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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:significant reason:default
#include "qlinuxfbscreen.h"
#include <QtFbSupport/private/qfbcursor_p.h>
#include <QtFbSupport/private/qfbwindow_p.h>
#include <QtCore/QFile>
#include <QtCore/QRegularExpression>
#include <QtCore/q20utility.h>
#include <QtGui/QPainter>
#include <private/qcore_unix_p.h> // overrides QT_OPEN
#include <qimage.h>
#include <qdebug.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <linux/kd.h>
#include <fcntl.h>
#include <errno.h>
#include <stdio.h>
#include <limits.h>
#include <signal.h>
#include <linux/fb.h>
QT_BEGIN_NAMESPACE
using namespace Qt::StringLiterals;
static int openFramebufferDevice(const QString &dev)
{
int fd = -1;
if (access(dev.toLatin1().constData(), R_OK|W_OK) == 0)
fd = QT_OPEN(dev.toLatin1().constData(), O_RDWR);
if (fd == -1) {
if (access(dev.toLatin1().constData(), R_OK) == 0)
fd = QT_OPEN(dev.toLatin1().constData(), O_RDONLY);
}
return fd;
}
static int determineDepth(const fb_var_screeninfo &vinfo)
{
int depth = vinfo.bits_per_pixel;
if (depth== 24) {
depth = vinfo.red.length + vinfo.green.length + vinfo.blue.length;
if (depth <= 0)
depth = 24; // reset if color component lengths are not reported
} else if (depth == 16) {
depth = vinfo.red.length + vinfo.green.length + vinfo.blue.length;
if (depth <= 0)
depth = 16;
}
return depth;
}
static QRect determineGeometry(const fb_var_screeninfo &vinfo, const QRect &userGeometry)
{
int xoff = vinfo.xoffset;
int yoff = vinfo.yoffset;
int w, h;
if (userGeometry.isValid()) {
w = userGeometry.width();
h = userGeometry.height();
if (q20::cmp_greater(w, vinfo.xres))
w = vinfo.xres;
if (q20::cmp_greater(h, vinfo.yres))
h = vinfo.yres;
int xxoff = userGeometry.x(), yyoff = userGeometry.y();
if (xxoff != 0 || yyoff != 0) {
if (xxoff < 0 || q20::cmp_greater(xxoff + w, vinfo.xres))
xxoff = vinfo.xres - w;
if (yyoff < 0 || q20::cmp_greater(yyoff + h, vinfo.yres))
yyoff = vinfo.yres - h;
xoff += xxoff;
yoff += yyoff;
} else {
xoff += (vinfo.xres - w)/2;
yoff += (vinfo.yres - h)/2;
}
} else {
w = vinfo.xres;
h = vinfo.yres;
}
if (w == 0 || h == 0) {
qWarning("Unable to find screen geometry, using 320x240");
w = 320;
h = 240;
}
return QRect(xoff, yoff, w, h);
}
static QSizeF determinePhysicalSize(const fb_var_screeninfo &vinfo, const QSize &mmSize, const QSize &res)
{
int mmWidth = mmSize.width(), mmHeight = mmSize.height();
if (mmWidth <= 0 && mmHeight <= 0) {
if (vinfo.width != 0 && vinfo.height != 0
&& vinfo.width != UINT_MAX && vinfo.height != UINT_MAX) {
mmWidth = vinfo.width;
mmHeight = vinfo.height;
} else {
const int dpi = 100;
mmWidth = qRound(res.width() * 25.4 / dpi);
mmHeight = qRound(res.height() * 25.4 / dpi);
}
} else if (mmWidth > 0 && mmHeight <= 0) {
mmHeight = res.height() * mmWidth/res.width();
} else if (mmHeight > 0 && mmWidth <= 0) {
mmWidth = res.width() * mmHeight/res.height();
}
return QSize(mmWidth, mmHeight);
}
static QImage::Format determineFormat(const fb_var_screeninfo &info, int depth)
{
const fb_bitfield rgba[4] = { info.red, info.green,
info.blue, info.transp };
QImage::Format format = QImage::Format_Invalid;
switch (depth) {
case 32: {
const fb_bitfield argb8888[4] = {{16, 8, 0}, {8, 8, 0},
{0, 8, 0}, {24, 8, 0}};
const fb_bitfield abgr8888[4] = {{0, 8, 0}, {8, 8, 0},
{16, 8, 0}, {24, 8, 0}};
if (memcmp(rgba, argb8888, 4 * sizeof(fb_bitfield)) == 0) {
format = QImage::Format_ARGB32;
} else if (memcmp(rgba, argb8888, 3 * sizeof(fb_bitfield)) == 0) {
format = QImage::Format_RGB32;
} else if (memcmp(rgba, abgr8888, 3 * sizeof(fb_bitfield)) == 0) {
format = QImage::Format_RGB32;
