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efl/src/static_libs/libunibreak/linebreak.c

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/* vim: set expandtab tabstop=4 softtabstop=4 shiftwidth=4: */
/*
* Line breaking in a Unicode sequence. Designed to be used in a
* generic text renderer.
*
* Copyright (C) 2008-2019 Wu Yongwei <wuyongwei at gmail dot com>
* Copyright (C) 2013 Petr Filipsky <philodej at gmail dot com>
*
* This software is provided 'as-is', without any express or implied
* warranty. In no event will the author be held liable for any damages
* arising from the use of this software.
*
* Permission is granted to anyone to use this software for any purpose,
* including commercial applications, and to alter it and redistribute
* it freely, subject to the following restrictions:
*
* 1. The origin of this software must not be misrepresented; you must
* not claim that you wrote the original software. If you use this
* software in a product, an acknowledgement in the product
* documentation would be appreciated but is not required.
* 2. Altered source versions must be plainly marked as such, and must
* not be misrepresented as being the original software.
* 3. This notice may not be removed or altered from any source
* distribution.
*
* The main reference is Unicode Standard Annex 14 (UAX #14):
* <URL:http://www.unicode.org/reports/tr14/>
*
* When this library was designed, this annex was at Revision 19, for
* Unicode 5.0.0:
* <URL:http://www.unicode.org/reports/tr14/tr14-19.html>
*
* This library has been updated according to Revision 43, for
* Unicode 12.0.0:
* <URL:http://www.unicode.org/reports/tr14/tr14-43.html>
*
* The Unicode Terms of Use are available at
* <URL:http://www.unicode.org/copyright.html>
*/
/**
* @file linebreak.c
*
* Implementation of the line breaking algorithm as described in Unicode
* Standard Annex 14.
*
* @author Wu Yongwei
* @author Petr Filipsky
*/
#include <assert.h>
#include <stddef.h>
#include <string.h>
#include "linebreak.h"
#include "linebreakdef.h"
/**
* Special value used internally to indicate an undefined break result.
*/
#define LINEBREAK_UNDEFINED -1
/**
* Size of the second-level index to the line breaking properties.
*/
#define LINEBREAK_INDEX_SIZE 40
/**
* Enumeration of break actions. They are used in the break action
* pair table #baTable.
*/
enum BreakAction
{
DIR_BRK, /**< Direct break opportunity */
IND_BRK, /**< Indirect break opportunity */
CMI_BRK, /**< Indirect break opportunity for combining marks */
CMP_BRK, /**< Prohibited break for combining marks */
PRH_BRK /**< Prohibited break */
};
/**
* Break action pair table. This is a direct mapping of Table 2 of
* Unicode Standard Annex 14, Revision 37, except for ZWJ (manually
* adjusted after special processing as per LB8a of Revision 41) and CB
* (manually added as per LB20).
*/
static enum BreakAction baTable[LBP_CB][LBP_CB] = {
{ /* OP */
PRH_BRK, PRH_BRK, PRH_BRK, PRH_BRK, PRH_BRK, PRH_BRK, PRH_BRK,
PRH_BRK, PRH_BRK, PRH_BRK, PRH_BRK, PRH_BRK, PRH_BRK, PRH_BRK,
PRH_BRK, PRH_BRK, PRH_BRK, PRH_BRK, PRH_BRK, PRH_BRK, PRH_BRK,
CMP_BRK, PRH_BRK, PRH_BRK, PRH_BRK, PRH_BRK, PRH_BRK, PRH_BRK,
PRH_BRK, PRH_BRK, PRH_BRK, PRH_BRK, PRH_BRK },
{ /* CL */
DIR_BRK, PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, PRH_BRK, PRH_BRK,
PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, DIR_BRK, IND_BRK, IND_BRK, DIR_BRK, DIR_BRK, PRH_BRK,
CMI_BRK, PRH_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, DIR_BRK, DIR_BRK, IND_BRK, DIR_BRK },
{ /* CP */
DIR_BRK, PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, PRH_BRK, PRH_BRK,
PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK,
DIR_BRK, DIR_BRK, IND_BRK, IND_BRK, DIR_BRK, DIR_BRK, PRH_BRK,
