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ushape.cpp (63965B)


      1 // © 2016 and later: Unicode, Inc. and others.
      2 // License & terms of use: http://www.unicode.org/copyright.html
      3 /*
      4 ******************************************************************************
      5 *
      6 *   Copyright (C) 2000-2016, International Business Machines
      7 *   Corporation and others.  All Rights Reserved.
      8 *
      9 ******************************************************************************
     10 *   file name:  ushape.cpp
     11 *   encoding:   UTF-8
     12 *   tab size:   8 (not used)
     13 *   indentation:4
     14 *
     15 *   created on: 2000jun29
     16 *   created by: Markus W. Scherer
     17 *
     18 *   Arabic letter shaping implemented by Ayman Roshdy
     19 */
     20 
     21 #include "unicode/utypes.h"
     22 #include "unicode/uchar.h"
     23 #include "unicode/ustring.h"
     24 #include "unicode/ushape.h"
     25 #include "cmemory.h"
     26 #include "putilimp.h"
     27 #include "ustr_imp.h"
     28 #include "ubidi_props.h"
     29 #include "uassert.h"
     30 
     31 #include <limits>
     32 /*
     33 * This implementation is designed for 16-bit Unicode strings.
     34 * The main assumption is that the Arabic characters and their
     35 * presentation forms each fit into a single char16_t.
     36 * With UTF-8, they occupy 2 or 3 bytes, and more than the ASCII
     37 * characters.
     38 */
     39 
     40 /*
     41 * ### TODO in general for letter shaping:
     42 * - the letter shaping code is UTF-16-unaware; needs update
     43 *   + especially invertBuffer()?!
     44 * - needs to handle the "Arabic Tail" that is used in some legacy codepages
     45 *   as a glyph fragment of wide-glyph letters
     46 *   + IBM Unicode conversion tables map it to U+200B (ZWSP)
     47 *   + IBM Egypt has proposed to encode the tail in Unicode among Arabic Presentation Forms
     48 *   + Unicode 3.2 added U+FE73 ARABIC TAIL FRAGMENT
     49 */
     50 
     51 /* definitions for Arabic letter shaping ------------------------------------ */
     52 
     53 #define IRRELEVANT 4
     54 #define LAMTYPE    16
     55 #define ALEFTYPE   32
     56 #define LINKR      1
     57 #define LINKL      2
     58 #define APRESENT   8
     59 #define SHADDA     64
     60 #define CSHADDA    128
     61 #define COMBINE    (SHADDA+CSHADDA)
     62 
     63 #define HAMZAFE_CHAR       0xfe80
     64 #define HAMZA06_CHAR       0x0621
     65 #define YEH_HAMZA_CHAR     0x0626
     66 #define YEH_HAMZAFE_CHAR   0xFE89
     67 #define LAMALEF_SPACE_SUB  0xFFFF
     68 #define TASHKEEL_SPACE_SUB 0xFFFE
     69 #define NEW_TAIL_CHAR      0xFE73
     70 #define OLD_TAIL_CHAR      0x200B
     71 #define LAM_CHAR           0x0644
     72 #define SPACE_CHAR         0x0020
     73 #define SHADDA_CHAR        0xFE7C
     74 #define TATWEEL_CHAR       0x0640
     75 #define SHADDA_TATWEEL_CHAR  0xFE7D
     76 #define SHADDA06_CHAR      0x0651
     77 
     78 #define SHAPE_MODE   0
     79 #define DESHAPE_MODE 1
     80 
     81 struct uShapeVariables {
     82     char16_t tailChar;
     83     uint32_t uShapeLamalefBegin;
     84     uint32_t uShapeLamalefEnd;
