//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++;
}
}
/**
* RPOPLPUSH source destination
命令 RPOPLPUSH 在一个原子时间内，执行以下两个动作：
将列表 source 中的最后一个元素(尾元素)弹出，并返回给客户端。
将 source 弹出的元素插入到列表 destination ，作为 destination 列表的的头元素。
举个例子，你有两个列表 source 和 destination ， source 列表有元素 a, b, c ， destination 列表有元素 x, y, z ，
执行 RPOPLPUSH source destination 之后， source 列表包含元素 a, b ，
destination 列表包含元素 c, x, y, z ，并且元素 c 会被返回给客户端。
如果 source 不存在，值 nil 被返回，并且不执行其他动作。
如果 source 和 destination 相同，则列表中的表尾元素被移动到表头，并返回该元素，可以把这种特殊情况视作列表的旋转(rotation)操作。
*/
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 */
notifyKeyspaceEvent(REDIS_NOTIFY_LIST,"rpop",touchedkey,c->db->id);
if (listTypeLength(sobj) == 0) {
dbDelete(c->db,touchedkey);
notifyKeyspaceEvent(REDIS_NOTIFY_GENERIC,"del",
touchedkey,c->db->id);
}
signalModifiedKey(c->db,touchedkey);
decrRefCount(touchedkey);
server.dirty++;
}
}
void sremCommand(redisClient *c) {
robj *set;
int j, deleted = 0, keyremoved = 0;
if ((set = lookupKeyWriteOrReply(c,c->argv[1],shared.czero)) == NULL ||
checkType(c,set,REDIS_SET)) return;
for (j = 2; j < c->argc; j++) {
if (setTypeRemove(set,c->argv[j])) {
deleted++;
if (setTypeSize(set) == 0) {
dbDelete(c->db,c->argv[1]);
keyremoved = 1;
break;
}
}
}
if (deleted) {
signalModifiedKey(c->db,c->argv[1]);
notifyKeyspaceEvent(REDIS_NOTIFY_SET,"srem",c->argv[1],c->db->id);
if (keyremoved)
notifyKeyspaceEvent(REDIS_NOTIFY_GENERIC,"del",c->argv[1],
c->db->id);
server.dirty += deleted;
}
addReplyLongLong(c,deleted);
}
void spopCommand(redisClient *c) {
robj *set, *ele, *aux;
int64_t llele;
int encoding;
if ((set = lookupKeyWriteOrReply(c,c->argv[1],shared.nullbulk)) == NULL ||
checkType(c,set,REDIS_SET)) return;
encoding = setTypeRandomElement(set,&ele,&llele);
if (encoding == REDIS_ENCODING_INTSET) {
ele = createStringObjectFromLongLong(llele);
set->ptr = intsetRemove(set->ptr,llele,NULL);
} else {
incrRefCount(ele);
setTypeRemove(set,ele);
}
notifyKeyspaceEvent(REDIS_NOTIFY_SET,"spop",c->argv[1],c->db->id);
/* Replicate/AOF this command as an SREM operation */
aux = createStringObject("SREM",4);
rewriteClientCommandVector(c,3,aux,c->argv[1],ele);
decrRefCount(ele);
decrRefCount(aux);
addReplyBulk(c,ele);
if (setTypeSize(set) == 0) {
dbDelete(c->db,c->argv[1]);
notifyKeyspaceEvent(REDIS_NOTIFY_GENERIC,"del",c->argv[1],c->db->id);
}
signalModifiedKey(c->db,c->argv[1]);
server.dirty++;
}
void setGenericCommand(redisClient *c, int flags, robj *key, robj *val, robj *expire, int unit, robj *ok_reply, robj *abort_reply) {
long long milliseconds = 0; /* initialized to avoid any harmness warning */
if (expire) {
if (getLongLongFromObjectOrReply(c, expire, &milliseconds, NULL) != REDIS_OK)
return;
if (milliseconds <= 0) {
addReplyErrorFormat(c,"invalid expire time in %s",c->cmd->name);
return;
}
if (unit == UNIT_SECONDS) milliseconds *= 1000;
}
if ((flags & REDIS_SET_NX && lookupKeyWrite(c->db,key) != NULL) ||
(flags & REDIS_SET_XX && lookupKeyWrite(c->db,key) == NULL))
{
addReply(c, abort_reply ? abort_reply : shared.nullbulk);
return;
}
setKey(c->db,key,val);
server.dirty++;
if (expire) setExpire(c->db,key,mstime()+milliseconds);
notifyKeyspaceEvent(REDIS_NOTIFY_STRING,"set",key,c->db->id);
if (expire) notifyKeyspaceEvent(REDIS_NOTIFY_GENERIC,
"expire",key,c->db->id);
addReply(c, ok_reply ? ok_reply : shared.ok);
}
// LTRIM key start stop
// LTRIM命令实现
void ltrimCommand(client *c) {
robj *o;
long start, end, llen, ltrim, rtrim;
//将字符串类型起始地址start和结束地址end转换为long类型保存在start和end中
//如果任意失败，则直接返回
if ((getLongFromObjectOrReply(c, c->argv[2], &start, NULL) != C_OK) ||
(getLongFromObjectOrReply(c, c->argv[3], &end, NULL) != C_OK)) return;
// 以读操作取出key大小的value值，如果value对象不是列表类型，直接返回
if ((o = lookupKeyWriteOrReply(c,c->argv[1],shared.ok)) == NULL ||
checkType(c,o,OBJ_LIST)) return;
//获取列表元素数量
llen = listTypeLength(o);
/* convert negative indexes */
// 将负数范围转换成合法范围
if (start < 0) start = llen+start;
if (end < 0) end = llen+end;
if (start < 0) start = 0;
/* Invariant: start >= 0, so this test will be true when end < 0.
