rlfe.c

gdb-6.8 Linux下的调试程序 最新版本

    {
      if (argv[arg_base][0] != '-')
	break;
      if (arg_base+1 >= argc )
	usage_exit();
      switch(argv[arg_base][1])
	{
	case 'h':
	  arg_base++;
	  hist_file = argv[arg_base];
	  break;
	case 's':
	  arg_base++;
	  hist_size = atoi(argv[arg_base]);
	  if (hist_size<0)
	    usage_exit();
	  break;
	default:
	  usage_exit();
	}
      arg_base++;
    }
  if (hist_file)
    read_history (hist_file);

  set_edit_mode ();

  rl_readline_name = APPLICATION_NAME;
  
  if ((master = OpenPTY (&name)) < 0)
    {
      perror("ptypair: could not open master pty");
      exit(1);
    }

  DPRINT1("pty name: '%s'\n", name);

  /* set up SIGWINCH handler */
  act.sa_handler = sigwinch_handler;
  sigemptyset(&(act.sa_mask));
  act.sa_flags = 0;
  if (sigaction(SIGWINCH, &act, NULL) < 0)
    {
      perror("ptypair: could not handle SIGWINCH ");
      exit(1);
    }

  if (ioctl(STDIN_FILENO, TIOCGWINSZ, &ws) < 0)
    {
      perror("ptypair: could not get window size");
      exit(1);
    }

  if ((child = fork()) < 0)
    {
      perror("cannot fork");
      exit(1);
    }

  if (child == 0)
    { 
      int slave;  /* file descriptor for slave pty */

      /* We are in the child process */
      close(master);

#ifdef TIOCSCTTY
      if ((slave = get_slave_pty(name)) < 0)
	{
	  perror("ptypair: could not open slave pty");
	  exit(1);
	}
#endif

      /* We need to make this process a session group leader, because
       * it is on a new PTY, and things like job control simply will
       * not work correctly unless there is a session group leader
       * and process group leader (which a session group leader
       * automatically is). This also disassociates us from our old
       * controlling tty. 
       */
      if (setsid() < 0)
	{
	  perror("could not set session leader");
	}

      /* Tie us to our new controlling tty. */
#ifdef TIOCSCTTY
      if (ioctl(slave, TIOCSCTTY, NULL))
	{
	  perror("could not set new controlling tty");
	}
#else
      if ((slave = get_slave_pty(name)) < 0)
	{
	  perror("ptypair: could not open slave pty");
	  exit(1);
	}
#endif

      /* make slave pty be standard in, out, and error */
      dup2(slave, STDIN_FILENO);
      dup2(slave, STDOUT_FILENO);
      dup2(slave, STDERR_FILENO);

      /* at this point the slave pty should be standard input */
      if (slave > 2)
	{
	  close(slave);
	}

      /* Try to restore window size; failure isn't critical */
      if (ioctl(STDOUT_FILENO, TIOCSWINSZ, &ws) < 0)
	{
	  perror("could not restore window size");
	}

      /* now start the shell */
      {
	static char* command_args[] = { COMMAND_ARGS, NULL };
	static char* alt_command_args[] = { ALT_COMMAND_ARGS, NULL };
	if (argc <= 1)
	  {
	    execvp (COMMAND, command_args);
	    execvp (ALT_COMMAND, alt_command_args);
	  }
	else
	  execvp (argv[arg_base], &argv[arg_base]);
      }

      /* should never be reached */
      exit(1);
    }

  /* parent */
  signal (SIGCHLD, sig_child);