     85     uint32_t uShapeTashkeelBegin;
     86     uint32_t uShapeTashkeelEnd;
     87     int spacesRelativeToTextBeginEnd;
     88 };
     89 
     90 static const uint8_t tailFamilyIsolatedFinal[] = {
     91    /* FEB1 */ 1,
     92    /* FEB2 */ 1,
     93    /* FEB3 */ 0,
     94    /* FEB4 */ 0,
     95    /* FEB5 */ 1,
     96    /* FEB6 */ 1,
     97    /* FEB7 */ 0,
     98    /* FEB8 */ 0,
     99    /* FEB9 */ 1,
    100    /* FEBA */ 1,
    101    /* FEBB */ 0,
    102    /* FEBC */ 0,
    103    /* FEBD */ 1,
    104    /* FEBE */ 1
    105 };
    106 
    107 static const uint8_t tashkeelMedial[] = {
    108    /* FE70 */ 0,
    109    /* FE71 */ 1,
    110    /* FE72 */ 0,
    111    /* FE73 */ 0,
    112    /* FE74 */ 0,
    113    /* FE75 */ 0,
    114    /* FE76 */ 0,
    115    /* FE77 */ 1,
    116    /* FE78 */ 0,
    117    /* FE79 */ 1,
    118    /* FE7A */ 0,
    119    /* FE7B */ 1,
    120    /* FE7C */ 0,
    121    /* FE7D */ 1,
    122    /* FE7E */ 0,
    123    /* FE7F */ 1
    124 };
    125 
    126 static const char16_t yehHamzaToYeh[] =
    127 {
    128 /* isolated*/ 0xFEEF,
    129 /* final   */ 0xFEF0
    130 };
    131 
    132 static const uint8_t IrrelevantPos[] = {
    133    0x0, 0x2, 0x4, 0x6,
    134    0x8, 0xA, 0xC, 0xE
    135 };
    136 
    137 
    138 static const char16_t convertLamAlef[] =
    139 {
    140 /*FEF5*/    0x0622,
    141 /*FEF6*/    0x0622,
    142 /*FEF7*/    0x0623,
    143 /*FEF8*/    0x0623,
    144 /*FEF9*/    0x0625,
    145 /*FEFA*/    0x0625,
    146 /*FEFB*/    0x0627,
    147 /*FEFC*/    0x0627
    148 };
    149 
    150 static const char16_t araLink[178]=
    151 {
    152  1           + 32 + 256 * 0x11,/*0x0622*/
    153  1           + 32 + 256 * 0x13,/*0x0623*/
    154  1                + 256 * 0x15,/*0x0624*/
    155  1           + 32 + 256 * 0x17,/*0x0625*/
    156  1 + 2            + 256 * 0x19,/*0x0626*/
    157  1           + 32 + 256 * 0x1D,/*0x0627*/
    158  1 + 2            + 256 * 0x1F,/*0x0628*/
    159  1                + 256 * 0x23,/*0x0629*/
    160  1 + 2            + 256 * 0x25,/*0x062A*/
    161  1 + 2            + 256 * 0x29,/*0x062B*/
    162  1 + 2            + 256 * 0x2D,/*0x062C*/
    163  1 + 2            + 256 * 0x31,/*0x062D*/
    164  1 + 2            + 256 * 0x35,/*0x062E*/
    165  1                + 256 * 0x39,/*0x062F*/
    166  1                + 256 * 0x3B,/*0x0630*/
    167  1                + 256 * 0x3D,/*0x0631*/
    168  1                + 256 * 0x3F,/*0x0632*/
    169  1 + 2            + 256 * 0x41,/*0x0633*/
    170  1 + 2            + 256 * 0x45,/*0x0634*/
    171  1 + 2            + 256 * 0x49,/*0x0635*/
    172  1 + 2            + 256 * 0x4D,/*0x0636*/
    173  1 + 2            + 256 * 0x51,/*0x0637*/
    174  1 + 2            + 256 * 0x55,/*0x0638*/
    175  1 + 2            + 256 * 0x59,/*0x0639*/
    176  1 + 2            + 256 * 0x5D,/*0x063A*/
    177  0, 0, 0, 0, 0,                /*0x063B-0x063F*/
    178  1 + 2,                        /*0x0640*/
    179  1 + 2            + 256 * 0x61,/*0x0641*/
    180  1 + 2            + 256 * 0x65,/*0x0642*/
    181  1 + 2            + 256 * 0x69,/*0x0643*/
    182  1 + 2       + 16 + 256 * 0x6D,/*0x0644*/
    183  1 + 2            + 256 * 0x71,/*0x0645*/
