Con Kolivas 14 years ago
parent
commit
78b96f9c74
  1. 4
      compat.h
  2. 0
      lib/.gitignore
  3. 56
      lib/Makefile.am
  4. 44
      lib/sig-handler.h
  5. 204
      lib/sigaction.c
  6. 376
      lib/signal.in.h
  7. 329
      lib/sigprocmask.c
  8. 0
      m4/.gitignore
  9. 5
      m4/gnulib-cache.m4
  10. 24
      m4/gnulib-comp.m4
  11. 43
      m4/sigaction.m4
  12. 58
      m4/signal_h.m4
  13. 40
      m4/signalblocking.m4

4
compat.h

@ -1,6 +1,10 @@
#ifndef __COMPAT_H__ #ifndef __COMPAT_H__
#define __COMPAT_H__ #define __COMPAT_H__
#ifndef __SUSECONDS_T_TYPE
typedef long suseconds_t;
#endif
#ifdef WIN32 #ifdef WIN32
#include <windows.h> #include <windows.h>

0
lib/.gitignore vendored

56
lib/Makefile.am

@ -9,7 +9,7 @@
# the same distribution terms as the rest of that program. # the same distribution terms as the rest of that program.
# #
# Generated by gnulib-tool. # Generated by gnulib-tool.
# Reproduce by: gnulib-tool --import --dir=. --lib=libgnu --source-base=lib --m4-base=m4 --doc-base=doc --tests-base=tests --aux-dir=. --no-conditional-dependencies --no-libtool --macro-prefix=gl memmem # Reproduce by: gnulib-tool --import --dir=. --lib=libgnu --source-base=lib --m4-base=m4 --doc-base=doc --tests-base=tests --aux-dir=. --no-conditional-dependencies --no-libtool --macro-prefix=gl --no-vc-files memmem sigaction signal
AUTOMAKE_OPTIONS = 1.5 gnits AUTOMAKE_OPTIONS = 1.5 gnits
@ -102,6 +102,60 @@ EXTRA_libgnu_a_SOURCES += memmem.c
## end gnulib module memmem-simple ## end gnulib module memmem-simple
## begin gnulib module sigaction
EXTRA_DIST += sig-handler.h sigaction.c
EXTRA_libgnu_a_SOURCES += sigaction.c
## end gnulib module sigaction
## begin gnulib module signal
BUILT_SOURCES += signal.h
# We need the following in order to create <signal.h> when the system
# doesn't have a complete one.
signal.h: signal.in.h $(top_builddir)/config.status $(CXXDEFS_H) $(ARG_NONNULL_H) $(WARN_ON_USE_H)
$(AM_V_GEN)rm -f $@-t $@ && \
{ echo '/* DO NOT EDIT! GENERATED AUTOMATICALLY! */' && \
sed -e 's|@''GUARD_PREFIX''@|GL|g' \
-e 's|@''INCLUDE_NEXT''@|$(INCLUDE_NEXT)|g' \
-e 's|@''PRAGMA_SYSTEM_HEADER''@|@PRAGMA_SYSTEM_HEADER@|g' \
-e 's|@''PRAGMA_COLUMNS''@|@PRAGMA_COLUMNS@|g' \
-e 's|@''NEXT_SIGNAL_H''@|$(NEXT_SIGNAL_H)|g' \
-e 's/@''GNULIB_SIGNAL_H_SIGPIPE''@/$(GNULIB_SIGNAL_H_SIGPIPE)/g' \
-e 's/@''GNULIB_SIGPROCMASK''@/$(GNULIB_SIGPROCMASK)/g' \
-e 's/@''GNULIB_SIGACTION''@/$(GNULIB_SIGACTION)/g' \
-e 's|@''HAVE_POSIX_SIGNALBLOCKING''@|$(HAVE_POSIX_SIGNALBLOCKING)|g' \
-e 's|@''HAVE_SIGSET_T''@|$(HAVE_SIGSET_T)|g' \
-e 's|@''HAVE_SIGINFO_T''@|$(HAVE_SIGINFO_T)|g' \
-e 's|@''HAVE_SIGACTION''@|$(HAVE_SIGACTION)|g' \
-e 's|@''HAVE_STRUCT_SIGACTION_SA_SIGACTION''@|$(HAVE_STRUCT_SIGACTION_SA_SIGACTION)|g' \
-e 's|@''HAVE_TYPE_VOLATILE_SIG_ATOMIC_T''@|$(HAVE_TYPE_VOLATILE_SIG_ATOMIC_T)|g' \
-e 's|@''HAVE_SIGHANDLER_T''@|$(HAVE_SIGHANDLER_T)|g' \
-e '/definitions of _GL_FUNCDECL_RPL/r $(CXXDEFS_H)' \
-e '/definition of _GL_ARG_NONNULL/r $(ARG_NONNULL_H)' \
-e '/definition of _GL_WARN_ON_USE/r $(WARN_ON_USE_H)' \
< $(srcdir)/signal.in.h; \
} > $@-t && \
mv $@-t $@
MOSTLYCLEANFILES += signal.h signal.h-t
EXTRA_DIST += signal.in.h
## end gnulib module signal
## begin gnulib module sigprocmask
EXTRA_DIST += sigprocmask.c
EXTRA_libgnu_a_SOURCES += sigprocmask.c
## end gnulib module sigprocmask
## begin gnulib module stddef ## begin gnulib module stddef
BUILT_SOURCES += $(STDDEF_H) BUILT_SOURCES += $(STDDEF_H)

