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updated for version 7.3.220 Problem: Python 3: vim.error is a 'str' instead of an 'Exception' object, so 'except' or 'raise' it causes a 'SystemError' exception. Buffer objects do not support slice assignment. When exchanging text between Vim and Python, multibyte texts become gabage or cause Unicode Expceptions, etc. 'py3file' tries to read in the file as Unicode, sometimes causes UnicodeDecodeException Solution: Fix the problems. (lilydjwg)
author Bram Moolenaar <bram@vim.org>
date Sun, 19 Jun 2011 00:27:51 +0200
parents 3fc0f57ecb91
children f52d2ea0f81c
line wrap: on
line source

/* vi:set ts=8 sts=4 sw=4:
 *
 * VIM - Vi IMproved    by Bram Moolenaar
 *
 * Do ":help uganda"  in Vim to read copying and usage conditions.
 * Do ":help credits" in Vim to see a list of people who contributed.
 * See README.txt for an overview of the Vim source code.
 */

/*
 * arabic.c: functions for Arabic language
 *
 * Included by main.c, when FEAT_ARABIC & FEAT_GUI is defined.
 *
 * --
 *
 * Author: Nadim Shaikli & Isam Bayazidi
 *
 */

static int  A_is_a __ARGS((int cur_c));
static int  A_is_s __ARGS((int cur_c));
static int  A_is_f __ARGS((int cur_c));
static int  chg_c_a2s __ARGS((int cur_c));
static int  chg_c_a2i __ARGS((int cur_c));
static int  chg_c_a2m __ARGS((int cur_c));
static int  chg_c_a2f __ARGS((int cur_c));
static int  chg_c_i2m __ARGS((int cur_c));
static int  chg_c_f2m __ARGS((int cur_c));
static int  chg_c_laa2i __ARGS((int hid_c));
static int  chg_c_laa2f __ARGS((int hid_c));
static int  half_shape __ARGS((int c));
static int  A_firstc_laa __ARGS((int c1, int c));
static int  A_is_harakat __ARGS((int c));
static int  A_is_iso __ARGS((int c));
static int  A_is_formb __ARGS((int c));
static int  A_is_ok __ARGS((int c));
static int  A_is_valid __ARGS((int c));
static int  A_is_special __ARGS((int c));


/*
 * Returns True if c is an ISO-8859-6 shaped ARABIC letter (user entered)
 */
    static int
A_is_a(cur_c)
    int cur_c;
{
    switch (cur_c)
    {
	case a_HAMZA:
	case a_ALEF_MADDA:
	case a_ALEF_HAMZA_ABOVE:
	case a_WAW_HAMZA:
	case a_ALEF_HAMZA_BELOW:
	case a_YEH_HAMZA:
	case a_ALEF:
	case a_BEH:
	case a_TEH_MARBUTA:
	case a_TEH:
	case a_THEH:
	case a_JEEM:
	case a_HAH:
	case a_KHAH:
	case a_DAL:
	case a_THAL:
	case a_REH:
	case a_ZAIN:
	case a_SEEN:
	case a_SHEEN:
	case a_SAD:
	case a_DAD:
	case a_TAH:
	case a_ZAH:
	case a_AIN:
	case a_GHAIN:
	case a_TATWEEL:
	case a_FEH:
	case a_QAF:
	case a_KAF:
	case a_LAM:
	case a_MEEM:
	case a_NOON:
	case a_HEH:
	case a_WAW:
	case a_ALEF_MAKSURA:
	case a_YEH:
	    return TRUE;
    }

