/* On FLUSHDB or FLUSHALL all the watched keys that are present before the
* flush but will be deleted as effect of the flushing operation should
* be touched. "dbid" is the DB that's getting the flush. -1 if it is
* a FLUSHALL operation (all the DBs flushed).
*
* 当一个数据库被 FLUSHDB 或者 FLUSHALL 清空时，
* 它数据库内的所有 key 都应该被触碰。
*
* dbid 参数指定要被 FLUSH 的数据库。
*
* 如果 dbid 为 -1 ，那么表示执行的是 FLUSHALL ，
* 所有数据库都将被 FLUSH
*/
void touchWatchedKeysOnFlush(int dbid) {
listIter li1, li2;
listNode *ln;
// 这里的思路挺有趣的，不是遍历数据库的所有 key 来让客户端变为 DIRTY
// 而是遍历所有客户端，然后遍历客户端监视的键，再让相应的客户端变为 DIRTY
// 后者要比前者高效很多
/* For every client, check all the waited keys */
// 遍历所有客户端
listRewind(server.clients,&li1);
while((ln = listNext(&li1))) {
redisClient *c = listNodeValue(ln);
// 遍历客户端监视的键
listRewind(c->watched_keys,&li2);
while((ln = listNext(&li2))) {
// 取出监视的键和键的数据库
watchedKey *wk = listNodeValue(ln);
/* For every watched key matching the specified DB, if the
* key exists, mark the client as dirty, as the key will be
* removed. */
// 如果数据库号码相同，或者执行的命令为 FLUSHALL
// 那么将客户端设置为 REDIS_DIRTY_CAS
if (dbid == -1 || wk->db->id == dbid) {
if (dictFind(wk->db->dict, wk->key->ptr) != NULL)
c->flags |= REDIS_DIRTY_CAS;
}
}
}
}
// 当数据库执行了FLUSHDB或FLUSHALL命令，所有的key都被清空，那么数据库中的所有的键都被touched
// dbid指定被FLUSH的数据库id，如果dbid为-1，表示执行了FLUSHALL，所有的数据库都被FLUSH
void touchWatchedKeysOnFlush(int dbid) {
listIter li1, li2;
listNode *ln;
/* For every client, check all the waited keys */
listRewind(server.clients,&li1);
// 遍历所有的client
while((ln = listNext(&li1))) {
client *c = listNodeValue(ln);
listRewind(c->watched_keys,&li2);
// 遍历当前client所监视的key
while((ln = listNext(&li2))) {
// 取出被监视的key和关联的数据库
watchedKey *wk = listNodeValue(ln);
/* For every watched key matching the specified DB, if the
* key exists, mark the client as dirty, as the key will be
* removed. */
// 如果数据库id合法
if (dbid == -1 || wk->db->id == dbid) {
// 数据库中存在该key，则设置client的DIRTY_CAS标识
if (dictFind(wk->db->dict, wk->key->ptr) != NULL)
c->flags |= CLIENT_DIRTY_CAS;
}
}
}
}
/*
* 为 FLUSHDB 和 FLUSHALL 特别设置的触碰函数
*
* T = O(N^2)
*/
void touchWatchedKeysOnFlush(int dbid)
{
listIter li1, li2;
listNode *ln;
/* For every client, check all the waited keys */
// 列出所有客户端，O(N)
listRewind(server.clients,&li1);
while((ln = listNext(&li1)))
{
redisClient *c = listNodeValue(ln);
// 列出所有监视 key ,O(N)
listRewind(c->watched_keys,&li2);
while((ln = listNext(&li2)))
{
watchedKey *wk = listNodeValue(ln);
/* For every watched key matching the specified DB, if the
* key exists, mark the client as dirty, as the key will be
* removed. */
// 如果目标 db 和监视 key 的 DB 相同，
// 那么打开客户端的 REDIS_DIRTY_CAS 选项
// O(1)
if (dbid == -1 || wk->db->id == dbid)
{
if (dictFind(wk->db->dict, wk->key->ptr) != NULL)
c->flags |= REDIS_DIRTY_CAS;
}
}
}
}
/* 发布一则消息，即将消息发送给所有订阅了指定频道channel的所有客户端以及所有订阅了和指定频道匹配的模式的客户端。*/
int pubsubPublishMessage(robj *channel, robj *message) {
int receivers = 0;
dictEntry *de;
listNode *ln;
listIter li;
/* Send to clients listening for that channel */
// 取出订阅指定频道的客户端链表
de = dictFind(server.pubsub_channels,channel);
if (de) {
list *list = dictGetVal(de);
listNode *ln;
listIter li;
listRewind(list,&li);
// 遍历该客户端链表，并将消息逐一发送给这些客户端
while ((ln = listNext(&li)) != NULL) {
redisClient *c = ln->value;
// 发送消息
addReply(c,shared.mbulkhdr[3]);
// 回复“message”字符串
addReply(c,shared.messagebulk);
// 回复消息的来源频道
addReplyBulk(c,channel);
// 回复消息内容
addReplyBulk(c,message);
// 统计接收客户端的数量
receivers++;
}
}
/* Send to clients listening to matching channels */
// 将消息发送个订阅了和指定频道匹配的模式的客户端
if (listLength(server.pubsub_patterns)) {
listRewind(server.pubsub_patterns,&li);
channel = getDecodedObject(channel);
// 遍历server.pubsub_patterns
while ((ln = listNext(&li)) != NULL) {
// 取出当前模式
pubsubPattern *pat = ln->value;
// 判断当前模式是否和给定频道相匹配
if (stringmatchlen((char*)pat->pattern->ptr,
