X-Git-Url: http://review.tizen.org/git/?p=platform%2Fupstream%2Fbash.git;a=blobdiff_plain;f=trap.c;h=edce31ab9ba90926abe03f88920d5f20ac526a88;hp=ac4d6eb00cd2a2aca03020c82ce80d9eb647f518;hb=HEAD;hpb=d166f048818e10cf3799aa24a174fb22835f1acc
diff --git a/trap.c b/trap.c
index ac4d6eb..edce31a 100644
--- a/trap.c
+++ b/trap.c
@@ -1,40 +1,59 @@
/* 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) 1987-2013 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
- version.
+ 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 3 of the License, or
+ (at your option) any later version.
- Bash 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.
+ Bash 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 Bash; see the file COPYING. If not, write to the Free Software
- Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
+ You should have received a copy of the GNU General Public License
+ along with Bash. If not, see .
+*/
#include "config.h"
-#include
+#if defined (HAVE_UNISTD_H)
+# include
+#endif
#include "bashtypes.h"
-#include "trap.h"
-
#include "bashansi.h"
-#if defined (HAVE_UNISTD_H)
-# include
-#endif
+#include
+#include
+
+#include "bashintl.h"
+
+#include
+
+#include "trap.h"
#include "shell.h"
+#include "flags.h"
+#include "input.h" /* for save_token_state, restore_token_state */
+#include "jobs.h"
#include "signames.h"
+#include "builtins.h"
#include "builtins/common.h"
+#include "builtins/builtext.h"
+
+#if defined (READLINE)
+# include
+# include "bashline.h"
+#endif
+
+#ifndef errno
+extern int errno;
+#endif
/* Flags which describe the current handling state of a signal. */
#define SIG_INHERITED 0x0 /* Value inherited from parent. */
@@ -46,28 +65,46 @@
#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 int _run_trap_internal __P((int, char *));
-static void change_signal (), restore_signal ();
+static void free_trap_string __P((int));
+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 int sigalrm_seen;
+extern procenv_t alrmbuf;
+
+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;
+extern WORD_LIST *subst_assign_varlist;
+
/* The list of things to do originally, before we started trapping. */
SigHandler *original_signals[NSIG];
/* For each signal, a slot for a string, which is a command to be
- executed when that signal is recieved. The slot can also contain
+ executed when that signal is received. The slot can also contain
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];
@@ -78,64 +115,109 @@ 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;
-/* A value which can never be the target of a trap handler. */
-#define IMPOSSIBLE_TRAP_HANDLER (SigHandler *)initialize_traps
+/* The (trapped) signal received while executing in the `wait' builtin */
+int wait_signal_received;
+
+int trapped_signal_received;
+
+#define GETORIGSIG(sig) \
+ do { \
+ original_signals[sig] = (SigHandler *)set_signal_handler (sig, SIG_DFL); \
+ set_signal_handler (sig, original_signals[sig]); \
+ if (original_signals[sig] == SIG_IGN) \
+ sigmodes[sig] |= SIG_HARD_IGNORE; \
+ } while (0)
+
+#define SETORIGSIG(sig,handler) \
+ do { \
+ original_signals[sig] = handler; \
+ if (original_signals[sig] == SIG_IGN) \
+ sigmodes[sig] |= SIG_HARD_IGNORE; \
+ } while (0)
+
+#define GET_ORIGINAL_SIGNAL(sig) \
+ if (sig && sig < NSIG && original_signals[sig] == IMPOSSIBLE_TRAP_HANDLER) \
