natFileDescriptorWin32.cc (read): Handle case where count is 0.

	* java/io/natFileDescriptorWin32.cc (read): Handle case where
	count is 0.
	* java/io/natFileDescriptorPosix.cc (read): Handle case where
	count is 0.

From-SVN: r58997

libjava/ChangeLog

 2002-11-10  Tom Tromey  <tromey@redhat.com>
 
+	* java/io/natFileDescriptorWin32.cc (read): Handle case where
+	count is 0.
+	* java/io/natFileDescriptorPosix.cc (read): Handle case where
+	count is 0.
+
 	* java/io/Externalizable.java, java/io/FilePermission.java,
 	java/io/ObjectStreamConstants.java, java/io/Serializable.java,
 	java/io/SerializablePermission.java, java/text/Format.java,

libjava/java/io/natFileDescriptorPosix.cc

@@ -293,6 +293,11 @@ java::io::FileDescriptor::read (jbyteArray buffer, jint offset, jint count)
   jsize bsize = JvGetArrayLength (buffer);
   if (offset < 0 || count < 0 || offset + count > bsize)
     throw new java::lang::ArrayIndexOutOfBoundsException;
+
+  // Must return 0 if an attempt is made to read 0 bytes.
+  if (count == 0)
+    return 0;
+
   jbyte *bytes = elements (buffer) + offset;
   int r = ::read (fd, bytes, count);
   if (r == 0)

libjava/java/io/natFileDescriptorWin32.cc

@@ -305,6 +305,10 @@ java::io::FileDescriptor::read(jbyteArray buffer, jint offset, jint count)
   if (offset < 0 || count < 0 || offset + count > bsize)
     throw new java::lang::ArrayIndexOutOfBoundsException;
 
+  // Must return 0 if an attempt is made to read 0 bytes.
+  if (count == 0)
+    return 0;
+
   jbyte *bytes = elements (buffer) + offset;
 
   DWORD read;