webkit/browser/fileapi/file_writer_delegate.cc

   1 // Copyright (c) 2012 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 "webkit/browser/fileapi/file_writer_delegate.h"
   6
   7 #include "base/bind.h"
   8 #include "base/callback.h"
   9 #include "base/files/file_util_proxy.h"
  10 #include "base/message_loop/message_loop.h"
  11 #include "base/message_loop/message_loop_proxy.h"
  12 #include "base/sequenced_task_runner.h"
  13 #include "base/threading/thread_restrictions.h"
  14 #include "net/base/net_errors.h"
  15 #include "webkit/browser/fileapi/file_stream_writer.h"
  16 #include "webkit/browser/fileapi/file_system_context.h"
  17 #include "webkit/common/fileapi/file_system_util.h"
  18
  19 namespace fileapi {
  20
  21 static const int kReadBufSize = 32768;
  22
  23 FileWriterDelegate::FileWriterDelegate(
  24     scoped_ptr<FileStreamWriter> file_stream_writer,
  25     FlushPolicy flush_policy)
  26     : file_stream_writer_(file_stream_writer.Pass()),
  27       writing_started_(false),
  28       flush_policy_(flush_policy),
  29       bytes_written_backlog_(0),
  30       bytes_written_(0),
  31       bytes_read_(0),
  32       io_buffer_(new net::IOBufferWithSize(kReadBufSize)),
  33       weak_factory_(this) {
  34 }
  35
  36 FileWriterDelegate::~FileWriterDelegate() {
  37 }
  38
  39 void FileWriterDelegate::Start(scoped_ptr<net::URLRequest> request,
  40                                const DelegateWriteCallback& write_callback) {
  41   write_callback_ = write_callback;
  42   request_ = request.Pass();
  43   request_->Start();
  44 }
  45
  46 void FileWriterDelegate::Cancel() {
  47   if (request_) {
  48     // This halts any callbacks on this delegate.
  49     request_->set_delegate(NULL);
  50     request_->Cancel();
  51   }
  52
  53   const int status = file_stream_writer_->Cancel(
  54       base::Bind(&FileWriterDelegate::OnWriteCancelled,
  55                  weak_factory_.GetWeakPtr()));
  56   // Return true to finish immediately if we have no pending writes.
  57   // Otherwise we'll do the final cleanup in the Cancel callback.
  58   if (status != net::ERR_IO_PENDING) {
  59     write_callback_.Run(base::File::FILE_ERROR_ABORT, 0,
  60                         GetCompletionStatusOnError());
  61   }
  62 }
  63
  64 void FileWriterDelegate::OnReceivedRedirect(net::URLRequest* request,
  65                                             const GURL& new_url,
  66                                             bool* defer_redirect) {
  67   NOTREACHED();
  68   OnError(base::File::FILE_ERROR_SECURITY);
  69 }
  70
  71 void FileWriterDelegate::OnAuthRequired(net::URLRequest* request,
  72                                         net::AuthChallengeInfo* auth_info) {
  73   NOTREACHED();
  74   OnError(base::File::FILE_ERROR_SECURITY);
  75 }
  76
  77 void FileWriterDelegate::OnCertificateRequested(
  78     net::URLRequest* request,
  79     net::SSLCertRequestInfo* cert_request_info) {
  80   NOTREACHED();
  81   OnError(base::File::FILE_ERROR_SECURITY);
  82 }
  83
  84 void FileWriterDelegate::OnSSLCertificateError(net::URLRequest* request,
  85                                                const net::SSLInfo& ssl_info,
  86                                                bool fatal) {
  87   NOTREACHED();
  88   OnError(base::File::FILE_ERROR_SECURITY);
  89 }
  90
  91 void FileWriterDelegate::OnResponseStarted(net::URLRequest* request) {
  92   DCHECK_EQ(request_.get(), request);
  93   if (!request->status().is_success() || request->GetResponseCode() != 200) {
  94     OnError(base::File::FILE_ERROR_FAILED);
  95     return;
  96   }
  97   Read();
  98 }
  99
 100 void FileWriterDelegate::OnReadCompleted(net::URLRequest* request,
 101                                          int bytes_read) {
 102   DCHECK_EQ(request_.get(), request);
 103   if (!request->status().is_success()) {
 104     OnError(base::File::FILE_ERROR_FAILED);
 105     return;
 106   }
 107   OnDataReceived(bytes_read);
 108 }
 109
 110 void FileWriterDelegate::Read() {
 111   bytes_written_ = 0;
 112   bytes_read_ = 0;
 113   if (request_->Read(io_buffer_.get(), io_buffer_->size(), &bytes_read_)) {
 114     base::MessageLoop::current()->PostTask(
 115         FROM_HERE,
 116         base::Bind(&FileWriterDelegate::OnDataReceived,
 117                    weak_factory_.GetWeakPtr(), bytes_read_));
 118   } else if (!request_->status().is_io_pending()) {
 119     OnError(base::File::FILE_ERROR_FAILED);
 120   }
 121 }
 122
 123 void FileWriterDelegate::OnDataReceived(int bytes_read) {
 124   bytes_read_ = bytes_read;
 125   if (!bytes_read_) {  // We're done.
