xref: /btstack/src/btstack_util.c (revision bc37f7b0d0a3eaa5763a873c5730bc14b849aaa0)
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 MATTHIAS
24  * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
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26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
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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  *  btstack_util.c
40  *
41  *  General utility functions
42  *
43  *  Created by Matthias Ringwald on 7/23/09.
44  */
45 
46 #include "btstack_config.h"
47 #include "btstack_debug.h"
48 #include "btstack_util.h"
49 
50 #include <stdio.h>
51 #include <string.h>
52 
53 
54 /**
55  * @brief Compare two Bluetooth addresses
56  * @param a
57  * @param b
58  * @return 0 if equal
59  */
60 int bd_addr_cmp(bd_addr_t a, bd_addr_t b){
61     return memcmp(a,b, BD_ADDR_LEN);
62 }
63 
64 /**
65  * @brief Copy Bluetooth address
66  * @param dest
67  * @param src
68  */
69 void bd_addr_copy(bd_addr_t dest, bd_addr_t src){
70     memcpy(dest,src,BD_ADDR_LEN);
71 }
72 
73 uint16_t little_endian_read_16(const uint8_t * buffer, int pos){
74     return ((uint16_t) buffer[pos]) | (((uint16_t)buffer[(pos)+1]) << 8);
75 }
76 uint32_t little_endian_read_24(const uint8_t * buffer, int pos){
77     return ((uint32_t) buffer[pos]) | (((uint32_t)buffer[(pos)+1]) << 8) | (((uint32_t)buffer[(pos)+2]) << 16);
78 }
79 uint32_t little_endian_read_32(const uint8_t * buffer, int pos){
80     return ((uint32_t) buffer[pos]) | (((uint32_t)buffer[(pos)+1]) << 8) | (((uint32_t)buffer[(pos)+2]) << 16) | (((uint32_t) buffer[(pos)+3]) << 24);
81 }
82 
83 void little_endian_store_16(uint8_t *buffer, uint16_t pos, uint16_t value){
84     buffer[pos++] = value;
85     buffer[pos++] = value >> 8;
86 }
87 
88 void little_endian_store_32(uint8_t *buffer, uint16_t pos, uint32_t value){
89     buffer[pos++] = value;
90     buffer[pos++] = value >> 8;
91     buffer[pos++] = value >> 16;
92     buffer[pos++] = value >> 24;
93 }
94 
95 uint32_t big_endian_read_16( const uint8_t * buffer, int pos) {
96     return ((uint16_t) buffer[(pos)+1]) | (((uint16_t)buffer[ pos   ]) << 8);
97 }
98 
99 uint32_t big_endian_read_32( const uint8_t * buffer, int pos) {
100     return ((uint32_t) buffer[(pos)+3]) | (((uint32_t)buffer[(pos)+2]) << 8) | (((uint32_t)buffer[(pos)+1]) << 16) | (((uint32_t) buffer[pos]) << 24);
101 }
102 
103 void big_endian_store_16(uint8_t *buffer, uint16_t pos, uint16_t value){
104     buffer[pos++] = value >> 8;
105     buffer[pos++] = value;
106 }
107 
108 void big_endian_store_32(uint8_t *buffer, uint16_t pos, uint32_t value){
109     buffer[pos++] = value >> 24;
110     buffer[pos++] = value >> 16;
111     buffer[pos++] = value >> 8;
112     buffer[pos++] = value;
113 }
114 
115 // general swap/endianess utils
116 void reverse_bytes(const uint8_t *src, uint8_t *dst, int len){
117     int i;
118     for (i = 0; i < len; i++)
119         dst[len - 1 - i] = src[i];
120 }
121 void reverse_24(const uint8_t * src, uint8_t * dst){
122     reverse_bytes(src, dst, 3);
123 }
124 void reverse_48(const uint8_t * src, uint8_t * dst){
125     reverse_bytes(src, dst, 6);
126 }
127 void reverse_56(const uint8_t * src, uint8_t * dst){
128     reverse_bytes(src, dst, 7);
129 }
130 void reverse_64(const uint8_t * src, uint8_t * dst){
131     reverse_bytes(src, dst, 8);
132 }
133 void reverse_128(const uint8_t * src, uint8_t * dst){
134     reverse_bytes(src, dst, 16);
135 }
136 void reverse_256(const uint8_t * src, uint8_t * dst){
137     reverse_bytes(src, dst, 32);
138 }
139 
140 void reverse_bd_addr(const bd_addr_t src, bd_addr_t dest){
141     reverse_bytes(src, dest, 6);
142 }
143 
144 uint32_t btstack_min(uint32_t a, uint32_t b){
145     return a < b ? a : b;
146 }
147 
148 uint32_t btstack_max(uint32_t a, uint32_t b){
149     return a > b ? a : b;
150 }
151 
152 char char_for_nibble(int nibble){
153     if (nibble < 10) return '0' + nibble;
154     nibble -= 10;
155     if (nibble < 6) return 'A' + nibble;
156     return '?';
157 }
158 
159 int nibble_for_char(char c){
160     if (c >= '0' && c <= '9') return c - '0';
161     if (c >= 'a' && c <= 'f') return c - 'a' + 10;
162     if (c >= 'A' && c <= 'F') return c - 'A' + 10;
163     return -1;
164 }
165 
166 void printf_hexdump(const void *data, int size){
167     if (size <= 0) return;
168     int i;
169     for (i=0; i<size;i++){
170         printf("%02X ", ((uint8_t *)data)[i]);
171     }
172     printf("\n");
173 }
174 
175 void log_info_hexdump(const void *data, int size){
