/* trap.c -- Not the trap command, but useful functions for manipulating
those objects. The trap command is in builtins/trap.def. */
-/* Copyright (C) 1987, 1991 Free Software Foundation, Inc.
+/* Copyright (C) 1987-2005 Free Software Foundation, Inc.
This file is part of GNU Bash, the Bourne Again SHell.
Bash 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 1, or (at your option) any later
+ Software Foundation; either version 2, or (at your option) any later
version.
Bash is distributed in the hope that it will be useful, but WITHOUT ANY
You should have received a copy of the GNU General Public License along
with Bash; see the file COPYING. If not, write to the Free Software
- Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
+ Foundation, 59 Temple Place, Suite 330, Boston, MA 02111 USA. */
#include "config.h"
#include "bashansi.h"
#include <stdio.h>
+#include <errno.h>
+
+#include "bashintl.h"
#include "trap.h"
#include "shell.h"
+#include "flags.h"
+#include "input.h" /* for save_token_state, restore_token_state */
#include "signames.h"
+#include "builtins.h"
#include "builtins/common.h"
+#include "builtins/builtext.h"
+
+#ifndef errno
+extern int errno;
+#endif
/* Flags which describe the current handling state of a signal. */
#define SIG_INHERITED 0x0 /* Value inherited from parent. */
#define SIG_CHANGED 0x20 /* Trap value changed in trap handler. */
#define SIG_IGNORED 0x40 /* The signal is currently being ignored. */
+#define SPECIAL_TRAP(s) ((s) == EXIT_TRAP || (s) == DEBUG_TRAP || (s) == ERROR_TRAP || (s) == RETURN_TRAP)
+
/* An array of such flags, one for each signal, describing what the
shell will do with a signal. DEBUG_TRAP == NSIG; some code below
assumes this. */
-static int sigmodes[NSIG+1];
+static int sigmodes[BASH_NSIG];
+
+static void free_trap_command __P((int));
+static void change_signal __P((int, char *));
+
+static void get_original_signal __P((int));
+
+static int _run_trap_internal __P((int, char *));
-static void change_signal (), restore_signal ();
+static void reset_signal __P((int));
+static void restore_signal __P((int));
+static void reset_or_restore_signal_handlers __P((sh_resetsig_func_t *));
/* Variables used here but defined in other files. */
-extern int interactive_shell, interactive;
extern int interrupt_immediately;
extern int last_command_exit_value;
extern int line_number;
+extern char *this_command_name;
+extern sh_builtin_func_t *this_shell_builtin;
+extern procenv_t wait_intr_buf;
+extern int return_catch_flag, return_catch_value;
+extern int subshell_level;
+
/* The list of things to do originally, before we started trapping. */
SigHandler *original_signals[NSIG];
DEFAULT_SIG, which means do whatever you were going to do before
you were so rudely interrupted, or IGNORE_SIG, which says ignore
this signal. */
-char *trap_list[NSIG+1];
+char *trap_list[BASH_NSIG];
/* A bitmap of signals received for which we have trap handlers. */
int pending_traps[NSIG];
trap command (e.g., when `return' is executed in the trap command). */
