am 1bc7d0c8: am 70c958c4: Merge "Save/restore errno in SIGCHLD handler." into mnc-dr-dev
* commit '1bc7d0c84a1fbd27add883b8e000096677a1ca22':
Save/restore errno in SIGCHLD handler.
diff --git a/core/jni/com_android_internal_os_Zygote.cpp b/core/jni/com_android_internal_os_Zygote.cpp
index 4c920dc..b431a3f 100644
--- a/core/jni/com_android_internal_os_Zygote.cpp
+++ b/core/jni/com_android_internal_os_Zygote.cpp
@@ -83,6 +83,14 @@
pid_t pid;
int status;
+ // It's necessary to save and restore the errno during this function.
+ // Since errno is stored per thread, changing it here modifies the errno
+ // on the thread on which this signal handler executes. If a signal occurs
+ // between a call and an errno check, it's possible to get the errno set
+ // here.
+ // See b/23572286 for extra information.
+ int saved_errno = errno;
+
while ((pid = waitpid(-1, &status, WNOHANG)) > 0) {
// Log process-death status that we care about. In general it is
// not safe to call LOG(...) from a signal handler because of
@@ -118,6 +126,8 @@
if (pid < 0 && errno != ECHILD) {
ALOGW("Zygote SIGCHLD error in waitpid: %s", strerror(errno));
}
+
+ errno = saved_errno;
}
// Configures the SIGCHLD handler for the zygote process. This is configured