sdslen(pat->pattern->ptr),
(char*)channel->ptr,
sdslen(channel->ptr),0)) {
// 发送消息
addReply(pat->client,shared.mbulkhdr[4]);
addReply(pat->client,shared.pmessagebulk);
addReplyBulk(pat->client,pat->pattern);
addReplyBulk(pat->client,channel);
addReplyBulk(pat->client,message);
receivers++;
}
}
decrRefCount(channel);
}
return receivers;
}
void updateSlavesWaitingBgsave(int bgsaveerr){
listNode *ln;
int startbgsave = 0;
listIter li;
listRewind(server.slaves, &li);
while((ln=listNext(&li))){
clientContext *slave = ln->value;
if (slave->repl_state == REPL_WAIT_BGSAVE_START){
startbgsave = 1;
slave->repl_state = REPL_WAIT_BGSAVE_END;
} else if (slave->repl_state == REPL_WAIT_BGSAVE_END) {
if (bgsaveerr != 0){
cc_freeClient(slave);
xlog(LOG_WARN, "replication: 数据同步失败, db 保存子进程返回错误\n");
continue;
}
struct stat buf;
if ( ((slave->repl_dbfd=open(server.dbfilename, O_RDONLY)) == -1) ||
(fstat(slave->repl_dbfd, &buf)==-1))
{
cc_freeClient(slave);
xlog(LOG_WARN, "replication: db 文件打开失败\n");
continue;
}
slave->repl_dboff = 0;
slave->repl_dbsize = buf.st_size;
slave->repl_state = REPL_SEND_DB;
if (multi_deleteFileEvent(server.el, slave->fd, MULTI_WRITABLE) < 0)
{
cc_freeClient(slave);
continue;
}
// 添加发送 db 数据事件函数
if (multi_createFileEvent(server.el, slave->fd, MULTI_WRITABLE,
sendDBToSlave, slave) < 0){
cc_freeClient(slave);
continue;
}
}
}
if (startbgsave){
if (db_bgsave(server.dbfilename) != 0){
listIter li;
listRewind(server.slaves, &li);
xlog(LOG_WARN, "bgsave: db 保存失败\n");
while((ln=listNext(&li))){
clientContext *slave = ln->value;
if (slave->repl_state == REPL_WAIT_BGSAVE_END){
cc_freeClient(slave);
}
}
}
}
}
/* This function is called at the end of every background saving.
* The argument bgsaveerr is REDIS_OK if the background saving succeeded
* otherwise REDIS_ERR is passed to the function.
*
* The goal of this function is to handle slaves waiting for a successful
* background saving in order to perform non-blocking synchronization. */
void updateSlavesWaitingBgsave(int bgsaveerr) {
//backgroundSaveDoneHandler在BGSAVE操作完成后，调用这里来处理可能的从库事件。
listNode *ln;
int startbgsave = 0;
listIter li;
listRewind(server.slaves,&li);
while((ln = listNext(&li))) {//循环遍历每一个从库，查看其状态进行相应的处理。
redisClient *slave = ln->value;
if (slave->replstate == REDIS_REPL_WAIT_BGSAVE_START) {
startbgsave = 1;//刚才在做bgsave的时候，有客户端来请求sync同步，但是我没有理他，现在得给他准备了。
slave->replstate = REDIS_REPL_WAIT_BGSAVE_END;//修改这个状态后，新的写入操作会记录到这个连接的缓存里
} else if (slave->replstate == REDIS_REPL_WAIT_BGSAVE_END) {
//后台保存完成，下面需要发送rdb文件了，丫的够大的
struct redis_stat buf;
if (bgsaveerr != REDIS_OK) {
freeClient(slave);
redisLog(REDIS_WARNING,"SYNC failed. BGSAVE child returned an error");
continue;
}
//打开这个rdb_filename,要准备给这个slave发送数据了。
if ((slave->repldbfd = open(server.rdb_filename,O_RDONLY)) == -1 ||
redis_fstat(slave->repldbfd,&buf) == -1) {
freeClient(slave);
redisLog(REDIS_WARNING,"SYNC failed. Can't open/stat DB after BGSAVE: %s", strerror(errno));
continue;
}
slave->repldboff = 0;
slave->repldbsize = buf.st_size;
//记住此时slave->repldbfd没有关闭，可写事件的时候就不需要打开了。
slave->replstate = REDIS_REPL_SEND_BULK;
aeDeleteFileEvent(server.el,slave->fd,AE_WRITABLE);//删掉之前的可写回调，注册为sendBulkToSlave
if (aeCreateFileEvent(server.el, slave->fd, AE_WRITABLE, sendBulkToSlave, slave) == AE_ERR) {
freeClient(slave);
continue;
}
}
}
if (startbgsave) {//悲剧，又有要sync的，还得保存一次。
if (rdbSaveBackground(server.rdb_filename) != REDIS_OK) {
listIter li;
listRewind(server.slaves,&li);
redisLog(REDIS_WARNING,"SYNC failed. BGSAVE failed");
while((ln = listNext(&li))) {
redisClient *slave = ln->value;
//这下面似乎有问题，replstate已经在上面被设置为了_END。https://github.com/antirez/redis/issues/1308
if (slave->replstate == REDIS_REPL_WAIT_BGSAVE_START)
freeClient(slave);
}
}
}
}
/* This function is called at the end of every backgrond saving.
