Refactor FileIO to the new design

ppapi/proxy/file_io_resource.cc

+// Copyright (c) 2012 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 "ppapi/proxy/file_io_resource.h"
+
+#include "base/bind.h"
+#include "ipc/ipc_message.h"
+#include "ppapi/c/pp_errors.h"
+#include "ppapi/proxy/ppapi_messages.h"
+#include "ppapi/shared_impl/array_writer.h"
+#include "ppapi/shared_impl/ppapi_globals.h"
+#include "ppapi/shared_impl/resource_tracker.h"
+#include "ppapi/thunk/ppb_file_ref_api.h"
+
+using ppapi::thunk::PPB_FileRef_API;
+
+namespace {
+
+// An adapter to let Read() share the same implementation with ReadToArray().
+void* DummyGetDataBuffer(void* user_data, uint32_t count, uint32_t size) {
+  return user_data;
+}
+
+}  // namespace
+
+namespace ppapi {
+namespace proxy {
+
+FileIOResource::FileIOResource(Connection connection, PP_Instance instance)
+    : PluginResource(connection, instance),
+      PPB_FileIO_Shared(),
+      num_pending_ops_(0),
+      pending_op_(OPERATION_NONE) {
+  SendCreate(RENDERER, PpapiHostMsg_FileIO_Create());
+}
+
+FileIOResource::~FileIOResource() {
+}
+
+thunk::PPB_FileIO_API* FileIOResource::AsPPB_FileIO_API() {
+  return this;
+}
+
+int32_t FileIOResource::Open(PP_Resource file_ref,
+                             int32_t open_flags,
+                             scoped_refptr<TrackedCallback> callback) {
+  temp_callback_ = callback;
+  return PPB_FileIO_Shared::DoOpen(file_ref, open_flags);
+}
+
+int32_t FileIOResource::Query(PP_FileInfo* info,
+                              scoped_refptr<TrackedCallback> callback) {
+  temp_callback_ = callback;
+  temp_info_ = info;
+  return DoQuery();
+}
+
+int32_t FileIOResource::Touch(PP_Time last_access_time,
+                              PP_Time last_modified_time,
+                              scoped_refptr<TrackedCallback> callback) {
+  temp_callback_ = callback;
+  return DoTouch(last_access_time, last_modified_time);
+}
+
+int32_t FileIOResource::Read(int64_t offset,
+                             char* buffer,
+                             int32_t bytes_to_read,
+                             scoped_refptr<TrackedCallback> callback) {
+  temp_callback_ = callback;
+  temp_array_output_.GetDataBuffer = &DummyGetDataBuffer;
+  temp_array_output_.user_data = buffer;
+  return PPB_FileIO_Shared::DoRead(offset, bytes_to_read);
+}
+
+int32_t FileIOResource::ReadToArray(int64_t offset,
+                                    int32_t max_read_length,
+                                    PP_ArrayOutput* array_output,
+                                    scoped_refptr<TrackedCallback> callback) {
+  DCHECK(array_output);
+  temp_callback_ = callback;
+  temp_array_output_ = *array_output;
+  return PPB_FileIO_Shared::DoRead(offset, max_read_length);
+}
+
+int32_t FileIOResource::Write(int64_t offset,
+                              const char* buffer,
+                              int32_t bytes_to_write,
+                              scoped_refptr<TrackedCallback> callback) {
+  temp_callback_ = callback;
+  return PPB_FileIO_Shared::DoWrite(offset, buffer, bytes_to_write);
+}
+
+int32_t FileIOResource::SetLength(int64_t length,
+                                  scoped_refptr<TrackedCallback> callback) {
+  temp_callback_ = callback;
+  return PPB_FileIO_Shared::DoSetLength(length);
+}
+
+int32_t FileIOResource::Flush(scoped_refptr<TrackedCallback> callback) {
+  temp_callback_ = callback;
+  return PPB_FileIO_Shared::DoFlush();
+}
+
+void FileIOResource::Close() {
+  Post(RENDERER, PpapiHostMsg_FileIO_Close());
+}
+
