Net2/usr/src/usr.bin/gdb/inflow.c
/*-
* This code is derived from software copyrighted by the Free Software
* Foundation.
*
* Modified 1991 by Donn Seeley at UUNET Technologies, Inc.
* Modified 1990 by Van Jacobson at Lawrence Berkeley Laboratory.
*/
#ifndef lint
static char sccsid[] = "@(#)inflow.c 6.5 (Berkeley) 5/8/91";
#endif /* not lint */
/* Low level interface to ptrace, for GDB when running under Unix.
Copyright (C) 1986, 1987, 1989 Free Software Foundation, Inc.
This file is part of GDB.
GDB is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 1, or (at your option)
any later version.
GDB is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with GDB; see the file COPYING. If not, write to
the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
#include <stdio.h>
#include "defs.h"
#include "param.h"
#include "frame.h"
#include "inferior.h"
#ifdef USG
#include <sys/types.h>
#endif
/* Some USG-esque systems (some of which are BSD-esque enough so that USG
is not defined) want this header, and it won't do any harm. */
#include <fcntl.h>
#include <sys/param.h>
#include <sys/dir.h>
#include <signal.h>
#ifdef HAVE_TERMIO
#include <termio.h>
#undef TIOCGETP
#define TIOCGETP TCGETA
#undef TIOCSETN
#define TIOCSETN TCSETA
#undef TIOCSETP
#define TIOCSETP TCSETAF
#define TERMINAL struct termio
#else
#include <sys/ioctl.h>
#include <fcntl.h>
#include <sgtty.h>
#define TERMINAL struct sgttyb
#endif
#ifdef SET_STACK_LIMIT_HUGE
#include <sys/time.h>
#include <sys/resource.h>
extern int original_stack_limit;
#endif /* SET_STACK_LIMIT_HUGE */
extern int errno;
/* Nonzero if we are debugging an attached outside process
rather than an inferior. */
int attach_flag;
/* Record terminal status separately for debugger and inferior. */
static TERMINAL sg_inferior;
static TERMINAL sg_ours;
static int tflags_inferior;
static int tflags_ours;
#if defined(TIOCGETC) && !defined(TIOCGETC_BROKEN)
static struct tchars tc_inferior;
static struct tchars tc_ours;
#endif
#ifdef TIOCGLTC
static struct ltchars ltc_inferior;
static struct ltchars ltc_ours;
#endif
#ifdef TIOCLGET
static int lmode_inferior;
static int lmode_ours;
#endif
#ifdef TIOCGPGRP
static int pgrp_inferior;
static int pgrp_ours;
#else
static int (*sigint_ours) ();
static int (*sigquit_ours) ();
#endif /* TIOCGPGRP */
/* Copy of inferior_io_terminal when inferior was last started. */
static char *inferior_thisrun_terminal;
static void terminal_ours_1 ();
/* Nonzero if our terminal settings are in effect.
Zero if the inferior's settings are in effect. */
static int terminal_is_ours;
/* Initialize the terminal settings we record for the inferior,
before we actually run the inferior. */
void
terminal_init_inferior ()
{
if (remote_debugging)
return;
sg_inferior = sg_ours;
tflags_inferior = tflags_ours;
#if defined(TIOCGETC) && !defined(TIOCGETC_BROKEN)
tc_inferior = tc_ours;
#endif
#ifdef TIOCGLTC
ltc_inferior = ltc_ours;
#endif
#ifdef TIOCLGET
lmode_inferior = lmode_ours;
#endif
#ifdef TIOCGPGRP
pgrp_inferior = inferior_pid;
#endif /* TIOCGPGRP */
terminal_is_ours = 1;
}
/* Put the inferior's terminal settings into effect.
