ffmpeg/libavutil/uuid.h

148 lines
4.8 KiB
C

/*
* Copyright (c) 2022 Pierre-Anthony Lemieux <pal@palemieux.com>
* Zane van Iperen <zane@zanevaniperen.com>
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* UUID parsing and serialization utilities.
* The library treats the UUID as an opaque sequence of 16 unsigned bytes,
* i.e. ignoring the internal layout of the UUID, which depends on the type
* of the UUID.
*
* @author Pierre-Anthony Lemieux <pal@palemieux.com>
* @author Zane van Iperen <zane@zanevaniperen.com>
*/
#ifndef AVUTIL_UUID_H
#define AVUTIL_UUID_H
#include <stdint.h>
#include <string.h>
#define AV_PRI_UUID \
"%02hhx%02hhx%02hhx%02hhx-%02hhx%02hhx-" \
"%02hhx%02hhx-%02hhx%02hhx-%02hhx%02hhx%02hhx%02hhx%02hhx%02hhx"
#define AV_PRI_URN_UUID \
"urn:uuid:%02hhx%02hhx%02hhx%02hhx-%02hhx%02hhx-" \
"%02hhx%02hhx-%02hhx%02hhx-%02hhx%02hhx%02hhx%02hhx%02hhx%02hhx"
/* AV_UUID_ARG() is used together with AV_PRI_UUID() or AV_PRI_URN_UUID
* to print UUIDs, e.g.
* av_log(NULL, AV_LOG_DEBUG, "UUID: " AV_PRI_UUID, AV_UUID_ARG(uuid));
*/
#define AV_UUID_ARG(x) \
(x)[ 0], (x)[ 1], (x)[ 2], (x)[ 3], \
(x)[ 4], (x)[ 5], (x)[ 6], (x)[ 7], \
(x)[ 8], (x)[ 9], (x)[10], (x)[11], \
(x)[12], (x)[13], (x)[14], (x)[15]
#define AV_UUID_LEN 16
/* Binary representation of a UUID */
typedef uint8_t AVUUID[AV_UUID_LEN];
/**
* Parses a string representation of a UUID formatted according to IETF RFC 4122
* into an AVUUID. The parsing is case-insensitive. The string must be 37
* characters long, including the terminating NUL character.
*
* Example string representation: "2fceebd0-7017-433d-bafb-d073a7116696"
*
* @param[in] in String representation of a UUID,
* e.g. 2fceebd0-7017-433d-bafb-d073a7116696
* @param[out] uu AVUUID
* @return A non-zero value in case of an error.
*/
int av_uuid_parse(const char *in, AVUUID uu);
/**
* Parses a URN representation of a UUID, as specified at IETF RFC 4122,
* into an AVUUID. The parsing is case-insensitive. The string must be 46
* characters long, including the terminating NUL character.
*
* Example string representation: "urn:uuid:2fceebd0-7017-433d-bafb-d073a7116696"
*
* @param[in] in URN UUID
* @param[out] uu AVUUID
* @return A non-zero value in case of an error.
*/
int av_uuid_urn_parse(const char *in, AVUUID uu);
/**
* Parses a string representation of a UUID formatted according to IETF RFC 4122
* into an AVUUID. The parsing is case-insensitive.
*
* @param[in] in_start Pointer to the first character of the string representation
* @param[in] in_end Pointer to the character after the last character of the
* string representation. That memory location is never
* accessed. It is an error if `in_end - in_start != 36`.
* @param[out] uu AVUUID
* @return A non-zero value in case of an error.
*/
int av_uuid_parse_range(const char *in_start, const char *in_end, AVUUID uu);
/**
* Serializes a AVUUID into a string representation according to IETF RFC 4122.
* The string is lowercase and always 37 characters long, including the
* terminating NUL character.
*
* @param[in] uu AVUUID
* @param[out] out Pointer to an array of no less than 37 characters.
* @return A non-zero value in case of an error.
*/
void av_uuid_unparse(const AVUUID uu, char *out);
/**
* Compares two UUIDs for equality.
*
* @param[in] uu1 AVUUID
* @param[in] uu2 AVUUID
* @return Nonzero if uu1 and uu2 are identical, 0 otherwise
*/
static inline int av_uuid_equal(const AVUUID uu1, const AVUUID uu2)
{
return memcmp(uu1, uu2, AV_UUID_LEN) == 0;
}
/**
* Copies the bytes of src into dest.
*
* @param[out] dest AVUUID
* @param[in] src AVUUID
*/
static inline void av_uuid_copy(AVUUID dest, const AVUUID src)
{
memcpy(dest, src, AV_UUID_LEN);
}
/**
* Sets a UUID to the nil UUID, i.e. a UUID with have all
* its 128 bits set to zero.
*
* @param[in,out] uu UUID to be set to the nil UUID
*/
static inline void av_uuid_nil(AVUUID uu)
{
memset(uu, 0, AV_UUID_LEN);
}
#endif /* AVUTIL_UUID_H */