/* Fork a Unix child process, and set up to debug it, for GDB.
- Copyright 1990, 91, 92, 93, 94, 1996, 1999 Free Software Foundation, Inc.
+ Copyright 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1998, 1999, 2000,
+ 2001 Free Software Foundation, Inc.
Contributed by Cygnus Support.
This file is part of GDB.
#include "frame.h" /* required by inferior.h */
#include "inferior.h"
#include "target.h"
-#include "wait.h"
+#include "gdb_wait.h"
+#include "gdb_vfork.h"
#include "gdbcore.h"
#include "terminal.h"
#include "gdbthread.h"
* the four arguments "a", "b", "c", "d".
*/
static void
-breakup_args (
- scratch,
- argv)
- char *scratch;
- char **argv;
+breakup_args (char *scratch, char **argv)
{
char *cp = scratch;
}
-/* Start an inferior Unix child process and sets inferior_pid to its pid.
+/* 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(). */
+/* This function is NOT-REENTRANT. Some of the variables have been
+ made static to ensure that they survive the vfork() call. */
+
void
-fork_inferior (exec_file, allargs, env, traceme_fun, init_trace_fun,
- pre_trace_fun, shell_file)
- char *exec_file;
- char *allargs;
- char **env;
- void (*traceme_fun) PARAMS ((void));
- void (*init_trace_fun) PARAMS ((int));
- void (*pre_trace_fun) PARAMS ((void));
- char *shell_file;
+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)
{
int pid;
char *shell_command;
/* 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;
+ static char *shell_file;
+ static char *exec_file;
char **save_our_env;
int shell = 0;
- char **argv;
+ 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. */
+ exec_file = exec_file_arg;
if (exec_file == 0)
exec_file = get_exec_file (1);
* 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)
{
/* Figure out what shell to start up the user program under. */
switch (*p)
{
case '\'':
+ case '!':
case '"':
case '(':
case ')':
{
if (*p == '\'')
strcat (shell_command, "'\\''");
+ else if (*p == '!')
+ strcat (shell_command, "\\!");
else
strncat (shell_command, p, 1);
}
if (pre_trace_fun != NULL)
(*pre_trace_fun) ();
-#if defined(USG) && !defined(HAVE_VFORK)
- pid = fork ();
-#else
+ /* 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. */
if (debug_fork)
pid = fork ();
else
pid = vfork ();
-#endif
if (pid < 0)
perror_with_name ("vfork");
init_thread_list ();
- inferior_pid = pid; /* Needed for wait_for_inferior stuff below */
+ inferior_ptid = pid_to_ptid (pid); /* Needed for wait_for_inferior stuff below */
/* Now that we have a child process, make it our target, and
initialize anything target-vector-specific that needs initializing. */
correct program, and are poised at the first instruction of the
new program. */
- /* Allow target dependant code to play with the new process. This might be
+ /* 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);
#endif
}
-/* An inferior Unix process CHILD_PID has been created by a call to
- fork() (or variants like vfork). It is presently stopped, and waiting
- to be resumed. clone_and_follow_inferior will fork the debugger,
- and that clone will "follow" (attach to) CHILD_PID. The original copy
- of the debugger will not touch CHILD_PID again.
-
- Also, the original debugger will set FOLLOWED_CHILD FALSE, while the
- clone will set it TRUE.
- */
-void
-clone_and_follow_inferior (child_pid, followed_child)
- int child_pid;
- int *followed_child;
-{
- extern int auto_solib_add;
-
- int debugger_pid;
- int status;
- char pid_spelling[100]; /* Arbitrary but sufficient length. */
-
- /* This semaphore is used to coordinate the two debuggers' handoff
- of CHILD_PID. The original debugger will detach from CHILD_PID,
- and then the clone debugger will attach to it. (It must be done
- this way because on some targets, only one process at a time can
- trace another. Thus, the original debugger must relinquish its
- tracing rights before the clone can pick them up.)
- */
-#define SEM_TALK (1)
-#define SEM_LISTEN (0)
- int handoff_semaphore[2]; /* Original "talks" to [1], clone "listens" to [0] */
- int talk_value = 99;
- int listen_value;
-
- /* Set debug_fork then attach to the child while it sleeps, to debug. */
- static int debug_fork = 0;
-
- /* 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);
-
- /* Open the semaphore pipes.
- */
- status = pipe (handoff_semaphore);
- if (status < 0)
- error ("error getting pipe for handoff semaphore");
-
- /* Clone the debugger. */
-#if defined(USG) && !defined(HAVE_VFORK)
- debugger_pid = fork ();
-#else
- if (debug_fork)
- debugger_pid = fork ();
- else
- debugger_pid = vfork ();
-#endif
-
- if (debugger_pid < 0)
- perror_with_name ("fork");
-
- /* Are we the original debugger? If so, we must relinquish all claims
- to CHILD_PID. */
- if (debugger_pid != 0)
- {
- char signal_spelling[100]; /* Arbitrary but sufficient length */
-
- /* Detach from CHILD_PID. Deliver a "stop" signal when we do, though,
- so that it remains stopped until the clone debugger can attach
- to it.
- */
- detach_breakpoints (child_pid);
-
- sprintf (signal_spelling, "%d", target_signal_to_host (TARGET_SIGNAL_STOP));
- target_require_detach (child_pid, signal_spelling, 1);
-
- /* Notify the clone debugger that it should attach to CHILD_PID. */
- write (handoff_semaphore[SEM_TALK], &talk_value, sizeof (talk_value));
-
- *followed_child = 0;
- }
-
- /* We're the child. */
- else
- {
- if (debug_fork)
- sleep (debug_fork);
-
- /* The child (i.e., the cloned debugger) must now attach to
- CHILD_PID. inferior_pid is presently set to the parent process
- of the fork, while CHILD_PID should be the child process of the
- fork.
-
- Wait until the original debugger relinquishes control of CHILD_PID,
- though.
- */
- read (handoff_semaphore[SEM_LISTEN], &listen_value, sizeof (listen_value));
-
- /* Note that we DON'T want to actually detach from inferior_pid,
- because that would allow it to run free. The original
- debugger wants to retain control of the process. So, we
- just reset inferior_pid to CHILD_PID, and then ensure that all
- breakpoints are really set in CHILD_PID.
- */
- target_mourn_inferior ();
-
- /* Ask the tty subsystem to switch to the one we specified earlier
- (or to share the current terminal, if none was specified). */
-
- new_tty ();
-
- dont_repeat ();
- sprintf (pid_spelling, "%d", child_pid);
- target_require_attach (pid_spelling, 1);
-
- /* Perform any necessary cleanup, after attachment. (This form
- of attaching can behave differently on some targets than the
- standard method, where a process formerly not under debugger
- control was suddenly attached to..)
- */
- target_post_follow_inferior_by_clone ();
-
- *followed_child = 1;
- }
-
- /* Discard the handoff sempahore. */
- (void) close (handoff_semaphore[SEM_LISTEN]);
- (void) close (handoff_semaphore[SEM_TALK]);
-}
-
/* Accept NTRAPS traps from the inferior. */
void
-startup_inferior (ntraps)
- int ntraps;
+startup_inferior (int ntraps)
{
int pending_execs = ntraps;
int terminal_initted;
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