  /* Note that we only set termios settings for standard input;
   * the master side of a pty is NOT a tty.
   */
  tcgetattr(STDIN_FILENO, &orig_term);

  t = orig_term;
  eof_char = t.c_cc[VEOF];
  /*  add_special_char(t.c_cc[VEOF]);*/
  add_special_char(t.c_cc[VINTR]);
  add_special_char(t.c_cc[VQUIT]);
  add_special_char(t.c_cc[VSUSP]);
#if defined (VDISCARD)
  add_special_char(t.c_cc[VDISCARD]);
#endif

  t.c_lflag &= ~(ICANON | ISIG | ECHO | ECHOCTL | ECHOE | \
		 ECHOK | ECHOKE | ECHONL | ECHOPRT );
  t.c_iflag &= ~ICRNL;
  t.c_iflag |= IGNBRK;
  t.c_cc[VMIN] = 1;
  t.c_cc[VTIME] = 0;
  tcsetattr(STDIN_FILENO, TCSANOW, &t);
  in_from_inferior_fd = master;
  out_to_inferior_fd = master;
  rl_instream = fdopen (master, "r");
  rl_getc_function = my_rl_getc;

  rl_prep_term_function = null_prep_terminal; 
  rl_deprep_term_function = null_deprep_terminal;
  rl_pre_input_hook = pre_input_change_mode;
  rl_callback_handler_install (prompt, line_handler);

  in_from_tty_fd = STDIN_FILENO;
  FD_ZERO (&in_set);
  maxfd = in_from_inferior_fd > in_from_tty_fd ? in_from_inferior_fd
    : in_from_tty_fd;
  for (;;)
    {
      int num;
      FD_SET (in_from_inferior_fd, &in_set);
      FD_SET (in_from_tty_fd, &in_set);

      num = select(maxfd+1, &in_set, NULL, NULL, NULL);

      if (propagate_sigwinch)
	{
	  struct winsize ws;
	  if (ioctl (STDIN_FILENO, TIOCGWINSZ, &ws) >= 0)
	    {
	      ioctl (master, TIOCSWINSZ, &ws);
	    }
	  propagate_sigwinch = 0;
	  continue;
	}

      if (num <= 0)
	{
	  perror ("select");
	  exit (-1);
	}
      if (FD_ISSET (in_from_tty_fd, &in_set))
	{
	  extern int readline_echoing_p;
	  struct termios term_master;
	  int do_canon = 1;
	  int do_icrnl = 1;
	  int ioctl_ret;

	  DPRINT1("[tty avail num_keys:%d]\n", num_keys);

	  /* If we can't get tty modes for the master side of the pty, we
	     can't handle non-canonical-mode programs.  Always assume the
	     master is in canonical echo mode if we can't tell. */
	  ioctl_ret = tcgetattr(master, &term_master);

	  if (ioctl_ret >= 0)
	    {
	      do_canon = (term_master.c_lflag & ICANON) != 0;
	      do_icrnl = (term_master.c_lflag & ICRNL) != 0;
	      readline_echoing_p = (term_master.c_lflag & ECHO) != 0;
	      DPRINT1 ("echo,canon,crnl:%03d\n",
		       100 * readline_echoing_p
		       + 10 * do_canon
		       + 1 * do_icrnl);
	    }
	  else
	    {
	      if (ioctl_err == 0)
		DPRINT1("tcgetattr on master fd failed: errno = %d\n", errno);
	      ioctl_err = 1;
	    }

