libgit2/src/bswap.h
Ramsay Jones e2337f39c3 MSVC: Fix a syntax error caused by an inline function definition
Commit 5dddf7c (Add block-sha1 in favour of the mozilla routines
2010-04-14) introduced the "bswap.h" header file which contains
an inline function (default_swab32()).  The msvc compiler does
not support the inline keyword which causes the build to fail
with a syntax error.

However, msvc does support inline functions using the __inline
keyword language extension.  We already have the GIT_INLINE()
macro that allows us to hide this syntatic difference. In order
to fix the build, we simply use GIT_INLINE() in the definition
of the default_swab32() function.

Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
2010-04-28 20:55:04 +01:00

51 lines
1.0 KiB
C

/*
* Let's make sure we always have a sane definition for ntohl()/htonl().
* Some libraries define those as a function call, just to perform byte
* shifting, bringing significant overhead to what should be a simple
* operation.
*/
#include "common.h"
/*
* Default version that the compiler ought to optimize properly with
* constant values.
*/
GIT_INLINE(uint32_t) default_swab32(uint32_t val)
{
return (((val & 0xff000000) >> 24) |
((val & 0x00ff0000) >> 8) |
((val & 0x0000ff00) << 8) |
((val & 0x000000ff) << 24));
}
#undef bswap32
#if defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
#define bswap32(x) ({ \
uint32_t __res; \
if (__builtin_constant_p(x)) { \
__res = default_swab32(x); \
} else { \
__asm__("bswap %0" : "=r" (__res) : "0" ((uint32_t)(x))); \
} \
__res; })
#elif defined(_MSC_VER) && (defined(_M_IX86) || defined(_M_X64))
#include <stdlib.h>
#define bswap32(x) _byteswap_ulong(x)
#endif
#ifdef bswap32
#undef ntohl
#undef htonl
#define ntohl(x) bswap32(x)
#define htonl(x) bswap32(x)
#endif