1 files changed, 127 insertions, 88 deletions

diff --git a/webkit/blob/local_file_reader.cc b/webkit/blob/local_file_reader.cc
index 8b5fb05..068ad13 100644
--- a/webkit/blob/local_file_reader.cc
+++ b/webkit/blob/local_file_reader.cc
@@ -30,6 +30,39 @@ bool VerifySnapshotTime(const base::Time& expected_modification_time,
              file_info.last_modified.ToTimeT();
 }
 
+void DidGetFileInfoForGetLength(const net::Int64CompletionCallback& callback,
+                                const base::Time& expected_modification_time,
+                                base::PlatformFileError error,
+                                const base::PlatformFileInfo& file_info) {
+  if (file_info.is_directory) {
+    callback.Run(net::ERR_FILE_NOT_FOUND);
+    return;
+  }
+  if (error != base::PLATFORM_FILE_OK) {
+    callback.Run(LocalFileReader::PlatformFileErrorToNetError(error));
+    return;
+  }
+  if (!VerifySnapshotTime(expected_modification_time, file_info)) {
+    callback.Run(net::ERR_UPLOAD_FILE_CHANGED);
+    return;
+  }
+  callback.Run(file_info.size);
+}
+
+void DidSeekFile(const LocalFileReader::OpenFileStreamCallback& callback,
+                 scoped_ptr<net::FileStream> stream_impl,
+                 int64 initial_offset,
+                 int64 new_offset) {
+  int result = net::OK;
+  if (new_offset < 0)
+    result = static_cast<int>(new_offset);
+  else if (new_offset != initial_offset)
+    result = net::ERR_REQUEST_RANGE_NOT_SATISFIABLE;
+  callback.Run(result, stream_impl.Pass());
+}
+
+void EmptyCompletionCallback(int) {}
+
 }  // namespace
 
 // static
@@ -47,6 +80,70 @@ int LocalFileReader::PlatformFileErrorToNetError(
   }
 }
 
+// A helper class to open, verify and seek a file stream for a given path.
+class LocalFileReader::OpenFileStreamHelper {
+ public:
+  explicit OpenFileStreamHelper(base::MessageLoopProxy* file_thread_proxy)
+      : file_thread_proxy_(file_thread_proxy),
+        file_handle_(base::kInvalidPlatformFileValue),
+        result_(net::OK) {}
+  ~OpenFileStreamHelper() {
+    if (file_handle_ != base::kInvalidPlatformFileValue) {
+      file_thread_proxy_->PostTask(
+          FROM_HERE,
+          base::Bind(base::IgnoreResult(&base::ClosePlatformFile),
+                     file_handle_));
+    }
+  }
+
+  void OpenAndVerifyOnFileThread(const FilePath& file_path,
+                                 const base::Time& expected_modification_time) {
+    base::PlatformFileError file_error = base::PLATFORM_FILE_OK;
+    file_handle_ = base::CreatePlatformFile(
+        file_path, kOpenFlagsForRead, NULL, &file_error);
+    if (file_error != base::PLATFORM_FILE_OK) {
+      result_ = PlatformFileErrorToNetError(file_error);
+      return;
+    }
+    DCHECK_NE(base::kInvalidPlatformFileValue, file_handle_);
+    base::PlatformFileInfo file_info;
+    if (!base::GetPlatformFileInfo(file_handle_, &file_info)) {
+      result_ = net::ERR_FAILED;
+      return;
+    }
+    if (!VerifySnapshotTime(expected_modification_time, file_info)) {
+      result_ = net::ERR_UPLOAD_FILE_CHANGED;
+      return;
+    }
+    result_ = net::OK;
+  }
+
+  void OpenStreamOnCallingThread(int64 initial_offset,
+                                 const OpenFileStreamCallback& callback) {
+    DCHECK(!callback.is_null());
+    scoped_ptr<net::FileStream> stream_impl;
+    if (result_ != net::OK) {
+      callback.Run(result_, stream_impl.Pass());
+      return;
+    }
+    stream_impl.reset(
+        new net::FileStream(file_handle_, kOpenFlagsForRead, NULL));
+    file_handle_ = base::kInvalidPlatformFileValue;
+    result_ = stream_impl->Seek(net::FROM_BEGIN, initial_offset,
+                                base::Bind(&DidSeekFile, callback,
+                                           base::Passed(&stream_impl),
+                                           initial_offset));
+    if (result_ != net::ERR_IO_PENDING)
+      callback.Run(result_, stream_impl.Pass());
+  }
+
+ private:
+  scoped_refptr<base::MessageLoopProxy> file_thread_proxy_;
+  base::PlatformFile file_handle_;
+  int result_;
+  DISALLOW_COPY_AND_ASSIGN(OpenFileStreamHelper);
+};
+
 LocalFileReader::LocalFileReader(
     base::MessageLoopProxy* file_thread_proxy,
     const FilePath& file_path,
@@ -60,6 +157,9 @@ LocalFileReader::LocalFileReader(
       weak_factory_(ALLOW_THIS_IN_INITIALIZER_LIST(this)) {}
 
