thodg/libgit2/src/bswap.h

• Show log

  Commit

• Hash : e2337f39
  Author :
  Date : 2010-04-25T21:55:41
  

  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>

Download

• src/bswap.h

• /*
   * 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
  

Download