From 347000929de775ae6b975a2959f5fabe81d6f1f0 Mon Sep 17 00:00:00 2001
From: Paul Tan <pyokagan@gmail.com>
Date: Sun, 2 Mar 2014 17:51:14 +0800
Subject: [PATCH] unix: workaround broken pthread_sigmask on Android

On android, if a call to `pthread_sigmask` fails with EINVAL, fallback
to `sigprocmask`. This workarounds the broken behaviour of
`pthread_sigmask` on Android versions < 4.1. See:

* https://android.googlesource.com/platform/bionic/+/9bf330b5
* https://code.google.com/p/android/issues/detail?id=15337

This is implemented by replacing all calls of `pthread_sigmask` to a new
function `uv__pthread_sigmask` which implements this fallback mechanism.
---
 include/pthread-fixes.h  | 13 +++++++++++++
 src/unix/pthread-fixes.c | 23 +++++++++++++++++++++++
 2 files changed, 36 insertions(+)

diff --git a/include/pthread-fixes.h b/include/pthread-fixes.h
index 230ce317..88c6b669 100644
--- a/include/pthread-fixes.h
+++ b/include/pthread-fixes.h
@@ -56,4 +56,17 @@ int pthread_barrier_destroy(pthread_barrier_t *barrier);
 #endif  /* defined(PTHREAD_BARRIER_SERIAL_THREAD) */
 
 int pthread_yield(void);
+
+/* Workaround pthread_sigmask() returning EINVAL on versions < 4.1 by
+ * replacing all calls to pthread_sigmask with sigprocmask. See:
+ * https://android.googlesource.com/platform/bionic/+/9bf330b5
+ * https://code.google.com/p/android/issues/detail?id=15337
+ */
+int uv__pthread_sigmask(int how, const sigset_t* set, sigset_t* oset);
+
+#ifdef pthread_sigmask
+#undef pthread_sigmask
+#endif
+#define pthread_sigmask(how, set, oldset) uv__pthread_sigmask(how, set, oldset)
+
 #endif  /* GOOGLE_BREAKPAD_COMMON_ANDROID_TESTING_PTHREAD_FIXES_H */
diff --git a/src/unix/pthread-fixes.c b/src/unix/pthread-fixes.c
index 2e4c542b..dc54f35d 100644
--- a/src/unix/pthread-fixes.c
+++ b/src/unix/pthread-fixes.c
@@ -29,6 +29,29 @@
    OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
 
+/* Android versions < 4.1 have a broken pthread_sigmask.
+ * Note that this block of code must come before any inclusion of
+ * pthread-fixes.h so that the real pthread_sigmask can be referenced.
+ * */
+#include <errno.h>
+#include <pthread.h>
+
+int uv__pthread_sigmask(int how, const sigset_t* set, sigset_t* oset) {
+  static int workaround;
+
+  if (workaround) {
+    return sigprocmask(how, set, oset);
+  } else if (pthread_sigmask(how, set, oset)) {
+    if (errno == EINVAL && sigprocmask(how, set, oset) == 0) {
+      workaround = 1;
+      return 0;
+    } else {
+      return -1;
+    }
+  } else {
+    return 0;
+  }
+}
 
 /*Android doesn't provide pthread_barrier_t for now.*/
 #ifndef PTHREAD_BARRIER_SERIAL_THREAD