www.pudn.com > b048008.rar > EventBarrier.cc

#include "EventBarrier.h" 
#include "system.h" 
#include "copyright.h" 
 
extern int threadnum; 
 
EventBarrier::EventBarrier(char *debugname) 
{ 
    name = debugname; 
    state = UNSIGNALED; 
    waitnum = 0; 
    queue_signal = new List(); 
    queue_complete = new List(); 
} 
 
EventBarrier::~EventBarrier() 
{ 
    delete queue_signal; 
    delete queue_complete; 
} 
 
 
//EventBarrier::signal() 
//设置事件栅栏的状态为SIGNALED 
//唤醒所有阻塞于Signal的线程 
//阻塞于Complete 
//恢复事件栅栏的状态为UNSIGNALED 
void EventBarrier::Signal() 
{ 
    Thread *thread; 
    state = SIGNALED; 
    IntStatus oldLevel = interrupt->SetLevel(IntOff); 
    printf("Thread %d唤醒所有阻塞于Signal的线程\n",threadnum); 
    while( (thread = (Thread *)queue_signal->Remove()) != NULL) 
        scheduler->ReadyToRun(thread); 
    printf("Thread %d阻塞于Complete\n",threadnum); 
    queue_complete->Append((void *)currentThread); 
    currentThread->Sleep(); 
    (void) interrupt->SetLevel(oldLevel); 
    state = UNSIGNALED; 
} 
 
 
//EventBarrier::Wait() 
//如果事件栅状态是SIGNALED，则直接返回 
//否则，阻塞于signal 
void EventBarrier::Wait() 
{ 
    waitnum++; 
    if(state == SIGNALED) 
    { 
        printf("事件栅状态是SIGNALED,直接返回\n"); 
        return; 
    } 
    else if(state == UNSIGNALED) 
    { 
        IntStatus oldLevel = interrupt->SetLevel(IntOff); 
        printf("事件栅状态是UNSIGNALED,Thread %d阻塞于signal\n",threadnum); 
        queue_signal->Append((void *)currentThread); 
        currentThread->Sleep(); 
        (void) interrupt->SetLevel(oldLevel); 
    } 
} 
 
//EventBarrier::Complete() 
//如果是最后一个调用Complete者，则唤醒所有阻塞于Complete的线程 
//否则，阻塞于Complete 
void EventBarrier::Complete() 
{ 
    Thread *thread; 
    if(waitnum == 1) 
    { 
        IntStatus oldLevel = interrupt->SetLevel(IntOff); 
        printf("Thread %d 是最后一个调用Complete的线程,唤醒所有阻塞于Complete的线程\n",threadnum); 
        while( (thread = (Thread *)queue_complete->Remove()) != NULL) 
            scheduler->ReadyToRun(thread); 
        (void) interrupt->SetLevel(oldLevel); 
    } 
    else 
    { 
        waitnum--; 
        IntStatus oldLevel = interrupt->SetLevel(IntOff); 
        printf("Thread %d 不是最后一个调用Complete的线程,阻塞于Complete\n",threadnum); 
        queue_complete->Append((void *)currentThread); 
        currentThread->Sleep(); 
        (void) interrupt->SetLevel(oldLevel);  
    } 
} 
 
int EventBarrier::Waiters() 
{ 
    return waitnum; 
}