Add function to document_loader to get PDF as pp::FileRef

pdf/file_writer.cc

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "pdf/file_writer.h"
+
+#include "ppapi/c/ppb_file_io.h"
+
+namespace chrome_pdf {
+
+FileWriter::FileWriter(
+    const pp::InstanceHandle& instance,
+    const std::string& filename,
+    const char* bytes,
+    size_t length)
+    : instance_(instance),
+      filename_(filename),
+      bytes_(bytes),
+      length_(length),
+      succeeded_(false),
+      offset_(0),
+      fs_(instance, PP_FILESYSTEMTYPE_ISOLATED),
+      io_(instance),
+      callback_factory_(this) {
+}
+
+void FileWriter::GetFile(
+    pp::CompletionCallbackWithOutput<pp::FileRef> callback) {
+  if (callback_) {
+    callback.Run(PP_ERROR_INPROGRESS);
+    return;
+  }
+  if (succeeded_) {
+    *(callback.output()) = file_ref_.pp_resource();
+    callback.Run(PP_OK);
+    return;
+  }
+
+  callback_.reset(new pp::CompletionCallbackWithOutput<pp::FileRef>(callback));
+  fs_.Open(length_,
+           callback_factory_.NewCallback(&FileWriter::OnFileSystemOpen));
+}
+
+void FileWriter::OnFileSystemOpen(int32_t result) {
+  if (result != PP_OK) {
+    callback_->Run(result);
+    callback_.reset();
+    return;
+  }
+  file_ref_ = pp::FileRef(fs_, filename_.c_str());
+  io_.Open(file_ref_,
+           PP_FILEOPENFLAG_CREATE | PP_FILEOPENFLAG_WRITE,
+           callback_factory_.NewCallback(&FileWriter::OnWriteComplete));
+}
+
+void FileWriter::OnWriteComplete(int32_t result) {
+  if (result != PP_OK) {
+    io_.close();
+    callback_->Run(result);
+    callback_.reset();
+    return;
+  }
+  if (offset_ == length_) {
+    io_.Flush(callback_factory_.NewCallback(&FileWriter::OnFlushComplete));
+    return;
+  }
+  offset_ += io_.Write(
+      offset_,
+      bytes_,
+      length_ - offset_,
+      callback_factory_.NewCallback(&FileWriter::OnWriteComplete));
+}
+
+void FileWriter::OnFlushComplete(int32_t result) {
+  if (result != PP_OK) {
+    io_.close();
+    callback_->Run(result);
+    callback_.reset();
+    return;
+  }
+
+  succeeded_ = true;
+  io_.Close();
+  *(callback_->output()) = file_ref_.pp_resource();
+  callback_->Run(result);
+  callback_.reset();
+}
+
+}  // namespace chrome_pdf