xref: /btstack/src/btstack_util.h (revision 077fecbb6ed539507f37505ebd8a5b00e01c55e9)
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 The device name type
68  */
69 #define DEVICE_NAME_LEN 248
70 typedef uint8_t device_name_t[DEVICE_NAME_LEN+1];
71 
72 /* API_START */
73 
74 /**
75  * @brief Minimum function for uint32_t
76  * @param a
77  * @param b
78  * @return value
79  */
80 uint32_t btstack_min(uint32_t a, uint32_t b);
81 
82 /**
83  * @brief Maximum function for uint32_t
84  * @param a
85  * @param b
86  * @return value
87  */
88 uint32_t btstack_max(uint32_t a, uint32_t b);
89 
90 /**
91  * @brief Calculate delta between two points in time
92  * @return time_a - time_b - result > 0 if time_a is newer than time_b
93  */
94 int32_t btstack_time_delta(uint32_t time_a, uint32_t time_b);
95 
96 /**
97  * @brief Read 16/24/32 bit little endian value from buffer
98  * @param buffer
99  * @param position in buffer
100  * @return value
101  */
102 uint16_t little_endian_read_16(const uint8_t * buffer, int position);
103 uint32_t little_endian_read_24(const uint8_t * buffer, int position);
104 uint32_t little_endian_read_32(const uint8_t * buffer, int position);
105 
106 /**
107  * @brief Write 16/32 bit little endian value into buffer
108  * @param buffer
109  * @param position in buffer
110  * @param value
111  */
112 void little_endian_store_16(uint8_t * buffer, uint16_t position, uint16_t value);
113 void little_endian_store_24(uint8_t * buffer, uint16_t position, uint32_t value);
114 void little_endian_store_32(uint8_t * buffer, uint16_t position, uint32_t value);
115 
116 /**
117  * @brief Read 16/24/32 bit big endian value from buffer
118  * @param buffer
119  * @param position in buffer
120  * @return value
121  */
122 uint32_t big_endian_read_16(const uint8_t * buffer, int position);
123 uint32_t big_endian_read_24(const uint8_t * buffer, int position);
124 uint32_t big_endian_read_32(const uint8_t * buffer, int position);
125 
126 /**
127  * @brief Write 16/32 bit big endian value into buffer
128  * @param buffer
129  * @param position in buffer
130  * @param value
131  */
132 void big_endian_store_16(uint8_t * buffer, uint16_t position, uint16_t value);
133 void big_endian_store_24(uint8_t * buffer, uint16_t position, uint32_t value);
134 void big_endian_store_32(uint8_t * buffer, uint16_t position, uint32_t value);
135 
136 
137 /**
138  * @brief Swap bytes in 16 bit integer
139  */
140 static inline uint16_t btstack_flip_16(uint16_t value){
141     return (uint16_t)((value & 0xffu) << 8) | (value >> 8);
142 }
143 
144 /**
145  * @brief Check for big endian system
146  * @return 1 if on big endian
147  */
148 static inline int btstack_is_big_endian(void){
149 	uint16_t sample = 0x0100;
150 	return (int) *(uint8_t*) &sample;
151 }
152 
153 /**
154  * @brief Check for little endian system
155  * @return 1 if on little endian
156  */
157 static inline int btstack_is_little_endian(void){
158 	uint16_t sample = 0x0001;
159 	return (int) *(uint8_t*) &sample;
160 }
161 
162 /**
163  * @brief Copy from source to destination and reverse byte order
164  * @param src
165  * @param dest
166  * @param len
167  */
168 void reverse_bytes(const uint8_t * src, uint8_t * dest, int len);
169 
170 /**
171  * @brief Wrapper around reverse_bytes for common buffer sizes
172  * @param src
173  * @param dest
174  */
175 void reverse_24 (const uint8_t * src, uint8_t * dest);
176 void reverse_48 (const uint8_t * src, uint8_t * dest);
177 void reverse_56 (const uint8_t * src, uint8_t * dest);
178 void reverse_64 (const uint8_t * src, uint8_t * dest);
