本文主要是介绍Redis的C客户端(hiredis库)使用，希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！
文章目录
- 1、Ubuntu安装redis服务端
- 2、hiredis库的安装
- 3、同步API接口的使用
- 3.1、连接redis数据库redisConnect
- 3.2、发送需要执行的命令redisCommand
- 3.3、redisCommandArgv函数
- 3.4、redisAppendCommand*函数支持管道命令
- 3.5、释放资源
- 3.6、同步连接代码
- 3.7、异步连接
- 4、redis连接池实现
Hiredis是一个Redis的C客户端库函数，基本实现了Redis的协议的最小集。这里对hiredis的api作基本的介绍以及应用，主要参考hiredis的README文件以及相关源码。
1、Ubuntu安装redis服务端
Redis全称为Remote Dictionary Server（远程数据服务），是一款开源的基于内存的键值对存储系统，其主要被用作高性能缓存服务器使用，当然也可以作为消息中间件和Session共享等。Redis独特的键值对模型使之支持丰富的数据结构类型，即它的值可以是字符串、哈希、列表、集合、有序集合，而不像Memcached要求的键和值都是字符串。同时由于Redis是基于内存的方式，免去了磁盘I/O速度的影响，因此其读写性能极高。
1、在Ubuntu中打开终端，输入下列命令，下载Redis安装包：
wget http://download.redis.io/releases/redis-4.0.9.tar.gz
2、对安装包进行解压，并将其移动放到usr/local⽬录下
命令如下：
解压：
tar xzf redis-4.0.9.tar.gz
移动到
sudo mv ./redis-4.0.9 /usr/local/redis/
3、进入redis⽬录，编译生成
命令：
cd /usr/local/redis/
sudo make测试
sudo make test
4、安装,将redis的命令安装到/usr/local/bin/⽬录
sudo make install
5、安装完成后，我们进入目录/usr/local/bin中查看
cd /usr/local/bin
ls -all
6、配置⽂件，移动到/etc/⽬录下
配置⽂件⽬录为/usr/local/redis/redis.conf
sudo cp /usr/local/redis/redis.conf /etc/redis/
7、Redis的配置信息在/etc/redis/redis.conf下
sudo vi /etc/redis/redis.conf绑定ip：如果需要远程访问，可将此⾏注释，或绑定⼀个真实ip
bind 127.0.0.1端⼝，默认为6379
port 6379是否以守护进程运⾏
如果以守护进程运⾏，则不会在命令⾏阻塞，类似于服务
如果以⾮守护进程运⾏，则当前终端被阻塞
设置为yes表示守护进程，设置为no表示⾮守护进程
推荐设置为yes
daemonize yes数据⽂件
dbfilename dump.rdb数据⽂件存储路径
dir /var/lib/redis⽇志⽂件
logfile "/var/log/redis/redis-server.log"数据库，默认有16个
database 16主从复制，类似于双机备份。
slaveof
连接服务端
./redis-cli -h 127.0.0.1 -p 6379
2、hiredis库的安装
官网：https://redislabs.com/lp/hiredis/
发行版本：https://github.com/redis/hiredis/releases
目前最新的版本：https://codeload.github.com/redis/hiredis/tar.gz/v0.14.0
1、解压：tar -zxvf hiredis-0.14.0.tar.gz
2、编译：make
3、安装：make install
也可以直接将文件编译到自己的工程代码。
3、同步API接口的使用
我们的项目中使用的hireds接口都是同步的API，所谓同步意思就是使用阻塞的方式向redis server下发消息。
接口的主要部分为下面三个部分，下面分别介绍。
/**连接数据库*/
redisContext *redisConnect(const char *ip, int port);
/**发送命令请求*/
void *redisCommand(redisContext *c, const char *format, ...);
void *redisCommandArgv(redisContext *c, int argc, const char **argv, const size_t *argvlen);
void redisAppendCommand(redisContext *c, const char *format, ...);
void redisAppendCommandArgv(redisContext *c, int argc, const char **argv, const size_t *argvlen);
/*释放资源*/
void freeReplyObject(void *reply);