    return FALSE;
}


/*
 * Returns True if c is an Isolated Form-B ARABIC letter
 */
    static int
A_is_s(cur_c)
    int cur_c;
{
    switch (cur_c)
    {
	case a_s_HAMZA:
	case a_s_ALEF_MADDA:
	case a_s_ALEF_HAMZA_ABOVE:
	case a_s_WAW_HAMZA:
	case a_s_ALEF_HAMZA_BELOW:
	case a_s_YEH_HAMZA:
	case a_s_ALEF:
	case a_s_BEH:
	case a_s_TEH_MARBUTA:
	case a_s_TEH:
	case a_s_THEH:
	case a_s_JEEM:
	case a_s_HAH:
	case a_s_KHAH:
	case a_s_DAL:
	case a_s_THAL:
	case a_s_REH:
	case a_s_ZAIN:
	case a_s_SEEN:
	case a_s_SHEEN:
	case a_s_SAD:
	case a_s_DAD:
	case a_s_TAH:
	case a_s_ZAH:
	case a_s_AIN:
	case a_s_GHAIN:
	case a_s_FEH:
	case a_s_QAF:
	case a_s_KAF:
	case a_s_LAM:
	case a_s_MEEM:
	case a_s_NOON:
	case a_s_HEH:
	case a_s_WAW:
	case a_s_ALEF_MAKSURA:
	case a_s_YEH:
	    return TRUE;
    }

    return FALSE;
}


/*
 * Returns True if c is a Final shape of an ARABIC letter
 */
    static int
A_is_f(cur_c)
    int cur_c;
{
    switch (cur_c)
    {
	case a_f_ALEF_MADDA:
	case a_f_ALEF_HAMZA_ABOVE:
	case a_f_WAW_HAMZA:
	case a_f_ALEF_HAMZA_BELOW:
	case a_f_YEH_HAMZA:
	case a_f_ALEF:
	case a_f_BEH:
	case a_f_TEH_MARBUTA:
	case a_f_TEH:
	case a_f_THEH:
	case a_f_JEEM:
	case a_f_HAH:
	case a_f_KHAH:
	case a_f_DAL:
	case a_f_THAL:
	case a_f_REH:
	case a_f_ZAIN:
	case a_f_SEEN:
	case a_f_SHEEN:
	case a_f_SAD:
	case a_f_DAD:
	case a_f_TAH:
	case a_f_ZAH:
	case a_f_AIN:
	case a_f_GHAIN:
	case a_f_FEH:
	case a_f_QAF:
	case a_f_KAF:
	case a_f_LAM:
	case a_f_MEEM:
	case a_f_NOON:
	case a_f_HEH:
	case a_f_WAW:
	case a_f_ALEF_MAKSURA:
	case a_f_YEH:
	case a_f_LAM_ALEF_MADDA_ABOVE:
	case a_f_LAM_ALEF_HAMZA_ABOVE:
	case a_f_LAM_ALEF_HAMZA_BELOW:
	case a_f_LAM_ALEF:
	    return TRUE;
    }
    return FALSE;
}


/*
 * Change shape - from ISO-8859-6/Isolated to Form-B Isolated
 */
    static int
chg_c_a2s(cur_c)
    int cur_c;
{
    int tempc;