CMI_BRK, PRH_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, DIR_BRK, DIR_BRK, IND_BRK, DIR_BRK },
{ /* QU */
PRH_BRK, PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, PRH_BRK,
PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK,
IND_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK, PRH_BRK,
CMI_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK,
IND_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK },
{ /* GL */
IND_BRK, PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, PRH_BRK,
PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK,
IND_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK, PRH_BRK,
CMI_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK,
IND_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK },
{ /* NS */
DIR_BRK, PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, PRH_BRK,
PRH_BRK, PRH_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, DIR_BRK, IND_BRK, IND_BRK, DIR_BRK, DIR_BRK, PRH_BRK,
CMI_BRK, PRH_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, DIR_BRK, DIR_BRK, IND_BRK, DIR_BRK },
{ /* EX */
DIR_BRK, PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, PRH_BRK,
PRH_BRK, PRH_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, IND_BRK, IND_BRK, IND_BRK, DIR_BRK, DIR_BRK, PRH_BRK,
CMI_BRK, PRH_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, DIR_BRK, DIR_BRK, IND_BRK, DIR_BRK },
{ /* SY */
DIR_BRK, PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, PRH_BRK,
PRH_BRK, PRH_BRK, DIR_BRK, DIR_BRK, IND_BRK, DIR_BRK, IND_BRK,
DIR_BRK, DIR_BRK, IND_BRK, IND_BRK, DIR_BRK, DIR_BRK, PRH_BRK,
CMI_BRK, PRH_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, DIR_BRK, DIR_BRK, IND_BRK, DIR_BRK },
{ /* IS */
DIR_BRK, PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, PRH_BRK,
PRH_BRK, PRH_BRK, DIR_BRK, DIR_BRK, IND_BRK, IND_BRK, IND_BRK,
DIR_BRK, DIR_BRK, IND_BRK, IND_BRK, DIR_BRK, DIR_BRK, PRH_BRK,
CMI_BRK, PRH_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, DIR_BRK, DIR_BRK, IND_BRK, DIR_BRK },
{ /* PR */
IND_BRK, PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, PRH_BRK,
PRH_BRK, PRH_BRK, DIR_BRK, DIR_BRK, IND_BRK, IND_BRK, IND_BRK,
IND_BRK, DIR_BRK, IND_BRK, IND_BRK, DIR_BRK, DIR_BRK, PRH_BRK,
CMI_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK,
DIR_BRK, IND_BRK, IND_BRK, IND_BRK, DIR_BRK },
{ /* PO */
IND_BRK, PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, PRH_BRK,
PRH_BRK, PRH_BRK, DIR_BRK, DIR_BRK, IND_BRK, IND_BRK, IND_BRK,
DIR_BRK, DIR_BRK, IND_BRK, IND_BRK, DIR_BRK, DIR_BRK, PRH_BRK,
CMI_BRK, PRH_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, DIR_BRK, DIR_BRK, IND_BRK, DIR_BRK },
{ /* NU */
IND_BRK, PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, PRH_BRK,
PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK,
DIR_BRK, IND_BRK, IND_BRK, IND_BRK, DIR_BRK, DIR_BRK, PRH_BRK,
CMI_BRK, PRH_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, DIR_BRK, DIR_BRK, IND_BRK, DIR_BRK },
{ /* AL */
IND_BRK, PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, PRH_BRK,
PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK,
DIR_BRK, IND_BRK, IND_BRK, IND_BRK, DIR_BRK, DIR_BRK, PRH_BRK,
CMI_BRK, PRH_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, DIR_BRK, DIR_BRK, IND_BRK, DIR_BRK },
{ /* HL */
IND_BRK, PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, PRH_BRK,
PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK,
DIR_BRK, IND_BRK, IND_BRK, IND_BRK, DIR_BRK, DIR_BRK, PRH_BRK,
CMI_BRK, PRH_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, DIR_BRK, DIR_BRK, IND_BRK, DIR_BRK },
{ /* ID */
DIR_BRK, PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, PRH_BRK,
PRH_BRK, PRH_BRK, DIR_BRK, IND_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, IND_BRK, IND_BRK, IND_BRK, DIR_BRK, DIR_BRK, PRH_BRK,