 126     OnProgress(0, true);
 127   } else {
 128     // This could easily be optimized to rotate between a pool of buffers, so
 129     // that we could read and write at the same time.  It's not yet clear that
 130     // it's necessary.
 131     cursor_ = new net::DrainableIOBuffer(io_buffer_.get(), bytes_read_);
 132     Write();
 133   }
 134 }
 135
 136 void FileWriterDelegate::Write() {
 137   writing_started_ = true;
 138   int64 bytes_to_write = bytes_read_ - bytes_written_;
 139   int write_response =
 140       file_stream_writer_->Write(cursor_.get(),
 141                                  static_cast<int>(bytes_to_write),
 142                                  base::Bind(&FileWriterDelegate::OnDataWritten,
 143                                             weak_factory_.GetWeakPtr()));
 144   if (write_response > 0) {
 145     base::MessageLoop::current()->PostTask(
 146         FROM_HERE,
 147         base::Bind(&FileWriterDelegate::OnDataWritten,
 148                    weak_factory_.GetWeakPtr(), write_response));
 149   } else if (net::ERR_IO_PENDING != write_response) {
 150     OnError(NetErrorToFileError(write_response));
 151   }
 152 }
 153
 154 void FileWriterDelegate::OnDataWritten(int write_response) {
 155   if (write_response > 0) {
 156     OnProgress(write_response, false);
 157     cursor_->DidConsume(write_response);
 158     bytes_written_ += write_response;
 159     if (bytes_written_ == bytes_read_)
 160       Read();
 161     else
 162       Write();
 163   } else {
 164     OnError(NetErrorToFileError(write_response));
 165   }
 166 }
 167
 168 FileWriterDelegate::WriteProgressStatus
 169 FileWriterDelegate::GetCompletionStatusOnError() const {
 170   return writing_started_ ? ERROR_WRITE_STARTED : ERROR_WRITE_NOT_STARTED;
 171 }
 172
 173 void FileWriterDelegate::OnError(base::File::Error error) {
 174   if (request_) {
 175     request_->set_delegate(NULL);
 176     request_->Cancel();
 177   }
 178
 179   if (writing_started_)
 180     MaybeFlushForCompletion(error, 0, ERROR_WRITE_STARTED);
 181   else
 182     write_callback_.Run(error, 0, ERROR_WRITE_NOT_STARTED);
 183 }
 184
 185 void FileWriterDelegate::OnProgress(int bytes_written, bool done) {
 186   DCHECK(bytes_written + bytes_written_backlog_ >= bytes_written_backlog_);
 187   static const int kMinProgressDelayMS = 200;
 188   base::Time currentTime = base::Time::Now();
 189   if (done || last_progress_event_time_.is_null() ||
 190       (currentTime - last_progress_event_time_).InMilliseconds() >
 191           kMinProgressDelayMS) {
 192     bytes_written += bytes_written_backlog_;
 193     last_progress_event_time_ = currentTime;
 194     bytes_written_backlog_ = 0;
 195
 196     if (done) {
 197       MaybeFlushForCompletion(base::File::FILE_OK, bytes_written,
 198                               SUCCESS_COMPLETED);
 199     } else {
 200       write_callback_.Run(base::File::FILE_OK, bytes_written,
 201                           SUCCESS_IO_PENDING);
 202     }
 203     return;
 204   }
 205   bytes_written_backlog_ += bytes_written;
 206 }
 207
 208 void FileWriterDelegate::OnWriteCancelled(int status) {
 209   write_callback_.Run(base::File::FILE_ERROR_ABORT, 0,
 210                       GetCompletionStatusOnError());
 211 }
 212
 213 void FileWriterDelegate::MaybeFlushForCompletion(
 214     base::File::Error error,
 215     int bytes_written,
 216     WriteProgressStatus progress_status) {
 217   if (flush_policy_ == NO_FLUSH_ON_COMPLETION) {
 218     write_callback_.Run(error, bytes_written, progress_status);
 219     return;
 220   }
 221   DCHECK_EQ(FLUSH_ON_COMPLETION, flush_policy_);
 222
 223   int flush_error = file_stream_writer_->Flush(
 224       base::Bind(&FileWriterDelegate::OnFlushed, weak_factory_.GetWeakPtr(),
 225                  error, bytes_written, progress_status));
 226   if (flush_error != net::ERR_IO_PENDING)
 227     OnFlushed(error, bytes_written, progress_status, flush_error);
 228 }
 229
 230 void FileWriterDelegate::OnFlushed(base::File::Error error,
 231                                    int bytes_written,
 232                                    WriteProgressStatus progress_status,
 233                                    int flush_error) {
 234   if (error == base::File::FILE_OK && flush_error != net::OK) {
 235     // If the Flush introduced an error, overwrite the status.
 236     // Otherwise, keep the original error status.
 237     error = NetErrorToFileError(flush_error);
 238     progress_status = GetCompletionStatusOnError();
 239   }
 240   write_callback_.Run(error, bytes_written, progress_status);
 241 }
 242
 243 }  // namespace fileapi