* fork-child.c: Update copyright year. Fix coding style.

This commit is contained in:
Mark Kettenis 2004-09-30 20:15:39 +00:00
parent 982526a134
commit 74a4fe3270
2 changed files with 103 additions and 104 deletions

View file

@ -1,3 +1,7 @@
2004-09-30 Mark Kettenis <kettenis@chello.nl>
* fork-child.c: Update copyright year. Fix coding style.
2004-09-29 Mark Kettenis <kettenis@gnu.org>
* defs.h (msavestring, mstrsave): Remove prototypes.

View file

@ -1,6 +1,8 @@
/* Fork a Unix child process, and set up to debug it, for GDB.
Copyright 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1998, 1999, 2000,
2001 Free Software Foundation, Inc.
Copyright 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1998, 1999,
2000, 2001, 2004 Free Software Foundation, Inc.
Contributed by Cygnus Support.
This file is part of GDB.
@ -34,19 +36,18 @@
#include <signal.h>
/* This just gets used as a default if we can't find SHELL */
/* 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".
*/
/* Break up SCRATCH into an argument vector suitable for passing to
execvp and store it in ARGV. 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
breakup_args (char *scratch, char **argv)
{
@ -54,49 +55,45 @@ breakup_args (char *scratch, char **argv)
for (;;)
{
/* Scan past leading separators */
while (*cp == ' ' || *cp == '\t' || *cp == '\n')
{
cp++;
}
cp++;
/* Break if at end of string */
/* Break if at end of string. */
if (*cp == '\0')
break;
/* Take an arg */
/* Take an arg. */
*argv++ = cp;
/* Scan for next arg separator */
/* 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 */
/* No separators => end of string => break. */
if (cp == NULL)
break;
/* Replace the separator with a terminator */
/* Replace the separator with a terminator. */
*cp++ = '\0';
}
/* execv requires a null-terminated arg vector */
/* Null-terminate the vector. */
*argv = NULL;
}
/* When executing a command under the given shell, return non-zero
if the '!' character should be escaped when embedded in a quoted
/* When executing a command under the given shell, return non-zero if
the '!' character should be escaped when embedded in a quoted
command-line argument. */
static int
escape_bang_in_quoted_argument (const char *shell_file)
{
const int shell_file_len = strlen (shell_file);
/* Bang should be escaped only in C Shells. For now, simply check
that the shell name ends with 'csh', which covers at least csh
and tcsh. This should be good enough for now. */
@ -112,14 +109,14 @@ escape_bang_in_quoted_argument (const char *shell_file)
return 0;
}
/* Start an inferior Unix child process and sets inferior_ptid to its 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. Errors reported with error(). */
/* Start an inferior Unix child process and sets inferior_ptid to its
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. */
/* This function is NOT-REENTRANT. Some of the variables have been
made static to ensure that they survive the vfork() call. */
/* This function is NOT reentrant. Some of the variables have been
made static to ensure that they survive the vfork call. */
void
fork_inferior (char *exec_file_arg, char *allargs, char **env,
@ -141,20 +138,19 @@ fork_inferior (char *exec_file_arg, char *allargs, char **env,
int shell = 0;
static char **argv;
/* 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 no exec file handed to us, get it from the exec-file command
-- with a good, common error message if none is specified. */
exec_file = exec_file_arg;
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.
*/
/* 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. */
shell_file = shell_file_arg;
if (STARTUP_WITH_SHELL)
{
/* Figure out what shell to start up the user program under. */
/* Figure out what shell to start up the user program under. */
if (shell_file == NULL)
shell_file = getenv ("SHELL");
if (shell_file == NULL)
@ -162,9 +158,9 @@ fork_inferior (char *exec_file_arg, char *allargs, char **env,
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 '. */
/* 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 desired, concat something onto the front of ALLARGS.
SHELL_COMMAND is the result. */
@ -178,17 +174,18 @@ fork_inferior (char *exec_file_arg, char *allargs, char **env,
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));
/* We're going to call execvp. Create argument vector.
Calculate an upper bound on the length of the vector by
assuming that every other character is a separate
argument. */
int argc = (strlen (allargs) + 1) / 2 + 2;
argv = (char **) xmalloc (argc * sizeof (*argv));
argv[0] = exec_file;
breakup_args (allargs, &argv[1]);
}
else
{
/* We're going to call a shell */
/* We're going to call a shell. */
/* Now add exec_file, quoting as necessary. */
@ -198,9 +195,9 @@ fork_inferior (char *exec_file_arg, char *allargs, char **env,
strcat (shell_command, "exec ");