CMI_BRK, PRH_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, DIR_BRK, DIR_BRK, IND_BRK, DIR_BRK },
{ /* IN */
DIR_BRK, PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, PRH_BRK,
PRH_BRK, PRH_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, IND_BRK, IND_BRK, IND_BRK, DIR_BRK, DIR_BRK, PRH_BRK,
CMI_BRK, PRH_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, DIR_BRK, DIR_BRK, IND_BRK, DIR_BRK },
{ /* HY */
DIR_BRK, PRH_BRK, PRH_BRK, IND_BRK, DIR_BRK, IND_BRK, PRH_BRK,
PRH_BRK, PRH_BRK, DIR_BRK, DIR_BRK, IND_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, DIR_BRK, IND_BRK, IND_BRK, DIR_BRK, DIR_BRK, PRH_BRK,
CMI_BRK, PRH_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, DIR_BRK, DIR_BRK, IND_BRK, DIR_BRK },
{ /* BA */
DIR_BRK, PRH_BRK, PRH_BRK, IND_BRK, DIR_BRK, IND_BRK, PRH_BRK,
PRH_BRK, PRH_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, DIR_BRK, IND_BRK, IND_BRK, DIR_BRK, DIR_BRK, PRH_BRK,
CMI_BRK, PRH_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, DIR_BRK, DIR_BRK, IND_BRK, DIR_BRK },
{ /* BB */
IND_BRK, PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, PRH_BRK,
PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK,
IND_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK, PRH_BRK,
CMI_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK,
IND_BRK, IND_BRK, IND_BRK, IND_BRK, DIR_BRK },
{ /* B2 */
DIR_BRK, PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, PRH_BRK,
PRH_BRK, PRH_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, DIR_BRK, IND_BRK, IND_BRK, DIR_BRK, PRH_BRK, PRH_BRK,
CMI_BRK, PRH_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, DIR_BRK, DIR_BRK, IND_BRK, DIR_BRK },
{ /* ZW */
DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, PRH_BRK,
DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK },
{ /* CM */
IND_BRK, PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, PRH_BRK,
PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK,
DIR_BRK, IND_BRK, IND_BRK, IND_BRK, DIR_BRK, DIR_BRK, PRH_BRK,
CMI_BRK, PRH_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, DIR_BRK, DIR_BRK, IND_BRK, DIR_BRK },
{ /* WJ */
IND_BRK, PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, PRH_BRK,
PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK,
IND_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK, PRH_BRK,
CMI_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK,
IND_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK },
{ /* H2 */
DIR_BRK, PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, PRH_BRK,
PRH_BRK, PRH_BRK, DIR_BRK, IND_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, IND_BRK, IND_BRK, IND_BRK, DIR_BRK, DIR_BRK, PRH_BRK,
CMI_BRK, PRH_BRK, DIR_BRK, DIR_BRK, DIR_BRK, IND_BRK, IND_BRK,
DIR_BRK, DIR_BRK, DIR_BRK, IND_BRK, DIR_BRK },
{ /* H3 */
DIR_BRK, PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, PRH_BRK,
PRH_BRK, PRH_BRK, DIR_BRK, IND_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, IND_BRK, IND_BRK, IND_BRK, DIR_BRK, DIR_BRK, PRH_BRK,
CMI_BRK, PRH_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, IND_BRK,
DIR_BRK, DIR_BRK, DIR_BRK, IND_BRK, DIR_BRK },
{ /* JL */
DIR_BRK, PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, PRH_BRK,
PRH_BRK, PRH_BRK, DIR_BRK, IND_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, IND_BRK, IND_BRK, IND_BRK, DIR_BRK, DIR_BRK, PRH_BRK,
CMI_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK, DIR_BRK,
DIR_BRK, DIR_BRK, DIR_BRK, IND_BRK, DIR_BRK },
{ /* JV */
DIR_BRK, PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, PRH_BRK,
PRH_BRK, PRH_BRK, DIR_BRK, IND_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, IND_BRK, IND_BRK, IND_BRK, DIR_BRK, DIR_BRK, PRH_BRK,
