include/bitops.h

   1 /*
   2  * No copyright is claimed.  This code is in the public domain; do with
   3  * it what you wish.
   4  *
   5  * Written by Karel Zak <kzak@redhat.com>
   6  */
   7 #ifndef BITOPS_H
   8 #define BITOPS_H
   9
  10 #include <stdint.h>
  11 #include <sys/param.h>
  12
  13 #if defined(HAVE_BYTESWAP_H)
  14 # include <byteswap.h>
  15 #endif
  16
  17 #if defined(HAVE_ENDIAN_H)
  18 #  include <endian.h>
  19 #elif defined(HAVE_SYS_ENDIAN_H)        /* BSDs have them here */
  20 #  include <sys/endian.h>
  21 #endif
  22
  23 #if defined(__OpenBSD__)
  24 # include <sys/types.h>
  25 # define be16toh(x) betoh16(x)
  26 # define be32toh(x) betoh32(x)
  27 # define be64toh(x) betoh64(x)
  28 #elif defined(__NetBSD__) || defined(__FreeBSD__) || defined(__DragonFly__)
  29 # define bswap_16(x) bswap16(x)
  30 # define bswap_32(x) bswap32(x)
  31 # define bswap_64(x) bswap64(x)
  32 #elif defined(__APPLE__)
  33 # include <libkern/OSByteOrder.h>
  34 # define htobe16(x) OSSwapHostToBigInt16(x)
  35 # define htole16(x) OSSwapHostToLittleInt16(x)
  36 # define be16toh(x) OSSwapBigToHostInt16(x)
  37 # define le16toh(x) OSSwapLittleToHostInt16(x)
  38 # define htobe32(x) OSSwapHostToBigInt32(x)
  39 # define htole32(x) OSSwapHostToLittleInt32(x)
  40 # define be32toh(x) OSSwapBigToHostInt32(x)
  41 # define le32toh(x) OSSwapLittleToHostInt32(x)
  42 # define htobe64(x) OSSwapHostToBigInt64(x)
  43 # define htole64(x) OSSwapHostToLittleInt64(x)
  44 # define be64toh(x) OSSwapBigToHostInt64(x)
  45 # define le64toh(x) OSSwapLittleToHostInt64(x)
  46 # define bswap_16(x) OSSwapInt16(x)
  47 # define bswap_32(x) OSSwapInt32(x)
  48 # define bswap_64(x) OSSwapInt64(x)
  49 #endif
  50
  51 /*
  52  * Fallbacks
  53  * casts are necessary for constants, because we never know how for sure
  54  * how U/UL/ULL map to __u16, __u32, __u64. At least not in a portable way.
  55  */
  56 #ifndef bswap_16
  57 # define bswap_16(x) ((uint16_t)( \
  58         (((uint16_t)(x) & 0x00FF) << 8) | \
  59         (((uint16_t)(x) & 0xFF00) >> 8)))
  60 #endif
  61
  62 #ifndef bswap_32
  63 # define bswap_32(x) ((uint32_t)( \
  64         (((uint32_t)(x) & 0x000000FF) << 24) | \
  65         (((uint32_t)(x) & 0x0000FF00) << 8)  | \
  66         (((uint32_t)(x) & 0x00FF0000) >> 8)  | \
  67         (((uint32_t)(x) & 0xFF000000) >> 24)))
  68 #endif
  69
  70 #ifndef bswap_64
  71 # define bswap_64(x) ((uint64_t)( \
  72         (((uint64_t)(x) & 0x00000000000000FFULL) << 56) | \
  73         (((uint64_t)(x) & 0x000000000000FF00ULL) << 40) | \
  74         (((uint64_t)(x) & 0x0000000000FF0000ULL) << 24) | \
  75         (((uint64_t)(x) & 0x00000000FF000000ULL) << 8)  | \
  76         (((uint64_t)(x) & 0x000000FF00000000ULL) >> 8)  | \
  77         (((uint64_t)(x) & 0x0000FF0000000000ULL) >> 24) | \
  78         (((uint64_t)(x) & 0x00FF000000000000ULL) >> 40) | \
  79         (((uint64_t)(x) & 0xFF00000000000000ULL) >> 56)))
  80 #endif
  81
  82 #ifndef htobe16
  83 # if !defined(WORDS_BIGENDIAN)
  84 #  define htobe16(x) bswap_16 (x)
  85 #  define htole16(x) (x)
  86 #  define be16toh(x) bswap_16 (x)
  87 #  define le16toh(x) (x)
  88 #  define htobe32(x) bswap_32 (x)
  89 #  define htole32(x) (x)
  90 #  define be32toh(x) bswap_32 (x)
  91 #  define le32toh(x) (x)
  92 #  define htobe64(x) bswap_64 (x)
  93 #  define htole64(x) (x)
  94 #  define be64toh(x) bswap_64 (x)
  95 #  define le64toh(x) (x)
  96 # else
  97 #  define htobe16(x) (x)
  98 #  define htole16(x) bswap_16 (x)
  99 #  define be16toh(x) (x)
 100 #  define le16toh(x) bswap_16 (x)
 101 #  define htobe32(x) (x)
 102 #  define htole32(x) bswap_32 (x)
 103 #  define be32toh(x) (x)
 104 #  define le32toh(x) bswap_32 (x)
 105 #  define htobe64(x) (x)
 106 #  define htole64(x) bswap_64 (x)
 107 #  define be64toh(x) (x)
 108 #  define le64toh(x) bswap_64 (x)
 109 # endif
 110 #endif
 111
 112 /*
 113  * Byte swab macros (based on linux/byteorder/swab.h)
 114  */
 115 #define swab16(x) bswap_16(x)
 116 #define swab32(x) bswap_32(x)
 117 #define swab64(x) bswap_64(x)
 118
 119 #define cpu_to_le16(x) ((uint16_t) htole16(x))
 120 #define cpu_to_le32(x) ((uint32_t) htole32(x))
 121 #define cpu_to_le64(x) ((uint64_t) htole64(x))
 122
 123 #define cpu_to_be16(x) ((uint16_t) htobe16(x))
 124 #define cpu_to_be32(x) ((uint32_t) htobe32(x))
 125 #define cpu_to_be64(x) ((uint64_t) htobe64(x))
 126
 127 #define le16_to_cpu(x) ((uint16_t) le16toh(x))
 128 #define le32_to_cpu(x) ((uint32_t) le32toh(x))
 129 #define le64_to_cpu(x) ((uint64_t) le64toh(x))
 130
 131 #define be16_to_cpu(x) ((uint16_t) be16toh(x))
 132 #define be32_to_cpu(x) ((uint32_t) be32toh(x))
 133 #define be64_to_cpu(x) ((uint64_t) be64toh(x))
 134
 135 /*
 136  * Bit map related macros. Usually provided by libc.
 137  */
 138 #ifndef NBBY
 139 # define NBBY            CHAR_BIT
 140 #endif
 141
 142 #ifndef setbit
 143 # define setbit(a,i)    ((a)[(i)/NBBY] |= 1<<((i)%NBBY))
 144 # define clrbit(a,i)    ((a)[(i)/NBBY] &= ~(1<<((i)%NBBY)))
 145 # define isset(a,i)     ((a)[(i)/NBBY] & (1<<((i)%NBBY)))
 146 # define isclr(a,i)     (((a)[(i)/NBBY] & (1<<((i)%NBBY))) == 0)
 147 #endif
 148
 149 #endif /* BITOPS_H */
 150