chrome/browser/extensions/blob_reader.cc

   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 "net/http/http_request_headers.h"
  12 #include "net/http/http_response_headers.h"
  13 #include "net/url_request/url_fetcher.h"
  14 #include "net/url_request/url_request_context.h"
  15 #include "net/url_request/url_request_context_getter.h"
  16
  17 BlobReader::BlobReader(Profile* profile,
  18                        const std::string& blob_uuid,
  19                        BlobReadCallback callback)
  20     : callback_(callback) {
  21   GURL blob_url;
  22   if (StartsWithASCII(blob_uuid, "blob:blobinternal", true)) {
  23     // TODO(michaeln): remove support for deprecated blob urls
  24     blob_url = GURL(blob_uuid);
  25   } else {
  26     blob_url = GURL(std::string("blob:uuid/") + blob_uuid);
  27   }
  28   DCHECK(blob_url.is_valid());
  29   fetcher_.reset(net::URLFetcher::Create(
  30       blob_url, net::URLFetcher::GET,
  31       this));
  32   fetcher_->SetRequestContext(profile->GetRequestContext());
  33 }
  34
  35 BlobReader::~BlobReader() {
  36 }
  37
  38 void BlobReader::SetByteRange(int64 offset, int64 length) {
  39   CHECK_GE(offset, 0);
  40   CHECK_GT(length, 0);
  41   CHECK_LE(offset, kint64max - length);
  42
  43   net::HttpRequestHeaders headers;
  44   headers.SetHeader(
  45       net::HttpRequestHeaders::kRange,
  46       base::StringPrintf("bytes=%" PRId64 "-%" PRId64, offset,
  47                          offset + length - 1));
  48   fetcher_->SetExtraRequestHeaders(headers.ToString());
  49 }
  50
  51 void BlobReader::Start() {
  52   fetcher_->Start();
  53 }
  54
  55 // Overridden from net::URLFetcherDelegate.
  56 void BlobReader::OnURLFetchComplete(const net::URLFetcher* source) {
  57   scoped_ptr<std::string> response(new std::string);
  58   int64 first = 0, last = 0, length = 0;
  59   source->GetResponseAsString(response.get());
  60   source->GetResponseHeaders()->GetContentRange(&first, &last, &length);
  61   callback_.Run(response.Pass(), length);
  62
  63   delete this;
  64 }