1999-04-16 01:35:26 +00:00
|
|
|
/* Fork a Unix child process, and set up to debug it, for GDB.
|
2001-03-06 08:22:02 +00:00
|
|
|
Copyright 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1998, 1999, 2000,
|
|
|
|
2001 Free Software Foundation, Inc.
|
1999-04-16 01:35:26 +00:00
|
|
|
Contributed by Cygnus Support.
|
|
|
|
|
1999-07-07 20:19:36 +00:00
|
|
|
This file is part of GDB.
|
1999-04-16 01:35:26 +00:00
|
|
|
|
1999-07-07 20:19:36 +00:00
|
|
|
This program 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 2 of the License, or
|
|
|
|
(at your option) any later version.
|
1999-04-16 01:35:26 +00:00
|
|
|
|
1999-07-07 20:19:36 +00:00
|
|
|
This program 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.
|
1999-04-16 01:35:26 +00:00
|
|
|
|
1999-07-07 20:19:36 +00:00
|
|
|
You should have received a copy of the GNU General Public License
|
|
|
|
along with this program; if not, write to the Free Software
|
|
|
|
Foundation, Inc., 59 Temple Place - Suite 330,
|
|
|
|
Boston, MA 02111-1307, USA. */
|
1999-04-16 01:35:26 +00:00
|
|
|
|
|
|
|
#include "defs.h"
|
|
|
|
#include "gdb_string.h"
|
|
|
|
#include "frame.h" /* required by inferior.h */
|
|
|
|
#include "inferior.h"
|
|
|
|
#include "target.h"
|
2000-02-09 08:52:47 +00:00
|
|
|
#include "gdb_wait.h"
|
2001-01-31 02:08:23 +00:00
|
|
|
#include "gdb_vfork.h"
|
1999-04-16 01:35:26 +00:00
|
|
|
#include "gdbcore.h"
|
|
|
|
#include "terminal.h"
|
|
|
|
#include "gdbthread.h"
|
1999-12-07 03:56:43 +00:00
|
|
|
#include "command.h" /* for dont_repeat () */
|
1999-04-16 01:35:26 +00:00
|
|
|
|
|
|
|
#include <signal.h>
|
|
|
|
|
|
|
|
/* This just gets used as a default if we can't find SHELL */
|
|
|
|
#ifndef SHELL_FILE
|
|
|
|
#define SHELL_FILE "/bin/sh"
|
|
|
|
#endif
|
|
|
|
|
|
|
|
extern char **environ;
|
|
|
|
|
|
|
|
/* This function breaks up an argument string into an argument
|
|
|
|
* vector suitable for passing to execvp().
|
|
|
|
* E.g., on "run a b c d" this routine would get as input
|
|
|
|
* the string "a b c d", and as output it would fill in argv with
|
|
|
|
* the four arguments "a", "b", "c", "d".
|
|
|
|
*/
|
|
|
|
static void
|
2000-07-30 01:48:28 +00:00
|
|
|
breakup_args (char *scratch, char **argv)
|
1999-04-16 01:35:26 +00:00
|
|
|
{
|
|
|
|
char *cp = scratch;
|
|
|
|
|
|
|
|
for (;;)
|
|
|
|
{
|
|
|
|
|
|
|
|
/* Scan past leading separators */
|
|
|
|
while (*cp == ' ' || *cp == '\t' || *cp == '\n')
|
|
|
|
{
|
|
|
|
cp++;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Break if at end of string */
|
|
|
|
if (*cp == '\0')
|
|
|
|
break;
|
|
|
|
|
|
|
|
/* Take an arg */
|
|
|
|
*argv++ = cp;
|
|
|
|
|
|
|
|
/* Scan for next arg separator */
|
|
|
|
cp = strchr (cp, ' ');
|
|
|
|
if (cp == NULL)
|
|
|
|
cp = strchr (cp, '\t');
|
|
|
|
if (cp == NULL)
|
|
|
|
cp = strchr (cp, '\n');
|
|
|
|
|
|
|
|
/* No separators => end of string => break */
|
|
|
|
if (cp == NULL)
|
|
|
|
break;
|
|
|
|
|
|
|
|
/* Replace the separator with a terminator */
|
|
|
|
*cp++ = '\0';
|
|
|
|
}
|
|
|
|
|
|
|
|
/* execv requires a null-terminated arg vector */
|
|
|
|
*argv = NULL;
|
|
|
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
2001-05-04 04:15:33 +00:00
|
|
|
/* Start an inferior Unix child process and sets inferior_ptid to its pid.