44
lib/sig-handler.h

@ -0,0 +1,44 @@
/* Convenience declarations when working with <signal.h>.
Copyright (C) 2008-2011 Free Software Foundation, Inc.
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 3 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.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
#ifndef _GL_SIG_HANDLER_H
#define _GL_SIG_HANDLER_H
#include <signal.h>
/* Convenience type when working with signal handlers. */
typedef void (*sa_handler_t) (int);
/* Return the handler of a signal, as a sa_handler_t value regardless
of its true type. The resulting function can be compared to
special values like SIG_IGN but it is not portable to call it. */
static inline sa_handler_t
get_handler (struct sigaction const *a)
{
#ifdef SA_SIGINFO
/* POSIX says that special values like SIG_IGN can only occur when
action.sa_flags does not contain SA_SIGINFO. But in Linux 2.4,
for example, sa_sigaction and sa_handler are aliases and a signal
is ignored if sa_sigaction (after casting) equals SIG_IGN. So
use (and cast) sa_sigaction in that case. */
if (a->sa_flags & SA_SIGINFO)
return (sa_handler_t) a->sa_sigaction;
#endif
return a->sa_handler;
}
#endif /* _GL_SIG_HANDLER_H */

204
lib/sigaction.c

@ -0,0 +1,204 @@
/* POSIX compatible signal blocking.
Copyright (C) 2008-2011 Free Software Foundation, Inc.
Written by Eric Blake <ebb9@byu.net>, 2008.
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 3 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.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include <config.h>
/* Specification. */
#include <signal.h>
#include <errno.h>
#include <stdint.h>
#include <stdlib.h>
/* This implementation of sigaction is tailored to Woe32 behavior:
signal() has SysV semantics (ie. the handler is uninstalled before
it is invoked). This is an inherent data race if an asynchronous
signal is sent twice in a row before we can reinstall our handler,
but there's nothing we can do about it. Meanwhile, sigprocmask()
is not present, and while we can use the gnulib replacement to
provide critical sections, it too suffers from potential data races
in the face of an ill-timed asynchronous signal. And we compound
the situation by reading static storage in a signal handler, which
POSIX warns is not generically async-signal-safe. Oh well.
Additionally:
- We don't implement SA_NOCLDSTOP or SA_NOCLDWAIT, because SIGCHLD
is not defined.
- We don't implement SA_ONSTACK, because sigaltstack() is not present.
- We ignore SA_RESTART, because blocking Win32 calls are not interrupted
anyway when an asynchronous signal occurs, and the MSVCRT runtime
never sets errno to EINTR.
- We don't implement SA_SIGINFO because it is impossible to do so
portably.
POSIX states that an application should not mix signal() and
sigaction(). We support the use of signal() within the gnulib
sigprocmask() substitute, but all other application code linked
with this module should stick with only sigaction(). */
/* Check some of our assumptions. */
#if defined SIGCHLD || defined HAVE_SIGALTSTACK || defined HAVE_SIGINTERRUPT
# error "Revisit the assumptions made in the sigaction module"
#endif
/* Out-of-range substitutes make a good fallback for uncatchable
signals. */
#ifndef SIGKILL
# define SIGKILL (-1)
#endif
#ifndef SIGSTOP
# define SIGSTOP (-1)
#endif
/* On native Windows, as of 2008, the signal SIGABRT_COMPAT is an alias
for the signal SIGABRT. Only one signal handler is stored for both
SIGABRT and SIGABRT_COMPAT. SIGABRT_COMPAT is not a signal of its own. */
#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
# undef SIGABRT_COMPAT
# define SIGABRT_COMPAT 6
#endif
/* A signal handler. */
typedef void (*handler_t) (int signal);
/* Set of current actions. If sa_handler for an entry is NULL, then
that signal is not currently handled by the sigaction handler. */
static struct sigaction volatile action_array[NSIG] /* = 0 */;
/* Signal handler that is installed for signals. */
static void
sigaction_handler (int sig)
{
handler_t handler;
sigset_t mask;
sigset_t oldmask;
int saved_errno = errno;
if (sig < 0 || NSIG <= sig || !action_array[sig].sa_handler)
{
/* Unexpected situation; be careful to avoid recursive abort. */
if (sig == SIGABRT)
signal (SIGABRT, SIG_DFL);
abort ();
}
/* Reinstall the signal handler when required; otherwise update the
bookkeeping so that the user's handler may call sigaction and get
accurate results. We know the signal isn't currently blocked, or
we wouldn't be in its handler, therefore we know that we are not
interrupting a sigaction() call. There is a race where any
asynchronous instance of the same signal occurring before we
reinstall the handler will trigger the default handler; oh
well. */
handler = action_array[sig].sa_handler;
if ((action_array[sig].sa_flags & SA_RESETHAND) == 0)
signal (sig, sigaction_handler);
else
action_array[sig].sa_handler = NULL;
/* Block appropriate signals. */
mask = action_array[sig].sa_mask;
if ((action_array[sig].sa_flags & SA_NODEFER) == 0)
sigaddset (&mask, sig);
sigprocmask (SIG_BLOCK, &mask, &oldmask);
/* Invoke the user's handler, then restore prior mask. */
errno = saved_errno;
handler (sig);
saved_errno = errno;
sigprocmask (SIG_SETMASK, &oldmask, NULL);
errno = saved_errno;
}
/* Change and/or query the action that will be taken on delivery of
signal SIG. If not NULL, ACT describes the new behavior. If not
NULL, OACT is set to the prior behavior. Return 0 on success, or
set errno and return -1 on failure. */
int
sigaction (int sig, const struct sigaction *restrict act,
struct sigaction *restrict oact)
{
sigset_t mask;
sigset_t oldmask;
int saved_errno;
if (sig < 0 || NSIG <= sig || sig == SIGKILL || sig == SIGSTOP
|| (act && act->sa_handler == SIG_ERR))
{
errno = EINVAL;
return -1;
}
#ifdef SIGABRT_COMPAT
if (sig == SIGABRT_COMPAT)
sig = SIGABRT;
#endif
/* POSIX requires sigaction() to be async-signal-safe. In other
words, if an asynchronous signal can occur while we are anywhere
inside this function, the user's handler could then call
sigaction() recursively and expect consistent results. We meet
this rule by using sigprocmask to block all signals before
modifying any data structure that could be read from a signal
handler; this works since we know that the gnulib sigprocmask
replacement does not try to use sigaction() from its handler. */
if (!act && !oact)
return 0;
sigfillset (&mask);
sigprocmask (SIG_BLOCK, &mask, &oldmask);
if (oact)
{
if (action_array[sig].sa_handler)
*oact = action_array[sig];
else
{
/* Safe to change the handler at will here, since all
signals are currently blocked. */
oact->sa_handler = signal (sig, SIG_DFL);
if (oact->sa_handler == SIG_ERR)
goto failure;
signal (sig, oact->sa_handler);
oact->sa_flags = SA_RESETHAND | SA_NODEFER;
sigemptyset (&oact->sa_mask);
}
}
if (act)
{
/* Safe to install the handler before updating action_array,
since all signals are currently blocked. */
if (act->sa_handler == SIG_DFL || act->sa_handler == SIG_IGN)
{
if (signal (sig, act->sa_handler) == SIG_ERR)
goto failure;
action_array[sig].sa_handler = NULL;
}
else
{
if (signal (sig, sigaction_handler) == SIG_ERR)
goto failure;
action_array[sig] = *act;
}
}
sigprocmask (SIG_SETMASK, &oldmask, NULL);
return 0;
failure:
saved_errno = errno;
sigprocmask (SIG_SETMASK, &oldmask, NULL);
errno = saved_errno;
return -1;
}

