void rpoplpushCommand(redisClient *c) {
robj *sobj, *value;
if ((sobj = lookupKeyWriteOrReply(c,c->argv[1],shared.nullbulk)) == NULL ||
checkType(c,sobj,REDIS_LIST)) return;
if (listTypeLength(sobj) == 0) {
addReply(c,shared.nullbulk);
} else {
robj *dobj = lookupKeyWrite(c->db,c->argv[2]);
robj *touchedkey = c->argv[1];
if (dobj && checkType(c,dobj,REDIS_LIST)) return;
value = listTypePop(sobj,REDIS_TAIL);
/* We saved touched key, and protect it, since rpoplpushHandlePush
* may change the client command argument vector. */
incrRefCount(touchedkey);
rpoplpushHandlePush(c,c,c->argv[2],dobj,value);
/* listTypePop returns an object with its refcount incremented */
decrRefCount(value);
/* Delete the source list when it is empty */
if (listTypeLength(sobj) == 0) dbDelete(c->db,touchedkey);
signalModifiedKey(c->db,touchedkey);
decrRefCount(touchedkey);
server.dirty++;
}
}
/* This is the semantic of this command:
* RPOPLPUSH srclist dstlist:
* IF LLEN(srclist) > 0
* element = RPOP srclist
* LPUSH dstlist element
* RETURN element
* ELSE
* RETURN nil
* END
* END
*
* The idea is to be able to get an element from a list in a reliable way
* since the element is not just returned but pushed against another list
* as well. This command was originally proposed by Ezra Zygmuntowicz.
*/
void rpoplpushcommand(redisClient *c) {
robj *sobj, *value;
if ((sobj = lookupKeyWriteOrReply(c,c->argv[1],shared.nullbulk)) == NULL ||
checkType(c,sobj,REDIS_LIST)) return;
if (listTypeLength(sobj) == 0) {
addReply(c,shared.nullbulk);
} else {
robj *dobj = lookupKeyWrite(c->db,c->argv[2]);
if (dobj && checkType(c,dobj,REDIS_LIST)) return;
value = listTypePop(sobj,REDIS_TAIL);
/* Add the element to the target list (unless it's directly
* passed to some BLPOP-ing client */
if (!handleClientsWaitingListPush(c,c->argv[2],value)) {
/* Create the list if the key does not exist */
if (!dobj) {
dobj = createZiplistObject();
dbAdd(c->db,c->argv[2],dobj);
}
listTypePush(dobj,value,REDIS_HEAD);
}
/* Send the element to the client as reply as well */
addReplyBulk(c,value);
/* listTypePop returns an object with its refcount incremented */
decrRefCount(value);
/* Delete the source list when it is empty */
if (listTypeLength(sobj) == 0) dbDelete(c->db,c->argv[1]);
touchWatchedKey(c->db,c->argv[1]);
server.dirty++;
}
}
void rpoplpushCommand(redisClient *c) {
robj *sobj, *value;
if ((sobj = lookupKeyWriteOrReply(c,c->argv[1],shared.nullbulk)) == NULL ||
checkType(c,sobj,REDIS_LIST)) return;
if (listTypeLength(sobj) == 0) {
/* This may only happen after loading very old RDB files. Recent
* versions of Redis delete keys of empty lists. */
addReply(c,shared.nullbulk);
} else {
robj *dobj = lookupKeyWrite(c->db,c->argv[2]);
robj *touchedkey = c->argv[1];
if (dobj && checkType(c,dobj,REDIS_LIST)) return;
value = listTypePop(sobj,REDIS_TAIL);
/* We saved touched key, and protect it, since rpoplpushHandlePush
* may change the client command argument vector (it does not
* currently). */
incrRefCount(touchedkey);
