gecko/intl/unicharutil/util/nsBidiUtils.cpp
2010-07-04 15:42:04 +03:00

194 lines
6.9 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
*
* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is mozilla.org code.
*
* The Initial Developer of the Original Code is
* IBM Corporation.
* Portions created by the Initial Developer are Copyright (C) 2000
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Maha Abou El Rous <mahar@eg.ibm.com>
* Lina Kemmel <lkemmel@il.ibm.com>
* Simon Montagu <smontagu@netscape.com>
* Roozbeh Pournader <roozbeh@sharif.edu>
* Ehsan Akhgari <ehsan.akhgari@gmail.com>
*
* Alternatively, the contents of this file may be used under the terms of
* either of the GNU General Public License Version 2 or later (the "GPL"),
* or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#include "nsBidiUtils.h"
#include "bidicattable.h"
#include "nsCharTraits.h"
static nsCharType ebc2ucd[15] = {
eCharType_OtherNeutral, /* Placeholder -- there will never be a 0 index value */
eCharType_LeftToRight,
eCharType_RightToLeft,
eCharType_RightToLeftArabic,
eCharType_ArabicNumber,
eCharType_EuropeanNumber,
eCharType_EuropeanNumberSeparator,
eCharType_EuropeanNumberTerminator,
eCharType_CommonNumberSeparator,
eCharType_OtherNeutral,
eCharType_DirNonSpacingMark,
eCharType_BoundaryNeutral,
eCharType_BlockSeparator,
eCharType_SegmentSeparator,
eCharType_WhiteSpaceNeutral
};
static nsCharType cc2ucd[5] = {
eCharType_LeftToRightEmbedding,
eCharType_RightToLeftEmbedding,
eCharType_PopDirectionalFormat,
eCharType_LeftToRightOverride,
eCharType_RightToLeftOverride
};
#define ARABIC_TO_HINDI_DIGIT_INCREMENT (START_HINDI_DIGITS - START_ARABIC_DIGITS)
#define PERSIAN_TO_HINDI_DIGIT_INCREMENT (START_HINDI_DIGITS - START_FARSI_DIGITS)
#define ARABIC_TO_PERSIAN_DIGIT_INCREMENT (START_FARSI_DIGITS - START_ARABIC_DIGITS)
#define NUM_TO_ARABIC(c) \
((((c)>=START_HINDI_DIGITS) && ((c)<=END_HINDI_DIGITS)) ? \
((c) - (PRUint16)ARABIC_TO_HINDI_DIGIT_INCREMENT) : \
((((c)>=START_FARSI_DIGITS) && ((c)<=END_FARSI_DIGITS)) ? \
((c) - (PRUint16)ARABIC_TO_PERSIAN_DIGIT_INCREMENT) : \
(c)))
#define NUM_TO_HINDI(c) \
((((c)>=START_ARABIC_DIGITS) && ((c)<=END_ARABIC_DIGITS)) ? \
((c) + (PRUint16)ARABIC_TO_HINDI_DIGIT_INCREMENT): \
((((c)>=START_FARSI_DIGITS) && ((c)<=END_FARSI_DIGITS)) ? \
((c) + (PRUint16)PERSIAN_TO_HINDI_DIGIT_INCREMENT) : \
(c)))
#define NUM_TO_PERSIAN(c) \
((((c)>=START_HINDI_DIGITS) && ((c)<=END_HINDI_DIGITS)) ? \
((c) - (PRUint16)PERSIAN_TO_HINDI_DIGIT_INCREMENT) : \
((((c)>=START_ARABIC_DIGITS) && ((c)<=END_ARABIC_DIGITS)) ? \
((c) + (PRUint16)ARABIC_TO_PERSIAN_DIGIT_INCREMENT) : \
(c)))
PRUnichar HandleNumberInChar(PRUnichar aChar, PRBool aPrevCharArabic, PRUint32 aNumFlag)
{
// IBMBIDI_NUMERAL_NOMINAL *
// IBMBIDI_NUMERAL_REGULAR
// IBMBIDI_NUMERAL_HINDICONTEXT
// IBMBIDI_NUMERAL_ARABIC
// IBMBIDI_NUMERAL_HINDI
switch (aNumFlag) {
case IBMBIDI_NUMERAL_HINDI:
return NUM_TO_HINDI(aChar);
case IBMBIDI_NUMERAL_ARABIC:
return NUM_TO_ARABIC(aChar);
case IBMBIDI_NUMERAL_PERSIAN:
return NUM_TO_PERSIAN(aChar);
case IBMBIDI_NUMERAL_REGULAR:
case IBMBIDI_NUMERAL_HINDICONTEXT:
case IBMBIDI_NUMERAL_PERSIANCONTEXT:
// for clipboard handling
//XXX do we really want to convert numerals when copying text?
