Merge from gnulib, using build-aux to remove clutter.

* m4/largefile.m4: New file, so that Emacs does not mess up when
accessing files with large inode numbers in MacOS X 10.5 and later.
* m4/nocrash.m4: New file, to avoid triggering background debugger
and/or create core dumps during 'configure'.
* build-aux/move-if-change: Renamed from move-if-change.
* build-aux/snippet/arg-nonnull.h: Renamed from arg-nonnull.h.
* build-aux/snippet/c++defs.h: Renamed from c++defs.h.
* build-aux/snippet/warn-on-use.h: Renamed from warn-on-use.h.
* build-aux/snippet/_Noreturn.h: New file, for draft C1X _Noreturn.
* .bzrignore: The autogenerated files compile, config.guess,
config.sub, depcomp, install-sh, and missing are now in build-aux.
* Makefile.in (epaths-force, sync-from-gnulib):
move-if-change is now in build-aux.
(GNULIB_TOOL_FLAGS): Avoid threadlib; this is now a prerequisite
of gnulib's pthread_sigmask module, but Emacs doesn't need it.
(mkdir): install-sh is now in build-aux.
* config.bat: c++defs.h is now in build-aux/snippets.
* configure.in: Specify AC_CONFIG_AUX_DIR with build-aux (the
usual parameter).
* lib/gnulib.mk, m4/gl-comp.m4: Regenerate.
* lib/makefile.w32-in (ARG_NONNULL_H): arg-nonnull.h moved
to build-aux/snippet.
* lib/pthread_sigmask.c, lib/stdlib.in.h, m4/extensions.m4:
* m4/getopt.m4, m4/gnulib-common.m4, m4/pthread_sigmask.m4:
Merge from gnuilib.  This fixes porting bugs on Cygwin, Irix, and
Solaris, enables MacOS extensions, and enables nocrash during
'configure'.
* make-dist: Adjust to new build-aux and build-aux/snippit dirs.
* admin/notes/copyright: The files compile, config.guess, config.sub,
depcomp, install-sh, missing, and move-if-change are now in the
new build-aux subdirectory.  The files arg-nonnull.h, c++defs.h,
and warn-on-use.h are now in build-aux/snippets.  New file
build-aux/snippets/_Noreturn.h.
* leim/Makefile.in (install): install-sh is now in build-aux.
* lib-src/Makefile.in ($(DESTDIR)${archlibdir}): install-sh moved
to build-aux.
* msdos/sedlibmk.inp (CONFIG_CLEAN_VPATH_FILES): Adjust to snippet moves
from top level to build-aux/snippet.
* src/Makefile.in (gl-stamp): move-if-change is now in build-aux.

1 files changed, 40 insertions, 0 deletions

diff --git a/lib/pthread_sigmask.c b/lib/pthread_sigmask.c
index 1f460f13c4..11d549cad4 100644
--- a/lib/pthread_sigmask.c
+++ b/lib/pthread_sigmask.c
@@ -20,10 +20,50 @@
 #include <signal.h>
 
 #include <errno.h>
+#include <stddef.h>
+
+#if PTHREAD_SIGMASK_UNBLOCK_BUG
+# include <unistd.h>
+#endif
 
 int
 pthread_sigmask (int how, const sigset_t *new_mask, sigset_t *old_mask)
+#undef pthread_sigmask
 {
+#if HAVE_PTHREAD_SIGMASK
+  int ret = pthread_sigmask (how, new_mask, old_mask);
+# if PTHREAD_SIGMASK_INEFFECTIVE
+  if (ret == 0)
+    {
+      /* Detect whether pthread_sigmask is currently ineffective.
+         Don't cache the information: libpthread.so could be dynamically
+         loaded after the program started and after pthread_sigmask was
+         called for the first time.  */
+      if (pthread_sigmask (1729, NULL, NULL) == 0)
+        {
+          /* pthread_sigmask is currently ineffective.  The program is not
+             linked to -lpthread.  So use sigprocmask instead.  */
+          return (sigprocmask (how, new_mask, old_mask) < 0 ? errno : 0);
+        }
+    }
+# endif
+# if PTHREAD_SIGMASK_FAILS_WITH_ERRNO
+  if (ret == -1)
+    return errno;
+# endif
+# if PTHREAD_SIGMASK_UNBLOCK_BUG
+  if (ret == 0
+      && new_mask != NULL
+      && (how == SIG_UNBLOCK || how == SIG_SETMASK))
+    {
+      /* Give the OS the opportunity to raise signals that were pending before
+         the pthread_sigmask call and have now been unblocked.  */
+      usleep (1);
+    }
+# endif
+  return ret;
+#else
   int ret = sigprocmask (how, new_mask, old_mask);
   return (ret < 0 ? errno : 0);
+#endif
 }