www.pudn.com > CENVID.rar > RESTRICT.CMM

// Restrict.cmm   Allow user to only enter commands from the list provided here. 
 
Count = 0; 
Valid[Count++] = "dir" 
Valid[Count++] = "chkdsk" 
Valid[Count++] = "type" 
Valid[Count++] = "cd" 
Valid[Count++] = "set" 
Valid[Count++] = "IsItFri" 
Valid[Count++] = "DiskFree" 
 
 
main() 
{ 
   while ( True ) {  // True is always true, and so this will loop forever 
      ShowAvailableCommands() 
      Command = GetCommand() 
      // check if this command is in our list 
      for ( i = 0; i < Count; i++ ) { 
         if ( !strcmpi(Command.Root,Valid[i]) ) 
            break 
      } 
      if ( i < Count ) { 
         system(Command.Full) 
      } else { 
         // The command was not found 
         printf("\"%s\" is not an available command!\a\n",Command.Root) 
      } 
   } 
} 
 
ShowAvailableCommands() 
{ 
   printf("\nYour available commands are:\n") 
   for ( i = 0; i < Count; i++ ) 
      printf("%s\t",Valid[i]) 
} 
 
GetCommand()   // Get command from user, return a structure with two elements 
               //  .Root   root name of the command entered 
               //  .Full   complete line of input as entered 
{ 
   printf("\nWhaddya want? ") 
   input.Full = gets() 
   // now figure out what the root was, first copy all of input, then remove space from 
   // beginning, then go to first space character 
   strcpy(input.Root,input.Full) 
   // then remove andy whitespace from beginning of command 
   while( input.Root[0] != 0  &&  isspace(input.Root[0] ) ) 
      input.Root++ 
   // end this string at the first whitespace character 
   for ( c = input.Root; c[0] != 0  &&  !isspace(c[0]); c++ ) ; 
   c[0] = 0 
   return(input) 
}