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-rw-r--r--kfile-plugins/png/kfile_png.cpp315
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diff --git a/kfile-plugins/png/kfile_png.cpp b/kfile-plugins/png/kfile_png.cpp
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+/* This file is part of the KDE project
+ * Copyright (C) 2001, 2002 Rolf Magnus <ramagnus@kde.org>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License as published by the Free Software Foundation version 2.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; see the file COPYING. If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ * Boston, MA 02110-1301, USA.
+ *
+ * $Id$
+ */
+
+#include <stdlib.h>
+#include "kfile_png.h"
+
+#include <kurl.h>
+#include <kprocess.h>
+#include <klocale.h>
+#include <kgenericfactory.h>
+#include <kdebug.h>
+
+#include <qcstring.h>
+#include <qfile.h>
+#include <qdatetime.h>
+#include <qdict.h>
+#include <qvalidator.h>
+#include <zlib.h>
+
+// some defines to make it easier
+// don't tell me anything about preprocessor usage :)
+#define CHUNK_SIZE(data, index) ((data[index ]<<24) + (data[index+1]<<16) + \
+ (data[index+2]<< 8) + data[index+3])
+#define CHUNK_TYPE(data, index) &data[index+4]
+#define CHUNK_HEADER_SIZE 12
+#define CHUNK_DATA(data, index, offset) data[8+index+offset]
+
+// known translations for common png keys
+static const char* knownTranslations[]
+#ifdef __GNUC__
+__attribute__((unused))
+#endif
+ = {
+ I18N_NOOP("Title"),
+ I18N_NOOP("Author"),
+ I18N_NOOP("Description"),
+ I18N_NOOP("Copyright"),
+ I18N_NOOP("Creation Time"),
+ I18N_NOOP("Software"),
+ I18N_NOOP("Disclaimer"),
+ I18N_NOOP("Warning"),
+ I18N_NOOP("Source"),
+ I18N_NOOP("Comment")
+};
+
+// and for the colors
+static const char* colors[] = {
+ I18N_NOOP("Grayscale"),
+ I18N_NOOP("Unknown"),
+ I18N_NOOP("RGB"),
+ I18N_NOOP("Palette"),
+ I18N_NOOP("Grayscale/Alpha"),
+ I18N_NOOP("Unknown"),
+ I18N_NOOP("RGB/Alpha")
+};
+
+ // and compressions
+static const char* compressions[] =
+{
+ I18N_NOOP("Deflate")
+};
+
+ // interlaced modes
+static const char* interlaceModes[] = {
+ I18N_NOOP("None"),
+ I18N_NOOP("Adam7")
+};
+
+typedef KGenericFactory<KPngPlugin> PngFactory;
+
+K_EXPORT_COMPONENT_FACTORY(kfile_png, PngFactory("kfile_png"))
+
+KPngPlugin::KPngPlugin(QObject *parent, const char *name,
+ const QStringList &args)
+ : KFilePlugin(parent, name, args)
+{
+ kdDebug(7034) << "png plugin\n";
+
+ // set up our mime type
+ KFileMimeTypeInfo* info = addMimeTypeInfo( "image/png" );
+
+ KFileMimeTypeInfo::GroupInfo* group = 0;
+ KFileMimeTypeInfo::ItemInfo* item = 0;
+
+ // comment group
+ group = addGroupInfo(info, "Comment", i18n("Comment"));
+ addVariableInfo(group, QVariant::String, 0);
+
+ // technical group
+ group = addGroupInfo(info, "Technical", i18n("Technical Details"));
+
+ item = addItemInfo(group, "Dimensions", i18n("Dimensions"), QVariant::Size);
+ setHint( item, KFileMimeTypeInfo::Size );
+ setUnit(item, KFileMimeTypeInfo::Pixels);
+
+ item = addItemInfo(group, "BitDepth", i18n("Bit Depth"), QVariant::Int);
+ setUnit(item, KFileMimeTypeInfo::BitsPerPixel);
+
+ addItemInfo(group, "ColorMode", i18n("Color Mode"), QVariant::String);
+ addItemInfo(group, "Compression", i18n("Compression"), QVariant::String);
+ addItemInfo(group, "InterlaceMode", i18n("Interlace Mode"),QVariant::String);
+}
+
+bool KPngPlugin::readInfo( KFileMetaInfo& info, uint what)
+{
+ if ( info.path().isEmpty() ) // remote file
+ return false;
+ QFile f(info.path());
+ if ( !f.open(IO_ReadOnly) )
+ return false;
+
+ QIODevice::Offset fileSize = f.size();
+
+ if (fileSize < 29) return false;
+ // the technical group will be read from the first 29 bytes. If the file
+ // is smaller, we can't even read this.
