1 /* 2 * Copyright (C) 2014 BlueKitchen GmbH 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the copyright holders nor the names of 14 * contributors may be used to endorse or promote products derived 15 * from this software without specific prior written permission. 16 * 4. Any redistribution, use, or modification is done solely for 17 * personal benefit and not for any commercial purpose or for 18 * monetary gain. 19 * 20 * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 23 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL BLUEKITCHEN 24 * GMBH OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 26 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 27 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 28 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 29 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF 30 * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * Please inquire about commercial licensing options at 34 * [email protected] 35 * 36 */ 37 38 /** 39 * @title General Utility Functions 40 * 41 */ 42 43 #ifndef BTSTACK_UTIL_H 44 #define BTSTACK_UTIL_H 45 46 47 #if defined __cplusplus 48 extern "C" { 49 #endif 50 51 #include <stdint.h> 52 #include <string.h> 53 54 #include "bluetooth.h" 55 #include "btstack_defines.h" 56 #include "btstack_linked_list.h" 57 58 // hack: compilation with the android ndk causes an error as there's a reverse_64 macro 59 #ifdef reverse_64 60 #undef reverse_64 61 #endif 62 63 // will be moved to daemon/btstack_device_name_db.h 64 65 66 /** 67 * @brief returns a value with number of lowest bits set to <1> 68 */ 69 #define N_BITS(value) ((1<<value) - 1) 70 71 /** 72 * @brief The device name type 73 */ 74 #define DEVICE_NAME_LEN 248 75 typedef uint8_t device_name_t[DEVICE_NAME_LEN+1]; 76 77 /* API_START */ 78 79 /** 80 * @brief Minimum function for uint32_t 81 * @param a 82 * @param b 83 * @return value 84 */ 85 uint32_t btstack_min(uint32_t a, uint32_t b); 86 87 /** 88 * @brief Maximum function for uint32_t 89 * @param a 90 * @param b 91 * @return value 92 */ 93 uint32_t btstack_max(uint32_t a, uint32_t b); 94 95 /** 96 * @brief Calculate delta between two uint32_t points in time 97 * @return time_a - time_b - result > 0 if time_a is newer than time_b 98 */ 99 int32_t btstack_time_delta(uint32_t time_a, uint32_t time_b); 100 101 /** 102 * @brief Calculate delta between two uint16_t points in time 103 * @return time_a - time_b - result > 0 if time_a is newer than time_b 104 */ 105 int16_t btstack_time16_delta(uint16_t time_a, uint16_t time_b); 106 107 /** 108 * @brief Read 08/16/24/32 bit little endian value from buffer 109 * @param buffer 110 * @param position in buffer 111 * @return value 112 */ 113 uint8_t little_endian_read_08(const uint8_t * buffer, int position); 114 uint16_t little_endian_read_16(const uint8_t * buffer, int position); 115 uint32_t little_endian_read_24(const uint8_t * buffer, int position); 116 uint32_t little_endian_read_32(const uint8_t * buffer, int position); 117 118 119 /** 120 * @brief Write 08/16/32 bit little endian value into buffer 121 * @param buffer 122 * @param position in buffer 123 * @param value 124 */ 125 void little_endian_store_08(uint8_t * buffer, uint16_t position, uint8_t value); 126 void little_endian_store_16(uint8_t * buffer, uint16_t position, uint16_t value); 127 void little_endian_store_24(uint8_t * buffer, uint16_t position, uint32_t value); 128 void little_endian_store_32(uint8_t * buffer, uint16_t position, uint32_t value); 129 130 /** 131 * @brief Read 08/16/24/32 bit big