/* Fork a Unix child process, and set up to debug it, for GDB.
- Copyright (C) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1998, 1999, 2000,
- 2001, 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
+ Copyright (C) 1990-2013 Free Software Foundation, Inc.
Contributed by Cygnus Support.
#include "defs.h"
#include "gdb_string.h"
-#include "frame.h" /* required by inferior.h */
#include "inferior.h"
+#include "terminal.h"
#include "target.h"
#include "gdb_wait.h"
#include "gdb_vfork.h"
#include "command.h" /* for dont_repeat () */
#include "gdbcmd.h"
#include "solib.h"
+#include "filestuff.h"
#include <signal.h>
static void
breakup_args (char *scratch, char **argv)
{
- char *cp = scratch;
+ char *cp = scratch, *tmp;
for (;;)
{
*argv++ = cp;
/* Scan for next arg separator. */
- cp = strchr (cp, ' ');
- if (cp == NULL)
- cp = strchr (cp, '\t');
- if (cp == NULL)
- cp = strchr (cp, '\n');
+ tmp = strchr (cp, ' ');
+ if (tmp == NULL)
+ tmp = strchr (cp, '\t');
+ if (tmp == NULL)
+ tmp = strchr (cp, '\n');
/* No separators => end of string => break. */
- if (cp == NULL)
+ if (tmp == NULL)
break;
+ cp = tmp;
/* Replace the separator with a terminator. */
*cp++ = '\0';
pid. 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. EXEC_FUN is the exec(2) function to use, or NULL for the default
one. */
/* This function is NOT reentrant. Some of the variables have been
int
fork_inferior (char *exec_file_arg, char *allargs, char **env,
void (*traceme_fun) (void), void (*init_trace_fun) (int),
- void (*pre_trace_fun) (void), char *shell_file_arg)
+ void (*pre_trace_fun) (void), char *shell_file_arg,
+ void (*exec_fun)(const char *file, char * const *argv,
+ char * const *env))
{
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. */
+ /* 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. */
int shell = 0;
static char **argv;
const char *inferior_io_terminal = get_inferior_io_terminal ();
+ struct inferior *inf;
+ int i;
+ int save_errno;
/* If no exec file handed to us, get it from the exec-file command
-- with a good, common error message if none is specified. */
if (exec_file == 0)
exec_file = get_exec_file (1);
- /* STARTUP_WITH_SHELL is defined in inferior.h. If 0,e we'll just
- do a fork/exec, no shell, so don't bother figuring out what
- shell. */
+ /* 'startup_with_shell' is declared in inferior.h and bound to the
+ "set startup-with-shell" option. If 0, we'll just do a
+ fork/exec, no shell, so don't bother figuring out what shell. */
shell_file = shell_file_arg;
- if (STARTUP_WITH_SHELL)
+ if (startup_with_shell)
{
/* Figure out what shell to start up the user program under. */
if (shell_file == NULL)
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 '. */
- len = 5 + 4 * strlen (exec_file) + 1 + strlen (allargs) + 1 + /*slop */ 12;
- if (exec_wrapper)
- len += strlen (exec_wrapper) + 1;
-
- shell_command = (char *) alloca (len);
- shell_command[0] = '\0';
-
if (!shell)
{
/* We're going to call execvp. Create argument vector.
assuming that every other character is a separate
argument. */
int argc = (strlen (allargs) + 1) / 2 + 2;
- argv = (char **) xmalloc (argc * sizeof (*argv));
+
+ argv = (char **) alloca (argc * sizeof (*argv));
argv[0] = exec_file;
breakup_args (allargs, &argv[1]);
}
else
{
/* We're going to call a shell. */
-
+ char *shell_command;
+ int len;
char *p;
int need_to_quote;
const int escape_bang = escape_bang_in_quoted_argument (shell_file);
+ /* 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 '. */
+ len = 5 + 4 * strlen (exec_file) + 1 + strlen (allargs) + 1 + /*slop */ 12;
+ if (exec_wrapper)
+ len += strlen (exec_wrapper) + 1;
+
+ shell_command = (char *) alloca (len);
+ shell_command[0] = '\0';
+
strcat (shell_command, "exec ");
/* Add any exec wrapper. That may be a program name with arguments, so
strcat (shell_command, " ");
strcat (shell_command, allargs);
- }
- /* On some systems an exec will fail if the executable is open. */
- close_exec_file ();
+ /* 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>". */
+ argv = (char **) alloca (4 * sizeof (char *));
+ argv[0] = shell_file;
+ argv[1] = "-c";
+ argv[2] = shell_command;
+ argv[3] = (char *) 0;
+ }
/* Retain a copy of our environment variables, since the child will
replace the value of environ and if we're vforked, we have to
/* 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. */
+ the parent and child flushing the same data after the fork. */
gdb_flush (gdb_stdout);
gdb_flush (gdb_stderr);
if (pid == 0)
{
+ close_most_fds ();
+
if (debug_fork)
sleep (debug_fork);
in a separate process group. */
debug_setpgrp = gdb_setpgid ();
if (debug_setpgrp == -1)
- perror ("setpgrp failed in child");
