fix for BMP/ICO magic detection

git-svn-id: https://svn.berlios.de/svnroot/repos/yacy/trunk@3991 6c8d7289-2bf4-0310-a012-ef5d649a1542

source/de/anomic/ymage/ymageBMPParser.java

@@ -52,7 +52,7 @@ public class ymageBMPParser {
     
     public static final boolean isBMP(byte[] source) {
         // check the file magic
-        return (source[0] == 'B') && (source[1] == 'M');
+        return (source != null) && (source.length >= 2) && (source[0] == 'B') && (source[1] == 'M');
     }
     
     public ymageBMPParser(byte[] source) {

source/de/anomic/ymage/ymageICOParser.java

@@ -44,7 +44,7 @@ public class ymageICOParser {
     
     public static final boolean isICO(byte[] source) {
         // check the file magic
-        return (source[0] == 0) && (source[1] == 0) && (source[2] == 1) && (source[3] == 0);
+        return (source != null) && (source.length >= 4) && (source[0] == 0) && (source[1] == 0) && (source[2] == 1) && (source[3] == 0);
     }
     
     public ymageICOParser(byte[] source) {