* The argument bgsaveerr is REDIS_OK if the background saving succeeded
* otherwise REDIS_ERR is passed to the function.
*
* The goal of this function is to handle slaves waiting for a successful
* background saving in order to perform non-blocking synchronization. */
void updateSlavesWaitingBgsave(int bgsaveerr) {
listNode *ln;
int startbgsave = 0;
listIter li;
listRewind(server.slaves,&li);
while((ln = listNext(&li))) {
redisClient *slave = ln->value;
if (slave->replstate == REDIS_REPL_WAIT_BGSAVE_START) {
startbgsave = 1;
slave->replstate = REDIS_REPL_WAIT_BGSAVE_END;
} else if (slave->replstate == REDIS_REPL_WAIT_BGSAVE_END) {
struct redis_stat buf;
if (bgsaveerr != REDIS_OK) {
freeClient(slave);
redisLog(REDIS_WARNING,"SYNC failed. BGSAVE child returned an error");
continue;
}
if ((slave->repldbfd = open(server.dbfilename,O_RDONLY)) == -1 ||
redis_fstat(slave->repldbfd,&buf) == -1) {
freeClient(slave);
redisLog(REDIS_WARNING,"SYNC failed. Can't open/stat DB after BGSAVE: %s", strerror(errno));
continue;
}
slave->repldboff = 0;
slave->repldbsize = buf.st_size;
slave->replstate = REDIS_REPL_SEND_BULK;
aeDeleteFileEvent(server.el,slave->fd,AE_WRITABLE);
if (aeCreateFileEvent(server.el, slave->fd, AE_WRITABLE, sendBulkToSlave, slave) == AE_ERR) {
freeClient(slave);
continue;
}
}
}
if (startbgsave) {
if (rdbSaveBackground(server.dbfilename) != REDIS_OK) {
listIter li;
listRewind(server.slaves,&li);
redisLog(REDIS_WARNING,"SYNC failed. BGSAVE failed");
while((ln = listNext(&li))) {
redisClient *slave = ln->value;
if (slave->replstate == REDIS_REPL_WAIT_BGSAVE_START)
freeClient(slave);
}
}
}
}
/*
* 发布一个消息至指定频道
*/
int pubsubPublishMessage(robj *channel, robj *message) {
int receivers = 0;
dictEntry *de;
listNode *ln;
listIter li;
/* Send to clients listening for that channel */
/* 发布给监听指定频道的客户端 */
de = dictFind(server.pubsub_channels,channel);
if (de) {
list *list = dictGetVal(de);
listNode *ln;
listIter li;
listRewind(list,&li);
while ((ln = listNext(&li)) != NULL) {
redisClient *c = ln->value;
addReply(c,shared.mbulkhdr[3]);
addReply(c,shared.messagebulk);
addReplyBulk(c,channel);
addReplyBulk(c,message);
receivers++;
}
}
/* Send to clients listening to matching channels */
/* 发布给监听模式匹配的客户端 */
if (listLength(server.pubsub_patterns)) {
listRewind(server.pubsub_patterns,&li);
channel = getDecodedObject(channel);
while ((ln = listNext(&li)) != NULL) {
pubsubPattern *pat = ln->value;
if (stringmatchlen((char*)pat->pattern->ptr,
sdslen(pat->pattern->ptr),
(char*)channel->ptr,
sdslen(channel->ptr),0)) {
addReply(pat->client,shared.mbulkhdr[4]);
addReply(pat->client,shared.pmessagebulk);
addReplyBulk(pat->client,pat->pattern);
addReplyBulk(pat->client,channel);
addReplyBulk(pat->client,message);
receivers++;
}
}
decrRefCount(channel);
}
return receivers;
}
/* Unwatch all the keys watched by this client. To clean the EXEC dirty
* flag is up to the caller. */
void unwatchAllKeys(redisClient *c) {
listIter li;
listNode *ln;
if (listLength(c->watched_keys) == 0) return;
listRewind(c->watched_keys,&li);
while((ln = listNext(&li))) {
list *clients;
watchedKey *wk;
/* Lookup the watched key -> clients list and remove the client
* from the list */
wk = listNodeValue(ln);
clients = dictFetchValue(wk->db->watched_keys, wk->key);
redisAssert(clients != NULL);
listDelNode(clients,listSearchKey(clients,c));
/* Kill the entry at all if this was the only client */
if (listLength(clients) == 0)
dictDelete(wk->db->watched_keys, wk->key);
/* Remove this watched key from the client->watched list */
listDelNode(c->watched_keys,ln);
decrRefCount(wk->key);
zfree(wk);
}
}
/* Watch for the specified key */
