src/helper/types.h

   1 /***************************************************************************
   2  *   Copyright (C) 2004, 2005 by Dominic Rath                              *
   3  *   Dominic.Rath@gmx.de                                                   *
   4  *                                                                         *
   5  *   Copyright (C) 2007,2008 Øyvind Harboe                                 *
   6  *   oyvind.harboe@zylin.com                                               *
   7  *                                                                         *
   8  *   This program is free software; you can redistribute it and/or modify  *
   9  *   it under the terms of the GNU General Public License as published by  *
  10  *   the Free Software Foundation; either version 2 of the License, or     *
  11  *   (at your option) any later version.                                   *
  12  *                                                                         *
  13  *   This program is distributed in the hope that it will be useful,       *
  14  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  15  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  16  *   GNU General Public License for more details.                          *
  17  *                                                                         *
  18  *   You should have received a copy of the GNU General Public License     *
  19  *   along with this program.  If not, see <http://www.gnu.org/licenses/>. *
  20  ***************************************************************************/
  21 #ifndef TYPES_H
  22 #define TYPES_H
  23
  24 #include <stddef.h>
  25 #ifdef HAVE_SYS_TYPES_H
  26 #include <sys/types.h>
  27 #endif
  28 #ifdef HAVE_STDINT_H
  29 #include <stdint.h>
  30 #endif
  31 #ifdef HAVE_INTTYPES_H
  32 #include <inttypes.h>
  33 #endif
  34
  35 #ifdef HAVE_STDBOOL_H
  36 #include <stdbool.h>
  37 #else   /* HAVE_STDBOOL_H */
  38 #define __bool_true_false_are_defined 1
  39
  40 #ifndef HAVE__BOOL
  41 #ifndef __cplusplus
  42
  43 #define false   0
  44 #define true            1
  45
  46 typedef int _Bool;
  47 #else
  48 typedef bool _Bool;
  49 #endif  /* __cplusplus */
  50 #endif  /* HAVE__BOOL */
  51
  52 #define bool _Bool
  53
  54 #endif  /* HAVE_STDBOOL_H */
  55
  56 /// turns a macro argument into a string constant
  57 #define stringify(s) __stringify(s)
  58 #define __stringify(s) #s
  59
  60
  61 /**
  62  * Compute the number of elements of a variable length array.
  63  * <code>
  64  * const char *strs[] = { "a", "b", "c" };
  65  * unsigned num_strs = ARRAY_SIZE(strs);
  66  * </code>
  67  */
  68 #define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x)))
  69
  70
  71 /**
  72  * Cast a member of a structure out to the containing structure.
  73  * @param ptr The pointer to the member.
  74  * @param type The type of the container struct this is embedded in.
  75  * @param member The name of the member within the struct.
  76  *
  77  * This is a mechanism which is used throughout the Linux kernel.
  78  */
  79 #define container_of(ptr, type, member) ({                      \
  80         const typeof( ((type *)0)->member ) *__mptr = (ptr);    \
  81         (type *)( (void *) ( (char *)__mptr - offsetof(type,member) ) );})
  82
  83
  84 /**
  85  * Rounds @c m up to the nearest multiple of @c n using division.
  86  * @param m The value to round up to @c n.
  87  * @param n Round @c m up to a multiple of this number.
  88  * @returns The rounded integer value.
  89  */
  90 #define DIV_ROUND_UP(m, n)      (((m) + (n) - 1) / (n))
  91
  92
  93 /* DANGER!!!! here be dragons!
  94  *
  95  * Leave these fn's as byte accesses because it is safe
  96  * across architectures. Clever usage of 32 bit access
  97  * will create problems on some hosts.
  98  *
  99  * Note that the "buf" pointer in memory is probably unaligned.
 100  *
 101  * Were these functions to be re-written to take a 32 bit wide or 16 bit wide
 102  * memory access shortcut, then on some CPU's, i.e. ARM7, the 2 lsbytes of the address are
 103  * ignored for 32 bit access, whereas on other CPU's a 32 bit wide unaligned memory access
 104  * will cause an exception, and lastly on x86, an unaligned "greater than bytewide"
 105  * memory access works as if aligned.  So what follows below will work for all
 106  * platforms and gives the compiler leeway to do its own platform specific optimizations.
 107  *
 108  * Again, note that the "buf" pointer in memory is probably unaligned.
