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, write to the                         *
  20  *   Free Software Foundation, Inc.,                                       *
  21  *   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.           *
  22  ***************************************************************************/
  23 #ifndef TYPES_H
  24 #define TYPES_H
  25
  26 #include <stddef.h>
  27 #ifdef HAVE_SYS_TYPES_H
  28 #include <sys/types.h>
  29 #endif
  30 #ifdef HAVE_STDINT_H
  31 #include <stdint.h>
  32 #endif
  33 #ifdef HAVE_INTTYPES_H
  34 #include <inttypes.h>
  35 #endif
  36
  37 #ifdef HAVE_STDBOOL_H
  38 #include <stdbool.h>
  39 #else   /* HAVE_STDBOOL_H */
  40 #define __bool_true_false_are_defined 1
  41
  42 #ifndef HAVE__BOOL
  43 #ifndef __cplusplus
  44
  45 #define false   0
  46 #define true            1
  47
  48 typedef int _Bool;
  49 #else
  50 typedef bool _Bool;
  51 #endif  /* __cplusplus */
  52 #endif  /* HAVE__BOOL */
  53
  54 #define bool _Bool
  55
  56 #endif  /* HAVE_STDBOOL_H */
  57
  58 /// turns a macro argument into a string constant
  59 #define stringify(s) __stringify(s)
  60 #define __stringify(s) #s
  61
  62
  63 /**
  64  * Compute the number of elements of a variable length array.
  65  * <code>
  66  * const char *strs[] = { "a", "b", "c" };
  67  * unsigned num_strs = ARRAY_SIZE(strs);
  68  * </code>
  69  */
  70 #define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x)))
  71
  72
  73 /**
  74  * Cast a member of a structure out to the containing structure.
  75  * @param ptr The pointer to the member.
  76  * @param type The type of the container struct this is embedded in.
  77  * @param member The name of the member within the struct.
  78  *
  79  * This is a mechanism which is used throughout the Linux kernel.
  80  */
  81 #define container_of(ptr, type, member) ({                      \
  82         const typeof( ((type *)0)->member ) *__mptr = (ptr);    \
  83         (type *)( (void *) ( (char *)__mptr - offsetof(type,member) ) );})
  84
  85
  86 /**
  87  * Rounds @c m up to the nearest multiple of @c n using division.
  88  * @param m The value to round up to @c n.
  89  * @param n Round @c m up to a multiple of this number.
  90  * @returns The rounded integer value.
  91  */
  92 #define DIV_ROUND_UP(m, n)      (((m) + (n) - 1) / (n))
  93
  94
  95 /* DANGER!!!! here be dragons!
  96  *
  97  * Leave these fn's as byte accesses because it is safe
  98  * across architectures. Clever usage of 32 bit access
  99  * will create problems on some hosts.
 100  *
 101  * Note that the "buf" pointer in memory is probably unaligned.
 102  *
 103  * Were these functions to be re-written to take a 32 bit wide or 16 bit wide
 104  * memory access shortcut, then on some CPU's, i.e. ARM7, the 2 lsbytes of the address are
 105  * ignored for 32 bit access, whereas on other CPU's a 32 bit wide unaligned memory access
 106  * will cause an exception, and lastly on x86, an unaligned "greater than bytewide"
 107  * memory access works as if aligned.  So what follows below will work for all
 108  * platforms and gives the compiler leeway to do its own platform specific optimizations.
 109  *
 110  * Again, note that the "buf" pointer in memory is probably unaligned.
