Adds imageWriterPrivate support for Windows

chrome/utility/image_writer/image_writer.cc

+// Copyright 2013 The Chromium Authors. All rights reserved.
+// Use of this image code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "base/platform_file.h"
+#include "chrome/utility/image_writer/error_messages.h"
+#include "chrome/utility/image_writer/image_writer.h"
+#include "chrome/utility/image_writer/image_writer_handler.h"
+#include "content/public/utility/utility_thread.h"
+
+namespace chrome {
+namespace image_writer {
+
+// Since block devices like large sequential access and IPC is expensive we're
+// doing work in 1MB chunks.
+const int kBurningBlockSize = 1 << 20;
+
+ImageWriter::ImageWriter(ImageWriterHandler* handler)
+    : image_file_(base::kInvalidPlatformFileValue),
+      device_file_(base::kInvalidPlatformFileValue),
+      bytes_processed_(0),
+      handler_(handler) {}
+
+ImageWriter::~ImageWriter() { CleanUp(); }
+
+void ImageWriter::Write(const base::FilePath& image_path,
+                        const base::FilePath& device_path) {
+  if (IsRunning()) {
+    handler_->SendFailed(error::kOperationAlreadyInProgress);
+    return;
+  }
+
+  image_path_ = image_path;
+  device_path_ = device_path;
+  bytes_processed_ = 0;
+
+  base::PlatformFileError error;
+
+  image_file_ = base::CreatePlatformFile(
+      image_path_,
+      base::PLATFORM_FILE_OPEN | base::PLATFORM_FILE_READ,
+      NULL,
+      &error);
+
+  if (error != base::PLATFORM_FILE_OK) {
+    DLOG(ERROR) << "Unable to open file for read: " << image_path_.value();
+    Error(error::kOpenImage);
+    return;
+  }
+
+#if defined(OS_WIN)
+  // Windows requires that device files be opened with FILE_FLAG_NO_BUFFERING
+  // and FILE_FLAG_WRITE_THROUGH.  These two flags are not part of
+  // PlatformFile::CreatePlatformFile.
+  device_file_ = CreateFile(device_path.value().c_str(),
+                            GENERIC_WRITE,
+                            FILE_SHARE_WRITE,
+                            NULL,
+                            OPEN_EXISTING,
+                            FILE_FLAG_NO_BUFFERING | FILE_FLAG_WRITE_THROUGH,
+                            INVALID_HANDLE_VALUE);
+
+  if (device_file_ == base::kInvalidPlatformFileValue) {
+    Error(error::kOpenDevice);
+    return;
+  }
+#else
+  device_file_ = base::CreatePlatformFile(
+      device_path_,
+      base::PLATFORM_FILE_OPEN | base::PLATFORM_FILE_WRITE,
+      NULL,
+      &error);
+
+  if (error != base::PLATFORM_FILE_OK) {
+    DLOG(ERROR) << "Unable to open file for write(" << error
+                << "): " << device_path_.value();
+    Error(error::kOpenDevice);
+    return;
+  }
+#endif
+
+  PostProgress(0);
+
+  PostTask(base::Bind(&ImageWriter::WriteChunk, AsWeakPtr()));
+}
+
+void ImageWriter::Verify(const base::FilePath& image_path,
+                         const base::FilePath& device_path) {
+  if (IsRunning()) {
+    handler_->SendFailed(error::kOperationAlreadyInProgress);
+    return;
+  }
+
+  image_path_ = image_path;
+  device_path_ = device_path;
+  bytes_processed_ = 0;
+
+  base::PlatformFileError error;
+
+  image_file_ = base::CreatePlatformFile(
+      image_path_,
+      base::PLATFORM_FILE_OPEN | base::PLATFORM_FILE_READ,
+      NULL,
+      &error);
+
+  if (error != base::PLATFORM_FILE_OK) {
+    DLOG(ERROR) << "Unable to open file for read: " << image_path_.value();
+    Error(error::kOpenImage);
+    return;
+  }
+
+  device_file_ = base::CreatePlatformFile(
+      device_path_,
+      base::PLATFORM_FILE_OPEN | base::PLATFORM_FILE_READ,
+      NULL,
+      &error);
+
+  if (error != base::PLATFORM_FILE_OK) {
+    DLOG(ERROR) << "Unable to open file for read: " << device_path_.value();
+    Error(error::kOpenDevice);
+    return;
+  }
+
+  PostProgress(0);
+
+  PostTask(base::Bind(&ImageWriter::VerifyChunk, AsWeakPtr()));
+}
+
+void ImageWriter::Cancel() {
+  CleanUp();
+  handler_->SendCancelled();
+}
+
+bool ImageWriter::IsRunning() {

[Lei Zhang, 2014/02/15 00:49:16]

nit: const method

[Drew Haven, 2014/02/15 01:23:58]

Done.

