Added a base::Callback interface to FilePathWatcher.
BUG=130980
TEST=browser_tests:FilePathWatcher* are green
Review URL: https://chromiumcodereview.appspot.com/10519003
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@140285 0039d316-1c4b-4281-b951-d872f2087c98
CrOS-Libchrome-Original-Commit: 10e38b62dec4cd25b15439ea33df703d1285fc88
diff --git a/base/files/file_path_watcher.cc b/base/files/file_path_watcher.cc
index 086da1e..dd2b37f 100644
--- a/base/files/file_path_watcher.cc
+++ b/base/files/file_path_watcher.cc
@@ -13,6 +13,33 @@
namespace base {
namespace files {
+namespace {
+
+// A delegate implementation for the callback interface.
+class FilePathWatcherDelegate : public base::files::FilePathWatcher::Delegate {
+ public:
+ explicit FilePathWatcherDelegate(const FilePathWatcher::Callback& callback)
+ : callback_(callback) {}
+
+ // FilePathWatcher::Delegate implementation.
+ virtual void OnFilePathChanged(const FilePath& path) OVERRIDE {
+ callback_.Run(path, false);
+ }
+
+ virtual void OnFilePathError(const FilePath& path) OVERRIDE {
+ callback_.Run(path, true);
+ }
+
+ private:
+ virtual ~FilePathWatcherDelegate() {}
+
+ FilePathWatcher::Callback callback_;
+
+ DISALLOW_COPY_AND_ASSIGN(FilePathWatcherDelegate);
+};
+
+} // namespace
+
FilePathWatcher::~FilePathWatcher() {
impl_->Cancel();
}
@@ -35,5 +62,9 @@
DCHECK(is_cancelled());
}
+bool FilePathWatcher::Watch(const FilePath& path, const Callback& callback) {
+ return Watch(path, new FilePathWatcherDelegate(callback));
+}
+
} // namespace files
} // namespace base
diff --git a/base/files/file_path_watcher.h b/base/files/file_path_watcher.h
index 3795c9e..5919994 100644
--- a/base/files/file_path_watcher.h
+++ b/base/files/file_path_watcher.h
@@ -10,6 +10,7 @@
#include "base/base_export.h"
#include "base/basictypes.h"
+#include "base/callback.h"
#include "base/file_path.h"
#include "base/memory/ref_counted.h"
#include "base/message_loop_proxy.h"
@@ -28,9 +29,16 @@
// details.
class BASE_EXPORT FilePathWatcher {
public:
+ // Callback type for Watch(). |path| points to the file that was updated,
+ // and |error| is true if the platform specific code detected an error. In
+ // that case, the callback won't be invoked again.
+ typedef base::Callback<void(const FilePath& path, bool error)> Callback;
+
// Declares the callback client code implements to receive notifications. Note
// that implementations of this interface should not keep a reference to the
// corresponding FileWatcher object to prevent a reference cycle.
+ //
+ // Deprecated: see comment on Watch() below.
class Delegate : public base::RefCountedThreadSafe<Delegate> {
public:
virtual void OnFilePathChanged(const FilePath& path) = 0;
@@ -104,9 +112,18 @@
// back for each change. Returns true on success.
// OnFilePathChanged() will be called on the same thread as Watch() is called,
// which should have a MessageLoop of TYPE_IO.
+ //
+ // Deprecated: new code should use the callback interface, declared below.
+ // The FilePathWatcher::Delegate interface will be removed once all client
+ // code has been updated. http://crbug.com/130980
virtual bool Watch(const FilePath& path, Delegate* delegate)
WARN_UNUSED_RESULT;
+ // Invokes |callback| whenever updates to |path| are detected. This should be
+ // called at most once, and from a MessageLoop of TYPE_IO. The callback will
+ // be invoked on the same loop. Returns true on success.
+ bool Watch(const FilePath& path, const Callback& callback);
+
private:
scoped_refptr<PlatformDelegate> impl_;
diff --git a/base/files/file_path_watcher_browsertest.cc b/base/files/file_path_watcher_browsertest.cc
index 7886df8..5eea88c 100644
--- a/base/files/file_path_watcher_browsertest.cc
+++ b/base/files/file_path_watcher_browsertest.cc
@@ -119,7 +119,7 @@
DISALLOW_COPY_AND_ASSIGN(TestDelegate);
};
-void SetupWatchCallback(const FilePath& target,
+void SetupWatchDelegate(const FilePath& target,
FilePathWatcher* watcher,
FilePathWatcher::Delegate* delegate,
bool* result,
@@ -128,6 +128,25 @@
completion->Signal();
}
+void SetupWatchCallback(const FilePath& target,
+ FilePathWatcher* watcher,
+ const FilePathWatcher::Callback& callback) {
+ ASSERT_TRUE(watcher->Watch(target, callback));
+}
+
+void QuitLoopWatchCallback(MessageLoop* loop,
+ const FilePath& expected_path,
+ bool expected_error,
+ bool* flag,
+ const FilePath& path,
+ bool error) {
+ ASSERT_TRUE(flag);
+ *flag = true;
+ EXPECT_EQ(expected_path, path);
+ EXPECT_EQ(expected_error, error);
+ loop->PostTask(FROM_HERE, loop->QuitClosure());
+}
+
class FilePathWatcherTest : public testing::Test {
public:
FilePathWatcherTest()
@@ -170,7 +189,7 @@
bool result;
file_thread_.message_loop_proxy()->PostTask(
FROM_HERE,
- base::Bind(SetupWatchCallback, target, watcher,
+ base::Bind(SetupWatchDelegate, target, watcher,
make_scoped_refptr(delegate), &result, &completion));
completion.Wait();
return result;
@@ -239,6 +258,32 @@
ASSERT_TRUE(WaitForEvents());
}
+TEST_F(FilePathWatcherTest, Callback) {
+ FilePathWatcher watcher;
+ bool called_back = false;
+
+ MessageLoop* file_loop = file_thread_.message_loop();
+ ASSERT_TRUE(file_loop);
+ // The callback makes |loop_| quit on file events, and flips |called_back|
+ // to true.
+ FilePathWatcher::Callback callback = base::Bind(
+ QuitLoopWatchCallback, &loop_, test_file(), false, &called_back);
+
+ // Start watching on the file thread, and unblock the loop once the callback
+ // has been installed.
+ file_thread_.message_loop_proxy()->PostTaskAndReply(
+ FROM_HERE,
+ base::Bind(SetupWatchCallback, test_file(), &watcher, callback),
+ base::Bind(&MessageLoop::Quit, base::Unretained(&loop_)));
+ loop_.Run();
+
+ // The watch has been installed. Trigger a file event now, which will unblock
+ // the loop again.
+ ASSERT_TRUE(WriteFile(test_file(), "content"));
+ loop_.Run();
+ EXPECT_TRUE(called_back);
+}
+
// Used by the DeleteDuringNotify test below.
// Deletes the FilePathWatcher when it's notified.
class Deleter : public FilePathWatcher::Delegate {