// pixeltype = BGRPixel;
}
break;
}
case 24: {
const fb_bitfield rgb888[4] = {{16, 8, 0}, {8, 8, 0},
{0, 8, 0}, {0, 0, 0}};
const fb_bitfield bgr888[4] = {{0, 8, 0}, {8, 8, 0},
{16, 8, 0}, {0, 0, 0}};
if (memcmp(rgba, rgb888, 3 * sizeof(fb_bitfield)) == 0) {
format = QImage::Format_RGB888;
} else if (memcmp(rgba, bgr888, 3 * sizeof(fb_bitfield)) == 0) {
format = QImage::Format_BGR888;
// pixeltype = BGRPixel;
}
break;
}
case 18: {
const fb_bitfield rgb666[4] = {{12, 6, 0}, {6, 6, 0},
{0, 6, 0}, {0, 0, 0}};
if (memcmp(rgba, rgb666, 3 * sizeof(fb_bitfield)) == 0)
format = QImage::Format_RGB666;
break;
}
case 16: {
const fb_bitfield rgb565[4] = {{11, 5, 0}, {5, 6, 0},
{0, 5, 0}, {0, 0, 0}};
const fb_bitfield bgr565[4] = {{0, 5, 0}, {5, 6, 0},
{11, 5, 0}, {0, 0, 0}};
if (memcmp(rgba, rgb565, 3 * sizeof(fb_bitfield)) == 0) {
format = QImage::Format_RGB16;
} else if (memcmp(rgba, bgr565, 3 * sizeof(fb_bitfield)) == 0) {
format = QImage::Format_RGB16;
// pixeltype = BGRPixel;
}
break;
}
case 15: {
const fb_bitfield rgb1555[4] = {{10, 5, 0}, {5, 5, 0},
{0, 5, 0}, {15, 1, 0}};
const fb_bitfield bgr1555[4] = {{0, 5, 0}, {5, 5, 0},
{10, 5, 0}, {15, 1, 0}};
if (memcmp(rgba, rgb1555, 3 * sizeof(fb_bitfield)) == 0) {
format = QImage::Format_RGB555;
} else if (memcmp(rgba, bgr1555, 3 * sizeof(fb_bitfield)) == 0) {
format = QImage::Format_RGB555;
// pixeltype = BGRPixel;
}
break;
}
case 12: {
const fb_bitfield rgb444[4] = {{8, 4, 0}, {4, 4, 0},
{0, 4, 0}, {0, 0, 0}};
if (memcmp(rgba, rgb444, 3 * sizeof(fb_bitfield)) == 0)
format = QImage::Format_RGB444;
break;
}
case 8:
break;
case 1:
format = QImage::Format_Mono; //###: LSB???
break;
default:
break;
}
return format;
}
static int openTtyDevice(const QString &device)
{
const char *const devs[] = { "/dev/tty0", "/dev/tty", "/dev/console", nullptr };
int fd = -1;
if (device.isEmpty()) {
for (const char * const *dev = devs; *dev; ++dev) {
fd = QT_OPEN(*dev, O_RDWR);
if (fd != -1)
break;
}
} else {
fd = QT_OPEN(QFile::encodeName(device).constData(), O_RDWR);
}
return fd;
}
static void switchToGraphicsMode(int ttyfd, bool doSwitch, int *oldMode)
{
// Do not warn if the switch fails: the ioctl fails when launching from a
// remote console and there is nothing we can do about it. The matching
// call in resetTty should at least fail then, too, so we do no harm.
if (ioctl(ttyfd, KDGETMODE, oldMode) == 0) {
if (doSwitch && *oldMode != KD_GRAPHICS)
ioctl(ttyfd, KDSETMODE, KD_GRAPHICS);
}
}
static void resetTty(int ttyfd, int oldMode)
{
ioctl(ttyfd, KDSETMODE, oldMode);
QT_CLOSE(ttyfd);
}
static void blankScreen(int fd, bool on)
{
ioctl(fd, FBIOBLANK, on ? VESA_POWERDOWN : VESA_NO_BLANKING);
}
QLinuxFbScreen::QLinuxFbScreen(const QStringList &args)
: mArgs(args), mFbFd(-1), mTtyFd(-1), mBlitter(nullptr)
{
mMmap.data = nullptr;
}
QLinuxFbScreen::~QLinuxFbScreen()
{
if (mFbFd != -1) {
if (mMmap.data)
munmap(mMmap.data - mMmap.offset, mMmap.size);
close(mFbFd);
}
if (mTtyFd != -1)
resetTty(mTtyFd, mOldTtyMode);
delete mBlitter;
}
bool QLinuxFbScreen::initialize()
{
QRegularExpression ttyRx("tty=(.*)"_L1);
QRegularExpression fbRx("fb=(.*)"_L1);
QRegularExpression mmSizeRx("mmsize=(\\d+)x(\\d+)"_L1);
QRegularExpression sizeRx("size=(\\d+)x(\\d+)"_L1);
QRegularExpression offsetRx("offset=(\\d+)x(\\d+)"_L1);
QString fbDevice, ttyDevice;
QSize userMmSize;
QRect userGeometry;
bool doSwitchToGraphicsMode = true;
// Parse arguments
for (const QString &arg : std::as_const(mArgs)) {
QRegularExpressionMatch match;
if (arg == "nographicsmodeswitch"_L1)
doSwitchToGraphicsMode = false;
else if (arg.contains(mmSizeRx, &match))
userMmSize = QSize(match.captured(1).toInt(), match.captured(2).toInt());