    184  1 + 2            + 256 * 0x75,/*0x0646*/
    185  1 + 2            + 256 * 0x79,/*0x0647*/
    186  1                + 256 * 0x7D,/*0x0648*/
    187  1                + 256 * 0x7F,/*0x0649*/
    188  1 + 2            + 256 * 0x81,/*0x064A*/
    189         4         + 256 * 1,   /*0x064B*/
    190         4 + 128   + 256 * 1,   /*0x064C*/
    191         4 + 128   + 256 * 1,   /*0x064D*/
    192         4 + 128   + 256 * 1,   /*0x064E*/
    193         4 + 128   + 256 * 1,   /*0x064F*/
    194         4 + 128   + 256 * 1,   /*0x0650*/
    195         4 + 64    + 256 * 3,   /*0x0651*/
    196         4         + 256 * 1,   /*0x0652*/
    197         4         + 256 * 7,   /*0x0653*/
    198         4         + 256 * 8,   /*0x0654*/
    199         4         + 256 * 8,   /*0x0655*/
    200         4         + 256 * 1,   /*0x0656*/
    201  0, 0, 0, 0, 0,                /*0x0657-0x065B*/
    202  1                + 256 * 0x85,/*0x065C*/
    203  1                + 256 * 0x87,/*0x065D*/
    204  1                + 256 * 0x89,/*0x065E*/
    205  1                + 256 * 0x8B,/*0x065F*/
    206  0, 0, 0, 0, 0,                /*0x0660-0x0664*/
    207  0, 0, 0, 0, 0,                /*0x0665-0x0669*/
    208  0, 0, 0, 0, 0, 0,             /*0x066A-0x066F*/
    209         4         + 256 * 6,   /*0x0670*/
    210  1        + 8     + 256 * 0x00,/*0x0671*/
    211  1            + 32,            /*0x0672*/
    212  1            + 32,            /*0x0673*/
    213  0,                            /*0x0674*/
    214  1            + 32,            /*0x0675*/
    215  1, 1,                         /*0x0676-0x0677*/
    216  1 + 2,                        /*0x0678*/
    217  1 + 2 + 8        + 256 * 0x16,/*0x0679*/
    218  1 + 2 + 8        + 256 * 0x0E,/*0x067A*/
    219  1 + 2 + 8        + 256 * 0x02,/*0x067B*/
    220  1+2, 1+2,                     /*0x67C-0x067D*/
    221  1+2+8+256 * 0x06, 1+2, 1+2, 1+2, 1+2, 1+2, /*0x067E-0x0683*/
    222  1+2, 1+2, 1+2+8+256 * 0x2A, 1+2,           /*0x0684-0x0687*/
    223  1     + 8        + 256 * 0x38,/*0x0688*/
    224  1, 1, 1,                      /*0x0689-0x068B*/
    225  1     + 8        + 256 * 0x34,/*0x068C*/
    226  1     + 8        + 256 * 0x32,/*0x068D*/
    227  1     + 8        + 256 * 0x36,/*0x068E*/
    228  1, 1,                         /*0x068F-0x0690*/
    229  1     + 8        + 256 * 0x3C,/*0x0691*/
    230  1, 1, 1, 1, 1, 1, 1+8+256 * 0x3A, 1,       /*0x0692-0x0699*/
    231  1+2, 1+2, 1+2, 1+2, 1+2, 1+2, /*0x069A-0x06A3*/
    232  1+2, 1+2, 1+2, 1+2,           /*0x069A-0x06A3*/
    233  1+2, 1+2, 1+2, 1+2, 1+2, 1+2+8+256 * 0x3E, /*0x06A4-0x06AD*/
    234  1+2, 1+2, 1+2, 1+2,           /*0x06A4-0x06AD*/
    235  1+2, 1+2+8+256 * 0x42, 1+2, 1+2, 1+2, 1+2, /*0x06AE-0x06B7*/
    236  1+2, 1+2, 1+2, 1+2,           /*0x06AE-0x06B7*/
    237  1+2, 1+2,                     /*0x06B8-0x06B9*/
    238  1     + 8        + 256 * 0x4E,/*0x06BA*/
    239  1 + 2 + 8        + 256 * 0x50,/*0x06BB*/
    240  1+2, 1+2,                     /*0x06BC-0x06BD*/
    241  1 + 2 + 8        + 256 * 0x5A,/*0x06BE*/
    242  1+2,                          /*0x06BF*/
    243  1     + 8        + 256 * 0x54,/*0x06C0*/
    244  1 + 2 + 8        + 256 * 0x56,/*0x06C1*/
