net/base/file_stream_context_win.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 "net/base/file_stream_context.h"
   6
   7 #include <windows.h>
   8
   9 #include "base/files/file_path.h"
  10 #include "base/logging.h"
  11 #include "base/message_loop/message_loop.h"
  12 #include "base/message_loop/message_loop_proxy.h"
  13 #include "base/metrics/histogram.h"
  14 #include "base/task_runner.h"
  15 #include "base/threading/worker_pool.h"
  16 #include "net/base/io_buffer.h"
  17 #include "net/base/net_errors.h"
  18
  19 namespace net {
  20
  21 namespace {
  22
  23 void SetOffset(OVERLAPPED* overlapped, const LARGE_INTEGER& offset) {
  24   overlapped->Offset = offset.LowPart;
  25   overlapped->OffsetHigh = offset.HighPart;
  26 }
  27
  28 void IncrementOffset(OVERLAPPED* overlapped, DWORD count) {
  29   LARGE_INTEGER offset;
  30   offset.LowPart = overlapped->Offset;
  31   offset.HighPart = overlapped->OffsetHigh;
  32   offset.QuadPart += static_cast<LONGLONG>(count);
  33   SetOffset(overlapped, offset);
  34 }
  35
  36 }  // namespace
  37
  38 FileStream::Context::Context(const scoped_refptr<base::TaskRunner>& task_runner)
  39     : io_context_(),
  40       async_in_progress_(false),
  41       orphaned_(false),
  42       task_runner_(task_runner),
  43       async_read_initiated_(false),
  44       async_read_completed_(false),
  45       io_complete_for_read_received_(false),
  46       result_(0) {
  47   io_context_.handler = this;
  48   memset(&io_context_.overlapped, 0, sizeof(io_context_.overlapped));
  49 }
  50
  51 FileStream::Context::Context(base::File file,
  52                              const scoped_refptr<base::TaskRunner>& task_runner)
  53     : io_context_(),
  54       file_(file.Pass()),
  55       async_in_progress_(false),
  56       orphaned_(false),
  57       task_runner_(task_runner),
  58       async_read_initiated_(false),
  59       async_read_completed_(false),
  60       io_complete_for_read_received_(false),
  61       result_(0) {
  62   io_context_.handler = this;
  63   memset(&io_context_.overlapped, 0, sizeof(io_context_.overlapped));
  64   if (file_.IsValid()) {
  65     // TODO(hashimoto): Check that file_ is async.
  66     OnFileOpened();
  67   }
  68 }
  69
  70 FileStream::Context::~Context() {
  71 }
  72
  73 int FileStream::Context::Read(IOBuffer* buf,
  74                               int buf_len,
  75                               const CompletionCallback& callback) {
  76   CHECK(!async_in_progress_);
  77   DCHECK(!async_read_initiated_);
  78   DCHECK(!async_read_completed_);
  79   DCHECK(!io_complete_for_read_received_);
  80
  81   IOCompletionIsPending(callback, buf);
  82
  83   async_read_initiated_ = true;
  84   result_ = 0;
  85
  86   task_runner_->PostTask(
  87       FROM_HERE,
  88       base::Bind(&FileStream::Context::ReadAsync, base::Unretained(this),
  89                  file_.GetPlatformFile(), make_scoped_refptr(buf), buf_len,
  90                  &io_context_.overlapped,
  91                  base::MessageLoop::current()->message_loop_proxy()));
  92   return ERR_IO_PENDING;
  93 }
  94
  95 int FileStream::Context::Write(IOBuffer* buf,
  96                                int buf_len,
  97                                const CompletionCallback& callback) {
  98   CHECK(!async_in_progress_);
  99
 100   result_ = 0;
 101
 102   DWORD bytes_written = 0;
 103   if (!WriteFile(file_.GetPlatformFile(), buf->data(), buf_len,
 104                  &bytes_written, &io_context_.overlapped)) {
 105     IOResult error = IOResult::FromOSError(GetLastError());
 106     if (error.os_error == ERROR_IO_PENDING)
 107       IOCompletionIsPending(callback, buf);
 108     else
 109       LOG(WARNING) << "WriteFile failed: " << error.os_error;
 110     return static_cast<int>(error.result);
 111   }
 112
 113   IOCompletionIsPending(callback, buf);
 114   return ERR_IO_PENDING;
 115 }
 116
 117 FileStream::Context::IOResult FileStream::Context::SeekFileImpl(
 118     base::File::Whence whence,
 119     int64 offset) {
 120   LARGE_INTEGER result;
 121   result.QuadPart = file_.Seek(whence, offset);
 122   if (result.QuadPart >= 0) {
 123     SetOffset(&io_context_.overlapped, result);
 124     return IOResult(result.QuadPart, 0);
 125   }
 126
 127   return IOResult::FromOSError(GetLastError());
 128 }
 129
 130 void FileStream::Context::OnFileOpened() {
 131   base::MessageLoopForIO::current()->RegisterIOHandler(file_.GetPlatformFile(),
 132                                                        this);
 133 }
 134
 135 void FileStream::Context::IOCompletionIsPending(
 136     const CompletionCallback& callback,
 137     IOBuffer* buf) {
 138   DCHECK(callback_.is_null());
 139   callback_ = callback;
 140   in_flight_buf_ = buf;  // Hold until the async operation ends.