376
lib/signal.in.h

@ -0,0 +1,376 @@
/* A GNU-like <signal.h>.
Copyright (C) 2006-2011 Free Software Foundation, Inc.
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 3 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.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
#if __GNUC__ >= 3
@PRAGMA_SYSTEM_HEADER@
#endif
@PRAGMA_COLUMNS@
#if defined __need_sig_atomic_t || defined __need_sigset_t
/* Special invocation convention inside glibc header files. */
# @INCLUDE_NEXT@ @NEXT_SIGNAL_H@
#else
/* Normal invocation convention. */
#ifndef _@GUARD_PREFIX@_SIGNAL_H
/* The include_next requires a split double-inclusion guard. */
#@INCLUDE_NEXT@ @NEXT_SIGNAL_H@
#ifndef _@GUARD_PREFIX@_SIGNAL_H
#define _@GUARD_PREFIX@_SIGNAL_H
/* The definitions of _GL_FUNCDECL_RPL etc. are copied here. */
/* The definition of _GL_ARG_NONNULL is copied here. */
/* The definition of _GL_WARN_ON_USE is copied here. */
/* Define pid_t, uid_t.
Also, mingw defines sigset_t not in <signal.h>, but in <sys/types.h>. */
#include <sys/types.h>
/* On AIX, sig_atomic_t already includes volatile. C99 requires that
'volatile sig_atomic_t' ignore the extra modifier, but C89 did not.
Hence, redefine this to a non-volatile type as needed. */
#if ! @HAVE_TYPE_VOLATILE_SIG_ATOMIC_T@
# if !GNULIB_defined_sig_atomic_t
typedef int rpl_sig_atomic_t;
# undef sig_atomic_t
# define sig_atomic_t rpl_sig_atomic_t
# define GNULIB_defined_sig_atomic_t 1
# endif
#endif
/* A set or mask of signals. */
#if !@HAVE_SIGSET_T@
# if !GNULIB_defined_sigset_t
typedef unsigned int sigset_t;
# define GNULIB_defined_sigset_t 1
# endif
#endif
/* Define sighandler_t, the type of signal handlers. A GNU extension. */
#if !@HAVE_SIGHANDLER_T@
# ifdef __cplusplus
extern "C" {
# endif
# if !GNULIB_defined_sighandler_t
typedef void (*sighandler_t) (int);
# define GNULIB_defined_sighandler_t 1
# endif
# ifdef __cplusplus
}
# endif
#endif
#if @GNULIB_SIGNAL_H_SIGPIPE@
# ifndef SIGPIPE
/* Define SIGPIPE to a value that does not overlap with other signals. */
# define SIGPIPE 13
# define GNULIB_defined_SIGPIPE 1
/* To actually use SIGPIPE, you also need the gnulib modules 'sigprocmask',
'write', 'stdio'. */
# endif
#endif
/* Maximum signal number + 1. */
#ifndef NSIG
# if defined __TANDEM
# define NSIG 32
# endif
#endif
#if @GNULIB_SIGPROCMASK@
# if !@HAVE_POSIX_SIGNALBLOCKING@
/* Maximum signal number + 1. */
# ifndef NSIG
# define NSIG 32
# endif
/* This code supports only 32 signals. */
# if !GNULIB_defined_verify_NSIG_constraint
typedef int verify_NSIG_constraint[NSIG <= 32 ? 1 : -1];
# define GNULIB_defined_verify_NSIG_constraint 1
# endif
# endif
/* Test whether a given signal is contained in a signal set. */
# if @HAVE_POSIX_SIGNALBLOCKING@
/* This function is defined as a macro on MacOS X. */
# if defined __cplusplus && defined GNULIB_NAMESPACE
# undef sigismember
# endif
# else
_GL_FUNCDECL_SYS (sigismember, int, (const sigset_t *set, int sig)
_GL_ARG_NONNULL ((1)));
# endif
_GL_CXXALIAS_SYS (sigismember, int, (const sigset_t *set, int sig));
_GL_CXXALIASWARN (sigismember);
/* Initialize a signal set to the empty set. */
# if @HAVE_POSIX_SIGNALBLOCKING@
/* This function is defined as a macro on MacOS X. */
# if defined __cplusplus && defined GNULIB_NAMESPACE
# undef sigemptyset
# endif
# else
_GL_FUNCDECL_SYS (sigemptyset, int, (sigset_t *set) _GL_ARG_NONNULL ((1)));
# endif
_GL_CXXALIAS_SYS (sigemptyset, int, (sigset_t *set));
