mirror of
https://github.com/morgan9e/systemd
synced 2026-04-14 08:25:20 +09:00
38 lines
2.0 KiB
C
38 lines
2.0 KiB
C
/* SPDX-License-Identifier: LGPL-2.1-or-later */
|
|
#pragma once
|
|
|
|
#include <pthread.h>
|
|
|
|
#include "process-util.h"
|
|
#include "random-util.h"
|
|
|
|
/* This pattern needs to be repeated exactly in multiple modules, so macro it.
|
|
* To ensure an object is not passed into a different module (e.g.: when two shared objects statically
|
|
* linked to libsystemd get loaded in the same process, and the object created by one is passed to the
|
|
* other, see https://github.com/systemd/systemd/issues/27216), create a random static global random
|
|
* (mixed with PID, so that we can also check for reuse after fork) that is stored in the object and
|
|
* checked by public API on use. */
|
|
#define _DEFINE_ORIGIN_ID_HELPERS(type, name, scope) \
|
|
static uint64_t origin_id; \
|
|
\
|
|
static void origin_id_initialize(void) { \
|
|
origin_id = random_u64(); \
|
|
} \
|
|
\
|
|
static uint64_t origin_id_query(void) { \
|
|
static pthread_once_t once = PTHREAD_ONCE_INIT; \
|
|
assert_se(pthread_once(&once, origin_id_initialize) == 0); \
|
|
return origin_id ^ getpid_cached(); \
|
|
} \
|
|
\
|
|
scope bool name##_origin_changed(type *p) { \
|
|
assert(p); \
|
|
return p->origin_id != origin_id_query(); \
|
|
}
|
|
|
|
#define DEFINE_ORIGIN_ID_HELPERS(type, name) \
|
|
_DEFINE_ORIGIN_ID_HELPERS(type, name,);
|
|
|
|
#define DEFINE_PRIVATE_ORIGIN_ID_HELPERS(type, name) \
|
|
_DEFINE_ORIGIN_ID_HELPERS(type, name, static);
|