rpoplpushHandlePush(c,c->argv[2],dobj,value);
/* listTypePop returns an object with its refcount incremented */
decrRefCount(value);
/* Delete the source list when it is empty */
if (listTypeLength(sobj) == 0) {
dbDelete(c->db,touchedkey);
}
signalModifiedKey(c->db,touchedkey);
decrRefCount(touchedkey);
}
}
//POP命令的底层实现，where保存pop的位置
void popGenericCommand(client *c, int where) {
//以写操作取出key对象的value值
robj *o = lookupKeyWriteOrReply(c,c->argv[1],shared.nullbulk);
// 如果key没找到或value对象不是列表类型则直接返回
if (o == NULL || checkType(c,o,OBJ_LIST)) return;
//从where 弹出一个value
robj *value = listTypePop(o,where);
//如果value为空，则发送空信息
if (value == NULL) {
addReply(c,shared.nullbulk);
} else {
//保存时间名称
char *event = (where == LIST_HEAD) ? "lpop" : "rpop";
//发送value给client
addReplyBulk(c,value);
//释放value对象
decrRefCount(value);
//发送事件通知
notifyKeyspaceEvent(NOTIFY_LIST,event,c->argv[1],c->db->id);
//如果弹出一个元素后，列表为空
if (listTypeLength(o) == 0) {
//发送"del"时间通知
notifyKeyspaceEvent(NOTIFY_GENERIC,"del",
c->argv[1],c->db->id);
//从数据库中删除当前的key
dbDelete(c->db,c->argv[1]);
}
//当数据库的键被改动，则会调用该函数发送信号
signalModifiedKey(c->db,c->argv[1]);
//更新脏键
server.dirty++;
}
}
/* Blocking RPOP/LPOP */
void blockingPopGenericCommand(redisClient *c, int where) {
robj *o;
mstime_t timeout;
int j;
int slotnum;
if (getTimeoutFromObjectOrReply(c,c->argv[c->argc-1],&timeout,UNIT_SECONDS)
!= REDIS_OK) return;
for (j = 1; j < c->argc-1; j++) {
slotnum = keyHashSlot(c->argv[j]->ptr, sdslen(c->argv[j]->ptr));
o = lookupKeyWrite(c->db,c->argv[j],slotnum);
if (o != NULL) {
if (o->type != REDIS_LIST) {
addReply(c,shared.wrongtypeerr);
return;
} else {
if (listTypeLength(o) != 0) {
/* Non empty list, this is like a non normal [LR]POP. */
char *event = (where == REDIS_HEAD) ? "lpop" : "rpop";
robj *value = listTypePop(o,where);
redisAssert(value != NULL);
addReplyMultiBulkLen(c,2);
addReplyBulk(c,c->argv[j]);
addReplyBulk(c,value);
decrRefCount(value);
notifyKeyspaceEvent(REDIS_NOTIFY_LIST,event,
c->argv[j],c->db->id);
if (listTypeLength(o) == 0) {
dbDelete(c->db,c->argv[j],slotnum);
notifyKeyspaceEvent(REDIS_NOTIFY_GENERIC,"del",
c->argv[j],c->db->id);
}
signalModifiedKey(c->db,c->argv[j],slotnum);
server.dirty++;
/* Replicate it as an [LR]POP instead of B[LR]POP. */
rewriteClientCommandVector(c,2,
(where == REDIS_HEAD) ? shared.lpop : shared.rpop,
c->argv[j]);
return;
}
}
}
}
/* If we are inside a MULTI/EXEC and the list is empty the only thing
* we can do is treating it as a timeout (even with timeout 0). */
if (c->flags & REDIS_MULTI) {
addReply(c,shared.nullmultibulk);
return;
}
/* If the list is empty or the key does not exists we must block */
blockForKeys(c, c->argv + 1, c->argc - 2, timeout, NULL);
}
// RPOPLPUSH source destination
// RPOPLPUSH命令的实现
void rpoplpushCommand(client *c) {
robj *sobj, *value;
//以写操作读取source对象的值，并且检查数据类型是否为OBJ_LIST
if ((sobj = lookupKeyWriteOrReply(c,c->argv[1],shared.nullbulk)) == NULL ||
checkType(c,sobj,OBJ_LIST)) return;
//如果列表长度为0，没有元素，直接发送空信息
if (listTypeLength(sobj) == 0) {
/* This may only happen after loading very old RDB files. Recent
