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/stat.h>
  23 #include <sys/types.h>
  24 #include <sys/time.h>
  25 #include <stdint.h>
  26 #include <stdbool.h>
  27 #include <unistd.h>
  28 #include <time.h>
  29
  30 /*
  31  * calloc_a(size_t len, [void **addr, size_t len,...], NULL)
  32  *
  33  * allocate a block of memory big enough to hold multiple aligned objects.
  34  * the pointer to the full object (starting with the first chunk) is returned,
  35  * all other pointers are stored in the locations behind extra addr arguments.
  36  * the last argument needs to be a NULL pointer
  37  */
  38
  39 #define calloc_a(len, ...) __calloc_a(len, ##__VA_ARGS__, NULL)
  40
  41 void *__calloc_a(size_t len, ...);
  42
  43 #ifndef ARRAY_SIZE
  44 #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
  45 #endif
  46
  47 #define __BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
  48
  49 #ifdef __OPTIMIZE__
  50 extern int __BUILD_BUG_ON_CONDITION_FAILED;
  51 #define BUILD_BUG_ON(condition)                                 \
  52         do {                                                    \
  53                 __BUILD_BUG_ON(condition);                      \
  54                 if (condition)                                  \
  55                         __BUILD_BUG_ON_CONDITION_FAILED = 1;    \
  56         } while(0)
  57 #else
  58 #define BUILD_BUG_ON __BUILD_BUG_ON
  59 #endif
  60
  61 #if defined(__APPLE__) && !defined(CLOCK_MONOTONIC)
  62 #define LIBUBOX_COMPAT_CLOCK_GETTIME
  63
  64 #include <mach/clock_types.h>
  65 #define CLOCK_REALTIME  CALENDAR_CLOCK
  66 #define CLOCK_MONOTONIC SYSTEM_CLOCK
  67
  68 int clock_gettime(int type, struct timespec *tv);
  69
  70 #endif
  71
  72 #ifdef __GNUC__
  73 #define _GNUC_MIN_VER(maj, min) (((__GNUC__ << 8) + __GNUC_MINOR__) >= (((maj) << 8) + (min)))
  74 #else
  75 #define _GNUC_MIN_VER(maj, min) 0
  76 #endif
  77
  78 #if defined(__linux__) || defined(__CYGWIN__)
  79 #include <byteswap.h>
  80 #include <endian.h>
  81
  82 #elif defined(__APPLE__)
  83 #include <machine/endian.h>
  84 #include <machine/byte_order.h>
  85 #elif defined(__FreeBSD__)
  86 #include <sys/endian.h>
  87 #else
  88 #include <machine/endian.h>
  89 #endif
  90
  91 #ifndef __BYTE_ORDER
  92 #define __BYTE_ORDER BYTE_ORDER
  93 #endif
  94 #ifndef __BIG_ENDIAN
  95 #define __BIG_ENDIAN BIG_ENDIAN
  96 #endif
  97 #ifndef __LITTLE_ENDIAN
  98 #define __LITTLE_ENDIAN LITTLE_ENDIAN
  99 #endif
 100
 101 #define __constant_swap16(x) ((uint16_t)(                               \
 102         (((uint16_t)(x) & (uint16_t)0x00ffU) << 8) |                    \
 103         (((uint16_t)(x) & (uint16_t)0xff00U) >> 8)))
 104
 105 #define __constant_swap32(x) ((uint32_t)(                               \
 106         (((uint32_t)(x) & (uint32_t)0x000000ffUL) << 24) |              \
 107         (((uint32_t)(x) & (uint32_t)0x0000ff00UL) <<  8) |              \
 108         (((uint32_t)(x) & (uint32_t)0x00ff0000UL) >>  8) |              \
 109         (((uint32_t)(x) & (uint32_t)0xff000000UL) >> 24)))
 110
 111 #define __constant_swap64(x) ((uint64_t)(                               \
 112         (((uint64_t)(x) & (uint64_t)0x00000000000000ffULL) << 56) |     \
 113         (((uint64_t)(x) & (uint64_t)0x000000000000ff00ULL) << 40) |     \
 114         (((uint64_t)(x) & (uint64_t)0x0000000000ff0000ULL) << 24) |     \
 115         (((uint64_t)(x) & (uint64_t)0x00000000ff000000ULL) <<  8) |     \
 116         (((uint64_t)(x) & (uint64_t)0x000000ff00000000ULL) >>  8) |     \
 117         (((uint64_t)(x) & (uint64_t)0x0000ff0000000000ULL) >> 24) |     \
 118         (((uint64_t)(x) & (uint64_t)0x00ff000000000000ULL) >> 40) |     \
 119         (((uint64_t)(x) & (uint64_t)0xff00000000000000ULL) >> 56)))
 120
 121 /*
 122  * This returns a constant expression while determining if an argument is
 123  * a constant expression, most importantly without evaluating the argument.
 124  */
 125 #define __is_constant(x)                                                \
 126         (sizeof(int) == sizeof(*(1 ? ((void*)((long)(x) * 0l)) : (int*)1)))
 127
 128 #define __eval_once(func, x)                                            \
 129         ({ __typeof__(x) __x = x; func(__x); })
 130
 131 #ifdef __cplusplus
 132 /*
 133  * g++ does not support __builtin_choose_expr, so always use __eval_once.
