[Sanitizers] Consolidate internal errno definitions.

Move internal errno definitions to common to be shared by all sanitizers
and to be used by allocators.

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@307233 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 35 insertions, 0 deletions

diff --git a/lib/sanitizer_common/sanitizer_errno.h b/lib/sanitizer_common/sanitizer_errno.h
new file mode 100644
index 000000000..c405307ba
--- /dev/null
+++ b/lib/sanitizer_common/sanitizer_errno.h
@@ -0,0 +1,35 @@
+//===-- sanitizer_errno.h ---------------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file is shared between sanitizers run-time libraries.
+//
+// Defines errno to avoid including errno.h and its dependencies into sensitive
+// files (e.g. interceptors are not supposed to include any system headers).
+// It's ok to use errno.h directly when your file already depend on other system
+// includes though.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef SANITIZER_ERRNO_H
+#define SANITIZER_ERRNO_H
+
+#include "sanitizer_errno_codes.h"
+#include "sanitizer_platform.h"
+
+#if SANITIZER_FREEBSD || SANITIZER_MAC
+#  define __errno_location __error
+#elif SANITIZER_ANDROID
+#  define __errno_location __errno
+#endif
+
+extern "C" int *__errno_location();
+
+#define errno (*__errno_location())
+
+#endif  // SANITIZER_ERRNO_H