* versions of Redis delete keys of empty lists. */
addReply(c,shared.nullbulk);
} else {
//以写操作读取destination对象的值
robj *dobj = lookupKeyWrite(c->db,c->argv[2]);
robj *touchedkey = c->argv[1]; //将source键备份
//如果目标对象类型是否是列表类型
if (dobj && checkType(c,dobj,OBJ_LIST)) return;
//从source尾部弹出一个元素
value = listTypePop(sobj,LIST_TAIL);
/* We saved touched key, and protect it, since rpoplpushHandlePush
* may change the client command argument vector (it does not
* currently). */
//备份一份source键，因为rpoplpushHandlePush可能会更改client命令行参数
incrRefCount(touchedkey);
//将一个value推入到destination列表头部，如果destination列表不存在，则新创建一个
rpoplpushHandlePush(c,c->argv[2],dobj,value);
/* listTypePop returns an object with its refcount incremented */
decrRefCount(value); //将弹出的value释放
/* Delete the source list when it is empty */
//发送"rpop"时间通知
notifyKeyspaceEvent(NOTIFY_LIST,"rpop",touchedkey,c->db->id);
//如果source列表为空了，则删除key
if (listTypeLength(sobj) == 0) {
//删除之前备份的key键
dbDelete(c->db,touchedkey);
//发送"rpop"时间通知
notifyKeyspaceEvent(NOTIFY_GENERIC,"del",
touchedkey,c->db->id);
}
//当数据库的键被改动，则会调用该函数发送信号
signalModifiedKey(c->db,touchedkey);
//释放备份的source键
decrRefCount(touchedkey);
//脏键加1
server.dirty++;
}
}
void popGenericCommand(redisClient *c, int where) {
robj *o = lookupKeyWriteOrReply(c,c->argv[1],shared.nullbulk);
if (o == NULL || checkType(c,o,REDIS_LIST)) return;
robj *value = listTypePop(o,where);
if (value == NULL) {
addReply(c,shared.nullbulk);
} else {
addReplyBulk(c,value);
decrRefCount(value);
if (listTypeLength(o) == 0) dbDelete(c->db,c->argv[1]);
signalModifiedKey(c->db,c->argv[1]);
server.dirty++;
}
}
void popGenericCommand(redisClient *c, int where) {
robj *o = lookupKeyWriteOrReply(c,c->argv[1],shared.nullbulk);
if (o == NULL || checkType(c,o,REDIS_LIST)) return;
robj *value = listTypePop(o,where);
if (value == NULL) {
addReply(c,shared.nullbulk);
} else {
char *event = (where == REDIS_HEAD) ? "lpop" : "rpop";
addReplyBulk(c,value);
decrRefCount(value);
notifyKeyspaceEvent(REDIS_NOTIFY_LIST,event,c->argv[1],c->db->id);
if (listTypeLength(o) == 0) {
notifyKeyspaceEvent(REDIS_NOTIFY_GENERIC,"del",
c->argv[1],c->db->id);
dbDelete(c->db,c->argv[1]);
}
signalModifiedKey(c->db,c->argv[1]);
server.dirty++;
}
}
void rpoplpushCommand(redisClient *c) {
robj *sobj, *value;
if ((sobj = lookupKeyWriteOrReply(c,c->argv[1],shared.nullbulk)) == NULL ||
checkType(c,sobj,REDIS_LIST)) return;
if (listTypeLength(sobj) == 0) {
addReply(c,shared.nullbulk);
} else {
robj *dobj = lookupKeyWrite(c->db,c->argv[2]);
if (dobj && checkType(c,dobj,REDIS_LIST)) return;
value = listTypePop(sobj,REDIS_TAIL);
rpoplpushHandlePush(c,c->argv[2],dobj,value);
/* listTypePop returns an object with its refcount incremented */
decrRefCount(value);
/* Delete the source list when it is empty */
if (listTypeLength(sobj) == 0) dbDelete(c->db,c->argv[1]);
touchWatchedKey(c->db,c->argv[1]);
server.dirty++;
}
}
void rpoplpushCommand(redisClient *c) {
robj *sobj, *value;
if ((sobj = lookupKeyWriteOrReply(c,c->argv[1],shared.nullbulk)) == NULL ||