else if (arg.contains(sizeRx, &match))
userGeometry.setSize(QSize(match.captured(1).toInt(), match.captured(2).toInt()));
else if (arg.contains(offsetRx, &match))
userGeometry.setTopLeft(QPoint(match.captured(1).toInt(), match.captured(2).toInt()));
else if (arg.contains(ttyRx, &match))
ttyDevice = match.captured(1);
else if (arg.contains(fbRx, &match))
fbDevice = match.captured(1);
}
if (fbDevice.isEmpty()) {
fbDevice = "/dev/fb0"_L1;
if (!QFile::exists(fbDevice))
fbDevice = "/dev/graphics/fb0"_L1;
if (!QFile::exists(fbDevice)) {
qWarning("Unable to figure out framebuffer device. Specify it manually.");
return false;
}
}
// Open the device
mFbFd = openFramebufferDevice(fbDevice);
if (mFbFd == -1) {
qErrnoWarning(errno, "Failed to open framebuffer %s", qPrintable(fbDevice));
return false;
}
// Read the fixed and variable screen information
fb_fix_screeninfo finfo;
fb_var_screeninfo vinfo;
memset(&vinfo, 0, sizeof(vinfo));
memset(&finfo, 0, sizeof(finfo));
if (ioctl(mFbFd, FBIOGET_FSCREENINFO, &finfo) != 0) {
qErrnoWarning(errno, "Error reading fixed information");
return false;
}
if (ioctl(mFbFd, FBIOGET_VSCREENINFO, &vinfo)) {
qErrnoWarning(errno, "Error reading variable information");
return false;
}
mDepth = determineDepth(vinfo);
mBytesPerLine = finfo.line_length;
QRect geometry = determineGeometry(vinfo, userGeometry);
mGeometry = QRect(QPoint(0, 0), geometry.size());
mFormat = determineFormat(vinfo, mDepth);
if (mFormat == QImage::Format_Invalid) {
qWarning("Unsupported framebuffer format: depth %d, RGB offset/length %u/%u %u/%u %u/%u",
mDepth, vinfo.red.offset, vinfo.red.length, vinfo.green.offset, vinfo.green.length,
vinfo.blue.offset, vinfo.blue.length);
return false;
}
mPhysicalSize = determinePhysicalSize(vinfo, userMmSize, geometry.size());
// mmap the framebuffer
mMmap.size = finfo.smem_len;
uchar *data = (unsigned char *)mmap(nullptr, mMmap.size, PROT_READ | PROT_WRITE, MAP_SHARED, mFbFd, 0);
if ((long)data == -1) {
qErrnoWarning(errno, "Failed to mmap framebuffer");
return false;
}
mMmap.offset = geometry.y() * mBytesPerLine + geometry.x() * mDepth / 8;
mMmap.data = data + mMmap.offset;
QFbScreen::initializeCompositor();
mFbScreenImage = QImage(mMmap.data, geometry.width(), geometry.height(), mBytesPerLine, mFormat);
mCursor = new QFbCursor(this);
mTtyFd = openTtyDevice(ttyDevice);
if (mTtyFd == -1)
qErrnoWarning(errno, "Failed to open tty");
switchToGraphicsMode(mTtyFd, doSwitchToGraphicsMode, &mOldTtyMode);
blankScreen(mFbFd, false);
return true;
}
QRegion QLinuxFbScreen::doRedraw()
{
QRegion touched = QFbScreen::doRedraw();
if (touched.isEmpty())
return touched;
if (!mBlitter)
mBlitter = new QPainter(&mFbScreenImage);
mBlitter->setCompositionMode(QPainter::CompositionMode_Source);
for (const QRect &rect : touched)
mBlitter->drawImage(rect, mScreenImage, rect);
return touched;
}
// grabWindow() grabs "from the screen" not from the backingstores.
// In linuxfb's case it will also include the mouse cursor.
QPixmap QLinuxFbScreen::grabWindow(WId wid, int x, int y, int width, int height) const
{
if (!wid) {
if (width < 0)
width = mFbScreenImage.width() - x;
if (height < 0)
height = mFbScreenImage.height() - y;
return QPixmap::fromImage(mFbScreenImage).copy(x, y, width, height);
}
QFbWindow *window = windowForId(wid);
if (window) {
const QRect geom = window->geometry();
if (width < 0)
width = geom.width() - x;
if (height < 0)
height = geom.height() - y;
QRect rect(geom.topLeft() + QPoint(x, y), QSize(width, height));
rect &= window->geometry();
return QPixmap::fromImage(mFbScreenImage).copy(rect);
}
return QPixmap();
}
QT_END_NAMESPACE
#include "moc_qlinuxfbscreen.cpp"