|
1999-04-16 01:35:26 +00:00
|
|
|
EXEC_FILE is the file to run.
|
|
|
|
ALLARGS is a string containing the arguments to the program.
|
|
|
|
ENV is the environment vector to pass. SHELL_FILE is the shell file,
|
|
|
|
or NULL if we should pick one. Errors reported with error(). */
|
|
|
|
|
2001-03-23 22:48:44 +00:00
|
|
|
/* This function is NOT-REENTRANT. Some of the variables have been
|
|
|
|
made static to ensure that they survive the vfork() call. */
|
|
|
|
|
1999-04-16 01:35:26 +00:00
|
|
|
void
|
2001-03-23 22:48:44 +00:00
|
|
|
fork_inferior (char *exec_file_arg, char *allargs, char **env,
|
2000-08-23 16:37:23 +00:00
|
|
|
void (*traceme_fun) (void), void (*init_trace_fun) (int),
|
2001-03-23 22:48:44 +00:00
|
|
|
void (*pre_trace_fun) (void), char *shell_file_arg)
|
1999-04-16 01:35:26 +00:00
|
|
|
{
|
|
|
|
int pid;
|
|
|
|
char *shell_command;
|
|
|
|
static char default_shell_file[] = SHELL_FILE;
|
|
|
|
int len;
|
|
|
|
/* Set debug_fork then attach to the child while it sleeps, to debug. */
|
|
|
|
static int debug_fork = 0;
|
|
|
|
/* This is set to the result of setpgrp, which if vforked, will be visible
|
|
|
|
to you in the parent process. It's only used by humans for debugging. */
|
|
|
|
static int debug_setpgrp = 657473;
|
2001-03-23 22:48:44 +00:00
|
|
|
static char *shell_file;
|
|
|
|
static char *exec_file;
|
1999-04-16 01:35:26 +00:00
|
|
|
char **save_our_env;
|
|
|
|
int shell = 0;
|
2001-03-23 22:48:44 +00:00
|
|
|
static char **argv;
|
1999-04-16 01:35:26 +00:00
|
|
|
|
|
|
|
/* If no exec file handed to us, get it from the exec-file command -- with
|
|
|
|
a good, common error message if none is specified. */
|
2001-03-23 22:48:44 +00:00
|
|
|
exec_file = exec_file_arg;
|
1999-04-16 01:35:26 +00:00
|
|
|
if (exec_file == 0)
|
|
|
|
exec_file = get_exec_file (1);
|
|
|
|
|
|
|
|
/* STARTUP_WITH_SHELL is defined in inferior.h.
|
|
|
|
* If 0, we'll just do a fork/exec, no shell, so don't
|
|
|
|
* bother figuring out what shell.
