diff options
Diffstat (limited to 'contrib/gdb/gdb/fork-child.c')
| -rw-r--r-- | contrib/gdb/gdb/fork-child.c | 195 |
1 files changed, 76 insertions, 119 deletions
diff --git a/contrib/gdb/gdb/fork-child.c b/contrib/gdb/gdb/fork-child.c index f3504bc..aacd53c 100644 --- a/contrib/gdb/gdb/fork-child.c +++ b/contrib/gdb/gdb/fork-child.c @@ -1,39 +1,38 @@ /* Fork a Unix child process, and set up to debug it, for GDB. - Copyright 1990, 1991, 1992, 1993, 1994, 1996 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. + This file is part of GDB. -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. + 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. -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. + 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. -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. */ + 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. */ #include "defs.h" #include "gdb_string.h" #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" +#include "command.h" /* for dont_repeat () */ #include <signal.h> -#ifdef HAVE_UNISTD_H -#include <unistd.h> -#endif - -#define DEBUGGING 0 /* This just gets used as a default if we can't find SHELL */ #ifndef SHELL_FILE @@ -49,17 +48,10 @@ extern char **environ; * 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; -#if DEBUGGING - printf ("breakup_args: input = %s\n", scratch); -#endif for (;;) { @@ -97,22 +89,19 @@ breakup_args ( } -/* 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; @@ -123,13 +112,15 @@ fork_inferior (exec_file, allargs, env, traceme_fun, init_trace_fun, /* 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; - char *tryname; + 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); @@ -137,6 +128,7 @@ fork_inferior (exec_file, allargs, env, traceme_fun, init_trace_fun, * 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. */ @@ -147,14 +139,10 @@ fork_inferior (exec_file, allargs, env, traceme_fun, init_trace_fun, shell = 1; } -#if DEBUGGING - printf ("shell is %s\n", shell_file); -#endif - /* 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; + 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. */ #ifdef SHELL_COMMAND_CONCAT @@ -169,14 +157,6 @@ fork_inferior (exec_file, allargs, env, traceme_fun, init_trace_fun, { /* We're going to call execvp. Create argv */ /* Largest case: every other character is a separate arg */ -#if DEBUGGING - printf ("allocating argv, length = %d\n", - ( - (strlen (allargs) + 1) / (unsigned) 2 - + 2 - ) * sizeof (*argv) - ); -#endif argv = (char **) xmalloc (((strlen (allargs) + 1) / (unsigned) 2 + 2) * sizeof (*argv)); argv[0] = exec_file; breakup_args (allargs, &argv[1]); @@ -195,14 +175,15 @@ fork_inferior (exec_file, allargs, env, traceme_fun, init_trace_fun, 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. */ + on IRIX 4.0.1 can't deal with it. So we only quote it if we need + to. */ p = exec_file; while (1) { switch (*p) { case '\'': + case '!': case '"': case '(': case ')': @@ -234,6 +215,8 @@ fork_inferior (exec_file, allargs, env, traceme_fun, init_trace_fun, { if (*p == '\'') strcat (shell_command, "'\\''"); + else if (*p == '!') + strcat (shell_command, "\\!"); else strncat (shell_command, p, 1); } @@ -268,19 +251,18 @@ fork_inferior (exec_file, allargs, env, traceme_fun, init_trace_fun, 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... + to prepare to handle the child we're about fork, do it now... */ 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"); @@ -296,15 +278,15 @@ fork_inferior (exec_file, allargs, env, traceme_fun, init_trace_fun, 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). */ + (or to share the current terminal, if none was specified). */ new_tty (); /* Changing the signal handlers for the inferior after - 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. */ + 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. */ /* "Trace me, Dr. Memory!" */ (*traceme_fun) (); @@ -318,10 +300,10 @@ fork_inferior (exec_file, allargs, env, traceme_fun, init_trace_fun, */ /* There is no execlpe call, so we have to set the environment - 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. */ + 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. */ environ = env; /* If we decided above to start up with a shell, @@ -334,16 +316,7 @@ fork_inferior (exec_file, allargs, env, traceme_fun, init_trace_fun, */ if (shell) { -#if 0 - - /* HP change is problematic. The -f option has different meanings - for different shells. It is particularly inappropriate for - bourne shells. */ - execlp (shell_file, shell_file, "-f", "-c", shell_command, (char *) 0); -#else execlp (shell_file, shell_file, "-c", shell_command, (char *) 0); -#endif - /* If we get here, it's an error */ fprintf_unfiltered (gdb_stderr, "Cannot exec %s: %s.\n", shell_file, @@ -356,16 +329,7 @@ fork_inferior (exec_file, allargs, env, traceme_fun, init_trace_fun, /* Otherwise, we directly exec the target program with execvp. */ int i; char *errstring; -#if DEBUGGING - printf ("about to exec target, exec_file = %s\n", exec_file); - i = 0; - while (argv[i] != NULL) - { - printf ("strlen(argv[%d]) is %d\n", i, strlen (argv[i])); - printf ("argv[%d] is %s\n", i, argv[i]); - i++; - } -#endif + execvp (exec_file, argv); /* If we get here, it's an error */ @@ -382,8 +346,8 @@ fork_inferior (exec_file, allargs, env, traceme_fun, init_trace_fun, } fprintf_unfiltered (gdb_stderr, ".\n"); /* This extra info seems to be useless - fprintf_unfiltered (gdb_stderr, "Got error %s.\n", errstring); - */ + fprintf_unfiltered (gdb_stderr, "Got error %s.\n", errstring); + */ gdb_flush (gdb_stderr); _exit (0177); } @@ -394,7 +358,7 @@ fork_inferior (exec_file, allargs, env, traceme_fun, init_trace_fun, 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. */ @@ -405,7 +369,7 @@ fork_inferior (exec_file, allargs, env, traceme_fun, init_trace_fun, 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); @@ -423,14 +387,10 @@ fork_inferior (exec_file, allargs, env, traceme_fun, init_trace_fun, 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; +clone_and_follow_inferior (int child_pid, int *followed_child) { - extern int auto_solib_add; - int debugger_pid; int status; char pid_spelling[100]; /* Arbitrary but sufficient length. */ @@ -441,7 +401,7 @@ clone_and_follow_inferior (child_pid, followed_child) 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] */ @@ -459,33 +419,31 @@ clone_and_follow_inferior (child_pid, followed_child) 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 + /* Clone the debugger. 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) 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. */ + to CHILD_PID. */ if (debugger_pid != 0) { - char signal_spelling[100];/* Arbitrary but sufficient length */ + 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. + so that it remains stopped until the clone debugger can attach + to it. */ detach_breakpoints (child_pid); @@ -505,21 +463,21 @@ clone_and_follow_inferior (child_pid, followed_child) 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 + CHILD_PID. inferior_ptid 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, + /* Note that we DON'T want to actually detach from inferior_ptid, 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 + just reset inferior_ptid 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 @@ -535,7 +493,7 @@ clone_and_follow_inferior (child_pid, followed_child) 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; @@ -549,8 +507,7 @@ clone_and_follow_inferior (child_pid, followed_child) /* Accept NTRAPS traps from the inferior. */ void -startup_inferior (ntraps) - int ntraps; +startup_inferior (int ntraps) { int pending_execs = ntraps; int terminal_initted; @@ -591,11 +548,11 @@ startup_inferior (ntraps) 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. */ + 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. */ + based on what modes we are starting it with. */ target_terminal_init (); /* Install inferior's terminal modes. */ |