* The range is empty when start > end or start >= length. */
//不合理的范围，移除所有的元素
if (start > end || start >= llen) {
/* Out of range start or start > end result in empty list */
ltrim = llen;
rtrim = 0;
} else {
if (end >= llen) end = llen-1; //end值不能超过元素个数
ltrim = start; //左边界
rtrim = llen-end-1; //右边界
}
/* Remove list elements to perform the trim */
//只对编码为quicklist类型的value对象操作
if (o->encoding == OBJ_ENCODING_QUICKLIST) {
quicklistDelRange(o->ptr,0,ltrim); //删除左边界以左的所有元素
quicklistDelRange(o->ptr,-rtrim,rtrim); //删除左边界以右的所有元素
} else {
serverPanic("Unknown list encoding");
}
//发送"ltrim"事件通知
notifyKeyspaceEvent(NOTIFY_LIST,"ltrim",c->argv[1],c->db->id);
//如果将所有元素全部删除完了
if (listTypeLength(o) == 0) {
//从数据库中删除该key
dbDelete(c->db,c->argv[1]);
//发送"del"时间通知
notifyKeyspaceEvent(NOTIFY_GENERIC,"del",c->argv[1],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,c->argv[1]);
//更新脏键
server.dirty++;
//发送ok信息给client
addReply(c,shared.ok);
}
//当key存在时则push，PUSHX，INSERT命令的底层实现
void pushxGenericCommand(client *c, robj *refval, robj *val, int where) {
robj *subject;
listTypeIterator *iter;
listTypeEntry entry;
int inserted = 0;
//以写操作读取key对象的value
//如果读取失败或读取的value对象不是列表类型则返回
if ((subject = lookupKeyWriteOrReply(c,c->argv[1],shared.czero)) == NULL ||
checkType(c,subject,OBJ_LIST)) return;
//寻找基准值refval
if (refval != NULL) {
/* Seek refval from head to tail */
//创建一个列表的迭代器
iter = listTypeInitIterator(subject,0,LIST_TAIL);
//将指向当前的entry节点保存到列表类型的entry中，然后指向下一个entry节点
while (listTypeNext(iter,&entry)) {
//当前的entry节点的值与基准值refval是否相等
if (listTypeEqual(&entry,refval)) {
//如果相等，根据where插入val对象
listTypeInsert(&entry,val,where);
inserted = 1; //设置插入的标识，跳出循环
break;
}
}
//事项迭代器
listTypeReleaseIterator(iter);
//如果插入成功，键值被修改，则发送信号并且发送"linsert"时间通知
if (inserted) {
signalModifiedKey(c->db,c->argv[1]);
notifyKeyspaceEvent(NOTIFY_LIST,"linsert",
c->argv[1],c->db->id);
server.dirty++; //更新脏键
} else {
/* Notify client of a failed insert */
//如果没有插入，则发送插入失败的信息
addReply(c,shared.cnegone);
return;
}
//如果基准值为空
} else {
//根据where判断出事件名称
char *event = (where == LIST_HEAD) ? "lpush" : "rpush";
//将val对象推入到列表的头部或尾部
listTypePush(subject,val,where);
//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]);
//发送事件通知
notifyKeyspaceEvent(NOTIFY_LIST,event,c->argv[1],c->db->id);
server.dirty++; //更新脏键
}
//将插入val后的列表的元素个数发送给client
addReplyLongLong(c,listTypeLength(subject));
}
void ltrimCommand(redisClient *c) {
robj *o;
long start, end, llen, j, ltrim, rtrim;
list *list;
listNode *ln;
int slotnum = keyHashSlot(c->argv[1]->ptr, sdslen(c->argv[1]->ptr));
if ((getLongFromObjectOrReply(c, c->argv[2], &start, NULL) != REDIS_OK) ||
(getLongFromObjectOrReply(c, c->argv[3], &end, NULL) != REDIS_OK)) return;
if ((o = lookupKeyWriteOrReply(c,c->argv[1],shared.ok,slotnum)) == NULL ||
checkType(c,o,REDIS_LIST)) return;
llen = listTypeLength(o);
/* convert negative indexes */
if (start < 0) start = llen+start;
if (end < 0) end = llen+end;
if (start < 0) start = 0;
/* Invariant: start >= 0, so this test will be true when end < 0.
