chrome/browser/local_discovery/pwg_raster_converter.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/local_discovery/pwg_raster_converter.h"
   6
   7 #include "base/bind_helpers.h"
   8 #include "base/cancelable_callback.h"
   9 #include "base/file_util.h"
  10 #include "base/files/file.h"
  11 #include "base/files/scoped_temp_dir.h"
  12 #include "base/logging.h"
  13 #include "chrome/common/chrome_utility_messages.h"
  14 #include "content/public/browser/browser_thread.h"
  15 #include "content/public/browser/child_process_data.h"
  16 #include "content/public/browser/utility_process_host.h"
  17 #include "content/public/browser/utility_process_host_client.h"
  18
  19 namespace local_discovery {
  20
  21 namespace {
  22
  23 using content::BrowserThread;
  24
  25 class FileHandlers {
  26  public:
  27   FileHandlers() {}
  28
  29   ~FileHandlers() {
  30     DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
  31   }
  32
  33   void Init(base::RefCountedMemory* data);
  34   bool IsValid();
  35
  36   base::FilePath GetPwgPath() const {
  37     return temp_dir_.path().AppendASCII("output.pwg");
  38   }
  39
  40   base::FilePath GetPdfPath() const {
  41     return temp_dir_.path().AppendASCII("input.pdf");
  42   }
  43
  44   IPC::PlatformFileForTransit GetPdfForProcess(base::ProcessHandle process) {
  45     DCHECK(pdf_file_.IsValid());
  46     IPC::PlatformFileForTransit transit =
  47         IPC::TakeFileHandleForProcess(pdf_file_.Pass(), process);
  48     return transit;
  49   }
  50
  51   IPC::PlatformFileForTransit GetPwgForProcess(base::ProcessHandle process) {
  52     DCHECK(pwg_file_.IsValid());
  53     IPC::PlatformFileForTransit transit =
  54         IPC::TakeFileHandleForProcess(pwg_file_.Pass(), process);
  55     return transit;
  56   }
  57
  58  private:
  59   base::ScopedTempDir temp_dir_;
  60   base::File pdf_file_;
  61   base::File pwg_file_;
  62 };
  63
  64 void FileHandlers::Init(base::RefCountedMemory* data) {
  65   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
  66
  67   if (!temp_dir_.CreateUniqueTempDir()) {
  68     return;
  69   }
  70
  71   if (static_cast<int>(data->size()) !=
  72       base::WriteFile(GetPdfPath(), data->front_as<char>(), data->size())) {
  73     return;
  74   }
  75
  76   // Reopen in read only mode.
  77   pdf_file_.Initialize(GetPdfPath(),
  78                        base::File::FLAG_OPEN | base::File::FLAG_READ);
  79   pwg_file_.Initialize(
  80       GetPwgPath(),
  81       base::File::FLAG_CREATE_ALWAYS | base::File::FLAG_APPEND);
  82 }
  83
  84 bool FileHandlers::IsValid() {
  85   return pdf_file_.IsValid() && pwg_file_.IsValid();
  86 }
  87
  88 // Converts PDF into PWG raster.
  89 // Class uses 3 threads: UI, IO and FILE.
  90 // Internal workflow is following:
  91 // 1. Create instance on the UI thread. (files_, settings_,)
  92 // 2. Create file on the FILE thread.
  93 // 3. Start utility process and start conversion on the IO thread.
  94 // 4. Run result callback on the UI thread.
  95 // 5. Instance is destroyed from any thread that has the last reference.
  96 // 6. FileHandlers destroyed on the FILE thread.
  97 //    This step posts |FileHandlers| to be destroyed on the FILE thread.
  98 // All these steps work sequentially, so no data should be accessed
  99 // simultaneously by several threads.
 100 class PwgUtilityProcessHostClient : public content::UtilityProcessHostClient {
 101  public:
 102   explicit PwgUtilityProcessHostClient(
 103       const printing::PdfRenderSettings& settings,
 104       const printing::PwgRasterSettings& bitmap_settings);
 105
 106   void Convert(base::RefCountedMemory* data,
 107                const PWGRasterConverter::ResultCallback& callback);
 108
 109   // UtilityProcessHostClient implementation.
 110   virtual void OnProcessCrashed(int exit_code) OVERRIDE;
 111   virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE;
 112
 113  private:
 114   virtual ~PwgUtilityProcessHostClient();
 115
 116   // Message handlers.
 117   void OnProcessStarted();
 118   void OnSucceeded();
 119   void OnFailed();
 120
 121   void RunCallback(bool success);
 122
 123   void StartProcessOnIOThread();
 124
 125   void RunCallbackOnUIThread(bool success);
 126   void OnFilesReadyOnUIThread();
 127
 128   scoped_ptr<FileHandlers> files_;
 129   printing::PdfRenderSettings settings_;
 130   printing::PwgRasterSettings bitmap_settings_;
 131   PWGRasterConverter::ResultCallback callback_;
 132   base::WeakPtr<content::UtilityProcessHost> utility_process_host_;
 133
 134   DISALLOW_COPY_AND_ASSIGN(PwgUtilityProcessHostClient);
 135 };
 136
 137 PwgUtilityProcessHostClient::PwgUtilityProcessHostClient(
 138     const printing::PdfRenderSettings& settings,
 139     const printing::PwgRasterSettings& bitmap_settings)
 140     : settings_(settings), bitmap_settings_(bitmap_settings) {}
 141
 142 PwgUtilityProcessHostClient::~PwgUtilityProcessHostClient() {
 143   // Delete temp directory.