+  return image_file_ != base::kInvalidPlatformFileValue ||
+         device_file_ != base::kInvalidPlatformFileValue;
+}
+
+void ImageWriter::PostTask(const base::Closure& task) {
+  base::MessageLoop::current()->PostTask(FROM_HERE, task);
+}
+
+void ImageWriter::PostProgress(int64 progress) {
+  handler_->SendProgress(progress);
+}
+
+void ImageWriter::Error(const std::string& message) {
+  CleanUp();
+  handler_->SendFailed(message);
+}
+
+void ImageWriter::WriteChunk() {
+  if (!IsRunning()) {
+    return;
+  }
+
+  scoped_ptr<char[]> buffer(new char[kBurningBlockSize]);
+  base::PlatformFileInfo info;
+
+  int bytes_read = base::ReadPlatformFile(
+      image_file_, bytes_processed_, buffer.get(), kBurningBlockSize);
+
+  if (bytes_read > 0) {
+    // Always attempt to write a whole block, as Windows requires 512-byte
+    // aligned writes to devices.
+    int bytes_written = base::WritePlatformFile(
+        device_file_, bytes_processed_, buffer.get(), kBurningBlockSize);
+
+    if (bytes_written < bytes_read) {
+      Error(error::kWriteImage);
+      return;
+    }
+
+    bytes_processed_ += bytes_read;

[Lei Zhang, 2014/02/15 00:49:16]

Presumably it's ok to share |bytes_processed_| between Write and Verify because
only 1 operation can take place at any time?

[Drew Haven, 2014/02/15 01:23:58]

Correct. Since the PlatformFiles are ultimately the arbitrators this just shares
the same access restrictions.

+    PostProgress(bytes_processed_);
+
+    PostTask(base::Bind(&ImageWriter::WriteChunk, AsWeakPtr()));
+  } else if (bytes_read == 0) {
+    // End of file.
+    base::FlushPlatformFile(device_file_);
+    CleanUp();
+    handler_->SendSucceeded();
+  } else {
+    // Unable to read entire file.
+    Error(error::kReadImage);
+  }
+}
+
+void ImageWriter::VerifyChunk() {
+  if (!IsRunning()) {
+    return;
+  }
+
+  scoped_ptr<char[]> image_buffer(new char[kBurningBlockSize]);
+  scoped_ptr<char[]> device_buffer(new char[kBurningBlockSize]);
+  base::PlatformFileInfo info;
+  int image_size;
+
+  if (base::GetPlatformFileInfo(image_file_, &info)) {
+    image_size = info.size;
+  } else {
+    Error(error::kReadImage);

[Lei Zhang, 2014/02/15 00:49:16]

do you want to return in this case?

[Drew Haven, 2014/02/15 01:23:58]

Actually, I'm going to remove this because I should be able to count on
ReadPlatformFile returning 0 at the end of the file only for a regular file,
right?

+  }
+
+  int bytes_read = base::ReadPlatformFile(
+      image_file_, bytes_processed_, image_buffer.get(), kBurningBlockSize);
+
+  if (bytes_read > 0) {
+    if (base::ReadPlatformFile(device_file_,
+                               bytes_processed_,
+                               device_buffer.get(),
+                               kBurningBlockSize) < 0) {
+      LOG(ERROR) << "Failed to read " << kBurningBlockSize << " bytes of "
+                 << "device at offset " << bytes_processed_;
+      Error(error::kReadDevice);
+      return;
+    }
+
+    if (memcmp(image_buffer.get(), device_buffer.get(), bytes_read) != 0) {
+      LOG(ERROR) << "Write verification failed when comparing " << bytes_read
+                 << " bytes at " << bytes_processed_;
+      Error(error::kVerificationFailed);
+      return;
+    }
+
+    bytes_processed_ += bytes_read;
+    PostProgress(bytes_processed_);
+
+    PostTask(base::Bind(&ImageWriter::VerifyChunk, AsWeakPtr()));
+  } else if (bytes_read == 0 && bytes_processed_ == image_size) {
+    // End of file.
+    CleanUp();
+    handler_->SendSucceeded();
+  } else {
+    // Unable to read entire file.
+    LOG(ERROR) << "Failed to read " << kBurningBlockSize << " bytes of image "
+               << "at offset " << bytes_processed_;
+    Error(error::kReadImage);
+  }
+}
+
+void ImageWriter::CleanUp() {
+  if (image_file_ != base::kInvalidPlatformFileValue) {
+    base::ClosePlatformFile(image_file_);
+    image_file_ = base::kInvalidPlatformFileValue;
+  }
+  if (device_file_ != base::kInvalidPlatformFileValue) {
+    base::ClosePlatformFile(device_file_);
+    device_file_ = base::kInvalidPlatformFileValue;
+  }
+}
+
+}  // namespace image_writer
+}  // namespace chrome