    245  1, 1, 1,                      /*0x06C2-0x06C4*/
    246  1     + 8        + 256 * 0x90,/*0x06C5*/
    247  1     + 8        + 256 * 0x89,/*0x06C6*/
    248  1     + 8        + 256 * 0x87,/*0x06C7*/
    249  1     + 8        + 256 * 0x8B,/*0x06C8*/
    250  1     + 8        + 256 * 0x92,/*0x06C9*/
    251  1,                            /*0x06CA*/
    252  1     + 8        + 256 * 0x8E,/*0x06CB*/
    253  1 + 2 + 8        + 256 * 0xAC,/*0x06CC*/
    254  1,                            /*0x06CD*/
    255  1+2, 1+2,                     /*0x06CE-0x06CF*/
    256  1 + 2 + 8        + 256 * 0x94,/*0x06D0*/
    257  1+2,                          /*0x06D1*/
    258  1     + 8        + 256 * 0x5E,/*0x06D2*/
    259  1     + 8        + 256 * 0x60 /*0x06D3*/
    260 };
    261 
    262 static const uint8_t presALink[] = {
    263 /***********0*****1*****2*****3*****4*****5*****6*****7*****8*****9*****A*****B*****C*****D*****E*****F*/
    264 /*FB5*/    0,    1,    0,    0,    0,    0,    0,    1,    2,1 + 2,    0,    0,    0,    0,    0,    0,
    265 /*FB6*/    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,
    266 /*FB7*/    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    1,    2,1 + 2,    0,    0,
    267 /*FB8*/    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    1,    0,    0,    0,    1,
    268 /*FB9*/    2,1 + 2,    0,    1,    2,1 + 2,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,
    269 /*FBA*/    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,
    270 /*FBB*/    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,
    271 /*FBC*/    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,
    272 /*FBD*/    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,
    273 /*FBE*/    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,
    274 /*FBF*/    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    1,    2,1 + 2,
    275 /*FC0*/    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,
    276 /*FC1*/    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,
    277 /*FC2*/    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,
    278 /*FC3*/    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,
    279 /*FC4*/    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,
    280 /*FC5*/    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    0,    4,    4,
    281 /*FC6*/    4,    4,    4
    282 };
    283 
    284 static const uint8_t presBLink[]=
    285 {
    286 /***********0*****1*****2*****3*****4*****5*****6*****7*****8*****9*****A*****B*****C*****D*****E*****F*/
    287 /*FE7*/1 + 2,1 + 2,1 + 2,    0,1 + 2,    0,1 + 2,1 + 2,1 + 2,1 + 2,1 + 2,1 + 2,1 + 2,1 + 2,1 + 2,1 + 2,
    288 /*FE8*/    0,    0,    1,    0,    1,    0,    1,    0,    1,    0,    1,    2,1 + 2,    0,    1,    0,
    289 /*FE9*/    1,    2,1 + 2,    0,    1,    0,    1,    2,1 + 2,    0,    1,    2,1 + 2,    0,    1,    2,
    290 /*FEA*/1 + 2,    0,    1,    2,1 + 2,    0,    1,    2,1 + 2,    0,    1,    0,    1,    0,    1,    0,
    291 /*FEB*/    1,    0,    1,    2,1 + 2,    0,    1,    2,1 + 2,    0,    1,    2,1 + 2,    0,    1,    2,
    292 /*FEC*/1 + 2,    0,    1,    2,1 + 2,    0,    1,    2,1 + 2,    0,    1,    2,1 + 2,    0,    1,    2,
