types.h

#ifndef _TYPES_H
#define _TYPES_H
/* include this file AFTER you have included libc files, since some libc's defines these, and get confused if predefined */

#ifdef HAVE_INTTYPES_H
#include <inttypes.h>
#endif

#ifdef HAVE_STDINT_H
#include <stdint.h>
#endif

#ifdef HAVE_SYS_CDEFS_H
#include <sys/cdefs.h>
#endif

#ifdef HAVE_BYTESWAP_H
#include <byteswap.h>
#else
#define __bswap_16(x) \
     ((((x) >> 8) & 0xff) | (((x) & 0xff) << 8))
#define __bswap_32(x) \
     ((((x) & 0xff000000) >> 24) | (((x) & 0x00ff0000) >>  8) |               \
      (((x) & 0x0000ff00) <<  8) | (((x) & 0x000000ff) << 24))
#define __bswap_64(x) \
     ((((x) & 0xff00000000000000ull) >> 56)                                   \
      | (((x) & 0x00ff000000000000ull) >> 40)                                 \
      | (((x) & 0x0000ff0000000000ull) >> 24)                                 \
      | (((x) & 0x000000ff00000000ull) >> 8)                                  \
      | (((x) & 0x00000000ff000000ull) << 8)                                  \
      | (((x) & 0x0000000000ff0000ull) << 24)                                 \
      | (((x) & 0x000000000000ff00ull) << 40)                                 \
      | (((x) & 0x00000000000000ffull) << 56))
#endif

#ifdef WORDS_BIGENDIAN
#   define int16_little(x)   ((int16_t)(__bswap_16 (x)))
#   define int32_little(x)   ((int32_t)(__bswap_32 (x)))
#   define uint16_little(x)  ((uint16_t)(__bswap_16 (x)))
#   define uint32_little(x)  ((uint32_t)(__bswap_32 (x)))
#   define uint64_little(x)  ((uint16_t)(__bswap_64 (x)))
#   define int16_big(x)      (x)
#   define int32_big(x)      (x)
#   define uint16_big(x)     (x)
#   define uint32_big(x)     (x)
#   define uint64_big(x)     (x)
# else
#   define int16_little(x)   (x)
#   define int32_little(x)   (x)
#   define uint16_little(x)  (x)
#   define uint32_little(x)  (x)
#   define uint64_little(x)  (x)
#   define int16_big(x)      ((int16_t)(__bswap_16 (x)))
#   define int32_big(x)      ((int32_t)(__bswap_32 (x)))
#   define uint16_big(x)     ((uint16_t)(__bswap_16 (x)))
#   define uint32_big(x)     ((uint32_t)(__bswap_32 (x)))
#   define uint64_big(x)     ((uint64_t)(__bswap_64 (x)))
# endif

/* oddly this is declared in a glibc header, so not all GCC have it. */
#ifdef __GNUC__
# ifndef __GNUC_PREREQ
#  define __GNUC_PREREQ(ma, mi)   \
          (__GNUC__ > (ma) || __GNUC__ == (ma) && __GNUC_MINOR__ >= (mi))
# endif
#endif

/* Detect MacOS / OS-X */
#if defined(__APPLE__) && defined(__MACH__)
# ifdef HAVE_AVAILABILITY_H
#  include <Availability.h>
# endif
# ifdef HAVE_AVAILABILITYVERSIONS_H
/* This header file is available from MacOS version 10.15 */
#  include <AvailabilityVersions.h>
# endif
# ifdef HAVE_AVAILABILITYMACROS_H
#  include <AvailabilityMacros.h>
# endif
# if !defined(MAC_OS_X_VERSION_10_12) || MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_12
# include <time.h>
# include <mach/clock_types.h>
#  define CLOCK_REALTIME CALENDAR_CLOCK
#  define CLOCK_MONOTONIC SYSTEM_CLOCK

#  ifdef __cplusplus
extern "C" {
#  endif

typedef int clockid_t;
int clock_gettime(clockid_t clk_id, struct timespec *tp);

#  ifdef __cplusplus
}
#  endif

# endif
#endif

# ifdef __HAIKU__
#  ifdef ioctl
#   undef ioctl
#  endif
# endif

#ifdef _WIN32
# define localtime_r(a,b) (localtime_s(b,a)?0:b)
#endif

#ifdef _WIN32
#define OCP_INTERNAL
#else
#define OCP_INTERNAL __attribute__ ((visibility ("internal")))
#endif

#endif