+ perror (_("setpgrp failed in child"));
}
/* Ask the tty subsystem to switch to the one we specified
initialize_signals for how we get the right signal handlers
for the inferior. */
- /* "Trace me, Dr. Memory!" */
+ /* "Trace me, Dr. Memory!" */
(*traceme_fun) ();
/* The call above set this process (the "child") as debuggable
path to find $SHELL. Rich Pixley says so, and I agree. */
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>". */
- 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);
- }
+ if (exec_fun != NULL)
+ (*exec_fun) (argv[0], argv, env);
else
- {
- /* Otherwise, we directly exec the target program with
- execvp. */
- int i;
- char *errstring;
-
- 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");
-#if 0
- /* This extra info seems to be useless. */
- fprintf_unfiltered (gdb_stderr, "Got error %s.\n", errstring);
-#endif
- gdb_flush (gdb_stderr);
- _exit (0177);
- }
+ execvp (argv[0], argv);
+
+ /* If we get here, it's an error. */
+ save_errno = errno;
+ fprintf_unfiltered (gdb_stderr, "Cannot exec %s", exec_file);
+ for (i = 1; argv[i] != NULL; i++)
+ fprintf_unfiltered (gdb_stderr, " %s", argv[i]);
+ fprintf_unfiltered (gdb_stderr, ".\n");
+ fprintf_unfiltered (gdb_stderr, "Error: %s\n",
+ safe_strerror (save_errno));
+ gdb_flush (gdb_stderr);
+ _exit (0177);
}
/* Restore our environment in case a vforked child clob'd it. */
environ = save_our_env;
- init_thread_list ();
+ if (!have_inferiors ())
+ init_thread_list ();
+
+ inf = current_inferior ();
- add_inferior (pid);
+ inferior_appeared (inf, pid);
/* Needed for wait_for_inferior stuff below. */
inferior_ptid = pid_to_ptid (pid);
+ new_tty_postfork ();
+
/* We have something that executes now. We'll be running through
the shell at this point, but the pid shouldn't change. Targets
supporting MT should fill this task's ptid with more data as soon
{
int pending_execs = ntraps;
int terminal_initted = 0;
+ ptid_t resume_ptid;
+
+ if (startup_with_shell)
+ {
+ /* One trap extra for exec'ing the shell. */
+ pending_execs++;
+ }
+
+ if (target_supports_multi_process ())
+ resume_ptid = pid_to_ptid (ptid_get_pid (inferior_ptid));
+ else
+ resume_ptid = minus_one_ptid;
/* The process was started by the fork that created it, but it will
have stopped one instruction after execing the shell. Here we
while (1)
{
- int resume_signal = TARGET_SIGNAL_0;
- ptid_t resume_ptid;
+ enum gdb_signal resume_signal = GDB_SIGNAL_0;
ptid_t event_ptid;
struct target_waitstatus ws;
memset (&ws, 0, sizeof (ws));
- event_ptid = target_wait (pid_to_ptid (-1), &ws);
+ event_ptid = target_wait (resume_ptid, &ws, 0);
if (ws.kind == TARGET_WAITKIND_IGNORE)
/* The inferior didn't really stop, keep waiting. */
target_terminal_ours ();
target_mourn_inferior ();
error (_("During startup program terminated with signal %s, %s."),
- target_signal_to_name (ws.value.sig),
- target_signal_to_string (ws.value.sig));
+ gdb_signal_to_name (ws.value.sig),
+ gdb_signal_to_string (ws.value.sig));
return;
case TARGET_WAITKIND_EXITED:
case TARGET_WAITKIND_EXECD:
/* Handle EXEC signals as if they were SIGTRAP signals. */
xfree (ws.value.execd_pathname);
- resume_signal = TARGET_SIGNAL_TRAP;
+ resume_signal = GDB_SIGNAL_TRAP;
switch_to_thread (event_ptid);
break;
break;
}
- /* In all-stop mode, resume all threads. */
- if (!non_stop)
- resume_ptid = pid_to_ptid (-1);
- else
- resume_ptid = event_ptid;
-
- if (resume_signal != TARGET_SIGNAL_TRAP)
+ if (resume_signal != GDB_SIGNAL_TRAP)
{
/* Let shell child handle its own signals in its own way. */
target_resume (resume_ptid, 0, resume_signal);
break;
/* Just make it go on. */
- target_resume (resume_ptid, 0, TARGET_SIGNAL_0);
+ target_resume (resume_ptid, 0, GDB_SIGNAL_0);
}
}
/* Mark all threads non-executing. */
- set_executing (pid_to_ptid (-1), 0);
-
- stop_pc = read_pc ();
+ set_executing (resume_ptid, 0);
}
/* Implement the "unset exec-wrapper" command. */
exec_wrapper = NULL;
}
+static void
+show_startup_with_shell (struct ui_file *file, int from_tty,
+ struct cmd_list_element *c, const char *value)
+{
+ fprintf_filtered (file,
+ _("Use of shell to start subprocesses is %s.\n"),
+ value);
+}
+
+/* Provide a prototype to silence -Wmissing-prototypes. */
+extern initialize_file_ftype _initialize_fork_child;
+
void
_initialize_fork_child (void)
{
add_cmd ("exec-wrapper", class_run, unset_exec_wrapper_command,
_("Disable use of an execution wrapper."),
&unsetlist);
+
+ add_setshow_boolean_cmd ("startup-with-shell", class_support,
+ &startup_with_shell, _("\
+Set use of shell to start subprocesses. The default is on."), _("\
+Show use of shell to start subprocesses."), NULL,
+ NULL,
+ show_startup_with_shell,
+ &setlist, &showlist);
}