Re: [cp-patches] Patch: minor ZipFile improvement

[Anthony Green]

On Thu, 2005-09-15 at 07:27 -0600, Tom Tromey wrote:
> Actually we ought to try reading until we get all 4 bytes or see EOF.
> A short read is valid and not an error.

Ok, how about this?

2005-09-14  Anthony Green  <address@hidden>

        * java/util/zip/ZipFile.java (checkZipFile): Make sure we read all
        4 bytes of the magic number.

Index: java/util/zip/ZipFile.java
===================================================================
RCS file: /cvsroot/classpath/classpath/java/util/zip/ZipFile.java,v
retrieving revision 1.26
diff -u -r1.26 ZipFile.java
--- java/util/zip/ZipFile.java  13 Sep 2005 22:19:15 -0000      1.26
+++ java/util/zip/ZipFile.java  15 Sep 2005 15:03:56 -0000
@@ -144,9 +144,18 @@
   private void checkZipFile() throws IOException, ZipException
   {
     byte[] magicBuf = new byte[4];
-    raf.read(magicBuf);
+    boolean validRead = true;
 
-    if (readLeInt(magicBuf, 0) != LOCSIG)
+    try 
+      {
+       raf.readFully (magicBuf);
+      } 
+    catch (EOFException) 
+      {
+       validRead = false;
+      } 
+
+    if (validRead == false || readLeInt(magicBuf, 0) != LOCSIG)
       {
        raf.close();
        throw new ZipException("Not a valid zip file");