Linux下编写一个程序库，实现定时器的功能,它能为用户提供在同一进程中多次使用的定时器。
二、实现
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <sys/queue.h>
#include <sys/time.h>
#include <pthread.h>
#include <errno.h>
#define DEFAULT_INTERVAL 1
int TIMER_CNT = 0;
class Timer; //定时器
class TimerManager; //定时器管理器
class TimerManager {
friend class Timer; //友元类,Timer类可分享此类的方法
public:
typedef enum {
TIMER_MANAGER_STOP=0,
TIMER_MANAGER_START
}TimerManagerState;
static TimerManager *instance(); //当前实例
void start(); //启动当前线程，运行process函数
void stop(); //终止当前线程
void dump(); //清理当前剩下的无用定时器
void add_timer(Timer *vtimer); //线程安全的增加定时器
void remove_timer(Timer *vtimer); //线程安全的移除定时器
protected:
static void *process(void *);
private:
TimerManager();
void add_timer_unsafe(Timer *vtimer); //线程非安全的增加定时器，本类使用
void remove_timer_unsafe(Timer *vtimer);//线程非安全的移除定时器，本类使用
static TimerManager *m_instance;
static pthread_mutex_t workmutex;
TimerManagerState m_state;
LIST_HEAD(,Timer) list_; //链表头
static int mark;
};
class Timer {
friend class TimerManager;
public:
typedef enum {
TIMER_IDLE = 0,
TIMER_ALIVE,
TIMER_TIMEOUT
}TimerState;
Timer(int vinterval,void (*vfunc)(void *),void *vdata);
void start(); //把自己添加进定时器管理器的链表里
void stop(); //把自己从定时器管理器的链表里移除
void reset(int vinterval); //重置
~Timer();
private:
int id; //当前定时器的ID
int m_interval; //定时器的定时时间，单位为秒
int m_counter; //还剩下多少时间，单位为微秒
TimerState m_state; //当前定时器的状态
void (*m_func)(void *);
void *m_data;
LIST_ENTRY(Timer) entry_; //当前定时器在链表中的地址
};
TimerManager *TimerManager::m_instance;
pthread_mutex_t TimerManager::workmutex;
TimerManager::TimerManager() {
pthread_mutex_init(&workmutex,NULL);
}
TimerManager *TimerManager::instance() {
if (m_instance == NULL) {
pthread_mutex_lock(&workmutex);
if (m_instance == NULL)
m_instance = new TimerManager();
pthread_mutex_unlock(&workmutex);
}
return m_instance;
}
void TimerManager::start() {
if (m_state == TIMER_MANAGER_STOP) {
m_state = TIMER_MANAGER_START;
pthread_t pid;
int res = pthread_create(&pid,NULL,process,this);
if (res != 0) {
printf("pthread_create is failed\n");
exit(EXIT_FAILURE);
}
}
}
void TimerManager::stop() {
this->m_state = TIMER_MANAGER_STOP;
}
void TimerManager::dump() {
Timer *item;
pthread_mutex_lock(&workmutex);
LIST_FOREACH(item,&(this->list_),entry_) {
if (item->m_counter == 0) {