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/* SPDX-License-Identifier: LGPL-2.1-or-later */
#pragma once
#include <sys/types.h>
#include "macro.h"
#include "rm-rf.h"
/* These functions implement various potentially slow operations that are executed asynchronously. They are
* carefully written to not use pthreads, but use fork() or clone() (without CLONE_VM) so that the child does
* not share any memory with the parent process, and thus cannot possibly interfere with the malloc()
* synchronization locks.
*
* Background: glibc only synchronizes malloc() locks when doing fork(), but not when doing clone()
* (regardless if through glibc's own wrapper or ours). This means if another thread in the parent has the
* malloc() lock taken while a thread is cloning, the mutex will remain locked in the child (but the other
* thread won't exist there), with no chance to ever be unlocked again. This will result in deadlocks. Hence
* one has to make the choice: either never use threads in the parent, or never do memory allocation in the
* child, or never use clone()/clone3() and stick to fork() only. Because we need clone()/clone3() we opted
* for avoiding threads. */
int asynchronous_sync(pid_t *ret_pid);
int asynchronous_close(int fd);
int asynchronous_rm_rf(const char *p, RemoveFlags flags);
DEFINE_TRIVIAL_CLEANUP_FUNC(int, asynchronous_close);
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