I created a parent Server, there is a way to server_poll, within the Server constructor calls,

Then I inherit Server, and created a subclass process_sub_1, then rewrite the method server_poll, expect process_sub_1 when creating objects, the constructor will call me new rewritten process_sub_1: : server_poll,

But in the actual debugging, calls the constructor to create process_sub_1 object, will not use process_sub_1: : server_poll, but still USES the Server: : server_poll

Everybody to help, please look at my code, how to improve




Specific engineering stored in the cloud, using cmake compiled under ubuntu, specific see code readme

A network backup link: https://pan.baidu.com/s/1UhyfD7ORK-4FeOvYHL-AZA
The extracted code: d63q



The definition of the Server class

 
The class Server {

Public: 
Pid_t pid; 

EServer service_id; 
Char name [MY_PID_NAME_LEN]; 

//subclass inherits rewrite 
Void server_init (void * par, uint32_t len) {} 
Void server_poll (void) {} 

Uint32_t Server (eServer id, void * par, len); 
To the Server (); 

The static Server * install (eServer id, void * par, uint32_t len); 
The static Server * self; 

}; 

The following is a Server class constructor

 Server: Server (eServer id, void * par, uint32_t len) {

Uint8_t I=0; 
Pid_t pid=fork (); 

This - & gt; Service_id=id; 
Bzero (this - & gt; The name, MY_PID_NAME_LEN); 
Len=strlen (mServiceName [this - & gt; service_id]); 
If (len & gt; MY_PID_NAME_LEN) {
Len=MY_PID_NAME_LEN; 
} 

Memcpy (name, mServiceName [this - & gt; service_id], MY_PID_NAME_LEN); 

If (pid & gt; 0) {//the parent process, the return value is the child of pid 
This - & gt; Pid=pid; 
return ; 
} 

Else if (pid==0) {//the child process, the return value of 0 

int ret=0; 

//the name of the new process of modified 
PRCTL (PR_SET_NAME, this - & gt; The name, NULL, NULL, NULL); 

//to get his own PID 
This - & gt; Pid=getpid (); 

//application initialization, here by subclasses override 
This - & gt; Server_init (par, len); 

//application business cycle, by subclasses override here, should be written in infinite loop 
This - & gt; Server_poll (); 

Printf (" Warning!!!!!! \n"); 
The exit (EXIT_FAILURE); 

} 
The else {
Printf (" Warning!!!!!! \n"); 
return ; 
} 


} 

The definition of the following for process_sub_1 class

 class process_sub_1: public Server {
Private: 
Uint32_t void server_init (void * par, len); 
Void server_poll (void); 

Public: 
Uint32_t process_sub_1 (eServer id, void * par, len) : Server (id, par, len) {

} 

}; 

The realization of the process_sub_1 class

 # include "process_sub_1. H" 

Void process_sub_1: : server_init (void * par, uint32_t len) {

} 

Void process_sub_1: : server_poll (void) {

While (1) {
Printf (" process_sub_1 \ n "); 
Usleep (1000 * 2000); 
} 

} 

The main main function:

 

Int main (void) {
Process_sub_1: : install (eSubService1, NULL, 0); 
While (1) {
Sleep (1); 
} 
} 

The final test results:

Ubuntu#./bin/my_test
Server
Server

CodePudding user response:

Don't inside the constructor call virtual functions,

CodePudding user response:

Please see the explanations in the Efficient c + +

CodePudding user response:

Code can't see a virtual keyword, but also rewritten?
Even override the virtual function, in the constructor call didn't also effect of polymorphism,

To improve is to use a function independent of the constructor to handle,