179 void reverse_128(const uint8_t * src, uint8_t * dest);
180 void reverse_256(const uint8_t * src, uint8_t * dest);
181 
182 void reverse_bd_addr(const bd_addr_t src, bd_addr_t dest);
183 
184 /**
185  * @brief ASCII character for 4-bit nibble
186  * @return character
187  */
188 char char_for_nibble(int nibble);
189 
190 /**
191  * @brif 4-bit nibble from ASCII character
192  * @return value
193  */
194 int nibble_for_char(char c);
195 
196 /**
197  * @brief Compare two Bluetooth addresses
198  * @param a
199  * @param b
200  * @return 0 if equal
201  */
202 int bd_addr_cmp(const bd_addr_t a, const bd_addr_t b);
203 
204 /**
205  * @brief Copy Bluetooth address
206  * @param dest
207  * @param src
208  */
209 void bd_addr_copy(bd_addr_t dest, const bd_addr_t src);
210 
211 /**
212  * @brief Use printf to write hexdump as single line of data
213  */
214 void printf_hexdump(const void * data, int size);
215 
216 /**
217  * @brief Create human readable representation for UUID128
218  * @note uses fixed global buffer
219  * @return pointer to UUID128 string
220  */
221 char * uuid128_to_str(const uint8_t * uuid);
222 
223 /**
224  * @brief Create human readable represenationt of Bluetooth address
225  * @note uses fixed global buffer
226  * @return pointer to Bluetooth address string
227  */
228 char * bd_addr_to_str(const bd_addr_t addr);
229 
230 /**
231  * @brief Replace address placeholder '00:00:00:00:00:00' with Bluetooth address
232  * @param buffer
233  * @param size
234  * @param address
235  */
236 void btstack_replace_bd_addr_placeholder(uint8_t * buffer, uint16_t size, const bd_addr_t address);
237 
238 /**
239  * @brief Parse Bluetooth address
240  * @param address_string
241  * @param buffer for parsed address
242  * @return 1 if string was parsed successfully
243  */
244 int sscanf_bd_addr(const char * addr_string, bd_addr_t addr);
245 
246 /**
247  * @brief Constructs UUID128 from 16 or 32 bit UUID using Bluetooth base UUID
248  * @param uuid128 output buffer
249  * @param short_uuid
250  */
251 void uuid_add_bluetooth_prefix(uint8_t * uuid128, uint32_t short_uuid);
252 
253 /**
254  * @brief Checks if UUID128 has Bluetooth base UUID prefix
255  * @param uui128 to test
256  * @return 1 if it can be expressed as UUID32
257  */
258 int  uuid_has_bluetooth_prefix(const uint8_t * uuid128);
259 
260 /**
261  * @brief Parse unsigned number
262  * @param str to parse
263  * @return value
264  */
265 uint32_t btstack_atoi(const char * str);
266 
267 /**
268  * @brief Return number of digits of a uint32 number
269  * @param uint32_number
270  * @return num_digits
271  */
272 int string_len_for_uint32(uint32_t i);
273 
274 /**
275  * @brief Return number of set bits in a uint32 number
276  * @param uint32_number
277  * @return num_set_bits
278  */
279 int count_set_bits_uint32(uint32_t x);
280 
281 /**
282  * @brief Check CRC8 using ETSI TS 101 369 V6.3.0.
283  * @note Only used by RFCOMM
284  * @param data
285  * @param len
286  * @param check_sum
287  */
288 uint8_t btstack_crc8_check(uint8_t * data, uint16_t len, uint8_t check_sum);
289 
290 /**
291  * @brief Calculate CRC8 using ETSI TS 101 369 V6.3.0.
292  * @note Only used by RFCOMM
293  * @param data
294  * @param len
295  */
296 uint8_t btstack_crc8_calc(uint8_t * data, uint16_t len);
297 
298 /**
299  * @brief Get next cid
300  * @param current_cid
301  * @return next cid skiping 0
302  */
303 uint16_t btstack_next_cid_ignoring_zero(uint16_t current_cid);
304 
305 /* API_END */
306 
307 #if defined __cplusplus
308 }
309 #endif
310 
311 #endif // BTSTACK_UTIL_H
312