view lib/portability.h @ 233:d4176f3f3835

Zap toys/Config.in and instead create generated/Config.in from contents of toys/*.c. Move relevant info into comment at the top of each toys/*.c. Also convert more of Makefile into a thin wrapper around shell scripts that actually do the work. (Makefile is only still there for the user interface.)
author Rob Landley <rob@landley.net>
date Sat, 19 Jan 2008 17:08:39 -0600
parents 5f1d3ad8a888
children 9051cb744d0a
line wrap: on
line source

// Humor glibc to get dprintf, then #define it to something more portable.
#define _GNU_SOURCE
#include <stdio.h>
#define fdprintf(...) dprintf(__VA_ARGS__)

#ifdef __GNUC__
#define noreturn	__attribute__((noreturn))
#else
#define noreturn
#endif

#ifndef __APPLE__
#include <byteswap.h>
#include <endian.h>

#if __BYTE_ORDER == __BIG_ENDIAN
#define IS_BIG_ENDIAN 1
#else
#define IS_BIG_ENDIAN 0
#endif

#else

#ifdef __BIG_ENDIAN__
#define IS_BIG_ENDIAN 1
#else
#define IS_BIG_ENDIAN 0
#endif

#endif

#if IS_BIG_ENDIAN
#define IS_LITTLE_ENDIAN 0
#define SWAP_BE16(x) (x)
#define SWAP_BE32(x) (x)
#define SWAP_BE64(x) (x)
#define SWAP_LE16(x) bswap_16(x)
#define SWAP_LE32(x) bswap_32(x)
#define SWAP_LE64(x) bswap_64(x)
#else
#define IS_LITTLE_ENDIAN 1
#define SWAP_BE16(x) bswap_16(x)
#define SWAP_BE32(x) bswap_32(x)
#define SWAP_BE64(x) bswap_64(x)
#define SWAP_LE16(x) (x)
#define SWAP_LE32(x) (x)
#define SWAP_LE64(x) (x)
#endif

// Some versions of gcc produce spurious "may be uninitialized" warnings in
// cases where it provably can't happen.  Unfortunately, although this warning
// is calculated and produced separately from the "is definitely used
// uninitialized" warnings, there's no way to turn off the broken spurious "may
// be" warnings without also turning off the non-broken "is" warnings.

#if CFG_TOYBOX_DEBUG
#define GCC_BUG =0
#else
#define GCC_BUG
#endif