checkType(c,sobj,REDIS_LIST)) return;
if (listTypeLength(sobj) == 0) {
/* This may only happen after loading very old RDB files. Recent
* versions of Redis delete keys of empty lists. */
addReply(c,shared.nullbulk);
} else {
robj *dobj = lookupKeyWrite(c->db,c->argv[2]);
robj *touchedkey = c->argv[1];
if (dobj && checkType(c,dobj,REDIS_LIST)) return;
value = listTypePop(sobj,REDIS_TAIL);
/* We saved touched key, and protect it, since rpoplpushHandlePush
* may change the client command argument vector. */
incrRefCount(touchedkey);
rpoplpushHandlePush(c,c,c->argv[2],dobj,value);
/* listTypePop returns an object with its refcount incremented */
decrRefCount(value);
/* Delete the source list when it is empty */
if (listTypeLength(sobj) == 0) dbDelete(c->db,touchedkey);
signalModifiedKey(c->db,touchedkey);
decrRefCount(touchedkey);
server.dirty++;
/* Replicate this as a simple RPOP since the LPUSH side is replicated
* by rpoplpushHandlePush() call if needed (it may not be needed
* if a client is blocking wait a push against the list). */
rewriteClientCommandVector(c,2,
resetRefCount(createStringObject("RPOP",4)),
c->argv[1]);
}
}
/* This function should be called by Redis every time a single command,
* a MULTI/EXEC block, or a Lua script, terminated its execution after
* being called by a client.
*
* All the keys with at least one client blocked that received at least
* one new element via some PUSH operation are accumulated into
* the server.ready_keys list. This function will run the list and will
* serve clients accordingly. Note that the function will iterate again and
* again as a result of serving BRPOPLPUSH we can have new blocking clients
* to serve because of the PUSH side of BRPOPLPUSH. */
void handleClientsBlockedOnLists(void) {
while(listLength(server.ready_keys) != 0) {
list *l;
/* Point server.ready_keys to a fresh list and save the current one
* locally. This way as we run the old list we are free to call
* signalListAsReady() that may push new elements in server.ready_keys
* when handling clients blocked into BRPOPLPUSH. */
l = server.ready_keys;
server.ready_keys = listCreate();
while(listLength(l) != 0) {
robj *o;
listNode *ln = listFirst(l);
readyList *rl = ln->value;
/* First of all remove this key from db->ready_keys so that
* we can safely call signalListAsReady() against this key. */
dictDelete(rl->db->ready_keys,rl->key);
/* If the key exists and it's a list, serve blocked clients
* with data. */
o = lookupKeyWrite(rl->db,rl->key);
if (o != NULL && o->type == REDIS_LIST) {
dictEntry *de;
/* We serve clients in the same order they blocked for
* this key, from the first blocked to the last. */
de = dictFind(rl->db->blocking_keys,rl->key);
if (de) {
list *clients = dictGetVal(de);
int numclients = listLength(clients);
while(numclients--) {
listNode *clientnode = listFirst(clients);
redisClient *receiver = clientnode->value;
robj *dstkey = receiver->bpop.target;
int where = (receiver->lastcmd &&
receiver->lastcmd->proc == blpopCommand) ?
