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*
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package org.luaj.vm2.lib;
import java.io.ByteArrayOutputStream;
import java.io.EOFException;
import java.io.IOException;
import org.luaj.vm2.Globals;
import org.luaj.vm2.LuaString;
import org.luaj.vm2.LuaTable;
import org.luaj.vm2.LuaValue;
import org.luaj.vm2.Varargs;
/**
* Abstract base class extending {@link LibFunction} which implements the
* core of the lua standard {@code io} library.
*
* It contains the implementation of the io library support that is common to
* the JSE and JME platforms.
* In practice on of the concrete IOLib subclasses is chosen:
* {@link org.luaj.vm2.lib.jse.JseIoLib} for the JSE platform, and
* {@link org.luaj.vm2.lib.jme.JmeIoLib} for the JME platform.
*
* The JSE implementation conforms almost completely to the C-based lua library,
* while the JME implementation follows closely except in the area of random-access files,
* which are difficult to support properly on JME.
*
* Typically, this library is included as part of a call to either
* {@link JsePlatform#standardGlobals()} or {@link JmePlatform#standardGlobals()}
*
{@code
* Globals globals = JsePlatform.standardGlobals();
* globals.get("io").get("write").call(LuaValue.valueOf("hello, world\n"));
* }
* In this example the platform-specific {@link JseIoLib} library will be loaded, which will include
* the base functionality provided by this class, whereas the {@link JsePlatform} would load the
* {@link JseIoLib}.
*
* To instantiate and use it directly,
* link it into your globals table via {@link LuaValue#load(LuaValue)} using code such as:
*
{@code
* Globals globals = new Globals();
* globals.load(new JseBaseLib());
* globals.load(new PackageLib());
* globals.load(new OsLib());
* globals.get("io").get("write").call(LuaValue.valueOf("hello, world\n"));
* }
*
* 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 JseIoLib
* @see JmeIoLib
* @see http://www.lua.org/manual/5.1/manual.html#5.7
*/
abstract
public class IoLib extends TwoArgFunction {
abstract
protected class File extends LuaValue{
abstract public void write( LuaString string ) throws IOException;
abstract public void flush() throws IOException;
abstract public boolean isstdfile();
abstract public void close() throws IOException;
abstract public boolean isclosed();
// returns new position
abstract public int seek(String option, int bytecount) throws IOException;
abstract public void setvbuf(String mode, int size);
// get length remaining to read
abstract public int remaining() throws IOException;
// peek ahead one character
abstract public int peek() throws IOException, EOFException;
// return char if read, -1 if eof, throw IOException on other exception
abstract public int read() throws IOException, EOFException;
// return number of bytes read if positive, false if eof, throw IOException on other exception
abstract public int read(byte[] bytes, int offset, int length) throws IOException;
// delegate method access to file methods table
public LuaValue get( LuaValue key ) {
return filemethods.get(key);
}
// essentially a userdata instance
public int type() {
return LuaValue.TUSERDATA;
}
public String typename() {
return "userdata";
}
// displays as "file" type
public String tojstring() {
return "file: " + Integer.toHexString(hashCode());
}
}
/** Enumerated value representing stdin */
protected static final int FTYPE_STDIN = 0;
/** Enumerated value representing stdout */
protected static final int FTYPE_STDOUT = 1;
/** Enumerated value representing stderr */
protected static final int FTYPE_STDERR = 2;
/** Enumerated value representing a file type for a named file */
protected static final int FTYPE_NAMED = 3;
/**
* Wrap the standard input.
* @return File
* @throws IOException
*/
abstract protected File wrapStdin() throws IOException;
/**
* Wrap the standard output.
* @return File
* @throws IOException
*/
abstract protected File wrapStdout() throws IOException;
/**
* Wrap the standard error output.
* @return File
* @throws IOException
*/
abstract protected File wrapStderr() throws IOException;
/**
* Open a file in a particular mode.
* @param filename
* @param readMode true if opening in read mode
* @param appendMode true if opening in append mode
* @param updateMode true if opening in update mode
* @param binaryMode true if opening in binary mode
* @return File object if successful
* @throws IOException if could not be opened
*/
abstract protected File openFile( String filename, boolean readMode, boolean appendMode, boolean updateMode, boolean binaryMode ) throws IOException;
/**
* Open a temporary file.
