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| author | Rich Felker <dalias@aerifal.cx> | 2011-04-20 21:41:45 -0400 |
|---|---|---|
| committer | Rich Felker <dalias@aerifal.cx> | 2011-04-20 21:41:45 -0400 |
| commit | 870cc679771f776333953b2a990a107393d9d0fd (patch) | |
| tree | 45b6de4ba1170de4654b23d62bd1c6a38220e112 | |
| parent | f9a6372a98cc4d1b70400b2e7238e1f9eae50558 (diff) | |
| download | musl-870cc679771f776333953b2a990a107393d9d0fd.tar.gz musl-870cc679771f776333953b2a990a107393d9d0fd.tar.xz musl-870cc679771f776333953b2a990a107393d9d0fd.zip | |
fix minor bugs due to incorrect threaded-predicate semantics
some functions that should have been testing whether pthread_self() had been called and initialized the thread pointer were instead testing whether pthread_create() had been called and actually made the program "threaded". while it's unlikely any mismatch would occur in real-world problems, this could have introduced subtle bugs. now, we store the address of the main thread's thread descriptor in the libc structure and use its presence as a flag that the thread register is initialized. note that after fork, the calling thread (not necessarily the original main thread) is the new main thread.
| -rw-r--r-- | src/internal/libc.h | 1 | ||||
| -rw-r--r-- | src/process/fork.c | 3 | ||||
| -rw-r--r-- | src/thread/pthread_self.c | 6 | ||||
| -rw-r--r-- | src/thread/pthread_setcancelstate.c | 2 |
4 files changed, 6 insertions, 6 deletions
diff --git a/src/internal/libc.h b/src/internal/libc.h index 06ba73e7..638ea527 100644 --- a/src/internal/libc.h +++ b/src/internal/libc.h @@ -16,6 +16,7 @@ struct __libc { volatile int threads_minus_1; int ofl_lock; FILE *ofl_head; + void *main_thread; }; diff --git a/src/process/fork.c b/src/process/fork.c index bcd47c97..a04e8929 100644 --- a/src/process/fork.c +++ b/src/process/fork.c @@ -8,10 +8,11 @@ pid_t fork(void) pid_t ret; if (libc.fork_handler) libc.fork_handler(-1); ret = syscall(SYS_fork); - if (libc.threaded && !ret) { + if (libc.main_thread && !ret) { pthread_t self = __pthread_self(); self->tid = self->pid = syscall(SYS_getpid); libc.threads_minus_1 = 0; + libc.main_thread = self; } if (libc.fork_handler) libc.fork_handler(!ret); return ret; diff --git a/src/thread/pthread_self.c b/src/thread/pthread_self.c index e8bb9181..55d20c9f 100644 --- a/src/thread/pthread_self.c +++ b/src/thread/pthread_self.c @@ -6,7 +6,6 @@ static struct pthread main_thread; static const void *dummy[1] = { 0 }; weak_alias(dummy, __pthread_tsd_main); -#undef errno static int *errno_location() { return __pthread_self()->errno_ptr; @@ -14,11 +13,10 @@ static int *errno_location() static int init_main_thread() { + if (__set_thread_area(&main_thread) < 0) return -1; main_thread.canceldisable = libc.canceldisable; main_thread.tsd = (void **)__pthread_tsd_main; - main_thread.self = &main_thread; - if (__set_thread_area(&main_thread) < 0) - return -1; + main_thread.self = libc.main_thread = &main_thread; main_thread.errno_ptr = __errno_location(); libc.errno_location = errno_location; main_thread.tid = main_thread.pid = diff --git a/src/thread/pthread_setcancelstate.c b/src/thread/pthread_setcancelstate.c index ebb6eba4..ba2b2311 100644 --- a/src/thread/pthread_setcancelstate.c +++ b/src/thread/pthread_setcancelstate.c @@ -3,7 +3,7 @@ int pthread_setcancelstate(int new, int *old) { if (new > 1U) return EINVAL; - if (libc.threaded) { + if (libc.main_thread) { struct pthread *self = __pthread_self(); if (old) *old = self->canceldisable; self->canceldisable = new; |