+
+ bool readComments = false;
+ if (what & (KFileMetaInfo::Fastest |
+ KFileMetaInfo::DontCare |
+ KFileMetaInfo::ContentInfo)) readComments = true;
+ else
+ fileSize = 29; // No need to read more
+
+ uchar *data = new uchar[fileSize+1];
+ f.readBlock(reinterpret_cast<char*>(data), fileSize);
+ data[fileSize]='\n';
+
+ // find the start
+ if (data[0] == 137 && data[1] == 80 && data[2] == 78 && data[3] == 71 &&
+ data[4] == 13 && data[5] == 10 && data[6] == 26 && data[7] == 10 )
+ {
+ // ok
+ // the IHDR chunk should be the first
+ if (!strncmp((char*)&data[12], "IHDR", 4))
+ {
+ // we found it, get the dimensions
+ ulong x,y;
+ x = (data[16]<<24) + (data[17]<<16) + (data[18]<<8) + data[19];
+ y = (data[20]<<24) + (data[21]<<16) + (data[22]<<8) + data[23];
+
+ uint type = data[25];
+ uint bpp = data[24];
+ kdDebug(7034) << "dimensions " << x << "*" << y << endl;
+
+ // the bpp are only per channel, so we need to multiply the with
+ // the channel count
+ switch (type)
+ {
+ case 0: break; // Grayscale
+ case 2: bpp *= 3; break; // RGB
+ case 3: break; // palette
+ case 4: bpp *= 2; break; // grayscale w. alpha
+ case 6: bpp *= 4; break; // RGBA
+
+ default: // we don't get any sensible value here
+ bpp = 0;
+ }
+
+ KFileMetaInfoGroup techgroup = appendGroup(info, "Technical");
+
+ appendItem(techgroup, "Dimensions", QSize(x, y));
+ appendItem(techgroup, "BitDepth", bpp);
+ appendItem(techgroup, "ColorMode",
+ (type < sizeof(colors)/sizeof(colors[0]))
+ ? i18n(colors[data[25]]) : i18n("Unknown"));
+
+ appendItem(techgroup, "Compression",
+ (data[26] < sizeof(compressions)/sizeof(compressions[0]))
+ ? i18n(compressions[data[26]]) : i18n("Unknown"));
+
+ appendItem(techgroup, "InterlaceMode",
+ (data[28] < sizeof(interlaceModes)/sizeof(interlaceModes[0]))
+ ? i18n(interlaceModes[data[28]]) : i18n("Unknown"));
+ }
+
+ // look for a tEXt chunk
+ if (readComments)
+ {
+ uint index = 8;
+ index += CHUNK_SIZE(data, index) + CHUNK_HEADER_SIZE;
+ KFileMetaInfoGroup commentGroup = appendGroup(info, "Comment");
+
+ while(index<fileSize-12)
+ {
+ while (index < fileSize - 12 &&
+ strncmp((char*)CHUNK_TYPE(data,index), "tEXt", 4) &&
+ strncmp((char*)CHUNK_TYPE(data,index), "zTXt", 4))
+
+ {
+ if (!strncmp((char*)CHUNK_TYPE(data,index), "IEND", 4))
+ goto end;
+
+ index += CHUNK_SIZE(data, index) + CHUNK_HEADER_SIZE;
+ }
+
+ if (index < fileSize - 12)
+ {
+ // we found a tEXt or zTXt field
+
+ // get the key, it's a null terminated string at the
+ // chunk start
+
+ uchar* key = &CHUNK_DATA(data,index,0);
+
+ int keysize=0;
+ for (;key[keysize]!=0; keysize++)
+ // look if we reached the end of the file
+ // (it might be corrupted)
+ if (8+index+keysize>=fileSize)
+ goto end;
+
+ QByteArray arr;