int running_trap;
-/* The value of line_number when the trap started executing, since
- parse_and_execute resets it to 1 and the trap command might want
- it. */
-int trap_line_number;
+/* Set to last_command_exit_value before running a trap. */
+int trap_saved_exit_value;
+
+/* The (trapped) signal received while executing in the `wait' builtin */
+int wait_signal_received;
/* A value which can never be the target of a trap handler. */
#define IMPOSSIBLE_TRAP_HANDLER (SigHandler *)initialize_traps
{
register int i;
- trap_list[EXIT_TRAP] = trap_list[DEBUG_TRAP] = (char *)NULL;
- sigmodes[EXIT_TRAP] = sigmodes[DEBUG_TRAP] = SIG_INHERITED;
+ trap_list[EXIT_TRAP] = trap_list[DEBUG_TRAP] = trap_list[ERROR_TRAP] = trap_list[RETURN_TRAP] = (char *)NULL;
+ sigmodes[EXIT_TRAP] = sigmodes[DEBUG_TRAP] = sigmodes[ERROR_TRAP] = sigmodes[RETURN_TRAP] = SIG_INHERITED;
original_signals[EXIT_TRAP] = IMPOSSIBLE_TRAP_HANDLER;
for (i = 1; i < NSIG; i++)
set_signal_handler (SIGINT, original_signals[SIGINT]);
sigmodes[SIGINT] |= SIG_SPECIAL;
+#if defined (__BEOS__)
+ /* BeOS sets SIGINT to SIG_IGN! */
+ original_signals[SIGINT] = SIG_DFL;
+#endif
+
original_signals[SIGQUIT] =
(SigHandler *) set_signal_handler (SIGQUIT, SIG_DFL);
set_signal_handler (SIGQUIT, original_signals[SIGQUIT]);
}
}
+#ifdef INCLUDE_UNUSED
+/* Return a printable representation of the trap handler for SIG. */
+static char *
+trap_handler_string (sig)
+ int sig;
+{
+ if (trap_list[sig] == (char *)DEFAULT_SIG)
+ return "DEFAULT_SIG";
+ else if (trap_list[sig] == (char *)IGNORE_SIG)
+ return "IGNORE_SIG";
+ else if (trap_list[sig] == (char *)IMPOSSIBLE_TRAP_HANDLER)
+ return "IMPOSSIBLE_TRAP_HANDLER";
+ else if (trap_list[sig])
+ return trap_list[sig];
+ else
+ return "NULL";
+}
+#endif
+
/* Return the print name of this signal. */
char *
signal_name (sig)
char *ret;
/* on cygwin32, signal_names[sig] could be null */
- ret = (sig > NSIG || sig < 0) ? "bad signal number" : signal_names[sig];
- if (ret == NULL)
- ret = "unrecognized signal number";
+ ret = (sig >= BASH_NSIG || sig < 0 || signal_names[sig] == NULL)
+ ? _("invalid signal number")
+ : signal_names[sig];
+
return ret;
}
then (int)2 is returned. Return NO_SIG if STRING doesn't
contain a valid signal descriptor. */
int
-decode_signal (string)
+decode_signal (string, flags)
char *string;
+ int flags;
{
- long sig;
+ intmax_t sig;
+ char *name;
if (legal_number (string, &sig))
- return ((sig >= 0 && sig <= NSIG) ? (int)sig : NO_SIG);
+ return ((sig >= 0 && sig < NSIG) ? (int)sig : NO_SIG);
/* A leading `SIG' may be omitted. */
- for (sig = 0; sig <= NSIG; sig++)
- if (strcasecmp (string, signal_names[sig]) == 0 ||
- (STREQN (signal_names[sig], "SIG", 3) &&
- strcasecmp (string, &(signal_names[sig])[3]) == 0))
- return ((int)sig);
+ for (sig = 0; sig < BASH_NSIG; sig++)
+ {
+ name = signal_names[sig];
+ if (name == 0 || name[0] == '\0')
+ continue;
+
+ /* Check name without the SIG prefix first case sensitivly or
+ insensitively depending on whether flags includes DSIG_NOCASE */