void redisFree(redisContext *c);
3.1、连接redis数据库redisConnect
redisContext *redisConnect(const char *ip, int port);
参数说明
● port：为redis数据监听的端口号，redis默认监听的端口号为6379
● ip：为redis数据库的IP地址，可以是远程的，也可以是本地的127.0.0.1
返回值
返回值是一个指向redisContext对象，可以不用了解这个对象的具体组成部分，只需要知道怎么使用就可以了。下面是其定义。
typedef struct redisContext {int err; /* Error flags, 0 when there is no error */char errstr[128]; /* String representation of error when applicable */int fd;int flags;char *obuf; /* Write buffer */redisReader *reader; /* Protocol reader */enum redisConnectionType connection_type;struct timeval *timeout;struct {char *host;char *source_addr;int port;} tcp;struct {char *path;} unix_sock;
} redisContext;
3.2、发送需要执行的命令redisCommand
void *redisCommand(redisContext *c, const char *format, ...);
参数说明
这个函数是一个带有不定参数的。可以按着format格式给出对应的参数，这就和printf函数类似。
c 是一个reidsConnect函数返回的一个对象。
返回值
返回值是一个void类型的指针，实际为指向一个redisReply类型的指针。
/* This is the reply object returned by redisCommand() */
typedef struct redisReply {/*命令执行结果的返回类型*/int type; /* REDIS_REPLY_* *//*存储执行结果返回为整数*/long long integer; /* The integer when type is REDIS_REPLY_INTEGER *//*字符串值的长度*/size_t len; /* Length of string *//*存储命令执行结果返回是字符串*/char *str; /* Used for both REDIS_REPLY_ERROR and REDIS_REPLY_STRING *//*返回结果是数组的大小*/size_t elements; /* number of elements, for REDIS_REPLY_ARRAY *//*存储执行结果返回是数组*/struct redisReply **element; /* elements vector for REDIS_REPLY_ARRAY */
} redisReply;返回结果的类型reply->type,reply 为redisReply* 类型。
● REDIS_REPLY_STRING == 1:返回值是字符串,字符串储存在redis->str当中,字符串长度为redis->len。
● REDIS_REPLY_ARRAY == 2：返回值是数组，数组大小存在redis->elements里面，数组值存储在redis->element[i]里面。数组里面存储的是指向redisReply的指针，数组里面的返回值可以通过redis->element[i]->str来访问，数组的结果里全是type==REDIS_REPLY_STRING的redisReply对象指针。
● REDIS_REPLY_INTEGER == 3：返回值为整数 long long。
● REDIS_REPLY_NIL==4：返回值为空表示执行结果为空。
● REDIS_REPLY_STATUS ==5：返回命令执行的状态，比如set foo bar 返回的状态为OK，存储在str当中 reply->str == "OK"。
● REDIS_REPLY_ERROR ==6 ：命令执行错误,错误信息存放在 reply->str当中。
3.3、redisCommandArgv函数
void *redisCommandArgv(redisContext *c, int argc, const char **argv, const size_t *argvlen);
参数说明
argvlen这个数组存储了命令参数中，每一个参数的长度，包含命令本身，比如 set foo bar 则argvlen ={3,3,3},如果argvlen为空，那么这个函数内部会自动调用strlen函数对每个参数进行求长度。
argv 存放每个命令参数的指针，argv={“set”,“foo”,“bar”}
argc 存放命令参数的个数上面的例子中argc=3
c 为redisContext对象。
为每一个参数指定长度，可以是二进制安全的函数。函数会按着长度来决定字符串的终止，而不是’\0’.
