src/ipc.h

   1 #ifndef IPC_H
   2 #define IPC_H
   3
   4 #define _POSIX_C_SOURCE 200809L
   5 #include <signal.h>
   6 #include <stdbool.h>
   7 #include <sys/wait.h>
   8 #include <unistd.h>
   9 #include "try.h"
  10
  11 typedef struct {
  12         int read;
  13         int write;
  14 } Pipe;
  15
  16 static void accept_signal(int const signum, bool const accept) {
  17         if (signal(signum, accept ? SIG_DFL : SIG_IGN) == SIG_ERR) {
  18                 pexit("signal()");
  19         }
  20 }
  21
  22 static void accept_interactive_signals(bool const accept) {
  23         accept_signal(SIGINT, accept);
  24         accept_signal(SIGQUIT, accept);
  25         accept_signal(SIGTSTP, accept);
  26 }
  27
  28 static Pipe make_pipe() {
  29         Pipe p;
  30         int fds[2];
  31         if (pipe(fds) == -1) {
  32                 pexit("pipe()");
  33         }
  34         p.read = fds[0];
  35         p.write = fds[1];
  36         return p;
  37 }
  38
  39 static void move_fd(int const old, int const new) {
  40         if (dup2(old, new) == -1) {
  41                 pexit("dup2()");
  42         }
  43         close(old);
  44 }
  45
  46 static int wait_script(pid_t const pid) {
  47         int status = try_waitpid(pid, WUNTRACED);
  48         while (WIFSTOPPED(status)) {
  49                 if (WSTOPSIG(status) == SIGTSTP) {
  50                         accept_signal(SIGTSTP, true);
  51                         raise(SIGTSTP);
  52                         accept_signal(SIGTSTP, false);
  53                 }
  54                 status = try_waitpid(pid, WUNTRACED);
  55         }
  56         if (WIFSIGNALED(status)) {
  57                 switch (WTERMSIG(status)) {
  58                 case SIGINT:
  59                         accept_signal(SIGINT, true);
  60                         raise(SIGINT);
  61                 case SIGQUIT: exit(EXIT_FAILURE);
  62                 }
  63         }
  64         return status;
  65 }
  66
  67 #endif