electron/atom/browser/atom_blob_reader.cc

124 lines
4.1 KiB
C++

// Copyright (c) 2016 GitHub, Inc.
// Use of this source code is governed by the MIT license that can be
// found in the LICENSE file.
#include "atom/browser/atom_blob_reader.h"
#include "content/browser/blob_storage/chrome_blob_storage_context.h"
#include "content/public/browser/browser_thread.h"
#include "net/base/io_buffer.h"
#include "net/base/net_errors.h"
#include "storage/browser/blob/blob_data_handle.h"
#include "storage/browser/blob/blob_reader.h"
#include "storage/browser/blob/blob_storage_context.h"
#include "storage/browser/fileapi/file_system_context.h"
#include "atom/common/node_includes.h"
using content::BrowserThread;
namespace atom {
namespace {
void FreeNodeBufferData(char* data, void* hint) {
delete[] data;
}
void RunCallbackInUI(const AtomBlobReader::CompletionCallback& callback,
char* blob_data,
int size) {
DCHECK_CURRENTLY_ON(BrowserThread::UI);
v8::Isolate* isolate = v8::Isolate::GetCurrent();
v8::Locker locker(isolate);
v8::HandleScope handle_scope(isolate);
if (blob_data) {
v8::Local<v8::Value> buffer =
node::Buffer::New(isolate, blob_data, static_cast<size_t>(size),
&FreeNodeBufferData, nullptr)
.ToLocalChecked();
callback.Run(buffer);
} else {
callback.Run(v8::Null(isolate));
}
}
} // namespace
AtomBlobReader::AtomBlobReader(content::ChromeBlobStorageContext* blob_context,
storage::FileSystemContext* file_system_context)
: blob_context_(blob_context), file_system_context_(file_system_context) {}
AtomBlobReader::~AtomBlobReader() {}
void AtomBlobReader::StartReading(
const std::string& uuid,
const AtomBlobReader::CompletionCallback& completion_callback) {
DCHECK_CURRENTLY_ON(BrowserThread::IO);
auto blob_data_handle = blob_context_->context()->GetBlobDataFromUUID(uuid);
auto callback = base::Bind(&RunCallbackInUI, completion_callback);
if (!blob_data_handle) {
BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
base::BindOnce(callback, nullptr, 0));
return;
}
auto blob_reader = blob_data_handle->CreateReader(file_system_context_.get());
BlobReadHelper* blob_read_helper =
new BlobReadHelper(std::move(blob_reader), callback);
blob_read_helper->Read();
}
AtomBlobReader::BlobReadHelper::BlobReadHelper(
std::unique_ptr<storage::BlobReader> blob_reader,
const BlobReadHelper::CompletionCallback& callback)
: blob_reader_(std::move(blob_reader)), completion_callback_(callback) {}
AtomBlobReader::BlobReadHelper::~BlobReadHelper() {}
void AtomBlobReader::BlobReadHelper::Read() {
DCHECK_CURRENTLY_ON(BrowserThread::IO);
storage::BlobReader::Status size_status = blob_reader_->CalculateSize(
base::Bind(&AtomBlobReader::BlobReadHelper::DidCalculateSize,
base::Unretained(this)));
if (size_status != storage::BlobReader::Status::IO_PENDING)
DidCalculateSize(net::OK);
}
void AtomBlobReader::BlobReadHelper::DidCalculateSize(int result) {
DCHECK_CURRENTLY_ON(BrowserThread::IO);
if (result != net::OK) {
DidReadBlobData(nullptr, 0);
return;
}
uint64_t total_size = blob_reader_->total_size();
int bytes_read = 0;
scoped_refptr<net::IOBuffer> blob_data =
new net::IOBuffer(static_cast<size_t>(total_size));
auto callback =
base::Bind(&AtomBlobReader::BlobReadHelper::DidReadBlobData,
base::Unretained(this), base::RetainedRef(blob_data));
storage::BlobReader::Status read_status =
blob_reader_->Read(blob_data.get(), total_size, &bytes_read, callback);
if (read_status != storage::BlobReader::Status::IO_PENDING)
callback.Run(bytes_read);
}
void AtomBlobReader::BlobReadHelper::DidReadBlobData(
const scoped_refptr<net::IOBuffer>& blob_data,
int size) {
DCHECK_CURRENTLY_ON(BrowserThread::IO);
char* data = new char[size];
memcpy(data, blob_data->data(), size);
BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
base::BindOnce(completion_callback_, data, size));
delete this;
}
} // namespace atom