X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;ds=sidebyside;f=src%2Fthread%2Fpthread_mutexattr_setprotocol.c;h=511cc32d8f0ad9df99d4193901dbb514160f928e;hb=d28cd0ad428d63c186003fdf9c02470561650a04;hp=c92a31c8a46cf98238560a8b79f3041f137128ba;hpb=19b1a8453e9d329a16711900a84797c5f1333208;p=musl

diff --git a/src/thread/pthread_mutexattr_setprotocol.c b/src/thread/pthread_mutexattr_setprotocol.c
index c92a31c8..511cc32d 100644
--- a/src/thread/pthread_mutexattr_setprotocol.c
+++ b/src/thread/pthread_mutexattr_setprotocol.c
@@ -1,7 +1,29 @@
 #include "pthread_impl.h"
+#include "syscall.h"
+
+static pthread_once_t check_pi_once;
+static int check_pi_result;
+
+static void check_pi()
+{
+	volatile int lk = 0;
+	check_pi_result = -__syscall(SYS_futex, &lk, FUTEX_LOCK_PI, 0, 0);
+}
 
 int pthread_mutexattr_setprotocol(pthread_mutexattr_t *a, int protocol)
 {
-	if (protocol) return ENOTSUP;
-	return 0;
+	switch (protocol) {
+	case PTHREAD_PRIO_NONE:
+		a->__attr &= ~8;
+		return 0;
+	case PTHREAD_PRIO_INHERIT:
+		pthread_once(&check_pi_once, check_pi);
+		if (check_pi_result) return check_pi_result;
+		a->__attr |= 8;
+		return 0;
+	case PTHREAD_PRIO_PROTECT:
+		return ENOTSUP;
+	default:
+		return EINVAL;
+	}
 }