[libc] Add implementation of pthread_atfork.

Reviewed By: michaelrj

Differential Revision: https://reviews.llvm.org/D135432

1 files changed, 25 insertions, 0 deletions

diff --git a/libc/src/pthread/pthread_atfork.cpp b/libc/src/pthread/pthread_atfork.cpp
new file mode 100644
index 000000000000..bff80d5fd456
--- /dev/null
+++ b/libc/src/pthread/pthread_atfork.cpp
@@ -0,0 +1,25 @@
+//===-- Linux implementation of the pthread_atfork function ---------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "pthread_atfork.h"
+
+#include "src/__support/common.h"
+#include "src/__support/fork_callbacks.h"
+
+#include <errno.h>
+#include <pthread.h> // For pthread_* type definitions.
+
+namespace __llvm_libc {
+
+LLVM_LIBC_FUNCTION(int, pthread_atfork,
+                   (__atfork_callback_t prepare, __atfork_callback_t parent,
+                    __atfork_callback_t child)) {
+  return register_atfork_callbacks(prepare, parent, child) ? 0 : ENOMEM;
+}
+
+} // namespace __llvm_libc