 144   BrowserThread::DeleteSoon(BrowserThread::FILE, FROM_HERE, files_.release());
 145 }
 146
 147 void PwgUtilityProcessHostClient::Convert(
 148     base::RefCountedMemory* data,
 149     const PWGRasterConverter::ResultCallback& callback) {
 150   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 151   callback_ = callback;
 152   CHECK(!files_);
 153   files_.reset(new FileHandlers());
 154   BrowserThread::PostTaskAndReply(
 155       BrowserThread::FILE, FROM_HERE,
 156       base::Bind(&FileHandlers::Init, base::Unretained(files_.get()),
 157                  make_scoped_refptr(data)),
 158       base::Bind(&PwgUtilityProcessHostClient::OnFilesReadyOnUIThread, this));
 159 }
 160
 161 void PwgUtilityProcessHostClient::OnProcessCrashed(int exit_code) {
 162   OnFailed();
 163 }
 164
 165 bool PwgUtilityProcessHostClient::OnMessageReceived(
 166   const IPC::Message& message) {
 167   bool handled = true;
 168   IPC_BEGIN_MESSAGE_MAP(PwgUtilityProcessHostClient, message)
 169     IPC_MESSAGE_HANDLER(ChromeUtilityHostMsg_ProcessStarted, OnProcessStarted)
 170     IPC_MESSAGE_HANDLER(
 171         ChromeUtilityHostMsg_RenderPDFPagesToPWGRaster_Succeeded, OnSucceeded)
 172     IPC_MESSAGE_HANDLER(ChromeUtilityHostMsg_RenderPDFPagesToPWGRaster_Failed,
 173                         OnFailed)
 174     IPC_MESSAGE_UNHANDLED(handled = false)
 175   IPC_END_MESSAGE_MAP()
 176   return handled;
 177 }
 178
 179 void PwgUtilityProcessHostClient::OnProcessStarted() {
 180   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 181   if (!utility_process_host_) {
 182     RunCallbackOnUIThread(false);
 183     return;
 184   }
 185
 186   base::ProcessHandle process = utility_process_host_->GetData().handle;
 187   utility_process_host_->Send(new ChromeUtilityMsg_RenderPDFPagesToPWGRaster(
 188       files_->GetPdfForProcess(process),
 189       settings_,
 190       bitmap_settings_,
 191       files_->GetPwgForProcess(process)));
 192   utility_process_host_.reset();
 193 }
 194
 195 void PwgUtilityProcessHostClient::OnSucceeded() {
 196   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 197   RunCallback(true);
 198 }
 199
 200 void PwgUtilityProcessHostClient::OnFailed() {
 201   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 202   RunCallback(false);
 203 }
 204
 205 void PwgUtilityProcessHostClient::OnFilesReadyOnUIThread() {
 206   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 207   if (!files_->IsValid()) {
 208     RunCallbackOnUIThread(false);
 209     return;
 210   }
 211   BrowserThread::PostTask(
 212       BrowserThread::IO, FROM_HERE,
 213       base::Bind(&PwgUtilityProcessHostClient::StartProcessOnIOThread, this));
 214 }
 215
 216 void PwgUtilityProcessHostClient::StartProcessOnIOThread() {
 217   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 218   utility_process_host_ =
 219       content::UtilityProcessHost::Create(
 220           this,
 221           base::MessageLoop::current()->message_loop_proxy())->AsWeakPtr();
 222   utility_process_host_->Send(new ChromeUtilityMsg_StartupPing);
 223 }
 224
 225 void PwgUtilityProcessHostClient::RunCallback(bool success) {
 226   BrowserThread::PostTask(
 227       BrowserThread::UI, FROM_HERE,
 228       base::Bind(&PwgUtilityProcessHostClient::RunCallbackOnUIThread, this,
 229                  success));
 230 }
 231
 232 void PwgUtilityProcessHostClient::RunCallbackOnUIThread(bool success) {
 233   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 234   if (!callback_.is_null()) {
 235     BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
 236                             base::Bind(callback_, success,
 237                                        files_->GetPwgPath()));
 238     callback_.Reset();
 239   }
 240 }
 241
 242 class PWGRasterConverterImpl : public PWGRasterConverter {
 243  public:
 244   PWGRasterConverterImpl();
 245
 246   virtual ~PWGRasterConverterImpl();
 247
 248   virtual void Start(base::RefCountedMemory* data,
 249                      const printing::PdfRenderSettings& conversion_settings,
 250                      const printing::PwgRasterSettings& bitmap_settings,
 251                      const ResultCallback& callback) OVERRIDE;
 252
 253  private:
 254   scoped_refptr<PwgUtilityProcessHostClient> utility_client_;
 255   base::CancelableCallback<ResultCallback::RunType> callback_;
 256
 257   DISALLOW_COPY_AND_ASSIGN(PWGRasterConverterImpl);
 258 };
 259
 260 PWGRasterConverterImpl::PWGRasterConverterImpl() {
 261 }
 262
 263 PWGRasterConverterImpl::~PWGRasterConverterImpl() {
 264 }
 265
 266 void PWGRasterConverterImpl::Start(
 267     base::RefCountedMemory* data,
 268     const printing::PdfRenderSettings& conversion_settings,
 269     const printing::PwgRasterSettings& bitmap_settings,
 270     const ResultCallback& callback) {
 271   // Rebind cancelable callback to avoid calling callback if
 272   // PWGRasterConverterImpl is destroyed.
 273   callback_.Reset(callback);
 274   utility_client_ =
 275       new PwgUtilityProcessHostClient(conversion_settings, bitmap_settings);
 276   utility_client_->Convert(data, callback_.callback());
 277 }
 278
 279 }  // namespace
 280
 281 // static
 282 scoped_ptr<PWGRasterConverter> PWGRasterConverter::CreateDefault() {
 283   return scoped_ptr<PWGRasterConverter>(new PWGRasterConverterImpl());
 284 }
 285
 286 }  // namespace local_discovery