+ if (STREQN (name, "SIG", 3))
+ {
+ name += 3;
+
+ if ((flags & DSIG_NOCASE) && strcasecmp (string, name) == 0)
+ return ((int)sig);
+ else if ((flags & DSIG_NOCASE) == 0 && strcmp (string, name) == 0)
+ return ((int)sig);
+ /* If we can't use the `SIG' prefix to match, punt on this
+ name now. */
+ else if ((flags & DSIG_SIGPREFIX) == 0)
+ continue;
+ }
+
+ /* Check name with SIG prefix case sensitively or insensitively
+ depending on whether flags includes DSIG_NOCASE */
+ name = signal_names[sig];
+ if ((flags & DSIG_NOCASE) && strcasecmp (string, name) == 0)
+ return ((int)sig);
+ else if ((flags & DSIG_NOCASE) == 0 && strcmp (string, name) == 0)
+ return ((int)sig);
+ }
return (NO_SIG);
}
run_pending_traps ()
{
register int sig;
- int old_exit_value;
+ int old_exit_value, *token_state;
if (catch_flag == 0) /* simple optimization */
return;
for (sig = 1; sig < NSIG; sig++)
{
/* XXX this could be made into a counter by using
- while (pending_traps[sig]--) instead of the if statement. */
+ while (pending_traps[sig]--) instead of the if statement. */
if (pending_traps[sig])
{
#if defined (HAVE_POSIX_SIGNALS)
run_interrupt_trap ();
CLRINTERRUPT;
}
+ else if (trap_list[sig] == (char *)DEFAULT_SIG ||
+ trap_list[sig] == (char *)IGNORE_SIG ||
+ trap_list[sig] == (char *)IMPOSSIBLE_TRAP_HANDLER)
+ {
+ /* This is possible due to a race condition. Say a bash
+ process has SIGTERM trapped. A subshell is spawned
+ using { list; } & and the parent does something and kills
+ the subshell with SIGTERM. It's possible for the subshell
+ to set pending_traps[SIGTERM] to 1 before the code in
+ execute_cmd.c eventually calls restore_original_signals
+ to reset the SIGTERM signal handler in the subshell. The
+ next time run_pending_traps is called, pending_traps[SIGTERM]
+ will be 1, but the trap handler in trap_list[SIGTERM] will
+ be invalid (probably DEFAULT_SIG, but it could be IGNORE_SIG).
+ Unless we catch this, the subshell will dump core when
+ trap_list[SIGTERM] == DEFAULT_SIG, because DEFAULT_SIG is
+ usually 0x0. */
+ internal_warning (_("run_pending_traps: bad value in trap_list[%d]: %p"),
+ sig, trap_list[sig]);
+ if (trap_list[sig] == (char *)DEFAULT_SIG)
+ {
+ internal_warning (_("run_pending_traps: signal handler is SIG_DFL, resending %d (%s) to myself"), sig, signal_name (sig));
+ kill (getpid (), sig);
+ }
+ }
else
- parse_and_execute (savestring (trap_list[sig]), "trap", SEVAL_NONINT|SEVAL_NOHIST);
+ {
+ token_state = save_token_state ();
+ parse_and_execute (savestring (trap_list[sig]), "trap", SEVAL_NONINT|SEVAL_NOHIST);
+ restore_token_state (token_state);
+ free (token_state);
+ }
pending_traps[sig] = 0;
trap_handler (sig)
int sig;
{
+ int oerrno;
+
if ((sig >= NSIG) ||
(trap_list[sig] == (char *)DEFAULT_SIG) ||
(trap_list[sig] == (char *)IGNORE_SIG))
- programming_error ("trap_handler: bad signal %d", sig);
+ programming_error (_("trap_handler: bad signal %d"), sig);
else
{
+ oerrno = errno;
#if defined (MUST_REINSTALL_SIGHANDLERS)
set_signal_handler (sig, trap_handler);
