c++实现的一个邮箱，用于线程间通信

我想知道是否有人以前使用POSIX库实现了用于线程间通信的邮箱类。作为参考，我看起来类似于SystemVerilog中使用的邮箱:http://www.asic-world.com/systemverilog/sema_mail_events2.html

编辑:

我尝试使用STL队列、pthread条件和互斥锁访问邮箱。它尝试复制链接中描述的SystemVerilog邮箱的行为:

#include <cerrno>
#include <climits>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <queue>
#include <fcntl.h>
#include <pthread.h>
#include <sys/select.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
using namespace std;
class Mailbox{
    private:
        pthread_cond_t  msg_available;  // Message in the mailbox?
        pthread_mutex_t queue_mutex;    // Mutex for queue control
        queue<messageT> messages;       // Messages
    public:
        // Constructor
        Mailbox(void){
            msg_available = PTHREAD_COND_INITIALIZER;
            queue_mutex = PTHREAD_MUTEX_INITIALIZER;
        }
        // Destructor
        ~Mailbox(void){
            // Nothing to do here
        }
        // Put a single message into the mailbox
        void put(messageT msg){
            // Lock down queue
            if(pthread_mutex_lock(queue_mutex)){
                fprintf(stderr, "Queue Mutex Lock Errorn");
                exit(EXIT_FAILURE);
            }
            // Push message into mailbox
            messages.push(msg);
            // Signal there is a message in the mailbox
            if(pthread_cond_signal(&msg_available)){                    
                fprintf(stderr, "cond error");
                exit(EXIT_FAILURE);
            }
            // Unlock queue
            if(pthread_mutex_unlock(queue_mutex)){
                fprintf(stderr, "Queue Mutex Unlock Errorn");
                exit(EXIT_FAILURE);
            }
        }
        // Try to put a single message into the mailbox
        int try_put(messageT msg){
            // Try to lock down queue
            if(pthread_mutex_trylock(queue_mutex) == 0){
                // Push message into mailbox
                messages.push(msg);
                // Signal there is a message in the mailbox
                if(pthread_cond_signal(&msg_available)){                    
                    fprintf(stderr, "cond error");
                    exit(EXIT_FAILURE);
                }
                // Unlock queue
                if(pthread_mutex_unlock(queue_mutex)){
                    fprintf(stderr, "Queue Mutex Unlock Errorn");
                    exit(EXIT_FAILURE);
                }
                return 1;
            }
            // Otherwise, say mailbox is unavailable
            else
                return 0;
        }
        //  Get single message from a mailbox
        void get(mesageT *msg){
            // Lock down queue
            if(pthread_mutex_lock(queue_mutex)){
                fprintf(stderr, "Queue Mutex Lock Errorn");
                exit(EXIT_FAILURE);
            }
            // Wait for a message to come in
            while(messages.empty()){
                // Release hold of the lock until another thread
                // signals that a message has been placed
                if(pthread_cond_wait(&msg_available,&queue_mutex)){                 
                    fprintf(stderr, "cond_wait error");
                    exit(EXIT_FAILURE);
                }
            }
            // Pop of least recent message
            *msg = messages.front();
            messages.pop();
            // Unlock queue
            if(pthread_mutex_unlock(queue_mutex)){
                fprintf(stderr, "Queue Mutex Unlock Errorn");
                exit(EXIT_FAILURE);
            }
        }
        //  Try to get single message from a mailbox
        int try_get(mesageT *msg){
            int mailbox_ready = 1;  // Mailbox ready
            // Lock down queue
            if(pthread_mutex_lock(queue_mutex)){
                fprintf(stderr, "Queue Mutex Lock Errorn");
                exit(EXIT_FAILURE);
            }
            // Indicate if mailbox is empty
            if(messages.empty())
                mailbox_ready = 0
            // Otherwise, grab the message
            else {
                // Pop of least recent message
                *msg = messages.front();
                messages.pop();
            }
            // Unlock queue
            if(pthread_mutex_unlock(queue_mutex)){
                fprintf(stderr, "Queue Mutex Unlock Errorn");
                exit(EXIT_FAILURE);
            }
            return mailbox_ready;
        }
        //  Peek at single message from a mailbox
        void peek(mesageT *msg){
            // Lock down queue
            if(pthread_mutex_lock(queue_mutex)){
                fprintf(stderr, "Queue Mutex Lock Errorn");
                exit(EXIT_FAILURE);
            }
            // Wait for a message to come in
            while(messages.empty()){
                // Release hold of the lock until another thread
                // signals that a message has been placed
                if(pthread_cond_wait(&msg_available,&queue_mutex)){                 
                    fprintf(stderr, "cond_wait error");
                    exit(EXIT_FAILURE);
                }
            }
            // Peek at most recent message
            *msg = messages.front();
            // Unlock queue
            if(pthread_mutex_unlock(queue_mutex)){
                fprintf(stderr, "Queue Mutex Unlock Errorn");
                exit(EXIT_FAILURE);
            }
        }
        //  Try to peek at single message from a mailbox
        int try_peek(mesageT *msg){
            int mailbox_ready = 1;  // Mailbox ready
            // Lock down queue
            if(pthread_mutex_lock(queue_mutex)){
                fprintf(stderr, "Queue Mutex Lock Errorn");
                exit(EXIT_FAILURE);
            }
            if(messages.empty())    // Indicate if mailbox is empty
                mailbox_ready = 0
            else                    // Otherwise, grab the message
                *msg = messages.front();
            // Unlock queue
            if(pthread_mutex_unlock(queue_mutex)){
                fprintf(stderr, "Queue Mutex Unlock Errorn");
                exit(EXIT_FAILURE);
            }
            return mailbox_ready;
        }
}