    switch (cur_c)
    {
	case a_HAMZA:
	    tempc = a_s_HAMZA;
	    break;
	case a_ALEF_MADDA:
	    tempc = a_s_ALEF_MADDA;
	    break;
	case a_ALEF_HAMZA_ABOVE:
	    tempc = a_s_ALEF_HAMZA_ABOVE;
	    break;
	case a_WAW_HAMZA:
	    tempc = a_s_WAW_HAMZA;
	    break;
	case a_ALEF_HAMZA_BELOW:
	    tempc = a_s_ALEF_HAMZA_BELOW;
	    break;
	case a_YEH_HAMZA:
	    tempc = a_s_YEH_HAMZA;
	    break;
	case a_ALEF:
	    tempc = a_s_ALEF;
	    break;
	case a_TEH_MARBUTA:
	    tempc = a_s_TEH_MARBUTA;
	    break;
	case a_DAL:
	    tempc = a_s_DAL;
	    break;
	case a_THAL:
	    tempc = a_s_THAL;
	    break;
	case a_REH:
	    tempc = a_s_REH;
	    break;
	case a_ZAIN:
	    tempc = a_s_ZAIN;
	    break;
	case a_TATWEEL:			/* exceptions */
	    tempc = cur_c;
	    break;
	case a_WAW:
	    tempc = a_s_WAW;
	    break;
	case a_ALEF_MAKSURA:
	    tempc = a_s_ALEF_MAKSURA;
	    break;
	case a_BEH:
	    tempc = a_s_BEH;
	    break;
	case a_TEH:
	    tempc = a_s_TEH;
	    break;
	case a_THEH:
	    tempc = a_s_THEH;
	    break;
	case a_JEEM:
	    tempc = a_s_JEEM;
	    break;
	case a_HAH:
	    tempc = a_s_HAH;
	    break;
	case a_KHAH:
	    tempc = a_s_KHAH;
	    break;
	case a_SEEN:
	    tempc = a_s_SEEN;
	    break;
	case a_SHEEN:
	    tempc = a_s_SHEEN;
	    break;
	case a_SAD:
	    tempc = a_s_SAD;
	    break;
	case a_DAD:
	    tempc = a_s_DAD;
	    break;
	case a_TAH:
	    tempc = a_s_TAH;
	    break;
	case a_ZAH:
	    tempc = a_s_ZAH;
	    break;
	case a_AIN:
	    tempc = a_s_AIN;
	    break;
	case a_GHAIN:
	    tempc = a_s_GHAIN;
	    break;
	case a_FEH:
	    tempc = a_s_FEH;
	    break;
	case a_QAF:
	    tempc = a_s_QAF;
	    break;
	case a_KAF:
	    tempc = a_s_KAF;
	    break;
	case a_LAM:
	    tempc = a_s_LAM;
	    break;
	case a_MEEM:
	    tempc = a_s_MEEM;
	    break;
	case a_NOON:
	    tempc = a_s_NOON;
	    break;
	case a_HEH:
	    tempc = a_s_HEH;
	    break;
	case a_YEH:
	    tempc = a_s_YEH;
	    break;
	default:
	    tempc = 0;
    }

    return tempc;
}


/*
 * Change shape - from ISO-8859-6/Isolated to Initial
 */
    static int
chg_c_a2i(cur_c)
    int cur_c;
{
    int tempc;

    switch (cur_c)
    {
	case a_YEH_HAMZA:
	    tempc = a_i_YEH_HAMZA;
	    break;
	case a_HAMZA:			/* exceptions */
	    tempc = a_s_HAMZA;
	    break;
	case a_ALEF_MADDA:		/* exceptions */
	    tempc = a_s_ALEF_MADDA;
	    break;
	case a_ALEF_HAMZA_ABOVE:	/* exceptions */
	    tempc = a_s_ALEF_HAMZA_ABOVE;
	    break;
	case a_WAW_HAMZA:		/* exceptions */
	    tempc = a_s_WAW_HAMZA;
	    break;
	case a_ALEF_HAMZA_BELOW:	/* exceptions */
	    tempc = a_s_ALEF_HAMZA_BELOW;
	    break;
	case a_ALEF:			/* exceptions */
	    tempc = a_s_ALEF;
	    break;
	case a_TEH_MARBUTA:		/* exceptions */
	    tempc = a_s_TEH_MARBUTA;
	    break;
	case a_DAL:			/* exceptions */
	    tempc = a_s_DAL;
	    break;
	case a_THAL:			/* exceptions */
	    tempc = a_s_THAL;
	    break;
	case a_REH:			/* exceptions */
	    tempc = a_s_REH;
	    break;
	case a_ZAIN:			/* exceptions */
	    tempc = a_s_ZAIN;
	    break;
	case a_TATWEEL:			/* exceptions */
	    tempc = cur_c;
	    break;
	case a_WAW:			/* exceptions */
	    tempc = a_s_WAW;
	    break;
	case a_ALEF_MAKSURA:		/* exceptions */
	    tempc = a_s_ALEF_MAKSURA;
	    break;
	case a_BEH:
	    tempc = a_i_BEH;
	    break;
	case a_TEH:
	    tempc = a_i_TEH;
	    break;
	case a_THEH:
	    tempc = a_i_THEH;
	    break;
	case a_JEEM:
	    tempc = a_i_JEEM;
	    break;
	case a_HAH:
	    tempc = a_i_HAH;
	    break;
	case a_KHAH:
	    tempc = a_i_KHAH;
	    break;
	case a_SEEN:
	    tempc = a_i_SEEN;
	    break;
	case a_SHEEN:
	    tempc = a_i_SHEEN;
	    break;
	case a_SAD:
	    tempc = a_i_SAD;
	    break;
	case a_DAD:
	    tempc = a_i_DAD;
	    break;
	case a_TAH:
	    tempc = a_i_TAH;
	    break;
	case a_ZAH:
	    tempc = a_i_ZAH;
	    break;
	case a_AIN:
	    tempc = a_i_AIN;
	    break;
	case a_GHAIN:
	    tempc = a_i_GHAIN;
	    break;
	case a_FEH:
	    tempc = a_i_FEH;
	    break;
	case a_QAF:
	    tempc = a_i_QAF;
	    break;
	case a_KAF:
	    tempc = a_i_KAF;
	    break;
	case a_LAM:
	    tempc = a_i_LAM;
	    break;
	case a_MEEM:
	    tempc = a_i_MEEM;
	    break;
	case a_NOON:
	    tempc = a_i_NOON;
	    break;
	case a_HEH:
	    tempc = a_i_HEH;
	    break;
	case a_YEH:
	    tempc = a_i_YEH;
	    break;
	default:
	    tempc = 0;
    }