void watchForKey(redisClient *c, robj *key) {
list *clients = NULL;
listIter li;
listNode *ln;
watchedKey *wk;
/* Check if we are already watching for this key */
listRewind(c->watched_keys,&li);
while((ln = listNext(&li))) {
wk = listNodeValue(ln);
if (wk->db == c->db && equalStringObjects(key,wk->key))
return; /* Key already watched */
}
/* This key is not already watched in this DB. Let's add it */
clients = dictFetchValue(c->db->watched_keys,key);
if (!clients) {
clients = listCreate();
dictAdd(c->db->watched_keys,key,clients);
incrRefCount(key);
}
listAddNodeTail(clients,c);
/* Add the new key to the lits of keys watched by this client */
wk = zmalloc(sizeof(*wk));
wk->key = key;
wk->db = c->db;
incrRefCount(key);
listAddNodeTail(c->watched_keys,wk);
}
/* Unsubscribe from all the patterns. Return the number of patterns the
* client was subscribed from.
*
* 退订客户端 c 订阅的所有模式。
*
* 返回被退订模式的数量。
*/
int pubsubUnsubscribeAllPatterns(redisClient *c, int notify) {
listNode *ln;
listIter li;
int count = 0;
// 迭代客户端订阅模式的链表
listRewind(c->pubsub_patterns,&li);
while ((ln = listNext(&li)) != NULL) {
robj *pattern = ln->value;
// 退订，并计算退订数
count += pubsubUnsubscribePattern(c,pattern,notify);
}
// 如果在执行这个函数时，客户端没有订阅任何模式，
// 那么向客户端发送回复
if (notify && count == 0) {
/* We were subscribed to nothing? Still reply to the client. */
addReply(c,shared.mbulkhdr[3]);
addReply(c,shared.punsubscribebulk);
addReply(c,shared.nullbulk);
addReplyLongLong(c,dictSize(c->pubsub_channels)+
listLength(c->pubsub_patterns));
}
// 退订总数
return count;
}
void replicationFeedSlaves(list *slaves, int dictid, robj **argv, int argc) {
listNode *ln;
listIter li;
int j;
listRewind(slaves,&li);
while((ln = listNext(&li))) {
redisClient *slave = ln->value;
/* Don't feed slaves that are still waiting for BGSAVE to start */
if (slave->replstate == REDIS_REPL_WAIT_BGSAVE_START) continue;
/* Feed slaves that are waiting for the initial SYNC (so these commands
* are queued in the output buffer until the intial SYNC completes),
* or are already in sync with the master. */
if (slave->slaveseldb != dictid) {
robj *selectcmd;
if (dictid >= 0 && dictid < REDIS_SHARED_SELECT_CMDS) {
selectcmd = shared.select[dictid];
incrRefCount(selectcmd);
} else {
selectcmd = createObject(REDIS_STRING,
sdscatprintf(sdsempty(),"select %d\r\n",dictid));
}
addReply(slave,selectcmd);
decrRefCount(selectcmd);
slave->slaveseldb = dictid;
}
addReplyMultiBulkLen(slave,argc);
for (j = 0; j < argc; j++) addReplyBulk(slave,argv[j]);
}
}
void *_masterWatch(void *t)
{
(void)t;
ccache *c;
listIter li;
listNode *ln;
int msecSleep = 1000;
while (1) {
master_numjob = 0;
listRewind(slave_caches,&li);
while ((ln = listNext(&li)) != NULL) {
c = listNodeValue(ln);
_masterProcessCacheNew(c);
_masterProcessFinishedIO();
_masterProcessCacheOld(c);
_masterProcessStatus();
}
if(master_numjob < 1) msecSleep = 10000;
else {
printf("num job %d\n",master_numjob);
msecSleep = 10;
}
/* TODO: flexible sleep time */
usleep(msecSleep);
}
pthread_exit(NULL);
}
// 取消客户端对所有的键的监视，清理 EXEC dirty 标识状态由调用者决定
void unwatchAllKeys(client *c) {
listIter li;
listNode *ln;
// 如果客户端没有监视key则直接返回
if (listLength(c->watched_keys) == 0) return;
listRewind(c->watched_keys,&li);
// 遍历客户端监视的key
while((ln = listNext(&li))) {
list *clients;
watchedKey *wk;
/* Lookup the watched key -> clients list and remove the client
* from the list */
wk = listNodeValue(ln);
// 从数据库中的watched_keys字典中查找出监视key的client
clients = dictFetchValue(wk->db->watched_keys, wk->key);
serverAssertWithInfo(c,NULL,clients != NULL);
// 从client的链表中删除当前client节点
listDelNode(clients,listSearchKey(clients,c));
/* Kill the entry at all if this was the only client */
