src/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(
  65     net::URLRequest* request,
  66     const net::RedirectInfo& redirect_info,
  67     bool* defer_redirect) {
  68   NOTREACHED();
  69   OnError(base::File::FILE_ERROR_SECURITY);
  70 }
  71
  72 void FileWriterDelegate::OnAuthRequired(net::URLRequest* request,
  73                                         net::AuthChallengeInfo* auth_info) {
  74   NOTREACHED();
  75   OnError(base::File::FILE_ERROR_SECURITY);
  76 }
  77
  78 void FileWriterDelegate::OnCertificateRequested(
  79     net::URLRequest* request,
  80     net::SSLCertRequestInfo* cert_request_info) {
  81   NOTREACHED();
  82   OnError(base::File::FILE_ERROR_SECURITY);
  83 }
  84
  85 void FileWriterDelegate::OnSSLCertificateError(net::URLRequest* request,
  86                                                const net::SSLInfo& ssl_info,
  87                                                bool fatal) {
  88   NOTREACHED();
  89   OnError(base::File::FILE_ERROR_SECURITY);
  90 }
  91
  92 void FileWriterDelegate::OnResponseStarted(net::URLRequest* request) {
  93   DCHECK_EQ(request_.get(), request);
  94   if (!request->status().is_success() || request->GetResponseCode() != 200) {
  95     OnError(base::File::FILE_ERROR_FAILED);
  96     return;
  97   }
  98   Read();
  99 }
 100
 101 void FileWriterDelegate::OnReadCompleted(net::URLRequest* request,
 102                                          int bytes_read) {
 103   DCHECK_EQ(request_.get(), request);
 104   if (!request->status().is_success()) {
 105     OnError(base::File::FILE_ERROR_FAILED);
 106     return;
 107   }
 108   OnDataReceived(bytes_read);
 109 }
 110
 111 void FileWriterDelegate::Read() {
 112   bytes_written_ = 0;
 113   bytes_read_ = 0;
 114   if (request_->Read(io_buffer_.get(), io_buffer_->size(), &bytes_read_)) {
 115     base::MessageLoop::current()->PostTask(
 116         FROM_HERE,
 117         base::Bind(&FileWriterDelegate::OnDataReceived,
 118                    weak_factory_.GetWeakPtr(), bytes_read_));
 119   } else if (!request_->status().is_io_pending()) {
 120     OnError(base::File::FILE_ERROR_FAILED);
 121   }
 122 }
 123
 124 void FileWriterDelegate::OnDataReceived(int bytes_read) {
 125   bytes_read_ = bytes_read;
 126   if (!bytes_read_) {  // We're done.
 127     OnProgress(0, true);
 128   } else {
 129     // This could easily be optimized to rotate between a pool of buffers, so
 130     // that we could read and write at the same time.  It's not yet clear that
 131     // it's necessary.
 132     cursor_ = new net::DrainableIOBuffer(io_buffer_.get(), bytes_read_);
 133     Write();
 134   }
 135 }
 136
 137 void FileWriterDelegate::Write() {
 138   writing_started_ = true;
 139   int64 bytes_to_write = bytes_read_ - bytes_written_;
 140   int write_response =
 141       file_stream_writer_->Write(cursor_.get(),
 142                                  static_cast<int>(bytes_to_write),
 143                                  base::Bind(&FileWriterDelegate::OnDataWritten,
 144                                             weak_factory_.GetWeakPtr()));
 145   if (write_response > 0) {
 146     base::MessageLoop::current()->PostTask(
 147         FROM_HERE,
 148         base::Bind(&FileWriterDelegate::OnDataWritten,
 149                    weak_factory_.GetWeakPtr(), write_response));
 150   } else if (net::ERR_IO_PENDING != write_response) {
 151     OnError(NetErrorToFileError(write_response));
 152   }
 153 }
 154
 155 void FileWriterDelegate::OnDataWritten(int write_response) {
 156   if (write_response > 0) {
 157     OnProgress(write_response, false);
 158     cursor_->DidConsume(write_response);
 159     bytes_written_ += write_response;
 160     if (bytes_written_ == bytes_read_)
 161       Read();
 162     else
 163       Write();
 164   } else {
 165     OnError(NetErrorToFileError(write_response));
 166   }
 167 }
 168
 169 FileWriterDelegate::WriteProgressStatus
 170 FileWriterDelegate::GetCompletionStatusOnError() const {
 171   return writing_started_ ? ERROR_WRITE_STARTED : ERROR_WRITE_NOT_STARTED;
 172 }
 173
 174 void FileWriterDelegate::OnError(base::File::Error error) {
 175   if (request_) {
 176     request_->set_delegate(NULL);
 177     request_->Cancel();
 178   }
 179
 180   if (writing_started_)
 181     MaybeFlushForCompletion(error, 0, ERROR_WRITE_STARTED);
 182   else
 183     write_callback_.Run(error, 0, ERROR_WRITE_NOT_STARTED);
 184 }
 185
 186 void FileWriterDelegate::OnProgress(int bytes_written, bool done) {
 187   DCHECK(bytes_written + bytes_written_backlog_ >= bytes_written_backlog_);
 188   static const int kMinProgressDelayMS = 200;
 189   base::Time currentTime = base::Time::Now();
 190   if (done || last_progress_event_time_.is_null() ||
 191       (currentTime - last_progress_event_time_).InMilliseconds() >
 192           kMinProgressDelayMS) {
 193     bytes_written += bytes_written_backlog_;
 194     last_progress_event_time_ = currentTime;
 195     bytes_written_backlog_ = 0;
 196
 197     if (done) {
 198       MaybeFlushForCompletion(base::File::FILE_OK, bytes_written,
 199                               SUCCESS_COMPLETED);
 200     } else {
 201       write_callback_.Run(base::File::FILE_OK, bytes_written,
 202                           SUCCESS_IO_PENDING);
 203     }
 204     return;
 205   }
 206   bytes_written_backlog_ += bytes_written;
 207 }
 208
 209 void FileWriterDelegate::OnWriteCancelled(int status) {
 210   write_callback_.Run(base::File::FILE_ERROR_ABORT, 0,
 211                       GetCompletionStatusOnError());
 212 }
 213
 214 void FileWriterDelegate::MaybeFlushForCompletion(
 215     base::File::Error error,
 216     int bytes_written,
 217     WriteProgressStatus progress_status) {
 218   if (flush_policy_ == NO_FLUSH_ON_COMPLETION) {
 219     write_callback_.Run(error, bytes_written, progress_status);
 220     return;
 221   }
 222   DCHECK_EQ(FLUSH_ON_COMPLETION, flush_policy_);
 223
 224   int flush_error = file_stream_writer_->Flush(
 225       base::Bind(&FileWriterDelegate::OnFlushed, weak_factory_.GetWeakPtr(),
 226                  error, bytes_written, progress_status));
 227   if (flush_error != net::ERR_IO_PENDING)
 228     OnFlushed(error, bytes_written, progress_status, flush_error);
 229 }
 230
 231 void FileWriterDelegate::OnFlushed(base::File::Error error,
 232                                    int bytes_written,
 233                                    WriteProgressStatus progress_status,
 234                                    int flush_error) {
 235   if (error == base::File::FILE_OK && flush_error != net::OK) {
 236     // If the Flush introduced an error, overwrite the status.
 237     // Otherwise, keep the original error status.
 238     error = NetErrorToFileError(flush_error);
 239     progress_status = GetCompletionStatusOnError();
 240   }
 241   write_callback_.Run(error, bytes_written, progress_status);
 242 }
 243
 244 }  // namespace fileapi