176 #ifdef ENABLE_LOG_INFO
177 
178     const int items_per_line = 16;
179     const int bytes_per_byte = 6;   // strlen('0x12, ')
180     const uint8_t low = 0x0F;
181     const uint8_t high = 0xF0;
182 
183     char buffer[bytes_per_byte*items_per_line+1];
184     int i, j;
185     j = 0;
186     for (i=0; i<size;i++){
187 
188         // help static analyzer proof that j stays within bounds
189         if (j > bytes_per_byte * (items_per_line-1)){
190             j = 0;
191         }
192 
193         uint8_t byte = ((uint8_t *)data)[i];
194         buffer[j++] = '0';
195         buffer[j++] = 'x';
196         buffer[j++] = char_for_nibble((byte & high) >> 4);
197         buffer[j++] = char_for_nibble(byte & low);
198         buffer[j++] = ',';
199         buffer[j++] = ' ';
200 
201         if (j >= bytes_per_byte * items_per_line ){
202             buffer[j] = 0;
203             log_info("%s", buffer);
204             j = 0;
205         }
206     }
207     if (j != 0){
208         buffer[j] = 0;
209         log_info("%s", buffer);
210     }
211 #endif
212 }
213 
214 void log_info_key(const char * name, sm_key_t key){
215 #ifdef ENABLE_LOG_INFO
216     char buffer[16*2+1];
217     const uint8_t low = 0x0F;
218     const uint8_t high = 0xF0;
219     int i;
220     int j = 0;
221     for (i=0; i<16;i++){
222         uint8_t byte = key[i];
223         buffer[j++] = char_for_nibble((byte & high) >> 4);
224         buffer[j++] = char_for_nibble(byte & low);
225     }
226     buffer[j] = 0;
227     log_info("%-6s %s", name, buffer);
228 #endif
229 }
230 
231 // UUIDs are stored in big endian, similar to bd_addr_t
232 
233 // Bluetooth Base UUID: 00000000-0000-1000-8000- 00805F9B34FB
234 const uint8_t bluetooth_base_uuid[] = { 0x00, 0x00, 0x00, 0x00, /* - */ 0x00, 0x00, /* - */ 0x10, 0x00, /* - */
235     0x80, 0x00, /* - */ 0x00, 0x80, 0x5F, 0x9B, 0x34, 0xFB };
236 
237 void uuid_add_bluetooth_prefix(uint8_t *uuid, uint32_t shortUUID){
238     memcpy(uuid, bluetooth_base_uuid, 16);
239     big_endian_store_32(uuid, 0, shortUUID);
240 }
241 
242 int uuid_has_bluetooth_prefix(uint8_t * uuid128){
243     return memcmp(&uuid128[4], &bluetooth_base_uuid[4], 12) == 0;
244 }
245 
246 static char uuid128_to_str_buffer[32+4+1];
247 char * uuid128_to_str(uint8_t * uuid){
248     int i;
249     int j = 0;
250     const uint8_t low =  0x0F;
251     const uint8_t high = 0xF0;
252     // after 4, 6, 8, and 10 bytes = XYXYXYXY-XYXY-XYXY-XYXY-XYXYXYXYXYXY, there's a dash
253     const int dash_locations = (1<<3) | (1<<5) | (1<<7) | (1<<9);
254     for (i=0;i<16;i++){
255         uuid128_to_str_buffer[j++] = char_for_nibble((uuid[i] & high) >> 4);
256         uuid128_to_str_buffer[j++] = char_for_nibble(uuid[i] & low);
257         if (dash_locations & (1<<i)){
258             uuid128_to_str_buffer[j++] = '-';
259         }
260     }
261     return uuid128_to_str_buffer;
262 }
263 
264 static char bd_addr_to_str_buffer[6*3];  // 12:45:78:01:34:67\0
265 char * bd_addr_to_str(bd_addr_t addr){
266     // orig code
267     // sprintf(bd_addr_to_str_buffer, "%02x:%02x:%02x:%02x:%02x:%02x", addr[0], addr[1], addr[2], addr[3], addr[4], addr[5]);
268     // sprintf-free code
269     char * p = bd_addr_to_str_buffer;
270     int i;
271     for (i = 0; i < 6 ; i++) {
272         *p++ = char_for_nibble((addr[i] >> 4) & 0x0F);
273         *p++ = char_for_nibble((addr[i] >> 0) & 0x0F);
274         *p++ = ':';
275     }
276     *--p = 0;
277     return (char *) bd_addr_to_str_buffer;
278 }
279 
280 static int scan_hex_byte(const char * byte_string){
281     int upper_nibble = nibble_for_char(*byte_string++);
282     if (upper_nibble < 0) return -1;
283     int lower_nibble = nibble_for_char(*byte_string);
284     if (lower_nibble < 0) return -1;
285     return (upper_nibble << 4) | lower_nibble;
286 }
287 
288 int sscanf_bd_addr(const char * addr_string, bd_addr_t addr){
289     uint8_t buffer[BD_ADDR_LEN];
290     int result = 0;
291     int i;
292     for (i = 0; i < BD_ADDR_LEN; i++) {
293         int single_byte = scan_hex_byte(addr_string);
294         if (single_byte < 0) break;
295         addr_string += 2;
296         buffer[i] = single_byte;
297         // don't check seperator after last byte
298         if (i == BD_ADDR_LEN - 1) {
299             result = 1;
300             break;
301         }
302         char separator = *addr_string++;
303         if (separator != ':' && separator != '-' && separator != ' ') break;
304     }
305 
306     if (result){
307         bd_addr_copy(addr, buffer);
308     }
309 	return result;
310 }
311