// 如果client链表为空，标识给key没有被监视
if (listLength(clients) == 0)
// 从数据库的watched_keys中删除该key
dictDelete(wk->db->watched_keys, wk->key);
/* Remove this watched key from the client->watched list */
// 从客户端的watched_keys中删除该节点
listDelNode(c->watched_keys,ln);
decrRefCount(wk->key);
zfree(wk);
}
}
/*
* “碰触”（touch）给定 key ，如果这个 key 正在被监视的话，
* 让监视它的客户端在执行 EXEC 命令时失败。
*
* T = O(N)
*/
void touchWatchedKey(redisDb *db, robj *key)
{
list *clients;
listIter li;
listNode *ln;
// 如果数据库中没有任何 key 被监视，那么直接返回
if (dictSize(db->watched_keys) == 0) return;
// 取出数据库中所有监视给定 key 的客户端
clients = dictFetchValue(db->watched_keys, key);
if (!clients) return;
/* Mark all the clients watching this key as REDIS_DIRTY_CAS */
/* Check if we are already watching for this key */
// 打开所有监视这个 key 的客户端的 REDIS_DIRTY_CAS 状态
// O(N)
listRewind(clients,&li);
while((ln = listNext(&li)))
{
redisClient *c = listNodeValue(ln);
c->flags |= REDIS_DIRTY_CAS;
}
}
// 撤销对这个客户端的所有 WATCH
// 清除 EXEC dirty FLAG 的任务由调用者完成
void unwatchAllKeys(redisClient *c) {
listIter li;
listNode *ln;
// 没有 WATCHED KEY ，直接返回
if (listLength(c->watched_keys) == 0) return;
listRewind(c->watched_keys,&li);
while((ln = listNext(&li))) {
list *clients;
watchedKey *wk;
/* Lookup the watched key -> clients list and remove the client
* from the list */
// 将当前客户端从监视 KEY 的链表中移除
wk = listNodeValue(ln);
clients = dictFetchValue(wk->db->watched_keys, wk->key);
redisAssertWithInfo(c,NULL,clients != NULL);
listDelNode(clients,listSearchKey(clients,c));
/* Kill the entry at all if this was the only client */
// 如果监视 KEY 的只有这个客户端
// 那么将链表从字典中删除
if (listLength(clients) == 0)
dictDelete(wk->db->watched_keys, wk->key);
/* Remove this watched key from the client->watched list */
// 还需要将 KEY 从 client->watched_keys 链表中移除
listDelNode(c->watched_keys,ln);
decrRefCount(wk->key);
zfree(wk);
}
}
/* Remove the 'key' from the list of blocked keys for a given client.
*
* The function returns 1 when there are no longer blocking keys after
* the current one was removed (and the client can be unblocked). */
int dontWaitForSwappedKey(redisClient *c, robj *key) {
list *l;
listNode *ln;
listIter li;
struct dictEntry *de;
/* The key object might be destroyed when deleted from the c->io_keys
* list (and the "key" argument is physically the same object as the
* object inside the list), so we need to protect it. */
incrRefCount(key);
/* Remove the key from the list of keys this client is waiting for. */
listRewind(c->io_keys,&li);
while ((ln = listNext(&li)) != NULL) {
if (equalStringObjects(ln->value,key)) {
listDelNode(c->io_keys,ln);
break;
}
}
redisAssert(ln != NULL);
/* Remove the client form the key => waiting clients map. */
de = dictFind(c->db->io_keys,key);
redisAssert(de != NULL);
l = dictGetEntryVal(de);
ln = listSearchKey(l,c);
redisAssert(ln != NULL);
listDelNode(l,ln);
if (listLength(l) == 0)
dictDelete(c->db->io_keys,key);
decrRefCount(key);
return listLength(c->io_keys) == 0;
}
/* 取消客户端所订阅的所有模式，最后返回退订的模式数量 */
int pubsubUnsubscribeAllPatterns(redisClient *c, int notify) {
listNode *ln;
listIter li;
int count = 0;
// 获取c->pubsub_patterns链表迭代器
listRewind(c->pubsub_patterns,&li);
// 遍历客户端订阅的模式链表，逐一退订
while ((ln = listNext(&li)) != NULL) {
robj *pattern = ln->value;
// 统计退订的模式数量
count += pubsubUnsubscribePattern(c,pattern,notify);
}
// 如果count == 0，说明客户端没有订阅任何模式，回复客户端
if (notify && count == 0) {
/* We were subscribed to nothing? Still reply to the client. */
addReply(c,shared.mbulkhdr[3]);
addReply(c,shared.punsubscribebulk);
addReply(c,shared.nullbulk);
addReplyLongLong(c,dictSize(c->pubsub_channels)+
listLength(c->pubsub_patterns));
}
return count;
}
/* Duplicate the whole list. On out of memory NULL is returned.
