blob: b01a21a06dcaddff90520c952cb93157ed652fc2 [file] [log] [blame]
/*
* Copyright 2015 Google Inc. All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "cobalt/loader/loader.h"
#include "base/bind.h"
#include "base/compiler_specific.h"
#include "base/logging.h"
#include "base/message_loop.h"
namespace cobalt {
namespace loader {
//////////////////////////////////////////////////////////////////
// Loader::FetcherToDecoderAdapter
//////////////////////////////////////////////////////////////////
// This class is responsible for passing chunks of data from fetcher to
// decoder and notifying fetching is done or aborted on error.
class Loader::FetcherToDecoderAdapter : public Fetcher::Handler {
public:
FetcherToDecoderAdapter(
Decoder* decoder, base::Callback<void(const std::string&)> error_callback)
: decoder_(decoder), error_callback_(error_callback) {}
// From Fetcher::Handler.
LoadResponseType OnResponseStarted(
Fetcher* fetcher,
const scoped_refptr<net::HttpResponseHeaders>& headers) OVERRIDE {
if (headers) {
return decoder_->OnResponseStarted(fetcher, headers);
} else {
return kLoadResponseContinue;
}
}
void OnReceived(Fetcher* fetcher, const char* data, size_t size) OVERRIDE {
UNREFERENCED_PARAMETER(fetcher);
decoder_->DecodeChunk(data, size);
}
void OnReceivedPassed(Fetcher* fetcher,
scoped_ptr<std::string> data) OVERRIDE {
UNREFERENCED_PARAMETER(fetcher);
decoder_->DecodeChunkPassed(data.Pass());
}
void OnDone(Fetcher* fetcher) OVERRIDE {
UNREFERENCED_PARAMETER(fetcher);
decoder_->Finish();
}
void OnError(Fetcher* fetcher, const std::string& error) OVERRIDE {
UNREFERENCED_PARAMETER(fetcher);
error_callback_.Run(error);
}
private:
Decoder* decoder_;
base::Callback<void(const std::string&)> error_callback_;
};
//////////////////////////////////////////////////////////////////
// Loader
//////////////////////////////////////////////////////////////////
Loader::Loader(const FetcherCreator& fetcher_creator,
scoped_ptr<Decoder> decoder, const OnErrorFunction& on_error,
const OnDestructionFunction& on_destruction)
: fetcher_creator_(fetcher_creator),
decoder_(decoder.Pass()),
on_error_(on_error),
on_destruction_(on_destruction),
suspended_(false) {
DCHECK(decoder_);
DCHECK(!on_error.is_null());
Start();
// Post the error callback on the current message loop in case loader is
// destroyed in the callback.
if (!fetcher_) {
fetcher_creator_error_closure_.Reset(
base::Bind(on_error, "Fetcher was not created."));
MessageLoop::current()->PostTask(FROM_HERE,
fetcher_creator_error_closure_.callback());
}
}
Loader::~Loader() {
if (!on_destruction_.is_null()) {
on_destruction_.Run(this);
}
DCHECK(thread_checker_.CalledOnValidThread());
fetcher_creator_error_closure_.Cancel();
}
void Loader::Suspend() {
DCHECK(thread_checker_.CalledOnValidThread());
if (suspended_) {
return;
}
bool suspendable = decoder_->Suspend();
if (fetcher_) {
fetcher_.reset();
}
fetcher_to_decoder_adaptor_.reset();
fetcher_creator_error_closure_.Cancel();
suspended_ = true;
if (!suspendable) {
on_error_.Run("Aborted.");
}
}
void Loader::Resume(render_tree::ResourceProvider* resource_provider) {
DCHECK(thread_checker_.CalledOnValidThread());
if (!suspended_) {
return;
}
suspended_ = false;
decoder_->Resume(resource_provider);
Start();
}
void Loader::Start() {
DCHECK(thread_checker_.CalledOnValidThread());
DCHECK(decoder_);
DCHECK(!fetcher_creator_.is_null());
fetcher_to_decoder_adaptor_.reset(
new FetcherToDecoderAdapter(decoder_.get(), on_error_));
fetcher_ = fetcher_creator_.Run(fetcher_to_decoder_adaptor_.get());
}
} // namespace loader
} // namespace cobalt