X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;ds=sidebyside;f=src%2Fthread%2Fpthread_cancel.c;h=1b71aa423399220f70a0a35066af8b04d8d0339a;hb=102f6a01e249ce4495f1119ae6d963a2a4a53ce5;hp=c497dbe667d101054158d1399854f2da8469a5cc;hpb=ded6cb5f719464649bcb61624d52327ae444bfca;p=musl

diff --git a/src/thread/pthread_cancel.c b/src/thread/pthread_cancel.c
index c497dbe6..1b71aa42 100644
--- a/src/thread/pthread_cancel.c
+++ b/src/thread/pthread_cancel.c
@@ -1,7 +1,96 @@
 #include "pthread_impl.h"
+#include "syscall.h"
+#include "libc.h"
+
+long __cancel()
+{
+	pthread_t self = __pthread_self();
+	if (self->canceldisable == PTHREAD_CANCEL_ENABLE || self->cancelasync)
+		pthread_exit(PTHREAD_CANCELED);
+	self->canceldisable = PTHREAD_CANCEL_DISABLE;
+	return -ECANCELED;
+}
+
+/* If __syscall_cp_asm has adjusted the stack pointer, it must provide a
+ * definition of __cp_cancel to undo those adjustments and call __cancel.
+ * Otherwise, __cancel provides a definition for __cp_cancel. */
+
+weak_alias(__cancel, __cp_cancel);
+
+long __syscall_cp_asm(volatile void *, syscall_arg_t,
+                      syscall_arg_t, syscall_arg_t, syscall_arg_t,
+                      syscall_arg_t, syscall_arg_t, syscall_arg_t);
+
+long __syscall_cp_c(syscall_arg_t nr,
+                    syscall_arg_t u, syscall_arg_t v, syscall_arg_t w,
+                    syscall_arg_t x, syscall_arg_t y, syscall_arg_t z)
+{
+	pthread_t self;
+	long r;
+	int st;
+
+	if (!libc.has_thread_pointer || (st=(self=__pthread_self())->canceldisable)
+	    && (st==PTHREAD_CANCEL_DISABLE || nr==SYS_close))
+		return __syscall(nr, u, v, w, x, y, z);
+
+	r = __syscall_cp_asm(&self->cancel, nr, u, v, w, x, y, z);
+	if (r==-EINTR && nr!=SYS_close && self->cancel &&
+	    self->canceldisable != PTHREAD_CANCEL_DISABLE)
+		r = __cancel();
+	return r;
+}
+
+static void _sigaddset(sigset_t *set, int sig)
+{
+	unsigned s = sig-1;
+	set->__bits[s/8/sizeof *set->__bits] |= 1UL<<(s&8*sizeof *set->__bits-1);
+}
+
+static void cancel_handler(int sig, siginfo_t *si, void *ctx)
+{
+	pthread_t self = __pthread_self();
+	ucontext_t *uc = ctx;
+	const char *ip = ((char **)&uc->uc_mcontext)[CANCEL_REG_IP];
+	extern const char __cp_begin[1], __cp_end[1];
+
+	a_barrier();
+	if (!self->cancel || self->canceldisable == PTHREAD_CANCEL_DISABLE) return;
+
+	_sigaddset(&uc->uc_sigmask, SIGCANCEL);
+
+	if (self->cancelasync || ip >= __cp_begin && ip < __cp_end) {
+		((char **)&uc->uc_mcontext)[CANCEL_REG_IP] = (char *)__cp_cancel;
+		return;
+	}
+
+	__syscall(SYS_tkill, self->tid, SIGCANCEL);
+}
+
+void __testcancel()
+{
+	if (!libc.has_thread_pointer) return;
+	pthread_t self = __pthread_self();
+	if (self->cancel && !self->canceldisable)
+		__cancel();
+}
+
+static void init_cancellation()
+{
+	struct sigaction sa = {
+		.sa_flags = SA_SIGINFO | SA_RESTART,
+		.sa_sigaction = cancel_handler
+	};
+	sigfillset(&sa.sa_mask);
+	__libc_sigaction(SIGCANCEL, &sa, 0);
+}
 
 int pthread_cancel(pthread_t t)
 {
+	static int init;
+	if (!init) {
+		init_cancellation();
+		init = 1;
+	}
 	a_store(&t->cancel, 1);
 	return pthread_kill(t, SIGCANCEL);
 }