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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
// Qt-Security score:critical reason:data-parser
#include "qtgafile.h"
#include <QtCore/QIODevice>
#include <QtCore/QDebug>
#include <QtCore/QDateTime>
#include <QtGui/QImageIOHandler>
namespace {
struct TgaReader
{
Q_DISABLE_COPY(TgaReader)
TgaReader() = default;
virtual ~TgaReader() {}
virtual QRgb operator()(QIODevice *s) const = 0;
};
struct Tga16Reader : public TgaReader
{
~Tga16Reader() {}
QRgb operator()(QIODevice *s) const override
{
char ch1, ch2;
if (s->getChar(&ch1) && s->getChar(&ch2)) {
quint16 d = (int(ch1) & 0xFF) | ((int(ch2) & 0xFF) << 8);
QRgb result = (d & 0x8000) ? 0xFF000000 : 0x00000000;
result |= ((d & 0x7C00) << 6) | ((d & 0x03E0) << 3) | (d & 0x001F);
return result;
} else {
return 0;
}
}
};
struct Tga24Reader : public TgaReader
{
QRgb operator()(QIODevice *s) const override
{
char r, g, b;
if (s->getChar(&b) && s->getChar(&g) && s->getChar(&r))
return qRgb(uchar(r), uchar(g), uchar(b));
else
return 0;
}
};
struct Tga32Reader : public TgaReader
{
QRgb operator()(QIODevice *s) const override
{
char r, g, b, a;
if (s->getChar(&b) && s->getChar(&g) && s->getChar(&r) && s->getChar(&a))
return qRgba(uchar(r), uchar(g), uchar(b), uchar(a));
else
return 0;
}
};
} // namespace
/*!
\class QTgaFile
\since 4.8
\internal
File data container for a TrueVision Graphics format file.
Format is as described here:
Usage is:
\code
QTgaFile tga(myFile);
QImage tgaImage;
if (tga.isValid())
tgaImage = tga.readImage();
\endcode
The class is designed to handle sequential and non-sequential
sources, so during construction the mHeader is read. Then during
the readImage() call the rest of the data is read.
After passing myFile to the constructor, if the QIODevice *myFile
is read, or has seek() called, the results are undefined - so don't
do that.
*/
/*!
Construct a new QTgaFile object getting data from \a device.
The object does not take ownership of the \a device, but until the
object is destroyed do not do any non-const operations, eg seek or
read on the device.
*/
QTgaFile::QTgaFile(QIODevice *device)
: mDevice(device)
{
::memset(mHeader, 0, HeaderSize);
if (!mDevice->isReadable())
{
mErrorMessage = tr("Could not read image data");
return;
}
if (mDevice->isSequential())
{
mErrorMessage = tr("Sequential device (eg socket) for image read not supported");
return;
}
if (!mDevice->seek(0))
{
mErrorMessage = tr("Seek file/device for image read failed");
return;
}
if (device->read(reinterpret_cast<char*>(mHeader), HeaderSize) != HeaderSize) {
mErrorMessage = tr("Image header read failed");
return;
}
if (mHeader[ImageType] != 2)
{
// TODO: should support other image types
mErrorMessage = tr("Image type not supported");
return;
}
int bitsPerPixel = mHeader[PixelDepth];
bool validDepth = (bitsPerPixel == 16 || bitsPerPixel == 24 || bitsPerPixel == 32);
if (!validDepth)
{
mErrorMessage = tr("Image depth not valid");
return;
}
if (quint64(width()) * quint64(height()) > (8192 * 8192))
{
mErrorMessage = tr("Image size exceeds limit");
return;
}
}
/*!
\internal
Destroy the device, recovering any resources.
*/
QTgaFile::~QTgaFile()
{
}
/*!
\internal
Reads an image file from the QTgaFile's device, and returns it.
This method seeks to the absolute position of the image data in the file,
so no assumptions are made about where the devices read pointer is when this
method is called. For this reason only random access devices are supported.
If the constructor completed successfully, such that isValid() returns true,
then this method is likely to succeed, unless the file is somehow corrupted.
In the case that the read fails, the QImage returned will be null, such that
QImage::isNull() will be true.
*/
QImage QTgaFile::readImage()
{
if (!isValid())
return QImage();
int offset = mHeader[IdLength]; // Mostly always zero
// Even in TrueColor files a color palette may be present so we have to check it here
// even we only support image type 2 (= uncompressed true-color image)
if (mHeader[ColorMapType] == 1) {
int cmapDepth = mHeader[CMapDepth];
if (cmapDepth == 15) // 15 bit is stored as 16 bit + ignoring the highest bit (no alpha)
cmapDepth = 16;
if (cmapDepth != 16 && cmapDepth != 24 && cmapDepth != 32) {
mErrorMessage = tr("Invalid color map depth (%1)").arg(cmapDepth);
return {};
}
offset += littleEndianInt(&mHeader[CMapLength]) * cmapDepth / 8;
}
mDevice->seek(HeaderSize + offset);
int bitsPerPixel = mHeader[PixelDepth];
int imageWidth = width();
int imageHeight = height();
unsigned char desc = mHeader[ImageDescriptor];
//unsigned char xCorner = desc & 0x10; // 0 = left, 1 = right
unsigned char yCorner = desc & 0x20; // 0 = lower, 1 = upper
const qint64 pixelDataSize = qint64(imageWidth) * imageHeight * (bitsPerPixel / 8);
if (mDevice->size() > 0 && mDevice->size() - mDevice->pos() < pixelDataSize) {
mErrorMessage = tr("Insufficient image data for declared image size");
return {};
}
QImage im;
if (!QImageIOHandler::allocateImage(QSize(imageWidth, imageHeight), QImage::Format_ARGB32, &im))
return QImage();
TgaReader *reader = 0;
if (bitsPerPixel == 16)
reader = new Tga16Reader();
else if (bitsPerPixel == 24)
reader = new Tga24Reader();
else if (bitsPerPixel == 32)
reader = new Tga32Reader();
else
return QImage();
TgaReader &read = *reader;
// For now only deal with yCorner, since no one uses xCorner == 1
// Also this is upside down, since Qt has the origin flipped
if (yCorner)
{
for (int y = 0; y < imageHeight; ++y)
for (int x = 0; x < imageWidth; ++x)
im.setPixel(x, y, read(mDevice));
}
else
{
for (int y = imageHeight - 1; y >= 0; --y)
for (int x = 0; x < imageWidth; ++x)
im.setPixel(x, y, read(mDevice));
}
delete reader;
// TODO: add processing of TGA extension information - ie TGA 2.0 files
return im;
}