    return tempc;
}


/*
 * Change shape - from ISO-8859-6/Isolated to Medial
 */
    static int
chg_c_a2m(cur_c)
    int cur_c;
{
    int tempc;

    switch (cur_c)
    {
	case a_HAMZA:			/* exception */
	    tempc = a_s_HAMZA;
	    break;
	case a_ALEF_MADDA:		/* exception */
	    tempc = a_f_ALEF_MADDA;
	    break;
	case a_ALEF_HAMZA_ABOVE:	/* exception */
	    tempc = a_f_ALEF_HAMZA_ABOVE;
	    break;
	case a_WAW_HAMZA:		/* exception */
	    tempc = a_f_WAW_HAMZA;
	    break;
	case a_ALEF_HAMZA_BELOW:	/* exception */
	    tempc = a_f_ALEF_HAMZA_BELOW;
	    break;
	case a_YEH_HAMZA:
	    tempc = a_m_YEH_HAMZA;
	    break;
	case a_ALEF:			/* exception */
	    tempc = a_f_ALEF;
	    break;
	case a_BEH:
	    tempc = a_m_BEH;
	    break;
	case a_TEH_MARBUTA:		/* exception */
	    tempc = a_f_TEH_MARBUTA;
	    break;
	case a_TEH:
	    tempc = a_m_TEH;
	    break;
	case a_THEH:
	    tempc = a_m_THEH;
	    break;
	case a_JEEM:
	    tempc = a_m_JEEM;
	    break;
	case a_HAH:
	    tempc = a_m_HAH;
	    break;
	case a_KHAH:
	    tempc = a_m_KHAH;
	    break;
	case a_DAL:			/* exception */
	    tempc = a_f_DAL;
	    break;
	case a_THAL:			/* exception */
	    tempc = a_f_THAL;
	    break;
	case a_REH:			/* exception */
	    tempc = a_f_REH;
	    break;
	case a_ZAIN:			/* exception */
	    tempc = a_f_ZAIN;
	    break;
	case a_SEEN:
	    tempc = a_m_SEEN;
	    break;
	case a_SHEEN:
	    tempc = a_m_SHEEN;
	    break;
	case a_SAD:
	    tempc = a_m_SAD;
	    break;
	case a_DAD:
	    tempc = a_m_DAD;
	    break;
	case a_TAH:
	    tempc = a_m_TAH;
	    break;
	case a_ZAH:
	    tempc = a_m_ZAH;
	    break;
	case a_AIN:
	    tempc = a_m_AIN;
	    break;
	case a_GHAIN:
	    tempc = a_m_GHAIN;
	    break;
	case a_TATWEEL:			/* exception */
	    tempc = cur_c;
	    break;
	case a_FEH:
	    tempc = a_m_FEH;
	    break;
	case a_QAF:
	    tempc = a_m_QAF;
	    break;
	case a_KAF:
	    tempc = a_m_KAF;
	    break;
	case a_LAM:
	    tempc = a_m_LAM;
	    break;
	case a_MEEM:
	    tempc = a_m_MEEM;
	    break;
	case a_NOON:
	    tempc = a_m_NOON;
	    break;
	case a_HEH:
	    tempc = a_m_HEH;
	    break;
	case a_WAW:			/* exception */
	    tempc = a_f_WAW;
	    break;
	case a_ALEF_MAKSURA:		/* exception */
	    tempc = a_f_ALEF_MAKSURA;
	    break;
	case a_YEH:
	    tempc = a_m_YEH;
	    break;
	default:
	    tempc = 0;
    }