	  if (do_canon == 0 && num_keys == 0)
	    {
	      char ch[10];
	      int count = read (STDIN_FILENO, ch, sizeof(ch));
	      DPRINT1("[read %d chars from stdin: ", count);
	      DPRINT2(" \"%.*s\"]\n", count, ch);
	      if (do_icrnl)
		{
		  int i = count;
		  while (--i >= 0)
		    {
		      if (ch[i] == '\r')
			ch[i] = '\n';
		    }
		}
	      maybe_emphasize_input (1);
	      write (out_to_inferior_fd, ch, count);
	    }
	  else
	    {
	      if (num_keys == 0)
		{
		  int i;
		  /* Re-install callback handler for new prompt. */
		  if (prompt != empty_string)
		    free (prompt);
		  if (prompt == NULL)
		    {
		      DPRINT0("New empty prompt\n");
		      prompt = empty_string;
		    }
		  else
		    {
		      if (do_emphasize_input && buf_count > 0)
			{
			  prompt = malloc (buf_count + strlen (end_input_mode)
					   + strlen (start_input_mode) + 5);
			  sprintf (prompt, "\001%s\002%.*s\001%s\002",
				   end_input_mode,
				   buf_count, buf,
				   start_input_mode);
			}
		      else
			{
			  prompt = malloc (buf_count + 1);
			  memcpy (prompt, buf, buf_count);
			  prompt[buf_count] = '\0';
			}
		      DPRINT1("New prompt '%s'\n", prompt);
#if 0 /* ifdef HAVE_RL_ALREADY_PROMPTED */
		      /* Doesn't quite work when do_emphasize_input is 1. */
		      rl_already_prompted = buf_count > 0;
#else
		      if (buf_count > 0)
			write (1, "\r", 1);
#endif
		    }

		  rl_callback_handler_install (prompt, line_handler);
		}
	      num_keys++;
	      maybe_emphasize_input (1);
	      rl_callback_read_char ();
	    }
	}
      else /* output from inferior. */
	{
	  int i;
	  int count;
	  int old_count;
	  if (buf_count > (sizeof(buf) >> 2))
	    buf_count = 0;
	  count = read (in_from_inferior_fd, buf+buf_count,
			sizeof(buf) - buf_count);
          DPRINT2("read %d from inferior, buf_count=%d", count, buf_count);
	  DPRINT2(": \"%.*s\"", count, buf+buf_count);
	  maybe_emphasize_input (0);
	  if (count <= 0)
	    {
	      DPRINT0 ("(Connection closed by foreign host.)\n");
	      tcsetattr(STDIN_FILENO, TCSANOW, &orig_term);
	      exit (0);
	    }
	  old_count = buf_count;

          /* Look for any pending echo that we need to suppress. */
	  while (echo_suppress_start < echo_suppress_limit
		 && count > 0
		 && buf[buf_count] == echo_suppress_buffer[echo_suppress_start])
	    {
	      count--;
	      buf_count++;
	      echo_suppress_start++;
	    }
	  DPRINT1("suppressed %d characters of echo.\n", buf_count-old_count);

          /* Write to the terminal anything that was not suppressed. */
          if (count > 0)
            write (1, buf + buf_count, count);

          /* Finally, look for a prompt candidate.
           * When we get around to going input (from the keyboard),
           * we will consider the prompt to be anything since the last
           * line terminator.  So we need to save that text in the
           * initial part of buf.  However, anything before the
           * most recent end-of-line is not interesting. */
	  buf_count += count;
#if 1
	  for (i = buf_count;  --i >= old_count; )
#else
	  for (i = buf_count - 1;  i-- >= buf_count - count; )
#endif
	    {
	      if (buf[i] == '\n' || buf[i] == '\r')
		{
		  i++;
		  memmove (buf, buf+i, buf_count - i);
		  buf_count -= i;
		  break;
		}
	    }
	  DPRINT2("-> i: %d, buf_count: %d\n", i, buf_count);
	}
    }
}

static void set_edit_mode ()
{
  int vi = 0;
  char *shellopts;

  shellopts = getenv ("SHELLOPTS");
  while (shellopts != 0)
    {
      if (strncmp ("vi", shellopts, 2) == 0)
	{
	  vi = 1;
	  break;
	}
      shellopts = index (shellopts + 1, ':');
    }

  if (!vi)
    {
      if (getenv ("EDITOR") != 0)
	vi |= strcmp (getenv ("EDITOR"), "vi") == 0;
    }

  if (vi)
    rl_variable_bind ("editing-mode", "vi");
  else
    rl_variable_bind ("editing-mode", "emacs");
}


static void usage_exit ()
{
  fprintf (stderr, "Usage: rlfe [-h histfile] [-s size] cmd [arg1] [arg2] ...\n\n");
  exit (1);
}