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
  85   task_runner_->PostTask(
  86       FROM_HERE,
  87       base::Bind(&FileStream::Context::ReadAsync, base::Unretained(this),
  88                  file_.GetPlatformFile(), make_scoped_refptr(buf), buf_len,
  89                  &io_context_.overlapped,
  90                  base::MessageLoop::current()->message_loop_proxy()));
  91   return ERR_IO_PENDING;
  92 }
  93
  94 int FileStream::Context::Write(IOBuffer* buf,
  95                                int buf_len,
  96                                const CompletionCallback& callback) {
  97   CHECK(!async_in_progress_);
  98
  99   DWORD bytes_written = 0;
 100   if (!WriteFile(file_.GetPlatformFile(), buf->data(), buf_len,
 101                  &bytes_written, &io_context_.overlapped)) {
 102     IOResult error = IOResult::FromOSError(GetLastError());
 103     if (error.os_error == ERROR_IO_PENDING)
 104       IOCompletionIsPending(callback, buf);
 105     else
 106       LOG(WARNING) << "WriteFile failed: " << error.os_error;
 107     return static_cast<int>(error.result);
 108   }
 109
 110   IOCompletionIsPending(callback, buf);
 111   return ERR_IO_PENDING;
 112 }
 113
 114 FileStream::Context::IOResult FileStream::Context::SeekFileImpl(
 115     base::File::Whence whence,
 116     int64 offset) {
 117   LARGE_INTEGER result;
 118   result.QuadPart = file_.Seek(whence, offset);
 119   if (result.QuadPart >= 0) {
 120     SetOffset(&io_context_.overlapped, result);
 121     return IOResult(result.QuadPart, 0);
 122   }
 123
 124   return IOResult::FromOSError(GetLastError());
 125 }
 126
 127 void FileStream::Context::OnFileOpened() {
 128   base::MessageLoopForIO::current()->RegisterIOHandler(file_.GetPlatformFile(),
 129                                                        this);
 130 }
 131
 132 void FileStream::Context::IOCompletionIsPending(
 133     const CompletionCallback& callback,
 134     IOBuffer* buf) {
 135   DCHECK(callback_.is_null());
 136   callback_ = callback;
 137   in_flight_buf_ = buf;  // Hold until the async operation ends.
 138   async_in_progress_ = true;
 139 }
 140
 141 void FileStream::Context::OnIOCompleted(
 142     base::MessageLoopForIO::IOContext* context,
 143     DWORD bytes_read,
 144     DWORD error) {
 145   DCHECK_EQ(&io_context_, context);
 146   DCHECK(!callback_.is_null());
 147   DCHECK(async_in_progress_);
 148
 149   if (!async_read_initiated_)
 150     async_in_progress_ = false;
 151
 152   if (orphaned_) {
 153     async_in_progress_ = false;
 154     callback_.Reset();
 155     in_flight_buf_ = NULL;
 156     CloseAndDelete();
 157     return;
 158   }
 159
 160   if (error == ERROR_HANDLE_EOF) {
 161     result_ = 0;
 162   } else if (error) {
 163     IOResult error_result = IOResult::FromOSError(error);
 164     result_ = static_cast<int>(error_result.result);
 165   } else {
 166     result_ = bytes_read;
 167     IncrementOffset(&io_context_.overlapped, bytes_read);
 168   }
 169
 170   if (async_read_initiated_)
 171     io_complete_for_read_received_ = true;
 172
 173   InvokeUserCallback();
 174 }
 175
 176 void FileStream::Context::InvokeUserCallback() {
 177   // For an asynchonous Read operation don't invoke the user callback until
 178   // we receive the IO completion notification and the asynchronous Read
 179   // completion notification.
 180   if (async_read_initiated_) {
 181     if (!io_complete_for_read_received_ || !async_read_completed_)
 182       return;
 183     async_read_initiated_ = false;
 184     io_complete_for_read_received_ = false;
 185     async_read_completed_ = false;
 186     async_in_progress_ = false;
 187   }
 188   CompletionCallback temp_callback = callback_;
 189   callback_.Reset();
 190   scoped_refptr<IOBuffer> temp_buf = in_flight_buf_;
 191   in_flight_buf_ = NULL;
 192   temp_callback.Run(result_);
 193 }
 194
 195 // static
 196 void FileStream::Context::ReadAsync(
 197     FileStream::Context* context,
 198     HANDLE file,
 199     scoped_refptr<net::IOBuffer> buf,
 200     int buf_len,
 201     OVERLAPPED* overlapped,
 202     scoped_refptr<base::MessageLoopProxy> origin_thread_loop) {
 203   DWORD bytes_read = 0;
 204   BOOL ret = ::ReadFile(file, buf->data(), buf_len, &bytes_read, overlapped);
 205   origin_thread_loop->PostTask(
 206       FROM_HERE, base::Bind(&FileStream::Context::ReadAsyncResult,
 207                             base::Unretained(context), ret ? bytes_read : 0,
 208                             ret ? 0 : ::GetLastError()));
 209 }
 210
 211 void FileStream::Context::ReadAsyncResult(DWORD bytes_read, DWORD os_error) {
 212   if (!os_error)
 213     result_ = bytes_read;
 214
 215   IOResult error = IOResult::FromOSError(os_error);
 216   if (error.os_error == ERROR_HANDLE_EOF) {
 217     // Report EOF by returning 0 bytes read.
 218     OnIOCompleted(&io_context_, 0, error.os_error);
 219   } else if (error.os_error != ERROR_IO_PENDING) {
 220     // We don't need to inform the caller about ERROR_PENDING_IO as that was
 221     // already done when the ReadFile call was queued to the worker pool.
 222     if (error.os_error) {
 223       LOG(WARNING) << "ReadFile failed: " << error.os_error;
 224       OnIOCompleted(&io_context_, 0, error.os_error);
 225     }
 226   }
 227   async_read_completed_ = true;
 228   InvokeUserCallback();
 229 }
 230
 231 }  // namespace net