Introduce OS_NACL_SFI and OS_NACL_NONSFI macros.

build/build_config.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // This file adds defines about the platform we're currently building on.
 //  Operating System:
-//    OS_WIN / OS_MACOSX / OS_LINUX / OS_POSIX (MACOSX or LINUX) / OS_NACL
+//    OS_WIN / OS_MACOSX / OS_LINUX / OS_POSIX (MACOSX or LINUX) /
+//    OS_NACL (NACL_SFI or NACL_NONSFI) / OS_NACL_SFI / OS_NACL_NONSFI
 //  Compiler:
 //    COMPILER_MSVC / COMPILER_GCC
 //  Processor:
 //    ARCH_CPU_X86 / ARCH_CPU_X86_64 / ARCH_CPU_X86_FAMILY (X86 or X86_64)
 //    ARCH_CPU_32_BITS / ARCH_CPU_64_BITS
 
 #ifndef BUILD_BUILD_CONFIG_H_
 #define BUILD_BUILD_CONFIG_H_
 
 // A set of macros to use for platform detection.
 #if defined(__native_client__)
 // __native_client__ must be first, so that other OS_ defines are not set.
 #define OS_NACL 1
+// In __native_client__ build, we also define one more macro depends on the
+// build is for Non-SFI binary or SFI binary.

[Junichi Uekawa, 2014/10/27 12:14:08]

This file is read by many people when they port things.
When a reader reads this document, I would expect to be able to distinguish what
they are.
Since it's something that we've defined as opposed to someone else, it might be
our duty to try to explain it succinctly.

ala "OS_NACL comes in two sandboxing technology flavors, SFI or Non-SFI. See XXX
for details."

[hidehiko, 2014/10/27 13:11:53]

Indeed. Updated the comment.

+#if defined(__native_client_nonsfi__)
+#define OS_NACL_NONSFI
+#else
+#define OS_NACL_SFI
+#endif
 #elif defined(ANDROID)
 #define OS_ANDROID 1
 #elif defined(__APPLE__)
 // only include TargetConditions after testing ANDROID as some android builds
 // on mac don't have this header available and it's not needed unless the target
 // is really mac/ios.
 #include <TargetConditionals.h>
 #define OS_MACOSX 1
 #if defined(TARGET_OS_IPHONE) && TARGET_OS_IPHONE
 #define OS_IOS 1
@@ skipping 119 matching lines @@
 #if defined(OS_ANDROID)
 // The compiler thinks std::string::const_iterator and "const char*" are
 // equivalent types.
 #define STD_STRING_ITERATOR_IS_CHAR_POINTER
 // The compiler thinks base::string16::const_iterator and "char16*" are
 // equivalent types.
 #define BASE_STRING16_ITERATOR_IS_CHAR16_POINTER
 #endif
 
 #endif  // BUILD_BUILD_CONFIG_H_