CMI_BRK, PRH_BRK, DIR_BRK, DIR_BRK, DIR_BRK, IND_BRK, IND_BRK,
DIR_BRK, DIR_BRK, DIR_BRK, IND_BRK, DIR_BRK },
{ /* JT */
DIR_BRK, PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, PRH_BRK,
PRH_BRK, PRH_BRK, DIR_BRK, IND_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, IND_BRK, IND_BRK, IND_BRK, DIR_BRK, DIR_BRK, PRH_BRK,
CMI_BRK, PRH_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, IND_BRK,
DIR_BRK, DIR_BRK, DIR_BRK, IND_BRK, DIR_BRK },
{ /* RI */
DIR_BRK, PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, PRH_BRK,
PRH_BRK, PRH_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, DIR_BRK, IND_BRK, IND_BRK, DIR_BRK, DIR_BRK, PRH_BRK,
CMI_BRK, PRH_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
IND_BRK, DIR_BRK, DIR_BRK, IND_BRK, DIR_BRK },
{ /* EB */
DIR_BRK, PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, PRH_BRK,
PRH_BRK, PRH_BRK, DIR_BRK, IND_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, IND_BRK, IND_BRK, IND_BRK, DIR_BRK, DIR_BRK, PRH_BRK,
CMI_BRK, PRH_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, DIR_BRK, IND_BRK, IND_BRK, DIR_BRK },
{ /* EM */
DIR_BRK, PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, PRH_BRK,
PRH_BRK, PRH_BRK, DIR_BRK, IND_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, IND_BRK, IND_BRK, IND_BRK, DIR_BRK, DIR_BRK, PRH_BRK,
CMI_BRK, PRH_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, DIR_BRK, DIR_BRK, IND_BRK, DIR_BRK },
{ /* ZWJ */
IND_BRK, PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, PRH_BRK,
PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK, IND_BRK,
DIR_BRK, IND_BRK, IND_BRK, IND_BRK, DIR_BRK, DIR_BRK, PRH_BRK,
CMI_BRK, PRH_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, DIR_BRK, DIR_BRK, IND_BRK, DIR_BRK },
{ /* CB */
DIR_BRK, PRH_BRK, PRH_BRK, IND_BRK, IND_BRK, DIR_BRK, PRH_BRK,
PRH_BRK, PRH_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, PRH_BRK,
CMI_BRK, PRH_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK, DIR_BRK,
DIR_BRK, DIR_BRK, DIR_BRK, IND_BRK, DIR_BRK },
};
/**
* Struct for the second-level index to the line breaking properties.
*/
struct LineBreakPropertiesIndex
{
utf32_t end; /**< End codepoint */
const struct LineBreakProperties *lbp; /**< Pointer to line breaking
properties */
};
/**
* Second-level index to the line breaking properties.
*/
static struct LineBreakPropertiesIndex lb_prop_index[LINEBREAK_INDEX_SIZE] =
{
{ 0xFFFFFFFF, lb_prop_default }
};
/**
* Checks whether the \a str ends with \a suffix, which has length
* \a suffix_len.
*
* @param str string whose ending is to be checked
* @param suffix string to check
* @param suffixLen length of \a suffix
* @return non-zero if true; zero otherwise
*/
static __inline int ends_with(const char *str, const char *suffix,
unsigned suffixLen)
{
unsigned len;
if (str == NULL)
{
return 0;
}
len = strlen(str);
if (len >= suffixLen &&
memcmp(str + len - suffixLen, suffix, suffixLen) == 0)
{
return 1;
}
else
{
return 0;
}
}
#define ENDS_WITH(str, suffix) ends_with((str), (suffix), sizeof(suffix) - 1)
/**
* Initializes the second-level index to the line breaking properties.
* If it is not called, the performance of #get_char_lb_class_lang (and
* thus the main functionality) can be pretty bad, especially for big
* codepoints like those of Chinese.
*/
void init_linebreak(void)
{
size_t i;
size_t iPropDefault;
size_t len;
size_t step;
len = 0;
while (lb_prop_default[len].prop != LBP_Undefined)
++len;
step = len / LINEBREAK_INDEX_SIZE;
iPropDefault = 0;
for (i = 0; i < LINEBREAK_INDEX_SIZE; ++i)
{
lb_prop_index[i].lbp = lb_prop_default + iPropDefault;
iPropDefault += step;
lb_prop_index[i].end = lb_prop_default[iPropDefault].start - 1;
}
lb_prop_index[--i].end = 0xFFFFFFFF;
}
/**
* Gets the language-specific line breaking properties.