char hkey[] = "123456";
char hset[] = "hset";
char key[] = "testkey";
char hvalue[] = "3210";
int argc = 4;
char *argv[] = {hset,key,hkey,hvalue};
size_t argvlen[] = {4,6,4,3};
redisCommandArgv(context,argc,argv,argvlen);
hgetall testkey
会得到321并不会得到和hvalue一样的值"3210"，因为在hset命令中指定了长度，只会读取前面的三个字符。
3.4、redisAppendCommand*函数支持管道命令
void redisAppendCommand(redisContext *c, const char *format, ...);
void redisAppendCommandArgv(redisContext *c, int argc, const char **argv, const size_t *argvlen);
int redisGetReply(redisContext *context,redisReply** reply);
参数说明：
redisAppendCommand函数和redisCommand函数参数一致，format可以指定特定参数的类型。
c 为redisContext对象
redisAppendCommandArgv函数和redisCommandArgv函数类似，参数含义也相同。
redisGetReply函数用来获得执行的结果的一条返回，并存储在reply所指的对象当中。成功返回REDIS_OK,否则返回REIDS_ERR。多条命令的一次性返回结果都存放在redisContext里面。
所不同的是，这个两个命令的结果。这两个函数是把多个命令存放在缓冲区内，然后一起发送给redis服务器，一次执行。可以通过redisGetReply函数从
redisContext中取出返回的结果。
使用例子：
redisReply *reply;
/*添加命令set */
redisAppendCommand(context,"SET foo bar");
/*添加命令get */
redisAppendCommand(context,"GET foo");
/*获取set命令结果*/
redisGetReply(context,&reply); // reply for SET
freeReplyObject(reply);
/*获取get命令结果*/
redisGetReply(context,&reply); // reply for GET
freeReplyObject(reply);
3.5、释放资源
void freeReplyObject(void *reply);
void redisFree(redisContext *c);
参数说明
freeReplyObject函数中reply 实际为指向redisReply结构体的指针，可能是redisCommand的返回值，后续可以看到以也能是管道命令执行结果的返回值。
redisFree函数中c实际为指向redisContext对象，这个函数会清理连接资源并释放连接。
3.6、同步连接代码
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include "hiredis/hiredis.h"int main(int argc,char *argv[])
{unsigned int j,isunix = 0;redisContext *c;redisReply *reply;const char *hostname = "127.0.0.1";int port = 6379;struct timeval timeout = {1,500000}; // 1.5 secondsc = redisConnectWithTimeout(hostname,port,timeout);if(c == NULL || c->err){if(c){printf("Connection error:%s\n",c->errstr);redisFree(c);} else {printf("Connection error:can't allocate redis context\n");}exit(1);}int num = 1000;for(int i=0;i<num;i++){// INCR counter 是 Redis 的一个命令，它用于将名为 "counter" 的键的值递增1。如果该键不存在，它将被创建并初始化为0reply = redisCommand(c,"INCR counter");printf("INCR counter:%lld\n",reply->integer);freeReplyObject(reply);}redisFree(c);return 0;
}
如果执行的时候报这个错误
解决办法：
确保你的/etc/ld.so.conf里面有 /usr/local/lib 这一行
没有的话vim编辑在尾行加上
然后 sudo ldconfig
2、 ldconfig介绍
ldconfig是一个动态链接库管理命令，其目的为了让动态链接库为系统所共享。
当进程需要链接相应的库文件时候，会默认搜寻/lilb和/usr/lib，以及配置文件/etc/ld.so.conf内所列的目录下的库文件。若找不到的话，就会出现如上图的错误。
ldconfig通常在系统启动时运行，而当用户安装了一个新的动态链接库时，就需要手工运行这个命令。
ldconfig需要注意的地方：
往/lib和/usr/lib里面加东西，是不用修改/etc/ld.so.conf文件的，但是添加完后需要调用下ldconfig，不然添加的library会找不到。如果添加的library不在/lib和/usr/lib里面的话，就一定要修改/etc/ld.so.conf文件，往该文件追加library所在的路径，然后也需要重新调用下ldconfig命令。比如在安装MySQL的时候，其库文件/usr/local/mysql/lib，就需要追加到/etc/ld.so.conf文件中。命令如下：echo "/usr/local/mysql/lib" >> /etc/ld.so.confldconfig -v | grep mysql最后注意：
如果添加的library不在/lib或/usr/lib下，但是却没有权限操作写/etc/ld.so.conf文件的话，这时就需要往export里写一个全局变量LD_LIBRARY_PATH，就可以了。
3.7、异步连接
#include "hiredis/hiredis.h"
#include "hiredis/async.h"
#include "reactor.h"
#include "adapter.h"
#include <time.h>static reactor_t *R;
static int cnt, before, num;int current_tick() {int t = 0;struct timespec ti;clock_gettime(CLOCK_MONOTONIC, &ti);t = (int)ti.tv_sec * 1000;t += ti.tv_nsec / 1000000;return t;
}void getCallback(redisAsyncContext *c, void *r, void *privdata) {redisReply *reply = r;if (reply == NULL) return;printf("argv[%s]: %lld\n", (char*)privdata, reply->integer);/* Disconnect after receiving the reply to GET */cnt++;if (cnt == num) {int used = current_tick()-before;printf("after %d exec redis command, used %d ms\n", num, used);redisAsyncDisconnect(c);}
}void connectCallback(const redisAsyncContext *c, int status) {if (status != REDIS_OK) {printf("Error: %s\n", c->errstr);stop_eventloop(R);return;}printf("Connected...\n");