* The range is empty when start > end or start >= length. */
if (start > end || start >= llen) {
/* Out of range start or start > end result in empty list */
ltrim = llen;
rtrim = 0;
} else {
if (end >= llen) end = llen-1;
ltrim = start;
rtrim = llen-end-1;
}
/* Remove list elements to perform the trim */
if (o->encoding == REDIS_ENCODING_ZIPLIST) {
o->ptr = ziplistDeleteRange(o->ptr,0,ltrim);
o->ptr = ziplistDeleteRange(o->ptr,-rtrim,rtrim);
} else if (o->encoding == REDIS_ENCODING_LINKEDLIST) {
list = o->ptr;
for (j = 0; j < ltrim; j++) {
ln = listFirst(list);
listDelNode(list,ln);
}
for (j = 0; j < rtrim; j++) {
ln = listLast(list);
listDelNode(list,ln);
}
} else {
redisPanic("Unknown list encoding");
}
notifyKeyspaceEvent(REDIS_NOTIFY_LIST,"ltrim",c->argv[1],c->db->id);
if (listTypeLength(o) == 0) {
dbDelete(c->db,c->argv[1],slotnum);
notifyKeyspaceEvent(REDIS_NOTIFY_GENERIC,"del",c->argv[1],c->db->id);
}
signalModifiedKey(c->db,c->argv[1],slotnum);
server.dirty++;
addReply(c,shared.ok);
}
/* 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);
}
void pushxGenericCommand(redisClient *c, robj *refval, robj *val, int where) {
robj *subject;
listTypeIterator *iter;
listTypeEntry entry;
int inserted = 0;
int slotnum = keyHashSlot(c->argv[1]->ptr, sdslen(c->argv[1]->ptr));
if ((subject = lookupKeyReadOrReply(c,c->argv[1],shared.czero)) == NULL ||
checkType(c,subject,REDIS_LIST)) return;
if (refval != NULL) {
/* We're not sure if this value can be inserted yet, but we cannot
* convert the list inside the iterator. We don't want to loop over
* the list twice (once to see if the value can be inserted and once
* to do the actual insert), so we assume this value can be inserted
* and convert the ziplist to a regular list if necessary. */
listTypeTryConversion(subject,val);
/* Seek refval from head to tail */
iter = listTypeInitIterator(subject,0,REDIS_TAIL);
while (listTypeNext(iter,&entry)) {
if (listTypeEqual(&entry,refval)) {
listTypeInsert(&entry,val,where);
inserted = 1;
break;
}
}
listTypeReleaseIterator(iter);
if (inserted) {
/* Check if the length exceeds the ziplist length threshold. */
if (subject->encoding == REDIS_ENCODING_ZIPLIST &&
ziplistLen(subject->ptr) > server.list_max_ziplist_entries)
listTypeConvert(subject,REDIS_ENCODING_LINKEDLIST);
signalModifiedKey(c->db,c->argv[1],slotnum);
notifyKeyspaceEvent(REDIS_NOTIFY_LIST,"linsert",
c->argv[1],c->db->id);
server.dirty++;
} else {
/* Notify client of a failed insert */
addReply(c,shared.cnegone);
return;
}
} else {
char *event = (where == REDIS_HEAD) ? "lpush" : "rpush";
listTypePush(subject,val,where);
signalModifiedKey(c->db,c->argv[1],slotnum);
notifyKeyspaceEvent(REDIS_NOTIFY_LIST,event,c->argv[1],c->db->id);
server.dirty++;
}
addReplyLongLong(c,listTypeLength(subject));
}
void smoveCommand(client *c) {
robj *srcset, *dstset, *ele;
srcset = lookupKeyWrite(c->db,c->argv[1]);
dstset = lookupKeyWrite(c->db,c->argv[2]);
ele = c->argv[3];
/* If the source key does not exist return 0 */
if (srcset == NULL) {
addReply(c,shared.czero);
return;
}
/* If the source key has the wrong type, or the destination key
* is set and has the wrong type, return with an error. */
if (checkType(c,srcset,OBJ_SET) ||
(dstset && checkType(c,dstset,OBJ_SET))) return;
/* If srcset and dstset are equal, SMOVE is a no-op */
if (srcset == dstset) {
addReply(c,setTypeIsMember(srcset,ele->ptr) ?