+ GETORIGSIG(sig)
void
initialize_traps ()
{
register int i;
- trap_list[EXIT_TRAP] = trap_list[DEBUG_TRAP] = (char *)NULL;
- sigmodes[EXIT_TRAP] = sigmodes[DEBUG_TRAP] = SIG_INHERITED;
+ initialize_signames();
+
+ 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++)
{
pending_traps[i] = 0;
trap_list[i] = (char *)DEFAULT_SIG;
- sigmodes[i] = SIG_INHERITED;
+ sigmodes[i] = SIG_INHERITED; /* XXX - only set, not used */
original_signals[i] = IMPOSSIBLE_TRAP_HANDLER;
}
/* Show which signals are treated specially by the shell. */
#if defined (SIGCHLD)
- original_signals[SIGCHLD] =
- (SigHandler *) set_signal_handler (SIGCHLD, SIG_DFL);
- set_signal_handler (SIGCHLD, original_signals[SIGCHLD]);
+ GETORIGSIG (SIGCHLD);
sigmodes[SIGCHLD] |= (SIG_SPECIAL | SIG_NO_TRAP);
#endif /* SIGCHLD */
- original_signals[SIGINT] =
- (SigHandler *) set_signal_handler (SIGINT, SIG_DFL);
- set_signal_handler (SIGINT, original_signals[SIGINT]);
+ GETORIGSIG (SIGINT);
sigmodes[SIGINT] |= SIG_SPECIAL;
- original_signals[SIGQUIT] =
- (SigHandler *) set_signal_handler (SIGQUIT, SIG_DFL);
- set_signal_handler (SIGQUIT, original_signals[SIGQUIT]);
+#if defined (__BEOS__)
+ /* BeOS sets SIGINT to SIG_IGN! */
+ original_signals[SIGINT] = SIG_DFL;
+ sigmodes[SIGINT] &= ~SIG_HARD_IGNORE;
+#endif
+
+ GETORIGSIG (SIGQUIT);
sigmodes[SIGQUIT] |= SIG_SPECIAL;
if (interactive)
{
- original_signals[SIGTERM] =
- (SigHandler *)set_signal_handler (SIGTERM, SIG_DFL);
- set_signal_handler (SIGTERM, original_signals[SIGTERM]);
+ GETORIGSIG (SIGTERM);
sigmodes[SIGTERM] |= SIG_SPECIAL;
}
}
+#ifdef DEBUG
+/* 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 >= BASH_NSIG || sig < 0 || signal_names[sig] == NULL)
+ ? _("invalid signal number")
+ : signal_names[sig];
+
+ return ret;
}
/* Turn a string into a signal number, or a number into
@@ -143,18 +225,47 @@ signal_name (sig)
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);
- for (sig = 0; sig <= NSIG; sig++)
- if (strcasecmp (string, signal_names[sig]) == 0 ||
- strcasecmp (string, &(signal_names[sig])[3]) == 0)
- return ((int)sig);
+ /* A leading `SIG' may be omitted. */
+ 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 sensitively 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);
}
@@ -167,55 +278,133 @@ run_pending_traps ()
{
register int sig;
int old_exit_value;
+ WORD_LIST *save_subst_varlist;
+ sh_parser_state_t pstate;
+#if defined (ARRAY_VARS)
+ ARRAY *ps;
+#endif
if (catch_flag == 0) /* simple optimization */
return;
- catch_flag = 0;
+ if (running_trap > 0)
+ {
+#if defined (DEBUG)
+ internal_warning ("run_pending_traps: recursive invocation while running trap for signal %d", running_trap-1);
+#endif
+#if 0
+ return; /* no recursive trap invocations */
+#else
+ ;
+#endif
+ }
+
+ catch_flag = trapped_signal_received = 0;
/* Preserve $? when running trap. */
old_exit_value = last_command_exit_value;
+#if defined (ARRAY_VARS)
+ ps = save_pipestatus_array ();
+#endif
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)
- sigset_t set, oset;
-
- sigemptyset (&set);
- sigemptyset (&oset);
+ if (running_trap == sig+1)
+ /*continue*/;
- sigaddset (&set, sig);
- sigprocmask (SIG_BLOCK, &set, &oset);
-#else
-# if defined (HAVE_BSD_SIGNALS)
- int oldmask = sigblock (sigmask (sig));
-# endif
-#endif /* HAVE_POSIX_SIGNALS */
+ running_trap = sig + 1;
