一个线程池的例子（三）

来源：互联网发布：java do while循环语句编辑：程序博客网时间：2024/05/18 05:37
在Linux下，我们使用pthread线程库来进行线程编程，下面是一个线程池的简单例子，还望各位多多指教。
main.cpp
/* * main.cpp * *  Created on: 2014年12月14日 *      Author: Richard */#include <pthread.h>#include <stdio.h>#include <vector>#include <iostream>#include <math.h>using namespace std;struct Task{    long m_StartValue;    long m_EndValue;    long m_MinResultValue;    long m_MaxResultValue;    long long m_SumResultValue;    Task()    {        m_StartValue = 0;        m_EndValue = 0;        m_MinResultValue = 0;        m_MaxResultValue = 0;        m_SumResultValue = 0;    }    Task &operator=(const Task &T)    {        if (this != &T)        {            m_StartValue = T.m_StartValue;            m_EndValue = T.m_EndValue;            m_MinResultValue = T.m_MinResultValue;            m_MaxResultValue = T.m_MaxResultValue;            m_SumResultValue = T.m_SumResultValue;        }        return *this;    }};vector<Task> g_TaskList;pthread_cond_t g_CondFinished;pthread_mutex_t g_TaskMutex;pthread_cond_t g_CondStart;int g_TaskCount = 0;bool IsPrime(unsigned long n){    if (n == 2)    {        return true;    }    if (n % 2 == 0 || n < 2)    {        return false;    }    long tmp = (int)sqrt((double)n);    for (long i = 3; i <= tmp; i += 2)    {        if (n % i == 0)        {            return false;        }    }    return true;}void CalCulatePrime(Task &T){    long PrimesCount = 0;    for (long i = T.m_StartValue; i < T.m_EndValue; i++)    {        if (IsPrime(i))        {            PrimesCount++;            if (PrimesCount == 1)            {                T.m_MinResultValue = i;            }            T.m_SumResultValue = T.m_SumResultValue + (long long)i;        }    }    PrimesCount = 0;    for (long i = T.m_EndValue - 1; i >= T.m_StartValue; i--)    {        if (IsPrime(i))        {            PrimesCount++;            if (PrimesCount == 1)            {                T.m_MaxResultValue = i;                break;            }        }    }}void *ThreadFunc(void *){    pthread_mutex_lock(&g_TaskMutex);    while (g_TaskCount == 0)    {        pthread_cond_wait(&g_CondStart, &g_TaskMutex);    }    pthread_mutex_unlock(&g_TaskMutex);    while(1)    {        if (g_TaskList.size() == 0) {            break;        }        pthread_mutex_lock(&g_TaskMutex);        Task T = g_TaskList.at(0);        g_TaskList.erase(g_TaskList.begin());        pthread_mutex_unlock(&g_TaskMutex);        CalCulatePrime(T);        printf("ThreadID: %lu, Start: %ld, End: %ld, MinResult: %ld, MaxResult: %ld, SumResult: %lld\n",            pthread_self(), T.m_StartValue, T.m_EndValue, T.m_MinResultValue, T.m_MaxResultValue,            T.m_SumResultValue);        pthread_mutex_lock(&g_TaskMutex);        g_TaskCount--;        if (g_TaskCount == 0)        {            pthread_cond_signal(&g_CondFinished);            pthread_mutex_unlock(&g_TaskMutex);            break;        }        pthread_mutex_unlock(&g_TaskMutex);    }    return NULL;}int main(int argc, char **argv) {    pthread_mutex_init(&g_TaskMutex, NULL);    pthread_cond_init(&g_CondStart, NULL);    pthread_cond_init(&g_CondFinished, NULL);    pthread_t ThreadID[8];    for (int i = 0; i < 8; i++)    {        pthread_create(&ThreadID[i], NULL, ThreadFunc, NULL);    }    for (int i = 0; i < 50; i++)    {        Task T;        T.m_StartValue = i * 1000;        T.m_EndValue = (i + 1) * 1000 * 100;        g_TaskList.push_back(T);        g_TaskCount++;    }    pthread_mutex_lock(&g_TaskMutex);    pthread_cond_broadcast(&g_CondStart);    pthread_mutex_unlock(&g_TaskMutex);    pthread_mutex_lock(&g_TaskMutex);    while(g_TaskCount > 0)    {        pthread_cond_wait(&g_CondFinished, &g_TaskMutex);    }    pthread_mutex_unlock(&g_TaskMutex);    for(int i = 0; i < 8; i++)    {        pthread_join(ThreadID[i], NULL);    }    pthread_mutex_destroy(&g_TaskMutex);    pthread_cond_destroy(&g_CondFinished);    pthread_cond_destroy(&g_CondStart);    return 0;}
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