shared.cone : shared.czero);
return;
}
/* If the element cannot be removed from the src set, return 0. */
if (!setTypeRemove(srcset,ele->ptr)) {
addReply(c,shared.czero);
return;
}
notifyKeyspaceEvent(NOTIFY_SET,"srem",c->argv[1],c->db->id);
/* Remove the src set from the database when empty */
if (setTypeSize(srcset) == 0) {
dbDelete(c->db,c->argv[1]);
notifyKeyspaceEvent(NOTIFY_GENERIC,"del",c->argv[1],c->db->id);
}
/* Create the destination set when it doesn't exist */
if (!dstset) {
dstset = setTypeCreate(ele->ptr);
dbAdd(c->db,c->argv[2],dstset);
}
signalModifiedKey(c->db,c->argv[1]);
signalModifiedKey(c->db,c->argv[2]);
server.dirty++;
/* An extra key has changed when ele was successfully added to dstset */
if (setTypeAdd(dstset,ele->ptr)) {
server.dirty++;
notifyKeyspaceEvent(NOTIFY_SET,"sadd",c->argv[2],c->db->id);
}
addReply(c,shared.cone);
}
void spopCommand(client *c) {
robj *set, *ele, *aux;
sds sdsele;
int64_t llele;
int encoding;
if (c->argc == 3) {
spopWithCountCommand(c);
return;
} else if (c->argc > 3) {
addReply(c,shared.syntaxerr);
return;
}
/* Make sure a key with the name inputted exists, and that it's type is
* indeed a set */
if ((set = lookupKeyWriteOrReply(c,c->argv[1],shared.nullbulk)) == NULL ||
checkType(c,set,OBJ_SET)) return;
/* Get a random element from the set */
encoding = setTypeRandomElement(set,&sdsele,&llele);
/* Remove the element from the set */
if (encoding == OBJ_ENCODING_INTSET) {
ele = createStringObjectFromLongLong(llele);
set->ptr = intsetRemove(set->ptr,llele,NULL);
} else {
ele = createStringObject(sdsele,sdslen(sdsele));
setTypeRemove(set,ele->ptr);
}
notifyKeyspaceEvent(NOTIFY_SET,"spop",c->argv[1],c->db->id);
/* Replicate/AOF this command as an SREM operation */
aux = createStringObject("SREM",4);
rewriteClientCommandVector(c,3,aux,c->argv[1],ele);
decrRefCount(aux);
/* Add the element to the reply */
addReplyBulk(c,ele);
decrRefCount(ele);
/* Delete the set if it's empty */
if (setTypeSize(set) == 0) {
dbDelete(c->db,c->argv[1]);
notifyKeyspaceEvent(NOTIFY_GENERIC,"del",c->argv[1],c->db->id);
}
/* Set has been modified */
signalModifiedKey(c->db,c->argv[1]);
server.dirty++;
}
/*SMOVE source destination member*/
void smoveCommand(redisClient *c) {//将member元素从source集合移动到destination集合
robj *srcset, *dstset, *ele;
srcset = lookupKeyWrite(c->db,c->argv[1]);
dstset = lookupKeyWrite(c->db,c->argv[2]);
ele = c->argv[3] = tryObjectEncoding(c->argv[3]);
/* If the source key does not exist return 0 */
if (srcset == NULL) {
addReply(c,shared.czero);
return;
}
/* If the source key has the wrong type, or the destination key
* is set and has the wrong type, return with an error. */
if (checkType(c,srcset,REDIS_SET) ||
(dstset && checkType(c,dstset,REDIS_SET))) return;
/* If srcset and dstset are equal, SMOVE is a no-op */
if (srcset == dstset) {
addReply(c,shared.cone);
return;
}
/* If the element cannot be removed from the src set, return 0. */
if (!setTypeRemove(srcset,ele)) {//从源集合中删除member元素
addReply(c,shared.czero);
return;
}
notifyKeyspaceEvent(REDIS_NOTIFY_SET,"srem",c->argv[1],c->db->id);
/* Remove the src set from the database when empty */
if (setTypeSize(srcset) == 0) {//移除member元素后，源集合为空，删除
dbDelete(c->db,c->argv[1]);
notifyKeyspaceEvent(REDIS_NOTIFY_GENERIC,"del",c->argv[1],c->db->id);
}
signalModifiedKey(c->db,c->argv[1]);
signalModifiedKey(c->db,c->argv[2]);
server.dirty++;
/* Create the destination set when it doesn't exist */
if (!dstset) {//目标集合不存在，则新建
dstset = setTypeCreate(ele);
dbAdd(c->db,c->argv[2],dstset);
}
/* An extra key has changed when ele was successfully added to dstset */
if (setTypeAdd(dstset,ele)) {//添加member元素到目标集合
server.dirty++;
notifyKeyspaceEvent(REDIS_NOTIFY_SET,"sadd",c->argv[2],c->db->id);
}
addReply(c,shared.cone);
}
// 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 lsetCommand(client *c) {
robj *o = lookupKeyWriteOrReply(c,c->argv[1],shared.nokeyerr);
if (o == NULL || checkType(c,o,OBJ_LIST)) return;
long index;
robj *value = c->argv[3];
if ((getLongFromObjectOrReply(c, c->argv[2], &index, NULL) != C_OK))
return;
if (o->encoding == OBJ_ENCODING_QUICKLIST) {
quicklist *ql = o->ptr;
int replaced = quicklistReplaceAtIndex(ql, index,