/* Quoting in this style is said to work with all shells. But csh
on IRIX 4.0.1 can't deal with it. So we only quote it if we need
to. */
/* Quoting in this style is said to work with all shells. But
csh on IRIX 4.0.1 can't deal with it. So we only quote it if
we need to. */
p = exec_file;
while (1)
{
@ -251,32 +248,29 @@ fork_inferior (char *exec_file_arg, char *allargs, char **env,
strcat (shell_command, " ");
strcat (shell_command, allargs);
}
/* exec is said to fail if the executable is open. */
/* On some systems an exec will 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
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. */
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
to prepare to handle the child we're about fork, do it now...
*/
/* If there's any initialization of the target layers that must
happen to prepare to handle the child we're about fork, do it
now... */
if (pre_trace_fun != NULL)
(*pre_trace_fun) ();
@ -301,9 +295,9 @@ fork_inferior (char *exec_file_arg, char *allargs, char **env,
if (debug_setpgrp == -1)
perror ("setpgrp failed in child");
/* Ask the tty subsystem to switch to the one we specified earlier
(or to share the current terminal, if none was specified). */
/* Ask the tty subsystem to switch to the one we specified
earlier (or to share the current terminal, if none was
specified). */
new_tty ();
/* Changing the signal handlers for the inferior after
@ -314,14 +308,15 @@ fork_inferior (char *exec_file_arg, char *allargs, char **env,
/* "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!
*/
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
for our child in the global variable. If we've vforked, this
@ -330,19 +325,17 @@ fork_inferior (char *exec_file_arg, char *allargs, char **env,
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>".
* "-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 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 */
/* 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);
@ -350,13 +343,14 @@ fork_inferior (char *exec_file_arg, char *allargs, char **env,
}
else
{
/* Otherwise, we directly exec the target program with execvp. */
/* 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 */
/* If we get here, it's an error. */
errstring = safe_strerror (errno);
fprintf_unfiltered (gdb_stderr, "Cannot exec %s ", exec_file);
@ -369,9 +363,10 @@ fork_inferior (char *exec_file_arg, char *allargs, char **env,
i++;
}
fprintf_unfiltered (gdb_stderr, ".\n");
/* This extra info seems to be useless
fprintf_unfiltered (gdb_stderr, "Got error %s.\n", errstring);
*/
#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);
}
@ -382,20 +377,21 @@ fork_inferior (char *exec_file_arg, char *allargs, char **env,
init_thread_list ();
inferior_ptid = pid_to_ptid (pid); /* Needed for wait_for_inferior stuff below */
/* Needed for wait_for_inferior stuff below. */
inferior_ptid = pid_to_ptid (pid);
/* Now that we have a child process, make it our target, and
initialize anything target-vector-specific that needs initializing. */
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. */
/* Allow target dependent code to play with the new process. This might be
used to have target-specific code initialize a variable in the new process
prior to executing the first instruction. */
/* Allow target dependent code to play with the new process. This
might be 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
@ -409,18 +405,16 @@ void
startup_inferior (int ntraps)
{
int pending_execs = ntraps;
int terminal_initted;
int terminal_initted = 0;
/* 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. */
/* 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
@ -430,13 +424,14 @@ startup_inferior (int ntraps)
while (1)
{
/* Make wait_for_inferior be quiet */
/* Make wait_for_inferior be quiet. */
stop_soon = STOP_QUIETLY;
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 */
/* Let shell child handle its own signals in its own way.
FIXME: what if child has exited? Must exit loop
somehow. */
resume (0, stop_signal);
}
else
@ -444,9 +439,10 @@ startup_inferior (int ntraps)
/* 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
process group. On POSIX systems, tcsetpgrp will fail with
EPERM if we try it before the child's setpgid. */
/* Now that the child has exec'd we know it has already
set its process group. On POSIX systems, tcsetpgrp
will fail with EPERM if we try it before the child's
setpgid. */
/* Set up the "saved terminal modes" of the inferior
based on what modes we are starting it with. */
@ -458,11 +454,10 @@ startup_inferior (int ntraps)
terminal_initted = 1;
}
pending_execs = pending_execs - 1;
if (0 == pending_execs)
if (--pending_execs == 0)
break;
resume (0, TARGET_SIGNAL_0); /* Just make it go on */
resume (0, TARGET_SIGNAL_0); /* Just make it go on. */
}
}
stop_soon = NO_STOP_QUIETLY;