_GL_CXXALIASWARN (sigemptyset);
/* Add a signal to a signal set. */
# if @HAVE_POSIX_SIGNALBLOCKING@
/* This function is defined as a macro on MacOS X. */
# if defined __cplusplus && defined GNULIB_NAMESPACE
# undef sigaddset
# endif
# else
_GL_FUNCDECL_SYS (sigaddset, int, (sigset_t *set, int sig)
_GL_ARG_NONNULL ((1)));
# endif
_GL_CXXALIAS_SYS (sigaddset, int, (sigset_t *set, int sig));
_GL_CXXALIASWARN (sigaddset);
/* Remove a signal from a signal set. */
# if @HAVE_POSIX_SIGNALBLOCKING@
/* This function is defined as a macro on MacOS X. */
# if defined __cplusplus && defined GNULIB_NAMESPACE
# undef sigdelset
# endif
# else
_GL_FUNCDECL_SYS (sigdelset, int, (sigset_t *set, int sig)
_GL_ARG_NONNULL ((1)));
# endif
_GL_CXXALIAS_SYS (sigdelset, int, (sigset_t *set, int sig));
_GL_CXXALIASWARN (sigdelset);
/* Fill a signal set with all possible signals. */
# if @HAVE_POSIX_SIGNALBLOCKING@
/* This function is defined as a macro on MacOS X. */
# if defined __cplusplus && defined GNULIB_NAMESPACE
# undef sigfillset
# endif
# else
_GL_FUNCDECL_SYS (sigfillset, int, (sigset_t *set) _GL_ARG_NONNULL ((1)));
# endif
_GL_CXXALIAS_SYS (sigfillset, int, (sigset_t *set));
_GL_CXXALIASWARN (sigfillset);
/* Return the set of those blocked signals that are pending. */
# if !@HAVE_POSIX_SIGNALBLOCKING@
_GL_FUNCDECL_SYS (sigpending, int, (sigset_t *set) _GL_ARG_NONNULL ((1)));
# endif
_GL_CXXALIAS_SYS (sigpending, int, (sigset_t *set));
_GL_CXXALIASWARN (sigpending);
/* If OLD_SET is not NULL, put the current set of blocked signals in *OLD_SET.
Then, if SET is not NULL, affect the current set of blocked signals by
combining it with *SET as indicated in OPERATION.
In this implementation, you are not allowed to change a signal handler
while the signal is blocked. */
# if !@HAVE_POSIX_SIGNALBLOCKING@
# define SIG_BLOCK 0 /* blocked_set = blocked_set | *set; */
# define SIG_SETMASK 1 /* blocked_set = *set; */
# define SIG_UNBLOCK 2 /* blocked_set = blocked_set & ~*set; */
_GL_FUNCDECL_SYS (sigprocmask, int,
(int operation, const sigset_t *set, sigset_t *old_set));
# endif
_GL_CXXALIAS_SYS (sigprocmask, int,
(int operation, const sigset_t *set, sigset_t *old_set));
_GL_CXXALIASWARN (sigprocmask);
/* Install the handler FUNC for signal SIG, and return the previous
handler. */
# ifdef __cplusplus
extern "C" {
# endif
# if !GNULIB_defined_function_taking_int_returning_void_t
typedef void (*_gl_function_taking_int_returning_void_t) (int);
# define GNULIB_defined_function_taking_int_returning_void_t 1
# endif
# ifdef __cplusplus
}
# endif
# if !@HAVE_POSIX_SIGNALBLOCKING@
# if !(defined __cplusplus && defined GNULIB_NAMESPACE)
# define signal rpl_signal
# endif
_GL_FUNCDECL_RPL (signal, _gl_function_taking_int_returning_void_t,
(int sig, _gl_function_taking_int_returning_void_t func));
_GL_CXXALIAS_RPL (signal, _gl_function_taking_int_returning_void_t,
(int sig, _gl_function_taking_int_returning_void_t func));
# else
_GL_CXXALIAS_SYS (signal, _gl_function_taking_int_returning_void_t,
(int sig, _gl_function_taking_int_returning_void_t func));
# endif
_GL_CXXALIASWARN (signal);
/* Raise signal SIG. */
# if !@HAVE_POSIX_SIGNALBLOCKING@ && GNULIB_defined_SIGPIPE
# if !(defined __cplusplus && defined GNULIB_NAMESPACE)
# undef raise
# define raise rpl_raise
# endif
_GL_FUNCDECL_RPL (raise, int, (int sig));
_GL_CXXALIAS_RPL (raise, int, (int sig));
# else
_GL_CXXALIAS_SYS (raise, int, (int sig));