* @return File object if successful
* @throws IOException if could not be opened
*/
abstract protected File tmpFile() throws IOException;
/**
* Start a new process and return a file for input or output
* @param prog the program to execute
* @param mode "r" to read, "w" to write
* @return File to read to or write from
* @throws IOException if an i/o exception occurs
*/
abstract protected File openProgram(String prog, String mode) throws IOException;
private File infile = null;
private File outfile = null;
private File errfile = null;
private static final LuaValue STDIN = valueOf("stdin");
private static final LuaValue STDOUT = valueOf("stdout");
private static final LuaValue STDERR = valueOf("stderr");
private static final LuaValue FILE = valueOf("file");
private static final LuaValue CLOSED_FILE = valueOf("closed file");
private static final int IO_CLOSE = 0;
private static final int IO_FLUSH = 1;
private static final int IO_INPUT = 2;
private static final int IO_LINES = 3;
private static final int IO_OPEN = 4;
private static final int IO_OUTPUT = 5;
private static final int IO_POPEN = 6;
private static final int IO_READ = 7;
private static final int IO_TMPFILE = 8;
private static final int IO_TYPE = 9;
private static final int IO_WRITE = 10;
private static final int FILE_CLOSE = 11;
private static final int FILE_FLUSH = 12;
private static final int FILE_LINES = 13;
private static final int FILE_READ = 14;
private static final int FILE_SEEK = 15;
private static final int FILE_SETVBUF = 16;
private static final int FILE_WRITE = 17;
private static final int IO_INDEX = 18;
private static final int LINES_ITER = 19;
public static final String[] IO_NAMES = {
"close",
"flush",
"input",
"lines",
"open",
"output",
"popen",
"read",
"tmpfile",
"type",
"write",
};
public static final String[] FILE_NAMES = {
"close",
"flush",
"lines",
"read",
"seek",
"setvbuf",
"write",
};
LuaTable filemethods;
protected Globals globals;
public LuaValue call(LuaValue modname, LuaValue env) {
globals = env.checkglobals();
// io lib functions
LuaTable t = new LuaTable();
bind(t, IoLibV.class, IO_NAMES );
// create file methods table
filemethods = new LuaTable();
bind(filemethods, IoLibV.class, FILE_NAMES, FILE_CLOSE );
// set up file metatable
LuaTable mt = new LuaTable();
bind(mt, IoLibV.class, new String[] { "__index" }, IO_INDEX );
t.setmetatable( mt );
// all functions link to library instance
setLibInstance( t );
setLibInstance( filemethods );
setLibInstance( mt );
// return the table
env.set("io", t);
env.get("package").get("loaded").set("io", t);
return t;
}
private void setLibInstance(LuaTable t) {
LuaValue[] k = t.keys();
for ( int i=0, n=k.length; i bool
public Varargs _io_flush() throws IOException {
checkopen(output());
outfile.flush();
return LuaValue.TRUE;
}
// io.tmpfile() -> file
public Varargs _io_tmpfile() throws IOException {
return tmpFile();
}
// io.close([file]) -> void
public Varargs _io_close(LuaValue file) throws IOException {
File f = file.isnil()? output(): checkfile(file);
checkopen(f);
return ioclose(f);
}
// io.input([file]) -> file
public Varargs _io_input(LuaValue file) {
infile = file.isnil()? input():
file.isstring()? ioopenfile(FTYPE_NAMED, file.checkjstring(),"r"):
checkfile(file);
return infile;
}
// io.output(filename) -> file
public Varargs _io_output(LuaValue filename) {
outfile = filename.isnil()? output():
filename.isstring()? ioopenfile(FTYPE_NAMED, filename.checkjstring(),"w"):
checkfile(filename);
return outfile;
}
// io.type(obj) -> "file" | "closed file" | nil
public Varargs _io_type(LuaValue obj) {
File f = optfile(obj);
return f!=null?
f.isclosed()? CLOSED_FILE: FILE:
NIL;
}
// io.popen(prog, [mode]) -> file
public Varargs _io_popen(String prog, String mode) throws IOException {
return openProgram(prog, mode);
}
// io.open(filename, [mode]) -> file | nil,err
public Varargs _io_open(String filename, String mode) throws IOException {
return rawopenfile(FTYPE_NAMED, filename, mode);
}
// io.lines(filename) -> iterator
public Varargs _io_lines(String filename) {
infile = filename==null? input(): ioopenfile(FTYPE_NAMED, filename,"r");
checkopen(infile);
return lines(infile);
}
// io.read(...) -> (...)
public Varargs _io_read(Varargs args) throws IOException {
checkopen(input());
return ioread(infile,args);
}
// io.write(...) -> void
public Varargs _io_write(Varargs args) throws IOException {
checkopen(output());
return iowrite(outfile,args);
}
// file:close() -> void
public Varargs _file_close(LuaValue file) throws IOException {
return ioclose(checkfile(file));
}
// file:flush() -> void
public Varargs _file_flush(LuaValue file) throws IOException {
checkfile(file).flush();
return LuaValue.TRUE;
}
// file:setvbuf(mode,[size]) -> void
public Varargs _file_setvbuf(LuaValue file, String mode, int size) {
checkfile(file).setvbuf(mode,size);
return LuaValue.TRUE;
}
// file:lines() -> iterator
public Varargs _file_lines(LuaValue file) {
return lines(checkfile(file));
}
// file:read(...) -> (...)