* On success a copy of the original list is returned.
*
* The 'Dup' method set with listSetDupMethod() function is used
* to copy the node value. Otherwise the same pointer value of
* the original node is used as value of the copied node.
*
* The original list both on success or error is never modified. */
list *listDup(list *orig)
{
list *copy;
listIter iter;
listNode *node;
if ((copy = listCreate()) == NULL)
return NULL;
copy->dup = orig->dup;
copy->free = orig->free;
copy->match = orig->match;
listRewind(orig, &iter);
while((node = listNext(&iter)) != NULL) {
void *value;
if (copy->dup) {
value = copy->dup(node->value);
if (value == NULL) {
listRelease(copy);
return NULL;
}
} else
value = node->value;
if (listAddNodeTail(copy, value) == NULL) {
listRelease(copy);
return NULL;
}
}
return copy;
}
void dictCounterDestructor(void *privdata, void *val) {
DICT_NOTUSED(privdata);
listNode *ln;
listIter li;
counter *cntr = val;
pubsub *p;
/* Unsubscribe everyone */
if (cntr->subscribers != NULL) {
while (listLength(cntr->subscribers)) {
ln = listFirst(cntr->subscribers);
p = listNodeValue(ln);
pubsubUnsubscribeCounter(p->c,cntr->name,1);
}
}
/* Free all shards */
listRewind(cntr->shards,&li);
while ((ln = listNext(&li)) != NULL) {
shard *shrd = listNodeValue(ln);
zfree(shrd);
}
listRelease(cntr->shards);
if (cntr->want_acks) dictRelease(cntr->want_acks);
/* cntr->name will be freed by the dict code. */
zfree(cntr);
}
void countersSync(clusterNode *node) {
dictIterator *it;
dictEntry *de;
it = dictGetIterator(server.counters);
while ((de = dictNext(it)) != NULL) {
counter *cntr;
listNode *ln;
listIter li;
shard *shrd;
cntr = dictGetVal(de);
/* If we have our own shard make sure to send it's prediction
* to the new node. */
if (cntr->myshard) {
clusterSendShardToNode(cntr, node);
}
listRewind(cntr->shards,&li);
while ((ln = listNext(&li)) != NULL) {
shrd = listNodeValue(ln);
if (memcmp(shrd->node_name, node->name, CLUSTER_NAMELEN) == 0) {
shrd->node = node;
}
}
}
dictReleaseIterator(it);
}
void counterPubSub(counter *cntr, mstime_t now) {
listNode *ln;
listIter li;
if (cntr->subscribers == NULL)
return;
listRewind(cntr->subscribers,&li);
while ((ln = listNext(&li)) != NULL) {
pubsub *p = listNodeValue(ln);
if (p->next > now) {
continue;
}
if (p->lastvalue == cntr->value) {
continue;
}
addReply(p->c,shared.mbulkhdr[3]);
addReply(p->c,shared.messagebulk);
addReplyBulkCBuffer(p->c,cntr->name,sdslen(cntr->name));
addReplyLongDouble(p->c, cntr->value);
p->next = now + p->seconds*1000;
p->lastvalue = cntr->value;
}
}
/* convert a linked list encoding to a list array encoding */
cowListArray *cowConvertListToArray(list *olist) {
listIter li;
listNode *ln;
cowListArray *lar;
listNode *lnNew;
listNode *lnPrev;
unsigned int ix = 0;
lar = (cowListArray *)zmalloc(sizeof(cowListArray) + (sizeof(listNode) * olist->len));
/* add copy of each item from old list */
listRewind(olist,&li);
lnNew = &lar->le[0];
lnPrev = NULL;
while((ln = listNext(&li)) && ix < olist->len) {
/* copy object value to array list
Do not incr ref count. */
lnNew->value = listNodeValue(ln);
lnNew->prev = lnPrev;
if (lnPrev != NULL) {
lnPrev->next = lnNew;
}
lnPrev = lnNew;
lnNew++;
ix++;
}
if (lnPrev != NULL) {
lnPrev->next = NULL;
}
lar->numele = ix;
return lar;
}
void closeTimedoutClients(void) {
redisClient *c;
listNode *ln;
time_t now = time(NULL);
listIter li;
listRewind(server.clients,&li);
while ((ln = listNext(&li)) != NULL) {
c = listNodeValue(ln);
if (server.maxidletime &&
!(c->flags & REDIS_SLAVE) && /* no timeout for slaves */
!(c->flags & REDIS_MASTER) && /* no timeout for masters */