}void disconnectCallback(const redisAsyncContext *c, int status) {if (status != REDIS_OK) {printf("Error: %s\n", c->errstr);stop_eventloop(R);return;}printf("Disconnected...\n");stop_eventloop(R);
}int main(int argc, char **argv) {redisAsyncContext *c = redisAsyncConnect("127.0.0.1", 6379);if (c->err) {/* Let *c leak for now... */printf("Error: %s\n", c->errstr);return 1;}R = create_reactor();redisAttach(R, c);redisAsyncSetConnectCallback(c, connectCallback);redisAsyncSetDisconnectCallback(c, disconnectCallback);before = current_tick();num = (argc > 1) ? atoi(argv[1]) : 1000;for (int i = 0; i < num; i++) {redisAsyncCommand(c, getCallback, "count", "INCR counter");}eventloop(R);release_reactor(R);return 0;
}// gcc main.c -o main -L./hiredis -lhiredis4、redis连接池实现
1、Thread.h头文件
#ifndef __THREAD_H__
#define __THREAD_H__
#include <stdint.h>
#include <pthread.h>class CThreadNotify
{
public:CThreadNotify(){pthread_mutexattr_init(&m_mutexattr);pthread_mutexattr_settype(&m_mutexattr, PTHREAD_MUTEX_RECURSIVE);pthread_mutex_init(&m_mutex, &m_mutexattr);pthread_cond_init(&m_cond, NULL);}~CThreadNotify(){pthread_mutexattr_destroy(&m_mutexattr);pthread_mutex_destroy(&m_mutex);pthread_cond_destroy(&m_cond);}void Lock(){pthread_mutex_lock(&m_mutex);}void Unlock(){pthread_mutex_unlock(&m_mutex);}void Wait(){pthread_cond_wait(&m_cond, &m_mutex);}// 返回0则正常，其他值为异常int WaitTime(int ms){//获取时间struct timespec outtime;clock_gettime(CLOCK_MONOTONIC, &outtime);//ms为毫秒，换算成秒outtime.tv_sec += ms / 1000;//在outtime的基础上，增加ms毫秒//outtime.tv_nsec为纳秒，1微秒=1000纳秒//tv_nsec此值再加上剩余的毫秒数 ms%1000，有可能超过1秒。需要特殊处理uint64_t us = outtime.tv_nsec / 1000 + 1000 * (ms % 1000); //微秒//us的值有可能超过1秒，outtime.tv_sec += us / 1000000;us = us % 1000000;outtime.tv_nsec = us * 1000; //换算成纳秒return pthread_cond_timedwait(&m_cond, &m_mutex, &outtime);}void Signal(){pthread_cond_signal(&m_cond);}private:pthread_mutex_t m_mutex;pthread_mutexattr_t m_mutexattr;pthread_cond_t m_cond;
};#endif2、头文件CachePool.h
/** @Author: your name* @Date: 2019-12-07 10:54:57* @LastEditTime : 2020-01-10 16:35:13* @LastEditors : Please set LastEditors* @Description: In User Settings Edit* @FilePath: \src\cache_pool\CachePool.h*/
#ifndef CACHEPOOL_H_
#define CACHEPOOL_H_#include <iostream>
#include <vector>
#include <map>
#include <list>#include "Thread.h"#include "hiredis.h"using std::string;
using std::list;
using std::map;
using std::vector; class CachePool;class CacheConn {
public:CacheConn(const char* server_ip, int server_port, int db_index, const char* password, const char *pool_name ="");CacheConn(CachePool* pCachePool); virtual ~CacheConn();int Init();void DeInit();const char* GetPoolName();// 通用操作// 判断一个key是否存在bool isExists(string &key);// 删除某个keylong del(string &key);// ------------------- 字符串相关 -------------------string get(string key);string set(string key, string& value);string setex(string key, int timeout, string value);// string mset(string key, map);//批量获取bool mget(const vector<string>& keys, map<string, string>& ret_value);//原子加减1long incr(string key);long decr(string key);// ---------------- 哈希相关 ------------------------long hdel(string key, string field);string hget(string key, string field);bool hgetAll(string key, map<string, string>& ret_value);long hset(string key, string field, string value);long hincrBy(string key, string field, long value);long incrBy(string key, long value);string hmset(string key, map<string, string>& hash);bool hmget(string key, list<string>& fields, list<string>& ret_value);// ------------ 链表相关 ------------long lpush(string key, string value);long rpush(string key, string value);long llen(string key);bool lrange(string key, long start, long end, list<string>& ret_value);bool flushdb();private:CachePool* m_pCachePool;redisContext* m_pContext;uint64_t m_last_connect_time;uint16_t m_server_port;string m_server_ip;string m_password;uint16_t m_db_index;string m_pool_name;