This is preparation for starting or resuming the inferior. */
void
terminal_inferior ()
{
if (remote_debugging)
return;
if (terminal_is_ours) /* && inferior_thisrun_terminal == 0) */
{
fcntl (0, F_SETFL, tflags_inferior);
fcntl (0, F_SETFL, tflags_inferior);
ioctl (0, TIOCSETN, &sg_inferior);
#if defined(TIOCGETC) && !defined(TIOCGETC_BROKEN)
ioctl (0, TIOCSETC, &tc_inferior);
#endif
#ifdef TIOCGLTC
ioctl (0, TIOCSLTC, <c_inferior);
#endif
#ifdef TIOCLGET
ioctl (0, TIOCLSET, &lmode_inferior);
#endif
#ifdef TIOCGPGRP
ioctl (0, TIOCSPGRP, &pgrp_inferior);
#else
sigint_ours = (int (*) ()) signal (SIGINT, SIG_IGN);
sigquit_ours = (int (*) ()) signal (SIGQUIT, SIG_IGN);
#endif /* TIOCGPGRP */
}
terminal_is_ours = 0;
}
/* Put some of our terminal settings into effect,
enough to get proper results from our output,
but do not change into or out of RAW mode
so that no input is discarded.
After doing this, either terminal_ours or terminal_inferior
should be called to get back to a normal state of affairs. */
void
terminal_ours_for_output ()
{
if (remote_debugging)
return;
terminal_ours_1 (1);
}
/* Put our terminal settings into effect.
First record the inferior's terminal settings
so they can be restored properly later. */
void
terminal_ours ()
{
if (remote_debugging)
return;
terminal_ours_1 (0);
}
static void
terminal_ours_1 (output_only)
int output_only;
{
#ifdef TIOCGPGRP
/* Ignore this signal since it will happen when we try to set the pgrp. */
void (*osigttou) ();
#endif /* TIOCGPGRP */
if (!terminal_is_ours) /* && inferior_thisrun_terminal == 0) */
{
terminal_is_ours = 1;
#ifdef TIOCGPGRP
osigttou = signal (SIGTTOU, SIG_IGN);
ioctl (0, TIOCGPGRP, &pgrp_inferior);
ioctl (0, TIOCSPGRP, &pgrp_ours);
signal (SIGTTOU, osigttou);
#else
signal (SIGINT, sigint_ours);
signal (SIGQUIT, sigquit_ours);
#endif /* TIOCGPGRP */
tflags_inferior = fcntl (0, F_GETFL, 0);
ioctl (0, TIOCGETP, &sg_inferior);
#if defined(TIOCGETC) && !defined(TIOCGETC_BROKEN)
ioctl (0, TIOCGETC, &tc_inferior);
#endif
#ifdef TIOCGLTC
ioctl (0, TIOCGLTC, <c_inferior);
#endif
#ifdef TIOCLGET
ioctl (0, TIOCLGET, &lmode_inferior);
#endif
}
#ifdef HAVE_TERMIO
sg_ours.c_lflag |= ICANON;
if (output_only && !(sg_inferior.c_lflag & ICANON))
sg_ours.c_lflag &= ~ICANON;
#else /* not HAVE_TERMIO */
sg_ours.sg_flags &= ~RAW & ~CBREAK;
if (output_only)
sg_ours.sg_flags |= (RAW | CBREAK) & sg_inferior.sg_flags;
#endif /* not HAVE_TERMIO */
fcntl (0, F_SETFL, tflags_ours);
fcntl (0, F_SETFL, tflags_ours);
ioctl (0, TIOCSETN, &sg_ours);
#if defined(TIOCGETC) && !defined(TIOCGETC_BROKEN)
ioctl (0, TIOCSETC, &tc_ours);
