/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
/*
*******************************************************************************
* Copyright (C) 2003-2004, International Business Machines Corporation and *
* others. All Rights Reserved. *
*******************************************************************************
*/
//
// CHANGELOG
// 2005-05-19 Edward Wang
// - copy this file from icu4jsrc_3_2/src/com/ibm/icu/text/Punycode.java
// - move from package com.ibm.icu.text to package sun.net.idn
// - use ParseException instead of StringPrepParseException
// 2007-08-14 Martin Buchholz
// - remove redundant casts
//
package sun.net.idn;
import java.text.ParseException;
import sun.text.normalizer.UCharacter;
import sun.text.normalizer.UTF16;
/**
* Ported code from ICU punycode.c
* @author ram
*/
/* Package Private class */
public final class Punycode {
/* Punycode parameters for Bootstring */
private static final int BASE = 36;
private static final int TMIN = 1;
private static final int TMAX = 26;
private static final int SKEW = 38;
private static final int DAMP = 700;
private static final int INITIAL_BIAS = 72;
private static final int INITIAL_N = 0x80;
/* "Basic" Unicode/ASCII code points */
private static final int HYPHEN = 0x2d;
private static final int DELIMITER = HYPHEN;
private static final int ZERO = 0x30;
private static final int NINE = 0x39;
private static final int SMALL_A = 0x61;
private static final int SMALL_Z = 0x7a;
private static final int CAPITAL_A = 0x41;
private static final int CAPITAL_Z = 0x5a;
// TODO: eliminate the 256 limitation
private static final int MAX_CP_COUNT = 256;
private static final int UINT_MAGIC = 0x80000000;
private static final long ULONG_MAGIC = 0x8000000000000000L;
private static int adaptBias(int delta, int length, boolean firstTime){
if(firstTime){
delta /=DAMP;
}else{
delta /= 2;
}
delta += delta/length;
int count=0;
for(; delta>((BASE-TMIN)*TMAX)/2; count+=BASE) {
delta/=(BASE-TMIN);
}
return count+(((BASE-TMIN+1)*delta)/(delta+SKEW));
}
/**
* basicToDigit[] contains the numeric value of a basic code
* point (for use in representing integers) in the range 0 to
* BASE-1, or -1 if b is does not represent a value.
*/
static final int[] basicToDigit= new int[]{
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
26, 27, 28, 29, 30, 31, 32, 33, 34, 35, -1, -1, -1, -1, -1, -1,
-1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14,
15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, -1,
-1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14,
15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1
};
private static char asciiCaseMap(char b, boolean uppercase) {
if(uppercase) {
if(SMALL_A<=b && b<=SMALL_Z) {
b-=(SMALL_A-CAPITAL_A);
}
} else {
if(CAPITAL_A<=b && b<=CAPITAL_Z) {
b+=(SMALL_A-CAPITAL_A);
}
}
return b;
}
/**
* digitToBasic() returns the basic code point whose value
* (when used for representing integers) is d, which must be in the
* range 0 to BASE-1. The lowercase form is used unless the uppercase flag is
* nonzero, in which case the uppercase form is used.
*/
private static char digitToBasic(int digit, boolean uppercase) {
/* 0..25 map to ASCII a..z or A..Z */
/* 26..35 map to ASCII 0..9 */
if(digit<26) {
if(uppercase) {
return (char)(CAPITAL_A+digit);
} else {
return (char)(SMALL_A+digit);
}
} else {
return (char)((ZERO-26)+digit);
}
}
/**
* Converts Unicode to Punycode.
* The input string must not contain single, unpaired surrogates.
* The output will be represented as an array of ASCII code points.
*
* @param src
* @param caseFlags
* @return
* @throws ParseException
*/
public static StringBuffer encode(StringBuffer src, boolean[] caseFlags) throws ParseException{
int[] cpBuffer = new int[MAX_CP_COUNT];
int n, delta, handledCPCount, basicLength, destLength, bias, j, m, q, k, t, srcCPCount;
char c, c2;
int srcLength = src.length();
int destCapacity = MAX_CP_COUNT;
char[] dest = new char[destCapacity];
StringBuffer result = new StringBuffer();
/*
* Handle the basic code points and
* convert extended ones to UTF-32 in cpBuffer (caseFlag in sign bit):
*/
srcCPCount=destLength=0;
for(j=0; j<srcLength; ++j) {
if(srcCPCount==MAX_CP_COUNT) {
/* too many input code points */
throw new IndexOutOfBoundsException();
}
c=src.charAt(j);
if(isBasic(c)) {
if(destLength<destCapacity) {
cpBuffer[srcCPCount++]=0;
dest[destLength]=
caseFlags!=null ?