value->ptr, sdslen(value->ptr));
if (!replaced) {
addReply(c,shared.outofrangeerr);
} else {
addReply(c,shared.ok);
signalModifiedKey(c->db,c->argv[1]);
notifyKeyspaceEvent(NOTIFY_LIST,"lset",c->argv[1],c->db->id);
server.dirty++;
}
} else {
serverPanic("Unknown list encoding");
}
}
void pushGenericCommand(redisClient *c, int where) {
int j, waiting = 0, pushed = 0;
robj *lobj = lookupKeyWrite(c->db,c->argv[1]);
int may_have_waiting_clients = (lobj == NULL);
if (lobj && lobj->type != REDIS_LIST) {//检查类型是否是list类型
addReply(c,shared.wrongtypeerr);
return;
}
if (may_have_waiting_clients) signalListAsReady(c,c->argv[1]);
for (j = 2; j < c->argc; j++) {
c->argv[j] = tryObjectEncoding(c->argv[j]);
if (!lobj) {//该键不存在 创建压缩列表
lobj = createZiplistObject();
dbAdd(c->db,c->argv[1],lobj);//该键添加到db中
}
listTypePush(lobj,c->argv[j],where);//把value添加列表中
pushed++;
}
addReplyLongLong(c, waiting + (lobj ? listTypeLength(lobj) : 0));
if (pushed) {
char *event = (where == REDIS_HEAD) ? "lpush" : "rpush";
signalModifiedKey(c->db,c->argv[1]);
notifyKeyspaceEvent(REDIS_NOTIFY_LIST,event,c->argv[1],c->db->id);//使用键空间通知
}
//改变最后一次保存的节点
server.dirty += pushed;
}
void pushGenericCommand(redisClient *c, int where) {
int j, waiting = 0, pushed = 0;
robj *lobj = lookupKeyWrite(c->db,c->argv[1]);
if (lobj && lobj->type != REDIS_LIST) {
addReply(c,shared.wrongtypeerr);
return;
}
for (j = 2; j < c->argc; j++) {
c->argv[j] = tryObjectEncoding(c->argv[j]);
if (!lobj) {
lobj = createZiplistObject();
dbAdd(c->db,c->argv[1],lobj);
}
listTypePush(lobj,c->argv[j],where);
pushed++;
}
addReplyLongLong(c, waiting + (lobj ? listTypeLength(lobj) : 0));
if (pushed) {
char *event = (where == REDIS_HEAD) ? "lpush" : "rpush";
signalModifiedKey(c->db,c->argv[1]);
notifyKeyspaceEvent(REDIS_NOTIFY_LIST,event,c->argv[1],c->db->id);
}
server.dirty += pushed;
}
void msetGenericCommand(redisClient *c, int nx) {
int j, busykeys = 0;
if ((c->argc % 2) == 0) {
addReplyError(c,"wrong number of arguments for MSET");
return;
}
/* Handle the NX flag. The MSETNX semantic is to return zero and don't
* set nothing at all if at least one already key exists. */
if (nx) {
for (j = 1; j < c->argc; j += 2) {
if (lookupKeyWrite(c->db,c->argv[j]) != NULL) {
busykeys++;
}
}
if (busykeys) {
addReply(c, shared.czero);
return;
}
}
for (j = 1; j < c->argc; j += 2) {
c->argv[j+1] = tryObjectEncoding(c->argv[j+1]);
setKey(c->db,c->argv[j],c->argv[j+1]);
notifyKeyspaceEvent(REDIS_NOTIFY_STRING,"set",c->argv[j],c->db->id);
}
server.dirty += (c->argc-1)/2;
addReply(c, nx ? shared.cone : shared.ok);
}
// LSET key index value
// LSET命令实现
void lsetCommand(client *c) {
//以写操作取出key对象的value值
robj *o = lookupKeyWriteOrReply(c,c->argv[1],shared.nokeyerr);
// 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;
long index;
robj *value = c->argv[3];
//将index参数转换为long类型的整数，保存在index中
if ((getLongFromObjectOrReply(c, c->argv[2], &index, NULL) != C_OK))
return;
//只对编码为quicklist类型的value对象操作
if (o->encoding == OBJ_ENCODING_QUICKLIST) {
quicklist *ql = o->ptr;
//将下标为index的entry替换成value对象的值
int replaced = quicklistReplaceAtIndex(ql, index,
value->ptr, sdslen(value->ptr));
if (!replaced) {
//如果替换失败，则发送下标越界错误信息
addReply(c,shared.outofrangeerr);
} else {
//替换成功，则发送ok
addReply(c,shared.ok);
//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]);
//发送"lset"时间通知
notifyKeyspaceEvent(NOTIFY_LIST,"lset",c->argv[1],c->db->id);
//更新脏键
server.dirty++;
}
} else {
serverPanic("Unknown list encoding");
}
}
void getsetCommand(redisClient *c) {
if (getGenericCommand(c) == REDIS_ERR) return;
c->argv[2] = tryObjectEncoding(c->argv[2]);
setKey(c->db,c->argv[1],c->argv[2]);
notifyKeyspaceEvent(REDIS_NOTIFY_STRING,"set",c->argv[1],c->db->id);
server.dirty++;
}
int expireIfNeeded(redisDb *db, robj *key) {
mstime_t when = getExpire(db,key);
mstime_t now;
if (when < 0) return 0; /* No expire for this key */
/* Don't expire anything while loading. It will be done later. */
if (server.loading) return 0;
/* If we are in the context of a Lua script, we claim that time is
* blocked to when the Lua script started. This way a key can expire
* only the first time it is accessed and not in the middle of the
* script execution, making propagation to slaves / AOF consistent.
