有关信号量有关问题

#ifndef __LIBAPS_SEMAPHORE_HPP__

#define __LIBAPS_SEMAPHORE_HPP__


#include <base/platform.hpp>

#include <base/exception.hpp>


namespace aps 

{

    //! 信号量

    class LIBAPS_API Semaphore 

    {

    public:

        Semaphore(unsigned int initial = 0, const char* name = 0) throw(Exception);

        ~Semaphore() throw(Exception);


        void wait() throw(Exception);

        bool tryWait() throw(Exception);

        void post() throw(Exception);


    private:

        struct sem_handle_t;

        sem_handle_t* mHandle;

    };


}


#endif // !__LIBAPS_SEMAPHORE_HPP__


#include <base/semaphore.hpp>

#include <base/platform.hpp>

#include <base/charset.hpp>

#include <base/exception.hpp>

#include <base/toolkit.hpp>

#include <base/logger.hpp>


#ifdef Z_OS_LINUX


#include <fcntl.h>

#include <semaphore.h>

#include <string.h>

#include <cstdlib>

#include <errno.h>


using namespace aps;


struct Semaphore::sem_handle_t 

{

    sem_t* semaphore;

    char* name;

    bool creator;


    sem_handle_t()

    {

        name = NULL;

        semaphore = NULL;

    }

};


Semaphore::Semaphore(unsigned int initial, const char* name) throw(Exception):

mHandle(new sem_handle_t)

{

    if(name)

    {

        sem_t* sem = NULL;

        int flags = O_RDWR | O_CREAT | O_EXCL; //O_CREAT|O_EXCL;

        mHandle->creator = true;


        for (int t = 0; ; t++)

        {

            if (t>0)

                TraceX(eTRACE, _G2U("尝试重新以%d打开信号量%s"), flags, name);

            

            sem = sem_open(name, flags, 0755, initial);

            int r = errno;

            if(sem == SEM_FAILED)

            {

                if(r != EEXIST)

                {

                    logException(Z_SOURCEINFO, r, _G2U("打开信号量%s失败:[%d][%s]"), name, r, Toolkit::formatError(r).c_str());

                }

                else 

                {

                    TraceX(eTRACE, _G2U("信号量%s已存在, 尝试打开"), name);

                    flags = 0;

                    mHandle->creator = false;

                    continue;

                }

            }

            break;

        }

        

        mHandle->semaphore = sem;

        mHandle->name      = strdup(name);

    }

    else

    {

        mHandle->name = 0;

        mHandle->semaphore = new sem_t;