BufferedInputStream.mark()

[Guilhem Lavaux]

Hi,

I've been trying to make azureus work with kaffe and apparently they use 
an hidden feature of sun's jdk: it is capable to do 
mark(Integer.MAX_VALUE). So I modified the mark() logic to be able to 
allocate buffers incrementally.

Please review.

Here is the changelog:

2004-03-06  Guilhem Lavaux <address@hidden>

       * libraries/javalib/java/io/BufferedInputStream.java
       (mark, refill) Make an incremental mark buffer allocation.
       New field marktarget, CHUNKSIZE.

Cheers,
Guilhem.

Index: java/io/BufferedInputStream.java
===================================================================
RCS file: /cvsroot/classpath/classpath/java/io/BufferedInputStream.java,v
retrieving revision 1.10
diff -u -r1.10 BufferedInputStream.java
--- java/io/BufferedInputStream.java    22 Jan 2002 22:26:59 -0000      1.10
+++ java/io/BufferedInputStream.java    6 Mar 2004 18:29:28 -0000
@@ -103,6 +103,19 @@
   protected int marklimit = 0;
 
   /**
+   * This is the maximum size we have to allocate for the mark buffer.
+   * This number may be huge (Integer.MAX_VALUE). The class will continue
+   * to allocate new chunks (specified by <code>CHUNKSIZE</code>) until the
+   * the size specified by this field is achieved.
+   */
+  protected int marktarget = 0;
+
+  /**
+   * This is the number of bytes to allocate to reach marktarget.
+   */
+  static final protected int CHUNKSIZE = 1024;
+
+  /**
    * This method initializes a new <code>BufferedInputStream</code> that will
    * read from the specified subordinate stream with a default buffer size
    * of 2048 bytes
@@ -183,7 +196,9 @@
    */
   public synchronized void mark(int readlimit)
   {
-    marklimit = readlimit;
+    marktarget = marklimit = readlimit;
+    if (marklimit > CHUNKSIZE)
+       marklimit = CHUNKSIZE;
     markpos = pos;
   }
 
@@ -337,13 +352,16 @@
        pos -= markpos;
        markpos = 0;
       }
-    else if (marklimit >= buf.length)  // BTW, markpos == 0
+    else if (marktarget >= buf.length && marklimit < marktarget)       // BTW, 
markpos == 0
       {
        // Need to grow the buffer now to have room for marklimit bytes.
        // Note that the new buffer is one greater than marklimit.
        // This is so that there will be one byte past marklimit to be read
        // before having to call refill again, thus allowing marklimit to be
        // invalidated.  That way refill doesn't have to check marklimit.
+       marklimit += CHUNKSIZE;
+       if (marklimit >= marktarget)
+         marklimit = marktarget;
        byte[] newbuf = new byte[marklimit + 1];
        System.arraycopy(buf, 0, newbuf, 0, count);
        buf = newbuf;

pgpN46umHbZus.pgp
Description: PGP signature