From: Dagobert Michelsen Date: Wed, 21 Mar 2018 21:09:15 +0000 (+0100) Subject: Add fallback for endianess conversion X-Git-Url: https://git.verplant.org/?a=commitdiff_plain;h=32f1126d3f18fce78e6d06c8c7f94763f21afcef;p=collectd.git Add fallback for endianess conversion --- diff --git a/src/stdendian.h b/src/stdendian.h new file mode 100644 index 00000000..d4190968 --- /dev/null +++ b/src/stdendian.h @@ -0,0 +1,242 @@ +/* + * stdendian.h + * + * This header defines the following endian macros as defined here: + * http://austingroupbugs.net/view.php?id=162 + * + * BYTE_ORDER this macro shall have a value equal to one + * of the *_ENDIAN macros in this header. + * LITTLE_ENDIAN if BYTE_ORDER == LITTLE_ENDIAN, the host + * byte order is from least significant to + * most significant. + * BIG_ENDIAN if BYTE_ORDER == BIG_ENDIAN, the host byte + * order is from most significant to least + * significant. + * + * The following are defined as macros: + * + * uint16_t bswap16(uint16_t x); + * uint32_t bswap32(uint32_t x); + * uint64_t bswap64(uint64_t x); + + * uint16_t htobe16(uint16_t x); + * uint16_t htole16(uint16_t x); + * uint16_t be16toh(uint16_t x); + * uint16_t le16toh(uint16_t x); + * + * uint32_t htobe32(uint32_t x); + * uint32_t htole32(uint32_t x); + * uint32_t be32toh(uint32_t x); + * uint32_t le32toh(uint32_t x); + * + * uint64_t htobe64(uint64_t x); + * uint64_t htole64(uint64_t x); + * uint64_t be64toh(uint64_t x); + * uint64_t le64toh(uint64_t x); + * + * The header defines the following macro for OpenCL compatibility + * https://www.khronos.org/registry/cl/sdk/2.0/docs/man/xhtml/preprocessorDirectives.html + * + * __ENDIAN_LITTLE__ if BYTE_ORDER == LITTLE_ENDIAN then this + * macro is present for OpenCL compatibility + * + * The implementation provides a uniform interface to endian macros using only + * system headers on recent Linux, Darwin, FreeBSD, Solaris and Windows systems. + * + * This approach is intended to avoid the need for preflight configure scripts. + * An alternative approach would be to test compiler CPU architecture marcros. + * + * This header has had *limited* testing on recent C11/C++11 compilers and is + * based on the austin bug tracker interface, manpages, and headers present in + * Linux, FreeBSD, Windows, Solaris and Darwin. + * + * The header uses __builtin_bswapXX intrinsic with GCC/Clang (__GNUC__) on + * platforms that do not provide bswap16, bswap32, bswap64 (Darwin) + * + * Public Domain. + */ + +#if HAVE_STDINT_H +#include +#endif + +/* Linux / GLIBC */ +#if defined(__linux__) || defined(__GLIBC__) +#include +#include +#define __ENDIAN_DEFINED 1 +#define __BSWAP_DEFINED 1 +#define __HOSTSWAP_DEFINED 1 +#define _BYTE_ORDER __BYTE_ORDER +#define _LITTLE_ENDIAN __LITTLE_ENDIAN +#define _BIG_ENDIAN __BIG_ENDIAN +#define bswap16(x) bswap_16(x) +#define bswap32(x) bswap_32(x) +#define bswap64(x) bswap_64(x) +#endif /* __linux__ || __GLIBC__ */ + +/* BSD */ +#if defined(__FreeBSD__) || defined(__NetBSD__) || \ + defined(__DragonFly__) || defined(__OpenBSD__) +#include +#define __ENDIAN_DEFINED 1 +#define __BSWAP_DEFINED 1 +#define __HOSTSWAP_DEFINED 1 +#endif /* BSD */ + +/* Solaris */ +#if defined (sun) +#include +#include +#define bswap16(x) BSWAP_16(x) +#define bswap32(x) BSWAP_32(x) +#define bswap64(x) BSWAP_64(x) +/* sun headers don't set a value for _LITTLE_ENDIAN or _BIG_ENDIAN */ +#if defined(_LITTLE_ENDIAN) +#undef _LITTLE_ENDIAN +#define _LITTLE_ENDIAN 1234 +#define _BIG_ENDIAN 4321 +#define _BYTE_ORDER _LITTLE_ENDIAN +#elif defined(_BIG_ENDIAN) +#undef _BIG_ENDIAN +#define _LITTLE_ENDIAN 1234 +#define _BIG_ENDIAN 4321 +#define _BYTE_ORDER _BIG_ENDIAN +#endif +#define __ENDIAN_DEFINED 1 +#endif /* sun */ + +/* Windows */ +#if defined(_WIN32) || defined(_MSC_VER) +/* assumes all Microsoft targets are little endian */ +#define _LITTLE_ENDIAN 1234 +#define _BIG_ENDIAN 4321 +#define _BYTE_ORDER _LITTLE_ENDIAN +#define __ENDIAN_DEFINED 1 +#endif /* _MSC_VER */ + +/* OS X */ +#if defined(__APPLE__) +#include +#define _BYTE_ORDER BYTE_ORDER +#define _LITTLE_ENDIAN LITTLE_ENDIAN +#define _BIG_ENDIAN BIG_ENDIAN +#define __ENDIAN_DEFINED 1 +#endif /* __APPLE__ */ + +/* OpenCL */ +#if defined (__OPENCL_VERSION__) +#define _LITTLE_ENDIAN 1234 +#define __BIG_ENDIAN 4321 +#if defined (__ENDIAN_LITTLE__) +#define _BYTE_ORDER _LITTLE_ENDIAN +#else +#define _BYTE_ORDER _BIG_ENDIAN +#endif +#define bswap16(x) as_ushort(as_uchar2(ushort(x)).s1s0) +#define bswap32(x) as_uint(as_uchar4(uint(x)).s3s2s1s0) +#define bswap64(x) as_ulong(as_uchar8(ulong(x)).s7s6s5s4s3s2s1s0) +#define __ENDIAN_DEFINED 1 +#define __BSWAP_DEFINED 1 +#endif + +/* Unknown */ +#if !__ENDIAN_DEFINED +#error Could not determine CPU byte order +#endif + +/* POSIX - http://austingroupbugs.net/view.php?id=162 */ +#ifndef BYTE_ORDER +#define BYTE_ORDER _BYTE_ORDER +#endif +#ifndef LITTLE_ENDIAN +#define LITTLE_ENDIAN _LITTLE_ENDIAN +#endif +#ifndef BIG_ENDIAN +#define BIG_ENDIAN _BIG_ENDIAN +#endif + +/* OpenCL compatibility - define __ENDIAN_LITTLE__ on little endian systems */ +#if _BYTE_ORDER == _LITTLE_ENDIAN +#if !defined (__ENDIAN_LITTLE__) +#define __ENDIAN_LITTLE__ 1 +#endif +#endif + +/* Byte swap macros */ +#if !__BSWAP_DEFINED + +#ifndef bswap16 +/* handle missing __builtin_bswap16 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=52624 */ +#if defined __GNUC__ +/* define bswap16(x) __builtin_bswap16(x) */ +#else +#define bswap16(x) ((uint16_t)((((uint16_t) (x) & 0xff00) >> 8) | \ + (((uint16_t) (x) & 0x00ff) << 8))) +#endif +#endif + +#ifndef bswap32 +#if defined __GNUC__ +#define bswap32(x) __builtin_bswap32(x) +#else +#define bswap32(x) ((uint32_t)((((uint32_t) (x) & 0xff000000) >> 24) | \ + (((uint32_t) (x) & 0x00ff0000) >> 8) | \ + (((uint32_t) (x) & 0x0000ff00) << 8) | \ + (((uint32_t) (x) & 0x000000ff) << 24))) +#endif +#endif + +#ifndef bswap64 +#if defined __GNUC__ +#define bswap64(x) __builtin_bswap64(x) +#else +#define bswap64(x) ((uint64_t)((((uint64_t) (x) & 0xff00000000000000ull) >> 56) | \ + (((uint64_t) (x) & 0x00ff000000000000ull) >> 40) | \ + (((uint64_t) (x) & 0x0000ff0000000000ull) >> 24) | \ + (((uint64_t) (x) & 0x000000ff00000000ull) >> 8) | \ + (((uint64_t) (x) & 0x00000000ff000000ull) << 8) | \ + (((uint64_t) (x) & 0x0000000000ff0000ull) << 24) | \ + (((uint64_t) (x) & 0x000000000000ff00ull) << 40) | \ + (((uint64_t) (x) & 0x00000000000000ffull) << 56))) +#endif +#endif + +#endif + +/* Host swap macros */ +#ifndef __HOSTSWAP_DEFINED +#if __BYTE_ORDER == __LITTLE_ENDIAN +#define htobe16(x) bswap16((x)) +#define htole16(x) ((uint16_t)(x)) +#define be16toh(x) bswap16((x)) +#define le16toh(x) ((uint16_t)(x)) + +#define htobe32(x) bswap32((x)) +#define htole32(x) ((uint32_t)(x)) +#define be32toh(x) bswap32((x)) +#define le32toh(x) ((uint32_t)(x)) + +#define htobe64(x) bswap64((x)) +#define htole64(x) ((uint64_t)(x)) +#define be64toh(x) bswap64((x)) +#define le64toh(x) ((uint64_t)(x)) +#elif __BYTE_ORDER == __BIG_ENDIAN +#define htobe16(x) ((uint16_t)(x)) +#define htole16(x) bswap16((x)) +#define be16toh(x) ((uint16_t)(x)) +#define le16toh(x) bswap16((x)) + +#define htobe32(x) ((uint32_t)(x)) +#define htole32(x) bswap32((x)) +#define be32toh(x) ((uint32_t)(x)) +#define le64toh(x) bswap64((x)) + +#define htobe64(x) ((uint64_t)(x)) +#define htole64(x) bswap64((x)) +#define be64toh(x) ((uint64_t)(x)) +#define le32toh(x) bswap32((x)) +#endif +#endif + +