#endif /* MUST_REINSTALL_SIGHANDLERS */
catch_flag = 1;
pending_traps[sig]++;
+ if (interrupt_immediately && this_shell_builtin && (this_shell_builtin == wait_builtin))
+ {
+ wait_signal_received = sig;
+ longjmp (wait_intr_buf, 1);
+ }
+
if (interrupt_immediately)
run_pending_traps ();
+
+ errno = oerrno;
}
SIGRETURN (0);
}
#endif
-/* Make COMMAND_STRING be executed when SIGCHLD is caught iff the current
- SIGCHLD trap handler is DEFAULT_SIG. */
+/* Make COMMAND_STRING be executed when SIGCHLD is caught iff SIGCHLD
+ is not already trapped. */
void
maybe_set_sigchld_trap (command_string)
char *command_string;
set_signal (DEBUG_TRAP, command);
}
+void
+set_error_trap (command)
+ char *command;
+{
+ set_signal (ERROR_TRAP, command);
+}
+
+void
+set_return_trap (command)
+ char *command;
+{
+ set_signal (RETURN_TRAP, command);
+}
+
#ifdef INCLUDE_UNUSED
void
set_sigint_trap (command)
int sig;
char *string;
{
- if (sig == DEBUG_TRAP || sig == EXIT_TRAP)
+ if (SPECIAL_TRAP (sig))
{
change_signal (sig, savestring (string));
if (sig == EXIT_TRAP && interactive == 0)
restore_default_signal (sig)
int sig;
{
- if (sig == DEBUG_TRAP || sig == EXIT_TRAP)
+ if (SPECIAL_TRAP (sig))
{
- if ((sig != DEBUG_TRAP) || (sigmodes[sig] & SIG_INPROGRESS) == 0)
+ if ((sig != DEBUG_TRAP && sig != ERROR_TRAP && sig != RETURN_TRAP) ||
+ (sigmodes[sig] & SIG_INPROGRESS) == 0)
free_trap_command (sig);
trap_list[sig] = (char *)NULL;
sigmodes[sig] &= ~SIG_TRAPPED;
ignore_signal (sig)
int sig;
{
- if ((sig == EXIT_TRAP || sig == DEBUG_TRAP) && ((sigmodes[sig] & SIG_IGNORED) == 0))
+ if (SPECIAL_TRAP (sig) && ((sigmodes[sig] & SIG_IGNORED) == 0))
{
change_signal (sig, (char *)IGNORE_SIG);
return;
run_exit_trap ()
{
char *trap_command;
- int code, old_exit_value;
+ int code, function_code, retval;
- old_exit_value = last_command_exit_value;
+ trap_saved_exit_value = last_command_exit_value;
+ function_code = 0;
/* Run the trap only if signal 0 is trapped and not ignored, and we are not
currently running in the trap handler (call to exit in the list of
sigmodes[EXIT_TRAP] &= ~SIG_TRAPPED;
sigmodes[EXIT_TRAP] |= SIG_INPROGRESS;
+ retval = trap_saved_exit_value;
+ running_trap = 1;
+
code = setjmp (top_level);
- if (code == 0)
+ /* If we're in a function, make sure return longjmps come here, too. */
+ if (return_catch_flag)
+ function_code = setjmp (return_catch);
+
+ if (code == 0 && function_code == 0)
{
reset_parser ();
parse_and_execute (trap_command, "exit trap", SEVAL_NONINT|SEVAL_NOHIST);
}
+ else if (code == ERREXIT)
+ retval = last_command_exit_value;
else if (code == EXITPROG)
- return (last_command_exit_value);
+ retval = last_command_exit_value;
+ else if (function_code != 0)
+ retval = return_catch_value;
else
- return (old_exit_value);
+ retval = trap_saved_exit_value;
+
+ running_trap = 0;
+ return retval;
}
- return (old_exit_value);
+ return (trap_saved_exit_value);
}
void
}
/* Run a trap command for SIG. SIG is one of the signals the shell treats
- specially. */
-static void
