1// Copyright 2013 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#include "chrome/browser/extensions/blob_reader.h"
6
7#include "base/format_macros.h"
8#include "base/strings/string_util.h"
9#include "base/strings/stringprintf.h"
10#include "chrome/browser/profiles/profile.h"
11#include "content/public/browser/browser_thread.h"
12#include "net/http/http_request_headers.h"
13#include "net/http/http_response_headers.h"
14#include "net/url_request/url_fetcher.h"
15#include "net/url_request/url_request_context.h"
16#include "net/url_request/url_request_context_getter.h"
17
18BlobReader::BlobReader(Profile* profile,
19                       const std::string& blob_uuid,
20                       BlobReadCallback callback)
21    : callback_(callback) {
22  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
23  GURL blob_url;
24  if (StartsWithASCII(blob_uuid, "blob:blobinternal", true)) {
25    // TODO(michaeln): remove support for deprecated blob urls
26    blob_url = GURL(blob_uuid);
27  } else {
28    blob_url = GURL(std::string("blob:uuid/") + blob_uuid);
29  }
30  DCHECK(blob_url.is_valid());
31  fetcher_.reset(net::URLFetcher::Create(
32      blob_url, net::URLFetcher::GET,
33      this));
34  fetcher_->SetRequestContext(profile->GetRequestContext());
35}
36
37BlobReader::~BlobReader() { DCHECK_CURRENTLY_ON(content::BrowserThread::UI); }
38
39void BlobReader::SetByteRange(int64 offset, int64 length) {
40  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
41  CHECK_GE(offset, 0);
42  CHECK_GT(length, 0);
43  CHECK_LE(offset, kint64max - length);
44
45  net::HttpRequestHeaders headers;
46  headers.SetHeader(
47      net::HttpRequestHeaders::kRange,
48      base::StringPrintf("bytes=%" PRId64 "-%" PRId64, offset,
49                         offset + length - 1));
50  fetcher_->SetExtraRequestHeaders(headers.ToString());
51}
52
53void BlobReader::Start() {
54  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
55  fetcher_->Start();
56}
57
58// Overridden from net::URLFetcherDelegate.
59void BlobReader::OnURLFetchComplete(const net::URLFetcher* source) {
60  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
61  scoped_ptr<std::string> response(new std::string);
62  int64 first = 0, last = 0, length = 0;
63  source->GetResponseAsString(response.get());
64  source->GetResponseHeaders()->GetContentRange(&first, &last, &length);
65  callback_.Run(response.Pass(), length);
66
67  delete this;
68}
69