};class CachePool {
public:// db_index和mysql不同的地方 CachePool(const char* pool_name, const char* server_ip, int server_port, int db_index, const char *password, int max_conn_cnt);virtual ~CachePool();int Init();// 获取空闲的连接资源CacheConn* GetCacheConn();// Pool回收连接资源void RelCacheConn(CacheConn* pCacheConn);const char* GetPoolName() { return m_pool_name.c_str(); }const char* GetServerIP() { return m_server_ip.c_str(); }const char* GetPassword() { return m_password.c_str(); }int GetServerPort() { return m_server_port; }int GetDBIndex() { return m_db_index; }
private:string m_pool_name;string m_server_ip;string m_password;int m_server_port;int m_db_index; // mysql 数据库名字， redis db indexint m_cur_conn_cnt;int m_max_conn_cnt;list<CacheConn*> m_free_list;CThreadNotify m_free_notify;
};#endif /* CACHEPOOL_H_ */3、CachePool.cpp文件
#include "CachePool.h"#include <stdlib.h>
#include <string.h>
#include "Thread.h"#define log_error printf
#define log_info printf#define MIN_CACHE_CONN_CNT 2
#define MAX_CACHE_CONN_FAIL_NUM 10CacheConn::CacheConn(const char *server_ip, int server_port, int db_index, const char *password,const char *pool_name)
{m_server_ip = server_ip;m_server_port = server_port;m_db_index = db_index;m_password = password;m_pool_name = pool_name;m_pContext = NULL;m_last_connect_time = 0;
}CacheConn::CacheConn(CachePool *pCachePool)
{m_pCachePool = pCachePool;if (pCachePool){m_server_ip = pCachePool->GetServerIP();m_server_port = pCachePool->GetServerPort();m_db_index = pCachePool->GetDBIndex();m_password = pCachePool->GetPassword();m_pool_name = pCachePool->GetPoolName();}else{log_error("pCachePool is NULL\n");}m_pContext = NULL;m_last_connect_time = 0;
}CacheConn::~CacheConn()
{if (m_pContext){redisFree(m_pContext);m_pContext = NULL;}
}/** redis初始化连接和重连操作，类似mysql_ping()*/
int CacheConn::Init()
{if (m_pContext) // 非空，连接是正常的{return 0;}// 1s 尝试重连一次uint64_t cur_time = (uint64_t)time(NULL);if (cur_time < m_last_connect_time + 1) // 重连尝试 间隔1秒 {printf("cur_time:%lu, m_last_connect_time:%lu\n", cur_time, m_last_connect_time);return 1;}// printf("m_last_connect_time = cur_time\n");m_last_connect_time = cur_time;// 1000ms超时struct timeval timeout = {0, 1000000};// 建立连接后使用 redisContext 来保存连接状态。// redisContext 在每次操作后会修改其中的 err 和 errstr 字段来表示发生的错误码（大于0）和对应的描述。m_pContext = redisConnectWithTimeout(m_server_ip.c_str(), m_server_port, timeout);if (!m_pContext || m_pContext->err){if (m_pContext){log_error("redisConnect failed: %s\n", m_pContext->errstr);redisFree(m_pContext);m_pContext = NULL;}else{log_error("redisConnect failed\n");}return 1;}redisReply *reply;// 验证if (!m_password.empty()){reply = (redisReply *)redisCommand(m_pContext, "AUTH %s", m_password.c_str());if (!reply || reply->type == REDIS_REPLY_ERROR){log_error("Authentication failure:%p\n", reply);if (reply)freeReplyObject(reply);return -1;}else{// log_info("Authentication success\n");}freeReplyObject(reply);}reply = (redisReply *)redisCommand(m_pContext, "SELECT %d", 0);if (reply && (reply->type == REDIS_REPLY_STATUS) && (strncmp(reply->str, "OK", 2) == 0)){freeReplyObject(reply);return 0;}else{if (reply)log_error("select cache db failed:%s\n", reply->str);return 2;}
}void CacheConn::DeInit()
{if (m_pContext){redisFree(m_pContext);m_pContext = NULL;}
}const char *CacheConn::GetPoolName()
{return m_pool_name.c_str();
}string CacheConn::get(string key)
{string value;if (Init()){return value;}redisReply *reply = (redisReply *)redisCommand(m_pContext, "GET %s", key.c_str());if (!reply){log_error("redisCommand failed:%s\n", m_pContext->errstr);redisFree(m_pContext);m_pContext = NULL;return value;}if (reply->type == REDIS_REPLY_STRING){value.append(reply->str, reply->len);}freeReplyObject(reply);return value;