if (sig == SIGINT)
{
+ pending_traps[sig] = 0; /* XXX */
run_interrupt_trap ();
CLRINTERRUPT;
}
+#if defined (JOB_CONTROL) && defined (SIGCHLD)
+ else if (sig == SIGCHLD &&
+ trap_list[SIGCHLD] != (char *)IMPOSSIBLE_TRAP_HANDLER &&
+ (sigmodes[SIGCHLD] & SIG_INPROGRESS) == 0)
+ {
+ sigmodes[SIGCHLD] |= SIG_INPROGRESS;
+ run_sigchld_trap (pending_traps[sig]); /* use as counter */
+ sigmodes[SIGCHLD] &= ~SIG_INPROGRESS;
+ }
+ else if (sig == SIGCHLD &&
+ trap_list[SIGCHLD] == (char *)IMPOSSIBLE_TRAP_HANDLER &&
+ (sigmodes[SIGCHLD] & SIG_INPROGRESS) != 0)
+ {
+ /* This can happen when run_pending_traps is called while
+ running a SIGCHLD trap handler. */
+ running_trap = 0;
+ /* want to leave pending_traps[SIGCHLD] alone here */
+ continue; /* XXX */
+ }
+ else if (sig == SIGCHLD && (sigmodes[SIGCHLD] & SIG_INPROGRESS))
+ {
+ /* whoops -- print warning? */
+ running_trap = 0; /* XXX */
+ /* want to leave pending_traps[SIGCHLD] alone here */
+ continue;
+ }
+#endif
+ 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);
+ {
+ /* XXX - should we use save_parser_state/restore_parser_state? */
+ save_parser_state (&pstate);
+ save_subst_varlist = subst_assign_varlist;
+ subst_assign_varlist = 0;
- pending_traps[sig] = 0;
+#if defined (JOB_CONTROL)
+ save_pipeline (1); /* XXX only provides one save level */
+#endif
+ /* XXX - set pending_traps[sig] = 0 here? */
+ pending_traps[sig] = 0;
+ evalstring (savestring (trap_list[sig]), "trap", SEVAL_NONINT|SEVAL_NOHIST|SEVAL_RESETLINE);
+#if defined (JOB_CONTROL)
+ restore_pipeline (1);
+#endif
-#if defined (HAVE_POSIX_SIGNALS)
- sigprocmask (SIG_SETMASK, &oset, (sigset_t *)NULL);
-#else
-# if defined (HAVE_BSD_SIGNALS)
- sigsetmask (oldmask);
-# endif
-#endif /* POSIX_VERSION */
+ subst_assign_varlist = save_subst_varlist;
+ restore_parser_state (&pstate);
+ }
+
+ pending_traps[sig] = 0; /* XXX - move before evalstring? */
+ running_trap = 0;
}
}
+#if defined (ARRAY_VARS)
+ restore_pipestatus_array (ps);
+#endif
last_command_exit_value = old_exit_value;
}
@@ -223,27 +412,100 @@ sighandler
trap_handler (sig)
int sig;
{
+ int oerrno;
+
+ if ((sigmodes[sig] & SIG_TRAPPED) == 0)
+ {
+#if defined (DEBUG)
+ internal_warning ("trap_handler: signal %d: signal not trapped", sig);
+#endif
+ SIGRETURN (0);
+ }
+
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)
+# if defined (JOB_CONTROL) && defined (SIGCHLD)
+ if (sig != SIGCHLD)
+# endif /* JOB_CONTROL && SIGCHLD */
set_signal_handler (sig, trap_handler);
#endif /* MUST_REINSTALL_SIGHANDLERS */
catch_flag = 1;
pending_traps[sig]++;
+ trapped_signal_received = sig;
+
+ if (this_shell_builtin && (this_shell_builtin == wait_builtin))
+ {
+ wait_signal_received = sig;
+ if (interrupt_immediately)
+ longjmp (wait_intr_buf, 1);
+ }
+
+#if defined (READLINE)
+ /* Set the event hook so readline will call it after the signal handlers
+ finish executing, so if this interrupted character input we can get
+ quick response. */
+ if (RL_ISSTATE (RL_STATE_SIGHANDLER) && interrupt_immediately == 0)
+ bashline_set_event_hook ();
+#endif
+
if (interrupt_immediately)
run_pending_traps ();
+
+ errno = oerrno;
}
SIGRETURN (0);
}
+int
+first_pending_trap ()
+{
+ register int i;
+
+ for (i = 1; i < NSIG; i++)
+ if (pending_traps[i])
+ return i;
+ return -1;
+}
+
+int
+any_signals_trapped ()
+{
+ register int i;
