1 // Copyright (c) 2009 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #include "base/directory_watcher.h" 6 7 #include <CoreServices/CoreServices.h> 8 9 #include "base/file_path.h" 10 #include "base/file_util.h" 11 #include "base/logging.h" 12 #include "base/message_loop.h" 13 #include "base/scoped_cftyperef.h" 14 15 namespace { 16 17 const CFAbsoluteTime kEventLatencySeconds = 0.3; 18 19 class DirectoryWatcherImpl : public DirectoryWatcher::PlatformDelegate { 20 public: 21 DirectoryWatcherImpl() {} 22 ~DirectoryWatcherImpl() { 23 if (!path_.value().empty()) { 24 FSEventStreamStop(fsevent_stream_); 25 FSEventStreamInvalidate(fsevent_stream_); 26 FSEventStreamRelease(fsevent_stream_); 27 } 28 } 29 30 virtual bool Watch(const FilePath& path, DirectoryWatcher::Delegate* delegate, 31 MessageLoop* backend_loop, bool recursive); 32 33 void OnFSEventsCallback(const FilePath& event_path) { 34 DCHECK(!path_.value().empty()); 35 if (!recursive_) { 36 FilePath absolute_event_path = event_path; 37 if (!file_util::AbsolutePath(&absolute_event_path)) 38 return; 39 if (absolute_event_path != path_) 40 return; 41 } 42 delegate_->OnDirectoryChanged(path_); 43 } 44 45 private: 46 // Delegate to notify upon changes. 47 DirectoryWatcher::Delegate* delegate_; 48 49 // Path we're watching (passed to delegate). 50 FilePath path_; 51 52 // Indicates recursive watch. 53 bool recursive_; 54 55 // Backend stream we receive event callbacks from (strong reference). 56 FSEventStreamRef fsevent_stream_; 57 58 DISALLOW_COPY_AND_ASSIGN(DirectoryWatcherImpl); 59 }; 60 61 void FSEventsCallback(ConstFSEventStreamRef stream, 62 void* event_watcher, size_t num_events, 63 void* event_paths, const FSEventStreamEventFlags flags[], 64 const FSEventStreamEventId event_ids[]) { 65 char** paths = reinterpret_cast<char**>(event_paths); 66 DirectoryWatcherImpl* watcher = 67 reinterpret_cast<DirectoryWatcherImpl*> (event_watcher); 68 for (size_t i = 0; i < num_events; i++) { 69 watcher->OnFSEventsCallback(FilePath(paths[i])); 70 } 71 } 72 73 bool DirectoryWatcherImpl::Watch(const FilePath& path, 74 DirectoryWatcher::Delegate* delegate, 75 MessageLoop* backend_loop, 76 bool recursive) { 77 DCHECK(path_.value().empty()); // Can only watch one path. 78 79 DCHECK(MessageLoop::current()->type() == MessageLoop::TYPE_UI); 80 81 if (!file_util::PathExists(path)) 82 return false; 83 84 path_ = path; 85 if (!file_util::AbsolutePath(&path_)) { 86 path_ = FilePath(); // Make sure we're marked as not-in-use. 87 return false; 88 } 89 delegate_ = delegate; 90 recursive_ = recursive; 91 92 scoped_cftyperef<CFStringRef> cf_path(CFStringCreateWithCString( 93 NULL, path.value().c_str(), kCFStringEncodingMacHFS)); 94 CFStringRef path_for_array = cf_path.get(); 95 scoped_cftyperef<CFArrayRef> watched_paths(CFArrayCreate( 96 NULL, reinterpret_cast<const void**>(&path_for_array), 1, 97 &kCFTypeArrayCallBacks)); 98 99 FSEventStreamContext context; 100 context.version = 0; 101 context.info = this; 102 context.retain = NULL; 103 context.release = NULL; 104 context.copyDescription = NULL; 105 106 fsevent_stream_ = FSEventStreamCreate(NULL, &FSEventsCallback, &context, 107 watched_paths, 108 kFSEventStreamEventIdSinceNow, 109 kEventLatencySeconds, 110 kFSEventStreamCreateFlagNone); 111 FSEventStreamScheduleWithRunLoop(fsevent_stream_, CFRunLoopGetCurrent(), 112 kCFRunLoopDefaultMode); 113 FSEventStreamStart(fsevent_stream_); 114 115 return true; 116 } 117 118 } // namespace 119 120 DirectoryWatcher::DirectoryWatcher() { 121 impl_ = new DirectoryWatcherImpl(); 122 } 123