REDIS_HEAD : REDIS_TAIL;
robj *value = listTypePop(o,where);
if (value) {
/* Protect receiver->bpop.target, that will be
* freed by the next unblockClientWaitingData()
* call. */
if (dstkey) incrRefCount(dstkey);
unblockClientWaitingData(receiver);
if (serveClientBlockedOnList(receiver,
rl->key,dstkey,rl->db,value,
where) == REDIS_ERR)
{
/* If we failed serving the client we need
* to also undo the POP operation. */
listTypePush(o,value,where);
}
if (dstkey) decrRefCount(dstkey);
decrRefCount(value);
} else {
break;
}
}
}
if (listTypeLength(o) == 0) dbDelete(rl->db,rl->key);
/* We don't call signalModifiedKey() as it was already called
* when an element was pushed on the list. */
}
/* Free this item. */
decrRefCount(rl->key);
zfree(rl);
listDelNode(l,ln);
}
listRelease(l); /* We have the new list on place at this point. */
}
}
// BRPOP BLPOP 命令的底层实现
// BLPOP key [key ...] timeout
void blockingPopGenericCommand(client *c, int where) {
robj *o;
mstime_t timeout;
int j;
// 以秒为单位取出timeout值
if (getTimeoutFromObjectOrReply(c,c->argv[c->argc-1],&timeout,UNIT_SECONDS)
!= C_OK) return;
//遍历所有的key
for (j = 1; j < c->argc-1; j++) {
//以写操作取出当前key的值
o = lookupKeyWrite(c->db,c->argv[j]);
// value对象不为空
if (o != NULL) {
// 如果value对象的类型不是列表类型，发送类型错误信息
if (o->type != OBJ_LIST) {
addReply(c,shared.wrongtypeerr);
return;
} else {
// 列表长度不为0
if (listTypeLength(o) != 0) {
/* Non empty list, this is like a non normal [LR]POP. */
// 保存事件名称
char *event = (where == LIST_HEAD) ? "lpop" : "rpop";
// 保存弹出的value对象
robj *value = listTypePop(o,where);
serverAssert(value != NULL);
// 发送回复给client
addReplyMultiBulkLen(c,2);
addReplyBulk(c,c->argv[j]);
addReplyBulk(c,value);
// 释放value
decrRefCount(value);
// 发送事件通知
notifyKeyspaceEvent(NOTIFY_LIST,event,
c->argv[j],c->db->id);
//如果弹出元素后列表为空
if (listTypeLength(o) == 0) {
//从数据库中删除当前的key
dbDelete(c->db,c->argv[j]);
// 发送"del"的事件通知
notifyKeyspaceEvent(NOTIFY_GENERIC,"del",
c->argv[j],c->db->id);
}
//数据库的键被修改，发送信号
signalModifiedKey(c->db,c->argv[j]);
//更新脏键
server.dirty++;
/* Replicate it as an [LR]POP instead of B[LR]POP. */
// 传播一个[LR]POP 而不是B[LR]POP
rewriteClientCommandVector(c,2,
(where == LIST_HEAD) ? shared.lpop : shared.rpop,
c->argv[j]);
return;
}
}
}
}
/* If we are inside a MULTI/EXEC and the list is empty the only thing
* we can do is treating it as a timeout (even with timeout 0). */
// 如果命令在一个事务中执行，则发送一个空回复以避免死等待
if (c->flags & CLIENT_MULTI) {
addReply(c,shared.nullmultibulk);
return;
}
/* If the list is empty or the key does not exists we must block */
// 参数中的所有键都不存在，则阻塞这些键
blockForKeys(c, c->argv + 1, c->argc - 2, timeout, NULL);
}
//函数会在redis每次执行完单个命令，事务块或lua脚本之后被调用
//对于所有被阻塞在client的key来说，只要key被执行了PUSH，那么这个key会被加入到server.ready_keys中
//处理client的阻塞状态
void handleClientsBlockedOnLists(void) {
//只要server.ready_keys还有要解除阻塞的key，就循环遍历server.ready_keys链表
while(listLength(server.ready_keys) != 0) {
list *l;
/* Point server.ready_keys to a fresh list and save the current one
* locally. This way as we run the old list we are free to call
* signalListAsReady() that may push new elements in server.ready_keys
* when handling clients blocked into BRPOPLPUSH. */
//备份一个server.ready_keys链表
l = server.ready_keys;
//生成一个新的空链表
server.ready_keys = listCreate();
//只要链表中还有就绪的key
while(listLength(l) != 0) {
listNode *ln = listFirst(l); //链表头结点地址
readyList *rl = ln->value; //保存链表节点的值，每个值都是readyList结构
/* First of all remove this key from db->ready_keys so that
* we can safely call signalListAsReady() against this key. */
//从rl->db->ready_keys中删除就绪的key
dictDelete(rl->db->ready_keys,rl->key);
/* If the key exists and it's a list, serve blocked clients
* with data. */
//以读操作将就绪key的值读出来
robj *o = lookupKeyWrite(rl->db,rl->key);
//读出的value对象必须是列表类型
if (o != NULL && o->type == OBJ_LIST) {
