From: Rich Felker <dalias@aerifal.cx>
Date: Mon, 8 Apr 2013 03:19:00 +0000 (-0400)
Subject: fix signalfd not to ignore flags
X-Git-Url: http://nsz.repo.hu/git/?p=musl;a=commitdiff_plain;h=bcd9302508e5b89cfdcf2a2acebdf05d88d7479e

fix signalfd not to ignore flags

also include fallback code for broken kernels that don't support the
flags. as usual, the fallback has a race condition that can leak file
descriptors.
---

diff --git a/src/linux/signalfd.c b/src/linux/signalfd.c
index 94de3627..da6bcedb 100644
--- a/src/linux/signalfd.c
+++ b/src/linux/signalfd.c
@@ -1,8 +1,19 @@
 #include <sys/signalfd.h>
 #include <signal.h>
+#include <errno.h>
+#include <fcntl.h>
 #include "syscall.h"
 
 int signalfd(int fd, const sigset_t *sigs, int flags)
 {
-	return syscall(SYS_signalfd, fd, sigs, _NSIG/8);
+	int ret = __syscall(SYS_signalfd4, fd, sigs, _NSIG/8, flags);
+	if (ret != -ENOSYS) return __syscall_ret(ret);
+	ret = __syscall(SYS_signalfd, fd, sigs, _NSIG/8);
+	if (ret >= 0) {
+		if (flags & SFD_CLOEXEC)
+			__syscall(SYS_fcntl, ret, F_SETFD, FD_CLOEXEC);
+		if (flags & SFD_NONBLOCK)
+			__syscall(SYS_fcntl, ret, F_SETFL, O_NONBLOCK);
+	}
+	return __syscall_ret(ret);
 }