    return tempc;
}


/*
 * Change shape - from ISO-8859-6/Isolated to final
 */
    static int
chg_c_a2f(cur_c)
    int cur_c;
{
    int tempc;

    /* NOTE: these encodings need to be accounted for

	a_f_ALEF_MADDA;
	a_f_ALEF_HAMZA_ABOVE;
	a_f_ALEF_HAMZA_BELOW;
	a_f_LAM_ALEF_MADDA_ABOVE;
	a_f_LAM_ALEF_HAMZA_ABOVE;
	a_f_LAM_ALEF_HAMZA_BELOW;
	*/

    switch (cur_c)
    {
	case a_HAMZA:			/* exception */
	    tempc = a_s_HAMZA;
	    break;
	case a_ALEF_MADDA:
	    tempc = a_f_ALEF_MADDA;
	    break;
	case a_ALEF_HAMZA_ABOVE:
	    tempc = a_f_ALEF_HAMZA_ABOVE;
	    break;
	case a_WAW_HAMZA:
	    tempc = a_f_WAW_HAMZA;
	    break;
	case a_ALEF_HAMZA_BELOW:
	    tempc = a_f_ALEF_HAMZA_BELOW;
	    break;
	case a_YEH_HAMZA:
	    tempc = a_f_YEH_HAMZA;
	    break;
	case a_ALEF:
	    tempc = a_f_ALEF;
	    break;
	case a_BEH:
	    tempc = a_f_BEH;
	    break;
	case a_TEH_MARBUTA:
	    tempc = a_f_TEH_MARBUTA;
	    break;
	case a_TEH:
	    tempc = a_f_TEH;
	    break;
	case a_THEH:
	    tempc = a_f_THEH;
	    break;
	case a_JEEM:
	    tempc = a_f_JEEM;
	    break;
	case a_HAH:
	    tempc = a_f_HAH;
	    break;
	case a_KHAH:
	    tempc = a_f_KHAH;
	    break;
	case a_DAL:
	    tempc = a_f_DAL;
	    break;
	case a_THAL:
	    tempc = a_f_THAL;
	    break;
	case a_REH:
	    tempc = a_f_REH;
	    break;
	case a_ZAIN:
	    tempc = a_f_ZAIN;
	    break;
	case a_SEEN:
	    tempc = a_f_SEEN;
	    break;
	case a_SHEEN:
	    tempc = a_f_SHEEN;
	    break;
	case a_SAD:
	    tempc = a_f_SAD;
	    break;
	case a_DAD:
	    tempc = a_f_DAD;
	    break;
	case a_TAH:
	    tempc = a_f_TAH;
	    break;
	case a_ZAH:
	    tempc = a_f_ZAH;
	    break;
	case a_AIN:
	    tempc = a_f_AIN;
	    break;
	case a_GHAIN:
	    tempc = a_f_GHAIN;
	    break;
	case a_TATWEEL:			/* exception */
	    tempc = cur_c;
	    break;
	case a_FEH:
	    tempc = a_f_FEH;
	    break;
	case a_QAF:
	    tempc = a_f_QAF;
	    break;
	case a_KAF:
	    tempc = a_f_KAF;
	    break;
	case a_LAM:
	    tempc = a_f_LAM;
	    break;
	case a_MEEM:
	    tempc = a_f_MEEM;
	    break;
	case a_NOON:
	    tempc = a_f_NOON;
	    break;
	case a_HEH:
	    tempc = a_f_HEH;
	    break;
	case a_WAW:
	    tempc = a_f_WAW;
	    break;
	case a_ALEF_MAKSURA:
	    tempc = a_f_ALEF_MAKSURA;
	    break;
	case a_YEH:
	    tempc = a_f_YEH;
	    break;
	default:
	    tempc = 0;
    }