public Varargs _file_read(LuaValue file, Varargs subargs) throws IOException {
return ioread(checkfile(file),subargs);
}
// file:seek([whence][,offset]) -> pos | nil,error
public Varargs _file_seek(LuaValue file, String whence, int offset) throws IOException {
return valueOf( checkfile(file).seek(whence,offset) );
}
// file:write(...) -> void
public Varargs _file_write(LuaValue file, Varargs subargs) throws IOException {
return iowrite(checkfile(file),subargs);
}
// __index, returns a field
public Varargs _io_index(LuaValue v) {
return v.equals(STDOUT)?output():
v.equals(STDIN)? input():
v.equals(STDERR)? errput(): NIL;
}
// lines iterator(s,var) -> var'
public Varargs _lines_iter(LuaValue file) throws IOException {
return freadline(checkfile(file));
}
private File output() {
return outfile!=null? outfile: (outfile=ioopenfile(FTYPE_STDOUT,"-","w"));
}
private File errput() {
return errfile!=null? errfile: (errfile=ioopenfile(FTYPE_STDERR,"-","w"));
}
private File ioopenfile(int filetype, String filename, String mode) {
try {
return rawopenfile(filetype, filename, mode);
} catch ( Exception e ) {
error("io error: "+e.getMessage());
return null;
}
}
private static Varargs ioclose(File f) throws IOException {
if ( f.isstdfile() )
return errorresult("cannot close standard file");
else {
f.close();
return successresult();
}
}
private static Varargs successresult() {
return LuaValue.TRUE;
}
private static Varargs errorresult(Exception ioe) {
String s = ioe.getMessage();
return errorresult("io error: "+(s!=null? s: ioe.toString()));
}
private static Varargs errorresult(String errortext) {
return varargsOf(NIL, valueOf(errortext));
}
private Varargs lines(final File f) {
try {
return new IoLibV(f,"lnext",LINES_ITER,this);
} catch ( Exception e ) {
return error("lines: "+e);
}
}
private static Varargs iowrite(File f, Varargs args) throws IOException {
for ( int i=1, n=args.narg(); i<=n; i++ )
f.write( args.checkstring(i) );
return f;
}
private Varargs ioread(File f, Varargs args) throws IOException {
int i,n=args.narg();
LuaValue[] v = new LuaValue[n];
LuaValue ai,vi;
LuaString fmt;
for ( i=0; i 0;
boolean isbinary = mode.endsWith("b");
return openFile( filename, isreadmode, isappend, isupdate, isbinary );
}
// ------------- file reading utilitied ------------------
public static LuaValue freadbytes(File f, int count) throws IOException {
byte[] b = new byte[count];
int r;
if ( ( r = f.read(b,0,b.length) ) < 0 )
return NIL;
return LuaString.valueOf(b, 0, r);
}
public static LuaValue freaduntil(File f,boolean lineonly) throws IOException {
ByteArrayOutputStream baos = new ByteArrayOutputStream();
int c;
try {
if ( lineonly ) {
loop: while ( (c = f.read()) > 0 ) {
switch ( c ) {
case '\r': break;
case '\n': break loop;
default: baos.write(c); break;
}
}
} else {
while ( (c = f.read()) > 0 )
baos.write(c);
}
} catch ( EOFException e ) {
c = -1;
}
return ( c < 0 && baos.size() == 0 )?
(LuaValue) NIL:
(LuaValue) LuaString.valueOf(baos.toByteArray());
}
public static LuaValue freadline(File f) throws IOException {
return freaduntil(f,true);
}
public static LuaValue freadall(File f) throws IOException {
int n = f.remaining();
if ( n >= 0 ) {
return freadbytes(f, n);
} else {
return freaduntil(f,false);
}
}
public static LuaValue freadnumber(File f) throws IOException {
ByteArrayOutputStream baos = new ByteArrayOutputStream();
freadchars(f," \t\r\n",null);
freadchars(f,"-+",baos);
//freadchars(f,"0",baos);
//freadchars(f,"xX",baos);
freadchars(f,"0123456789",baos);
freadchars(f,".",baos);
freadchars(f,"0123456789",baos);
//freadchars(f,"eEfFgG",baos);
// freadchars(f,"+-",baos);
//freadchars(f,"0123456789",baos);
String s = baos.toString();
return s.length()>0? valueOf( Double.parseDouble(s) ): NIL;
}
private static void freadchars(File f, String chars, ByteArrayOutputStream baos) throws IOException {
int c;
while ( true ) {
c = f.peek();
if ( chars.indexOf(c) < 0 ) {
return;
}
f.read();
if ( baos != null )
baos.write( c );
}
}
}