+ if(!strncmp((char*)CHUNK_TYPE(data,index), "zTXt", 4)) {
+ kdDebug(7034) << "We found a zTXt field\n";
+ // we get the compression method after the key
+ uchar* compressionMethod = &CHUNK_DATA(data,index,keysize+1);
+ if ( *compressionMethod != 0x00 ) {
+ // then it isn't zlib compressed and we are sunk
+ kdDebug(7034) << "Non-standard compression method." << endl;
+ goto end;
+ }
+ // compressed string after the compression technique spec
+ uchar* compressedText = &CHUNK_DATA(data, index, keysize+2);
+ uint compressedTextSize = CHUNK_SIZE(data, index)-keysize-2;
+
+ // security check, also considering overflow wraparound from the addition --
+ // we may endup with a /smaller/ index if we wrap all the way around
+ uint firstIndex = (uint)(compressedText - data);
+ uint onePastLastIndex = firstIndex + compressedTextSize;
+ if ( onePastLastIndex > fileSize || onePastLastIndex <= firstIndex)
+ goto end;
+
+ uLongf uncompressedLen = compressedTextSize * 2; // just a starting point
+ int zlibResult;
+ do {
+ arr.resize(uncompressedLen);
+ zlibResult = uncompress((Bytef*)arr.data(), &uncompressedLen,
+ compressedText, compressedTextSize);
+ if (Z_OK == zlibResult) {
+ // then it is all OK
+ arr.resize(uncompressedLen);
+ } else if (Z_BUF_ERROR == zlibResult) {
+ // the uncompressedArray needs to be larger
+ // kdDebug(7034) << "doubling size for decompression" << endl;
+ uncompressedLen *= 2;
+
+ // DoS protection. can't be bigger than 64k
+ if ( uncompressedLen > 131072 )
+ break;
+ } else {
+ // something bad happened
+ goto end;
+ }
+ } while (Z_BUF_ERROR == zlibResult);
+
+ if (Z_OK != zlibResult)
+ goto end;
+ } else if (!strncmp((char*)CHUNK_TYPE(data,index), "tEXt", 4)) {
+ kdDebug(7034) << "We found a tEXt field\n";
+ // the text comes after the key, but isn't null terminated
+ uchar* text = &CHUNK_DATA(data,index, keysize+1);
+ uint textsize = CHUNK_SIZE(data, index)-keysize-1;
+
+ // security check, also considering overflow wraparound from the addition --
+ // we may endup with a /smaller/ index if we wrap all the way around
+ uint firstIndex = (uint)(text - data);
+ uint onePastLastIndex = firstIndex + textsize;
+
+ if ( onePastLastIndex > fileSize || onePastLastIndex <= firstIndex)
+ goto end;
+
+ arr.resize(textsize);
+ arr = QByteArray(textsize).duplicate((const char*)text,
+ textsize);
+
+ } else {
+ kdDebug(7034) << "We found a field, not expected though\n";
+ goto end;
+ }
+ appendItem(commentGroup,
+ QString(reinterpret_cast<char*>(key)),
+ QString(arr));
+
+ kdDebug(7034) << "adding " << key << " / "
+ << QString(arr) << endl;
+
+ index += CHUNK_SIZE(data, index) + CHUNK_HEADER_SIZE;
+ }
+ }
+ }
+ }
+end:
+ delete[] data;
+ return true;
+}
+
+#include "kfile_png.moc"