|
|
|
|
*/
|
2001-03-23 22:48:44 +00:00
|
|
|
shell_file = shell_file_arg;
|
1999-04-16 01:35:26 +00:00
|
|
|
if (STARTUP_WITH_SHELL)
|
|
|
|
{
|
|
|
|
/* Figure out what shell to start up the user program under. */
|
|
|
|
if (shell_file == NULL)
|
|
|
|
shell_file = getenv ("SHELL");
|
|
|
|
if (shell_file == NULL)
|
|
|
|
shell_file = default_shell_file;
|
|
|
|
shell = 1;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Multiplying the length of exec_file by 4 is to account for the fact
|
|
|
|
that it may expand when quoted; it is a worst-case number based on
|
|
|
|
every character being '. */
|
1999-07-07 20:19:36 +00:00
|
|
|
len = 5 + 4 * strlen (exec_file) + 1 + strlen (allargs) + 1 + /*slop */ 12;
|
1999-04-16 01:35:26 +00:00
|
|
|
/* 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) + len);
|
|
|
|
strcpy (shell_command, SHELL_COMMAND_CONCAT);
|
|
|
|
#else
|
|
|
|
shell_command = (char *) alloca (len);
|
|
|
|
shell_command[0] = '\0';
|
|
|
|
#endif
|
|
|
|
|
|
|
|
if (!shell)
|
|
|
|
{
|
|
|
|
/* We're going to call execvp. Create argv */
|
|
|
|
/* Largest case: every other character is a separate arg */
|
|
|
|
argv = (char **) xmalloc (((strlen (allargs) + 1) / (unsigned) 2 + 2) * sizeof (*argv));
|
|
|
|
argv[0] = exec_file;
|
|
|
|
breakup_args (allargs, &argv[1]);
|
|
|
|
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
|
|
|
|
/* We're going to call a shell */
|
|
|
|
|
|
|
|
/* Now add exec_file, quoting as necessary. */
|
|
|
|
|
|
|
|
char *p;
|
|
|
|
int need_to_quote;
|
|
|
|
|
|
|
|
strcat (shell_command, "exec ");
|
|
|
|
|
|
|
|
/* Quoting in this style is said to work with all shells. But csh
|
1999-07-07 20:19:36 +00:00
|
|
|
on IRIX 4.0.1 can't deal with it. So we only quote it if we need
|
|
|
|
to. */
|
1999-04-16 01:35:26 +00:00
|
|
|
p = exec_file;
|
|
|
|
while (1)
|
|
|
|
{
|
|
|
|
switch (*p)
|
|
|
|
{
|
|
|
|
case '\'':
|
2002-02-07 06:11:55 +00:00
|
|
|
case '!':
|
1999-04-16 01:35:26 +00:00
|
|
|
case '"':
|
|
|
|
case '(':
|
|
|
|
case ')':
|
|
|
|
case '$':
|
|
|
|
case '&':
|
|
|
|
case ';':
|
|
|
|
case '<':
|
|
|
|
case '>':
|
|
|
|
case ' ':
|
|
|
|
case '\n':
|
|
|
|
case '\t':
|
|
|
|
need_to_quote = 1;
|
|
|
|
goto end_scan;
|
|
|
|
|
|
|
|
case '\0':
|
|
|
|
need_to_quote = 0;
|
|
|
|
goto end_scan;
|
|
|
|
|
|
|
|
default:
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
++p;
|
|
|
|
}
|
|
|
|
end_scan:
|
|
|
|
if (need_to_quote)
|
|
|
|
{
|
|
|
|
strcat (shell_command, "'");
|
|
|
|
for (p = exec_file; *p != '\0'; ++p)
|
|
|
|
{
|
|
|
|
if (*p == '\'')
|
|
|
|
strcat (shell_command, "'\\''");
|
2002-02-07 06:11:55 +00:00
|
|
|
else if (*p == '!')
