/*******************************************************************************
* Copyright (c) 2009 Luaj.org. All rights reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
******************************************************************************/
package org.luaj.vm2.lib.jse;
import java.io.BufferedInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.RandomAccessFile;
import org.luaj.vm2.LuaError;
import org.luaj.vm2.LuaString;
import org.luaj.vm2.LuaValue;
import org.luaj.vm2.lib.BaseLib;
import org.luaj.vm2.lib.IoLib;
import org.luaj.vm2.lib.LibFunction;
/**
* Subclass of {@link IoLib} and therefore {@link LibFunction} which implements the lua standard {@code io}
* library for the JSE platform.
* <p>
* It uses RandomAccessFile to implement seek on files.
* <p>
* Typically, this library is included as part of a call to
* {@link JsePlatform#standardGlobals()}
* <p>
* To instantiate and use it directly,
* link it into your globals table via {@link LuaValue#load(LuaValue)} using code such as:
* <pre> {@code
* LuaTable _G = new LuaTable();
* LuaThread.setGlobals(_G);
* _G.load(new JseBaseLib());
* _G.load(new PackageLib());
* _G.load(new JseIoLib());
* _G.get("io").get("write").call(LuaValue.valueOf("hello, world\n"));
* } </pre>
* Doing so will ensure the library is properly initialized
* and loaded into the globals table.
* <p>
* This has been implemented to match as closely as possible the behavior in the corresponding library in C.
* @see LibFunction
* @see JsePlatform
* @see JmePlatform
* @see IoLib
* @see JmeIoLib
* @see <a href="http://www.lua.org/manual/5.1/manual.html#5.7">http://www.lua.org/manual/5.1/manual.html#5.7</a>
*/
public class JseIoLib extends IoLib {
public JseIoLib() {
super();
}
protected File wrapStdin() throws IOException {
return new FileImpl(BaseLib.instance.STDIN);
}
protected File wrapStdout() throws IOException {
return new FileImpl(BaseLib.instance.STDOUT);
}
protected File openFile( String filename, boolean readMode, boolean appendMode, boolean updateMode, boolean binaryMode ) throws IOException {
RandomAccessFile f = new RandomAccessFile(filename,readMode? "r": "rw");
if ( appendMode ) {
f.seek(f.length());
} else {
if ( ! readMode )
f.setLength(0);
}
return new FileImpl( f );
}
protected File openProgram(String prog, String mode) throws IOException {
final Process p = Runtime.getRuntime().exec(prog);
return "w".equals(mode)?
new FileImpl( p.getOutputStream() ):
new FileImpl( p.getInputStream() );
}
protected File tmpFile() throws IOException {
java.io.File f = java.io.File.createTempFile(".luaj","bin");
f.deleteOnExit();
return new FileImpl( new RandomAccessFile(f,"rw") );
}
private static void notimplemented() {
throw new LuaError("not implemented");
}
private final class FileImpl extends File {
private final RandomAccessFile file;
private final InputStream is;
private final OutputStream os;
private boolean closed = false;
private boolean nobuffer = false;
private FileImpl( RandomAccessFile file, InputStream is, OutputStream os ) {
this.file = file;
this.is = is!=null? is.markSupported()? is: new BufferedInputStream(is): null;
this.os = os;
}
private FileImpl( RandomAccessFile f ) {
this( f, null, null );
}
private FileImpl( InputStream i ) {
this( null, i, null );
}
private FileImpl( OutputStream o ) {
this( null, null, o );
}
public String tojstring() {
return "file ("+this.hashCode()+")";
}
public boolean isstdfile() {
return file == null;
}
public void close() throws IOException {
closed = true;
if ( file != null ) {
file.close();
}
}
public void flush() throws IOException {
if ( os != null )
os.flush();
}
public void write(LuaString s) throws IOException {
if ( os != null )
os.write( s.m_bytes, s.m_offset, s.m_length );
else if ( file != null )
file.write( s.m_bytes, s.m_offset, s.m_length );
else
notimplemented();
if ( nobuffer )
flush();
}
public boolean isclosed() {
return closed;
}
public int seek(String option, int pos) throws IOException {
if ( file != null ) {
if ( "set".equals(option) ) {
file.seek(pos);
} else if ( "end".equals(option) ) {
file.seek(file.length()+pos);
} else {
file.seek(file.getFilePointer()+pos);
}
return (int) file.getFilePointer();
}
notimplemented();
return 0;
}
public void setvbuf(String mode, int size) {
nobuffer = "no".equals(mode);
}
// get length remaining to read
public int remaining() throws IOException {
return file!=null? (int) (file.length()-file.getFilePointer()): -1;
}
// peek ahead one character
public int peek() throws IOException {
if ( is != null ) {
is.mark(1);
int c = is.read();
is.reset();
return c;
} else if ( file != null ) {
long fp = file.getFilePointer();
int c = file.read();
file.seek(fp);
return c;
}
notimplemented();
return 0;
}
// return char if read, -1 if eof, throw IOException on other exception
public int read() throws IOException {
if ( is != null )
return is.read();
else if ( file != null ) {
return file.read();
}
notimplemented();
return 0;
}
// return number of bytes read if positive, -1 if eof, throws IOException
public int read(byte[] bytes, int offset, int length) throws IOException {
if (file!=null) {
return file.read(bytes, offset, length);
} else if (is!=null) {
return is.read(bytes, offset, length);
} else {
notimplemented();
}
return length;
}
}
}