 109  */
 110
 111 static inline uint64_t le_to_h_u64(const uint8_t *buf)
 112 {
 113         return (uint64_t)((uint64_t)buf[0] |
 114                           (uint64_t)buf[1] << 8 |
 115                           (uint64_t)buf[2] << 16 |
 116                           (uint64_t)buf[3] << 24 |
 117                           (uint64_t)buf[4] << 32 |
 118                           (uint64_t)buf[5] << 40 |
 119                           (uint64_t)buf[6] << 48 |
 120                           (uint64_t)buf[7] << 56);
 121 }
 122
 123 static inline uint32_t le_to_h_u32(const uint8_t* buf)
 124 {
 125         return (uint32_t)(buf[0] | buf[1] << 8 | buf[2] << 16 | buf[3] << 24);
 126 }
 127
 128 static inline uint32_t le_to_h_u24(const uint8_t* buf)
 129 {
 130         return (uint32_t)(buf[0] | buf[1] << 8 | buf[2] << 16);
 131 }
 132
 133 static inline uint16_t le_to_h_u16(const uint8_t* buf)
 134 {
 135         return (uint16_t)(buf[0] | buf[1] << 8);
 136 }
 137
 138 static inline uint64_t be_to_h_u64(const uint8_t *buf)
 139 {
 140         return (uint64_t)((uint64_t)buf[7] |
 141                           (uint64_t)buf[6] << 8 |
 142                           (uint64_t)buf[5] << 16 |
 143                           (uint64_t)buf[4] << 24 |
 144                           (uint64_t)buf[3] << 32 |
 145                           (uint64_t)buf[2] << 40 |
 146                           (uint64_t)buf[1] << 48 |
 147                           (uint64_t)buf[0] << 56);
 148 }
 149
 150 static inline uint32_t be_to_h_u32(const uint8_t* buf)
 151 {
 152         return (uint32_t)(buf[3] | buf[2] << 8 | buf[1] << 16 | buf[0] << 24);
 153 }
 154
 155 static inline uint32_t be_to_h_u24(const uint8_t* buf)
 156 {
 157         return (uint32_t)(buf[2] | buf[1] << 8 | buf[0] << 16);
 158 }
 159
 160 static inline uint16_t be_to_h_u16(const uint8_t* buf)
 161 {
 162         return (uint16_t)(buf[1] | buf[0] << 8);
 163 }
 164
 165 static inline void h_u64_to_le(uint8_t *buf, int64_t val)
 166 {
 167         buf[7] = (uint8_t) (val >> 56);
 168         buf[6] = (uint8_t) (val >> 48);
 169         buf[5] = (uint8_t) (val >> 40);
 170         buf[4] = (uint8_t) (val >> 32);
 171         buf[3] = (uint8_t) (val >> 24);
 172         buf[2] = (uint8_t) (val >> 16);
 173         buf[1] = (uint8_t) (val >> 8);
 174         buf[0] = (uint8_t) (val >> 0);
 175 }
 176
 177 static inline void h_u64_to_be(uint8_t *buf, int64_t val)
 178 {
 179         buf[0] = (uint8_t) (val >> 56);
 180         buf[1] = (uint8_t) (val >> 48);
 181         buf[2] = (uint8_t) (val >> 40);
 182         buf[3] = (uint8_t) (val >> 32);
 183         buf[4] = (uint8_t) (val >> 24);
 184         buf[5] = (uint8_t) (val >> 16);
 185         buf[6] = (uint8_t) (val >> 8);
 186         buf[7] = (uint8_t) (val >> 0);
 187 }
 188
 189 static inline void h_u32_to_le(uint8_t* buf, int val)
 190 {
 191         buf[3] = (uint8_t) (val >> 24);
 192         buf[2] = (uint8_t) (val >> 16);
 193         buf[1] = (uint8_t) (val >> 8);
 194         buf[0] = (uint8_t) (val >> 0);
 195 }
 196
 197 static inline void h_u32_to_be(uint8_t* buf, int val)
 198 {
 199         buf[0] = (uint8_t) (val >> 24);
 200         buf[1] = (uint8_t) (val >> 16);
 201         buf[2] = (uint8_t) (val >> 8);
 202         buf[3] = (uint8_t) (val >> 0);
 203 }
 204
 205 static inline void h_u24_to_le(uint8_t* buf, int val)
 206 {
 207         buf[2] = (uint8_t) (val >> 16);
 208         buf[1] = (uint8_t) (val >> 8);
 209         buf[0] = (uint8_t) (val >> 0);
 210 }
 211
 212 static inline void h_u24_to_be(uint8_t* buf, int val)
 213 {
 214         buf[0] = (uint8_t) (val >> 16);
 215         buf[1] = (uint8_t) (val >> 8);
 216         buf[2] = (uint8_t) (val >> 0);
 217 }
 218
 219 static inline void h_u16_to_le(uint8_t* buf, int val)
 220 {
 221         buf[1] = (uint8_t) (val >> 8);
 222         buf[0] = (uint8_t) (val >> 0);
 223 }
 224
 225 static inline void h_u16_to_be(uint8_t* buf, int val)
 226 {
 227         buf[0] = (uint8_t) (val >> 8);
 228         buf[1] = (uint8_t) (val >> 0);
 229 }
 230
 231 /**
 232  * Byte-swap buffer 16-bit.