+int32_t FileIOResource::GetOSFileDescriptor() {
+  return -1;  // FIXME: deprecated
+}
+
+int32_t FileIOResource::WillWrite(int64_t offset,
+                                  int32_t bytes_to_write,
+                                  scoped_refptr<TrackedCallback> callback) {
+  Call<PpapiPluginMsg_FileIO_GeneralComplete>(RENDERER,
+      PpapiHostMsg_FileIO_WillWrite(offset, bytes_to_write),
+      base::Bind(&FileIOResource::OnPluginMsgGeneralComplete, this,
+                 callback));
+  SetOpInProgress(OPERATION_EXCLUSIVE);
+  return PP_OK_COMPLETIONPENDING;
+}
+
+int32_t FileIOResource::WillSetLength(int64_t length,
+                                      scoped_refptr<TrackedCallback> callback) {
+  Call<PpapiPluginMsg_FileIO_GeneralComplete>(RENDERER,
+      PpapiHostMsg_FileIO_WillSetLength(length),
+      base::Bind(&FileIOResource::OnPluginMsgGeneralComplete, this,
+                 callback));
+  SetOpInProgress(OPERATION_EXCLUSIVE);
+  return PP_OK_COMPLETIONPENDING;
+}
+
+int32_t FileIOResource::CommonPreCondition(bool should_be_open,
+                                           OperationType new_op) {
+  if (!CheckOpenState(should_be_open))
+    return PP_ERROR_FAILED;
+
+  if (pending_op_ != OPERATION_NONE &&
+      (pending_op_ != new_op || pending_op_ == OPERATION_EXCLUSIVE))
+    return PP_ERROR_INPROGRESS;
+
+  return PP_OK;
+}
+
+void FileIOResource::CommonPostCondition(OperationType new_op) {
+  SetOpInProgress(new_op);
+}
+
+int32_t FileIOResource::OpenValidated(PP_Resource file_ref_resource,
+                                      PPB_FileRef_API* file_ref_api,
+                                      int32_t open_flags) {
+  Resource* file_ref_object =
+      PpapiGlobals::Get()->GetResourceTracker()->GetResource(file_ref_resource);
+
+  Call<PpapiPluginMsg_FileIO_OpenFileComplete>(RENDERER,
+      PpapiHostMsg_FileIO_Open(
+          file_ref_object->host_resource().host_resource(),
+          open_flags),
+      base::Bind(&FileIOResource::OnPluginMsgOpenFileComplete, this,
+                 temp_callback_));
+  return PP_OK_COMPLETIONPENDING;
+}
+
+int32_t FileIOResource::QueryValidated() {
+  Call<PpapiPluginMsg_FileIO_QueryComplete>(RENDERER,
+      PpapiHostMsg_FileIO_Query(),
+      base::Bind(&FileIOResource::OnPluginMsgQueryComplete, this,
+                 temp_callback_, temp_info_));
+  return PP_OK_COMPLETIONPENDING;
+}
+
+int32_t FileIOResource::TouchValidated(PP_Time last_access_time,
+                                       PP_Time last_modified_time) {
+  Call<PpapiPluginMsg_FileIO_GeneralComplete>(RENDERER,
+      PpapiHostMsg_FileIO_Touch(last_access_time, last_modified_time),
+      base::Bind(&FileIOResource::OnPluginMsgGeneralComplete, this,
+                 temp_callback_));
+  return PP_OK_COMPLETIONPENDING;
+}
+
+int32_t FileIOResource::ReadValidated(int64_t offset,
+                                      int32_t bytes_to_read) {
+  Call<PpapiPluginMsg_FileIO_ReadComplete>(RENDERER,
+      PpapiHostMsg_FileIO_Read(offset, bytes_to_read),
+      base::Bind(&FileIOResource::OnPluginMsgReadComplete, this,
+                 temp_callback_, temp_array_output_));
+  return PP_OK_COMPLETIONPENDING;
+}
+
+int32_t FileIOResource::WriteValidated(int64_t offset,
+                                       const char* buffer,
+                                       int32_t bytes_to_write) {
+  // TODO(brettw) it would be nice to use a shared memory buffer for large
+  // writes rather than having to copy to a string (which will involve a number
+  // of extra copies to serialize over IPC).
