BigfootDev/flatbuffers
1
0
Fork 1
mirror of https://github.com/google/flatbuffers.git synced 2026-06-23 05:40:02 +00:00
Code Issues Packages Projects Releases Wiki Activity

Pulled out EndianSwap into its own function.

Browse Source 
Change-Id: I4a587102db8c435b739c92b6c464c94c4ea1fe42
This commit is contained in:
Wouter van Oortmerssen
2016-07-25 16:26:50 -07:00
parent 1bba4fd9ea
commit 2d427e0502
1 changed files with 31 additions and 29 deletions
Download Patch File Download Diff File Expand all files Collapse all files

60
include/flatbuffers/flatbuffers.h
View File

@@ -151,39 +151,41 @@ inline void EndianCheck() {
(void)endiantest; (void)endiantest;
} }
template<typename T> T EndianSwap(T t) {
#if defined(_MSC_VER)
#pragma push_macro("__builtin_bswap16")
#pragma push_macro("__builtin_bswap32")
#pragma push_macro("__builtin_bswap64")
#define __builtin_bswap16 _byteswap_ushort
#define __builtin_bswap32 _byteswap_ulong
#define __builtin_bswap64 _byteswap_uint64
#endif
if (sizeof(T) == 1) { // Compile-time if-then's.
return t;
} else if (sizeof(T) == 2) {
auto r = __builtin_bswap16(*reinterpret_cast<uint16_t *>(&t));
return *reinterpret_cast<T *>(&r);
} else if (sizeof(T) == 4) {
auto r = __builtin_bswap32(*reinterpret_cast<uint32_t *>(&t));
return *reinterpret_cast<T *>(&r);
} else if (sizeof(T) == 8) {
auto r = __builtin_bswap64(*reinterpret_cast<uint64_t *>(&t));
return *reinterpret_cast<T *>(&r);
} else {
assert(0);
}
#if defined(_MSC_VER)
#pragma pop_macro("__builtin_bswap16")
#pragma pop_macro("__builtin_bswap32")
#pragma pop_macro("__builtin_bswap64")
#endif
}
template<typename T> T EndianScalar(T t) { template<typename T> T EndianScalar(T t) {
#if FLATBUFFERS_LITTLEENDIAN #if FLATBUFFERS_LITTLEENDIAN
return t; return t;
#else #else
#if defined(_MSC_VER) return EndianSwap(t);
#pragma push_macro("__builtin_bswap16")
#pragma push_macro("__builtin_bswap32")
#pragma push_macro("__builtin_bswap64")
#define __builtin_bswap16 _byteswap_ushort
#define __builtin_bswap32 _byteswap_ulong
#define __builtin_bswap64 _byteswap_uint64
#endif
// If you're on the few remaining big endian platforms, we make the bold
// assumption you're also on gcc/clang, and thus have bswap intrinsics:
if (sizeof(T) == 1) { // Compile-time if-then's.
return t;
} else if (sizeof(T) == 2) {
auto r = __builtin_bswap16(*reinterpret_cast<uint16_t *>(&t));
return *reinterpret_cast<T *>(&r);
} else if (sizeof(T) == 4) {
auto r = __builtin_bswap32(*reinterpret_cast<uint32_t *>(&t));
return *reinterpret_cast<T *>(&r);
} else if (sizeof(T) == 8) {
auto r = __builtin_bswap64(*reinterpret_cast<uint64_t *>(&t));
return *reinterpret_cast<T *>(&r);
} else {
assert(0);
}
#if defined(_MSC_VER)
#pragma pop_macro("__builtin_bswap16")
#pragma pop_macro("__builtin_bswap32")
#pragma pop_macro("__builtin_bswap64")
#endif
#endif #endif
} }