common.h

#ifndef COMMON_H
#define COMMON_H

#define _LARGEFILE64_SOURCE
#define _FILE_OFFSET_BITS 64
#define _DARWIN_USE_64_BIT_INODE

#include <fcntl.h>
#include <sys/errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <inttypes.h>

#include "banned.h"

#define MAGIC_OFFSET ((uint64_t) 1572864u)
#define IMAGE_SIZE ((uint64_t) 1474560u)
#define LABEL_OFFSET 3u
#define IMAGES_GAP 98304

#define FAT_MAGIC_1 0xEB3C9000u
#define FAT_MAGIC_2 0xEB3E9000u
#define FAT_MAGIC_3 0xEB3F9000u
#define FAT_MAGIC_4 0xEB1E9000u
#define GOTEK_MAX_FDDS 1000u

#define NONNULLARGS __attribute__((nonnull)) 

enum RET_CODES
{
    FAIL_COMPILER   = -1, /* makes compiler happy and allows implicit conversion to int without warning */
    FAIL_SUCC       = EXIT_SUCCESS,
	FAIL_ARGS       = 1,
	FAIL_OPEN       = 2,
	FAIL_LSEEK      = 10,
	FAIL_READ       = 11,
	FAIL_WRITE      = 12,
	FAIL_CLOSE      = 13,
    FAIL_FSTAT      = 14,
	FAIL_IOCTL      = 20,
    FAIL_MMAP       = 30,
    FAIL_CHRNOTSUPP = 40,
    FAIL_NOTSUPP    = 41,
    FAIL_NOMETA     = 45,
    FAIL_FAIL       = 50,
};

#define CHECK_ERROR_GENERIC(f, t, e) ({ \
    __typeof__(t) __rc = (f);                                             \
    if (__rc == -1) {                                                     \
        fprintf(stderr, "%s: %s: %s\n", __func__, #f, strerror(errno)); \
        return((e));                                                    \
    }                                                                   \
    __rc;                                                                 \
})

#define CHECK_ERROR(f, e) CHECK_ERROR_GENERIC(f, int, e)

#define CHECK_ERROR_MMAP(f, e) ({                                       \
    void *__rc_p = (f);                                                   \
    if (__rc_p == MAP_FAILED) {                                           \
        fprintf(stderr, "%s: %s: %s\n", __func__, #f, strerror(errno)); \
        return((e));                                                    \
    }                                                                   \
    __rc_p;                                                               \
})

#define CHECK_ERROR_NOVALRET(f, e) (void)CHECK_ERROR_GENERIC(f, int, e)

/* Functions */
void safe_close(int *const fd);

/* Macros */
#define BSWAP16(value) \
((((value) & 0xff) << 8) | ((value) >> 8))

#define BSWAP32(value) \
(((uint32_t)BSWAP16_ONLY_ON_LE((uint16_t)((value) & 0xffff)) << 16) | \
(uint32_t)BSWAP16_ONLY_ON_LE((uint16_t)((value) >> 16)))

/* Compatibility */
#if defined(__APPLE__) && defined(__MACH__)

#define ADDITIONAL_OPEN_FLAGS 0

#if defined(__BIG_ENDIAN__)

#define BSWAP16_ONLY_ON_LE(value) (value)
#define BSWAP32_ONLY_ON_LE(value) (value)

#define BSWAP16_ONLY_ON_BE(value) BSWAP16(value)
#define BSWAP32_ONLY_ON_BE(value) BSWAP32(value)

#else

#define BSWAP16_ONLY_ON_LE(value) BSWAP16(value)
#define BSWAP32_ONLY_ON_LE(value) BSWAP32(value)

#define BSWAP16_ONLY_ON_BE(value) (value)
#define BSWAP32_ONLY_ON_BE(value) (value)

#endif

#elif defined(__linux__)

#include <endian.h>

#if BYTE_ORDER == LITTLE_ENDIAN

#define BSWAP16_ONLY_ON_LE(value) (htobe16(value))
#define BSWAP32_ONLY_ON_LE(value) (htobe32(value))

#define BSWAP16_ONLY_ON_BE(value) (value)
#define BSWAP32_ONLY_ON_BE(value) (value)

#else

#define BSWAP16_ONLY_ON_LE(value) (value)
#define BSWAP32_ONLY_ON_LE(value) (value)

#define BSWAP16_ONLY_ON_BE(value) (htobe16(value))
#define BSWAP32_ONLY_ON_BE(value) (htobe32(value))

#endif

#define ADDITIONAL_OPEN_FLAGS O_LARGEFILE

#endif /* MACOS and Linux checks */

#endif /* COMMON_H */