xref: /aosp_15_r20/external/mesa3d/src/util/hex.h (revision 6104692788411f58d303aa86923a9ff6ecaded22)
1 /* Copyright © 2023 Valve Corporation
2  *
3  * Permission is hereby granted, free of charge, to any person obtaining a
4  * copy of this software and associated documentation files (the "Software"),
5  * to deal in the Software without restriction, including without limitation
6  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
7  * and/or sell copies of the Software, and to permit persons to whom the
8  * Software is furnished to do so, subject to the following conditions:
9  *
10  * The above copyright notice and this permission notice (including the next
11  * paragraph) shall be included in all copies or substantial portions of the
12  * Software.
13  *
14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
17  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
18  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
19  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
20  * DEALINGS IN THE SOFTWARE.
21  */
22 
23 #ifndef UTIL_HEX_H
24 #define UTIL_HEX_H
25 
26 #ifdef __cplusplus
27 extern "C" {
28 #endif
29 
30 /*
31  * Convert a binary buffer of length `len` to a hexadecimal string of length
32  * `len * 2 + 1` (including NUL terminator).
33  */
mesa_bytes_to_hex(char * buf,const unsigned char * binary,unsigned len)34 static inline char *mesa_bytes_to_hex(char *buf, const unsigned char *binary,
35                                       unsigned len) {
36   static const char hex_digits[] = "0123456789abcdef";
37   unsigned i;
38 
39   for (i = 0; i < len * 2; i += 2) {
40     buf[i] = hex_digits[binary[i >> 1] >> 4];
41     buf[i + 1] = hex_digits[binary[i >> 1] & 0x0f];
42   }
43   buf[i] = '\0';
44 
45   return buf;
46 }
47 
_mesa_hex_to_int(unsigned char c)48 static inline int _mesa_hex_to_int(unsigned char c)
49 {
50   return c - (c >= 'a' ? 'a' - 10 : '0');
51 }
52 
53 /*
54  * Read `len` pairs of hexadecimal digits from `hex` and write the values to
55  * `binary` as `len` bytes.
56  * Hexadecimals must be lower case.
57  */
mesa_hex_to_bytes(unsigned char * buf,const char * hex,unsigned len)58 static inline void mesa_hex_to_bytes(unsigned char *buf, const char *hex,
59                                      unsigned len)
60 {
61   for (unsigned i = 0; i < len; i++) {
62     int hi = _mesa_hex_to_int(hex[i * 2]);
63     int lo = _mesa_hex_to_int(hex[i * 2 + 1]);
64 
65     buf[i] = (hi << 4) | lo;
66   }
67 }
68 
69 #ifdef __cplusplus
70 }
71 #endif
72 
73 #endif
74