From fc5b3a7190a490a169f2d53a54b393a68fab9ec2 Mon Sep 17 00:00:00 2001 From: Paul Eggert Date: Sun, 15 Jul 2012 11:06:11 -0700 Subject: [PATCH] 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 . Avoid the need to call pthread_sigmask (1729, ...) in most cases, by inspecting whether the main call changed the old mask. --- ChangeLog | 13 +++++++++++++ lib/pthread_sigmask.c | 27 +++++++++++++++++++++++++-- 2 files changed, 38 insertions(+), 2 deletions(-) diff --git a/ChangeLog b/ChangeLog index 169c2ecf8..1de58990e 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,16 @@ +2012-07-15 Paul Eggert + + 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 . + 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 README-release: make it more legible diff --git a/lib/pthread_sigmask.c b/lib/pthread_sigmask.c index 4a150e70e..80ab24bf0 100644 --- a/lib/pthread_sigmask.c +++ b/lib/pthread_sigmask.c @@ -22,6 +22,10 @@ #include #include +#if PTHREAD_SIGMASK_INEFFECTIVE +# include +#endif + #if PTHREAD_SIGMASK_UNBLOCK_BUG # include #endif @@ -31,7 +35,22 @@ 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); + 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) { @@ -39,12 +58,16 @@ pthread_sigmask (int how, const sigset_t *new_mask, sigset_t *old_mask) 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 -- 2.11.0