+ specially. Returns the exit status of the executed trap command list. */
+static int
_run_trap_internal (sig, tag)
int sig;
char *tag;
{
char *trap_command, *old_trap;
- int old_exit_value, old_line_number;
+ int trap_exit_value, *token_state;
+ int save_return_catch_flag, function_code;
+ procenv_t save_return_catch;
+ trap_exit_value = function_code = 0;
/* Run the trap only if SIG is trapped and not ignored, and we are not
currently executing in the trap handler. */
if ((sigmodes[sig] & SIG_TRAPPED) && ((sigmodes[sig] & SIG_IGNORED) == 0) &&
trap_command = savestring (old_trap);
running_trap = sig + 1;
- old_exit_value = last_command_exit_value;
- /* Need to copy the value of line_number because parse_and_execute
- resets it to 1, and the trap command might want it. */
- trap_line_number = line_number;
- parse_and_execute (trap_command, tag, SEVAL_NONINT|SEVAL_NOHIST);
- last_command_exit_value = old_exit_value;
+ trap_saved_exit_value = last_command_exit_value;
+
+ token_state = save_token_state ();
+
+ /* If we're in a function, make sure return longjmps come here, too. */
+ save_return_catch_flag = return_catch_flag;
+ if (return_catch_flag)
+ {
+ COPY_PROCENV (return_catch, save_return_catch);
+ function_code = setjmp (return_catch);
+ }
+
+ if (function_code == 0)
+ parse_and_execute (trap_command, tag, SEVAL_NONINT|SEVAL_NOHIST);
+
+ restore_token_state (token_state);
+ free (token_state);
+
+ trap_exit_value = last_command_exit_value;
+ last_command_exit_value = trap_saved_exit_value;
running_trap = 0;
sigmodes[sig] &= ~SIG_INPROGRESS;
if (sigmodes[sig] & SIG_CHANGED)
{
- free (old_trap);
+#if 0
+ /* Special traps like EXIT, DEBUG, RETURN are handled explicitly in
+ the places where they can be changed using unwind-protects. For
+ example, look at execute_cmd.c:execute_function(). */
+ if (SPECIAL_TRAP (sig) == 0)
+#endif
+ free (old_trap);
sigmodes[sig] &= ~SIG_CHANGED;
}
+
+ if (save_return_catch_flag)
+ {
+ return_catch_flag = save_return_catch_flag;
+ return_catch_value = trap_exit_value;
+ COPY_PROCENV (save_return_catch, return_catch);
+ if (function_code)
+ longjmp (return_catch, 1);
+ }
+ }
+
+ return trap_exit_value;
+}
+
+int
+run_debug_trap ()
+{
+ int trap_exit_value;
+
+ /* XXX - question: should the DEBUG trap inherit the RETURN trap? */
+ trap_exit_value = 0;
+ if ((sigmodes[DEBUG_TRAP] & SIG_TRAPPED) && ((sigmodes[DEBUG_TRAP] & SIG_IGNORED) == 0) && ((sigmodes[DEBUG_TRAP] & SIG_INPROGRESS) == 0))
+ {
+ trap_exit_value = _run_trap_internal (DEBUG_TRAP, "debug trap");
+
+#if defined (DEBUGGER)
+ /* If we're in the debugger and the DEBUG trap returns 2 while we're in
+ a function or sourced script, we force a `return'. */
+ if (debugging_mode && trap_exit_value == 2 && return_catch_flag)
+ {
+ return_catch_value = trap_exit_value;
+ longjmp (return_catch, 1);
+ }
+#endif
}
+ return trap_exit_value;
}
void
-run_debug_trap ()
+run_error_trap ()
+{
+ if ((sigmodes[ERROR_TRAP] & SIG_TRAPPED) && ((sigmodes[ERROR_TRAP] & SIG_IGNORED) == 0) && (sigmodes[ERROR_TRAP] & SIG_INPROGRESS) == 0)
