死锁

#include 
     
      #include 
      
       #include 
       
        #include 
        
         class LofFile{public:    void shared_print(std::string name , int num)    {        std::lock_guard
         
           locker(m_mutex) ;        std::lock_guard
          
            locker2(m_mutex2) ; std::cout<
           
            <<": "<
            
             <
             
               locker2(m_mutex2) ; std::lock_guard
              
                locker(m_mutex) ; std::cout<
               
                <<": "<
                
                 <
                 
                  -100 ;i--) { log.shared_print("子线程",i); }}int main(){ LofFile log ; std::thread t(thread_fun,std::ref(log)); for(int i=0 ;i<100;i++) { log.shared_print2("主线程",i); } t.join(); return 0;}
                 
                
               
              
             
            
           
          
         
        
       
      
     

 

解决死锁方法1：使mutex顺序相同

#include 
     
      #include 
      
       #include 
       
        #include 
        
         class LofFile{public:    void shared_print(std::string name , int num)    {        std::lock_guard
         
           locker(m_mutex) ;        std::lock_guard
          
            locker2(m_mutex2) ; std::cout<
           
            <<": "<
            
             <
             
               locker(m_mutex) ; std::lock_guard
              
                locker2(m_mutex2) ; std::cout<
               
                <<": "<
                
                 <
                 
                  -100 ;i--) { log.shared_print("子线程",i); }}int main(){ LofFile log ; std::thread t(thread_fun,std::ref(log)); for(int i=0 ;i<100;i++) { log.shared_print2("主线程",i); } t.join(); return 0;}
                 
                
               
              
             
            
           
          
         
        
       
      
     

解决死锁方法2：使用std::lock

#include 
     
      #include 
      
       #include 
       
        #include 
        
         class LofFile{public:    void shared_print(std::string name , int num)    {        std::lock(m_mutex,m_mutex2);        std::lock_guard
         
           locker(m_mutex,std::adopt_lock) ;        std::lock_guard
          
            locker2(m_mutex2,std::adopt_lock) ; std::cout<
           
            <<": "<
            
             <
             
               locker2(m_mutex2,std::adopt_lock) ; std::lock_guard
              
                locker(m_mutex,std::adopt_lock) ; std::cout<
               
                <<": "<
                
                 <
                 
                  -100 ;i--) { log.shared_print("子线程",i); }}int main(){ LofFile log ; std::thread t(thread_fun,std::ref(log)); for(int i=0 ;i<100;i++) { log.shared_print2("主线程",i); } t.join(); return 0;}