+2012-07-15 Paul Eggert <eggert@cs.ucla.edu>
+
+ pthread_sigmask: fix bug on FreeBSD 9
+ * lib/pthread_sigmask.c [PTHREAD_SIGMASK_INEFFECTIVE]:
+ Include string.h.
+ (pthread_sigmask) [PTHREAD_SIGMASK_INEFFECTIVE]:
+ When calling pthread_sigmask (1729, NEW, OLD), specify non-null NEW;
+ this avoids a bug on FreeBSD 9, where pthread_sigmask is effective
+ but pthread_sigmask (1729, NULL, NULL) returns zero.
+ See <http://bugs.gnu.org/11884>.
+ Avoid the need to call pthread_sigmask (1729, ...) in most cases,
+ by inspecting whether the main call changed the old mask.
+
2012-07-15 Reuben Thomas <rrt@sc3d.org>
README-release: make it more legible
#include <errno.h>
#include <stddef.h>
+#if PTHREAD_SIGMASK_INEFFECTIVE
+# include <string.h>
+#endif
+
#if PTHREAD_SIGMASK_UNBLOCK_BUG
# include <unistd.h>
#endif
#undef pthread_sigmask
{
#if HAVE_PTHREAD_SIGMASK
- int ret = pthread_sigmask (how, new_mask, old_mask);
+ int ret;
+
+# if PTHREAD_SIGMASK_INEFFECTIVE
+ sigset_t omask, omask_copy;
+ sigset_t *old_mask_ptr = &omask;
+ sigemptyset (&omask);
+ /* Add a signal unlikely to be blocked, so that OMASK_COPY
+ is unlikely to match the actual mask. */
+ sigaddset (&omask, SIGILL);
+ memcpy (&omask_copy, &omask, sizeof omask);
+# else
+ sigset_t *old_mask_ptr = old_mask;
+# endif
+
+ ret = pthread_sigmask (how, new_mask, old_mask_ptr);
+
# if PTHREAD_SIGMASK_INEFFECTIVE
if (ret == 0)
{
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)
+ if (memcmp (&omask_copy, &omask, sizeof omask) == 0
+ && pthread_sigmask (1729, &omask_copy, 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);
}
+
+ if (old_mask)
+ memcpy (old_mask, &omask, sizeof omask);
}
# endif
# if PTHREAD_SIGMASK_FAILS_WITH_ERRNO