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[cpp]:  my_systemcall()

 

 

 

 

一、说明

 

  1、  C语言可以用【struct】替代C++的【class】。

 

 

 

二、代码

  1 #include <iostream>
  2 #include <string>
  3 
  4 
  5 // system_calls tables
  6 class c_sys_call_table
  7 {
  8 public:
  9     c_sys_call_table(int no) 
 10     { 
 11         bool j = mf_check(no); 
 12         if ( true == j ) 
 13         { 
 14             mf_run(no);
 15         }
 16         else
 17         {
 18             std::cout <<"[error]#    systemcall(no=" << no << "):    NOT FOUND." << std::endl ;    
 19         }
 20     }
 21     c_sys_call_table(std::string name) 
 22     { 
 23         bool j = mf_check(name); 
 24         if ( true == j ) 
 25         { 
 26             mf_run(name);
 27         }
 28         else
 29         {
 30             std::cout <<"[error]#    systemcall(name=" << name << "):    NOT FOUND." << std::endl ; 
 31         }
 32     }
 33     bool mf_check(int no) 
 34     {
 35         return ( (no >= 0) && (no < 5) ) ;
 36     }
 37     
 38     bool mf_check(std::string name)
 39     {
 40         for(int i=0; i<5; i++)
 41         {
 42             if (name == mv_st[i]) { return true ; } 
 43         }
 44         
 45         return false ;
 46     }
 47     
 48     void mf_run(int no)
 49     {
 50         std::cout <<"[os]#    " << mv_st[no] <<"():    system_call is running !" << std::endl ;
 51     }
 52     void mf_run(std::string name)
 53     {
 54         std::cout <<"[os]#    " << name <<"():    system_call is running !" << std::endl ;
 55     }
 56 private:
 57     std::string  mv_st[5] = { "init", "system", "brk", "exec", "exit" } ;
 58 };
 59 
 60 
 61 // system_call packages
 62 class c_syscalls
 63 {
 64 private:
 65     int mv_sys_no = -1 ;
 66     std::string mv_sys_name = "" ;
 67 public:
 68     c_syscalls(int i):mv_sys_no(i){ c_sys_call_table sci(mv_sys_no) ; }
 69     c_syscalls(std::string s):mv_sys_name(s){ c_sys_call_table sn(mv_sys_name) ; }
 70     void mf_msg()
 71     {
 72         if ( mv_sys_no >= 0 )
 73         {
 74             std::cout << "[os]#    system_call_no := " << mv_sys_no << std::endl ;    
 75         }
 76         else
 77         {
 78             std::cout << "[os]#    system_call_no NOT FOUND := " << mv_sys_no << std::endl ;   
 79         }
 80         
 81         if ( mv_sys_name != "" )
 82         {
 83             std::cout << "[os]#    system_call_name := " << mv_sys_name << std::endl ;   
 84         }
 85         else
 86         {
 87             std::cout << "[os]#    system_call_name NOT FOUND := " << mv_sys_name << std::endl ;       
 88         }
 89     }
 90 };
 91 
 92 
 93 // system call initialization and run
 94 void syscall(int i)
 95 {
 96     c_syscalls si(i) ;
 97 }
 98 void syscall(std::string  n)
 99 {
100     c_syscalls sn(n) ;
101 }
102 
103 
104 // entry port
105 int main()
106 {
107     syscall(1) ;
108     syscall("exit") ;
109     
110     syscall(5) ;
111     syscall("big") ;
112     
113     return 0 ;
114 }

 

 

三、运行

g++ -std=c++20 -O2 -Wall -pedantic -pthread main.cpp && ./a.out


[os]#    system():    system_call is running !
[os]#    exit():    system_call is running !
[error]#    systemcall(no=5):    NOT FOUND.
[error]#    systemcall(name=big):    NOT FOUND.

 

 

四、参考文档

 

  1、无

 

posted on 2024-02-01 23:57  lnlidawei  阅读(6)  评论(0编辑  收藏  举报