Campbell Barton
c434782e3a
Use a shorter/simpler license convention, stops the header taking so much space. Follow the SPDX license specification: https://spdx.org/licenses - C/C++/objc/objc++ - Python - Shell Scripts - CMake, GNUmakefile While most of the source tree has been included - `./extern/` was left out. - `./intern/cycles` & `./intern/atomic` are also excluded because they use different header conventions. doc/license/SPDX-license-identifiers.txt has been added to list SPDX all used identifiers. See P2788 for the script that automated these edits. Reviewed By: brecht, mont29, sergey Ref D14069
65 lines
1.8 KiB
C
65 lines
1.8 KiB
C
/* SPDX-License-Identifier: GPL-2.0-or-later */
|
|
|
|
/** \file
|
|
* \ingroup bli
|
|
*/
|
|
|
|
#include "BLI_session_uuid.h"
|
|
|
|
#include "BLI_utildefines.h"
|
|
|
|
#include "atomic_ops.h"
|
|
|
|
/* Special value which indicates the UUID has not been assigned yet. */
|
|
#define BLI_SESSION_UUID_NONE 0
|
|
|
|
static const SessionUUID global_session_uuid_none = {BLI_SESSION_UUID_NONE};
|
|
|
|
/* Denotes last used UUID.
|
|
* It might eventually overflow, and easiest is to add more bits to it. */
|
|
static SessionUUID global_session_uuid = {BLI_SESSION_UUID_NONE};
|
|
|
|
SessionUUID BLI_session_uuid_generate(void)
|
|
{
|
|
SessionUUID result;
|
|
result.uuid_ = atomic_add_and_fetch_uint64(&global_session_uuid.uuid_, 1);
|
|
if (!BLI_session_uuid_is_generated(&result)) {
|
|
/* Happens when the UUID overflows.
|
|
*
|
|
* Just request the UUID once again, hoping that there are not a lot of high-priority threads
|
|
* which will overflow the counter once again between the previous call and this one.
|
|
*
|
|
* NOTE: It is possible to have collisions after such overflow. */
|
|
result.uuid_ = atomic_add_and_fetch_uint64(&global_session_uuid.uuid_, 1);
|
|
}
|
|
return result;
|
|
}
|
|
|
|
bool BLI_session_uuid_is_generated(const SessionUUID *uuid)
|
|
{
|
|
return !BLI_session_uuid_is_equal(uuid, &global_session_uuid_none);
|
|
}
|
|
|
|
bool BLI_session_uuid_is_equal(const SessionUUID *lhs, const SessionUUID *rhs)
|
|
{
|
|
return lhs->uuid_ == rhs->uuid_;
|
|
}
|
|
|
|
uint64_t BLI_session_uuid_hash_uint64(const SessionUUID *uuid)
|
|
{
|
|
return uuid->uuid_;
|
|
}
|
|
|
|
uint BLI_session_uuid_ghash_hash(const void *uuid_v)
|
|
{
|
|
const SessionUUID *uuid = (const SessionUUID *)uuid_v;
|
|
return uuid->uuid_ & 0xffffffff;
|
|
}
|
|
|
|
bool BLI_session_uuid_ghash_compare(const void *lhs_v, const void *rhs_v)
|
|
{
|
|
const SessionUUID *lhs = (const SessionUUID *)lhs_v;
|
|
const SessionUUID *rhs = (const SessionUUID *)rhs_v;
|
|
return !BLI_session_uuid_is_equal(lhs, rhs);
|
|
}
|