#endif
#ifdef TIOCGLTC
ioctl (0, TIOCSLTC, <c_ours);
#endif
#ifdef TIOCLGET
ioctl (0, TIOCLSET, &lmode_ours);
#endif
#ifdef HAVE_TERMIO
sg_ours.c_lflag |= ICANON;
#else /* not HAVE_TERMIO */
sg_ours.sg_flags &= ~RAW & ~CBREAK;
#endif /* not HAVE_TERMIO */
}
static void
term_status_command ()
{
register int i;
if (remote_debugging)
{
printf_filtered ("No terminal status when remote debugging.\n");
return;
}
printf_filtered ("Inferior's terminal status (currently saved by GDB):\n");
#ifdef HAVE_TERMIO
printf_filtered ("fcntl flags = 0x%x, c_iflag = 0x%x, c_oflag = 0x%x,\n",
tflags_inferior, sg_inferior.c_iflag, sg_inferior.c_oflag);
printf_filtered ("c_cflag = 0x%x, c_lflag = 0x%x, c_line = 0x%x.\n",
sg_inferior.c_cflag, sg_inferior.c_lflag, sg_inferior.c_line);
printf_filtered ("c_cc: ");
for (i = 0; (i < NCC); i += 1)
printf_filtered ("0x%x ", sg_inferior.c_cc[i]);
printf_filtered ("\n");
#else /* not HAVE_TERMIO */
printf_filtered ("fcntl flags = 0x%x, sgttyb.sg_flags = 0x%x, owner pid = %d.\n",
tflags_inferior, sg_inferior.sg_flags, pgrp_inferior);
#endif /* not HAVE_TERMIO */
#if defined(TIOCGETC) && !defined(TIOCGETC_BROKEN)
printf_filtered ("tchars: ");
for (i = 0; i < sizeof (struct tchars); i++)
printf_filtered ("0x%x ", ((char *)&tc_inferior)[i]);
printf_filtered ("\n");
#endif
#ifdef TIOCGLTC
printf_filtered ("ltchars: ");
for (i = 0; i < sizeof (struct ltchars); i++)
printf_filtered ("0x%x ", ((char *)<c_inferior)[i]);
printf_filtered ("\n");
ioctl (0, TIOCSLTC, <c_ours);
#endif
#ifdef TIOCLGET
printf_filtered ("lmode: %x\n", lmode_inferior);
#endif
}
static void
new_tty (ttyname)
char *ttyname;
{
register int tty;
register int fd;
#ifdef TIOCNOTTY
/* Disconnect the child process from our controlling terminal. */
tty = open("/dev/tty", O_RDWR);
if (tty > 0)
{
ioctl(tty, TIOCNOTTY, 0);
close(tty);
}
#endif
/* Now open the specified new terminal. */
tty = open(ttyname, O_RDWR);
if (tty == -1)
_exit(1);
/* Avoid use of dup2; doesn't exist on all systems. */
if (tty != 0)
{ close (0); dup (tty); }
if (tty != 1)
{ close (1); dup (tty); }
if (tty != 2)
{ close (2); dup (tty); }
if (tty > 2)
close(tty);
}
/* Start an inferior process and returns its pid.
ALLARGS is a string containing shell command to run the program.
ENV is the environment vector to pass. */
#ifndef SHELL_FILE
#define SHELL_FILE "/bin/sh"
#endif
int
create_inferior (allargs, env)
char *allargs;
char **env;
{
int pid;
char *shell_command;
extern int sys_nerr;
extern char *sys_errlist[];
extern int errno;
/* If desired, concat something onto the front of ALLARGS.
