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 <stdio.h>
+#if defined (HAVE_UNISTD_H)
+# include <unistd.h>
+#endif
#include "bashtypes.h"
-#include "trap.h"
+#include "bashansi.h"
-#if defined (HAVE_STRING_H)
-# include <string.h>
-#else /* !HAVE_STRING_H */
-# include <strings.h>
-#endif /* !HAVE_STRING_H */
+#include <stdio.h>
+#include <errno.h>
-#if defined (HAVE_UNISTD_H)
-# include <unistd.h>
-#endif
+#include "trap.h"
#include "shell.h"
+#include "input.h" /* for save_token_state, restore_token_state */
#include "signames.h"
#include "builtins/common.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_TRAPPED 0x1 /* Currently trapped. */
extern int interactive_shell, interactive;
extern int interrupt_immediately;
extern int last_command_exit_value;
+extern int line_number;
/* The list of things to do originally, before we started trapping. */
SigHandler *original_signals[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;
+
/* A value which can never be the target of a trap handler. */
#define IMPOSSIBLE_TRAP_HANDLER (SigHandler *)initialize_traps
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)
int sig;
{
- return ((sig > NSIG || sig < 0) ? "bad signal number" : signal_names[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";
+ return ret;
}
/* Turn a string into a signal number, or a number into
if (legal_number (string, &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 ||
- strcasecmp (string, &(signal_names[sig])[3]) == 0)
- return ((int)sig);
+ {
+ if (signal_names[sig] == 0 || signal_names[sig][0] == '\0')
+ continue;
+ if (strcasecmp (string, signal_names[sig]) == 0 ||
+ (STREQN (signal_names[sig], "SIG", 3) &&
+ strcasecmp (string, &(signal_names[sig])[3]) == 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]: 0x%x",
+ sig, (int)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", 0);
+ {
+ 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);
else
{
+ oerrno = errno;
#if defined (MUST_REINSTALL_SIGHANDLERS)
set_signal_handler (sig, trap_handler);
#endif /* MUST_REINSTALL_SIGHANDLERS */
if (interrupt_immediately)
run_pending_traps ();
+
+ errno = oerrno;
}
SIGRETURN (0);
}
#if defined (JOB_CONTROL) && defined (SIGCHLD)
+
+#ifdef INCLUDE_UNUSED
/* Make COMMAND_STRING be executed when SIGCHLD is caught. */
void
set_sigchld_trap (command_string)
{
set_signal (SIGCHLD, command_string);
}
+#endif
/* Make COMMAND_STRING be executed when SIGCHLD is caught iff the current
SIGCHLD trap handler is DEFAULT_SIG. */
set_signal (DEBUG_TRAP, command);
}
+#ifdef INCLUDE_UNUSED
void
set_sigint_trap (command)
char *command;
{
set_signal (SIGINT, command);
}
+#endif
/* Reset the SIGINT handler so that subshells that are doing `shellsy'
things, like waiting for command substitution or executing commands
return (set_signal_handler (SIGINT, termination_unwind_protect));
}
+/* Return the correct handler for signal SIG according to the values in
+ sigmodes[SIG]. */
+SigHandler *
+trap_to_sighandler (sig)
+ int sig;
+{
+ if (sigmodes[sig] & (SIG_IGNORED|SIG_HARD_IGNORE))
+ return (SIG_IGN);
+ else if (sigmodes[sig] & SIG_TRAPPED)
+ return (trap_handler);
+ else
+ return (SIG_DFL);
+}
+
/* Set SIG to call STRING as a command. */
void
set_signal (sig, string)
if (sig == DEBUG_TRAP || sig == EXIT_TRAP)
{
change_signal (sig, savestring (string));
+ if (sig == EXIT_TRAP && interactive == 0)
+ initialize_terminating_signals ();
return;
}
int sig;
char *value;
{
- free_trap_command (sig);
+ if ((sigmodes[sig] & SIG_INPROGRESS) == 0)
+ free_trap_command (sig);
trap_list[sig] = value;
sigmodes[sig] |= SIG_TRAPPED;
{
if (sig == DEBUG_TRAP || sig == EXIT_TRAP)
{
- free_trap_command (sig);
+ if ((sig != DEBUG_TRAP) || (sigmodes[sig] & SIG_INPROGRESS) == 0)
+ free_trap_command (sig);
trap_list[sig] = (char *)NULL;
sigmodes[sig] &= ~SIG_TRAPPED;
+ if (sigmodes[sig] & SIG_INPROGRESS)
+ sigmodes[sig] |= SIG_CHANGED;
return;
}
code = setjmp (top_level);
if (code == 0)
- parse_and_execute (trap_command, "exit trap", 0);
+ {
+ reset_parser ();
+ parse_and_execute (trap_command, "exit trap", SEVAL_NONINT|SEVAL_NOHIST);
+ }
else if (code == EXITPROG)
- return (last_command_exit_value);
+ return (last_command_exit_value);
else
return (old_exit_value);
}
char *tag;
{
char *trap_command, *old_trap;
- int old_exit_value;
+ int old_exit_value, old_line_number, *token_state;
/* Run the trap only if SIG is trapped and not ignored, and we are not
currently executing in the trap handler. */
running_trap = sig + 1;
old_exit_value = last_command_exit_value;
- parse_and_execute (trap_command, tag, 0);
+ /* 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;
+
+ token_state = save_token_state ();
+ parse_and_execute (trap_command, tag, SEVAL_NONINT|SEVAL_NOHIST);
+ restore_token_state (token_state);
+ free (token_state);
+
last_command_exit_value = old_exit_value;
running_trap = 0;
_run_trap_internal (SIGINT, "interrupt trap");
}
+#ifdef INCLUDE_UNUSED
/* Free all the allocated strings in the list of traps and reset the trap
values to the default. */
void
}
trap_list[DEBUG_TRAP] = trap_list[EXIT_TRAP] = (char *)NULL;
}
+#endif
/* Reset the handler for SIG to the original value. */
static void