 141   async_in_progress_ = true;
 142 }
 143
 144 void FileStream::Context::OnIOCompleted(
 145     base::MessageLoopForIO::IOContext* context,
 146     DWORD bytes_read,
 147     DWORD error) {
 148   DCHECK_EQ(&io_context_, context);
 149   DCHECK(!callback_.is_null());
 150   DCHECK(async_in_progress_);
 151
 152   if (!async_read_initiated_)
 153     async_in_progress_ = false;
 154
 155   if (orphaned_) {
 156     io_complete_for_read_received_ = true;
 157     // If we are called due to a pending read and the asynchronous read task
 158     // has not completed we have to keep the context around until it completes.
 159     if (async_read_initiated_ && !async_read_completed_)
 160       return;
 161     DeleteOrphanedContext();
 162     return;
 163   }
 164
 165   if (error == ERROR_HANDLE_EOF) {
 166     result_ = 0;
 167   } else if (error) {
 168     IOResult error_result = IOResult::FromOSError(error);
 169     result_ = static_cast<int>(error_result.result);
 170   } else {
 171     if (result_)
 172       DCHECK_EQ(result_, static_cast<int>(bytes_read));
 173     result_ = bytes_read;
 174     IncrementOffset(&io_context_.overlapped, bytes_read);
 175   }
 176
 177   if (async_read_initiated_)
 178     io_complete_for_read_received_ = true;
 179
 180   InvokeUserCallback();
 181 }
 182
 183 void FileStream::Context::InvokeUserCallback() {
 184   // For an asynchonous Read operation don't invoke the user callback until
 185   // we receive the IO completion notification and the asynchronous Read
 186   // completion notification.
 187   if (async_read_initiated_) {
 188     if (!io_complete_for_read_received_ || !async_read_completed_)
 189       return;
 190     async_read_initiated_ = false;
 191     io_complete_for_read_received_ = false;
 192     async_read_completed_ = false;
 193     async_in_progress_ = false;
 194   }
 195   CompletionCallback temp_callback = callback_;
 196   callback_.Reset();
 197   scoped_refptr<IOBuffer> temp_buf = in_flight_buf_;
 198   in_flight_buf_ = NULL;
 199   temp_callback.Run(result_);
 200 }
 201
 202 void FileStream::Context::DeleteOrphanedContext() {
 203   async_in_progress_ = false;
 204   callback_.Reset();
 205   in_flight_buf_ = NULL;
 206   CloseAndDelete();
 207 }
 208
 209 // static
 210 void FileStream::Context::ReadAsync(
 211     FileStream::Context* context,
 212     HANDLE file,
 213     scoped_refptr<IOBuffer> buf,
 214     int buf_len,
 215     OVERLAPPED* overlapped,
 216     scoped_refptr<base::MessageLoopProxy> origin_thread_loop) {
 217   DWORD bytes_read = 0;
 218   BOOL ret = ::ReadFile(file, buf->data(), buf_len, &bytes_read, overlapped);
 219   origin_thread_loop->PostTask(
 220       FROM_HERE,
 221       base::Bind(&FileStream::Context::ReadAsyncResult,
 222                  base::Unretained(context), ret, bytes_read, ::GetLastError()));
 223 }
 224
 225 void FileStream::Context::ReadAsyncResult(BOOL read_file_ret,
 226                                           DWORD bytes_read,
 227                                           DWORD os_error) {
 228   // If the context is orphaned and we already received the io completion
 229   // notification then we should delete the context and get out.
 230   if (orphaned_ && io_complete_for_read_received_) {
 231     DeleteOrphanedContext();
 232     return;
 233   }
 234
 235   async_read_completed_ = true;
 236   if (read_file_ret) {
 237     result_ = bytes_read;
 238     InvokeUserCallback();
 239     return;
 240   }
 241
 242   IOResult error = IOResult::FromOSError(os_error);
 243   if (error.os_error == ERROR_IO_PENDING) {
 244     InvokeUserCallback();
 245   } else {
 246     OnIOCompleted(&io_context_, 0, error.os_error);
 247   }
 248 }
 249
 250 }  // namespace net