+ _run_trap_internal (ERROR_TRAP, "error trap");
+}
+
+void
+run_return_trap ()
{
- if ((sigmodes[DEBUG_TRAP] & SIG_TRAPPED) && (sigmodes[DEBUG_TRAP] & SIG_INPROGRESS) == 0)
- _run_trap_internal (DEBUG_TRAP, "debug trap");
+ int old_exit_value;
+
+#if 0
+ if ((sigmodes[DEBUG_TRAP] & SIG_TRAPPED) && (sigmodes[DEBUG_TRAP] & SIG_INPROGRESS))
+ return;
+#endif
+
+ if ((sigmodes[RETURN_TRAP] & SIG_TRAPPED) && ((sigmodes[RETURN_TRAP] & SIG_IGNORED) == 0) && (sigmodes[RETURN_TRAP] & SIG_INPROGRESS) == 0)
+ {
+ old_exit_value = last_command_exit_value;
+ _run_trap_internal (RETURN_TRAP, "return trap");
+ last_command_exit_value = old_exit_value;
+ }
}
/* Run a trap set on SIGINT. This is called from throw_to_top_level (), and
{
register int i;
- for (i = 0; i < NSIG+1; i++)
+ for (i = 0; i < BASH_NSIG; i++)
{
free_trap_command (i);
trap_list[i] = (char *)DEFAULT_SIG;
sigmodes[i] &= ~SIG_TRAPPED;
}
- trap_list[DEBUG_TRAP] = trap_list[EXIT_TRAP] = (char *)NULL;
+ trap_list[DEBUG_TRAP] = trap_list[EXIT_TRAP] = trap_list[ERROR_TRAP] = trap_list[RETURN_TRAP] = (char *)NULL;
}
#endif
int sig;
{
set_signal_handler (sig, original_signals[sig]);
+ sigmodes[sig] &= ~SIG_TRAPPED;
}
/* Set the handler signal SIG to the original and free any trap
static void
reset_or_restore_signal_handlers (reset)
- VFunction *reset;
+ sh_resetsig_func_t *reset;
{
register int i;
/* Take care of the exit trap first */
if (sigmodes[EXIT_TRAP] & SIG_TRAPPED)
{
- free_trap_command (EXIT_TRAP);
- trap_list[EXIT_TRAP] = (char *)NULL;
sigmodes[EXIT_TRAP] &= ~SIG_TRAPPED;
+ if (reset != reset_signal)
+ {
+ free_trap_command (EXIT_TRAP);
+ trap_list[EXIT_TRAP] = (char *)NULL;
+ }
}
+
for (i = 1; i < NSIG; i++)
{
if (sigmodes[i] & SIG_TRAPPED)
else if (sigmodes[i] & SIG_SPECIAL)
(*reset) (i);
}
+
+ /* Command substitution and other child processes don't inherit the
+ debug, error, or return traps. If we're in the debugger, and the
+ `functrace' or `errtrace' options have been set, then let command
+ substitutions inherit them. Let command substitution inherit the
+ RETURN trap if we're in the debugger and tracing functions. */
+#if defined (DEBUGGER)
+ if (debugging_mode == 0 || function_trace_mode == 0)
+#endif
+ sigmodes[DEBUG_TRAP] &= ~SIG_TRAPPED;
+#if defined (DEBUGGER)
+ if (debugging_mode == 0 || error_trace_mode == 0)
+#endif
+ sigmodes[ERROR_TRAP] &= ~SIG_TRAPPED;
+#if defined (DEBUGGER)
+ if (debugging_mode == 0 || function_trace_mode == 0)
+#endif
+ sigmodes[RETURN_TRAP] &= ~SIG_TRAPPED;
}
+/* Reset trapped signals to their original values, but don't free the
+ trap strings. Called by the command substitution code. */
void
reset_signal_handlers ()
{
case DEBUG_TRAP:
run_debug_trap ();
break;
+ case ERROR_TRAP:
+ run_error_trap ();
+ break;
default:
trap_handler (sig);
break;
sigmodes[sig] |= SIG_HARD_IGNORE;
original_signals[sig] = SIG_IGN;
}
+
+int
+signal_in_progress (sig)
+ int sig;
+{
+ return (sigmodes[sig] & SIG_INPROGRESS);
+}
projects / platform / upstream / bash.git / blobdiff