 LocalFileReader::~LocalFileReader() {
+  if (!stream_impl_.get())
+    return;
+  stream_impl_->Close(base::Bind(&EmptyCompletionCallback));
 }
 
 int LocalFileReader::Read(net::IOBuffer* buf, int buf_len,
@@ -67,113 +167,52 @@ int LocalFileReader::Read(net::IOBuffer* buf, int buf_len,
   DCHECK(!has_pending_open_);
   if (stream_impl_.get())
     return stream_impl_->Read(buf, buf_len, callback);
-  return Open(base::Bind(&LocalFileReader::DidOpenForRead,
-                         weak_factory_.GetWeakPtr(),
+  return Open(base::Bind(&LocalFileReader::DidOpen, weak_factory_.GetWeakPtr(),
                          make_scoped_refptr(buf), buf_len, callback));
 }
 
 int LocalFileReader::GetLength(const net::Int64CompletionCallback& callback) {
   const bool posted = base::FileUtilProxy::GetFileInfo(
       file_thread_proxy_, file_path_,
-      base::Bind(&LocalFileReader::DidGetFileInfoForGetLength,
-                 weak_factory_.GetWeakPtr(), callback));
+      base::Bind(&DidGetFileInfoForGetLength, callback,
+                 expected_modification_time_));
   DCHECK(posted);
   return net::ERR_IO_PENDING;
 }
 
-int LocalFileReader::Open(const net::CompletionCallback& callback) {
+int LocalFileReader::Open(const OpenFileStreamCallback& callback) {
   DCHECK(!has_pending_open_);
   DCHECK(!stream_impl_.get());
   has_pending_open_ = true;
-
-  // Call GetLength first to make it perform last-modified-time verification,
-  // and then call DidVerifyForOpen for do the rest.
-  return GetLength(base::Bind(&LocalFileReader::DidVerifyForOpen,
-                              weak_factory_.GetWeakPtr(), callback));
-}
-
-void LocalFileReader::DidVerifyForOpen(
-    const net::CompletionCallback& callback,
-    int64 get_length_result) {
-  if (get_length_result < 0) {
-    callback.Run(static_cast<int>(get_length_result));
-    return;
-  }
-
-  stream_impl_.reset(new net::FileStream(NULL));
-  const int result = stream_impl_->Open(
-      file_path_, kOpenFlagsForRead,
-      base::Bind(&LocalFileReader::DidOpenFileStream,
-                 weak_factory_.GetWeakPtr(),
-                 callback));
-  if (result != net::ERR_IO_PENDING)
-    callback.Run(result);
-}
-
-void LocalFileReader::DidOpenFileStream(
-    const net::CompletionCallback& callback,
-    int result) {
-  if (result != net::OK) {
-    callback.Run(result);
-    return;
-  }
-  result = stream_impl_->Seek(net::FROM_BEGIN, initial_offset_,
-                              base::Bind(&LocalFileReader::DidSeekFileStream,
-                                         weak_factory_.GetWeakPtr(),
-                                         callback));
-  if (result != net::ERR_IO_PENDING) {
-    callback.Run(result);
-  }
-}
-
-void LocalFileReader::DidSeekFileStream(
-    const net::CompletionCallback& callback,
-    int64 seek_result) {
-  if (seek_result < 0) {
-    callback.Run(static_cast<int>(seek_result));
-    return;
-  }
-  if (seek_result != initial_offset_) {
-    callback.Run(net::ERR_REQUEST_RANGE_NOT_SATISFIABLE);
-    return;
-  }
-  callback.Run(net::OK);
+  OpenFileStreamHelper* helper = new OpenFileStreamHelper(file_thread_proxy_);
+  const bool posted = file_thread_proxy_->PostTaskAndReply(
+      FROM_HERE,
+      base::Bind(&OpenFileStreamHelper::OpenAndVerifyOnFileThread,
+                 base::Unretained(helper), file_path_,
+                 expected_modification_time_),
+      base::Bind(&OpenFileStreamHelper::OpenStreamOnCallingThread,
+                 base::Owned(helper), initial_offset_, callback));
+  DCHECK(posted);
+  return net::ERR_IO_PENDING;
 }
 
-void LocalFileReader::DidOpenForRead(net::IOBuffer* buf,
-                                     int buf_len,
-                                     const net::CompletionCallback& callback,
-                                     int open_result) {
+void LocalFileReader::DidOpen(net::IOBuffer* buf,
+                              int buf_len,
+                              const net::CompletionCallback& callback,
+                              int open_error,
+                              scoped_ptr<net::FileStream> stream_impl) {
   DCHECK(has_pending_open_);
+  DCHECK(!stream_impl_.get());
   has_pending_open_ = false;
-  if (open_result != net::OK) {
-    stream_impl_.reset();
-    callback.Run(open_result);
+  if (open_error != net::OK) {
+    callback.Run(open_error);
     return;
   }
-  DCHECK(stream_impl_.get());
-  const int read_result = stream_impl_->Read(buf, buf_len, callback);
-  if (read_result != net::ERR_IO_PENDING)
-    callback.Run(read_result);
-}
-
-void LocalFileReader::DidGetFileInfoForGetLength(
-    const net::Int64CompletionCallback& callback,
-    base::PlatformFileError error,
-    const base::PlatformFileInfo& file_info) {
-  if (file_info.is_directory) {
-    callback.Run(net::ERR_FILE_NOT_FOUND);
-    return;
-  }
-  if (error != base::PLATFORM_FILE_OK) {
-    callback.Run(LocalFileReader::PlatformFileErrorToNetError(error));
-    return;
-  }
-  if (!VerifySnapshotTime(expected_modification_time_, file_info)) {
-    callback.Run(net::ERR_UPLOAD_FILE_CHANGED);
-    return;
-  }
-  callback.Run(file_info.size);
+  DCHECK(stream_impl.get());
+  stream_impl_ = stream_impl.Pass();
+  const int read_error = stream_impl_->Read(buf, buf_len, callback);
+  if (read_error != net::ERR_IO_PENDING)
+    callback.Run(read_error);
 }
 
 }  // namespace webkit_blob