# endif
_GL_CXXALIASWARN (raise);
#elif defined GNULIB_POSIXCHECK
# undef sigaddset
# if HAVE_RAW_DECL_SIGADDSET
_GL_WARN_ON_USE (sigaddset, "sigaddset is unportable - "
"use the gnulib module sigprocmask for portability");
# endif
# undef sigdelset
# if HAVE_RAW_DECL_SIGDELSET
_GL_WARN_ON_USE (sigdelset, "sigdelset is unportable - "
"use the gnulib module sigprocmask for portability");
# endif
# undef sigemptyset
# if HAVE_RAW_DECL_SIGEMPTYSET
_GL_WARN_ON_USE (sigemptyset, "sigemptyset is unportable - "
"use the gnulib module sigprocmask for portability");
# endif
# undef sigfillset
# if HAVE_RAW_DECL_SIGFILLSET
_GL_WARN_ON_USE (sigfillset, "sigfillset is unportable - "
"use the gnulib module sigprocmask for portability");
# endif
# undef sigismember
# if HAVE_RAW_DECL_SIGISMEMBER
_GL_WARN_ON_USE (sigismember, "sigismember is unportable - "
"use the gnulib module sigprocmask for portability");
# endif
# undef sigpending
# if HAVE_RAW_DECL_SIGPENDING
_GL_WARN_ON_USE (sigpending, "sigpending is unportable - "
"use the gnulib module sigprocmask for portability");
# endif
# undef sigprocmask
# if HAVE_RAW_DECL_SIGPROCMASK
_GL_WARN_ON_USE (sigprocmask, "sigprocmask is unportable - "
"use the gnulib module sigprocmask for portability");
# endif
#endif /* @GNULIB_SIGPROCMASK@ */
#if @GNULIB_SIGACTION@
# if !@HAVE_SIGACTION@
# if !@HAVE_SIGINFO_T@
# if !GNULIB_defined_siginfo_types
/* Present to allow compilation, but unsupported by gnulib. */
union sigval
{
int sival_int;
void *sival_ptr;
};
/* Present to allow compilation, but unsupported by gnulib. */
struct siginfo_t
{
int si_signo;
int si_code;
int si_errno;
pid_t si_pid;
uid_t si_uid;
void *si_addr;
int si_status;
long si_band;
union sigval si_value;
};
typedef struct siginfo_t siginfo_t;
# define GNULIB_defined_siginfo_types 1
# endif
# endif /* !@HAVE_SIGINFO_T@ */
/* We assume that platforms which lack the sigaction() function also lack
the 'struct sigaction' type, and vice versa. */
# if !GNULIB_defined_struct_sigaction
struct sigaction
{
union
{
void (*_sa_handler) (int);
/* Present to allow compilation, but unsupported by gnulib. POSIX
says that implementations may, but not must, make sa_sigaction
overlap with sa_handler, but we know of no implementation where
they do not overlap. */
void (*_sa_sigaction) (int, siginfo_t *, void *);
} _sa_func;
sigset_t sa_mask;
/* Not all POSIX flags are supported. */
int sa_flags;
};
# define sa_handler _sa_func._sa_handler
# define sa_sigaction _sa_func._sa_sigaction
/* Unsupported flags are not present. */
# define SA_RESETHAND 1
# define SA_NODEFER 2
# define SA_RESTART 4
# define GNULIB_defined_struct_sigaction 1
# endif
_GL_FUNCDECL_SYS (sigaction, int, (int, const struct sigaction *restrict,
struct sigaction *restrict));
# elif !@HAVE_STRUCT_SIGACTION_SA_SIGACTION@
# define sa_sigaction sa_handler
# endif /* !@HAVE_SIGACTION@, !@HAVE_STRUCT_SIGACTION_SA_SIGACTION@ */
_GL_CXXALIAS_SYS (sigaction, int, (int, const struct sigaction *restrict,
struct sigaction *restrict));
_GL_CXXALIASWARN (sigaction);
#elif defined GNULIB_POSIXCHECK
# undef sigaction
# if HAVE_RAW_DECL_SIGACTION
_GL_WARN_ON_USE (sigaction, "sigaction is unportable - "
"use the gnulib module sigaction for portability");
# endif
#endif
/* Some systems don't have SA_NODEFER. */
#ifndef SA_NODEFER
# define SA_NODEFER 0
#endif
#endif /* _@GUARD_PREFIX@_SIGNAL_H */
#endif /* _@GUARD_PREFIX@_SIGNAL_H */
#endif

