From 99b8a25e941e54537bf39ca2f265c345f393f112 Mon Sep 17 00:00:00 2001 From: Rich Felker Date: Sat, 7 May 2011 23:23:58 -0400 Subject: overhaul implementation-internal signal protections the new approach relies on the fact that the only ways to create sigset_t objects without invoking UB are to use the sig*set() functions, or from the masks returned by sigprocmask, sigaction, etc. or in the ucontext_t argument to a signal handler. thus, as long as sigfillset and sigaddset avoid adding the "protected" signals, there is no way the application will ever obtain a sigset_t including these bits, and thus no need to add the overhead of checking/clearing them when sigprocmask or sigaction is called. note that the old code actually *failed* to remove the bits from sa_mask when sigaction was called. the new implementations are also significantly smaller, simpler, and faster due to ignoring the useless "GNU HURD signals" 65-1024, which are not used and, if there's any sanity in the world, never will be used. --- src/thread/__rsyscall.c | 5 ++--- src/thread/pthread_create.c | 16 ++++------------ 2 files changed, 6 insertions(+), 15 deletions(-) (limited to 'src/thread') diff --git a/src/thread/__rsyscall.c b/src/thread/__rsyscall.c index 61d41df7..e885d9e7 100644 --- a/src/thread/__rsyscall.c +++ b/src/thread/__rsyscall.c @@ -56,8 +56,7 @@ int __rsyscall(int nr, long a, long b, long c, long d, long e, long f) while ((i=rs.blocks)) __wait(&rs.blocks, 0, i, 1); - sigfillset(&set); - __libc_sigprocmask(SIG_BLOCK, &set, &set); + __syscall(SYS_rt_sigprocmask, SIG_BLOCK, (uint64_t[]){-1}, &set, 8); if (!rs.init) { struct sigaction sa = { @@ -88,7 +87,7 @@ int __rsyscall(int nr, long a, long b, long c, long d, long e, long f) } /* Handle any lingering signals with no-op */ - __libc_sigprocmask(SIG_UNBLOCK, &set, &set); + __syscall(SYS_rt_sigprocmask, SIG_SETMASK, &set, &set, 8); /* Resume other threads' signal handlers and wait for them */ rs.hold = 0; diff --git a/src/thread/pthread_create.c b/src/thread/pthread_create.c index 0d2c17bb..6545539b 100644 --- a/src/thread/pthread_create.c +++ b/src/thread/pthread_create.c @@ -34,7 +34,7 @@ void __pthread_unwind_next(struct __ptcb *cb) if (!n) exit(0); if (self->detached && self->map_base) { - __syscall(SYS_rt_sigprocmask, SIG_BLOCK, (long)(uint64_t[1]){-1},0,8); + __syscall(SYS_rt_sigprocmask, SIG_BLOCK, (uint64_t[]){-1},0,8); __unmapself(self->map_base, self->map_size); } @@ -44,12 +44,8 @@ void __pthread_unwind_next(struct __ptcb *cb) static int start(void *p) { struct pthread *self = p; - if (self->unblock_cancel) { - sigset_t set; - sigemptyset(&set); - sigaddset(&set, SIGCANCEL); - __libc_sigprocmask(SIG_UNBLOCK, &set, 0); - } + if (self->unblock_cancel) + __syscall(SYS_rt_sigprocmask, SIG_UNBLOCK, &SIGPT_SET, 0, 8); pthread_exit(self->start(self->start_arg)); return 0; } @@ -72,11 +68,7 @@ int pthread_create(pthread_t *res, const pthread_attr_t *attr, void *(*entry)(vo if (!self) return ENOSYS; if (!libc.threaded) { - sigset_t set; - sigemptyset(&set); - sigaddset(&set, SIGSYSCALL); - sigaddset(&set, SIGCANCEL); - __libc_sigprocmask(SIG_UNBLOCK, &set, 0); + __syscall(SYS_rt_sigprocmask, SIG_UNBLOCK, &SIGPT_SET, 0, 8); libc.threaded = 1; } -- cgit v1.2.1