src/gui/image/qxbmhandler.cpp
changeset 0 1918ee327afb
child 3 41300fa6a67c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/gui/image/qxbmhandler.cpp	Mon Jan 11 14:00:40 2010 +0000
@@ -0,0 +1,350 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the QtGui module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <qplatformdefs.h>
+#include "private/qxbmhandler_p.h"
+
+#ifndef QT_NO_IMAGEFORMAT_XBM
+
+#include <qimage.h>
+#include <qiodevice.h>
+#include <qvariant.h>
+
+#include <stdio.h>
+#include <ctype.h>
+
+QT_BEGIN_NAMESPACE
+
+/*****************************************************************************
+  X bitmap image read/write functions
+ *****************************************************************************/
+
+static inline int hex2byte(register char *p)
+{
+    return ((isdigit((uchar) *p) ? *p - '0' : toupper((uchar) *p) - 'A' + 10) << 4) |
+           (isdigit((uchar) *(p+1)) ? *(p+1) - '0' : toupper((uchar) *(p+1)) - 'A' + 10);
+}
+
+static bool read_xbm_header(QIODevice *device, int& w, int& h)
+{
+    const int buflen = 300;
+    char buf[buflen + 1];
+    QRegExp r1(QLatin1String("^#define[ \t]+[a-zA-Z0-9._]+[ \t]+"));
+    QRegExp r2(QLatin1String("[0-9]+"));
+
+    qint64 readBytes = 0;
+
+    // "#define .._width <num>"
+    readBytes = device->readLine(buf, buflen);
+    if (readBytes <= 0)
+	return false;
+    buf[readBytes - 1] = '\0';
+
+    // skip initial comment, if any
+    while (buf[0] != '#' && (readBytes = device->readLine( buf, buflen )) > 0) {}
+
+    if (readBytes <= 0)
+	return false;
+    buf[readBytes - 1] = '\0';
+    QString sbuf;
+    sbuf = QString::fromLatin1(buf);
+
+    if (r1.indexIn(sbuf) == 0 &&
+         r2.indexIn(sbuf, r1.matchedLength()) == r1.matchedLength())
+        w = QByteArray(&buf[r1.matchedLength()]).trimmed().toInt();
+
+    // "#define .._height <num>"
+    readBytes = device->readLine(buf, buflen);
+    if (readBytes <= 0)
+	return false;
+    buf[readBytes - 1] = '\0';
+
+    sbuf = QString::fromLatin1(buf);
+
+    if (r1.indexIn(sbuf) == 0 &&
+         r2.indexIn(sbuf, r1.matchedLength()) == r1.matchedLength())
+        h = QByteArray(&buf[r1.matchedLength()]).trimmed().toInt();
+
+    // format error
+    if (w <= 0 || w > 32767 || h <= 0 || h > 32767)
+        return false;
+
+    return true;
+}
+
+static bool read_xbm_body(QIODevice *device, int w, int h, QImage *outImage)
+{
+    const int buflen = 300;
+    char buf[buflen + 1];
+
+    qint64 readBytes = 0;
+
+    // scan for database
+    for (;;) {
+        if ((readBytes = device->readLine(buf, buflen)) <= 0) {
+            // end of file
+            return false;
+        }
+
+        buf[readBytes] = '\0';
+        if (QByteArray::fromRawData(buf, readBytes).contains("0x"))
+            break;
+    }
+
+    if (outImage->size() != QSize(w, h) || outImage->format() != QImage::Format_MonoLSB) {
+        *outImage = QImage(w, h, QImage::Format_MonoLSB);
+        if (outImage->isNull())
+            return false;
+    }
+
+    outImage->setNumColors(2);
+    outImage->setColor(0, qRgb(255,255,255));        // white
+    outImage->setColor(1, qRgb(0,0,0));                // black
+
+    int           x = 0, y = 0;
+    uchar *b = outImage->scanLine(0);
+    char  *p = buf + QByteArray::fromRawData(buf, readBytes).indexOf("0x");
+    w = (w+7)/8;                                // byte width
+
+    while (y < h) {                                // for all encoded bytes...
+        if (p) {                                // p = "0x.."