329
lib/sigprocmask.c

@ -0,0 +1,329 @@
/* POSIX compatible signal blocking.
Copyright (C) 2006-2011 Free Software Foundation, Inc.
Written by Bruno Haible <bruno@clisp.org>, 2006.
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 3 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.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include <config.h>
/* Specification. */
#include <signal.h>
#include <errno.h>
#include <stdint.h>
#include <stdlib.h>
/* We assume that a platform without POSIX signal blocking functions
also does not have the POSIX sigaction() function, only the
signal() function. We also assume signal() has SysV semantics,
where any handler is uninstalled prior to being invoked. This is
true for Woe32 platforms. */
/* We use raw signal(), but also provide a wrapper rpl_signal() so
that applications can query or change a blocked signal. */
#undef signal
/* Provide invalid signal numbers as fallbacks if the uncatchable
signals are not defined. */
#ifndef SIGKILL
# define SIGKILL (-1)
#endif
#ifndef SIGSTOP
# define SIGSTOP (-1)
#endif
/* On native Windows, as of 2008, the signal SIGABRT_COMPAT is an alias
for the signal SIGABRT. Only one signal handler is stored for both
SIGABRT and SIGABRT_COMPAT. SIGABRT_COMPAT is not a signal of its own. */
#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
# undef SIGABRT_COMPAT
# define SIGABRT_COMPAT 6
#endif
#ifdef SIGABRT_COMPAT
# define SIGABRT_COMPAT_MASK (1U << SIGABRT_COMPAT)
#else
# define SIGABRT_COMPAT_MASK 0
#endif
typedef void (*handler_t) (int);
/* Handling of gnulib defined signals. */
#if GNULIB_defined_SIGPIPE
static handler_t SIGPIPE_handler = SIG_DFL;
#endif
#if GNULIB_defined_SIGPIPE
static handler_t
ext_signal (int sig, handler_t handler)
{
switch (sig)
{
case SIGPIPE:
{
handler_t old_handler = SIGPIPE_handler;
SIGPIPE_handler = handler;
return old_handler;
}
default: /* System defined signal */
return signal (sig, handler);
}
}
# define signal ext_signal
#endif
int
sigismember (const sigset_t *set, int sig)
{
if (sig >= 0 && sig < NSIG)
{
#ifdef SIGABRT_COMPAT
if (sig == SIGABRT_COMPAT)
sig = SIGABRT;
#endif
return (*set >> sig) & 1;
}
else
return 0;
}
int
sigemptyset (sigset_t *set)
{
*set = 0;
return 0;
}
int
sigaddset (sigset_t *set, int sig)
{
if (sig >= 0 && sig < NSIG)
{
#ifdef SIGABRT_COMPAT
if (sig == SIGABRT_COMPAT)
sig = SIGABRT;
#endif
*set |= 1U << sig;
return 0;
}
else
{
errno = EINVAL;
return -1;
}
}
int
sigdelset (sigset_t *set, int sig)
{
if (sig >= 0 && sig < NSIG)
{
#ifdef SIGABRT_COMPAT
if (sig == SIGABRT_COMPAT)
sig = SIGABRT;
#endif
*set &= ~(1U << sig);
return 0;
}
else
{
errno = EINVAL;
return -1;
}
}
int
sigfillset (sigset_t *set)
{
*set = ((2U << (NSIG - 1)) - 1) & ~ SIGABRT_COMPAT_MASK;
return 0;
}
/* Set of currently blocked signals. */
static volatile sigset_t blocked_set /* = 0 */;
/* Set of currently blocked and pending signals. */
static volatile sig_atomic_t pending_array[NSIG] /* = { 0 } */;
/* Signal handler that is installed for blocked signals. */
static void
blocked_handler (int sig)
{
/* Reinstall the handler, in case the signal occurs multiple times
while blocked. There is an inherent race where an asynchronous
signal in between when the kernel uninstalled the handler and
when we reinstall it will trigger the default handler; oh
well. */
signal (sig, blocked_handler);
if (sig >= 0 && sig < NSIG)
pending_array[sig] = 1;
}
int
sigpending (sigset_t *set)
{
sigset_t pending = 0;
int sig;
for (sig = 0; sig < NSIG; sig++)
if (pending_array[sig])
pending |= 1U << sig;
*set = pending;
return 0;
}
/* The previous signal handlers.
Only the array elements corresponding to blocked signals are relevant. */
static volatile handler_t old_handlers[NSIG];
int
sigprocmask (int operation, const sigset_t *set, sigset_t *old_set)
{
if (old_set != NULL)
*old_set = blocked_set;
if (set != NULL)
{
sigset_t new_blocked_set;
sigset_t to_unblock;
sigset_t to_block;
switch (operation)
{
case SIG_BLOCK:
new_blocked_set = blocked_set | *set;
break;
case SIG_SETMASK:
new_blocked_set = *set;
break;
case SIG_UNBLOCK:
new_blocked_set = blocked_set & ~*set;
break;
default:
errno = EINVAL;
return -1;
}
to_unblock = blocked_set & ~new_blocked_set;
to_block = new_blocked_set & ~blocked_set;
if (to_block != 0)
{
int sig;
for (sig = 0; sig < NSIG; sig++)
if ((to_block >> sig) & 1)
{
pending_array[sig] = 0;
if ((old_handlers[sig] = signal (sig, blocked_handler)) != SIG_ERR)
blocked_set |= 1U << sig;
}
}
if (to_unblock != 0)
{
sig_atomic_t received[NSIG];
int sig;
for (sig = 0; sig < NSIG; sig++)
if ((to_unblock >> sig) & 1)
{
if (signal (sig, old_handlers[sig]) != blocked_handler)
/* The application changed a signal handler while the signal
was blocked, bypassing our rpl_signal replacement.
We don't support this. */
abort ();
received[sig] = pending_array[sig];
blocked_set &= ~(1U << sig);
pending_array[sig] = 0;
}
else
received[sig] = 0;
for (sig = 0; sig < NSIG; sig++)
if (received[sig])
raise (sig);
}
}
return 0;
}
/* Install the handler FUNC for signal SIG, and return the previous
handler. */
handler_t
rpl_signal (int sig, handler_t handler)
{
/* We must provide a wrapper, so that a user can query what handler
they installed even if that signal is currently blocked. */
if (sig >= 0 && sig < NSIG && sig != SIGKILL && sig != SIGSTOP
&& handler != SIG_ERR)
{
#ifdef SIGABRT_COMPAT
if (sig == SIGABRT_COMPAT)
sig = SIGABRT;
#endif
if (blocked_set & (1U << sig))
{
/* POSIX states that sigprocmask and signal are both
async-signal-safe. This is not true of our
implementation - there is a slight data race where an
asynchronous interrupt on signal A can occur after we
install blocked_handler but before we have updated
old_handlers for signal B, such that handler A can see
stale information if it calls signal(B). Oh well -
signal handlers really shouldn't try to manipulate the
installed handlers of unrelated signals. */
handler_t result = old_handlers[sig];
old_handlers[sig] = handler;
return result;
}
else
return signal (sig, handler);
}
else
{
errno = EINVAL;
return SIG_ERR;
}
}
#if GNULIB_defined_SIGPIPE
/* Raise the signal SIG. */
int
rpl_raise (int sig)
# undef raise
{
switch (sig)
{
case SIGPIPE:
if (blocked_set & (1U << sig))
pending_array[sig] = 1;
else
{
handler_t handler = SIGPIPE_handler;
if (handler == SIG_DFL)
exit (128 + SIGPIPE);
else if (handler != SIG_IGN)
(*handler) (sig);
}
return 0;
default: /* System defined signal */
return raise (sig);
}
}
#endif

