1 files changed, 82 insertions, 0 deletions
diff --git a/src/runtime/cgo/gcc_sigaction.c b/src/runtime/cgo/gcc_sigaction.c
new file mode 100644
index 0000000..fcf1e50
--- /dev/null
+++ b/src/runtime/cgo/gcc_sigaction.c
@@ -0,0 +1,82 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build linux,amd64 linux,arm64 linux,ppc64le
+
+#include <errno.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <string.h>
+#include <signal.h>
+
+#include "libcgo.h"
+
+// go_sigaction_t is a C version of the sigactiont struct from
+// defs_linux_amd64.go.  This definition — and its conversion to and from struct
+// sigaction — are specific to linux/amd64.
+typedef struct {
+	uintptr_t handler;
+	uint64_t flags;
+	uintptr_t restorer;
+	uint64_t mask;
+} go_sigaction_t;
+
+// SA_RESTORER is part of the kernel interface.
+// This is Linux i386/amd64 specific.
+#ifndef SA_RESTORER
+#define SA_RESTORER 0x4000000
+#endif
+
+int32_t
+x_cgo_sigaction(intptr_t signum, const go_sigaction_t *goact, go_sigaction_t *oldgoact) {
+	int32_t ret;
+	struct sigaction act;
+	struct sigaction oldact;
+	size_t i;
+
+	_cgo_tsan_acquire();
+
+	memset(&act, 0, sizeof act);
+	memset(&oldact, 0, sizeof oldact);
+
+	if (goact) {
+		if (goact->flags & SA_SIGINFO) {
+			act.sa_sigaction = (void(*)(int, siginfo_t*, void*))(goact->handler);
+		} else {
+			act.sa_handler = (void(*)(int))(goact->handler);
+		}
+		sigemptyset(&act.sa_mask);
+		for (i = 0; i < 8 * sizeof(goact->mask); i++) {
+			if (goact->mask & ((uint64_t)(1)<<i)) {
+				sigaddset(&act.sa_mask, (int)(i+1));
+			}
+		}
+		act.sa_flags = (int)(goact->flags & ~(uint64_t)SA_RESTORER);
+	}
+
+	ret = sigaction((int)signum, goact ? &act : NULL, oldgoact ? &oldact : NULL);
+	if (ret == -1) {
+		// runtime.rt_sigaction expects _cgo_sigaction to return errno on error.
+		_cgo_tsan_release();
+		return errno;
+	}
+
+	if (oldgoact) {
+		if (oldact.sa_flags & SA_SIGINFO) {
+			oldgoact->handler = (uintptr_t)(oldact.sa_sigaction);
+		} else {
+			oldgoact->handler = (uintptr_t)(oldact.sa_handler);
+		}
+		oldgoact->mask = 0;
+		for (i = 0; i < 8 * sizeof(oldgoact->mask); i++) {
+			if (sigismember(&oldact.sa_mask, (int)(i+1)) == 1) {
+				oldgoact->mask |= (uint64_t)(1)<<i;
+			}
+		}
+		oldgoact->flags = (uint64_t)oldact.sa_flags;
+	}
+
+	_cgo_tsan_release();
+	return ret;
+}