    return tempc;
}


/*
 * Change shape - from Initial to Medial
 */
    static int
chg_c_i2m(cur_c)
    int cur_c;
{
    int tempc;

    switch (cur_c)
    {
	case a_i_YEH_HAMZA:
	    tempc = a_m_YEH_HAMZA;
	    break;
	case a_i_BEH:
	    tempc = a_m_BEH;
	    break;
	case a_i_TEH:
	    tempc = a_m_TEH;
	    break;
	case a_i_THEH:
	    tempc = a_m_THEH;
	    break;
	case a_i_JEEM:
	    tempc = a_m_JEEM;
	    break;
	case a_i_HAH:
	    tempc = a_m_HAH;
	    break;
	case a_i_KHAH:
	    tempc = a_m_KHAH;
	    break;
	case a_i_SEEN:
	    tempc = a_m_SEEN;
	    break;
	case a_i_SHEEN:
	    tempc = a_m_SHEEN;
	    break;
	case a_i_SAD:
	    tempc = a_m_SAD;
	    break;
	case a_i_DAD:
	    tempc = a_m_DAD;
	    break;
	case a_i_TAH:
	    tempc = a_m_TAH;
	    break;
	case a_i_ZAH:
	    tempc = a_m_ZAH;
	    break;
	case a_i_AIN:
	    tempc = a_m_AIN;
	    break;
	case a_i_GHAIN:
	    tempc = a_m_GHAIN;
	    break;
	case a_i_FEH:
	    tempc = a_m_FEH;
	    break;
	case a_i_QAF:
	    tempc = a_m_QAF;
	    break;
	case a_i_KAF:
	    tempc = a_m_KAF;
	    break;
	case a_i_LAM:
	    tempc = a_m_LAM;
	    break;
	case a_i_MEEM:
	    tempc = a_m_MEEM;
	    break;
	case a_i_NOON:
	    tempc = a_m_NOON;
	    break;
	case a_i_HEH:
	    tempc = a_m_HEH;
	    break;
	case a_i_YEH:
	    tempc = a_m_YEH;
	    break;
	default:
	    tempc = 0;
    }

    return tempc;
}


/*
 * Change shape - from Final to Medial
 */
    static int
chg_c_f2m(cur_c)
    int cur_c;
{
    int tempc;