+
+ for (i = 1; i < NSIG; i++)
+ if (sigmodes[i] & SIG_TRAPPED)
+ return i;
+ return -1;
+}
+
+void
+check_signals ()
+{
+ CHECK_ALRM; /* set by the read builtin */
+ QUIT;
+}
+
+/* Convenience functions the rest of the shell can use */
+void
+check_signals_and_traps ()
+{
+ check_signals ();
+
+ run_pending_traps ();
+}
+
#if defined (JOB_CONTROL) && defined (SIGCHLD)
+
+#ifdef INCLUDE_UNUSED
/* Make COMMAND_STRING be executed when SIGCHLD is caught. */
void
set_sigchld_trap (command_string)
@@ -251,16 +513,46 @@ 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. */
+/* Make COMMAND_STRING be executed when SIGCHLD is caught iff SIGCHLD
+ is not already trapped. IMPOSSIBLE_TRAP_HANDLER is used as a sentinel
+ to make sure that a SIGCHLD trap handler run via run_sigchld_trap can
+ reset the disposition to the default and not have the original signal
+ accidentally restored, undoing the user's command. */
void
maybe_set_sigchld_trap (command_string)
char *command_string;
{
- if ((sigmodes[SIGCHLD] & SIG_TRAPPED) == 0)
+ if ((sigmodes[SIGCHLD] & SIG_TRAPPED) == 0 && trap_list[SIGCHLD] == (char *)IMPOSSIBLE_TRAP_HANDLER)
set_signal (SIGCHLD, command_string);
}
+
+/* Temporarily set the SIGCHLD trap string to IMPOSSIBLE_TRAP_HANDLER. Used
+ as a sentinel in run_sigchld_trap and maybe_set_sigchld_trap to see whether
+ or not a SIGCHLD trap handler reset SIGCHLD disposition to the default. */
+void
+set_impossible_sigchld_trap ()
+{
+ restore_default_signal (SIGCHLD);
+ change_signal (SIGCHLD, (char *)IMPOSSIBLE_TRAP_HANDLER);
+ sigmodes[SIGCHLD] &= ~SIG_TRAPPED; /* maybe_set_sigchld_trap checks this */
+}
+
+/* Act as if we received SIGCHLD NCHILD times and increment
+ pending_traps[SIGCHLD] by that amount. This allows us to still run the
+ SIGCHLD trap once for each exited child. */
+void
+queue_sigchld_trap (nchild)
+ int nchild;
+{
+ if (nchild > 0)
+ {
+ catch_flag = 1;
+ pending_traps[SIGCHLD] += nchild;
+ trapped_signal_received = SIGCHLD;
+ }
+}
#endif /* JOB_CONTROL && SIGCHLD */
void
@@ -271,11 +563,27 @@ set_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)
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
@@ -297,7 +605,21 @@ set_sigint_handler ()
else if (interactive) /* XXX - was interactive_shell */
return (set_signal_handler (SIGINT, sigint_sighandler));
else
- return (set_signal_handler (SIGINT, termination_unwind_protect));
+ return (set_signal_handler (SIGINT, termsig_sighandler));
+}
+
+/* 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. */
@@ -306,7 +628,9 @@ set_signal (sig, string)
int sig;
char *string;
{
- if (sig == DEBUG_TRAP || sig == EXIT_TRAP)
+ sigset_t set, oset;
+
+ if (SPECIAL_TRAP (sig))
{
change_signal (sig, savestring (string));
if (sig == EXIT_TRAP && interactive == 0)
@@ -325,17 +649,9 @@ set_signal (sig, string)
{
/* If we aren't sure of the original value, check it. */
if (original_signals[sig] == IMPOSSIBLE_TRAP_HANDLER)
- {
- original_signals[sig] = (SigHandler *)set_signal_handler (sig, SIG_DFL);
- set_signal_handler (sig, original_signals[sig]);
- }
-
- /* Signals ignored on entry to the shell cannot be trapped or reset. */
+ GETORIGSIG (sig);
if (original_signals[sig] == SIG_IGN)
- {
- sigmodes[sig] |= SIG_HARD_IGNORE;
- return;
- }
+ return;
}
/* Only change the system signal handler if SIG_NO_TRAP is not set.
