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Luaj 3.0.1 for the jme platform
/*******************************************************************************
* 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;
import java.io.DataInputStream;
import java.io.IOException;
import java.io.InputStream;
import org.luaj.vm2.compiler.DumpState;
/**
* Class to undump compiled lua bytecode into a {@link Prototype} instances.
*
* The {@link LoadState} class implements {@link Globals#Undumper}
* which is used to undump a string of bytes that represent a lua binary file
* using either the C-based lua compiler, or luaj's {@link DumpState#dump} function.
*
* The canonical method to load and execute code is done
* indirectly using the Globals:
*
{@code
* Globals globals = JsePlatform.standardGlobals();
* LuaValue chunk = globasl.load("print('hello, world')", "main.lua");
* chunk.call();
* }
* This should work regardless of which {@link Globals.Compiler}
* has been installed.
*
* By default, when using {@link JsePlatform} or {@JmePlatform}
* to construct globals, the {@link LoadState} is installed
* as the default {@link Globals#undumper}.
*
*
* A lua binary file is created via {@link DumpState#dump}:
*
{@code
* Globals globals = JsePlatform.standardGlobals();
* Prototype p = globals.compilePrototype(new StringReader("print('hello, world')"), "main.lua");
* ByteArrayOutputStream o = new ByteArrayOutputStream();
* DumpState.dump(p, o, false);
* byte[] lua_binary_file_bytes = o.toByteArray();
* }
*
* The {@link LoadState} may be used directly to undump these bytes:
* {@code
* Prototypep = LoadState.instance.undump(new ByteArrayInputStream(lua_binary_file_bytes), "main.lua");
* LuaClosure c = new LuaClosure(p, globals);
* c.call();
* }
*
*
* More commonly, the {@link Globals#undumper} may be used to undump them:
* {@code
* Prototype p = globals.loadPrototype(new ByteArrayInputStream(lua_binary_file_bytes), "main.lua", "b");
* LuaClosure c = new LuaClosure(p, globals);
* c.call();
* }
*
* @see LuaCompiler
* @see LuaClosure
* @see LuaFunction
* @see LoadState#compiler
* @see LoadState#load(InputStream, String, LuaValue)
* @see LuaC
* @see LuaJC
*/
public class LoadState implements Globals.Undumper {
/** Shared instance of Globals.Undumper to use loading prototypes from binary lua files */
public static final Globals.Undumper instance = new LoadState();
/** format corresponding to non-number-patched lua, all numbers are floats or doubles */
public static final int NUMBER_FORMAT_FLOATS_OR_DOUBLES = 0;
/** format corresponding to non-number-patched lua, all numbers are ints */
public static final int NUMBER_FORMAT_INTS_ONLY = 1;
/** format corresponding to number-patched lua, all numbers are 32-bit (4 byte) ints */
public static final int NUMBER_FORMAT_NUM_PATCH_INT32 = 4;
// type constants
public static final int LUA_TINT = (-2);
public static final int LUA_TNONE = (-1);
public static final int LUA_TNIL = 0;
public static final int LUA_TBOOLEAN = 1;
public static final int LUA_TLIGHTUSERDATA = 2;
public static final int LUA_TNUMBER = 3;
public static final int LUA_TSTRING = 4;
public static final int LUA_TTABLE = 5;
public static final int LUA_TFUNCTION = 6;
public static final int LUA_TUSERDATA = 7;
public static final int LUA_TTHREAD = 8;
public static final int LUA_TVALUE = 9;
/** The character encoding to use for file encoding. Null means the default encoding */
public static String encoding = null;
/** Signature byte indicating the file is a compiled binary chunk */
public static final byte[] LUA_SIGNATURE = { '\033', 'L', 'u', 'a' };
/** Data to catch conversion errors */
public static final byte[] LUAC_TAIL = { (byte) 0x19, (byte) 0x93, '\r', '\n', (byte) 0x1a, '\n', };
/** Name for compiled chunks */
public static final String SOURCE_BINARY_STRING = "binary string";
/** for header of binary files -- this is Lua 5.2 */
public static final int LUAC_VERSION = 0x52;
/** for header of binary files -- this is the official format */
public static final int LUAC_FORMAT = 0;
/** size of header of binary files */
public static final int LUAC_HEADERSIZE = 12;
// values read from the header
private int luacVersion;
private int luacFormat;
private boolean luacLittleEndian;
private int luacSizeofInt;
private int luacSizeofSizeT;
private int luacSizeofInstruction;
private int luacSizeofLuaNumber;
private int luacNumberFormat;
/** input stream from which we are loading */
public final DataInputStream is;
/** Name of what is being loaded? */
String name;
private static final LuaValue[] NOVALUES = {};
private static final Prototype[] NOPROTOS = {};
private static final LocVars[] NOLOCVARS = {};
private static final LuaString[] NOSTRVALUES = {};
private static final Upvaldesc[] NOUPVALDESCS = {};
private static final int[] NOINTS = {};
/** Read buffer */
private byte[] buf = new byte[512];
/** Install this class as the standard Globals.Undumper for the supplied Globals */
public static void install(Globals globals) {
globals.undumper = instance;
}
/** Load a 4-byte int value from the input stream
* @return the int value laoded.
**/
int loadInt() throws IOException {
is.readFully(buf,0,4);
return luacLittleEndian?
(buf[3] << 24) | ((0xff & buf[2]) << 16) | ((0xff & buf[1]) << 8) | (0xff & buf[0]):
(buf[0] << 24) | ((0xff & buf[1]) << 16) | ((0xff & buf[2]) << 8) | (0xff & buf[3]);
}
/** Load an array of int values from the input stream
* @return the array of int values laoded.
**/
int[] loadIntArray() throws IOException {
int n = loadInt();
if ( n == 0 )
return NOINTS;
// read all data at once
int m = n << 2;
if ( buf.length < m )
buf = new byte[m];
is.readFully(buf,0,m);
int[] array = new int[n];
for ( int i=0, j=0; i> 52) & 0x7ffL) - 1023;
if ( e >= 0 && e < 31 ) {
long f = bits & 0xFFFFFFFFFFFFFL;
int shift = 52 - e;
long intPrecMask = ( 1L << shift ) - 1;
if ( ( f & intPrecMask ) == 0 ) {
int intValue = (int)( f >> shift ) | ( 1 << e );
return LuaInteger.valueOf( ( ( bits >> 63 ) != 0 ) ? -intValue : intValue );
}
}
return LuaValue.valueOf( Double.longBitsToDouble(bits) );
}
/**
* Load a number from a binary chunk
* @return the {@link LuaValue} loaded
* @throws IOException if an i/o exception occurs
*/
LuaValue loadNumber() throws IOException {
if ( luacNumberFormat == NUMBER_FORMAT_INTS_ONLY ) {
return LuaInteger.valueOf( loadInt() );
} else {
return longBitsToLuaNumber( loadInt64() );
}
}
/**
* Load a list of constants from a binary chunk
* @param f the function prototype
* @throws IOException if an i/o exception occurs
*/
void loadConstants(Prototype f) throws IOException {
int n = loadInt();
LuaValue[] values = n>0? new LuaValue[n]: NOVALUES;
for ( int i=0; i0? new Prototype[n]: NOPROTOS;
for ( int i=0; i0? new Upvaldesc[n]: NOUPVALDESCS;
for (int i=0; i0? new LocVars[n]: NOLOCVARS;
for ( int i=0; i