 111  */
 112
 113 static inline uint64_t le_to_h_u64(const uint8_t *buf)
 114 {
 115         return (uint64_t)((uint64_t)buf[0] |
 116                           (uint64_t)buf[1] << 8 |
 117                           (uint64_t)buf[2] << 16 |
 118                           (uint64_t)buf[3] << 24 |
 119                           (uint64_t)buf[4] << 32 |
 120                           (uint64_t)buf[5] << 40 |
 121                           (uint64_t)buf[6] << 48 |
 122                           (uint64_t)buf[7] << 56);
 123 }
 124
 125 static inline uint32_t le_to_h_u32(const uint8_t* buf)
 126 {
 127         return (uint32_t)(buf[0] | buf[1] << 8 | buf[2] << 16 | buf[3] << 24);
 128 }
 129
 130 static inline uint32_t le_to_h_u24(const uint8_t* buf)
 131 {
 132         return (uint32_t)(buf[0] | buf[1] << 8 | buf[2] << 16);
 133 }
 134
 135 static inline uint16_t le_to_h_u16(const uint8_t* buf)
 136 {
 137         return (uint16_t)(buf[0] | buf[1] << 8);
 138 }
 139
 140 static inline uint64_t be_to_h_u64(const uint8_t *buf)
 141 {
 142         return (uint64_t)((uint64_t)buf[7] |
 143                           (uint64_t)buf[6] << 8 |
 144                           (uint64_t)buf[5] << 16 |
 145                           (uint64_t)buf[4] << 24 |
 146                           (uint64_t)buf[3] << 32 |
 147                           (uint64_t)buf[2] << 40 |
 148                           (uint64_t)buf[1] << 48 |
 149                           (uint64_t)buf[0] << 56);
 150 }
 151
 152 static inline uint32_t be_to_h_u32(const uint8_t* buf)
 153 {
 154         return (uint32_t)(buf[3] | buf[2] << 8 | buf[1] << 16 | buf[0] << 24);
 155 }
 156
 157 static inline uint32_t be_to_h_u24(const uint8_t* buf)
 158 {
 159         return (uint32_t)(buf[2] | buf[1] << 8 | buf[0] << 16);
 160 }
 161
 162 static inline uint16_t be_to_h_u16(const uint8_t* buf)
 163 {
 164         return (uint16_t)(buf[1] | buf[0] << 8);
 165 }
 166
 167 static inline void h_u64_to_le(uint8_t *buf, int64_t val)
 168 {
 169         buf[7] = (uint8_t) (val >> 56);
 170         buf[6] = (uint8_t) (val >> 48);
 171         buf[5] = (uint8_t) (val >> 40);
 172         buf[4] = (uint8_t) (val >> 32);
 173         buf[3] = (uint8_t) (val >> 24);
 174         buf[2] = (uint8_t) (val >> 16);
 175         buf[1] = (uint8_t) (val >> 8);
 176         buf[0] = (uint8_t) (val >> 0);
 177 }
 178
 179 static inline void h_u64_to_be(uint8_t *buf, int64_t val)
 180 {
 181         buf[0] = (uint8_t) (val >> 56);
 182         buf[1] = (uint8_t) (val >> 48);
 183         buf[2] = (uint8_t) (val >> 40);
 184         buf[3] = (uint8_t) (val >> 32);
 185         buf[4] = (uint8_t) (val >> 24);
 186         buf[5] = (uint8_t) (val >> 16);
 187         buf[6] = (uint8_t) (val >> 8);
 188         buf[7] = (uint8_t) (val >> 0);
 189 }
 190
 191 static inline void h_u32_to_le(uint8_t* buf, int val)
 192 {
 193         buf[3] = (uint8_t) (val >> 24);
 194         buf[2] = (uint8_t) (val >> 16);
 195         buf[1] = (uint8_t) (val >> 8);
 196         buf[0] = (uint8_t) (val >> 0);
 197 }
 198
 199 static inline void h_u32_to_be(uint8_t* buf, int val)
 200 {
 201         buf[0] = (uint8_t) (val >> 24);
 202         buf[1] = (uint8_t) (val >> 16);
 203         buf[2] = (uint8_t) (val >> 8);
 204         buf[3] = (uint8_t) (val >> 0);
 205 }
 206
 207 static inline void h_u24_to_le(uint8_t* buf, int val)
 208 {
 209         buf[2] = (uint8_t) (val >> 16);
 210         buf[1] = (uint8_t) (val >> 8);
 211         buf[0] = (uint8_t) (val >> 0);
 212 }
 213
 214 static inline void h_u24_to_be(uint8_t* buf, int val)
 215 {
 216         buf[0] = (uint8_t) (val >> 16);
 217         buf[1] = (uint8_t) (val >> 8);
 218         buf[2] = (uint8_t) (val >> 0);
 219 }
 220
 221 static inline void h_u16_to_le(uint8_t* buf, int val)
 222 {
 223         buf[1] = (uint8_t) (val >> 8);
 224         buf[0] = (uint8_t) (val >> 0);
 225 }
 226
 227 static inline void h_u16_to_be(uint8_t* buf, int val)
 228 {
 229         buf[0] = (uint8_t) (val >> 8);
 230         buf[1] = (uint8_t) (val >> 0);
 231 }
 232
 233 /**
 234  * Byte-swap buffer 16-bit.
