2 * \file FileMonitor.cpp
3 * This file is part of LyX, the document processor.
4 * Licence details can be found in the file COPYING.
6 * \author Guillaume Munch
8 * Full author contact details are available in file CREDITS.
13 #include "support/FileMonitor2.h"
15 #include "support/debug.h"
16 #include "support/FileName.h"
17 #include "support/qstring_helpers.h"
18 #include "support/unique_ptr.h"
21 #include <QSignalBlocker>
32 FileSystemWatcher & FileSystemWatcher::instance()
34 // This thread-safe because QFileSystemWatcher is thread-safe.
35 static FileSystemWatcher f;
40 FileSystemWatcher::FileSystemWatcher()
41 : qwatcher_(make_unique<QFileSystemWatcher>())
46 FileMonitorPtr FileSystemWatcher::monitor(FileName const & file_with_path)
48 FileSystemWatcher & f = instance();
49 string const filename = file_with_path.absFileName();
50 weak_ptr<FileMonitorGuard> & wptr = f.store_[filename];
51 if (shared_ptr<FileMonitorGuard> mon = wptr.lock())
52 return make_unique<FileMonitor2>(mon);
53 auto mon = make_shared<FileMonitorGuard>(filename, f.qwatcher_.get());
55 return make_unique<FileMonitor2>(mon);
60 void FileSystemWatcher::debug()
62 FileSystemWatcher & f = instance();
63 QStringList q_files = f.qwatcher_->files();
64 for (pair<string, weak_ptr<FileMonitorGuard>> pair : f.store_) {
65 string const & name = pair.first;
66 if (!pair.second.expired()) {
67 if (!q_files.contains(toqstr(name)))
68 LYXERR0("Monitored but not QFileSystemWatched (bad): " << name);
70 //LYXERR0("Monitored and QFileSystemWatched (good): " << name);
74 for (QString const & qname : q_files) {
75 string const name = fromqstr(qname);
76 weak_ptr<FileMonitorGuard> & wptr = f.store_[name];
78 LYXERR0("QFileSystemWatched but not monitored (bad): " << name);
83 FileMonitorGuard::FileMonitorGuard(string const & filename,
84 QFileSystemWatcher * qwatcher)
85 : filename_(filename), qwatcher_(qwatcher)
87 QObject::connect(qwatcher, SIGNAL(fileChanged(QString const &)),
88 this, SLOT(notifyChange(QString const &)));
89 if (qwatcher_->files().contains(toqstr(filename)))
90 LYXERR0("This file is already being QFileSystemWatched: " << filename
91 << ". This should not happen.");
96 FileMonitorGuard::~FileMonitorGuard()
98 qwatcher_->removePath(toqstr(filename_));
102 void FileMonitorGuard::refresh(bool new_file)
104 QString const qfilename = toqstr(filename_);
105 if(!qwatcher_->files().contains(qfilename)) {
106 bool exists = QFile(qfilename).exists();
107 if (!exists || !qwatcher_->addPath(qfilename)) {
110 "Could not add path to QFileSystemWatcher: "
112 QTimer::singleShot(1000, this, [=](){
113 refresh(new_file || !exists);
115 } else if (exists && new_file)
116 Q_EMIT fileChanged();
121 void FileMonitorGuard::notifyChange(QString const & path)
123 if (path == toqstr(filename_)) {
124 Q_EMIT fileChanged();
125 // If the file has been modified by delete-move, we are notified of the
126 // deletion but we no longer track the file. See
127 // <https://bugreports.qt.io/browse/QTBUG-46483> (not a bug).
133 FileMonitor2::FileMonitor2(std::shared_ptr<FileMonitorGuard> monitor)
136 connectToFileMonitorGuard();
141 void FileMonitor2::connectToFileMonitorGuard()
143 QObject::connect(monitor_.get(), SIGNAL(fileChanged()),
144 this, SLOT(changed()));
148 boost::signals2::connection
149 FileMonitor2::connect(sig::slot_type const & slot)
151 return fileChanged_.connect(slot);
155 void FileMonitor2::disconnect()
157 fileChanged_.disconnect_all_slots();
158 QObject::disconnect(this, SIGNAL(fileChanged()));
162 void FileMonitor2::changed()
166 Q_EMIT fileChanged();
170 FileMonitorBlocker FileMonitor2::block(int delay)
172 FileMonitorBlocker blocker = blocker_.lock();
174 blocker_ = blocker = make_shared<FileMonitorBlockerGuard>(this);
175 blocker->setDelay(delay);
180 FileMonitorBlockerGuard::FileMonitorBlockerGuard(FileMonitor2 * parent)
181 : QObject(parent), parent_(parent), delay_(0)
183 QObject::disconnect(parent_->monitor_.get(), SIGNAL(fileChanged()),
184 parent_, SLOT(changed()));
188 void FileMonitorBlockerGuard::setDelay(int delay)
190 delay_ = max(delay_, delay);
194 FileMonitorBlockerGuard::~FileMonitorBlockerGuard()
196 // closures can only copy local copies
197 FileMonitor2 * parent = parent_;
198 // parent is also our QObject::parent() so we are deleted before parent.
199 // Even if delay_ is 0, the QTimer is necessary. Indeed, the notifications
200 // from QFileSystemWatcher that we meant to ignore are not going to be
201 // treated immediately, so we must yield to give us the opportunity to
203 QTimer::singleShot(delay_, parent, [parent]() {
204 parent->connectToFileMonitorGuard();
208 } // namespace support
211 #include "moc_FileMonitor2.cpp"