endian value from buffer 132 * @param buffer 133 * @param position in buffer 134 * @return value 135 */ 136 uint32_t big_endian_read_08(const uint8_t* buffer, int position); 137 uint32_t big_endian_read_16(const uint8_t * buffer, int position); 138 uint32_t big_endian_read_24(const uint8_t * buffer, int position); 139 uint32_t big_endian_read_32(const uint8_t * buffer, int position); 140 141 /** 142 * @brief Write 08/16/32 bit big endian value into buffer 143 * @param buffer 144 * @param position in buffer 145 * @param value 146 */ 147 void big_endian_store_08(uint8_t * buffer, uint16_t position, uint8_t value); 148 void big_endian_store_16(uint8_t * buffer, uint16_t position, uint16_t value); 149 void big_endian_store_24(uint8_t * buffer, uint16_t position, uint32_t value); 150 void big_endian_store_32(uint8_t * buffer, uint16_t position, uint32_t value); 151 152 153 /** 154 * @brief Swap bytes in 16 bit integer 155 */ 156 static inline uint16_t btstack_flip_16(uint16_t value){ 157 return (uint16_t)((value & 0xffu) << 8) | (value >> 8); 158 } 159 160 /** 161 * @brief Check for big endian system 162 * @return 1 if on big endian 163 */ 164 static inline int btstack_is_big_endian(void){ 165 uint16_t sample = 0x0100; 166 return (int) *(uint8_t*) &sample; 167 } 168 169 /** 170 * @brief Check for little endian system 171 * @return 1 if on little endian 172 */ 173 static inline int btstack_is_little_endian(void){ 174 uint16_t sample = 0x0001; 175 return (int) *(uint8_t*) &sample; 176 } 177 178 /** 179 * @brief Copy from source to destination and reverse byte order 180 * @param src 181 * @param dest 182 * @param len 183 */ 184 void reverse_bytes(const uint8_t * src, uint8_t * dest, int len); 185 186 /** 187 * @brief Wrapper around reverse_bytes for common buffer sizes 188 * @param src 189 * @param dest 190 */ 191 void reverse_24 (const uint8_t * src, uint8_t * dest); 192 void reverse_48 (const uint8_t * src, uint8_t * dest); 193 void reverse_56 (const uint8_t * src, uint8_t * dest); 194 void reverse_64 (const uint8_t * src, uint8_t * dest); 195 void reverse_128(const uint8_t * src, uint8_t * dest); 196 void reverse_256(const uint8_t * src, uint8_t * dest); 197 198 void reverse_bd_addr(const bd_addr_t src, bd_addr_t dest); 199 200 /** 201 * @brief Check if all bytes in buffer are zero 202 * @param buffer 203 * @param size 204 * @return true if all bytes is buffer are zero 205 */ 206 bool btstack_is_null(const uint8_t * buffer, uint16_t size); 207 208 /** 209 * @brief Check if all bytes in a bd_addr_t are zero 210 * @param addr 211 * @return true if all bytes in addr are zero 212 */ 213 bool btstack_is_null_bd_addr( const bd_addr_t addr ); 214 215 /** 216 * @brief ASCII character for 4-bit nibble 217 * @return character 218 */ 219 char char_for_nibble(uint8_t nibble); 220 221 /** 222 * @brif 4-bit nibble from ASCII character 223 * @return value 224 */ 225 int nibble_for_char(char c); 226 227 /** 228 * @brief Compare two Bluetooth addresses 229 * @param a 230 * @param b 231 * @return 0 if equal 232 */ 233 int bd_addr_cmp(const bd_addr_t a, const bd_addr_t b); 234 235 /** 236 * @brief Copy Bluetooth address 237 * @param dest 238 * @param src 239 */ 240 void bd_addr_copy(bd_addr_t dest, const bd_addr_t src); 241 242 /** 243 * @brief Use printf to write hexdump as single line of data 244 */ 245 void printf_hexdump(const void * data, int size); 246 247 /** 248 * @brief Create human readable representation for UUID128 249 * @note uses fixed global buffer 250 * @return pointer to UUID128 string 251 */ 252 