if (aPrevCharArabic) {
if (aNumFlag == IBMBIDI_NUMERAL_PERSIANCONTEXT)
return NUM_TO_PERSIAN(aChar);
else
return NUM_TO_HINDI(aChar);
}
else
return NUM_TO_ARABIC(aChar);
case IBMBIDI_NUMERAL_NOMINAL:
default:
return aChar;
}
}
nsresult HandleNumbers(PRUnichar* aBuffer, PRUint32 aSize, PRUint32 aNumFlag)
{
PRUint32 i;
switch (aNumFlag) {
case IBMBIDI_NUMERAL_HINDI:
case IBMBIDI_NUMERAL_ARABIC:
case IBMBIDI_NUMERAL_PERSIAN:
case IBMBIDI_NUMERAL_REGULAR:
case IBMBIDI_NUMERAL_HINDICONTEXT:
case IBMBIDI_NUMERAL_PERSIANCONTEXT:
for (i=0;i<aSize;i++)
aBuffer[i] = HandleNumberInChar(aBuffer[i], !!(i>0 ? aBuffer[i-1] : 0), aNumFlag);
break;
case IBMBIDI_NUMERAL_NOMINAL:
default:
break;
}
return NS_OK;
}
#define LRM_CHAR 0x200e
PRBool IsBidiControl(PRUint32 aChar)
{
// This method is used when stripping Bidi control characters for
// display, so it will return TRUE for LRM and RLM as
// well as the characters with category eBidiCat_CC
return (eBidiCat_CC == GetBidiCat(aChar) || ((aChar)&0xfffffe)==LRM_CHAR);
}
PRBool HasRTLChars(const nsAString& aString)
{
// This is used to determine whether to enable bidi if a string has
// right-to-left characters. To simplify things, anything that could be a
// surrogate or RTL presentation form is covered just by testing >= 0xD800).
// It's fine to enable bidi in rare cases where it actually isn't needed.
PRInt32 length = aString.Length();
for (PRInt32 i = 0; i < length; i++) {
PRUnichar ch = aString.CharAt(i);
if (ch >= 0xD800 || IS_IN_BMP_RTL_BLOCK(ch)) {
return PR_TRUE;
}
}
return PR_FALSE;
}
nsCharType GetCharType(PRUint32 aChar)
{
nsCharType oResult;
eBidiCategory bCat = GetBidiCat(aChar);
if (eBidiCat_CC != bCat) {
NS_ASSERTION((PRUint32) bCat < (sizeof(ebc2ucd)/sizeof(nsCharType)), "size mismatch");
if((PRUint32) bCat < (sizeof(ebc2ucd)/sizeof(nsCharType)))
oResult = ebc2ucd[bCat];
else
oResult = ebc2ucd[0]; // something is very wrong, but we need to return a value
} else {
NS_ASSERTION((aChar-0x202a) < (sizeof(cc2ucd)/sizeof(nsCharType)), "size mismatch");
if((aChar-0x202a) < (sizeof(cc2ucd)/sizeof(nsCharType)))
oResult = cc2ucd[aChar - 0x202a];
else
oResult = ebc2ucd[0]; // something is very wrong, but we need to return a value
}
return oResult;
}