*
* @param lang language of the text
* @return pointer to the language-specific line breaking
* properties array if found; \c NULL otherwise
*/
static const struct LineBreakProperties *get_lb_prop_lang(const char *lang)
{
const struct LineBreakPropertiesLang *lbplIter;
if (lang != NULL)
{
for (lbplIter = lb_prop_lang_map; lbplIter->lang != NULL; ++lbplIter)
{
if (strncmp(lang, lbplIter->lang, lbplIter->namelen) == 0)
{
return lbplIter->lbp;
}
}
}
return NULL;
}
/**
* Gets the line breaking class of a character from a line breaking
* properties array.
*
* @param ch character to check
* @param lbp pointer to the line breaking properties array
* @return the line breaking class if found; \c LBP_XX otherwise
*/
static enum LineBreakClass get_char_lb_class(
utf32_t ch,
const struct LineBreakProperties *lbp)
{
while (lbp->prop != LBP_Undefined && ch >= lbp->start)
{
if (ch <= lbp->end)
return lbp->prop;
++lbp;
}
return LBP_XX;
}
/**
* Gets the line breaking class of a character from the default line
* breaking properties array.
*
* @param ch character to check
* @return the line breaking class if found; \c LBP_XX otherwise
*/
static enum LineBreakClass get_char_lb_class_default(
utf32_t ch)
{
size_t i = 0;
while (ch > lb_prop_index[i].end)
++i;
assert(i < LINEBREAK_INDEX_SIZE);
return get_char_lb_class(ch, lb_prop_index[i].lbp);
}
/**
* Gets the line breaking class of a character for a specific
* language. This function will check the language-specific data first,
* and then the default data if there is no language-specific property
* available for the character.
*
* @param ch character to check
* @param lbpLang pointer to the language-specific line breaking
* properties array
* @return the line breaking class if found; \c LBP_XX
* otherwise
*/
static enum LineBreakClass get_char_lb_class_lang(
utf32_t ch,
const struct LineBreakProperties *lbpLang)
{
enum LineBreakClass lbcResult;
/* Find the language-specific line breaking class for a character */
if (lbpLang)
{
lbcResult = get_char_lb_class(ch, lbpLang);
if (lbcResult != LBP_XX)
return lbcResult;
}
/* Find the generic language-specific line breaking class, if no
* language context is provided, or language-specific data are not
* available for the specific character in the specified language */
return get_char_lb_class_default(ch);
}
/**
* Resolves the line breaking class for certain ambiguous or complicated
* characters. They are treated in a simplistic way in this
* implementation.
*
* @param lbc line breaking class to resolve
* @param lang language of the text
* @return the resolved line breaking class
*/
static enum LineBreakClass resolve_lb_class(
enum LineBreakClass lbc,
const char *lang)
{
switch (lbc)
{
case LBP_AI:
if (lang != NULL &&
(strncmp(lang, "zh", 2) == 0 || /* Chinese */
strncmp(lang, "ja", 2) == 0 || /* Japanese */
strncmp(lang, "ko", 2) == 0)) /* Korean */
{
return LBP_ID;
}
else
{
return LBP_AL;
}
case LBP_CJ:
/* `Strict' and `normal' line breaking. See
* <url:http://www.unicode.org/reports/tr14/#CJ>
* for details. */
if (ENDS_WITH(lang, "-strict"))
{
return LBP_NS;
}
else
{
return LBP_ID;
}
case LBP_SA:
case LBP_SG:
case LBP_XX:
return LBP_AL;
default:
return lbc;
}
}
/**
* Treats specially for the first character in a line.
*
* @param[in,out] lbpCtx pointer to the line breaking context
* @pre \a lbpCtx->lbcCur has a valid line break class
* @post \a lbpCtx->lbcCur has the updated line break class
*/
static void treat_first_char(
struct LineBreakContext *lbpCtx)
{
switch (lbpCtx->lbcCur)
{
case LBP_LF:
case LBP_NL:
lbpCtx->lbcCur = LBP_BK; /* Rule LB5 */
break;
case LBP_SP:
lbpCtx->lbcCur = LBP_WJ; /* Leading space treated as WJ */
break;
default:
break;
}
}
/**
* Tries telling the line break opportunity by simple rules.