char * uuid128_to_str(const uint8_t * uuid); 253 254 /** 255 * @brief Create human readable represenationt of Bluetooth address 256 * @note uses fixed global buffer 257 * @param delimiter 258 * @return pointer to Bluetooth address string 259 */ 260 char * bd_addr_to_str_with_delimiter(const bd_addr_t addr, char delimiter); 261 262 /** 263 * @brief Create human readable represenationt of Bluetooth address 264 * @note uses fixed global buffer 265 * @return pointer to Bluetooth address string 266 */ 267 char * bd_addr_to_str(const bd_addr_t addr); 268 269 /** 270 * @brief Replace address placeholder '00:00:00:00:00:00' with Bluetooth address 271 * @param buffer 272 * @param size 273 * @param address 274 */ 275 void btstack_replace_bd_addr_placeholder(uint8_t * buffer, uint16_t size, const bd_addr_t address); 276 277 /** 278 * @brief Parse Bluetooth address 279 * @param address_string 280 * @param buffer for parsed address 281 * @return 1 if string was parsed successfully 282 */ 283 int sscanf_bd_addr(const char * addr_string, bd_addr_t addr); 284 285 /** 286 * @brief Constructs UUID128 from 16 or 32 bit UUID using Bluetooth base UUID 287 * @param uuid128 output buffer 288 * @param short_uuid 289 */ 290 void uuid_add_bluetooth_prefix(uint8_t * uuid128, uint32_t short_uuid); 291 292 /** 293 * @brief Checks if UUID128 has Bluetooth base UUID prefix 294 * @param uui128 to test 295 * @return true if it can be expressed as UUID32 296 */ 297 bool uuid_has_bluetooth_prefix(const uint8_t * uuid128); 298 299 /** 300 * @brief Parse unsigned number 301 * @param str to parse 302 * @return value 303 */ 304 uint32_t btstack_atoi(const char * str); 305 306 /** 307 * @brief Return number of digits of a uint32 number 308 * @param uint32_number 309 * @return num_digits 310 */ 311 int string_len_for_uint32(uint32_t i); 312 313 /** 314 * @brief Return number of set bits in a uint32 number 315 * @param uint32_number 316 * @return num_set_bits 317 */ 318 int count_set_bits_uint32(uint32_t x); 319 320 /** 321 * @brief Check CRC8 using ETSI TS 101 369 V6.3.0. 322 * @note Only used by RFCOMM 323 * @param data 324 * @param len 325 * @param check_sum 326 */ 327 uint8_t btstack_crc8_check(uint8_t * data, uint16_t len, uint8_t check_sum); 328 329 /** 330 * @brief Calculate CRC8 using ETSI TS 101 369 V6.3.0. 331 * @note Only used by RFCOMM 332 * @param data 333 * @param len 334 */ 335 uint8_t btstack_crc8_calc(uint8_t * data, uint16_t len); 336 337 338 /** 339 * @brief Calculate the initial CRC32 value using ISO 3309 (HDLC), polynomial (normal) 0x04c11db7 340 * @note Used by OTS Service. 341 * 342 * @return The initial crc value. 343 */ 344 uint32_t btstack_crc32_init(void); 345 346 /** 347 * @brief Update the CRC32 value with new data. 348 * 349 * @param crc The current crc value. 350 * @param data Pointer to a buffer of \a data_len bytes. 351 * @param data_len Number of bytes in the \a data buffer. 352 * @return The updated crc value. 353 */ 354 uint32_t btstack_crc32_update(uint32_t crc, const uint8_t * data, uint32_t data_len); 355 356 /** 357 * @brief Calculate the final CRC32 value. 358 * 359 * @param crc The current crc value. 360 * @return The final crc value. 