* See issue #1525 on Github for more information. */
now = server.lua_caller ? server.lua_time_start : mstime();
/* If we are running in the context of a slave, return ASAP:
* the slave key expiration is controlled by the master that will
* send us synthesized DEL operations for expired keys.
*
* Still we try to return the right information to the caller,
* that is, 0 if we think the key should be still valid, 1 if
* we think the key is expired at this time. */
if (server.masterhost != NULL) return now > when;
/* Return when this key has not expired */
if (now <= when) return 0;
/* Delete the key */
server.stat_expiredkeys++;
propagateExpire(db,key);
notifyKeyspaceEvent(NOTIFY_EXPIRED,
"expired",key,db->id);
return dbDelete(db,key);
}
// t_hash.c
void hsetCommand(client *c) {
robj *o;
// create if not exist, default is ziplist
if ((o = hashTypeLookupWriteOrCreate(c,c->argv[1])) == NULL) return;
// if keylen or valuelen > hash_max_ziplist_value, then change to hashtable
// Notice: OBJ_ENCODING_HT never change back to OBJ_ENCODING_ZIPLIST
hashTypeTryConversion(o,c->argv,2,3);
hashTypeTryObjectEncoding(o,&c->argv[2], &c->argv[3]);
update = hashTypeSet(o,c->argv[2],c->argv[3]);
// if (o->encoding == OBJ_ENCODING_ZIPLIST) {
// ziplistDelete()
// ziplistInsert()
//
// if (hashTypeLength(o) > server.hash_max_ziplist_entries)
// hashTypeConvert(o, OBJ_ENCODING_HT);
// }
// else if (o->encoding == OBJ_ENCODING_HT) {
// dictReplace()
// }
// add to reply buffer
addReply(c, update ? shared.czero : shared.cone);
signalModifiedKey(c->db,c->argv[1]);
notifyKeyspaceEvent(NOTIFY_HASH,"hset",c->argv[1],c->db->id);
server.dirty++;
}
void saddCommand(redisClient *c) {
robj *set;
int j, added = 0;
set = lookupKeyWrite(c->db,c->argv[1]);
if (set == NULL) {
set = setTypeCreate(c->argv[2]);
dbAdd(c->db,c->argv[1],set);
} else {
if (set->type != REDIS_SET) {
addReply(c,shared.wrongtypeerr);
return;
}
}
for (j = 2; j < c->argc; j++) {
c->argv[j] = tryObjectEncoding(c->argv[j]);
if (setTypeAdd(set,c->argv[j])) added++;
}
if (added) {
signalModifiedKey(c->db,c->argv[1]);
notifyKeyspaceEvent(REDIS_NOTIFY_SET,"sadd",c->argv[1],c->db->id);
}
server.dirty += added;
addReplyLongLong(c,added);
}
void setrangeCommand(redisClient *c) {
robj *o;
long offset;
sds value = c->argv[3]->ptr;
if (getLongFromObjectOrReply(c,c->argv[2],&offset,NULL) != REDIS_OK)
return;
if (offset < 0) {
addReplyError(c,"offset is out of range");
return;
}
o = lookupKeyWrite(c->db,c->argv[1]);
if (o == NULL) {
/* Return 0 when setting nothing on a non-existing string */
if (sdslen(value) == 0) {
addReply(c,shared.czero);
return;
}
/* Return when the resulting string exceeds allowed size */
if (checkStringLength(c,offset+sdslen(value)) != REDIS_OK)
return;
o = createObject(REDIS_STRING,sdsempty());
dbAdd(c->db,c->argv[1],o);
} else {
size_t olen;
/* Key exists, check type */
if (checkType(c,o,REDIS_STRING))
return;
/* Return existing string length when setting nothing */
olen = stringObjectLen(o);
if (sdslen(value) == 0) {
addReplyLongLong(c,olen);
return;
}
/* Return when the resulting string exceeds allowed size */
if (checkStringLength(c,offset+sdslen(value)) != REDIS_OK)
return;
/* Create a copy when the object is shared or encoded. */
o = dbUnshareStringValue(c->db,c->argv[1],o);
}
if (sdslen(value) > 0) {
o->ptr = sdsgrowzero(o->ptr,offset+sdslen(value));
memcpy((char*)o->ptr+offset,value,sdslen(value));
signalModifiedKey(c->db,c->argv[1]);
notifyKeyspaceEvent(REDIS_NOTIFY_STRING,
"setrange",c->argv[1],c->db->id);
server.dirty++;
}
addReplyLongLong(c,sdslen(o->ptr));
}
/* This is the generic command implementation for EXPIRE, PEXPIRE, EXPIREAT
* and PEXPIREAT. Because the commad second argument may be relative or absolute
* the "basetime" argument is used to signal what the base time is (either 0
* for *AT variants of the command, or the current time for relative expires).