|
|
|
|
strcat (shell_command, "\\!");
|
1999-04-16 01:35:26 +00:00
|
|
|
else
|
|
|
|
strncat (shell_command, p, 1);
|
|
|
|
}
|
|
|
|
strcat (shell_command, "'");
|
|
|
|
}
|
|
|
|
else
|
|
|
|
strcat (shell_command, exec_file);
|
|
|
|
|
|
|
|
strcat (shell_command, " ");
|
|
|
|
strcat (shell_command, allargs);
|
|
|
|
|
|
|
|
}
|
|
|
|
|
|
|
|
/* exec is said to fail if the executable is open. */
|
|
|
|
close_exec_file ();
|
|
|
|
|
|
|
|
/* Retain a copy of our environment variables, since the child will
|
|
|
|
replace the value of environ and if we're vforked, we have to
|
|
|
|
restore it. */
|
|
|
|
save_our_env = environ;
|
|
|
|
|
|
|
|
/* Tell the terminal handling subsystem what tty we plan to run on;
|
|
|
|
it will just record the information for later. */
|
|
|
|
|
|
|
|
new_tty_prefork (inferior_io_terminal);
|
|
|
|
|
|
|
|
/* It is generally good practice to flush any possible pending stdio
|
|
|
|
output prior to doing a fork, to avoid the possibility of both the
|
|
|
|
parent and child flushing the same data after the fork. */
|
|
|
|
|
|
|
|
gdb_flush (gdb_stdout);
|
|
|
|
gdb_flush (gdb_stderr);
|
|
|
|
|
|
|
|
/* If there's any initialization of the target layers that must happen
|
1999-07-07 20:19:36 +00:00
|
|
|
to prepare to handle the child we're about fork, do it now...
|
1999-04-16 01:35:26 +00:00
|
|
|
*/
|
|
|
|
if (pre_trace_fun != NULL)
|
|
|
|
(*pre_trace_fun) ();
|
|
|
|
|
2001-04-08 18:26:03 +00:00
|
|
|
/* Create the child process. Note that the apparent call to vfork()
|
|
|
|
below *might* actually be a call to fork() due to the fact that
|
|
|
|
autoconf will ``#define vfork fork'' on certain platforms. */
|
1999-04-16 01:35:26 +00:00
|
|
|
if (debug_fork)
|
|
|
|
pid = fork ();
|
|
|
|
else
|
|
|
|
pid = vfork ();
|
|
|
|
|
|
|
|
if (pid < 0)
|
|
|
|
perror_with_name ("vfork");
|
|
|
|
|
|
|
|
if (pid == 0)
|
|
|
|
{
|
|
|
|
if (debug_fork)
|
|
|
|
sleep (debug_fork);
|
|
|
|
|
|
|
|
/* Run inferior in a separate process group. */
|
|
|
|
debug_setpgrp = gdb_setpgid ();
|
|
|
|
if (debug_setpgrp == -1)
|
|
|
|
perror ("setpgrp failed in child");
|
|
|
|
|
|
|
|
/* Ask the tty subsystem to switch to the one we specified earlier
|
1999-07-07 20:19:36 +00:00
|
|
|
(or to share the current terminal, if none was specified). */
|
1999-04-16 01:35:26 +00:00
|
|
|
|
|
|
|
new_tty ();
|
|
|
|
|
|
|
|
/* Changing the signal handlers for the inferior after
|
1999-07-07 20:19:36 +00:00
|
|
|
a vfork can also change them for the superior, so we don't mess
|
|
|
|
with signals here. See comments in
|
|
|
|
initialize_signals for how we get the right signal handlers
|
|
|
|
for the inferior. */
|
1999-04-16 01:35:26 +00:00
|
|
|
|
|
|
|
/* "Trace me, Dr. Memory!" */
|
|
|
|
(*traceme_fun) ();
|
|
|
|
/* The call above set this process (the "child") as debuggable
|
|
|
|
* by the original gdb process (the "parent"). Since processes
|
|
|
|
* (unlike people) can have only one parent, if you are
|
|
|
|
* debugging gdb itself (and your debugger is thus _already_ the
|
|
|
|
* controller/parent for this child), code from here on out
|
|
|
|
* is undebuggable. Indeed, you probably got an error message
|
|
|
|
* saying "not parent". Sorry--you'll have to use print statements!