dictEntry *de;
/* We serve clients in the same order they blocked for
* this key, from the first blocked to the last. */
// blocking_keys是一个字典，字典的键是造成client阻塞的键，字典的值是链表，保存被阻塞的client
// 根据key取出被阻塞的client
de = dictFind(rl->db->blocking_keys,rl->key);
// 链表非空
if (de) {
// 获取de节点的值
list *clients = dictGetVal(de);
// 获取链表的长度
int numclients = listLength(clients);
//遍历链表的所有节点
while(numclients--) {
// 第一个client节点地址
listNode *clientnode = listFirst(clients);
// 取出节点的值，是一个client类型
client *receiver = clientnode->value;
// 从client类型中的target获得要PUSH出的dstkey，该键保存在target中
robj *dstkey = receiver->bpop.target;
// 获取弹出的位置，根据BRPOPLPUSH命令
int where = (receiver->lastcmd &&
receiver->lastcmd->proc == blpopCommand) ?
LIST_HEAD : LIST_TAIL;
// 从列表中弹出元素
robj *value = listTypePop(o,where);
// 弹出成功
if (value) {
/* Protect receiver->bpop.target, that will be
* freed by the next unblockClient()
* call. */
//增加dstkey的引用计数，保护该键，在unblockClient函数中释放
if (dstkey) incrRefCount(dstkey);
//取消client的阻塞状态
unblockClient(receiver);
// 将value推入造成client阻塞的键上，
if (serveClientBlockedOnList(receiver,
rl->key,dstkey,rl->db,value,
where) == C_ERR)
{
/* If we failed serving the client we need
* to also undo the POP operation. */
// 如果推入失败，则需要键弹出的value还原回去
listTypePush(o,value,where);
}
// 释放dstkey和value
if (dstkey) decrRefCount(dstkey);
decrRefCount(value);
} else {
break;
}
}
}
// 如果弹出了所有元素，将key从数据库中删除
if (listTypeLength(o) == 0) {
dbDelete(rl->db,rl->key);
}
/* We don't call signalModifiedKey() as it was already called
* when an element was pushed on the list. */
}
/* Free this item. */
//释放所有空间
decrRefCount(rl->key);
zfree(rl);
listDelNode(l,ln);
}
//释放原来的ready_keys，因为之前创建了新的链表
listRelease(l); /* We have the new list on place at this point. */
}
}
/* This function should be called by Redis every time a single command,
* a MULTI/EXEC block, or a Lua script, terminated its execution after
* being called by a client.
*
* All the keys with at least one client blocked that received at least
* one new element via some PUSH/XADD operation are accumulated into
* the server.ready_keys list. This function will run the list and will
* serve clients accordingly. Note that the function will iterate again and
* again as a result of serving BRPOPLPUSH we can have new blocking clients
* to serve because of the PUSH side of BRPOPLPUSH. */
void handleClientsBlockedOnKeys(void) {
while(listLength(server.ready_keys) != 0) {
list *l;
/* Point server.ready_keys to a fresh list and save the current one
* locally. This way as we run the old list we are free to call
* signalKeyAsReady() that may push new elements in server.ready_keys
* when handling clients blocked into BRPOPLPUSH. */
l = server.ready_keys;
server.ready_keys = listCreate();
while(listLength(l) != 0) {
listNode *ln = listFirst(l);
readyList *rl = ln->value;
/* First of all remove this key from db->ready_keys so that
* we can safely call signalKeyAsReady() against this key. */
dictDelete(rl->db->ready_keys,rl->key);
/* Serve clients blocked on list key. */
robj *o = lookupKeyWrite(rl->db,rl->key);
if (o != NULL && o->type == OBJ_LIST) {
dictEntry *de;
/* We serve clients in the same order they blocked for
* this key, from the first blocked to the last. */
de = dictFind(rl->db->blocking_keys,rl->key);
if (de) {
list *clients = dictGetVal(de);
int numclients = listLength(clients);
while(numclients--) {
listNode *clientnode = listFirst(clients);
client *receiver = clientnode->value;
if (receiver->btype != BLOCKED_LIST) {
/* Put on the tail, so that at the next call
* we'll not run into it again. */
listDelNode(clients,clientnode);
listAddNodeTail(clients,receiver);
continue;
}
robj *dstkey = receiver->bpop.target;
int where = (receiver->lastcmd &&
receiver->lastcmd->proc == blpopCommand) ?