}string CacheConn::set(string key, string &value)
{string ret_value;if (Init()){return ret_value;}// 返回的结果存放在redisReplyredisReply *reply = (redisReply *)redisCommand(m_pContext, "SET %s %s", key.c_str(), value.c_str());if (!reply){log_error("redisCommand failed:%s\n", m_pContext->errstr);redisFree(m_pContext);m_pContext = NULL;return ret_value;}ret_value.append(reply->str, reply->len);freeReplyObject(reply); // 释放资源return ret_value;
}string CacheConn::setex(string key, int timeout, string value)
{string ret_value;if (Init()){return ret_value;}redisReply *reply = (redisReply *)redisCommand(m_pContext, "SETEX %s %d %s", key.c_str(), timeout, value.c_str());if (!reply){log_error("redisCommand failed:%s\n", m_pContext->errstr);redisFree(m_pContext);m_pContext = NULL;return ret_value;}ret_value.append(reply->str, reply->len);freeReplyObject(reply);return ret_value;
}bool CacheConn::mget(const vector<string> &keys, map<string, string> &ret_value)
{if (Init()){return false;}if (keys.empty()){return false;}string strKey;bool bFirst = true;for (vector<string>::const_iterator it = keys.begin(); it != keys.end(); ++it){if (bFirst){bFirst = false;strKey = *it;}else{strKey += " " + *it;}}if (strKey.empty()){return false;}strKey = "MGET " + strKey;redisReply *reply = (redisReply *)redisCommand(m_pContext, strKey.c_str());if (!reply){log_info("redisCommand failed:%s\n", m_pContext->errstr);redisFree(m_pContext);m_pContext = NULL;return false;}if (reply->type == REDIS_REPLY_ARRAY){for (size_t i = 0; i < reply->elements; ++i){redisReply *child_reply = reply->element[i];if (child_reply->type == REDIS_REPLY_STRING){ret_value[keys[i]] = child_reply->str;}}}freeReplyObject(reply);return true;
}bool CacheConn::isExists(string &key)
{if (Init()){return false;}redisReply *reply = (redisReply *)redisCommand(m_pContext, "EXISTS %s", key.c_str());if (!reply){log_error("redisCommand failed:%s\n", m_pContext->errstr);redisFree(m_pContext);m_pContext = NULL;return false;}long ret_value = reply->integer;freeReplyObject(reply);if (0 == ret_value){return false;}else{return true;}
}long CacheConn::del(string &key)
{if (Init()){return 0;}redisReply *reply = (redisReply *)redisCommand(m_pContext, "DEL %s", key.c_str());if (!reply){log_error("redisCommand failed:%s\n", m_pContext->errstr);redisFree(m_pContext);m_pContext = NULL;return 0;}long ret_value = reply->integer;freeReplyObject(reply);return ret_value;
}long CacheConn::hdel(string key, string field)
{if (Init()){return 0;}redisReply *reply = (redisReply *)redisCommand(m_pContext, "HDEL %s %s", key.c_str(), field.c_str());if (!reply){log_error("redisCommand failed:%s\n", m_pContext->errstr);redisFree(m_pContext);m_pContext = NULL;return 0;}long ret_value = reply->integer;freeReplyObject(reply);return ret_value;
}string CacheConn::hget(string key, string field)
{string ret_value;if (Init()){return ret_value;}redisReply *reply = (redisReply *)redisCommand(m_pContext, "HGET %s %s", key.c_str(), field.c_str());if (!reply){log_error("redisCommand failed:%s\n", m_pContext->errstr);redisFree(m_pContext);m_pContext = NULL;return ret_value;}if (reply->type == REDIS_REPLY_STRING){ret_value.append(reply->str, reply->len);}freeReplyObject(reply);return ret_value;
}bool CacheConn::hgetAll(string key, map<string, string> &ret_value)
{if (Init()){return false;}redisReply *reply = (redisReply *)redisCommand(m_pContext, "HGETALL %s", key.c_str());if (!reply){log_error("redisCommand failed:%s\n", m_pContext->errstr);redisFree(m_pContext);m_pContext = NULL;return false;}if ((reply->type == REDIS_REPLY_ARRAY) && (reply->elements % 2 == 0)){for (size_t i = 0; i < reply->elements; i += 2){redisReply *field_reply = reply->element[i];redisReply *value_reply = reply->element[i + 1];string field(field_reply->str, field_reply->len);string value(value_reply->str, value_reply->len);ret_value.insert(make_pair(field, value));}}freeReplyObject(reply);return true;
