//**************************************************************************
// function to parse/manage/execute commands
//**************************************************************************
void manager(command_t* cmd ){
char* temp [MAX_COMMAND_LENGTH];
strcpy(temp, cmd->cmdstr);
char* tokens = strtok(temp, " ");
//cd if the first two chars are cd
if (!strcmp(tokens, "cd")){
run_cd( tokens );
}
//set
else if (!strcmp(tokens, "set")){
run_set( tokens);
}
//echo
else if (!strcmp(tokens, "echo")){
run_echo( tokens );
}
//pwd
else if (!strcmp(tokens, "pwd")){
run_pwd( tokens );
}
//jobs
else if (!strcmp(tokens, "jobs")){
run_jobs( cmd, tokens );
}
//exit command
else if (!strcmp(tokens, "exit") || !strcmp(tokens, "quit") )
terminate(); // Exit Quash
//run an executable
else{
run_exec(cmd, tokens);
}
}
void cmd_handler(int cmd, char *arg)
{
if (cmd < 6) /* handles first lot of commands as they all can be implemented by forking a child process easily */
{
pid_t pid = fork();
if (pid > CHILD_PID) /* parent process wait for child to finish before exiting function and going back to prompt */
{
wait(&pid);
} else if (pid == CHILD_PID) /* forked child process runs entered command */
{
switch (cmd)
{
case 0:
run_clr();
break;
case 1:
run_dir(arg);
break;
case 2:
run_echo(arg);
break;
case 3:
run_environ();
break;
case 4:
run_help();
break;
case 5:
run_pause();
break;
default:
printf("Congratulations! You've broken my code."); /* I really don't think it's possible to get here... */
}
} else
{
fprintf(stderr, "Failed to fork process. Fatal error, exiting program.\n");
exit(1);
}
} else /* handles last commands: because of the way I've implemented the execution of the shell, it would be very inconvenient to handle them in a child process (without using shared memory) */
{
switch (cmd)
{
case 6:
run_quit();
break;
case 7:
run_cd(arg);
break;
default:
printf("Again! You did it again!"); /* again, not really possible */
}
}
}
