licensing update to APSL 2.0

[nestedvm.git] / src / org / ibex / nestedvm / util / Seekable.java

diff --git a/src/org/ibex/nestedvm/util/Seekable.java b/src/org/ibex/nestedvm/util/Seekable.java
index 85a48cc..bc21a55 100644 (file)
--- a/src/org/ibex/nestedvm/util/Seekable.java
+++ b/src/org/ibex/nestedvm/util/Seekable.java
@@ -1,16 +1,38 @@
+// Copyright 2000-2005 the Contributors, as shown in the revision logs.
+// Licensed under the Apache Public Source License 2.0 ("the License").
+// You may not use this file except in compliance with the License.
+
 package org.ibex.nestedvm.util;
 
 import java.io.*;
 
-public interface Seekable { 
-    public int read(byte[] buf, int offset, int length) throws IOException;
-    public int write(byte[] buf, int offset, int length) throws IOException;
-    public int length() throws IOException;
-    public void seek(int pos) throws IOException;
-    public void close() throws IOException;
-    public int pos() throws IOException;
+public abstract class Seekable { 
+    public abstract int read(byte[] buf, int offset, int length) throws IOException;
+    public abstract int write(byte[] buf, int offset, int length) throws IOException;
+    public abstract int length() throws IOException;
+    public abstract void seek(int pos) throws IOException;
+    public abstract void close() throws IOException;
+    public abstract int pos() throws IOException;
+    
+    public int read() throws IOException {
+        byte[] buf = new byte[1];
+        int n = read(buf,0,1);
+        return n == -1 ? -1 : buf[0]&0xff;
+    }
+    
+    public int tryReadFully(byte[] buf, int off, int len) throws IOException {
+        int total = 0;
+        while(len > 0) {
+                int n = read(buf,off,len);
+                if(n == -1) break;
+                off += n;
+                len -= n;
+            total += n;
+        }
+        return total == 0 ? -1 : total;
+    }
     
-    public class ByteArray implements Seekable {
+    public static class ByteArray extends Seekable {
         protected byte[] data;
         protected int pos;
         private final boolean writable;
@@ -28,7 +50,7 @@ public interface Seekable {
             pos += len;
             return len;
         }
-        
+                
         public int write(byte[] buf, int off, int len) throws IOException {
             if(!writable) throw new IOException("read-only data");
             len = Math.min(len,data.length-pos);
@@ -44,19 +66,17 @@ public interface Seekable {
         public void close() { /*noop*/ }
     }
     
-    public class File implements Seekable {
+    public static class File extends Seekable {
         private final RandomAccessFile raf;
         
         public File(String fileName) throws IOException { this(fileName,false); }
-        public File(String fileName, boolean writable) throws IOException { this(new java.io.File(fileName),writable); }    
+        public File(String fileName, boolean writable) throws IOException { this(new java.io.File(fileName),writable,false); }    
         
-        public File(java.io.File file, boolean writable) throws IOException {
-            raf = new RandomAccessFile(file,writable ? "rw" : "r");
+        public File(java.io.File file, boolean writable, boolean truncate) throws IOException {
+            String mode = writable ? "rw" : "r";
+            raf = truncate ? Platform.truncatedRandomAccessFile(file,mode) : new RandomAccessFile(file,mode);
         }
         
-        // NOTE: RandomAccessFile.setLength() is a Java2 function
-        public void setLength(int n) throws IOException { raf.setLength(n); }
-        
         public int read(byte[] buf, int offset, int length) throws IOException { return raf.read(buf,offset,length); }
         public int write(byte[] buf, int offset, int length) throws IOException { raf.write(buf,offset,length); return length; }
         public void seek(int pos) throws IOException{ raf.seek(pos); }
@@ -65,7 +85,7 @@ public interface Seekable {
         public void close() throws IOException { raf.close(); }
     }
     
-    public class InputStream implements Seekable {
+    public static class InputStream extends Seekable {
         private byte[] buffer = new byte[4096];
         private int bytesRead = 0;
         private boolean eof = false;