*
* @param[in,out] lbpCtx pointer to the line breaking context
* @pre \a lbpCtx->lbcCur has the current line break
* class; and \a lbpCtx->lbcNew has the line
* break class for the next character
* @post \a lbpCtx->lbcCur has the updated line break
* class
* @return break result, one of #LINEBREAK_MUSTBREAK,
* #LINEBREAK_ALLOWBREAK, and #LINEBREAK_NOBREAK
* if identified; or #LINEBREAK_UNDEFINED if
* table lookup is needed
*/
static int get_lb_result_simple(
struct LineBreakContext *lbpCtx)
{
if (lbpCtx->lbcCur == LBP_BK
|| (lbpCtx->lbcCur == LBP_CR && lbpCtx->lbcNew != LBP_LF))
{
return LINEBREAK_MUSTBREAK; /* Rules LB4 and LB5 */
}
switch (lbpCtx->lbcNew)
{
case LBP_SP:
return LINEBREAK_NOBREAK; /* Rule LB7; no change to lbcCur */
case LBP_BK:
case LBP_LF:
case LBP_NL:
lbpCtx->lbcCur = LBP_BK; /* Mandatory break after */
return LINEBREAK_NOBREAK; /* Rule LB6 */
case LBP_CR:
lbpCtx->lbcCur = LBP_CR;
return LINEBREAK_NOBREAK; /* Rule LB6 */
default:
return LINEBREAK_UNDEFINED; /* Table lookup is needed */
}
}
/**
* Tells the line break opportunity by table lookup.
*
* @param[in,out] lbpCtx pointer to the line breaking context
* @pre \a lbpCtx->lbcCur has the current line break
* class; \a lbpCtx->lbcLast has the line break
* class for the last character; and \a
* lbcCur->lbcNew has the line break class for
* the next character
* @post \a lbpCtx->lbcCur has the updated line break
* class
* @return break result, one of #LINEBREAK_MUSTBREAK,
* #LINEBREAK_ALLOWBREAK, and #LINEBREAK_NOBREAK
*/
static int get_lb_result_lookup(
struct LineBreakContext *lbpCtx)
{
int brk = LINEBREAK_UNDEFINED;
assert(lbpCtx->lbcCur <= LBP_CB);
assert(lbpCtx->lbcNew <= LBP_CB);
switch (baTable[lbpCtx->lbcCur - 1][lbpCtx->lbcNew - 1])
{
case DIR_BRK:
brk = LINEBREAK_ALLOWBREAK;
break;
case IND_BRK:
brk = (lbpCtx->lbcLast == LBP_SP)
? LINEBREAK_ALLOWBREAK
: LINEBREAK_NOBREAK;
break;
case CMI_BRK:
brk = LINEBREAK_ALLOWBREAK;
if (lbpCtx->lbcLast != LBP_SP)
{
brk = LINEBREAK_NOBREAK;
return brk; /* Do not update lbcCur */
}
break;
case CMP_BRK:
brk = LINEBREAK_NOBREAK;
if (lbpCtx->lbcLast != LBP_SP)
return brk; /* Do not update lbcCur */
break;
case PRH_BRK:
brk = LINEBREAK_NOBREAK;
break;
}
/* Special processing due to rule LB8a */
if (lbpCtx->fLb8aZwj)
{
brk = LINEBREAK_NOBREAK;
}
/* Special processing due to rule LB21a */
if (lbpCtx->fLb21aHebrew &&
(lbpCtx->lbcCur == LBP_HY || lbpCtx->lbcCur == LBP_BA))
{
brk = LINEBREAK_NOBREAK;
lbpCtx->fLb21aHebrew = false;
}
else
{
lbpCtx->fLb21aHebrew = (lbpCtx->lbcCur == LBP_HL);
}
/* Special processing due to rule LB30a */
if (lbpCtx->lbcCur == LBP_RI)
{
lbpCtx->cLb30aRI++;
if (lbpCtx->cLb30aRI == 2 && lbpCtx->lbcNew == LBP_RI)
{
brk = LINEBREAK_ALLOWBREAK;
lbpCtx->cLb30aRI = 0;
}
}
else
{
lbpCtx->cLb30aRI = 0;
}
lbpCtx->lbcCur = lbpCtx->lbcNew;
return brk;
}
/**
* Initializes line breaking context for a given language.