|
|
|
|
*/
|
|
|
|
|
|
|
|
/* There is no execlpe call, so we have to set the environment
|
1999-07-07 20:19:36 +00:00
|
|
|
for our child in the global variable. If we've vforked, this
|
|
|
|
clobbers the parent, but environ is restored a few lines down
|
|
|
|
in the parent. By the way, yes we do need to look down the
|
|
|
|
path to find $SHELL. Rich Pixley says so, and I agree. */
|
1999-04-16 01:35:26 +00:00
|
|
|
environ = env;
|
|
|
|
|
|
|
|
/* If we decided above to start up with a shell,
|
|
|
|
* we exec the shell,
|
|
|
|
* "-c" says to interpret the next arg as a shell command
|
|
|
|
* to execute, and this command is "exec <target-program> <args>".
|
|
|
|
* "-f" means "fast startup" to the c-shell, which means
|
|
|
|
* don't do .cshrc file. Doing .cshrc may cause fork/exec
|
|
|
|
* events which will confuse debugger start-up code.
|
|
|
|
*/
|
|
|
|
if (shell)
|
|
|
|
{
|
|
|
|
execlp (shell_file, shell_file, "-c", shell_command, (char *) 0);
|
|
|
|
|
|
|
|
/* If we get here, it's an error */
|
|
|
|
fprintf_unfiltered (gdb_stderr, "Cannot exec %s: %s.\n", shell_file,
|
|
|
|
safe_strerror (errno));
|
|
|
|
gdb_flush (gdb_stderr);
|
|
|
|
_exit (0177);
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
/* Otherwise, we directly exec the target program with execvp. */
|
|
|
|
int i;
|
|
|
|
char *errstring;
|
1999-06-07 19:19:32 +00:00
|
|
|
|
1999-04-16 01:35:26 +00:00
|
|
|
execvp (exec_file, argv);
|
|
|
|
|
|
|
|
/* If we get here, it's an error */
|
|
|
|
errstring = safe_strerror (errno);
|
|
|
|
fprintf_unfiltered (gdb_stderr, "Cannot exec %s ", exec_file);
|
|
|
|
|
|
|
|
i = 1;
|
|
|
|
while (argv[i] != NULL)
|
|
|
|
{
|
|
|
|
if (i != 1)
|
|
|
|
fprintf_unfiltered (gdb_stderr, " ");
|
|
|
|
fprintf_unfiltered (gdb_stderr, "%s", argv[i]);
|
|
|
|
i++;
|
|
|
|
}
|
|
|
|
fprintf_unfiltered (gdb_stderr, ".\n");
|
|
|
|
/* This extra info seems to be useless
|
1999-07-07 20:19:36 +00:00
|
|
|
fprintf_unfiltered (gdb_stderr, "Got error %s.\n", errstring);
|
|
|
|
*/
|
1999-04-16 01:35:26 +00:00
|
|
|
gdb_flush (gdb_stderr);
|
|
|
|
_exit (0177);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Restore our environment in case a vforked child clob'd it. */
|
|
|
|
environ = save_our_env;
|
|
|
|
|
|
|
|
init_thread_list ();
|
|
|
|
|
2001-05-04 04:15:33 +00:00
|
|
|
inferior_ptid = pid_to_ptid (pid); /* Needed for wait_for_inferior stuff below */
|
1999-04-16 01:35:26 +00:00
|
|
|
|
|
|
|
/* Now that we have a child process, make it our target, and
|
|
|
|
initialize anything target-vector-specific that needs initializing. */
|
|
|
|
|
|
|
|
(*init_trace_fun) (pid);
|
|
|
|
|
|
|
|
/* We are now in the child process of interest, having exec'd the
|
|
|
|
correct program, and are poised at the first instruction of the
|
|
|
|
new program. */
|
|
|
|
|
2000-09-01 23:39:11 +00:00
|
|
|
/* Allow target dependent code to play with the new process. This might be
|
1999-04-16 01:35:26 +00:00
|
|
|
used to have target-specific code initialize a variable in the new process
|
|
|
|
prior to executing the first instruction. */
|
|
|
|
TARGET_CREATE_INFERIOR_HOOK (pid);
|
|
|
|
|
|
|
|
#ifdef SOLIB_CREATE_INFERIOR_HOOK
|
|
|
|
SOLIB_CREATE_INFERIOR_HOOK (pid);
|
|
|
|
#endif
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Accept NTRAPS traps from the inferior. */
|
|
|
|
|
|
|
|
void
|
2000-07-30 01:48:28 +00:00
|
|
|
startup_inferior (int ntraps)
|
1999-04-16 01:35:26 +00:00
|
|
|
{
|
|
|
|
int pending_execs = ntraps;
|
|
|
|
int terminal_initted;
|
|
|
|
|
|
|
|
/* The process was started by the fork that created it,
|
|
|
|
but it will have stopped one instruction after execing the shell.
