Decompress credits page on iOS

ios/chrome/browser/ui/webui/about_ui.cc

 // Copyright 2015 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 "ios/chrome/browser/ui/webui/about_ui.h"
 
 #include <algorithm>
 #include <string>
 #include <utility>
 #include <vector>
 
 #include "base/format_macros.h"
 #include "base/i18n/number_formatting.h"
 #include "base/macros.h"
 #include "base/metrics/statistics_recorder.h"
 #include "base/strings/string_number_conversions.h"
 #include "components/grit/components_resources.h"
 #include "google_apis/gaia/google_service_auth_error.h"
 #include "ios/chrome/browser/browser_state/chrome_browser_state.h"
 #include "ios/chrome/browser/chrome_url_constants.h"
 #include "ios/web/public/url_data_source_ios.h"
 #include "net/base/escape.h"
+#include "third_party/brotli/dec/decode.h"
 #include "ui/base/device_form_factor.h"
 #include "ui/base/resource/resource_bundle.h"
 #include "url/gurl.h"
 
 namespace {
 
 const char kCreditsJsPath[] = "credits.js";
 const char kStringsJsPath[] = "strings.js";
 
 class AboutUIHTMLSource : public web::URLDataSourceIOS {
@@ skipping 86 matching lines @@
     const std::string& path,
     const web::URLDataSourceIOS::GotDataCallback& callback) {
   std::string response;
   // Add your data source here, in alphabetical order.
   if (source_name_ == kChromeUIChromeURLsHost) {
     response = ChromeURLs();
   } else if (source_name_ == kChromeUICreditsHost) {
     int idr = IDR_ABOUT_UI_CREDITS_HTML;
     if (path == kCreditsJsPath)
       idr = IDR_ABOUT_UI_CREDITS_JS;
-    response =
-        ResourceBundle::GetSharedInstance().GetRawDataResource(idr).as_string();
+    base::StringPiece raw_response =
+        ResourceBundle::GetSharedInstance().GetRawDataResource(idr);
+    if (idr == IDR_ABOUT_UI_CREDITS_HTML) {
+      size_t decoded_size;
+      const uint8_t* encoded_response_buffer =
+          reinterpret_cast<const uint8_t*>(raw_response.data());
+      CHECK(BrotliDecompressedSize(raw_response.size(), encoded_response_buffer,
+                                   &decoded_size));
+      // Resizing the response and using it as the buffer Brotli decompresses
+      // into.
+      response.resize(decoded_size);
+      CHECK(BrotliDecompressBuffer(raw_response.size(), encoded_response_buffer,
+                                   &decoded_size,
+                                   reinterpret_cast<uint8_t*>(&response[0])) ==
+            BROTLI_RESULT_SUCCESS);
+    } else {
+      response = raw_response.as_string();
+    }
   } else if (source_name_ == kChromeUIHistogramHost) {
     // Note: On other platforms, this is implemented in //content. If there is
     // ever a need for embedders other than //ios/chrome to use
     // chrome://histograms, this code could likely be moved to //io/web.
     base::StatisticsRecorder::WriteHTMLGraph("", &response);
   }
 
   FinishDataRequest(response, callback);
 }
 
@@ skipping 15 matching lines @@
   return web::URLDataSourceIOS::ShouldDenyXFrameOptions();
 }
 
 AboutUI::AboutUI(web::WebUIIOS* web_ui, const std::string& name)
     : web::WebUIIOSController(web_ui) {
   web::URLDataSourceIOS::Add(ios::ChromeBrowserState::FromWebUIIOS(web_ui),
                              new AboutUIHTMLSource(name));
 }
 
 AboutUI::~AboutUI() {}