*
* @param[in,out] lbpCtx pointer to the line breaking context
* @param[in] ch the first character to process
* @param[in] lang language of the input
* @post the line breaking context is initialized
*/
void lb_init_break_context(
struct LineBreakContext *lbpCtx,
utf32_t ch,
const char *lang)
{
lbpCtx->lang = lang;
lbpCtx->lbpLang = get_lb_prop_lang(lang);
lbpCtx->lbcLast = LBP_Undefined;
lbpCtx->lbcNew = LBP_Undefined;
lbpCtx->lbcCur = resolve_lb_class(
get_char_lb_class_lang(ch, lbpCtx->lbpLang),
lbpCtx->lang);
lbpCtx->fLb8aZwj =
(get_char_lb_class_lang(ch, lbpCtx->lbpLang) == LBP_ZWJ);
lbpCtx->fLb10LeadSpace =
(get_char_lb_class_lang(ch, lbpCtx->lbpLang) == LBP_SP);
lbpCtx->fLb21aHebrew = false;
lbpCtx->cLb30aRI = 0;
treat_first_char(lbpCtx);
}
/**
* Updates LineBreakingContext for the next codepoint and returns
* the detected break.
*
* @param[in,out] lbpCtx pointer to the line breaking context
* @param[in] ch Unicode codepoint
* @return break result, one of #LINEBREAK_MUSTBREAK,
* #LINEBREAK_ALLOWBREAK, and #LINEBREAK_NOBREAK
* @post the line breaking context is updated
*/
int lb_process_next_char(
struct LineBreakContext *lbpCtx,
utf32_t ch )
{
int brk;
lbpCtx->lbcLast = lbpCtx->lbcNew;
lbpCtx->lbcNew = get_char_lb_class_lang(ch, lbpCtx->lbpLang);
brk = get_lb_result_simple(lbpCtx);
switch (brk)
{
case LINEBREAK_MUSTBREAK:
lbpCtx->lbcCur = resolve_lb_class(lbpCtx->lbcNew, lbpCtx->lang);
treat_first_char(lbpCtx);
break;
case LINEBREAK_UNDEFINED:
lbpCtx->lbcNew = resolve_lb_class(lbpCtx->lbcNew, lbpCtx->lang);
brk = get_lb_result_lookup(lbpCtx);
break;
default:
break;
}
/* Special processing due to rule LB8a */
if (lbpCtx->lbcNew == LBP_ZWJ)
{
lbpCtx->fLb8aZwj = true;
}
else
{
lbpCtx->fLb8aZwj = false;
}
/* Special processing due to rule LB10 */
if (lbpCtx->fLb10LeadSpace)
{
if (lbpCtx->lbcNew == LBP_CM || lbpCtx->lbcNew == LBP_ZWJ)
brk = LINEBREAK_ALLOWBREAK;
lbpCtx->fLb10LeadSpace = false;
}
return brk;
}
/**
* Sets the line breaking information for a generic input string.
*
* Currently, this implementation has customization for the following
* ISO 639-1 language codes (for \a lang):
*
* - de (German)
* - en (English)
* - es (Spanish)
* - fr (French)
* - ja (Japanese)
* - ko (Korean)
* - ru (Russian)
* - zh (Chinese)
*
* In addition, a suffix <code>"-strict"</code> may be added to indicate
* strict (as versus normal) line-breaking behaviour. See the <a
* href="http://www.unicode.org/reports/tr14/#CJ">Conditional Japanese
* Starter section of UAX #14</a> for more details.