+            *b++ = hex2byte(p+2);
+            p += 2;
+            if (++x == w && ++y < h) {
+                b = outImage->scanLine(y);
+                x = 0;
+            }
+            p = strstr(p, "0x");
+        } else {                                // read another line
+            if ((readBytes = device->readLine(buf,buflen)) <= 0)        // EOF ==> truncated image
+                break;
+            p = buf + QByteArray::fromRawData(buf, readBytes).indexOf("0x");
+        }
+    }
+
+    return true;
+}
+
+static bool read_xbm_image(QIODevice *device, QImage *outImage)
+{
+    int w = 0, h = 0;
+    if (!read_xbm_header(device, w, h))
+        return false;
+    return read_xbm_body(device, w, h, outImage);
+}
+
+static bool write_xbm_image(const QImage &sourceImage, QIODevice *device, const QString &fileName)
+{
+    QImage image = sourceImage;
+    int	       w = image.width();
+    int	       h = image.height();
+    int	       i;
+    QString    s = fileName; // get file base name
+    int        msize = s.length() + 100;
+    char *buf = new char[msize];
+
+    qsnprintf(buf, msize, "#define %s_width %d\n", s.toAscii().data(), w);
+    device->write(buf, qstrlen(buf));
+    qsnprintf(buf, msize, "#define %s_height %d\n", s.toAscii().data(), h);
+    device->write(buf, qstrlen(buf));
+    qsnprintf(buf, msize, "static char %s_bits[] = {\n ", s.toAscii().data());
+    device->write(buf, qstrlen(buf));
+
+    if (image.format() != QImage::Format_MonoLSB)
+        image = image.convertToFormat(QImage::Format_MonoLSB);
+
+    bool invert = qGray(image.color(0)) < qGray(image.color(1));
+    char hexrep[16];
+    for (i=0; i<10; i++)
+	hexrep[i] = '0' + i;
+    for (i=10; i<16; i++)
+	hexrep[i] = 'a' -10 + i;
+    if (invert) {
+	char t;
+	for (i=0; i<8; i++) {
+	    t = hexrep[15-i];
+	    hexrep[15-i] = hexrep[i];
+	    hexrep[i] = t;
+	}
+    }
+    int bcnt = 0;
+    register char *p = buf;
+    int bpl = (w+7)/8;
+    for (int y = 0; y < h; ++y) {
+        uchar *b = image.scanLine(y);
+        for (i = 0; i < bpl; ++i) {
+            *p++ = '0'; *p++ = 'x';
+            *p++ = hexrep[*b >> 4];
+            *p++ = hexrep[*b++ & 0xf];
+
+            if (i < bpl - 1 || y < h - 1) {
+                *p++ = ',';
+                if (++bcnt > 14) {
+                    *p++ = '\n';
+                    *p++ = ' ';
+                    *p   = '\0';
+                    if ((int)qstrlen(buf) != device->write(buf, qstrlen(buf))) {
+                        delete [] buf;
+                        return false;
+                    }
+                    p = buf;
+                    bcnt = 0;
+                }
+            }
+        }
+    }
+#if defined(_MSC_VER) && _MSC_VER >= 1400
+    strcpy_s(p, sizeof(" };\n"), " };\n");
+#else
+    strcpy(p, " };\n");
+#endif
+    if ((int)qstrlen(buf) != device->write(buf, qstrlen(buf))) {
+        delete [] buf;
+        return false;
+    }
+
+    delete [] buf;
+    return true;
+}
+
+QXbmHandler::QXbmHandler()
+    : state(Ready)
+{
+}
+
+bool QXbmHandler::readHeader()
+{
+    state = Error;
+    if (!read_xbm_header(device(), width, height))
+        return false;
+    state = ReadHeader;
+    return true;
+}
+
+bool QXbmHandler::canRead() const
+{
+    if (state == Ready) {
+        if (!canRead(device()))
+            return false;
+        setFormat("xbm");
+        return true;
+    }
+    return state != Error;
+}
+
+bool QXbmHandler::canRead(QIODevice *device)
+{
+    QImage image;
+
+    // it's impossible to tell whether we can load an XBM or not when
+    // it's from a sequential device, as the only way to do it is to
+    // attempt to parse the whole image.
+    if (device->isSequential())
+        return false;
+
+    qint64 oldPos = device->pos();
+    bool success = read_xbm_image(device, &image);
+    device->seek(oldPos);
+
+    return success;
+}
+
+bool QXbmHandler::read(QImage *image)
+{
+    if (state == Error)
+        return false;
+    
+    if (state == Ready && !readHeader()) {
+        state = Error;
+        return false;
+    }
+
+    if (!read_xbm_body(device(), width, height, image)) {
+        state = Error;
+        return false;
+    }
+
+    state = Ready;
+    return true;
+}
+
+bool QXbmHandler::write(const QImage &image)
+{
+    return write_xbm_image(image, device(), fileName);
+}
+
+bool QXbmHandler::supportsOption(ImageOption option) const
+{
+    return option == Name
+        || option == Size
+        || option == ImageFormat;
+}
+
+QVariant QXbmHandler::option(ImageOption option) const
+{
+    if (option == Name) {
+        return fileName;
+    } else if (option == Size) {
+        if (state == Error)
+            return QVariant();
+        if (state == Ready && !const_cast<QXbmHandler*>(this)->readHeader())
+            return QVariant();
+        return QSize(width, height);
+    } else if (option == ImageFormat) {
+        return QImage::Format_MonoLSB;
+    }
+    return QVariant();
+}
+
+void QXbmHandler::setOption(ImageOption option, const QVariant &value)
+{
+    if (option == Name)
+        fileName = value.toString();
+}
+
+QByteArray QXbmHandler::name() const
+{
+    return "xbm";
+}
+
+QT_END_NAMESPACE
+
+#endif // QT_NO_IMAGEFORMAT_XBM