+  Call<PpapiPluginMsg_FileIO_GeneralComplete>(RENDERER,
+      PpapiHostMsg_FileIO_Write(offset, std::string(buffer, bytes_to_write)),
+      base::Bind(&FileIOResource::OnPluginMsgGeneralComplete, this,
+                 temp_callback_));
+  return PP_OK_COMPLETIONPENDING;
+}
+
+int32_t FileIOResource::SetLengthValidated(int64_t length) {
+  Call<PpapiPluginMsg_FileIO_GeneralComplete>(RENDERER,
+      PpapiHostMsg_FileIO_SetLength(length),
+      base::Bind(&FileIOResource::OnPluginMsgGeneralComplete, this,
+                 temp_callback_));
+  return PP_OK_COMPLETIONPENDING;
+}
+
+int32_t FileIOResource::FlushValidated() {
+  Call<PpapiPluginMsg_FileIO_GeneralComplete>(RENDERER,
+      PpapiHostMsg_FileIO_Flush(),
+      base::Bind(&FileIOResource::OnPluginMsgGeneralComplete, this,
+                 temp_callback_));
+  return PP_OK_COMPLETIONPENDING;
+}
+
+void FileIOResource::OnPluginMsgGeneralComplete(
+    scoped_refptr<TrackedCallback> callback,
+    const ResourceMessageReplyParams& params) {
+  DCHECK(pending_op_ == OPERATION_EXCLUSIVE ||
+         pending_op_ == OPERATION_WRITE);
+  callback->Run(params.result());
+  SetOpFinished();
+}
+
+void FileIOResource::OnPluginMsgOpenFileComplete(
+    scoped_refptr<TrackedCallback> callback,
+    const ResourceMessageReplyParams& params) {
+  DCHECK(pending_op_ == OPERATION_EXCLUSIVE);
+  if (params.result() == PP_OK)
+    SetOpenSucceed();
+  callback->Run(params.result());
+  SetOpFinished();
+}
+
+void FileIOResource::OnPluginMsgQueryComplete(
+    scoped_refptr<TrackedCallback> callback,
+    PP_FileInfo* output_info,
+    const ResourceMessageReplyParams& params,
+    const PP_FileInfo& info) {
+  DCHECK(pending_op_ == OPERATION_EXCLUSIVE);
+  *output_info = info;
+  callback->Run(params.result());
+  SetOpFinished();
+}
+
+void FileIOResource::OnPluginMsgReadComplete(
+    scoped_refptr<TrackedCallback> callback,
+    PP_ArrayOutput array_output,
+    const ResourceMessageReplyParams& params,
+    const std::string& data) {
+  DCHECK(pending_op_ == OPERATION_READ);
+
+  // The result code should contain the data size if it's positive.
+  int32_t result = params.result();
+  DCHECK((result < 0 && data.size() == 0) ||
+         result == static_cast<int32_t>(data.size()));
+
+  ArrayWriter output;
+  output.set_pp_array_output(array_output);
+  if (output.is_valid())
+    output.StoreArray(data.data(), std::max(0, result));
+
+  callback->Run(result);
+  SetOpFinished();
+}
+
+void FileIOResource::SetOpInProgress(OperationType new_op) {
+  DCHECK(pending_op_ == OPERATION_NONE ||
+         (pending_op_ != OPERATION_EXCLUSIVE && pending_op_ == new_op));
+  pending_op_ = new_op;
+  num_pending_ops_++;
+}
+
+void FileIOResource::SetOpFinished() {
+  DCHECK(num_pending_ops_ > 0);
+  if (--num_pending_ops_ == 0)
+    pending_op_ = OPERATION_NONE;
+}
+
+}  // namespace proxy
+}  // namespace ppapi