    switch (cur_c)
    {
	/* NOTE: these encodings are multi-positional, no ?
	   case a_f_ALEF_MADDA:
	   case a_f_ALEF_HAMZA_ABOVE:
	   case a_f_ALEF_HAMZA_BELOW:
	   */
	case a_f_YEH_HAMZA:
	    tempc = a_m_YEH_HAMZA;
	    break;
	case a_f_WAW_HAMZA:		/* exceptions */
	case a_f_ALEF:
	case a_f_TEH_MARBUTA:
	case a_f_DAL:
	case a_f_THAL:
	case a_f_REH:
	case a_f_ZAIN:
	case a_f_WAW:
	case a_f_ALEF_MAKSURA:
	    tempc = cur_c;
	    break;
	case a_f_BEH:
	    tempc = a_m_BEH;
	    break;
	case a_f_TEH:
	    tempc = a_m_TEH;
	    break;
	case a_f_THEH:
	    tempc = a_m_THEH;
	    break;
	case a_f_JEEM:
	    tempc = a_m_JEEM;
	    break;
	case a_f_HAH:
	    tempc = a_m_HAH;
	    break;
	case a_f_KHAH:
	    tempc = a_m_KHAH;
	    break;
	case a_f_SEEN:
	    tempc = a_m_SEEN;
	    break;
	case a_f_SHEEN:
	    tempc = a_m_SHEEN;
	    break;
	case a_f_SAD:
	    tempc = a_m_SAD;
	    break;
	case a_f_DAD:
	    tempc = a_m_DAD;
	    break;
	case a_f_TAH:
	    tempc = a_m_TAH;
	    break;
	case a_f_ZAH:
	    tempc = a_m_ZAH;
	    break;
	case a_f_AIN:
	    tempc = a_m_AIN;
	    break;
	case a_f_GHAIN:
	    tempc = a_m_GHAIN;
	    break;
	case a_f_FEH:
	    tempc = a_m_FEH;
	    break;
	case a_f_QAF:
	    tempc = a_m_QAF;
	    break;
	case a_f_KAF:
	    tempc = a_m_KAF;
	    break;
	case a_f_LAM:
	    tempc = a_m_LAM;
	    break;
	case a_f_MEEM:
	    tempc = a_m_MEEM;
	    break;
	case a_f_NOON:
	    tempc = a_m_NOON;
	    break;
	case a_f_HEH:
	    tempc = a_m_HEH;
	    break;
	case a_f_YEH:
	    tempc = a_m_YEH;
	    break;
	    /* NOTE: these encodings are multi-positional, no ?
		case a_f_LAM_ALEF_MADDA_ABOVE:
		case a_f_LAM_ALEF_HAMZA_ABOVE:
		case a_f_LAM_ALEF_HAMZA_BELOW:
		case a_f_LAM_ALEF:
		*/
	default:
	    tempc = 0;
    }

    return tempc;
}


/*
 * Change shape - from Combination (2 char) to an Isolated
 */
    static int
chg_c_laa2i(hid_c)
    int hid_c;
{
    int tempc;

    switch (hid_c)
    {
	case a_ALEF_MADDA:
	    tempc = a_s_LAM_ALEF_MADDA_ABOVE;
	    break;
	case a_ALEF_HAMZA_ABOVE:
	    tempc = a_s_LAM_ALEF_HAMZA_ABOVE;
	    break;
	case a_ALEF_HAMZA_BELOW:
	    tempc = a_s_LAM_ALEF_HAMZA_BELOW;
	    break;
	case a_ALEF:
	    tempc = a_s_LAM_ALEF;
	    break;
	default:
	    tempc = 0;
    }

    return tempc;
}


/*
 * Change shape - from Combination-Isolated to Final
 */
    static int
chg_c_laa2f(hid_c)
    int hid_c;
{
    int tempc;

    switch (hid_c)
    {
	case a_ALEF_MADDA:
	    tempc = a_f_LAM_ALEF_MADDA_ABOVE;
	    break;
	case a_ALEF_HAMZA_ABOVE:
	    tempc = a_f_LAM_ALEF_HAMZA_ABOVE;
	    break;
	case a_ALEF_HAMZA_BELOW:
	    tempc = a_f_LAM_ALEF_HAMZA_BELOW;
	    break;
	case a_ALEF:
	    tempc = a_f_LAM_ALEF;
	    break;
	default:
	    tempc = 0;
    }

    return tempc;
}

/*
 * Do "half-shaping" on character "c".  Return zero if no shaping.
 */
    static int
half_shape(c)
    int		c;
{
    if (A_is_a(c))
	return chg_c_a2i(c);
    if (A_is_valid(c) && A_is_f(c))
	return chg_c_f2m(c);
    return 0;
}

/*
 * Do Arabic shaping on character "c".  Returns the shaped character.
 * out:    "ccp" points to the first byte of the character to be shaped.
 * in/out: "c1p" points to the first composing char for "c".
 * in:     "prev_c"  is the previous character (not shaped)
 * in:     "prev_c1" is the first composing char for the previous char
 *		     (not shaped)
 * in:     "next_c"  is the next character (not shaped).
 */
    int
arabic_shape(c, ccp, c1p, prev_c, prev_c1, next_c)
    int		c;
    int		*ccp;
    int		*c1p;
    int		prev_c;
    int		prev_c1;
    int		next_c;
{
    int		curr_c;
    int		shape_c;
    int		curr_laa;
    int		prev_laa;