0
m4/.gitignore vendored

5
m4/gnulib-cache.m4

@ -15,12 +15,14 @@
# Specification in the form of a command-line invocation: # Specification in the form of a command-line invocation:
# gnulib-tool --import --dir=. --lib=libgnu --source-base=lib --m4-base=m4 --doc-base=doc --tests-base=tests --aux-dir=. --no-conditional-dependencies --no-libtool --macro-prefix=gl memmem # gnulib-tool --import --dir=. --lib=libgnu --source-base=lib --m4-base=m4 --doc-base=doc --tests-base=tests --aux-dir=. --no-conditional-dependencies --no-libtool --macro-prefix=gl --no-vc-files memmem sigaction signal
# Specification in the form of a few gnulib-tool.m4 macro invocations: # Specification in the form of a few gnulib-tool.m4 macro invocations:
gl_LOCAL_DIR([]) gl_LOCAL_DIR([])
gl_MODULES([ gl_MODULES([
memmem memmem
sigaction
signal
]) ])
gl_AVOID([]) gl_AVOID([])
gl_SOURCE_BASE([lib]) gl_SOURCE_BASE([lib])
@ -33,3 +35,4 @@ gl_MAKEFILE_NAME([])
gl_MACRO_PREFIX([gl]) gl_MACRO_PREFIX([gl])
gl_PO_DOMAIN([]) gl_PO_DOMAIN([])
gl_WITNESS_C_DOMAIN([]) gl_WITNESS_C_DOMAIN([])
gl_VC_FILES([false])

24
m4/gnulib-comp.m4

@ -15,6 +15,7 @@
# In projects that use version control, this file can be treated like # In projects that use version control, this file can be treated like
# other built files. # other built files.
# This macro should be invoked from ./configure.ac, in the section # This macro should be invoked from ./configure.ac, in the section
# "Checks for programs", right after AC_PROG_CC, and certainly before # "Checks for programs", right after AC_PROG_CC, and certainly before
# any checks for libraries, header files, types and library functions. # any checks for libraries, header files, types and library functions.
@ -34,6 +35,9 @@ AC_DEFUN([gl_EARLY],
# Code from module memmem: # Code from module memmem:
# Code from module memmem-simple: # Code from module memmem-simple:
# Code from module multiarch: # Code from module multiarch:
# Code from module sigaction:
# Code from module signal:
# Code from module sigprocmask:
# Code from module stddef: # Code from module stddef:
# Code from module stdint: # Code from module stdint:
# Code from module string: # Code from module string:
@ -72,6 +76,19 @@ if test $HAVE_MEMMEM = 0 || test $REPLACE_MEMMEM = 1; then
fi fi
gl_STRING_MODULE_INDICATOR([memmem]) gl_STRING_MODULE_INDICATOR([memmem])
gl_MULTIARCH gl_MULTIARCH
gl_SIGACTION
if test $HAVE_SIGACTION = 0; then
AC_LIBOBJ([sigaction])
gl_PREREQ_SIGACTION
fi
gl_SIGNAL_MODULE_INDICATOR([sigaction])
gl_SIGNAL_H
gl_SIGNALBLOCKING
if test $HAVE_POSIX_SIGNALBLOCKING = 0; then
AC_LIBOBJ([sigprocmask])
gl_PREREQ_SIGPROCMASK
fi
gl_SIGNAL_MODULE_INDICATOR([sigprocmask])
gl_STDDEF_H gl_STDDEF_H
gl_STDINT_H gl_STDINT_H
gl_HEADER_STRING_H gl_HEADER_STRING_H
@ -222,6 +239,10 @@ AC_DEFUN([gl_FILE_LIST], [
lib/memchr.c lib/memchr.c
lib/memchr.valgrind lib/memchr.valgrind
lib/memmem.c lib/memmem.c
lib/sig-handler.h
lib/sigaction.c
lib/signal.in.h
lib/sigprocmask.c
lib/stddef.in.h lib/stddef.in.h
lib/stdint.in.h lib/stdint.in.h
lib/str-two-way.h lib/str-two-way.h
@ -236,6 +257,9 @@ AC_DEFUN([gl_FILE_LIST], [
m4/mmap-anon.m4 m4/mmap-anon.m4
m4/multiarch.m4 m4/multiarch.m4
m4/onceonly.m4 m4/onceonly.m4
m4/sigaction.m4
m4/signal_h.m4
m4/signalblocking.m4
m4/stddef_h.m4 m4/stddef_h.m4
m4/stdint.m4 m4/stdint.m4
m4/string_h.m4 m4/string_h.m4

43
m4/sigaction.m4

@ -0,0 +1,43 @@
# sigaction.m4 serial 6
dnl Copyright (C) 2008-2011 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
dnl with or without modifications, as long as this notice is preserved.
# Determine if sigaction interface is present.
AC_DEFUN([gl_SIGACTION],
[
AC_REQUIRE([gl_SIGNAL_H_DEFAULTS])
AC_CHECK_FUNCS_ONCE([sigaction])
if test $ac_cv_func_sigaction = yes; then
AC_CHECK_MEMBERS([struct sigaction.sa_sigaction], , ,
[[#include <signal.h>]])
if test $ac_cv_member_struct_sigaction_sa_sigaction = no; then
HAVE_STRUCT_SIGACTION_SA_SIGACTION=0
fi
else
HAVE_SIGACTION=0
fi
])
# Prerequisites of the part of lib/signal.in.h and of lib/sigaction.c.
AC_DEFUN([gl_PREREQ_SIGACTION],
[
AC_REQUIRE([gl_SIGNAL_H_DEFAULTS])
AC_REQUIRE([AC_C_RESTRICT])
AC_REQUIRE([AC_TYPE_UID_T])
AC_REQUIRE([gl_PREREQ_SIG_HANDLER_H])
AC_CHECK_FUNCS_ONCE([sigaltstack siginterrupt])
AC_CHECK_TYPES([siginfo_t], [], [], [[
#include <signal.h>
]])
if test $ac_cv_type_siginfo_t = no; then
HAVE_SIGINFO_T=0
fi
])
# Prerequisites of lib/sig-handler.h.
AC_DEFUN([gl_PREREQ_SIG_HANDLER_H],
[
AC_REQUIRE([AC_C_INLINE])
])

