重庆分公司,新征程启航
为企业提供网站建设、域名注册、服务器等服务
#includewindows.h
成都创新互联公司凭借专业的设计团队扎实的技术支持、优质高效的服务意识和丰厚的资源优势,提供专业的网站策划、网站建设、网站设计、网站优化、软件开发、网站改版等服务,在成都10余年的网站建设设计经验,为成都数千家中小型企业策划设计了网站。
#includefstream.h
#includestdio.h
#includestring
#includeconio.h
//定义一些常量;
//本程序允许的最大临界区数;
#define MAX_BUFFER_NUM 10
//秒到微秒的乘法因子;
#define INTE_PER_SEC 1000
//本程序允许的生产和消费线程的总数;
#define MAX_THREAD_NUM 64
//定义一个结构,记录在测试文件中指定的每一个线程的参数
struct ThreadInfo
{
int serial; //线程序列号
char entity; //是P还是C
double delay; //线程延迟
int thread_request[MAX_THREAD_NUM]; //线程请求队列
int n_request; //请求个数
};
//全局变量的定义
//临界区对象的声明,用于管理缓冲区的互斥访问;
CRITICAL_SECTION PC_Critical[MAX_BUFFER_NUM];
int Buffer_Critical[MAX_BUFFER_NUM]; //缓冲区声明,用于存放产品;
HANDLE h_Thread[MAX_THREAD_NUM]; //用于存储每个线程句柄的数组;
ThreadInfo Thread_Info[MAX_THREAD_NUM]; //线程信息数组;
HANDLE empty_semaphore; //一个信号量;
HANDLE h_mutex; //一个互斥量;
DWORD n_Thread = 0; //实际的线程的数目;
DWORD n_Buffer_or_Critical; //实际的缓冲区或者临界区的数目;
HANDLE h_Semaphore[MAX_THREAD_NUM]; //生产者允许消费者开始消费的信号量;
//生产消费及辅助函数的声明
void Produce(void *p);
void Consume(void *p);
bool IfInOtherRequest(int);
int FindProducePositon();
int FindBufferPosition(int);
int main(void)
{
//声明所需变量;
DWORD wait_for_all;
ifstream inFile;
//初始化缓冲区;
for(int i=0;i MAX_BUFFER_NUM;i++)
Buffer_Critical[i] = -1;
//初始化每个线程的请求队列;
for(int j=0;jMAX_THREAD_NUM;j++){
for(int k=0;kMAX_THREAD_NUM;k++)
Thread_Info[j].thread_request[k] = -1;
Thread_Info[j].n_request = 0;
}
//初始化临界区;
for(i =0;i MAX_BUFFER_NUM;i++)
InitializeCriticalSection(PC_Critical[i]);
//打开输入文件,按照规定的格式提取线程等信息;
inFile.open("test.txt");
//从文件中获得实际的缓冲区的数目;
inFile n_Buffer_or_Critical;
inFile.get();
printf("输入文件是:\n");
//回显获得的缓冲区的数目信息;
printf("%d \n",(int) n_Buffer_or_Critical);
//提取每个线程的信息到相应数据结构中;
while(inFile){
inFile Thread_Info[n_Thread].serial;
inFile Thread_Info[n_Thread].entity;
inFile Thread_Info[n_Thread].delay;
char c;
inFile.get(c);
while(c!='\n' !inFile.eof()){
inFile Thread_Info[n_Thread].thread_request[Thread_Info[n_Thread].n_request++];
inFile.get(c);
}
n_Thread++;
}
//回显获得的线程信息,便于确认正确性;
for(j=0;j(int) n_Thread;j++){
int Temp_serial = Thread_Info[j].serial;
char Temp_entity = Thread_Info[j].entity;
double Temp_delay = Thread_Info[j].delay;
printf(" \n thread%2d %c %f ",Temp_serial,Temp_entity,Temp_delay);
int Temp_request = Thread_Info[j].n_request;
for(int k=0;kTemp_request;k++)
printf(" %d ", Thread_Info[j].thread_request[k]);
coutendl;
}
printf("\n\n");
//创建在模拟过程中几个必要的信号量