    /* Deal only with Arabic character, pass back all others */
    if (!A_is_ok(c))
	return c;

    /* half-shape current and previous character */
    shape_c = half_shape(prev_c);

    /* Save away current character */
    curr_c = c;

    curr_laa = A_firstc_laa(c, *c1p);
    prev_laa = A_firstc_laa(prev_c, prev_c1);

    if (curr_laa)
    {
	if (A_is_valid(prev_c) && !A_is_f(shape_c)
					 && !A_is_s(shape_c) && !prev_laa)
	    curr_c = chg_c_laa2f(curr_laa);
	else
	    curr_c = chg_c_laa2i(curr_laa);

	/* Remove the composing character */
	*c1p = 0;
    }
    else if (!A_is_valid(prev_c) && A_is_valid(next_c))
	curr_c = chg_c_a2i(c);
    else if (!shape_c || A_is_f(shape_c) || A_is_s(shape_c) || prev_laa)
	curr_c = A_is_valid(next_c) ? chg_c_a2i(c) : chg_c_a2s(c);
    else if (A_is_valid(next_c))
	curr_c = A_is_iso(c) ? chg_c_a2m(c) : chg_c_i2m(c);
    else if (A_is_valid(prev_c))
	curr_c = chg_c_a2f(c);
    else
	curr_c = chg_c_a2s(c);

    /* Sanity check -- curr_c should, in the future, never be 0.
     * We should, in the future, insert a fatal error here. */
    if (curr_c == NUL)
	curr_c = c;

    if (curr_c != c && ccp != NULL)
    {
	char_u buf[MB_MAXBYTES];

	/* Update the first byte of the character. */
	(*mb_char2bytes)(curr_c, buf);
	*ccp = buf[0];
    }

    /* Return the shaped character */
    return curr_c;
}


/*
 * A_firstc_laa returns first character of LAA combination if it exists
 */
    static int
A_firstc_laa(c, c1)
    int c;	/* base character */
    int c1;	/* first composing character */
{
    if (c1 != NUL && c == a_LAM && !A_is_harakat(c1))
	return c1;
    return 0;
}


/*
 * A_is_harakat returns TRUE if 'c' is an Arabic Harakat character
 *		(harakat/tanween)
 */
    static int
A_is_harakat(c)
    int c;
{
    return (c >= a_FATHATAN && c <= a_SUKUN);
}


/*
 * A_is_iso returns TRUE if 'c' is an Arabic ISO-8859-6 character
 *		(alphabet/number/punctuation)
 */
    static int
A_is_iso(c)
    int c;
{
    return ((c >= a_HAMZA && c <= a_GHAIN)
	    || (c >= a_TATWEEL && c <= a_HAMZA_BELOW)
	    || c == a_MINI_ALEF);
}


/*
 * A_is_formb returns TRUE if 'c' is an Arabic 10646-1 FormB character
 *		(alphabet/number/punctuation)
 */
    static int
A_is_formb(c)
    int c;
{
    return ((c >= a_s_FATHATAN && c <= a_s_DAMMATAN)
	    || c == a_s_KASRATAN
	    || (c >= a_s_FATHA && c <= a_f_LAM_ALEF)
	    || c == a_BYTE_ORDER_MARK);
}


/*
 * A_is_ok returns TRUE if 'c' is an Arabic 10646 (8859-6 or Form-B)
 */
    static int
A_is_ok(c)
    int c;
{
    return (A_is_iso(c) || A_is_formb(c));
}


/*
 * A_is_valid returns TRUE if 'c' is an Arabic 10646 (8859-6 or Form-B)
 *		with some exceptions/exclusions
 */
    static int
A_is_valid(c)
    int c;
{
    return (A_is_ok(c) && !A_is_special(c));
}


/*
 * A_is_special returns TRUE if 'c' is not a special Arabic character.
 *		Specials don't adhere to most of the rules.
 */
    static int
A_is_special(c)
    int c;
{
    return (c == a_HAMZA || c == a_s_HAMZA);
}