*
* unit is either UNIT_SECONDS or UNIT_MILLISECONDS, and is only used for
* the argv[2] parameter. The basetime is always specified in milliseconds. */
void expireGenericCommand(client *c, long long basetime, int unit) {
robj *key = c->argv[1], *param = c->argv[2];
long long when; /* unix time in milliseconds when the key will expire. */
if (getLongLongFromObjectOrReply(c, param, &when, NULL) != C_OK)
return;
if (unit == UNIT_SECONDS) when *= 1000;
when += basetime;
/* No key, return zero. */
if (lookupKeyWrite(c->db,key) == NULL) {
addReply(c,shared.czero);
return;
}
/* EXPIRE with negative TTL, or EXPIREAT with a timestamp into the past
* should never be executed as a DEL when load the AOF or in the context
* of a slave instance.
*
* Instead we take the other branch of the IF statement setting an expire
* (possibly in the past) and wait for an explicit DEL from the master. */
if (when <= mstime() && !server.loading && !server.masterhost) {
robj *aux;
serverAssertWithInfo(c,key,dbDelete(c->db,key));
server.dirty++;
/* Replicate/AOF this as an explicit DEL. */
aux = createStringObject("DEL",3);
rewriteClientCommandVector(c,2,aux,key);
decrRefCount(aux);
signalModifiedKey(c->db,key);
notifyKeyspaceEvent(NOTIFY_GENERIC,"del",key,c->db->id);
addReply(c, shared.cone);
return;
} else {
setExpire(c->db,key,when);
addReply(c,shared.cone);
signalModifiedKey(c->db,key);
notifyKeyspaceEvent(NOTIFY_GENERIC,"expire",key,c->db->id);
server.dirty++;
return;
}
}
void ltrimCommand(client *c) {
robj *o;
long start, end, llen, ltrim, rtrim;
if ((getLongFromObjectOrReply(c, c->argv[2], &start, NULL) != C_OK) ||
(getLongFromObjectOrReply(c, c->argv[3], &end, NULL) != C_OK)) return;
if ((o = lookupKeyWriteOrReply(c,c->argv[1],shared.ok)) == NULL ||
checkType(c,o,OBJ_LIST)) return;
llen = listTypeLength(o);
/* convert negative indexes */
if (start < 0) start = llen+start;
if (end < 0) end = llen+end;
if (start < 0) start = 0;
/* Invariant: start >= 0, so this test will be true when end < 0.
* The range is empty when start > end or start >= length. */
if (start > end || start >= llen) {
/* Out of range start or start > end result in empty list */
ltrim = llen;
rtrim = 0;
} else {
if (end >= llen) end = llen-1;
ltrim = start;
rtrim = llen-end-1;
}
/* Remove list elements to perform the trim */
if (o->encoding == OBJ_ENCODING_QUICKLIST) {
quicklistDelRange(o->ptr,0,ltrim);
quicklistDelRange(o->ptr,-rtrim,rtrim);
} else {
serverPanic("Unknown list encoding");
}
notifyKeyspaceEvent(NOTIFY_LIST,"ltrim",c->argv[1],c->db->id);
if (listTypeLength(o) == 0) {
dbDelete(c->db,c->argv[1]);
notifyKeyspaceEvent(NOTIFY_GENERIC,"del",c->argv[1],c->db->id);
}
signalModifiedKey(c->db,c->argv[1]);
server.dirty++;
addReply(c,shared.ok);
}
void lremCommand(client *c) {
robj *subject, *obj;
obj = c->argv[3];
long toremove;
long removed = 0;
if ((getLongFromObjectOrReply(c, c->argv[2], &toremove, NULL) != C_OK))
return;
subject = lookupKeyWriteOrReply(c,c->argv[1],shared.czero);
if (subject == NULL || checkType(c,subject,OBJ_LIST)) return;
listTypeIterator *li;
if (toremove < 0) {
toremove = -toremove;
li = listTypeInitIterator(subject,-1,LIST_HEAD);
} else {
li = listTypeInitIterator(subject,0,LIST_TAIL);
}
listTypeEntry entry;
while (listTypeNext(li,&entry)) {
if (listTypeEqual(&entry,obj)) {
listTypeDelete(li, &entry);
server.dirty++;
removed++;
if (toremove && removed == toremove) break;
}
}
listTypeReleaseIterator(li);
if (removed) {
signalModifiedKey(c->db,c->argv[1]);
notifyKeyspaceEvent(NOTIFY_GENERIC,"lrem",c->argv[1],c->db->id);
}
if (listTypeLength(subject) == 0) {
