third_party/WebKit/Source/platform/blob/BlobData.cpp

/*
 * Copyright (C) 2010 Google Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above
 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
 * distribution.
 *     * Neither the name of Google Inc. nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "platform/blob/BlobData.h"

#include "platform/UUID.h"
#include "platform/blob/BlobRegistry.h"
#include "platform/text/LineEnding.h"
#include "wtf/PassRefPtr.h"
#include "wtf/PtrUtil.h"
#include "wtf/RefPtr.h"
#include "wtf/Vector.h"
#include "wtf/text/CString.h"
#include "wtf/text/TextEncoding.h"
#include <memory>

namespace blink {

namespace {

// All consecutive items that are accumulate to < this number will have the
// data appended to the same item.
static const size_t kMaxConsolidatedItemSizeInBytes = 15 * 1024;

// http://dev.w3.org/2006/webapi/FileAPI/#constructorBlob
bool isValidBlobType(const String& type)
{
    for (unsigned i = 0; i < type.length(); ++i) {
        UChar c = type[i];
        if (c < 0x20 || c > 0x7E)
            return false;
    }
    return true;
}

} // namespace

const long long BlobDataItem::toEndOfFile = -1;

RawData::RawData()
{
}

void RawData::detachFromCurrentThread()
{
}

void BlobDataItem::detachFromCurrentThread()
{
    data->detachFromCurrentThread();
    path = path.isolatedCopy();
    fileSystemURL = fileSystemURL.copy();
}

std::unique_ptr<BlobData> BlobData::create()
{
    return wrapUnique(new BlobData());
}

void BlobData::detachFromCurrentThread()
{
    m_contentType = m_contentType.isolatedCopy();
    for (size_t i = 0; i < m_items.size(); ++i)
        m_items.at(i).detachFromCurrentThread();
}

void BlobData::setContentType(const String& contentType)
{
    if (isValidBlobType(contentType))
        m_contentType = contentType;
    else
        m_contentType = "";
}

void BlobData::appendData(PassRefPtr<RawData> data, long long offset, long long length)
{
    m_items.append(BlobDataItem(std::move(data), offset, length));
}

void BlobData::appendFile(const String& path)
{
    m_items.append(BlobDataItem(path));
}

void BlobData::appendFile(const String& path, long long offset, long long length, double expectedModificationTime)
{
    m_items.append(BlobDataItem(path, offset, length, expectedModificationTime));
}

void BlobData::appendBlob(PassRefPtr<BlobDataHandle> dataHandle, long long offset, long long length)
{
    m_items.append(BlobDataItem(std::move(dataHandle), offset, length));
}

void BlobData::appendFileSystemURL(const KURL& url, long long offset, long long length, double expectedModificationTime)
{
    m_items.append(BlobDataItem(url, offset, length, expectedModificationTime));
}

void BlobData::appendText(const String& text, bool doNormalizeLineEndingsToNative)
{
    CString utf8Text = UTF8Encoding().encode(text, WTF::EntitiesForUnencodables);
    RefPtr<RawData> data = nullptr;
    Vector<char>* buffer;
    if (canConsolidateData(text.length())) {
        buffer = m_items.last().data->mutableData();
    } else {
        data = RawData::create();
        buffer = data->mutableData();
    }

    if (doNormalizeLineEndingsToNative) {
        normalizeLineEndingsToNative(utf8Text, *buffer);
    } else {
        buffer->append(utf8Text.data(), utf8Text.length());
    }

    if (data)
        m_items.append(BlobDataItem(data.release()));
}

void BlobData::appendBytes(const void* bytes, size_t length)
{
    if (canConsolidateData(length)) {
        m_items.last().data->mutableData()->append(
            static_cast<const char*>(bytes),
            length);
        return;
    }
    RefPtr<RawData> data = RawData::create();
    Vector<char>* buffer = data->mutableData();
    buffer->append(static_cast<const char *>(bytes), length);
    m_items.append(BlobDataItem(data.release()));
}

long long BlobData::length() const
{
    long long length = 0;

    for (Vector<BlobDataItem>::const_iterator it = m_items.begin(); it != m_items.end(); ++it) {
        const BlobDataItem& item = *it;
        if (item.length != BlobDataItem::toEndOfFile) {
            ASSERT(item.length >= 0);
            length += item.length;
            continue;
        }

        switch (item.type) {
        case BlobDataItem::Data:
            length += item.data->length();
            break;
        case BlobDataItem::File:
        case BlobDataItem::Blob:
        case BlobDataItem::FileSystemURL:
            return BlobDataItem::toEndOfFile;
        }
    }
    return length;
}

bool BlobData::canConsolidateData(size_t length)
{
    if (m_items.isEmpty())
        return false;
    BlobDataItem& lastItem = m_items.last();
    if (lastItem.type != BlobDataItem::Data)
        return false;
    if (lastItem.data->length() + length > kMaxConsolidatedItemSizeInBytes)
        return false;
    return true;
}

BlobDataHandle::BlobDataHandle()
    : m_uuid(createCanonicalUUIDString())
    , m_size(0)
{
    BlobRegistry::registerBlobData(m_uuid, BlobData::create());
}

BlobDataHandle::BlobDataHandle(std::unique_ptr<BlobData> data, long long size)
    : m_uuid(createCanonicalUUIDString())
    , m_type(data->contentType().isolatedCopy())
    , m_size(size)
{
    BlobRegistry::registerBlobData(m_uuid, std::move(data));
}

BlobDataHandle::BlobDataHandle(const String& uuid, const String& type, long long size)
    : m_uuid(uuid.isolatedCopy())
    , m_type(isValidBlobType(type) ? type.isolatedCopy() : "")
    , m_size(size)
{
    BlobRegistry::addBlobDataRef(m_uuid);
}

BlobDataHandle::~BlobDataHandle()
{
    BlobRegistry::removeBlobDataRef(m_uuid);
}

} // namespace blink