fixed a possible crasher

1 files changed, 2 insertions, 1 deletions

diff --git a/noncore/graphics/opie-eye/slave/png_slave.cpp b/noncore/graphics/opie-eye/slave/png_slave.cpp
index 86e1cdc..21555b4 100644
--- a/noncore/graphics/opie-eye/slave/png_slave.cpp
+++ b/noncore/graphics/opie-eye/slave/png_slave.cpp
@@ -1,165 +1,166 @@
 #include "png_slave.h"
 
 #include "thumbnailtool.h"
 
 #include <qobject.h>
 #include <qfile.h>
 #include <qimage.h>
 #include <qpixmap.h>
 #include <qstring.h>
 
 /*
  * GPLv2 from kfile plugin
  */
 PHUNK_VIEW_INTERFACE( "PNG", PNGSlave );
 
 #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]
 
 /* TRANSLATOR QObject */
 
 // known translations for common png keys
 static const char* knownTranslations[]
 #ifdef __GNUC__
 __attribute__((unused))
 #endif
  = {
   QT_TR_NOOP("Title"),
   QT_TR_NOOP("Author"),
   QT_TR_NOOP("Description"),
   QT_TR_NOOP("Copyright"),
   QT_TR_NOOP("Creation Time"),
   QT_TR_NOOP("Software"),
   QT_TR_NOOP("Disclaimer"),
   QT_TR_NOOP("Warning"),
   QT_TR_NOOP("Source"),
   QT_TR_NOOP("Comment")
 };
 
 // and for the colors
 static const char* colors[] = {
   QT_TR_NOOP("Grayscale"),
   QT_TR_NOOP("Unknown"),
   QT_TR_NOOP("RGB"),
   QT_TR_NOOP("Palette"),
   QT_TR_NOOP("Grayscale/Alpha"),
   QT_TR_NOOP("Unknown"),
   QT_TR_NOOP("RGB/Alpha")
 };
 
   // and compressions
 static const char* compressions[] =
 {
   QT_TR_NOOP("Deflate")
 };
 
   // interlaced modes
 static const char* interlaceModes[] = {
   QT_TR_NOOP("None"),
   QT_TR_NOOP("Adam7")
 };
 
 
 static void read_comment( const QString& inf,
                           bool readComments,  QString& str ) {
     QFile f(inf);
-    f.open(IO_ReadOnly);
+    if (!f.exists()) return;
+    if (!f.open(IO_ReadOnly)) return;
 
     if (f.size() < 26) return;
     // the technical group will be read from the first 26 bytes. If the file
     // is smaller, we can't even read this.
 
     uchar *data = new uchar[f.size()+1];
     f.readBlock(reinterpret_cast<char*>(data), f.size());
     data[f.size()]='\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];
 
             // 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;
             }
 
 
             str  = QObject::tr("Dimensions: %1x%2\n" ).arg(x).arg(y);
             str += QObject::tr("Depth: %1\n" ).arg(bpp);
             str += QObject::tr("ColorMode: %1\n").arg(
                        (type < sizeof(colors)/sizeof(colors[0]))
                        ? QObject::tr(colors[data[25]]) : QObject::tr("Unknown") );
 
             str += QObject::tr("Compression: %1\n").arg(
                        (data[26] < sizeof(compressions)/sizeof(compressions[0]))
                        ? QObject::tr(compressions[data[26]]) : QObject::tr("Unknown") );
 
             str += QObject::tr("InterlaceMode: %1\n" ).arg(
                        (data[28] < sizeof(interlaceModes)/sizeof(interlaceModes[0]))
                        ? QObject::tr(interlaceModes[data[28]]) : QObject::tr("Unknown"));
         }
 
         if ( readComments ) {
             uint index = 8;
             index += CHUNK_SIZE(data, index) + CHUNK_HEADER_SIZE;
 
             while(index<f.size()-12)
             {
                 while (index < f.size() - 12 &&
                        strncmp((char*)CHUNK_TYPE(data,index), "tEXt", 4))
                 {
                     if (!strncmp((char*)CHUNK_TYPE(data,index), "IEND", 4))
                         goto end;
 
                     index += CHUNK_SIZE(data, index) + CHUNK_HEADER_SIZE;
                 }
 
                 if (index < f.size() - 12)
                 {
                     // we found a tEXt 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>=f.size())
                             goto end;
 
                     // 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 > f.size() || onePastLastIndex <= firstIndex)
                         goto end;