dbDelete(c->db,c->argv[1]);
notifyKeyspaceEvent(NOTIFY_GENERIC,"del",c->argv[1],c->db->id);
}
addReplyLongLong(c,removed);
}
void lsetCommand(redisClient *c) {
int slotnum = keyHashSlot(c->argv[1]->ptr, sdslen(c->argv[1]->ptr));
robj *o = lookupKeyWriteOrReply(c,c->argv[1],shared.nokeyerr,slotnum);
if (o == NULL || checkType(c,o,REDIS_LIST)) return;
long index;
robj *value = (c->argv[3] = tryObjectEncoding(c->argv[3]));
if ((getLongFromObjectOrReply(c, c->argv[2], &index, NULL) != REDIS_OK))
return;
listTypeTryConversion(o,value);
if (o->encoding == REDIS_ENCODING_ZIPLIST) {
unsigned char *p, *zl = o->ptr;
p = ziplistIndex(zl,index);
if (p == NULL) {
addReply(c,shared.outofrangeerr);
} else {
o->ptr = ziplistDelete(o->ptr,&p);
value = getDecodedObject(value);
o->ptr = ziplistInsert(o->ptr,p,value->ptr,sdslen(value->ptr));
decrRefCount(value);
addReply(c,shared.ok);
signalModifiedKey(c->db,c->argv[1],slotnum);
notifyKeyspaceEvent(REDIS_NOTIFY_LIST,"lset",c->argv[1],c->db->id);
server.dirty++;
}
} else if (o->encoding == REDIS_ENCODING_LINKEDLIST) {
listNode *ln = listIndex(o->ptr,index);
if (ln == NULL) {
addReply(c,shared.outofrangeerr);
} else {
decrRefCount((robj*)listNodeValue(ln));
listNodeValue(ln) = value;
incrRefCount(value);
addReply(c,shared.ok);
signalModifiedKey(c->db,c->argv[1],slotnum);
notifyKeyspaceEvent(REDIS_NOTIFY_LIST,"lset",c->argv[1],c->db->id);
server.dirty++;
}
} else {
redisPanic("Unknown list encoding");
}
}
void pushxGenericCommand(client *c, robj *refval, robj *val, int where) {
robj *subject;
listTypeIterator *iter;
listTypeEntry entry;
int inserted = 0;
if ((subject = lookupKeyWriteOrReply(c,c->argv[1],shared.czero)) == NULL ||
checkType(c,subject,OBJ_LIST)) return;
if (refval != NULL) {
/* Seek refval from head to tail */
iter = listTypeInitIterator(subject,0,LIST_TAIL);
while (listTypeNext(iter,&entry)) {
if (listTypeEqual(&entry,refval)) {
listTypeInsert(&entry,val,where);
inserted = 1;
break;
}
}
listTypeReleaseIterator(iter);
if (inserted) {
signalModifiedKey(c->db,c->argv[1]);
notifyKeyspaceEvent(NOTIFY_LIST,"linsert",
c->argv[1],c->db->id);
server.dirty++;
} else {
/* Notify client of a failed insert */
addReply(c,shared.cnegone);
return;
}
} else {
char *event = (where == LIST_HEAD) ? "lpush" : "rpush";
listTypePush(subject,val,where);
signalModifiedKey(c->db,c->argv[1]);
notifyKeyspaceEvent(NOTIFY_LIST,event,c->argv[1],c->db->id);
server.dirty++;
}
addReplyLongLong(c,listTypeLength(subject));
}
void renameGenericCommand(client *c, int nx) {
robj *o;
long long expire;
int samekey = 0;
/* When source and dest key is the same, no operation is performed,
* if the key exists, however we still return an error on unexisting key. */
if (sdscmp(c->argv[1]->ptr,c->argv[2]->ptr) == 0) samekey = 1;
if ((o = lookupKeyWriteOrReply(c,c->argv[1],shared.nokeyerr)) == NULL)
return;
if (samekey) {
addReply(c,nx ? shared.czero : shared.ok);
return;
}
incrRefCount(o);
expire = getExpire(c->db,c->argv[1]);
if (lookupKeyWrite(c->db,c->argv[2]) != NULL) {
if (nx) {
decrRefCount(o);
addReply(c,shared.czero);
return;
}
/* Overwrite: delete the old key before creating the new one
* with the same name. */
dbDelete(c->db,c->argv[2]);
}
dbAdd(c->db,c->argv[2],o);
if (expire != -1) setExpire(c->db,c->argv[2],expire);
dbDelete(c->db,c->argv[1]);
signalModifiedKey(c->db,c->argv[1]);
signalModifiedKey(c->db,c->argv[2]);
notifyKeyspaceEvent(NOTIFY_GENERIC,"rename_from",
c->argv[1],c->db->id);
notifyKeyspaceEvent(NOTIFY_GENERIC,"rename_to",
c->argv[2],c->db->id);
server.dirty++;
addReply(c,nx ? shared.cone : shared.ok);
}