 134  * Unfortunately this means that the byte order functions can't be used
 135  * as a constant expression anymore
 136  */
 137 #define __eval_safe(func, x) __eval_once(func, x)
 138 #else
 139 #define __eval_safe(func, x)                                            \
 140         __builtin_choose_expr(__is_constant(x),                         \
 141                               func(x), __eval_once(func, x))
 142 #endif
 143
 144 #if __BYTE_ORDER == __LITTLE_ENDIAN
 145
 146 #define const_cpu_to_be64(x) __constant_swap64(x)
 147 #define const_cpu_to_be32(x) __constant_swap32(x)
 148 #define const_cpu_to_be16(x) __constant_swap16(x)
 149
 150 #define const_be64_to_cpu(x) __constant_swap64(x)
 151 #define const_be32_to_cpu(x) __constant_swap32(x)
 152 #define const_be16_to_cpu(x) __constant_swap16(x)
 153
 154 #define const_cpu_to_le64(x) (x)
 155 #define const_cpu_to_le32(x) (x)
 156 #define const_cpu_to_le16(x) (x)
 157
 158 #define const_le64_to_cpu(x) (x)
 159 #define const_le32_to_cpu(x) (x)
 160 #define const_le16_to_cpu(x) (x)
 161
 162 #define cpu_to_be64(x) __eval_safe(__constant_swap64, x)
 163 #define cpu_to_be32(x) __eval_safe(__constant_swap32, x)
 164 #define cpu_to_be16(x) __eval_safe(__constant_swap16, x)
 165
 166 #define be64_to_cpu(x) __eval_safe(__constant_swap64, x)
 167 #define be32_to_cpu(x) __eval_safe(__constant_swap32, x)
 168 #define be16_to_cpu(x) __eval_safe(__constant_swap16, x)
 169
 170 #define cpu_to_le64(x) (x)
 171 #define cpu_to_le32(x) (x)
 172 #define cpu_to_le16(x) (x)
 173
 174 #define le64_to_cpu(x) (x)
 175 #define le32_to_cpu(x) (x)
 176 #define le16_to_cpu(x) (x)
 177
 178 #else /* __BYTE_ORDER == __LITTLE_ENDIAN */
 179
 180 #define const_cpu_to_le64(x) __constant_swap64(x)
 181 #define const_cpu_to_le32(x) __constant_swap32(x)
 182 #define const_cpu_to_le16(x) __constant_swap16(x)
 183
 184 #define const_le64_to_cpu(x) __constant_swap64(x)
 185 #define const_le32_to_cpu(x) __constant_swap32(x)
 186 #define const_le16_to_cpu(x) __constant_swap16(x)
 187
 188 #define const_cpu_to_be64(x) (x)
 189 #define const_cpu_to_be32(x) (x)
 190 #define const_cpu_to_be16(x) (x)
 191
 192 #define const_be64_to_cpu(x) (x)
 193 #define const_be32_to_cpu(x) (x)
 194 #define const_be16_to_cpu(x) (x)
 195
 196 #define cpu_to_le64(x) __eval_safe(__constant_swap64, x)
 197 #define cpu_to_le32(x) __eval_safe(__constant_swap32, x)
 198 #define cpu_to_le16(x) __eval_safe(__constant_swap16, x)
 199
 200 #define le64_to_cpu(x) __eval_safe(__constant_swap64, x)
 201 #define le32_to_cpu(x) __eval_safe(__constant_swap32, x)
 202 #define le16_to_cpu(x) __eval_safe(__constant_swap16, x)
 203
 204 #define cpu_to_be64(x) (x)
 205 #define cpu_to_be32(x) (x)
 206 #define cpu_to_be16(x) (x)
 207
 208 #define be64_to_cpu(x) (x)
 209 #define be32_to_cpu(x) (x)
 210 #define be16_to_cpu(x) (x)
 211
 212 #endif
 213
 214 #ifndef __packed
 215 #define __packed __attribute__((packed))
 216 #endif
 217
 218 #ifndef __constructor
 219 #define __constructor __attribute__((constructor))
 220 #endif
 221
 222 #ifndef __destructor
 223 #define __destructor __attribute__((destructor))
 224 #endif
 225
 226 #ifndef __hidden
 227 #define __hidden __attribute__((visibility("hidden")))
 228 #endif
 229
 230 int b64_encode(const void *src, size_t src_len,
 231                void *dest, size_t dest_len);
 232
 233 int b64_decode(const void *src, void *dest, size_t dest_len);
 234
 235 #define B64_ENCODE_LEN(_len)    ((((_len) + 2) / 3) * 4 + 1)
 236 #define B64_DECODE_LEN(_len)    (((_len) / 4) * 3 + 1)
 237
 238 static inline unsigned int cbuf_order(unsigned int x)
 239 {
 240         return 32 - __builtin_clz(x - 1);
 241 }
 242
 243 static inline unsigned long cbuf_size(int order)
 244 {
 245         unsigned long page_size = sysconf(_SC_PAGESIZE);
 246         unsigned long ret = 1ULL << order;
 247
 248         if (ret < page_size)
 249                 ret = page_size;
 250
 251         return ret;
 252 }
 253
 254 void *cbuf_alloc(unsigned int order);
 255 void cbuf_free(void *ptr, unsigned int order);
 256 int mkdir_p(char *dir, mode_t mask);
 257
 258 #endif