llvm/clang/lib/DirectoryWatcher/linux/DirectoryWatcher-linux.cpp

//===- DirectoryWatcher-linux.cpp - Linux-platform directory watching -----===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//

#include "DirectoryScanner.h"
#include "clang/DirectoryWatcher/DirectoryWatcher.h"

#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/ScopeExit.h"
#include "llvm/Support/AlignOf.h"
#include "llvm/Support/Errno.h"
#include "llvm/Support/Error.h"
#include "llvm/Support/Path.h"
#include <atomic>
#include <condition_variable>
#include <mutex>
#include <queue>
#include <string>
#include <thread>
#include <vector>

#include <fcntl.h>
#include <limits.h>
#include <optional>
#include <sys/epoll.h>
#include <sys/inotify.h>
#include <unistd.h>

namespace {

usingnamespacellvm;
usingnamespaceclang;

/// Pipe for inter-thread synchronization - for epoll-ing on multiple
/// conditions. It is meant for uni-directional 1:1 signalling - specifically:
/// no multiple consumers, no data passing. Thread waiting for signal should
/// poll the FDRead. Signalling thread should call signal() which writes single
/// character to FDRead.
struct SemaphorePipe { … };

/// Mutex-protected queue of Events.
class EventQueue { … };

class DirectoryWatcherLinux : public clang::DirectoryWatcher { … };

void DirectoryWatcherLinux::InotifyPollingLoop() { … }

void DirectoryWatcherLinux::InitialScan() { … }

void DirectoryWatcherLinux::EventReceivingLoop() { … }

DirectoryWatcherLinux::DirectoryWatcherLinux(
    StringRef WatchedDirPath,
    std::function<void(llvm::ArrayRef<Event>, bool)> Receiver,
    bool WaitForInitialSync, int InotifyFD, int InotifyWD,
    SemaphorePipe &&InotifyPollingStopSignal)
    : … { … }

} // namespace

llvm::Expected<std::unique_ptr<DirectoryWatcher>> clang::DirectoryWatcher::create(
    StringRef Path,
    std::function<void(llvm::ArrayRef<DirectoryWatcher::Event>, bool)> Receiver,
    bool WaitForInitialSync) { … }