!(c->flags & REDIS_BLOCKED) && /* no timeout for BLPOP */
dictSize(c->pubsub_channels) == 0 && /* no timeout for pubsub */
listLength(c->pubsub_patterns) == 0 &&
(now - c->lastinteraction > server.maxidletime))
{
redisLog(REDIS_VERBOSE,"Closing idle client");
freeClient(c);
} else if (c->flags & REDIS_BLOCKED) {
if (c->blockingto != 0 && c->blockingto < now) {
addReply(c,shared.nullmultibulk);
unblockClientWaitingData(c);
}
}
}
}
int closeTimedoutClients(aeEventLoop *el) {
if(el->myid != 0) {
httpClient *c;
int deletedNodes = 0;
time_t now = time(NULL);
listIter li;
listNode *ln;
listRewind(el->clients,&li);
while ((ln = listNext(&li)) != NULL) {
c = listNodeValue(ln);
if (el->maxidletime &&
(now - c->lastinteraction > el->maxidletime))
{
/* the client is waiting for reply */
if (c->blocked) {
/* This situation happens when request_handler time exceeds client timeout.
* Client timeout is typically 30 seconds and
* Request_handler rarely consumes more than 1 second.
* This rare case has a very small role in overall performance.
*/
listNode *ln = listSearchKey(c->ceList,c);
if(ln) listDelNode(c->ceList,ln);
}
freeClient(c);
deletedNodes++;
}
else break;
}
return deletedNodes;
}
return 0;
}
static void glueReplyBuffersIfNeeded(redisClient *c) {
int copylen = 0;
char buf[GLUEREPLY_UP_TO];
listNode *ln;
listIter li;
robj *o;
listRewind(c->reply,&li);
while((ln = listNext(&li))) {
int objlen;
o = ln->value;
objlen = sdslen(o->ptr);
if (copylen + objlen <= GLUEREPLY_UP_TO) {
memcpy(buf+copylen,o->ptr,objlen);
copylen += objlen;
listDelNode(c->reply,ln);
} else {
if (copylen == 0) return;
break;
}
}
/* Now the output buffer is empty, add the new single element */
o = createObject(REDIS_STRING,sdsnewlen(buf,copylen));
listAddNodeHead(c->reply,o);
}
void replicationFeedMonitors(list *monitors, int dictid, robj **argv, int argc) {
listNode *ln;
listIter li;
int j;
sds cmdrepr = sdsnew("+");
robj *cmdobj;
struct timeval tv;
gettimeofday(&tv,NULL);
cmdrepr = sdscatprintf(cmdrepr,"%ld.%06ld ",(long)tv.tv_sec,(long)tv.tv_usec);
if (dictid != 0) cmdrepr = sdscatprintf(cmdrepr,"(db %d) ", dictid);
for (j = 0; j < argc; j++) {
if (argv[j]->encoding == REDIS_ENCODING_INT) {
cmdrepr = sdscatprintf(cmdrepr, "\"%ld\"", (long)argv[j]->ptr);
} else {
cmdrepr = sdscatrepr(cmdrepr,(char*)argv[j]->ptr,
sdslen(argv[j]->ptr));
}
if (j != argc-1)
cmdrepr = sdscatlen(cmdrepr," ",1);
}
cmdrepr = sdscatlen(cmdrepr,"\r\n",2);
cmdobj = createObject(REDIS_STRING,cmdrepr);
listRewind(monitors,&li);
while((ln = listNext(&li))) {
redisClient *monitor = ln->value;
addReply(monitor,cmdobj);
}
decrRefCount(cmdobj);
}
void countersUpdateValues(void) {
dictIterator *it;
dictEntry *de;
mstime_t now = mstime();
it = dictGetIterator(server.counters);
while ((de = dictNext(it)) != NULL) {
long double elapsed, value = 0;
counter *cntr;
listNode *ln;
listIter li;
shard *shrd;
cntr = dictGetVal(de);
listRewind(cntr->shards,&li);
while ((ln = listNext(&li)) != NULL) {
shrd = listNodeValue(ln);
/* Don't do a prediction with our own shard. */
if (shrd == cntr->myshard) {
value += shrd->value;
continue;
}
/* Don't update predictions for failing nodes. */
if (shrd->node == NULL || nodeFailed(shrd->node)) {
/* Leave the prediction as it is. */
/* TODO: Since this function is called 10 times per second we can't
really do any debug output here. */
/*serverLog(LL_DEBUG,"Counter %s not updating shard of %.40s",
cntr->name, shrd->node_name);*/
} else if (shrd->predict_time > 0 && shrd->predict_value != 0) {
elapsed = now - shrd->predict_time;
shrd->value = shrd->predict_value + (elapsed * shrd->predict_change);
