serenity/Kernel/Syscalls/fsync.cpp

/*
 * Copyright (c) 2021, the SerenityOS developers.
 *
 * SPDX-License-Identifier: BSD-2-Clause
 */

#include <Kernel/Tasks/Process.h>

namespace Kernel {

ErrorOr<FlatPtr> Process::sys$fsync(int fd)
{
    VERIFY_NO_PROCESS_BIG_LOCK(this);
    TRY(require_promise(Pledge::stdio));
    auto description = TRY(open_file_description(fd));
    TRY(description->sync());
    return 0;
}

}
Kernel+LibC: Implement fsync 2021-09-11 23:28:59 -04:00			`/*`
			`* Copyright (c) 2021, the SerenityOS developers.`
			`*`
			`* SPDX-License-Identifier: BSD-2-Clause`
			`*/`

Kernel: Move all tasks-related code to the Tasks subdirectory 2023-02-24 19:45:37 +02:00			`#include <Kernel/Tasks/Process.h>`
Kernel+LibC: Implement fsync 2021-09-11 23:28:59 -04:00
			`namespace Kernel {`

Kernel: Replace KResult and KResultOr<T> with Error and ErrorOr<T> We now use AK::Error and AK::ErrorOr<T> in both kernel and userspace! This was a slightly tedious refactoring that took a long time, so it's not unlikely that some bugs crept in. Nevertheless, it does pass basic functionality testing, and it's just real nice to finally see the same pattern in all contexts. :^) 2021-11-08 00:51:39 +01:00			`ErrorOr<FlatPtr> Process::sys$fsync(int fd)`
Kernel+LibC: Implement fsync 2021-09-11 23:28:59 -04:00			`{`
Kernel: Mark sys$fsync() as not needing the big lock This syscall doesn't access any data that was implicitly protected by the big lock. 2022-03-07 21:38:10 +01:00			`VERIFY_NO_PROCESS_BIG_LOCK(this);`
Kernel: Handle promise violations in the syscall handler Previously we would crash the process immediately when a promise violation was found during a syscall. This is error prone, as we don't unwind the stack. This means that in certain cases we can leak resources, like an OwnPtr / RefPtr tracked on the stack. Or even leak a lock acquired in a ScopeLockLocker. To remedy this situation we move the promise violation handling to the syscall handler, right before we return to user space. This allows the code to follow the normal unwind path, and grantees there is no longer any cleanup that needs to occur. The Process::require_promise() and Process::require_no_promises() functions were modified to return ErrorOr<void> so we enforce that the errors are always propagated by the caller. 2021-12-29 01:11:45 -08:00			`TRY(require_promise(Pledge::stdio));`
Kernel: Convert process file descriptor table to a SpinlockProtected Instead of manually locking in the various member functions of Process::OpenFileDescriptions, simply wrap it in a SpinlockProtected. 2022-01-29 01:22:28 +01:00			`auto description = TRY(open_file_description(fd));`
Kernel: Replace KResult and KResultOr<T> with Error and ErrorOr<T> We now use AK::Error and AK::ErrorOr<T> in both kernel and userspace! This was a slightly tedious refactoring that took a long time, so it's not unlikely that some bugs crept in. Nevertheless, it does pass basic functionality testing, and it's just real nice to finally see the same pattern in all contexts. :^) 2021-11-08 00:51:39 +01:00			`TRY(description->sync());`
			`return 0;`
Kernel+LibC: Implement fsync 2021-09-11 23:28:59 -04:00			`}`

			`}`