utils.h

   1 /*
   2  * utils - misc libubox utility functions
   3  *
   4  * Copyright (C) 2012 Felix Fietkau <nbd@openwrt.org>
   5  *
   6  * Permission to use, copy, modify, and/or distribute this software for any
   7  * purpose with or without fee is hereby granted, provided that the above
   8  * copyright notice and this permission notice appear in all copies.
   9  *
  10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  17  */
  18
  19 #ifndef __LIBUBOX_UTILS_H
  20 #define __LIBUBOX_UTILS_H
  21
  22 #include <sys/types.h>
  23 #include <sys/time.h>
  24 #include <stdint.h>
  25 #include <stdbool.h>
  26 #include <unistd.h>
  27 #include <time.h>
  28
  29 /*
  30  * calloc_a(size_t len, [void **addr, size_t len,...], NULL)
  31  *
  32  * allocate a block of memory big enough to hold multiple aligned objects.
  33  * the pointer to the full object (starting with the first chunk) is returned,
  34  * all other pointers are stored in the locations behind extra addr arguments.
  35  * the last argument needs to be a NULL pointer
  36  */
  37
  38 #define calloc_a(len, ...) __calloc_a(len, ##__VA_ARGS__, NULL)
  39
  40 void *__calloc_a(size_t len, ...);
  41
  42 #ifndef ARRAY_SIZE
  43 #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
  44 #endif
  45
  46 #define __BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
  47
  48 #ifdef __OPTIMIZE__
  49 extern int __BUILD_BUG_ON_CONDITION_FAILED;
  50 #define BUILD_BUG_ON(condition)                                 \
  51         do {                                                    \
  52                 __BUILD_BUG_ON(condition);                      \
  53                 if (condition)                                  \
  54                         __BUILD_BUG_ON_CONDITION_FAILED = 1;    \
  55         } while(0)
  56 #else
  57 #define BUILD_BUG_ON __BUILD_BUG_ON
  58 #endif
  59
  60 #if defined(__APPLE__) && !defined(CLOCK_MONOTONIC)
  61 #define LIBUBOX_COMPAT_CLOCK_GETTIME
  62
  63 #include <mach/clock_types.h>
  64 #define CLOCK_REALTIME  CALENDAR_CLOCK
  65 #define CLOCK_MONOTONIC SYSTEM_CLOCK
  66
  67 int clock_gettime(int type, struct timespec *tv);
  68
  69 #endif
  70
  71 #ifdef __GNUC__
  72 #define _GNUC_MIN_VER(maj, min) (((__GNUC__ << 8) + __GNUC_MINOR__) >= (((maj) << 8) + (min)))
  73 #else
  74 #define _GNUC_MIN_VER(maj, min) 0
  75 #endif
  76
  77 #if defined(__linux__) || defined(__CYGWIN__)
  78 #include <byteswap.h>
  79 #include <endian.h>
  80
  81 #elif defined(__APPLE__)
  82 #include <machine/endian.h>
  83 #include <machine/byte_order.h>
  84 #elif defined(__FreeBSD__)
  85 #include <sys/endian.h>
  86 #else
  87 #include <machine/endian.h>
  88 #endif
  89
  90 #ifndef __BYTE_ORDER
  91 #define __BYTE_ORDER BYTE_ORDER
  92 #endif
  93 #ifndef __BIG_ENDIAN
  94 #define __BIG_ENDIAN BIG_ENDIAN
  95 #endif
  96 #ifndef __LITTLE_ENDIAN
  97 #define __LITTLE_ENDIAN LITTLE_ENDIAN
  98 #endif
  99
 100 #define __constant_swap16(x) ((uint16_t)(                               \
 101         (((uint16_t)(x) & (uint16_t)0x00ffU) << 8) |                    \
 102         (((uint16_t)(x) & (uint16_t)0xff00U) >> 8)))
 103
 104 #define __constant_swap32(x) ((uint32_t)(                               \
 105         (((uint32_t)(x) & (uint32_t)0x000000ffUL) << 24) |              \
 106         (((uint32_t)(x) & (uint32_t)0x0000ff00UL) <<  8) |              \
 107         (((uint32_t)(x) & (uint32_t)0x00ff0000UL) >>  8) |              \
 108         (((uint32_t)(x) & (uint32_t)0xff000000UL) >> 24)))
 109
 110 #define __constant_swap64(x) ((uint64_t)(                               \
 111         (((uint64_t)(x) & (uint64_t)0x00000000000000ffULL) << 56) |     \
 112         (((uint64_t)(x) & (uint64_t)0x000000000000ff00ULL) << 40) |     \
 113         (((uint64_t)(x) & (uint64_t)0x0000000000ff0000ULL) << 24) |     \
 114         (((uint64_t)(x) & (uint64_t)0x00000000ff000000ULL) <<  8) |     \
 115         (((uint64_t)(x) & (uint64_t)0x000000ff00000000ULL) >>  8) |     \
 116         (((uint64_t)(x) & (uint64_t)0x0000ff0000000000ULL) >> 24) |     \
 117         (((uint64_t)(x) & (uint64_t)0x00ff000000000000ULL) >> 40) |     \
 118         (((uint64_t)(x) & (uint64_t)0xff00000000000000ULL) >> 56)))
 119
 120 /*
 121  * This returns a constant expression while determining if an argument is
 122  * a constant expression, most importantly without evaluating the argument.
