RGBCube/serenity
1
Fork 0
mirror of https://github.com/RGBCube/serenity synced 2025-05-28 08:25:07 +00:00
Code Issues Activity Actions

Kernel+LibPthread: Implement pthread_join()

Browse source 
It's now possible to block until another thread in the same process has
exited. We can also retrieve its exit value, which is whatever value it
passed to pthread_exit(). :^)
This commit is contained in:
Andreas Kling 2019-11-14 20:58:23 +01:00
parent c6a8b95643
commit 69efa3f630
9 changed files with 117 additions and 5 deletions
Download patch file Download diff file Expand all files Collapse all files

45
Kernel/Process.cpp
View file

@ -2862,9 +2862,9 @@ int Process::sys$create_thread(void* (*entry)(void*), void* argument)
return thread->tid();
}
void Process::sys$exit_thread(void* code)
void Process::sys$exit_thread(void* exit_value)
{
UNUSED_PARAM(code);
current->m_exit_value = exit_value;
cli();
if (&current->process().main_thread() == current) {
// FIXME: For POSIXy reasons, we should only sys$exit once *all* threads have exited.
@ -2877,6 +2877,47 @@ void Process::sys$exit_thread(void* code)
ASSERT_NOT_REACHED();
}
int Process::sys$join_thread(int tid, void** exit_value)
{
if (exit_value && !validate_write_typed(exit_value))
return -EFAULT;
Thread* thread = nullptr;
for_each_thread([&](auto& child_thread) {
if (child_thread.tid() == tid) {
thread = &child_thread;
return IterationDecision::Break;
}
return IterationDecision::Continue;
});
if (!thread)
return -ESRCH;
if (thread == current)
return -EDEADLK;
if (thread->m_joinee == current)
return -EDEADLK;
ASSERT(thread->m_joiner != current);
if (thread->m_joiner)
return -EINVAL;
// FIXME: EINVAL: 'thread' is not a joinable thread
// FIXME: pthread_join() should not be interruptable. Enforce this somehow?
auto result = current->block<Thread::JoinBlocker>(*thread);
(void)result;
// NOTE: 'thread' is very possibly deleted at this point. Clear it just to be safe.
thread = nullptr;
if (exit_value)
*exit_value = current->m_joinee_exit_value;
return 0;
}
int Process::sys$gettid()
{
return current->tid();