blob: a8471eef1d19fe9d581038775a9bc76eac46bf07 [file] [log] [blame]
// Copyright 2018 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 "chrome/browser/download/image_thumbnail_request.h"
#include <memory>
#include "base/files/file_util.h"
#include "base/task/post_task.h"
#include "base/threading/scoped_blocking_call.h"
#include "content/public/browser/browser_thread.h"
#include "skia/ext/image_operations.h"
namespace {
// Ignore image files that are too large to avoid long delays.
const int64_t kMaxImageSize = 10 * 1024 * 1024; // 10 MB
std::string LoadImageData(const base::FilePath& path) {
base::ScopedBlockingCall scoped_blocking_call(base::BlockingType::WILL_BLOCK);
// Confirm that the file's size is within our threshold.
int64_t file_size;
if (!base::GetFileSize(path, &file_size) || file_size > kMaxImageSize) {
LOG(ERROR) << "Unexpected file size: " << path.MaybeAsASCII() << ", "
<< file_size;
return std::string();
}
std::string data;
bool success = base::ReadFileToString(path, &data);
// Make sure the file isn't empty.
if (!success || data.empty()) {
LOG(ERROR) << "Failed to read file: " << path.MaybeAsASCII();
return std::string();
}
return data;
}
SkBitmap ScaleDownBitmap(int icon_size, const SkBitmap& decoded_image) {
DCHECK(!content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
if (decoded_image.drawsNothing())
return decoded_image;
// Shrink the image down so that its smallest dimension is equal to or
// smaller than the requested size.
int min_dimension = std::min(decoded_image.width(), decoded_image.height());
if (min_dimension <= icon_size)
return decoded_image;
uint64_t width = static_cast<uint64_t>(decoded_image.width());
uint64_t height = static_cast<uint64_t>(decoded_image.height());
return skia::ImageOperations::Resize(
decoded_image, skia::ImageOperations::RESIZE_BEST,
width * icon_size / min_dimension, height * icon_size / min_dimension);
}
} // namespace
ImageThumbnailRequest::ImageThumbnailRequest(
int icon_size,
base::OnceCallback<void(const SkBitmap&)> callback)
: icon_size_(icon_size),
callback_(std::move(callback)),
weak_ptr_factory_(this) {
DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
}
ImageThumbnailRequest::~ImageThumbnailRequest() {
DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
}
void ImageThumbnailRequest::Start(const base::FilePath& path) {
DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
base::PostTaskWithTraitsAndReplyWithResult(
FROM_HERE, {base::MayBlock(), base::TaskPriority::USER_BLOCKING},
base::BindOnce(&LoadImageData, path),
base::BindOnce(&ImageThumbnailRequest::OnLoadComplete,
weak_ptr_factory_.GetWeakPtr()));
}
void ImageThumbnailRequest::OnImageDecoded(const SkBitmap& decoded_image) {
DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
base::PostTaskWithTraitsAndReplyWithResult(
FROM_HERE, {base::MayBlock(), base::TaskPriority::USER_BLOCKING},
base::BindOnce(&ScaleDownBitmap, icon_size_, decoded_image),
base::BindOnce(&ImageThumbnailRequest::FinishRequest,
weak_ptr_factory_.GetWeakPtr()));
}
void ImageThumbnailRequest::OnDecodeImageFailed() {
DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
LOG(ERROR) << "Failed to decode image.";
FinishRequest(SkBitmap());
}
void ImageThumbnailRequest::OnLoadComplete(const std::string& data) {
DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
if (data.empty()) {
FinishRequest(SkBitmap());
return;
}
ImageDecoder::Start(this, data);
}
void ImageThumbnailRequest::FinishRequest(const SkBitmap& thumbnail) {
DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
content::BrowserThread::PostTask(
content::BrowserThread::UI, FROM_HERE,
base::BindOnce(std::move(callback_), thumbnail));
delete this;
}