 123  */
 124 #define __is_constant(x)                                                \
 125         (sizeof(int) == sizeof(*(1 ? ((void*)((long)(x) * 0l)) : (int*)1)))
 126
 127 #define __eval_once(func, x)                                            \
 128         ({ __typeof__(x) __x = x; func(__x); })
 129
 130 #ifdef __cplusplus
 131 /*
 132  * g++ does not support __builtin_choose_expr, so always use __eval_once.
 133  * Unfortunately this means that the byte order functions can't be used
 134  * as a constant expression anymore
 135  */
 136 #define __eval_safe(func, x) __eval_once(func, x)
 137 #else
 138 #define __eval_safe(func, x)                                            \
 139         __builtin_choose_expr(__is_constant(x),                         \
 140                               func(x), __eval_once(func, x))
 141 #endif
 142
 143 #if __BYTE_ORDER == __LITTLE_ENDIAN
 144
 145 #define const_cpu_to_be64(x) __constant_swap64(x)
 146 #define const_cpu_to_be32(x) __constant_swap32(x)
 147 #define const_cpu_to_be16(x) __constant_swap16(x)
 148
 149 #define const_be64_to_cpu(x) __constant_swap64(x)
 150 #define const_be32_to_cpu(x) __constant_swap32(x)
 151 #define const_be16_to_cpu(x) __constant_swap16(x)
 152
 153 #define const_cpu_to_le64(x) (x)
 154 #define const_cpu_to_le32(x) (x)
 155 #define const_cpu_to_le16(x) (x)
 156
 157 #define const_le64_to_cpu(x) (x)
 158 #define const_le32_to_cpu(x) (x)
 159 #define const_le16_to_cpu(x) (x)
 160
 161 #define cpu_to_be64(x) __eval_safe(__constant_swap64, x)
 162 #define cpu_to_be32(x) __eval_safe(__constant_swap32, x)
 163 #define cpu_to_be16(x) __eval_safe(__constant_swap16, x)
 164
 165 #define be64_to_cpu(x) __eval_safe(__constant_swap64, x)
 166 #define be32_to_cpu(x) __eval_safe(__constant_swap32, x)
 167 #define be16_to_cpu(x) __eval_safe(__constant_swap16, x)
 168
 169 #define cpu_to_le64(x) (x)
 170 #define cpu_to_le32(x) (x)
 171 #define cpu_to_le16(x) (x)
 172
 173 #define le64_to_cpu(x) (x)
 174 #define le32_to_cpu(x) (x)
 175 #define le16_to_cpu(x) (x)
 176
 177 #else /* __BYTE_ORDER == __LITTLE_ENDIAN */
 178
 179 #define const_cpu_to_le64(x) __constant_swap64(x)
 180 #define const_cpu_to_le32(x) __constant_swap32(x)
 181 #define const_cpu_to_le16(x) __constant_swap16(x)
 182
 183 #define const_le64_to_cpu(x) __constant_swap64(x)
 184 #define const_le32_to_cpu(x) __constant_swap32(x)
 185 #define const_le16_to_cpu(x) __constant_swap16(x)
 186
 187 #define const_cpu_to_be64(x) (x)
 188 #define const_cpu_to_be32(x) (x)
 189 #define const_cpu_to_be16(x) (x)
 190
 191 #define const_be64_to_cpu(x) (x)
 192 #define const_be32_to_cpu(x) (x)
 193 #define const_be16_to_cpu(x) (x)
 194
 195 #define cpu_to_le64(x) __eval_safe(__constant_swap64, x)
 196 #define cpu_to_le32(x) __eval_safe(__constant_swap32, x)
 197 #define cpu_to_le16(x) __eval_safe(__constant_swap16, x)
 198
 199 #define le64_to_cpu(x) __eval_safe(__constant_swap64, x)
 200 #define le32_to_cpu(x) __eval_safe(__constant_swap32, x)
 201 #define le16_to_cpu(x) __eval_safe(__constant_swap16, x)
 202
 203 #define cpu_to_be64(x) (x)
 204 #define cpu_to_be32(x) (x)
 205 #define cpu_to_be16(x) (x)
 206
 207 #define be64_to_cpu(x) (x)
 208 #define be32_to_cpu(x) (x)
 209 #define be16_to_cpu(x) (x)
 210
 211 #endif
 212
 213 #ifndef __packed
 214 #define __packed __attribute__((packed))
 215 #endif
 216
 217 #ifndef __constructor
 218 #define __constructor __attribute__((constructor))
 219 #endif
 220
 221 #ifndef __destructor
 222 #define __destructor __attribute__((destructor))
 223 #endif
 224
 225 #ifndef __hidden
 226 #define __hidden __attribute__((visibility("hidden")))
 227 #endif
 228
 229 int b64_encode(const void *src, size_t src_len,
 230                void *dest, size_t dest_len);
 231
 232 int b64_decode(const void *src, void *dest, size_t dest_len);
 233
 234 #define B64_ENCODE_LEN(_len)    ((((_len) + 2) / 3) * 4 + 1)
 235 #define B64_DECODE_LEN(_len)    (((_len) / 4) * 3 + 1)
 236
 237 static inline unsigned int cbuf_order(unsigned int x)
 238 {
 239         return 32 - __builtin_clz(x - 1);
 240 }
 241
 242 static inline unsigned long cbuf_size(int order)
 243 {
 244         unsigned long page_size = sysconf(_SC_PAGESIZE);
 245         unsigned long ret = 1ULL << order;
 246
 247         if (ret < page_size)
 248                 ret = page_size;
 249
 250         return ret;
 251 }
 252
 253 void *cbuf_alloc(unsigned int order);
 254 void cbuf_free(void *ptr, unsigned int order);
 255
 256 #endif