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Diffstat (limited to 'features.h')
| -rw-r--r-- | features.h | 157 |
1 files changed, 157 insertions, 0 deletions
diff --git a/features.h b/features.h new file mode 100644 index 0000000000..0778092ed9 --- /dev/null +++ b/features.h @@ -0,0 +1,157 @@ +/* Copyright (C) 1991, 1992, 1993 Free Software Foundation, Inc. +This file is part of the GNU C Library. + +The GNU C Library is free software; you can redistribute it and/or +modify it under the terms of the GNU Library General Public License as +published by the Free Software Foundation; either version 2 of the +License, or (at your option) any later version. + +The GNU C Library is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +Library General Public License for more details. + +You should have received a copy of the GNU Library General Public +License along with the GNU C Library; see the file COPYING.LIB. If +not, write to the Free Software Foundation, Inc., 675 Mass Ave, +Cambridge, MA 02139, USA. */ + +#ifndef _FEATURES_H + +#define _FEATURES_H 1 + +/* These are defined by the user (or the compiler) + to specify the desired environment: + + __STRICT_ANSI__ ANSI Standard C. + _POSIX_SOURCE IEEE Std 1003.1. + _POSIX_C_SOURCE If ==1, like _POSIX_SOURCE; if ==2 add IEEE Std 1003.2. + _BSD_SOURCE ANSI, POSIX, and 4.3BSD things. + _SVID_SOURCE ANSI, POSIX, and SVID things. + _GNU_SOURCE All of the above, plus GNU extensions. + + The `-ansi' switch to the GNU C compiler defines __STRICT_ANSI__. + If none of these are defined, the default is _GNU_SOURCE. + If more than one of these are defined, they accumulate. + For example __STRICT_ANSI__, _POSIX_SOURCE and _POSIX_C_SOURCE + together give you ANSI C, 1003.1, and 1003.2, but nothing else. + + These are defined by this file and are used by the + header files to decide what to declare or define: + + __USE_POSIX Define IEEE Std 1003.1 things. + __USE_POSIX2 Define IEEE Std 1003.2 things. + __USE_BSD Define 4.3BSD things. + __USE_SVID Define SVID things. + __USE_MISC Define things common to BSD and System V Unix. + __USE_GNU Define GNU extensions. + __FAVOR_BSD Favor 4.3BSD things in cases of conflict. + + The macro `__GNU_LIBRARY__' is defined by this file unconditionally. + + All macros defined by this file are defined as 1. + All macros listed above as possibly being defined by this file are + explicitly undefined if they are not explicitly defined. + Feature-test macros that are not defined by the user or compiler + but are implied by the other feature-test macros defined (or by the + lack of any definitions) are defined by the file. */ + + +/* Undefine everything, so we get a clean slate. */ +#undef __USE_POSIX +#undef __USE_POSIX2 +#undef __USE_BSD +#undef __USE_SVID +#undef __USE_MISC +#undef __USE_GNU +#undef __FAVOR_BSD + + +/* If nothing is defined, define _GNU_SOURCE. */ +#if (!defined(_GNU_SOURCE) && !defined(__STRICT_ANSI__) && \ + !defined(_POSIX_SOURCE) && !defined(_POSIX_C_SOURCE) && \ + !defined(_BSD_SOURCE) && !defined(_SVID_SOURCE)) +#define _GNU_SOURCE 1 +#endif + + +/* Always use ANSI things. */ +#define __USE_ANSI 1 + + +/* If _BSD_SOURCE was defined by the user, favor BSD over POSIX. */ +#ifdef _BSD_SOURCE +#define __FAVOR_BSD 1 +#endif + + +/* If nothing (other than _GNU_SOURCE) is defined, + define _BSD_SOURCE and _SVID_SOURCE. */ +#if (!defined(__STRICT_ANSI__) && !defined(_POSIX_SOURCE) && \ + !defined(_POSIX_C_SOURCE) && !defined(_BSD_SOURCE) && \ + !defined(_SVID_SOURCE)) +#define _BSD_SOURCE 1 +#define _SVID_SOURCE 1 +#endif + +/* If none of the ANSI/POSIX macros are defined, use POSIX.1 and POSIX.2. */ +#if (!defined(__STRICT_ANSI__) && !defined(_POSIX_SOURCE) && \ + !defined(_POSIX_C_SOURCE)) +#define _POSIX_SOURCE 1 +#define _POSIX_C_SOURCE 2 +#endif + +#if defined(_POSIX_SOURCE) || _POSIX_C_SOURCE >= 1 +#define __USE_POSIX 1 +#endif + +#if defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE >= 2 +#define __USE_POSIX2 1 +#endif + +#if defined(_BSD_SOURCE) || defined(_SVID_SOURCE) +#define __USE_MISC 1 +#endif + +#ifdef _BSD_SOURCE +#define __USE_BSD 1 +#endif + +#ifdef _SVID_SOURCE +#define __USE_SVID 1 +#endif + +#ifdef _GNU_SOURCE +#define __USE_GNU 1 +#endif + + +#undef __GNU_LIBRARY__ +#define __GNU_LIBRARY__ 1 + + +#if !defined(__GNUC__) || __GNUC__ < 2 +/* In GCC version 2, (__extension__ EXPR) will not complain + about GCC extensions used in EXPR under -ansi or -pedantic. */ +#define __extension__ +#endif + + +/* This is here only because every header file already includes this one. */ +#include <sys/cdefs.h> + +/* This is here only because every header file already includes this one. */ +#ifndef _LIBC +/* Get the definitions of all the appropriate `__stub_FUNCTION' symbols. + <stubs.h> contains `#define __stub_FUNCTION' when FUNCTION is a stub + which will always return failure (and set errno to ENOSYS). + + We avoid including <stubs.h> when compiling the C library itself to + avoid a dependency loop. stubs.h depends on every object file. If + this #include were done for the library source code, then every object + file would depend on stubs.h. */ + +#include <stubs.h> +#endif + +#endif /* __features.h */ |