asciiCaseMap(c, caseFlags[j]) :
c;
}
++destLength;
} else {
n=((caseFlags!=null && caseFlags[j])? 1 : 0)<<31L;
if(!UTF16.isSurrogate(c)) {
n|=c;
} else if(UTF16.isLeadSurrogate(c) && (j+1)<srcLength && UTF16.isTrailSurrogate(c2=src.charAt(j+1))) {
++j;
n|=UCharacter.getCodePoint(c, c2);
} else {
/* error: unmatched surrogate */
throw new ParseException("Illegal char found", -1);
}
cpBuffer[srcCPCount++]=n;
}
}
/* Finish the basic string - if it is not empty - with a delimiter. */
basicLength=destLength;
if(basicLength>0) {
if(destLength<destCapacity) {
dest[destLength]=DELIMITER;
}
++destLength;
}
/*
* handledCPCount is the number of code points that have been handled
* basicLength is the number of basic code points
* destLength is the number of chars that have been output
*/
/* Initialize the state: */
n=INITIAL_N;
delta=0;
bias=INITIAL_BIAS;
/* Main encoding loop: */
for(handledCPCount=basicLength; handledCPCount<srcCPCount; /* no op */) {
/*
* All non-basic code points < n have been handled already.
* Find the next larger one:
*/
for(m=0x7fffffff, j=0; j<srcCPCount; ++j) {
q=cpBuffer[j]&0x7fffffff; /* remove case flag from the sign bit */
if(n<=q && q<m) {
m=q;
}
}
/*
* Increase delta enough to advance the decoder's
* <n,i> state to <m,0>, but guard against overflow:
*/
if(m-n>(0x7fffffff-MAX_CP_COUNT-delta)/(handledCPCount+1)) {
throw new RuntimeException("Internal program error");
}
delta+=(m-n)*(handledCPCount+1);
n=m;
/* Encode a sequence of same code points n */
for(j=0; j<srcCPCount; ++j) {
q=cpBuffer[j]&0x7fffffff; /* remove case flag from the sign bit */
if(q<n) {
++delta;
} else if(q==n) {
/* Represent delta as a generalized variable-length integer: */
for(q=delta, k=BASE; /* no condition */; k+=BASE) {
/** RAM: comment out the old code for conformance with draft-ietf-idn-punycode-03.txt
t=k-bias;
if(t<TMIN) {
t=TMIN;
} else if(t>TMAX) {
t=TMAX;
}
*/
t=k-bias;
if(t<TMIN) {
t=TMIN;
} else if(k>=(bias+TMAX)) {
t=TMAX;
}
if(q<t) {
break;
}
if(destLength<destCapacity) {
dest[destLength++]=digitToBasic(t+(q-t)%(BASE-t), false);
}
q=(q-t)/(BASE-t);
}
if(destLength<destCapacity) {
dest[destLength++]=digitToBasic(q, (cpBuffer[j]<0));
}
bias=adaptBias(delta, handledCPCount+1,(handledCPCount==basicLength));
delta=0;
++handledCPCount;
}
}
++delta;
++n;
}
return result.append(dest, 0, destLength);
}
private static boolean isBasic(int ch){
return (ch < INITIAL_N);
}
private static boolean isBasicUpperCase(int ch){
return( CAPITAL_A <= ch && ch <= CAPITAL_Z);
}
private static boolean isSurrogate(int ch){
return (((ch)&0xfffff800)==0xd800);
}
/**
* Converts Punycode to Unicode.
* The Unicode string will be at most as long as the Punycode string.
*
* @param src
* @param caseFlags
* @return
* @throws ParseException
*/
public static StringBuffer decode(StringBuffer src, boolean[] caseFlags)
throws ParseException{
int srcLength = src.length();
StringBuffer result = new StringBuffer();
int n, destLength, i, bias, basicLength, j, in, oldi, w, k, digit, t,
destCPCount, firstSupplementaryIndex, cpLength;
char b;
int destCapacity = MAX_CP_COUNT;
char[] dest = new char[destCapacity];
/*
* Handle the basic code points:
* Let basicLength be the number of input code points
* before the last delimiter, or 0 if there is none,
* then copy the first basicLength code points to the output.
*
* The two following loops iterate backward.