@@ -344,9 +660,10 @@ set_signal (sig, string)
environment in which it is safe to do so. */
if ((sigmodes[sig] & SIG_NO_TRAP) == 0)
{
- set_signal_handler (sig, SIG_IGN);
+ BLOCK_SIGNAL (sig, set, oset);
change_signal (sig, savestring (string));
set_signal_handler (sig, trap_handler);
+ UNBLOCK_SIGNAL (oset);
}
else
change_signal (sig, savestring (string));
@@ -383,25 +700,31 @@ change_signal (sig, value)
sigmodes[sig] |= SIG_CHANGED;
}
-#define GET_ORIGINAL_SIGNAL(sig) \
- if (sig && sig < NSIG && original_signals[sig] == IMPOSSIBLE_TRAP_HANDLER) \
- get_original_signal (sig)
-
-static void
+void
get_original_signal (sig)
int sig;
{
/* If we aren't sure the of the original value, then get it. */
- if (original_signals[sig] == (SigHandler *)IMPOSSIBLE_TRAP_HANDLER)
- {
- original_signals[sig] =
- (SigHandler *) set_signal_handler (sig, SIG_DFL);
- set_signal_handler (sig, original_signals[sig]);
+ if (sig > 0 && sig < NSIG && original_signals[sig] == (SigHandler *)IMPOSSIBLE_TRAP_HANDLER)
+ GETORIGSIG (sig);
+}
- /* Signals ignored on entry to the shell cannot be trapped. */
- if (original_signals[sig] == SIG_IGN)
- sigmodes[sig] |= SIG_HARD_IGNORE;
- }
+void
+get_all_original_signals ()
+{
+ register int i;
+
+ for (i = 1; i < NSIG; i++)
+ GET_ORIGINAL_SIGNAL (i);
+}
+
+void
+set_original_signal (sig, handler)
+ int sig;
+ SigHandler *handler;
+{
+ if (sig > 0 && sig < NSIG && original_signals[sig] == (SigHandler *)IMPOSSIBLE_TRAP_HANDLER)
+ SETORIGSIG (sig, handler);
}
/* Restore the default action for SIG; i.e., the action the shell
@@ -412,9 +735,10 @@ void
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;
@@ -431,7 +755,11 @@ restore_default_signal (sig)
return;
/* If we aren't trapping this signal, don't bother doing anything else. */
- if ((sigmodes[sig] & SIG_TRAPPED) == 0)
+ /* We special-case SIGCHLD and IMPOSSIBLE_TRAP_HANDLER (see above) as a
+ sentinel to determine whether or not disposition is reset to the default
+ while the trap handler is executing. */
+ if (((sigmodes[sig] & SIG_TRAPPED) == 0) &&
+ (sig != SIGCHLD || (sigmodes[sig] & SIG_INPROGRESS) == 0 || trap_list[sig] != (char *)IMPOSSIBLE_TRAP_HANDLER))
return;
/* Only change the signal handler for SIG if it allows it. */
@@ -450,7 +778,7 @@ void
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;
@@ -482,9 +810,16 @@ int
run_exit_trap ()
{
char *trap_command;
- int code, old_exit_value;
+ int code, function_code, retval;
+#if defined (ARRAY_VARS)
+ ARRAY *ps;
+#endif
- old_exit_value = last_command_exit_value;
+ trap_saved_exit_value = last_command_exit_value;
+#if defined (ARRAY_VARS)
+ ps = save_pipestatus_array ();
+#endif
+ 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
@@ -496,17 +831,37 @@ run_exit_trap ()
sigmodes[EXIT_TRAP] &= ~SIG_TRAPPED;
sigmodes[EXIT_TRAP] |= SIG_INPROGRESS;
- code = setjmp (top_level);
+ retval = trap_saved_exit_value;
+ running_trap = 1;
+
+ code = setjmp_nosigs (top_level);
+
+ /* If we're in a function, make sure return longjmps come here, too. */
+ if (return_catch_flag)
+ function_code = setjmp_nosigs (return_catch);
- if (code == 0)