empty_semaphore=CreateSemaphore(NULL,n_Buffer_or_Critical,n_Buffer_or_Critical,
"semaphore_for_empty");
h_mutex = CreateMutex(NULL,FALSE,"mutex_for_update");
//下面这个循环用线程的ID号来为相应生产线程的产品读写时所
//使用的同步信号量命名;
for(j=0;j(int)n_Thread;j++){
std::string lp ="semaphore_for_produce_";
int temp =j;
while(temp){
char c = (char)(temp%10);
lp+=c;
temp/=10;
}
h_Semaphore[j+1]=CreateSemaphore(NULL,0,n_Thread,lp.c_str());
}
//创建生产者和消费者线程;
for(i =0;i (int) n_Thread;i++){
if(Thread_Info[i].entity =='P')
h_Thread[i]= CreateThread(NULL,0,(LPTHREAD_START_ROUTINE)(Produce),
(Thread_Info[i]),0,NULL);
else
h_Thread[i]=CreateThread(NULL,0,(LPTHREAD_START_ROUTINE)(Consume),
(Thread_Info[i]),0,NULL);
}
//主程序等待各个线程的动作结束;
wait_for_all = WaitForMultipleObjects(n_Thread,h_Thread,TRUE,-1);
printf(" \n \nALL Producer and consumer have finished their work. \n");
printf("Press any key to quit!\n");
_getch();
return 0;
}
//确认是否还有对同一产品的消费请求未执行;
bool IfInOtherRequest(int req)
{
for(int i=0;in_Thread;i++)
for(int j=0;jThread_Info[i].n_request;j++)
if(Thread_Info[i].thread_request[j] == req)
return TRUE;
return FALSE;
}
//找出当前可以进行产品生产的空缓冲区位置;
int FindProducePosition()
{
int EmptyPosition;
for (int i =0;in_Buffer_or_Critical;i++)
if(Buffer_Critical[i] == -1){
EmptyPosition = i;
//用下面这个特殊值表示本缓冲区正处于被写状态;
Buffer_Critical[i] = -2;
break;
}
return EmptyPosition;
}
//找出当前所需生产者生产的产品的位置;
int FindBufferPosition(int ProPos)
{
int TempPos;
for (int i =0 ;in_Buffer_or_Critical;i++)
if(Buffer_Critical[i]==ProPos){
TempPos = i;
break;
}
return TempPos;
}
//生产者进程
void Produce(void *p)
{
//局部变量声明;
DWORD wait_for_semaphore,wait_for_mutex,m_delay;
int m_serial;
//获得本线程的信息;
m_serial = ((ThreadInfo*)(p))-serial;
m_delay = (DWORD)(((ThreadInfo*)(p))-delay *INTE_PER_SEC);
Sleep(m_delay);
//开始请求生产
printf("Producer %2d sends the produce require.\n",m_serial);
//确认有空缓冲区可供生产,同时将空位置数empty减1;用于生产者和消费者的同步;
wait_for_semaphore = WaitForSingleObject(empty_semaphore,-1);
//互斥访问下一个可用于生产的空临界区,实现写写互斥;
wait_for_mutex = WaitForSingleObject(h_mutex,-1);
int ProducePos = FindProducePosition();
ReleaseMutex(h_mutex);
//生产者在获得自己的空位置并做上标记后,以下的写操作在生产者之间可以并发;
//核心生产步骤中,程序将生产者的ID作为产品编号放入,方便消费者识别;
printf("Producer %2d begin to produce at position %2d.\n",m_serial,ProducePos);
Buffer_Critical[ProducePos] = m_serial;
printf("Producer %2d finish producing :\n ",m_serial);
printf(" position[ %2d ]:%3d \n" ,ProducePos,Buffer_Critical[ProducePos]);
