uuid.h (4895B)
1 /* 2 * Copyright (c) 2022 Pierre-Anthony Lemieux <pal@palemieux.com> 3 * Zane van Iperen <zane@zanevaniperen.com> 4 * 5 * This file is part of FFmpeg. 6 * 7 * FFmpeg is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU Lesser General Public 9 * License as published by the Free Software Foundation; either 10 * version 2.1 of the License, or (at your option) any later version. 11 * 12 * FFmpeg is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 * Lesser General Public License for more details. 16 * 17 * You should have received a copy of the GNU Lesser General Public 18 * License along with FFmpeg; if not, write to the Free Software 19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 20 */ 21 22 /** 23 * @file 24 * UUID parsing and serialization utilities. 25 * The library treats the UUID as an opaque sequence of 16 unsigned bytes, 26 * i.e. ignoring the internal layout of the UUID, which depends on the type 27 * of the UUID. 28 * 29 * @author Pierre-Anthony Lemieux <pal@palemieux.com> 30 * @author Zane van Iperen <zane@zanevaniperen.com> 31 */ 32 33 #ifndef AVUTIL_UUID_H 34 #define AVUTIL_UUID_H 35 36 #include <stdint.h> 37 #include <string.h> 38 39 #define AV_PRI_UUID \ 40 "%02hhx%02hhx%02hhx%02hhx-%02hhx%02hhx-" \ 41 "%02hhx%02hhx-%02hhx%02hhx-%02hhx%02hhx%02hhx%02hhx%02hhx%02hhx" 42 43 #define AV_PRI_URN_UUID \ 44 "urn:uuid:%02hhx%02hhx%02hhx%02hhx-%02hhx%02hhx-" \ 45 "%02hhx%02hhx-%02hhx%02hhx-%02hhx%02hhx%02hhx%02hhx%02hhx%02hhx" 46 47 /* AV_UUID_ARG() is used together with AV_PRI_UUID() or AV_PRI_URN_UUID 48 * to print UUIDs, e.g. 49 * av_log(NULL, AV_LOG_DEBUG, "UUID: " AV_PRI_UUID, AV_UUID_ARG(uuid)); 50 */ 51 #define AV_UUID_ARG(x) \ 52 (x)[ 0], (x)[ 1], (x)[ 2], (x)[ 3], \ 53 (x)[ 4], (x)[ 5], (x)[ 6], (x)[ 7], \ 54 (x)[ 8], (x)[ 9], (x)[10], (x)[11], \ 55 (x)[12], (x)[13], (x)[14], (x)[15] 56 57 #define AV_UUID_LEN 16 58 59 /* Binary representation of a UUID */ 60 typedef uint8_t AVUUID[AV_UUID_LEN]; 61 62 /** 63 * Parses a string representation of a UUID formatted according to IETF RFC 4122 64 * into an AVUUID. The parsing is case-insensitive. The string must be 37 65 * characters long, including the terminating NUL character. 66 * 67 * Example string representation: "2fceebd0-7017-433d-bafb-d073a7116696" 68 * 69 * @param[in] in String representation of a UUID, 70 * e.g. 2fceebd0-7017-433d-bafb-d073a7116696 71 * @param[out] uu AVUUID 72 * @return A non-zero value in case of an error. 73 */ 74 int av_uuid_parse(const char *in, AVUUID uu); 75 76 /** 77 * Parses a URN representation of a UUID, as specified at IETF RFC 4122, 78 * into an AVUUID. The parsing is case-insensitive. The string must be 46 79 * characters long, including the terminating NUL character. 80 * 81 * Example string representation: "urn:uuid:2fceebd0-7017-433d-bafb-d073a7116696" 82 * 83 * @param[in] in URN UUID 84 * @param[out] uu AVUUID 85 * @return A non-zero value in case of an error. 86 */ 87 int av_uuid_urn_parse(const char *in, AVUUID uu); 88 89 /** 90 * Parses a string representation of a UUID formatted according to IETF RFC 4122 91 * into an AVUUID. The parsing is case-insensitive. 92 * 93 * @param[in] in_start Pointer to the first character of the string representation 94 * @param[in] in_end Pointer to the character after the last character of the 95 * string representation. That memory location is never 96 * accessed. It is an error if `in_end - in_start != 36`. 97 * @param[out] uu AVUUID 98 * @return A non-zero value in case of an error. 99 */ 100 int av_uuid_parse_range(const char *in_start, const char *in_end, AVUUID uu); 101 102 /** 103 * Serializes a AVUUID into a string representation according to IETF RFC 4122. 104 * The string is lowercase and always 37 characters long, including the 105 * terminating NUL character. 106 * 107 * @param[in] uu AVUUID 108 * @param[out] out Pointer to an array of no less than 37 characters. 109 */ 110 void av_uuid_unparse(const AVUUID uu, char *out); 111 112 /** 113 * Compares two UUIDs for equality. 114 * 115 * @param[in] uu1 AVUUID 116 * @param[in] uu2 AVUUID 117 * @return Nonzero if uu1 and uu2 are identical, 0 otherwise 118 */ 119 static inline int av_uuid_equal(const AVUUID uu1, const AVUUID uu2) 120 { 121 return memcmp(uu1, uu2, AV_UUID_LEN) == 0; 122 } 123 124 /** 125 * Copies the bytes of src into dest. 126 * 127 * @param[out] dest AVUUID 128 * @param[in] src AVUUID 129 */ 130 static inline void av_uuid_copy(AVUUID dest, const AVUUID src) 131 { 132 memcpy(dest, src, AV_UUID_LEN); 133 } 134 135 /** 136 * Sets a UUID to the nil UUID, i.e. a UUID with have all 137 * its 128 bits set to zero. 138 * 139 * @param[in,out] uu UUID to be set to the nil UUID 140 */ 141 static inline void av_uuid_nil(AVUUID uu) 142 { 143 memset(uu, 0, AV_UUID_LEN); 144 } 145 146 #endif /* AVUTIL_UUID_H */