58
m4/signal_h.m4

@ -0,0 +1,58 @@
# signal_h.m4 serial 12
dnl Copyright (C) 2007-2011 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
dnl with or without modifications, as long as this notice is preserved.
AC_DEFUN([gl_SIGNAL_H],
[
AC_REQUIRE([gl_SIGNAL_H_DEFAULTS])
gl_NEXT_HEADERS([signal.h])
# AIX declares sig_atomic_t to already include volatile, and C89 compilers
# then choke on 'volatile sig_atomic_t'. C99 requires that it compile.
AC_CHECK_TYPE([volatile sig_atomic_t], [],
[HAVE_TYPE_VOLATILE_SIG_ATOMIC_T=0], [[
#include <signal.h>
]])
AC_REQUIRE([AC_TYPE_UID_T])
dnl Persuade glibc <signal.h> to define sighandler_t.
AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])
AC_CHECK_TYPE([sighandler_t], [], [HAVE_SIGHANDLER_T=0], [[
#include <signal.h>
]])
dnl Check for declarations of anything we want to poison if the
dnl corresponding gnulib module is not in use.
gl_WARN_ON_USE_PREPARE([[#include <signal.h>
]], [sigaction sigaddset sigdelset sigemptyset sigfillset sigismember
sigpending sigprocmask])
])
AC_DEFUN([gl_SIGNAL_MODULE_INDICATOR],
[
dnl Use AC_REQUIRE here, so that the default settings are expanded once only.
AC_REQUIRE([gl_SIGNAL_H_DEFAULTS])
gl_MODULE_INDICATOR_SET_VARIABLE([$1])
dnl Define it also as a C macro, for the benefit of the unit tests.
gl_MODULE_INDICATOR_FOR_TESTS([$1])
])
AC_DEFUN([gl_SIGNAL_H_DEFAULTS],
[
GNULIB_SIGNAL_H_SIGPIPE=0; AC_SUBST([GNULIB_SIGNAL_H_SIGPIPE])
GNULIB_SIGPROCMASK=0; AC_SUBST([GNULIB_SIGPROCMASK])
GNULIB_SIGACTION=0; AC_SUBST([GNULIB_SIGACTION])
dnl Assume proper GNU behavior unless another module says otherwise.
HAVE_POSIX_SIGNALBLOCKING=1; AC_SUBST([HAVE_POSIX_SIGNALBLOCKING])
HAVE_SIGSET_T=1; AC_SUBST([HAVE_SIGSET_T])
HAVE_SIGINFO_T=1; AC_SUBST([HAVE_SIGINFO_T])
HAVE_SIGACTION=1; AC_SUBST([HAVE_SIGACTION])
HAVE_STRUCT_SIGACTION_SA_SIGACTION=1;
AC_SUBST([HAVE_STRUCT_SIGACTION_SA_SIGACTION])
HAVE_TYPE_VOLATILE_SIG_ATOMIC_T=1;
AC_SUBST([HAVE_TYPE_VOLATILE_SIG_ATOMIC_T])
HAVE_SIGHANDLER_T=1; AC_SUBST([HAVE_SIGHANDLER_T])
])

40
m4/signalblocking.m4

@ -0,0 +1,40 @@
# signalblocking.m4 serial 11
dnl Copyright (C) 2001-2002, 2006-2011 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
dnl with or without modifications, as long as this notice is preserved.
# Determine available signal blocking primitives. Three different APIs exist:
# 1) POSIX: sigemptyset, sigaddset, sigprocmask
# 2) SYSV: sighold, sigrelse
# 3) BSD: sigblock, sigsetmask
# For simplicity, here we check only for the POSIX signal blocking.
AC_DEFUN([gl_SIGNALBLOCKING],
[
AC_REQUIRE([gl_SIGNAL_H_DEFAULTS])
signals_not_posix=
AC_EGREP_HEADER([sigset_t], [signal.h], , [signals_not_posix=1])
if test -z "$signals_not_posix"; then
AC_CHECK_FUNC([sigprocmask], [gl_cv_func_sigprocmask=1])
fi
if test -z "$gl_cv_func_sigprocmask"; then
HAVE_POSIX_SIGNALBLOCKING=0
fi
])
# Prerequisites of the part of lib/signal.in.h and of lib/sigprocmask.c.
AC_DEFUN([gl_PREREQ_SIGPROCMASK],
[
AC_REQUIRE([gl_SIGNAL_H_DEFAULTS])
AC_CHECK_TYPES([sigset_t],
[gl_cv_type_sigset_t=yes], [gl_cv_type_sigset_t=no],
[#include <signal.h>
/* Mingw defines sigset_t not in <signal.h>, but in <sys/types.h>. */
#include <sys/types.h>])
if test $gl_cv_type_sigset_t != yes; then
HAVE_SIGSET_T=0
fi
dnl HAVE_SIGSET_T is 1 if the system lacks the sigprocmask function but has
dnl the sigset_t type.
AC_SUBST([HAVE_SIGSET_T])
])
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