501 lines
15 KiB
Java

/*
* Copyright (c) 2005, 2020, Oracle and/or its affiliates. All rights reserved.
* 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 jdk_internal.icu.impl;
import java.text.ParseException;
import jdk_internal.icu.lang.UCharacter;
import jdk_internal.icu.text.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 ParseException("Too many input code points", -1);
}
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;
}
}