ladybird/Kernel/ProcessGroup.cpp
AnotherTest 688e54eac7 Kernel: Distinguish between new and old process groups with equal pgids
This does not add any behaviour change to the processes, but it ties a
TTY to an active process group via TIOCSPGRP, and returns the TTY to the
kernel when all processes in the process group die.
Also makes the TTY keep a link to the original controlling process' parent (for
SIGCHLD) instead of the process itself.
2020-08-19 21:21:34 +02:00

70 lines
2.3 KiB
C++

/*
* Copyright (c) 2020, the SerenityOS developers.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "ProcessGroup.h"
namespace Kernel {
RecursiveSpinLock g_process_groups_lock;
InlineLinkedList<ProcessGroup>* g_process_groups;
ProcessGroup::~ProcessGroup()
{
ScopedSpinLock lock(g_process_groups_lock);
g_process_groups->remove(this);
}
NonnullRefPtr<ProcessGroup> ProcessGroup::create(ProcessGroupID pgid)
{
auto process_group = adopt(*new ProcessGroup(pgid));
{
ScopedSpinLock lock(g_process_groups_lock);
g_process_groups->prepend(process_group);
}
return process_group;
}
NonnullRefPtr<ProcessGroup> ProcessGroup::find_or_create(ProcessGroupID pgid)
{
if (auto existing = from_pgid(pgid))
return *existing;
return create(pgid);
}
ProcessGroup* ProcessGroup::from_pgid(ProcessGroupID pgid)
{
ScopedSpinLock lock(g_process_groups_lock);
for (auto& group : *g_process_groups) {
if (group.pgid() == pgid)
return &group;
}
return nullptr;
}
}