- parse_and_execute (trap_command, "exit trap", SEVAL_NONINT|SEVAL_NOHIST);
+ if (code == 0 && function_code == 0)
+ {
+ reset_parser ();
+ parse_and_execute (trap_command, "exit trap", SEVAL_NONINT|SEVAL_NOHIST|SEVAL_RESETLINE);
+ }
+ 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);
+#if defined (ARRAY_VARS)
+ restore_pipestatus_array (ps);
+#endif
+ return (trap_saved_exit_value);
}
void
@@ -516,21 +871,38 @@ run_trap_cleanup (sig)
sigmodes[sig] &= ~(SIG_INPROGRESS|SIG_CHANGED);
}
+#define RECURSIVE_SIG(s) (SPECIAL_TRAP(s) == 0)
+
/* 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;
+ volatile int save_return_catch_flag, function_code;
+ int flags;
+ procenv_t save_return_catch;
+ WORD_LIST *save_subst_varlist;
+ sh_parser_state_t pstate;
+#if defined (ARRAY_VARS)
+ ARRAY *ps;
+#endif
+ 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_list[sig] != (char *)IMPOSSIBLE_TRAP_HANDLER) &&
+#if 0
+ /* Uncomment this to allow some special signals to recursively execute
+ trap handlers. */
+ (RECURSIVE_SIG (sig) || (sigmodes[sig] & SIG_INPROGRESS) == 0))
+#else
((sigmodes[sig] & SIG_INPROGRESS) == 0))
+#endif
{
old_trap = trap_list[sig];
sigmodes[sig] |= SIG_INPROGRESS;
@@ -538,29 +910,147 @@ _run_trap_internal (sig, tag)
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;
+
+#if defined (ARRAY_VARS)
+ ps = save_pipestatus_array ();
+#endif
+
+ save_parser_state (&pstate);
+ save_subst_varlist = subst_assign_varlist;
+ subst_assign_varlist = 0;
+
+#if defined (JOB_CONTROL)
+ if (sig != DEBUG_TRAP) /* run_debug_trap does this */
+ save_pipeline (1); /* XXX only provides one save level */
+#endif
+
+ /* 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_nosigs (return_catch);
+ }
+
+ flags = SEVAL_NONINT|SEVAL_NOHIST;
+ if (sig != DEBUG_TRAP && sig != RETURN_TRAP && sig != ERROR_TRAP)
+ flags |= SEVAL_RESETLINE;
+ if (function_code == 0)
+ parse_and_execute (trap_command, tag, flags);
+
+ trap_exit_value = last_command_exit_value;
+
+#if defined (JOB_CONTROL)
+ if (sig != DEBUG_TRAP) /* run_debug_trap does this */
+ restore_pipeline (1);
+#endif
+
+ subst_assign_varlist = save_subst_varlist;
+ restore_parser_state (&pstate);
+
+#if defined (ARRAY_VARS)
+ restore_pipestatus_array (ps);
+#endif
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;
}
-void
+int
run_debug_trap ()
{
- if ((sigmodes[DEBUG_TRAP] & SIG_TRAPPED) && (sigmodes[DEBUG_TRAP] & SIG_INPROGRESS) == 0)
- _run_trap_internal (DEBUG_TRAP, "debug trap");
+ int trap_exit_value;
+ pid_t save_pgrp;
+ int save_pipe[2];
+
+ /* 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))
+ {
+#if defined (JOB_CONTROL)
+ save_pgrp = pipeline_pgrp;
+ pipeline_pgrp = 0;
+ save_pipeline (1);
+# if defined (PGRP_PIPE)
+ save_pgrp_pipe (save_pipe, 1);
+# endif
+ stop_making_children ();
+#endif
+
+ trap_exit_value = _run_trap_internal (DEBUG_TRAP, "debug trap");
+
+#if defined (JOB_CONTROL)
+ pipeline_pgrp = save_pgrp;
+ restore_pipeline (1);
+# if defined (PGRP_PIPE)
+ close_pgrp_pipe ();
+ restore_pgrp_pipe (save_pipe);
+# endif
+ if (pipeline_pgrp > 0)
+ give_terminal_to (pipeline_pgrp, 1);
+ notify_and_cleanup ();
+#endif
+