|
|
|
|
Here we must get it up to actual execution of the real program. */
|
|
|
|
|
|
|
|
clear_proceed_status ();
|
|
|
|
|
|
|
|
init_wait_for_inferior ();
|
|
|
|
|
|
|
|
terminal_initted = 0;
|
|
|
|
|
|
|
|
if (STARTUP_WITH_SHELL)
|
|
|
|
inferior_ignoring_startup_exec_events = ntraps;
|
|
|
|
else
|
|
|
|
inferior_ignoring_startup_exec_events = 0;
|
|
|
|
inferior_ignoring_leading_exec_events =
|
|
|
|
target_reported_exec_events_per_exec_call () - 1;
|
|
|
|
|
|
|
|
#ifdef STARTUP_INFERIOR
|
|
|
|
STARTUP_INFERIOR (pending_execs);
|
|
|
|
#else
|
|
|
|
while (1)
|
|
|
|
{
|
2003-04-08 18:52:04 +00:00
|
|
|
/* Make wait_for_inferior be quiet */
|
2003-04-08 19:21:15 +00:00
|
|
|
stop_soon = STOP_QUIETLY;
|
1999-04-16 01:35:26 +00:00
|
|
|
wait_for_inferior ();
|
|
|
|
if (stop_signal != TARGET_SIGNAL_TRAP)
|
|
|
|
{
|
|
|
|
/* Let shell child handle its own signals in its own way */
|
|
|
|
/* FIXME, what if child has exit()ed? Must exit loop somehow */
|
|
|
|
resume (0, stop_signal);
|
|
|
|
}
|
|
|
|
else
|
|
|
|
{
|
|
|
|
/* We handle SIGTRAP, however; it means child did an exec. */
|
|
|
|
if (!terminal_initted)
|
|
|
|
{
|
|
|
|
/* Now that the child has exec'd we know it has already set its
|
1999-07-07 20:19:36 +00:00
|
|
|
process group. On POSIX systems, tcsetpgrp will fail with
|
|
|
|
EPERM if we try it before the child's setpgid. */
|
1999-04-16 01:35:26 +00:00
|
|
|
|
|
|
|
/* Set up the "saved terminal modes" of the inferior
|
1999-07-07 20:19:36 +00:00
|
|
|
based on what modes we are starting it with. */
|
1999-04-16 01:35:26 +00:00
|
|
|
target_terminal_init ();
|
|
|
|
|
|
|
|
/* Install inferior's terminal modes. */
|
|
|
|
target_terminal_inferior ();
|
|
|
|
|
|
|
|
terminal_initted = 1;
|
|
|
|
}
|
|
|
|
|
|
|
|
pending_execs = pending_execs - 1;
|
|
|
|
if (0 == pending_execs)
|
|
|
|
break;
|
|
|
|
|
|
|
|
resume (0, TARGET_SIGNAL_0); /* Just make it go on */
|
|
|
|
}
|
|
|
|
}
|
|
|
|
#endif /* STARTUP_INFERIOR */
|
2003-04-08 19:21:15 +00:00
|
|
|
stop_soon = NO_STOP_QUIETLY;
|
1999-04-16 01:35:26 +00:00
|
|
|
}
|