BOOL exec_pipes(t_pipes *p, t_info *info, FLAG son, FD pi[3])
{
STATUS status_quo;
pid_t pid;
FD w[2];
if (!(pid = -(!((unsigned long)(p->next != NULL)))))
{
if (pipe(w) == -1)
return (FALSE);
if ((pid = xfork()) < 0)
return (FALSE);
}
if (!pid)
{
init_pipe(w, pi, W_IN);
exec_pipes(p->next, info, SON, pi);
return (FALSE);
}
if (p->next)
init_pipe(w, pi, W_OUT);
if (exec_cmd(p->cmd, info, info->son = (son | (2 * (pid > 0))), pi) == FALSE)
return (FALSE);
my_wait(pid, &status_quo);
if (pid < 0)
return (TRUE);
return (get_status(info, status_quo));
}
static void exec_strace(pid_t pid,
int sys,
int was_sys,
long ret)
{
struct user_regs_struct reg;
while (ptrace(PTRACE_SINGLESTEP, pid, NULL, NULL) != -1)
{
my_wait(pid);
if (ptrace(PTRACE_GETREGS, pid, NULL, ((void *)(®))) != -1)
{
if ((ret = ptrace(PTRACE_PEEKTEXT, pid, ((void *)(reg.rip)), NULL))
== -1)
exit(dprintf(2, "ptrace(PREACE_PEEKTEXT Failed\n"));
else
{
if (was_sys == 1 && ((was_sys -= 1) == 0))
print_ret(&g_arg[sys], reg.rax, pid);
else
{
ret &= 0x000000000000ffff;
if ((ret == 0x050FU || ret == 0x80CDU || ret == 0x340FU)
&& ((++was_sys) == 1))
moulitrixdecon(&sys, reg, pid);
}
}
}
}
}
int main(int argc, char * argv[]){
char * line;
pid_t c_pid;
int i;
char * cmd_argv[MAX_ARGS]; //NOTE: use this store your argv array,
// don't go beyond MAX_ARGS
char prompt[1024];
char * tok; //NOTE: This is useful for tokenizatoin
//Need to ignore these signals for terminal control to work
signal(SIGTTIN, SIG_IGN);
signal(SIGTTOU, SIG_IGN);
//for readline setup, don't edit!
rl_bind_key('\t', rl_abort);
while(1){ //fork/exec/wait loop
//setup the prompt
snprintf(prompt, 1024, "fg-shell (%d) #> ",last_pid);
line = readline(prompt); //readline allocates a new line every time, need to free
//read EOF, break
if (line == NULL){
free(line);
printf("\n");
break;
}
//read empty line, continue
if (strcmp(line,"")==0){
free(line);
continue;
}
////////////////////////////////////////////////////////////////
//*DO* EDIT BELOW
//
//FILL IN COMPLETED SOLUTION FROM LAB 5
// - parsing line using strtok into the cmd_argv array
//TODO: See if user entered "fg" command
// If so, try and start the background process and call my_wait()
// If no last background process, report error to STDERR
// Don't forget to give the foreground process control of the terminal
//perform a foreground
if ( strcmp(cmd_argv[0], "fg") == 0){
//TODO: FILL IN HERE
free(line); //free line
continue; //continue the shell after waiting
}
//////////////////////////////////////////////////////////////
//DO NOT EDIT BELOW
//
if ( (c_pid = fork()) == 0 ){
/* CHILD */
//set as it's own process group
setpgrp();
execvp(cmd_argv[0],cmd_argv);
perror("fg-shell"); //error
_exit(2); //hard exit, don't want a fork bomb!
}else if (c_pid > 0){
/* PARENT */
//give child its own process group
if(setpgid(c_pid, c_pid) < 0){
perror("setpgrp");
}
//give child the terminal control
if( tcsetpgrp(0, c_pid) < 0){
perror("tcsetpgrp");
}
//wait for a state change
my_wait();
}else{
/* ERROR */
perror("fork failed");
_exit(2);
}
free(line); //free the current line
}
return 0;
}