*
* @param[in] s input string
* @param[in] len length of the input
* @param[in] lang language of the input
* @param[out] brks pointer to the output breaking data,
* containing #LINEBREAK_MUSTBREAK,
* #LINEBREAK_ALLOWBREAK, #LINEBREAK_NOBREAK,
* or #LINEBREAK_INSIDEACHAR
* @param[in] get_next_char function to get the next UTF-32 character
*/
void set_linebreaks(
const void *s,
size_t len,
const char *lang,
char *brks,
get_next_char_t get_next_char)
{
utf32_t ch;
struct LineBreakContext lbCtx;
size_t posCur = 0;
size_t posLast = 0;
--posLast; /* To be ++'d later */
ch = get_next_char(s, len, &posCur);
if (ch == EOS)
return;
lb_init_break_context(&lbCtx, ch, lang);
/* Process a line till an explicit break or end of string */
for (;;)
{
for (++posLast; posLast < posCur - 1; ++posLast)
{
brks[posLast] = LINEBREAK_INSIDEACHAR;
}
assert(posLast == posCur - 1);
ch = get_next_char(s, len, &posCur);
if (ch == EOS)
break;
brks[posLast] = lb_process_next_char(&lbCtx, ch);
}
assert(posLast == posCur - 1 && posCur <= len);
/* Break after the last character */
brks[posLast] = LINEBREAK_MUSTBREAK;
/* When the input contains incomplete sequences */
while (posCur < len)
{
brks[posCur++] = LINEBREAK_INSIDEACHAR;
}
}
/**
* Sets the line breaking information for a UTF-8 input string.
*
* @param[in] s input UTF-8 string
* @param[in] len length of the input
* @param[in] lang language of the input
* @param[out] brks pointer to the output breaking data, containing
* #LINEBREAK_MUSTBREAK, #LINEBREAK_ALLOWBREAK,
* #LINEBREAK_NOBREAK, or #LINEBREAK_INSIDEACHAR
* @see #set_linebreaks for a note about \a lang.
*/
void set_linebreaks_utf8(
const utf8_t *s,
size_t len,
const char *lang,
char *brks)
{
set_linebreaks(s, len, lang, brks,
(get_next_char_t)ub_get_next_char_utf8);
}
/**
* Sets the line breaking information for a UTF-16 input string.
*
* @param[in] s input UTF-16 string
* @param[in] len length of the input
* @param[in] lang language of the input
* @param[out] brks pointer to the output breaking data, containing
* #LINEBREAK_MUSTBREAK, #LINEBREAK_ALLOWBREAK,
* #LINEBREAK_NOBREAK, or #LINEBREAK_INSIDEACHAR
* @see #set_linebreaks for a note about \a lang.
*/
void set_linebreaks_utf16(
const utf16_t *s,
size_t len,
const char *lang,
char *brks)
{
set_linebreaks(s, len, lang, brks,
(get_next_char_t)ub_get_next_char_utf16);
}
/**
* Sets the line breaking information for a UTF-32 input string.
*
* @param[in] s input UTF-32 string
* @param[in] len length of the input
* @param[in] lang language of the input
* @param[out] brks pointer to the output breaking data, containing
* #LINEBREAK_MUSTBREAK, #LINEBREAK_ALLOWBREAK,
* #LINEBREAK_NOBREAK, or #LINEBREAK_INSIDEACHAR
* @see #set_linebreaks for a note about \a lang.
*/
void set_linebreaks_utf32(
const utf32_t *s,
size_t len,
const char *lang,
char *brks)
{
set_linebreaks(s, len, lang, brks,
(get_next_char_t)ub_get_next_char_utf32);
}
/**
* Tells whether a line break can occur between two Unicode characters.
* This is a wrapper function to expose a simple interface. Generally
* speaking, it is better to use #set_linebreaks_utf32 instead, since
* complicated cases involving combining marks, spaces, etc. cannot be
* correctly processed.
*
* @param char1 the first Unicode character
* @param char2 the second Unicode character
* @param lang language of the input
* @return one of #LINEBREAK_MUSTBREAK, #LINEBREAK_ALLOWBREAK,
* #LINEBREAK_NOBREAK, or #LINEBREAK_INSIDEACHAR
*/
int is_line_breakable(
utf32_t char1,
utf32_t char2,
const char *lang)
{
utf32_t s[2];
char brks[2];
s[0] = char1;
s[1] = char2;
set_linebreaks_utf32(s, 2, lang, brks);
return brks[0];
}
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