}long CacheConn::hset(string key, string field, string value)
{if (Init()){return -1;}redisReply *reply = (redisReply *)redisCommand(m_pContext, "HSET %s %s %s", key.c_str(), field.c_str(), value.c_str());if (!reply){log_error("redisCommand failed:%s\n", m_pContext->errstr);redisFree(m_pContext);m_pContext = NULL;return -1;}long ret_value = reply->integer;freeReplyObject(reply);return ret_value;
}long CacheConn::hincrBy(string key, string field, long value)
{if (Init()){return -1;}redisReply *reply = (redisReply *)redisCommand(m_pContext, "HINCRBY %s %s %ld", key.c_str(), field.c_str(), value);if (!reply){log_error("redisCommand failed:%s\n", m_pContext->errstr);redisFree(m_pContext);m_pContext = NULL;return -1;}long ret_value = reply->integer;freeReplyObject(reply);return ret_value;
}long CacheConn::incrBy(string key, long value)
{if (Init()){return -1;}redisReply *reply = (redisReply *)redisCommand(m_pContext, "INCRBY %s %ld", key.c_str(), value);if (!reply){log_error("redis Command failed:%s\n", m_pContext->errstr);redisFree(m_pContext);m_pContext = NULL;return -1;}long ret_value = reply->integer;freeReplyObject(reply);return ret_value;
}string CacheConn::hmset(string key, map<string, string> &hash)
{string ret_value;if (Init()){return ret_value;}int argc = hash.size() * 2 + 2;const char **argv = new const char *[argc];if (!argv){return ret_value;}argv[0] = "HMSET";argv[1] = key.c_str();int i = 2;for (map<string, string>::iterator it = hash.begin(); it != hash.end(); it++){argv[i++] = it->first.c_str();argv[i++] = it->second.c_str();}redisReply *reply = (redisReply *)redisCommandArgv(m_pContext, argc, argv, NULL);if (!reply){log_error("redisCommand failed:%s\n", m_pContext->errstr);delete[] argv;redisFree(m_pContext);m_pContext = NULL;return ret_value;}ret_value.append(reply->str, reply->len);delete[] argv;freeReplyObject(reply);return ret_value;
}bool CacheConn::hmget(string key, list<string> &fields, list<string> &ret_value)
{if (Init()){return false;}int argc = fields.size() + 2;const char **argv = new const char *[argc];if (!argv){return false;}argv[0] = "HMGET";argv[1] = key.c_str();int i = 2;for (list<string>::iterator it = fields.begin(); it != fields.end(); it++){argv[i++] = it->c_str();}redisReply *reply = (redisReply *)redisCommandArgv(m_pContext, argc, (const char **)argv, NULL);if (!reply){log_error("redisCommand failed:%s\n", m_pContext->errstr);delete[] argv;redisFree(m_pContext);m_pContext = NULL;return false;}if (reply->type == REDIS_REPLY_ARRAY){for (size_t i = 0; i < reply->elements; i++){redisReply *value_reply = reply->element[i];string value(value_reply->str, value_reply->len);ret_value.push_back(value);}}delete[] argv;freeReplyObject(reply);return true;
}long CacheConn::incr(string key)
{if (Init()){return -1;}redisReply *reply = (redisReply *)redisCommand(m_pContext, "INCR %s", key.c_str());if (!reply){log_error("redis Command failed:%s\n", m_pContext->errstr);redisFree(m_pContext);m_pContext = NULL;return -1;}long ret_value = reply->integer;freeReplyObject(reply);return ret_value;
}long CacheConn::decr(string key)
{if (Init()){return -1;}redisReply *reply = (redisReply *)redisCommand(m_pContext, "DECR %s", key.c_str());if (!reply){log_error("redis Command failed:%s\n", m_pContext->errstr);redisFree(m_pContext);m_pContext = NULL;return -1;}long ret_value = reply->integer;freeReplyObject(reply);return ret_value;
}long CacheConn::lpush(string key, string value)
{if (Init()){return -1;}redisReply *reply = (redisReply *)redisCommand(m_pContext, "LPUSH %s %s", key.c_str(), value.c_str());if (!reply){log_error("redisCommand failed:%s\n", m_pContext->errstr);redisFree(m_pContext);m_pContext = NULL;return -1;}long ret_value = reply->integer;freeReplyObject(reply);return ret_value;