+#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_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 ()
+{
+ 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
@@ -572,27 +1062,43 @@ run_interrupt_trap ()
}
/* Free all the allocated strings in the list of traps and reset the trap
- values to the default. */
+ values to the default. Intended to be called from subshells that want
+ to complete work done by reset_signal_handlers upon execution of a
+ subsequent `trap' command that changes a signal's disposition. We need
+ to make sure that we duplicate the behavior of
+ reset_or_restore_signal_handlers and not change the disposition of signals
+ that are set to be ignored. */
void
free_trap_strings ()
{
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;
+ if (trap_list[i] != (char *)IGNORE_SIG)
+ free_trap_string (i);
}
- 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;
+}
+
+/* Free a trap command string associated with SIG without changing signal
+ disposition. Intended to be called from free_trap_strings() */
+static void
+free_trap_string (sig)
+ int sig;
+{
+ change_signal (sig, (char *)DEFAULT_SIG);
+ sigmodes[sig] &= ~SIG_TRAPPED;
}
-/* Reset the handler for SIG to the original value. */
+/* Reset the handler for SIG to the original value but leave the trap string
+ in place. */
static void
reset_signal (sig)
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
@@ -608,17 +1114,21 @@ restore_signal (sig)
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)
@@ -631,8 +1141,24 @@ reset_or_restore_signal_handlers (reset)
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 (function_trace_mode == 0)
+ {
+ sigmodes[DEBUG_TRAP] &= ~SIG_TRAPPED;
+ sigmodes[RETURN_TRAP] &= ~SIG_TRAPPED;
+ }
+ if (error_trace_mode == 0)
+ sigmodes[ERROR_TRAP] &= ~SIG_TRAPPED;
}
+/* Reset trapped signals to their original values, but don't free the
+ trap strings. Called by the command substitution code and other places
+ that create a "subshell environment". */
void
reset_signal_handlers ()
{
@@ -649,7 +1175,7 @@ restore_original_signals ()
}
/* If a trap handler exists for signal SIG, then call it; otherwise just
- return failure. */
+ return failure. Returns 1 if it called the trap handler. */
int
maybe_call_trap_handler (sig)
int sig;
@@ -668,6 +1194,9 @@ maybe_call_trap_handler (sig)
case DEBUG_TRAP:
run_debug_trap ();
break;
+ case ERROR_TRAP:
+ run_error_trap ();
+ break;
default:
trap_handler (sig);
break;
@@ -686,6 +1215,13 @@ signal_is_trapped (sig)
}
int
+signal_is_pending (sig)
+ int sig;
+{
+ return (pending_traps[sig]);
+}
+
+int
signal_is_special (sig)
int sig;
{
@@ -699,10 +1235,31 @@ signal_is_ignored (sig)
return (sigmodes[sig] & SIG_IGNORED);
}
+int
+signal_is_hard_ignored (sig)
+ int sig;
+{
+ return (sigmodes[sig] & SIG_HARD_IGNORE);
+}
+
void
-set_signal_ignored (sig)
+set_signal_hard_ignored (sig)
int sig;
{
sigmodes[sig] |= SIG_HARD_IGNORE;
original_signals[sig] = SIG_IGN;
}
+
+void
+set_signal_ignored (sig)
+ int sig;
+{
+ original_signals[sig] = SIG_IGN;
+}
+
+int
+signal_in_progress (sig)
+ int sig;
+{
+ return (sigmodes[sig] & SIG_INPROGRESS);
+}