redis server version %s (%s:%d)\n", REDIS_VERSION,
redisGitSHA1(), atoi(redisGitDirty()) > 0);
exit(0);
}
void usage() {
fprintf(stderr,"Usage: ./redis-server [/path/to/redis.conf]\n");
fprintf(stderr," ./redis-server - (read config from stdin)\n");
exit(1);
}
int main(int argc, char **argv) {
long long start;
initServerConfig();
if (argc == 2) {
if (strcmp(argv[1], "-v") == 0 ||
strcmp(argv[1], "--version") == 0) version();
if (strcmp(argv[1], "--help") == 0) usage();
resetServerSaveParams();
loadServerConfig(argv[1]);
} else if ((argc > 2)) {
usage();
} else {
redisLog(REDIS_WARNING,"Warning: no config file specified, using the default config. In order to specify a config file use 'redis-server /path/to/redis.conf'");
}
if (server.daemonize) daemonize();
initServer();
if (server.daemonize) createPidFile();
redisLog(REDIS_NOTICE,"Server started, Redis version " REDIS_VERSION);
#ifdef __linux__
linuxOvercommitMemoryWarning();
#endif
start = ustime();
if (server.ds_enabled) {
redisLog(REDIS_NOTICE,"DB not loaded (running with disk back end)");
} else if (server.appendonly) {
if (loadAppendOnlyFile(server.appendfilename) == REDIS_OK)
redisLog(REDIS_NOTICE,"DB loaded from append only file: %.3f seconds",(float)(ustime()-start)/1000000);
} else {
if (rdbLoad(server.dbfilename) == REDIS_OK)
redisLog(REDIS_NOTICE,"DB loaded from disk: %.3f seconds",(float)(ustime()-start)/1000000);
}
if (server.ipfd > 0)
redisLog(REDIS_NOTICE,"The server is now ready to accept connections on port %d", server.port);
if (server.sofd > 0)
redisLog(REDIS_NOTICE,"The server is now ready to accept connections at %s", server.unixsocket);
aeSetBeforeSleepProc(server.el,beforeSleep);
aeMain(server.el);
aeDeleteEventLoop(server.el);
return 0;
}
#ifdef HAVE_BACKTRACE
static void *getMcontextEip(ucontext_t *uc) {
#if defined(__FreeBSD__)
return (void*) uc->uc_mcontext.mc_eip;
#elif defined(__dietlibc__)
return (void*) uc->uc_mcontext.eip;
#elif defined(__APPLE__) && !defined(MAC_OS_X_VERSION_10_6)
#if __x86_64__
return (void*) uc->uc_mcontext->__ss.__rip;
#else
return (void*) uc->uc_mcontext->__ss.__eip;
#endif
#elif defined(__APPLE__) && defined(MAC_OS_X_VERSION_10_6)
#if defined(_STRUCT_X86_THREAD_STATE64) && !defined(__i386__)
return (void*) uc->uc_mcontext->__ss.__rip;
#else
return (void*) uc->uc_mcontext->__ss.__eip;
#endif
#elif defined(__i386__)
return (void*) uc->uc_mcontext.gregs[14]; /* Linux 32 */
#elif defined(__X86_64__) || defined(__x86_64__)
return (void*) uc->uc_mcontext.gregs[16]; /* Linux 64 */
#elif defined(__ia64__) /* Linux IA64 */
return (void*) uc->uc_mcontext.sc_ip;
#else
return NULL;
#endif
}
static void sigsegvHandler(int sig, siginfo_t *info, void *secret) {
void *trace[100];
char **messages = NULL;
int i, trace_size = 0;
ucontext_t *uc = (ucontext_t*) secret;
sds infostring;
struct sigaction act;
REDIS_NOTUSED(info);
redisLog(REDIS_WARNING,
"======= Ooops! Redis %s got signal: -%d- =======", REDIS_VERSION, sig);
infostring = genRedisInfoString("all");
redisLogRaw(REDIS_WARNING, infostring);
/* It's not safe to sdsfree() the returned string under memory
* corruption conditions. Let it leak as we are going to abort */
trace_size = backtrace(trace, 100);
/* overwrite sigaction with caller's address */
if (getMcontextEip(uc) != NULL) {
trace[1] = getMcontextEip(uc);
}
messages = backtrace_symbols(trace, trace_size);
for (i=1; i<trace_size; ++i)
redisLog(REDIS_WARNING,"%s", messages[i]);
/* free(messages); Don't call free() with possibly corrupted memory. */
if (server.daemonize) unlink(server.pidfile);
/* Make sure we exit with the right signal at the end. So for instance
* the core will be dumped if enabled. */
sigemptyset (&act.sa_mask);
/* When the SA_SIGINFO flag is set in sa_flags then sa_sigaction
* is used. Otherwise, sa_handler is used */
act.sa_flags = SA_NODEFER | SA_ONSTACK | SA_RESETHAND;
act.sa_handler = SIG_DFL;
sigaction (sig, &act, NULL);
kill(getpid(),sig);
}
#endif /* HAVE_BACKTRACE */
static void sigtermHandler(int sig) {
REDIS_NOTUSED(sig);
redisLog(REDIS_WARNING,"Received SIGTERM, scheduling shutdown...");
server.shutdown_asap = 1;
}
void setupSignalHandlers(void) {
struct sigaction act;
/* When the SA_SIGINFO flag is set in sa_flags then sa_sigaction is used.
* Otherwise, sa_handler is used. */
sigemptyset(&act.sa_mask);
act.sa_flags = SA_NODEFER | SA_ONSTACK | SA_RESETHAND;
act.sa_handler = sigtermHandler;
sigaction(SIGTERM, &act, NULL);
#ifdef HAVE_BACKTRACE
sigemptyset(&act.sa_mask);
act.sa_flags = SA_NODEFER | SA_ONSTACK | SA_RESETHAND | SA_SIGINFO;
act.sa_sigaction = sigsegvHandler;
sigaction(SIGSEGV, &act, NULL);
sigaction(SIGBUS, &act, NULL);
sigaction(SIGFPE, &act, NULL);
sigaction(SIGILL, &act, NULL);
#endif
return;
}
/* The End */