361 */ 362 uint32_t btstack_crc32_finalize(uint32_t crc); 363 364 /** 365 * @brief Get next cid 366 * @param current_cid 367 * @return next cid skiping 0 368 */ 369 uint16_t btstack_next_cid_ignoring_zero(uint16_t current_cid); 370 371 /** 372 * @brief Copy string (up to dst_size-1 characters) from src into dst buffer with terminating '\0' 373 * @note replaces strncpy + dst[dst_size-1] = '\0' 374 * @param dst 375 * @param dst_size 376 * @param src 377 * @retun bytes_copied including trailing 0 378 */ 379 uint16_t btstack_strcpy(char * dst, uint16_t dst_size, const char * src); 380 381 /** 382 * @brief Append src string to string in dst buffer with terminating '\0' 383 * @note max total string length will be dst_size-1 characters 384 * @param dst 385 * @param dst_size 386 * @param src 387 */ 388 void btstack_strcat(char * dst, uint16_t dst_size, const char * src); 389 390 /** 391 * @brief Calculated the number of characters that would get printed 392 * @note same as calling snprintf without a buffer 393 * @param format 394 * @param argsq 395 * @return number of characters, or negative value on error 396 */ 397 int btstack_printf_strlen(const char * format, ...) 398 #ifdef __GNUC__ 399 __attribute__ ((format (__printf__, 1, 2))) 400 #endif 401 ; 402 403 404 /** 405 * @brief Format string into buffer with '\0' and assert it is large enough 406 * @note same as calling snprintf and assert that the string was not truncated 407 * @param buffer 408 * @param size of buffer 409 * @param format 410 * @param argsq 411 * @return number of characters 412 */ 413 uint16_t btstack_snprintf_assert_complete(char * buffer, size_t size, const char * format, ...) 414 #ifdef __GNUC__ 415 __attribute__ ((format (__printf__, 3, 4))) 416 #endif 417 ; 418 419 /** 420 * @brief Format string into buffer, truncated if necessary. Output string is '\0' terminated 421 * @note similar to calling snprintf but returns the length of the output string 422 * @param buffer 423 * @param size of buffer 424 * @param format 425 * @param argsq 426 * @return number of characters 427 */ 428 uint16_t btstack_snprintf_best_effort(char * buffer, size_t size, const char * format, ...) 429 #ifdef __GNUC__ 430 __attribute__ ((format (__printf__, 3, 4))) 431 #endif 432 ; 433 434 /** 435 * Returns the number of leading 0-bits in x, starting at the most significant bit position. 436 * If x is 0, the result is undefined. 437 * @note maps to __builtin_clz for gcc and clang 438 * @param value 439 * @return number of leading 0-bits 440 */ 441 uint8_t btstack_clz(uint32_t value); 442 443 /** 444 * @brief Copy chunk of data into a virtual buffer backed by a physical buffer. 445 * Used to provide chunk of data of larger buffer that is constructed on the fly, e.g. serializing data struct 446 * 447 * For example, copy field2 to buffer, with buffer_offset = 11 448 * 449 * field1 field2 field3 field4 field5 filed6 450 * struct: -------|-------|----------|-------------|-------|-------------- 451 * buffer: ------------------ 452 * result: ----| 453 * 454 * When also copying field3 and field4 to buffer, with buffer_offset = 11 455 * 456 * field1 field2 field3 field4 field5 filed6 457 * struct: -------|-------|----------|-------------|-------|-------------- 458 * buffer: ------------------ 459 * result: ----|----------|-- 460 * 461 * @param field_data 462 * @param field_len 463 * @param field_offset position of field in complete data block 464 * @param buffer_data 465 * @param buffer_len 466 * @param buffer_offset position of buffer in complete data block 467 * @return bytes_copied number of bytes actually stored in buffer 468 */ 469 uint16_t btstack_virtual_memcpy( 470 const uint8_t * field_data, uint16_t field_len, uint16_t field_offset, 471 uint8_t * buffer, uint16_t buffer_size, uint16_t buffer_offset); 472 473 474 /* API_END */ 475 476 #if defined __cplusplus 477 } 478 #endif 479 480 #endif // BTSTACK_UTIL_H 481