 235  *
 236  * Len must be even, dst and src must be either the same or non-overlapping.
 237  *
 238  * @param dst Destination buffer.
 239  * @param src Source buffer.
 240  * @param len Length of source (and destination) buffer, in bytes.
 241  */
 242 static inline void buf_bswap16(uint8_t *dst, const uint8_t *src, size_t len)
 243 {
 244         assert(len % 2 == 0);
 245         assert(dst == src || dst + len <= src || src + len <= dst);
 246
 247         for (size_t n = 0; n < len; n += 2) {
 248                 uint16_t x = be_to_h_u16(src + n);
 249                 h_u16_to_le(dst + n, x);
 250         }
 251 }
 252
 253 /**
 254  * Byte-swap buffer 32-bit.
 255  *
 256  * Len must be divisible by four, dst and src must be either the same or non-overlapping.
 257  *
 258  * @param dst Destination buffer.
 259  * @param src Source buffer.
 260  * @param len Length of source (and destination) buffer, in bytes.
 261  */
 262 static inline void buf_bswap32(uint8_t *dst, const uint8_t *src, size_t len)
 263 {
 264         assert(len % 4 == 0);
 265         assert(dst == src || dst + len <= src || src + len <= dst);
 266
 267         for (size_t n = 0; n < len; n += 4) {
 268                 uint32_t x = be_to_h_u32(src + n);
 269                 h_u32_to_le(dst + n, x);
 270         }
 271 }
 272
 273 /**
 274  * Calculate the (even) parity of a 32-bit datum.
 275  * @param x The datum.
 276  * @return 1 if the number of set bits in x is odd, 0 if it is even.
 277  */
 278 static inline int parity_u32(uint32_t x)
 279 {
 280 #ifdef __GNUC__
 281         return __builtin_parityl(x);
 282 #else
 283         x ^= x >> 16;
 284         x ^= x >> 8;
 285         x ^= x >> 4;
 286         x ^= x >> 2;
 287         x ^= x >> 1;
 288         return x & 1;
 289 #endif
 290 }
 291
 292 #if defined(__ECOS)
 293
 294 /* eCos plain lacks these definition... A series of upstream patches
 295  * could probably repair it, but it seems like too much work to be
 296  * worth it.
 297  */
 298
 299 #if !defined(_STDINT_H)
 300 #define PRIx32 "x"
 301 #define PRId32 "d"
 302 #define SCNx32 "x"
 303 #define PRIi32 "i"
 304 #define PRIu32 "u"
 305 #define PRId8 PRId32
 306 #define SCNx64 "llx"
 307 #define PRIx64 "llx"
 308
 309 typedef CYG_ADDRWORD intptr_t;
 310 typedef int64_t intmax_t;
 311 typedef uint64_t uintmax_t;
 312 #define INT8_MAX 0x7f
 313 #define INT8_MIN (-INT8_MAX - 1)
 314 # define UINT8_MAX              (255)
 315 #define INT16_MAX 0x7fff
 316 #define INT16_MIN (-INT16_MAX - 1)
 317 # define UINT16_MAX             (65535)
 318 #define INT32_MAX 0x7fffffffL
 319 #define INT32_MIN (-INT32_MAX - 1L)
 320 # define UINT32_MAX             (4294967295U)
 321 #define INT64_MAX 0x7fffffffffffffffLL
 322 #define INT64_MIN (-INT64_MAX - 1LL)
 323 #define UINT64_MAX (__CONCAT(INT64_MAX, U) * 2ULL + 1ULL)
 324 #endif
 325
 326         #ifndef LLONG_MAX
 327         #define ULLONG_MAX      UINT64_C(0xFFFFFFFFFFFFFFFF)
 328         #define LLONG_MAX       INT64_C(0x7FFFFFFFFFFFFFFF)
 329         #define LLONG_MIN       ULLONG_MAX
 330         #endif
 331
 332
 333 #define ULLONG_MAX 18446744073709551615
 334
 335 /* C99, eCos is C90 compliant (with bits of C99) */
 336 #define isblank(c) ((c) == ' ' || (c) == '\t')
 337
 338
 339 #endif
 340
 341 #endif /* TYPES_H */