1
0
Fork 0
mirror of https://github.com/ruby/ruby.git synced 2022-11-09 12:17:21 -05:00
ruby--ruby/include/ruby/3/dosish.h
卜部昌平 4ff3f20540 add #include guard hack
According to MSVC manual (*1), cl.exe can skip including a header file
when that:

- contains #pragma once, or
- starts with #ifndef, or
- starts with #if ! defined.

GCC has a similar trick (*2), but it acts more stricter (e. g. there
must be _no tokens_ outside of #ifndef...#endif).

Sun C lacked #pragma once for a looong time.  Oracle Developer Studio
12.5 finally implemented it, but we cannot assume such recent version.

This changeset modifies header files so that each of them include
strictly one #ifndef...#endif.  I believe this is the most portable way
to trigger compiler optimizations. [Bug #16770]

*1: https://docs.microsoft.com/en-us/cpp/preprocessor/once
*2: https://gcc.gnu.org/onlinedocs/cppinternals/Guard-Macros.html
2020-04-13 16:06:00 +09:00

63 lines
2 KiB
C++

#ifndef RUBY3_DOSISH_H /*-*-C++-*-vi:se ft=cpp:*/
#define RUBY3_DOSISH_H
/**
* @file
* @author Ruby developers <ruby-core@ruby-lang.org>
* @copyright This file is a part of the programming language Ruby.
* Permission is hereby granted, to either redistribute and/or
* modify this file, provided that the conditions mentioned in the
* file COPYING are met. Consult the file for details.
* @warning Symbols prefixed with either `RUBY3` or `ruby3` are
* implementation details. Don't take them as canon. They could
* rapidly appear then vanish. The name (path) of this header file
* is also an implementation detail. Do not expect it to persist
* at the place it is now. Developers are free to move it anywhere
* anytime at will.
* @note To ruby-core: remember that this header can be possibly
* recursively included from extension libraries written in C++.
* Do not expect for instance `__VA_ARGS__` is always available.
* We assume C99 for ruby itself but we don't assume languages of
* extension libraries. They could be written in C++98.
* @brief Support for so-called dosish systems.
*/
#ifdef __CYGWIN__
#undef _WIN32
#endif
#if defined(_WIN32)
/*
DOSISH mean MS-Windows style filesystem.
But you should use more precise macros like DOSISH_DRIVE_LETTER, PATH_SEP,
ENV_IGNORECASE or CASEFOLD_FILESYSTEM.
*/
#define DOSISH 1
# define DOSISH_DRIVE_LETTER
#endif
#ifdef _WIN32
#include "ruby/win32.h"
#endif
#if defined(DOSISH)
#define PATH_SEP ";"
#else
#define PATH_SEP ":"
#endif
#define PATH_SEP_CHAR PATH_SEP[0]
#define PATH_ENV "PATH"
#if defined(DOSISH)
#define ENV_IGNORECASE
#endif
#ifndef CASEFOLD_FILESYSTEM
# if defined DOSISH
# define CASEFOLD_FILESYSTEM 1
# else
# define CASEFOLD_FILESYSTEM 0
# endif
#endif
#endif /* RUBY3_DOSISH_H */