/*serverLog(LL_DEBUG,"Counter %s new value %Lf for shard %.40s",
cntr->name, shrd->value, shrd->node_name);
} else {
serverLog(LL_DEBUG,"Counter %s not using shard of %.40s %llu %Lf",
cntr->name, shrd->node_name, shrd->predict_time, shrd->predict_value);*/
}
value += shrd->value;
}
if (cntr->value != value) {
cntr->value = value;
/* Make sure the cached response gets recalculated. */
cntr->rlen = 0;
}
}
dictReleaseIterator(it);
}
/* Publish a message */
int smempubsubPublishMessage(robj *channel, robj *message)
{
int receivers = 0;
dictEntry *de;
listNode *ln;
listIter li;
int mem_id = -1;
struct smem_t * smem_p = NULL;
listNode *lnode = NULL;
long long ll_var;
/* Get the share memory id */
if(getLongLongFromObject(message,&ll_var) == C_OK){
//serverLog(LL_WARNING,"[smempubsubPublishMessage] get share memory id: %lld", ll_var);
mem_id = ll_var;
// get the item from list
lnode = listSearchKey(server.smem_list_used, &mem_id);
if(lnode){
smem_p = lnode->value;
}else{
//serverLog(LL_WARNING,"[smempubsubPublishMessage] not found the id(%d) in list.", mem_id);
mem_id = -1;
}
}
/* Send to clients listening for that channel */
de = dictFind(server.smempubsub_channels,channel);
if (de) {
list *list = dictGetVal(de);
listNode *ln;
listIter li;
listRewind(list,&li);
while ((ln = listNext(&li)) != NULL) {
client *c = ln->value;
addReply(c,shared.mbulkhdr[3]);
addReply(c,shared.messagebulk);
addReplyBulk(c,channel);
addReplyBulk(c,message);
receivers++;
// if message is share memory id, should increase use count
if(lnode){
smem_p->cnt++;
//serverLog(LL_WARNING,"[smempubsubPublishMessage] receivers:%d, smem_p->cnt=%d.", receivers, smem_p->cnt);
}
}
}
return receivers;
}
void replicationCron(void) {
/* Bulk transfer I/O timeout? */
if (server.masterhost && server.replstate == REDIS_REPL_TRANSFER &&
(time(NULL)-server.repl_transfer_lastio) > REDIS_REPL_TIMEOUT)
{
redisLog(REDIS_WARNING,"Timeout receiving bulk data from MASTER...");
replicationAbortSyncTransfer();
}
/* Timed out master when we are an already connected slave? */
if (server.masterhost && server.replstate == REDIS_REPL_CONNECTED &&
(time(NULL)-server.master->lastinteraction) > REDIS_REPL_TIMEOUT)
{
redisLog(REDIS_WARNING,"MASTER time out: no data nor PING received...");
freeClient(server.master);
}
/* Check if we should connect to a MASTER */
if (server.replstate == REDIS_REPL_CONNECT) {
redisLog(REDIS_NOTICE,"Connecting to MASTER...");
if (syncWithMaster() == REDIS_OK) {
redisLog(REDIS_NOTICE,"MASTER <-> SLAVE sync started: SYNC sent");
if (server.appendonly) rewriteAppendOnlyFileBackground();
}
}
/* If we have attached slaves, PING them from time to time.
* So slaves can implement an explicit timeout to masters, and will
* be able to detect a link disconnection even if the TCP connection
* will not actually go down. */
if (!(server.cronloops % (REDIS_REPL_PING_SLAVE_PERIOD*10))) {
listIter li;
listNode *ln;
listRewind(server.slaves,&li);
while((ln = listNext(&li))) {
redisClient *slave = ln->value;
/* Don't ping slaves that are in the middle of a bulk transfer
* with the master for first synchronization. */
if (slave->replstate == REDIS_REPL_SEND_BULK) continue;
if (slave->replstate == REDIS_REPL_ONLINE) {
/* If the slave is online send a normal ping */
addReplySds(slave,sdsnew("PING\r\n"));
} else {
/* Otherwise we are in the pre-synchronization stage.
* Just a newline will do the work of refreshing the
* connection last interaction time, and at the same time
* we'll be sure that being a single char there are no
* short-write problems. */
write(slave->fd, "\n", 1);
}
}
}
}