Make libpnd a little more tolerant of padding at end of PXML, when looking for icon

diff --git a/lib/pnd_discovery.c b/lib/pnd_discovery.c
index 594a03e..73ed18e 100644 (file)
--- a/lib/pnd_discovery.c
+++ b/lib/pnd_discovery.c
@@ -122,11 +122,27 @@ static int pnd_disco_callback ( const char *fpath, const struct stat *sb,
       char pngbuffer [ 16 ]; // \211 P N G \r \n \032 \n
       pngbuffer [ 0 ] = 137;      pngbuffer [ 1 ] = 80;      pngbuffer [ 2 ] = 78;      pngbuffer [ 3 ] = 71;
       pngbuffer [ 4 ] = 13;       pngbuffer [ 5 ] = 10;       pngbuffer [ 6 ] = 26;      pngbuffer [ 7 ] = 10;
-      if ( fread ( pngbuffer + 8, 8, 1, f ) == 1 ) {
-       if ( memcmp ( pngbuffer, pngbuffer + 8, 8 ) == 0 ) {
-         pxml_close_pos = pos;
-       }
+
+      unsigned char padtests = 10;
+      unsigned int padstart = ftell ( f );
+      while ( padtests ) {
+
+       if ( fread ( pngbuffer + 8, 8, 1, f ) == 1 ) {
+         if ( memcmp ( pngbuffer, pngbuffer + 8, 8 ) == 0 ) {
+           pxml_close_pos = pos;
+           break;
+         } // if
+         fseek ( f, -7, SEEK_CUR ); // seek back 7 (so we're 1 further than we started, since PNG header is 8b)
+       } // if read
+
+       padtests --;
+      } // while
+
+      if ( ! padtests ) {
+       // no icon found, so back to where we started looking
+       fseek ( f, padstart, SEEK_SET );
       }
+
     } // icon
 #endif