1/*
2 * Copyright (C) 2017 Igalia S.L.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 *
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
15 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
16 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
17 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
18 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
19 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
20 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
21 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#include "config.h"
27#include "FileMonitor.h"
28
29#include <wtf/FileSystem.h>
30#include <wtf/glib/GUniquePtr.h>
31#include <wtf/threads/BinarySemaphore.h>
32
33namespace WebCore {
34
35FileMonitor::FileMonitor(const String& path, Ref<WorkQueue>&& handlerQueue, WTF::Function<void(FileChangeType)>&& modificationHandler)
36 : m_handlerQueue(WTFMove(handlerQueue))
37 , m_modificationHandler(WTFMove(modificationHandler))
38{
39 if (path.isEmpty() || !m_modificationHandler)
40 return;
41
42 Function<void ()> createPlatformMonitor = [&] {
43 auto file = adoptGRef(g_file_new_for_path(FileSystem::fileSystemRepresentation(path).data()));
44 GUniqueOutPtr<GError> error;
45 m_platformMonitor = adoptGRef(g_file_monitor(file.get(), G_FILE_MONITOR_NONE, nullptr, &error.outPtr()));
46 if (m_platformMonitor)
47 g_signal_connect(m_platformMonitor.get(), "changed", G_CALLBACK(fileChangedCallback), this);
48 else
49 WTFLogAlways("Failed to create a monitor for path %s: %s", path.utf8().data(), error->message);
50 };
51
52 // The monitor can be created in the work queue thread.
53 if (&m_handlerQueue->runLoop() == &RunLoop::current()) {
54 createPlatformMonitor();
55 return;
56 }
57
58 BinarySemaphore semaphore;
59 m_handlerQueue->dispatch([createPlatformMonitor = WTFMove(createPlatformMonitor), &semaphore] {
60 createPlatformMonitor();
61 semaphore.signal();
62 });
63 semaphore.wait();
64}
65
66FileMonitor::~FileMonitor()
67{
68 // The monitor can be destroyed in the work queue thread.
69 if (&m_handlerQueue->runLoop() == &RunLoop::current())
70 return;
71
72 BinarySemaphore semaphore;
73 m_handlerQueue->dispatch([&] {
74 m_platformMonitor = nullptr;
75 semaphore.signal();
76 });
77 semaphore.wait();
78}
79
80void FileMonitor::fileChangedCallback(GFileMonitor*, GFile*, GFile*, GFileMonitorEvent event, FileMonitor* monitor)
81{
82 switch (event) {
83 case G_FILE_MONITOR_EVENT_DELETED:
84 monitor->didChange(FileChangeType::Removal);
85 break;
86 case G_FILE_MONITOR_EVENT_CHANGES_DONE_HINT:
87 case G_FILE_MONITOR_EVENT_CREATED:
88 monitor->didChange(FileChangeType::Modification);
89 break;
90 default:
91 break;
92 }
93}
94
95void FileMonitor::didChange(FileChangeType type)
96{
97 ASSERT(!isMainThread());
98 if (type == FileChangeType::Removal)
99 m_platformMonitor = nullptr;
100 m_modificationHandler(type);
101}
102
103} // namespace WebCore
104