//使生产者写的缓冲区可以被多个消费者使用,实现读写同步;
ReleaseSemaphore(h_Semaphore[m_serial],n_Thread,NULL);
}
//消费者进程
void Consume(void * p)
{
//局部变量声明;
DWORD wait_for_semaphore,m_delay;
int m_serial,m_requestNum; //消费者的序列号和请求的数目;
int m_thread_request[MAX_THREAD_NUM];//本消费线程的请求队列;
//提取本线程的信息到本地;
m_serial = ((ThreadInfo*)(p))-serial;
m_delay = (DWORD)(((ThreadInfo*)(p))-delay *INTE_PER_SEC);
m_requestNum = ((ThreadInfo *)(p))-n_request;
for (int i = 0;im_requestNum;i++)
m_thread_request[i] = ((ThreadInfo*)(p))-thread_request[i];
Sleep(m_delay);
//循环进行所需产品的消费
for(i =0;im_requestNum;i++){
//请求消费下一个产品
printf("Consumer %2d request to consume %2d product\n",m_serial,m_thread_request[i]);
//如果对应生产者没有生产,则等待;如果生产了,允许的消费者数目-1;实现了读写同步;
wait_for_semaphore=WaitForSingleObject(h_Semaphore[m_thread_request[i]],-1);
//查询所需产品放到缓冲区的号
int BufferPos=FindBufferPosition(m_thread_request[i]);
//开始进行具体缓冲区的消费处理,读和读在该缓冲区上仍然是互斥的;
//进入临界区后执行消费动作;并在完成此次请求后,通知另外的消费者本处请求已
//经满足;同时如果对应的产品使用完毕,就做相应处理;并给出相应动作的界面提
//示;该相应处理指将相应缓冲区清空,并增加代表空缓冲区的信号量;
EnterCriticalSection(PC_Critical[BufferPos]);
printf("Consumer%2d begin to consume %2d product \n",m_serial,m_thread_request[i]);
((ThreadInfo*)(p))-thread_request[i] =-1;
if(!IfInOtherRequest(m_thread_request[i])){
Buffer_Critical[BufferPos] = -1;//标记缓冲区为空;
printf("Consumer%2d finish consuming %2d:\n ",m_serial,m_thread_request[i]);
printf(" position[ %2d ]:%3d \n" ,BufferPos,Buffer_Critical[BufferPos]);
ReleaseSemaphore(empty_semaphore,1,NULL);
}
else{
printf("Consumer %2d finish consuming product %2d\n ",m_serial,m_thread_request[i]);
}
//离开临界区
LeaveCriticalSection(PC_Critical[BufferPos]);
}
}
看函数就行
用 pthread_t创建线程名字。然后pthread_create开辟线程。
具体使用。
比如有一个函数
void *hello()
{
printf("create pthread!\n");
}
,然后在main函数里面调用,
int main()
{
pthread_t a_thread;
pthread_create(a_thread, NULL, (void *)hello, NULL);
}
这样就完成了hello()函数的创建和使用,接下来hello函数就会在一个线程中运行
线程跟makefile没有关系
用fork或者pthread_* api来使用进程和线程
·线程创建
函数原型:int pthread_create(pthread_t *restrict tidp,const pthread_attr_t *restrict attr,void *(*start_rtn)(void),void *restrict arg);
返回值:若是成功建立线程返回0,否则返回错误的编号。
形式参数:pthread_t *restrict tidp要创建的线程的线程id指针;
const pthread_attr_t *restrict attr创建线程时的线程属性;
void* (start_rtn)(void)返回值是void类型的指针函数;
void *restrict arg start_rtn的形参。 =====这个地方就可以传参数,
注意,这个地方是个指针,要想传多个参数,可以定义一个结构体,把要传的参数包起来,传结构体的地址就ok
int pthread_create(pthread_t *tidp,const pthread_attr_t *attr,
(void*)(*start_rtn)(void*),void *arg);