SHELL_COMMAND is the result. */
#ifdef SHELL_COMMAND_CONCAT
shell_command = (char *) alloca (strlen (SHELL_COMMAND_CONCAT) + strlen (allargs) + 1);
strcpy (shell_command, SHELL_COMMAND_CONCAT);
strcat (shell_command, allargs);
#else
shell_command = allargs;
#endif
/* exec is said to fail if the executable is open. */
close_exec_file ();
#if defined(USG) && !defined(HAVE_VFORK)
pid = fork ();
#else
pid = vfork ();
#endif
if (pid < 0)
perror_with_name ("vfork");
if (pid == 0)
{
#ifdef TIOCGPGRP
/* Run inferior in a separate process group. */
setpgrp (getpid (), getpid ());
#endif /* TIOCGPGRP */
#ifdef SET_STACK_LIMIT_HUGE
/* Reset the stack limit back to what it was. */
{
struct rlimit rlim;
getrlimit (RLIMIT_STACK, &rlim);
rlim.rlim_cur = original_stack_limit;
setrlimit (RLIMIT_STACK, &rlim);
}
#endif /* SET_STACK_LIMIT_HUGE */
inferior_thisrun_terminal = inferior_io_terminal;
if (inferior_io_terminal != 0)
new_tty (inferior_io_terminal);
/* It seems that changing the signal handlers for the inferior after
a vfork also changes them for the superior. See comments in
initialize_signals for how we get the right signal handlers
for the inferior. */
/* Not needed on Sun, at least, and loses there
because it clobbers the superior. */
/*??? signal (SIGQUIT, SIG_DFL);
signal (SIGINT, SIG_DFL); */
call_ptrace (0);
execle (SHELL_FILE, "sh", "-c", shell_command, 0, env);
fprintf (stderr, "Cannot exec %s: %s.\n", SHELL_FILE,
errno < sys_nerr ? sys_errlist[errno] : "unknown error");
fflush (stderr);
_exit (0177);
}
#ifdef TIOCGPGRP
/* Avoid race with TIOCSPGRP: guarantee that inferior's pgrp exists. */
setpgrp (pid, pid);
#endif /* TIOCGPGRP */
#ifdef CREATE_INFERIOR_HOOK
CREATE_INFERIOR_HOOK (pid);
#endif
return pid;
}
/* Kill the inferior process. Make us have no inferior. */
static void
kill_command ()
{
if (remote_debugging)
{
inferior_pid = 0;
return;
}
if (inferior_pid == 0)
error ("The program is not being run.");
if (!query ("Kill the inferior process? "))
error ("Not confirmed.");
kill_inferior ();
}
void
inferior_died ()
{
inferior_pid = 0;
attach_flag = 0;
mark_breakpoints_out ();
select_frame ((FRAME) 0, -1);
reopen_exec_file ();
if (have_core_file_p ())
set_current_frame ( create_new_frame (read_register (FP_REGNUM),
read_pc ()));
else
set_current_frame (0);
}
#if 0
/* This function is just for testing, and on some systems (Sony NewsOS
3.2) <sys/user.h> also includes <sys/time.h> which leads to errors
(since on this system at least sys/time.h is not protected against
multiple inclusion). */
static void
try_writing_regs_command ()
{
register int i;
register int value;
extern int errno;
if (inferior_pid == 0)
error ("There is no inferior process now.");
/* A Sun 3/50 or 3/60 (at least) running SunOS 4.0.3 will have a
kernel panic if we try to write past the end of the user area.
Presumably Sun will fix this bug (it has been reported), but it
is tacky to crash the system, so at least on SunOS4 we need to
stop writing when we hit the end of the user area. */
for (i = 0; i < sizeof (struct user); i += 2)
{
QUIT;
errno = 0;
value = call_ptrace (3, inferior_pid, i, 0);
call_ptrace (6, inferior_pid, i, value);
if (errno == 0)
{
printf (" Succeeded with address 0x%x; value 0x%x (%d).\n",
i, value, value);
}
else if ((i & 0377) == 0)
printf (" Failed at 0x%x.\n", i);
}
}
#endif
void
_initialize_inflow ()
{
add_com ("term-status", class_obscure, term_status_command,
"Print info on inferior's saved terminal status.");
#if 0
add_com ("try-writing-regs", class_obscure, try_writing_regs_command,
"Try writing all locations in inferior's system block.\n\
Report which ones can be written.");
#endif
add_com ("kill", class_run, kill_command,
"Kill execution of program being debugged.");
inferior_pid = 0;
ioctl (0, TIOCGETP, &sg_ours);
tflags_ours = fcntl (0, F_GETFL, 0);
#if defined(TIOCGETC) && !defined(TIOCGETC_BROKEN)
ioctl (0, TIOCGETC, &tc_ours);
#endif
#ifdef TIOCGLTC
ioctl (0, TIOCGLTC, <c_ours);
#endif
#ifdef TIOCLGET
ioctl (0, TIOCLGET, &lmode_ours);
#endif
#ifdef TIOCGPGRP
ioctl (0, TIOCGPGRP, &pgrp_ours);
#endif /* TIOCGPGRP */
terminal_is_ours = 1;
}