}long CacheConn::rpush(string key, string value)
{if (Init()){return -1;}redisReply *reply = (redisReply *)redisCommand(m_pContext, "RPUSH %s %s", key.c_str(), value.c_str());if (!reply){log_error("redisCommand failed:%s\n", m_pContext->errstr);redisFree(m_pContext);m_pContext = NULL;return -1;}long ret_value = reply->integer;freeReplyObject(reply);return ret_value;
}long CacheConn::llen(string key)
{if (Init()){return -1;}redisReply *reply = (redisReply *)redisCommand(m_pContext, "LLEN %s", key.c_str());if (!reply){log_error("redisCommand failed:%s\n", m_pContext->errstr);redisFree(m_pContext);m_pContext = NULL;return -1;}long ret_value = reply->integer;freeReplyObject(reply);return ret_value;
}bool CacheConn::lrange(string key, long start, long end, list<string> &ret_value)
{if (Init()){return false;}redisReply *reply = (redisReply *)redisCommand(m_pContext, "LRANGE %s %d %d", key.c_str(), start, end);if (!reply){log_error("redisCommand failed:%s\n", m_pContext->errstr);redisFree(m_pContext);m_pContext = NULL;return false;}if (reply->type == REDIS_REPLY_ARRAY){for (size_t i = 0; i < reply->elements; i++){redisReply *value_reply = reply->element[i];string value(value_reply->str, value_reply->len);ret_value.push_back(value);}}freeReplyObject(reply);return true;
}bool CacheConn::flushdb()
{bool ret = false;if (Init()){return false;}redisReply *reply = (redisReply *)redisCommand(m_pContext, "FLUSHDB");if (!reply){log_error("redisCommand failed:%s\n", m_pContext->errstr);redisFree(m_pContext);m_pContext = NULL;return false;}if (reply->type == REDIS_REPLY_STRING && strncmp(reply->str, "OK", 2) == 0){ret = true;}freeReplyObject(reply);return ret;
}
///
CachePool::CachePool(const char *pool_name, const char *server_ip, int server_port, int db_index,const char *password, int max_conn_cnt)
{m_pool_name = pool_name;m_server_ip = server_ip;m_server_port = server_port;m_db_index = db_index;m_password = password;m_max_conn_cnt = max_conn_cnt;m_cur_conn_cnt = MIN_CACHE_CONN_CNT;
}CachePool::~CachePool()
{m_free_notify.Lock();for (list<CacheConn *>::iterator it = m_free_list.begin(); it != m_free_list.end(); it++){CacheConn *pConn = *it;delete pConn;}m_free_list.clear();m_cur_conn_cnt = 0;m_free_notify.Unlock();
}int CachePool::Init()
{for (int i = 0; i < m_cur_conn_cnt; i++){CacheConn *pConn = new CacheConn(m_server_ip.c_str(), m_server_port,m_db_index, m_password.c_str(), m_pool_name.c_str());if (pConn->Init()){delete pConn;return 1;}m_free_list.push_back(pConn);}log_info("cache pool: %s, list size: %lu\n", m_pool_name.c_str(), m_free_list.size());return 0;
}CacheConn *CachePool::GetCacheConn()
{m_free_notify.Lock();while (m_free_list.empty()){if (m_cur_conn_cnt >= m_max_conn_cnt){m_free_notify.Wait();}else{CacheConn *p_cache_conn = new CacheConn(m_server_ip.c_str(), m_server_port,m_db_index, m_password.c_str(), m_pool_name.c_str());int ret = p_cache_conn->Init();if (ret){log_error("Init CacheConn failed\n");delete p_cache_conn;m_free_notify.Unlock();return NULL;}else{m_free_list.push_back(p_cache_conn);m_cur_conn_cnt++;log_info("new cache connection: %s, conn_cnt: %d\n", m_pool_name.c_str(), m_cur_conn_cnt);}}}CacheConn *pConn = m_free_list.front();m_free_list.pop_front();m_free_notify.Unlock();return pConn;
}void CachePool::RelCacheConn(CacheConn *p_cache_conn)
{m_free_notify.Lock();list<CacheConn *>::iterator it = m_free_list.begin();for (; it != m_free_list.end(); it++){if (*it == p_cache_conn){break;}}if (it == m_free_list.end()){m_free_list.push_back(p_cache_conn);}m_free_notify.Signal();m_free_notify.Unlock();
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