2 * Copyright (c) 2011 Sveriges Television AB <info@casparcg.com>
4 * This file is part of CasparCG (www.casparcg.com).
6 * CasparCG is free software: you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation, either version 3 of the License, or
9 * (at your option) any later version.
11 * CasparCG is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with CasparCG. If not, see <http://www.gnu.org/licenses/>.
19 * Author: Helge Norberg, helge.norberg@svt.se
24 #include "polling_filesystem_monitor.h"
31 #include <boost/thread.hpp>
32 #include <boost/foreach.hpp>
33 #include <boost/range/adaptor/map.hpp>
34 #include <boost/range/algorithm/copy.hpp>
35 #include <boost/filesystem/fstream.hpp>
36 #include <boost/filesystem/convenience.hpp>
38 #include <tbb/atomic.h>
39 #include <tbb/concurrent_queue.h>
45 class exception_protected_handler
47 filesystem_monitor_handler handler_;
49 exception_protected_handler(const filesystem_monitor_handler& handler)
54 void operator()(filesystem_event event, const boost::filesystem::wpath& file)
58 boost::this_thread::interruption_point();
59 handler_(event, file);
60 boost::this_thread::interruption_point();
62 catch (const boost::thread_interrupted&)
68 CASPAR_LOG_CURRENT_EXCEPTION();
73 class directory_monitor
75 bool report_already_existing_;
76 boost::filesystem::wpath folder_;
77 filesystem_event events_mask_;
78 filesystem_monitor_handler handler_;
79 initial_files_handler initial_files_handler_;
81 std::map<boost::filesystem::wpath, std::time_t> files_;
82 std::map<boost::filesystem::wpath, uintmax_t> being_written_sizes_;
85 bool report_already_existing,
86 const boost::filesystem::wpath& folder,
87 filesystem_event events_mask,
88 const filesystem_monitor_handler& handler,
89 const initial_files_handler& initial_files_handler)
90 : report_already_existing_(report_already_existing)
92 , events_mask_(events_mask)
93 , handler_(exception_protected_handler(handler))
94 , initial_files_handler_(initial_files_handler)
101 if ((events_mask_ & MODIFIED) == 0)
104 BOOST_FOREACH(auto& file, files_)
105 handler_(MODIFIED, file.first);
108 void reemmit(const boost::filesystem::wpath& file)
110 if ((events_mask_ & MODIFIED) == 0)
113 if (files_.find(file) != files_.end() && boost::filesystem::exists(file))
114 handler_(MODIFIED, file);
117 void scan(const boost::function<bool ()>& should_abort)
119 static const std::time_t NO_LONGER_WRITING_AGE = 3; // Assume std::time_t is expressed in seconds
120 using namespace boost::filesystem;
122 bool interested_in_removed = (events_mask_ & REMOVED) > 0;
123 bool interested_in_created = (events_mask_ & CREATED) > 0;
124 bool interested_in_modified = (events_mask_ & MODIFIED) > 0;
126 std::set<wpath> removed_files;
128 files_ | boost::adaptors::map_keys,
129 std::insert_iterator<decltype(removed_files)>(removed_files, removed_files.end()));
131 std::set<wpath> initial_files;
133 for (boost::filesystem3::wrecursive_directory_iterator iter(folder_); iter != boost::filesystem3::wrecursive_directory_iterator(); ++iter)
138 auto& path = iter->path();
140 if (is_directory(path))
143 auto now = std::time(nullptr);
144 std::time_t current_mtime;
148 current_mtime = last_write_time(path);
152 // Probably removed, will be captured the next round.