*/
for(j=srcLength; j>0;) {
if(src.charAt(--j)==DELIMITER) {
break;
}
}
destLength=basicLength=destCPCount=j;
while(j>0) {
b=src.charAt(--j);
if(!isBasic(b)) {
throw new ParseException("Illegal char found", -1);
}
if(j<destCapacity) {
dest[j]= b;
if(caseFlags!=null) {
caseFlags[j]=isBasicUpperCase(b);
}
}
}
/* Initialize the state: */
n=INITIAL_N;
i=0;
bias=INITIAL_BIAS;
firstSupplementaryIndex=1000000000;
/*
* Main decoding loop:
* Start just after the last delimiter if any
* basic code points were copied; start at the beginning otherwise.
*/
for(in=basicLength>0 ? basicLength+1 : 0; in<srcLength; /* no op */) {
/*
* in is the index of the next character to be consumed, and
* destCPCount is the number of code points in the output array.
*
* Decode a generalized variable-length integer into delta,
* which gets added to i. The overflow checking is easier
* if we increase i as we go, then subtract off its starting
* value at the end to obtain delta.
*/
for(oldi=i, w=1, k=BASE; /* no condition */; k+=BASE) {
if(in>=srcLength) {
throw new ParseException("Illegal char found", -1);
}
digit=basicToDigit[(byte)src.charAt(in++)];
if(digit<0) {
throw new ParseException("Invalid char found", -1);
}
if(digit>(0x7fffffff-i)/w) {
/* integer overflow */
throw new ParseException("Illegal char found", -1);
}
i+=digit*w;
t=k-bias;
if(t<TMIN) {
t=TMIN;
} else if(k>=(bias+TMAX)) {
t=TMAX;
}
if(digit<t) {
break;
}
if(w>0x7fffffff/(BASE-t)) {
/* integer overflow */
throw new ParseException("Illegal char found", -1);
}
w*=BASE-t;
}
/*
* Modification from sample code:
* Increments destCPCount here,
* where needed instead of in for() loop tail.
*/
++destCPCount;
bias=adaptBias(i-oldi, destCPCount, (oldi==0));
/*
* i was supposed to wrap around from (incremented) destCPCount to 0,
* incrementing n each time, so we'll fix that now:
*/
if(i/destCPCount>(0x7fffffff-n)) {
/* integer overflow */
throw new ParseException("Illegal char found", -1);
}
n+=i/destCPCount;
i%=destCPCount;
/* not needed for Punycode: */
/* if (decode_digit(n) <= BASE) return punycode_invalid_input; */
if(n>0x10ffff || isSurrogate(n)) {
/* Unicode code point overflow */
throw new ParseException("Illegal char found", -1);
}
/* Insert n at position i of the output: */
cpLength=UTF16.getCharCount(n);
if((destLength+cpLength)<destCapacity) {
int codeUnitIndex;
/*
* Handle indexes when supplementary code points are present.
*
* In almost all cases, there will be only BMP code points before i
* and even in the entire string.
* This is handled with the same efficiency as with UTF-32.
*
* Only the rare cases with supplementary code points are handled
* more slowly - but not too bad since this is an insertion anyway.
*/
if(i<=firstSupplementaryIndex) {
codeUnitIndex=i;
if(cpLength>1) {
firstSupplementaryIndex=codeUnitIndex;
} else {
++firstSupplementaryIndex;
}
} else {
codeUnitIndex=firstSupplementaryIndex;
codeUnitIndex=UTF16.moveCodePointOffset(dest, 0, destLength, codeUnitIndex, i-codeUnitIndex);
}
/* use the UChar index codeUnitIndex instead of the code point index i */
if(codeUnitIndex<destLength) {
System.arraycopy(dest, codeUnitIndex,
dest, codeUnitIndex+cpLength,
(destLength-codeUnitIndex));
if(caseFlags!=null) {
System.arraycopy(caseFlags, codeUnitIndex,
caseFlags, codeUnitIndex+cpLength,
destLength-codeUnitIndex);
}
}
if(cpLength==1) {
/* BMP, insert one code unit */
dest[codeUnitIndex]=(char)n;
} else {
/* supplementary character, insert two code units */
dest[codeUnitIndex]=UTF16.getLeadSurrogate(n);
dest[codeUnitIndex+1]=UTF16.getTrailSurrogate(n);
}
if(caseFlags!=null) {
/* Case of last character determines uppercase flag: */
caseFlags[codeUnitIndex]=isBasicUpperCase(src.charAt(in-1));
if(cpLength==2) {
caseFlags[codeUnitIndex+1]=false;
}
}
}
destLength+=cpLength;
++i;
}
result.append(dest, 0, destLength);
return result;
}
}