Revert of Significantly cleans up the ImageWriter Operation class and subclasses.

chrome/browser/extensions/api/image_writer_private/image_writer_utils.cc

+// Copyright 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "base/logging.h"
+#include "chrome/browser/extensions/api/image_writer_private/image_writer_utils.h"
+
+namespace extensions {
+namespace image_writer_utils
+{
+
+const int kFsyncRatio = 1024;
+
+ImageWriter::ImageWriter() : file_(base::kInvalidPlatformFileValue),
+                             writes_count_(0) {
+}
+
+ImageWriter::~ImageWriter() {
+  if (file_ != base::kInvalidPlatformFileValue)
+    base::ClosePlatformFile(file_);
+}
+
+bool ImageWriter::Open(const base::FilePath& path) {
+  if (file_ != base::kInvalidPlatformFileValue)
+    Close();
+  DCHECK_EQ(base::kInvalidPlatformFileValue, file_);
+  base::PlatformFileError error;
+  file_ = base::CreatePlatformFile(
+    path,
+    base::PLATFORM_FILE_OPEN | base::PLATFORM_FILE_WRITE,
+    NULL,
+    &error);
+  if (error != base::PLATFORM_FILE_OK) {
+    LOG(ERROR) << "Couldn't open target path "
+               << path.value() << ": " << error;
+    return false;
+  }
+  return true;
+}
+
+bool ImageWriter::Close() {
+  if (file_ != base::kInvalidPlatformFileValue &&
+      base::ClosePlatformFile(file_)) {
+    file_ = base::kInvalidPlatformFileValue;
+    return true;
+  } else {
+    LOG(ERROR) << "Could not close target file";
+    return false;
+  }
+}
+
+int ImageWriter::Write(const char* data_block, int data_size) {
+  int written = base::WritePlatformFileAtCurrentPos(file_, data_block,
+                                                    data_size);
+  if (written != data_size) {
+    LOG(ERROR) << "Error writing to target file";
+    return -1;
+  }
+
+  writes_count_++;
+  if (writes_count_ == kFsyncRatio) {
+    if (!base::FlushPlatformFile(file_)) {
+      LOG(ERROR) << "Error syncing target file";
+      return -1;
+    }
+    writes_count_ = 0;
+  }
+
+  return written;
+}
+
+ImageReader::ImageReader() : file_(base::kInvalidPlatformFileValue) {
+}
+
+ImageReader::~ImageReader() {
+  if (file_ != base::kInvalidPlatformFileValue)
+    base::ClosePlatformFile(file_);
+}
+
+bool ImageReader::Open(const base::FilePath& path) {
+  if (file_ != base::kInvalidPlatformFileValue)
+    Close();
+  DCHECK_EQ(base::kInvalidPlatformFileValue, file_);
+  base::PlatformFileError error;
+  file_ = base::CreatePlatformFile(
+    path,
+    base::PLATFORM_FILE_OPEN | base::PLATFORM_FILE_READ,
+    NULL,
+    &error);
+  if (error != base::PLATFORM_FILE_OK) {
+    LOG(ERROR) << "Couldn't open target path "
+               << path.value() << ": " << error;
+    return false;
+  }
+  return true;
+}
+
+bool ImageReader::Close() {
+  if (file_ != base::kInvalidPlatformFileValue &&
+      base::ClosePlatformFile(file_)) {
+    file_ = base::kInvalidPlatformFileValue;
+    return true;
+  } else {
+    LOG(ERROR) << "Could not close target file";
+    return false;
+  }
+  return true;
+}
+
+int ImageReader::Read(char* data_block, int data_size) {
+  int read = base::ReadPlatformFileAtCurrentPos(file_, data_block, data_size);
+  if (read < 0)
+    LOG(ERROR) << "Error reading from source file";
+  return read;
+}
+
+int64 ImageReader::GetSize() {
+  base::PlatformFileInfo info;
+  if (base::GetPlatformFileInfo(file_, &info)) {
+    return info.size;
+  } else {
+    return 0;
+  }
+}
+
+} // namespace image_writer_utils
+} // namespace extensions