about summary refs log tree commit diff
path: root/src/thread
diff options
context:
space:
mode:
authorRich Felker <dalias@aerifal.cx>2011-04-05 18:00:28 -0400
committerRich Felker <dalias@aerifal.cx>2011-04-05 18:00:28 -0400
commit729cb49f52c825ac44f437e1ff0865d9f0b3626a (patch)
tree18db05e36f16fcdfc1147f4ba1ea19a0ee4bea9c /src/thread
parent918a40f257328a2d7490829b54687cd38d7b787b (diff)
downloadmusl-729cb49f52c825ac44f437e1ff0865d9f0b3626a.tar.gz
musl-729cb49f52c825ac44f437e1ff0865d9f0b3626a.tar.xz
musl-729cb49f52c825ac44f437e1ff0865d9f0b3626a.zip
new framework to inhibit thread cancellation when needed
with these small changes, libc functions which need to call functions
which are cancellation points, but which themselves must not be
cancellation points, can use the CANCELPT_INHIBIT and CANCELPT_RESUME
macros to temporarily inhibit all cancellation.
Diffstat (limited to 'src/thread')
-rw-r--r--src/thread/pthread_create.c16
-rw-r--r--src/thread/pthread_setcancelstate.c4
2 files changed, 15 insertions, 5 deletions
diff --git a/src/thread/pthread_create.c b/src/thread/pthread_create.c
index 284b45a0..52487001 100644
--- a/src/thread/pthread_create.c
+++ b/src/thread/pthread_create.c
@@ -57,9 +57,19 @@ static void cancel_handler(int sig, siginfo_t *si, void *ctx)
 static void cancelpt(int x)
 {
 	struct pthread *self = __pthread_self();
-	if (self->canceldisable) return;
-	if ((self->cancelpoint+=x)==1 && x>=0 && self->cancel)
-		docancel(self);
+	switch (x) {
+	case 1:
+		self->cancelpoint++;
+	case 0:
+		if (self->cancel && self->cancelpoint==1 && !self->canceldisable)
+			docancel(self);
+		break;
+	case -1:
+		self->cancelpoint--;
+		break;
+	default:
+		self->canceldisable += x;
+	}
 }
 
 /* "rsyscall" is a mechanism by which a thread can synchronously force all
diff --git a/src/thread/pthread_setcancelstate.c b/src/thread/pthread_setcancelstate.c
index 23c38851..a85cc800 100644
--- a/src/thread/pthread_setcancelstate.c
+++ b/src/thread/pthread_setcancelstate.c
@@ -3,8 +3,8 @@
 int pthread_setcancelstate(int new, int *old)
 {
 	struct pthread *self = pthread_self();
-	if (old) *old = self->canceldisable;
+	if (old) *old = self->canceldisable & 1;
 	if ((unsigned)new > 1) return EINVAL;
-	self->canceldisable = new;
+	self->canceldisable = (self->canceldisable & ~1) | new;
 	return 0;
 }