 233  *
 234  * Len must be even, dst and src must be either the same or non-overlapping.
 235  *
 236  * @param dst Destination buffer.
 237  * @param src Source buffer.
 238  * @param len Length of source (and destination) buffer, in bytes.
 239  */
 240 static inline void buf_bswap16(uint8_t *dst, const uint8_t *src, size_t len)
 241 {
 242         assert(len % 2 == 0);
 243         assert(dst == src || dst + len <= src || src + len <= dst);
 244
 245         for (size_t n = 0; n < len; n += 2) {
 246                 uint16_t x = be_to_h_u16(src + n);
 247                 h_u16_to_le(dst + n, x);
 248         }
 249 }
 250
 251 /**
 252  * Byte-swap buffer 32-bit.
 253  *
 254  * Len must be divisible by four, dst and src must be either the same or non-overlapping.
 255  *
 256  * @param dst Destination buffer.
 257  * @param src Source buffer.
 258  * @param len Length of source (and destination) buffer, in bytes.
 259  */
 260 static inline void buf_bswap32(uint8_t *dst, const uint8_t *src, size_t len)
 261 {
 262         assert(len % 4 == 0);
 263         assert(dst == src || dst + len <= src || src + len <= dst);
 264
 265         for (size_t n = 0; n < len; n += 4) {
 266                 uint32_t x = be_to_h_u32(src + n);
 267                 h_u32_to_le(dst + n, x);
 268         }
 269 }
 270
 271 /**
 272  * Calculate the (even) parity of a 32-bit datum.
 273  * @param x The datum.
 274  * @return 1 if the number of set bits in x is odd, 0 if it is even.
 275  */
 276 static inline int parity_u32(uint32_t x)
 277 {
 278 #ifdef __GNUC__
 279         return __builtin_parityl(x);
 280 #else
 281         x ^= x >> 16;
 282         x ^= x >> 8;
 283         x ^= x >> 4;
 284         x ^= x >> 2;
 285         x ^= x >> 1;
 286         return x & 1;
 287 #endif
 288 }
 289
 290 #if defined(__ECOS)
 291
 292 /* eCos plain lacks these definition... A series of upstream patches
 293  * could probably repair it, but it seems like too much work to be
 294  * worth it.
 295  */
 296
 297 #if !defined(_STDINT_H)
 298 #define PRIx32 "x"
 299 #define PRId32 "d"
 300 #define SCNx32 "x"
 301 #define PRIi32 "i"
 302 #define PRIu32 "u"
 303 #define PRId8 PRId32
 304 #define SCNx64 "llx"
 305 #define PRIx64 "llx"
 306
 307 typedef CYG_ADDRWORD intptr_t;
 308 typedef int64_t intmax_t;
 309 typedef uint64_t uintmax_t;
 310 #define INT8_MAX 0x7f
 311 #define INT8_MIN (-INT8_MAX - 1)
 312 # define UINT8_MAX              (255)
 313 #define INT16_MAX 0x7fff
 314 #define INT16_MIN (-INT16_MAX - 1)
 315 # define UINT16_MAX             (65535)
 316 #define INT32_MAX 0x7fffffffL
 317 #define INT32_MIN (-INT32_MAX - 1L)
 318 # define UINT32_MAX             (4294967295U)
 319 #define INT64_MAX 0x7fffffffffffffffLL
 320 #define INT64_MIN (-INT64_MAX - 1LL)
 321 #define UINT64_MAX (__CONCAT(INT64_MAX, U) * 2ULL + 1ULL)
 322 #endif
 323
 324         #ifndef LLONG_MAX
 325         #define ULLONG_MAX      UINT64_C(0xFFFFFFFFFFFFFFFF)
 326         #define LLONG_MAX       INT64_C(0x7FFFFFFFFFFFFFFF)
 327         #define LLONG_MIN       ULLONG_MAX
 328         #endif
 329
 330
 331 #define ULLONG_MAX 18446744073709551615
 332
 333 /* C99, eCos is C90 compliant (with bits of C99) */
 334 #define isblank(c) ((c) == ' ' || (c) == '\t')
 335
 336
 337 #endif
 338
 339 #endif /* TYPES_H */