LIST_HEAD : LIST_TAIL;
robj *value = listTypePop(o,where);
if (value) {
/* Protect receiver->bpop.target, that will be
* freed by the next unblockClient()
* call. */
if (dstkey) incrRefCount(dstkey);
unblockClient(receiver);
if (serveClientBlockedOnList(receiver,
rl->key,dstkey,rl->db,value,
where) == C_ERR)
{
/* If we failed serving the client we need
* to also undo the POP operation. */
listTypePush(o,value,where);
}
if (dstkey) decrRefCount(dstkey);
decrRefCount(value);
} else {
break;
}
}
}
if (listTypeLength(o) == 0) {
dbDelete(rl->db,rl->key);
notifyKeyspaceEvent(NOTIFY_GENERIC,"del",rl->key,rl->db->id);
}
/* We don't call signalModifiedKey() as it was already called
* when an element was pushed on the list. */
}
/* Serve clients blocked on stream key. */
else if (o != NULL && o->type == OBJ_STREAM) {
dictEntry *de = dictFind(rl->db->blocking_keys,rl->key);
stream *s = o->ptr;
/* We need to provide the new data arrived on the stream
* to all the clients that are waiting for an offset smaller
* than the current top item. */
if (de) {
list *clients = dictGetVal(de);
listNode *ln;
listIter li;
listRewind(clients,&li);
while((ln = listNext(&li))) {
client *receiver = listNodeValue(ln);
if (receiver->btype != BLOCKED_STREAM) continue;
streamID *gt = dictFetchValue(receiver->bpop.keys,
rl->key);
if (s->last_id.ms > gt->ms ||
(s->last_id.ms == gt->ms &&
s->last_id.seq > gt->seq))
{
streamID start = *gt;
start.seq++; /* Can't overflow, it's an uint64_t */
/* If we blocked in the context of a consumer
* group, we need to resolve the group and
* consumer here. */
streamCG *group = NULL;
streamConsumer *consumer = NULL;
if (receiver->bpop.xread_group) {
group = streamLookupCG(s,
receiver->bpop.xread_group->ptr);
/* In theory if the group is not found we
* just perform the read without the group,
* but actually when the group, or the key
* itself is deleted (triggering the removal
* of the group), we check for blocked clients
* and send them an error. */
}
if (group) {
consumer = streamLookupConsumer(group,
receiver->bpop.xread_consumer->ptr,
1);
}
/* Note that after we unblock the client, 'gt'
* and other receiver->bpop stuff are no longer
* valid, so we must do the setup above before
* this call. */
unblockClient(receiver);
/* Emit the two elements sub-array consisting of
* the name of the stream and the data we
* extracted from it. Wrapped in a single-item
* array, since we have just one key. */
addReplyMultiBulkLen(receiver,1);
addReplyMultiBulkLen(receiver,2);
addReplyBulk(receiver,rl->key);
streamPropInfo pi = {
rl->key,
receiver->bpop.xread_group
};
streamReplyWithRange(receiver,s,&start,NULL,
receiver->bpop.xread_count,
0, group, consumer, 0, &pi);
}
}
}
}
/* Free this item. */
decrRefCount(rl->key);
zfree(rl);
listDelNode(l,ln);
}
listRelease(l); /* We have the new list on place at this point. */
}
}