156 auto time_since_written_to = now - current_mtime;
157 bool no_longer_being_written_to = time_since_written_to >= NO_LONGER_WRITING_AGE;
158 auto previous_it = files_.find(path);
159 bool already_known = previous_it != files_.end();
161 if (already_known && no_longer_being_written_to)
163 bool modified = previous_it->second != current_mtime;
165 if (modified && can_read_file(path))
167 if (interested_in_modified)
168 handler_(MODIFIED, path);
170 files_[path] = current_mtime;
171 being_written_sizes_.erase(path);
174 else if (no_longer_being_written_to && can_read_file(path))
176 if (interested_in_created && (report_already_existing_ || !first_scan_))
177 handler_(CREATED, path);
180 initial_files.insert(path);
182 files_.insert(std::make_pair(path, current_mtime));
183 being_written_sizes_.erase(path);
186 removed_files.erase(path);
189 BOOST_FOREACH(auto& path, removed_files)
192 being_written_sizes_.erase(path);
194 if (interested_in_removed)
195 handler_(REMOVED, path);
199 initial_files_handler_(initial_files);
204 bool can_read_file(const boost::filesystem::wpath& file)
206 boost::filesystem::wifstream stream(file);
208 return stream.is_open();
212 class polling_filesystem_monitor : public filesystem_monitor
214 directory_monitor root_monitor_;
215 boost::thread scanning_thread_;
216 tbb::atomic<bool> running_;
217 int scan_interval_millis_;
218 boost::promise<void> initial_scan_completion_;
219 tbb::concurrent_queue<boost::filesystem::wpath> to_reemmit_;
220 tbb::atomic<bool> reemmit_all_;
222 polling_filesystem_monitor(
223 const boost::filesystem::wpath& folder_to_watch,
224 filesystem_event events_of_interest_mask,
225 bool report_already_existing,
226 int scan_interval_millis,
227 const filesystem_monitor_handler& handler,
228 const initial_files_handler& initial_files_handler)
229 : root_monitor_(report_already_existing, folder_to_watch, events_of_interest_mask, handler, initial_files_handler)
230 , scan_interval_millis_(scan_interval_millis)
233 reemmit_all_ = false;
234 scanning_thread_ = boost::thread([this] { scanner(); });
237 virtual ~polling_filesystem_monitor()
240 scanning_thread_.interrupt();
241 scanning_thread_.join();
244 virtual boost::unique_future<void> initial_files_processed()
246 return initial_scan_completion_.get_future();
249 virtual void reemmit_all()
254 virtual void reemmit(const boost::filesystem::wpath& file)
256 to_reemmit_.push(file);
261 win32_exception::install_handler();
263 //detail::SetThreadName(GetCurrentThreadId(), "polling_filesystem_monitor");
265 bool running = scan(false);
266 initial_scan_completion_.set_value();
272 bool scan(bool sleep)
277 boost::this_thread::sleep(boost::posix_time::milliseconds(scan_interval_millis_));
279 if (reemmit_all_.fetch_and_store(false))
280 root_monitor_.reemmit_all();
283 boost::filesystem::wpath file;
285 while (to_reemmit_.try_pop(file))
286 root_monitor_.reemmit(file);
289 root_monitor_.scan([=] { return !running_; });
291 catch (const boost::thread_interrupted&)
296 CASPAR_LOG_CURRENT_EXCEPTION();
303 struct polling_filesystem_monitor_factory::impl
305 int scan_interval_millis;
307 impl(int scan_interval_millis)
308 : scan_interval_millis(scan_interval_millis)
313 polling_filesystem_monitor_factory::polling_filesystem_monitor_factory(int scan_interval_millis)
314 : impl_(new impl(scan_interval_millis))
318 polling_filesystem_monitor_factory::~polling_filesystem_monitor_factory()
322 filesystem_monitor::ptr polling_filesystem_monitor_factory::create(
323 const boost::filesystem::wpath& folder_to_watch,
324 filesystem_event events_of_interest_mask,
325 bool report_already_existing,
326 const filesystem_monitor_handler& handler,
327 const initial_files_handler& initial_files_handler)
329 return spl::make_shared<polling_filesystem_monitor>(
331 events_of_interest_mask,
332 report_already_existing,
333 impl_->scan_interval_millis,
335 initial_files_handler);