    293 /*FED*/1 + 2,    0,    1,    2,1 + 2,    0,    1,    2,1 + 2,    0,    1,    2,1 + 2,    0,    1,    2,
    294 /*FEE*/1 + 2,    0,    1,    2,1 + 2,    0,    1,    2,1 + 2,    0,    1,    2,1 + 2,    0,    1,    0,
    295 /*FEF*/    1,    0,    1,    2,1 + 2,    0,    1,    0,    1,    0,    1,    0,    1,    0,    0,    0
    296 };
    297 
    298 static const char16_t convertFBto06[] =
    299 {
    300 /***********0******1******2******3******4******5******6******7******8******9******A******B******C******D******E******F***/
    301 /*FB5*/   0x671, 0x671, 0x67B, 0x67B, 0x67B, 0x67B, 0x67E, 0x67E, 0x67E, 0x67E,     0,     0,     0,     0, 0x67A, 0x67A,
    302 /*FB6*/   0x67A, 0x67A,     0,     0,     0,     0, 0x679, 0x679, 0x679, 0x679,     0,     0,     0,     0,     0,     0,
    303 /*FB7*/       0,     0,     0,     0,     0,     0,     0,     0,     0,     0, 0x686, 0x686, 0x686, 0x686,     0,     0,
    304 /*FB8*/       0,     0, 0x68D, 0x68D, 0x68C, 0x68C, 0x68E, 0x68E, 0x688, 0x688, 0x698, 0x698, 0x691, 0x691, 0x6A9, 0x6A9,
    305 /*FB9*/   0x6A9, 0x6A9, 0x6AF, 0x6AF, 0x6AF, 0x6AF,     0,     0,     0,     0,     0,     0,     0,     0, 0x6BA, 0x6BA,
    306 /*FBA*/   0x6BB, 0x6BB, 0x6BB, 0x6BB, 0x6C0, 0x6C0, 0x6C1, 0x6C1, 0x6C1, 0x6C1, 0x6BE, 0x6BE, 0x6BE, 0x6BE, 0x6d2, 0x6D2,
    307 /*FBB*/   0x6D3, 0x6D3,     0,     0,     0,     0,     0,     0,     0,     0,     0,     0,     0,     0,     0,     0,
    308 /*FBC*/       0,     0,     0,     0,     0,     0,     0,     0,     0,     0,     0,     0,     0,     0,     0,     0,
    309 /*FBD*/       0,     0,     0,     0,     0,     0,     0, 0x6C7, 0x6C7, 0x6C6, 0x6C6, 0x6C8, 0x6C8,     0, 0x6CB, 0x6CB,
    310 /*FBE*/   0x6C5, 0x6C5, 0x6C9, 0x6C9, 0x6D0, 0x6D0, 0x6D0, 0x6D0,     0,     0,     0,     0,     0,     0,     0,     0,
    311 /*FBF*/       0,     0,     0,     0,     0,     0,     0,     0,     0,     0,     0,     0, 0x6CC, 0x6CC, 0x6CC, 0x6CC
    312 };
    313 
    314 static const char16_t convertFEto06[] =
    315 {
    316 /***********0******1******2******3******4******5******6******7******8******9******A******B******C******D******E******F***/
    317 /*FE7*/   0x64B, 0x64B, 0x64C, 0x64C, 0x64D, 0x64D, 0x64E, 0x64E, 0x64F, 0x64F, 0x650, 0x650, 0x651, 0x651, 0x652, 0x652,
    318 /*FE8*/   0x621, 0x622, 0x622, 0x623, 0x623, 0x624, 0x624, 0x625, 0x625, 0x626, 0x626, 0x626, 0x626, 0x627, 0x627, 0x628,
    319 /*FE9*/   0x628, 0x628, 0x628, 0x629, 0x629, 0x62A, 0x62A, 0x62A, 0x62A, 0x62B, 0x62B, 0x62B, 0x62B, 0x62C, 0x62C, 0x62C,
    320 /*FEA*/   0x62C, 0x62D, 0x62D, 0x62D, 0x62D, 0x62E, 0x62E, 0x62E, 0x62E, 0x62F, 0x62F, 0x630, 0x630, 0x631, 0x631, 0x632,
    321 /*FEB*/   0x632, 0x633, 0x633, 0x633, 0x633, 0x634, 0x634, 0x634, 0x634, 0x635, 0x635, 0x635, 0x635, 0x636, 0x636, 0x636,
    322 /*FEC*/   0x636, 0x637, 0x637, 0x637, 0x637, 0x638, 0x638, 0x638, 0x638, 0x639, 0x639, 0x639, 0x639, 0x63A, 0x63A, 0x63A,
    323 /*FED*/   0x63A, 0x641, 0x641, 0x641, 0x641, 0x642, 0x642, 0x642, 0x642, 0x643, 0x643, 0x643, 0x643, 0x644, 0x644, 0x644,
    324 /*FEE*/   0x644, 0x645, 0x645, 0x645, 0x645, 0x646, 0x646, 0x646, 0x646, 0x647, 0x647, 0x647, 0x647, 0x648, 0x648, 0x649,
    325 /*FEF*/   0x649, 0x64A, 0x64A, 0x64A, 0x64A, 0x65C, 0x65C, 0x65D, 0x65D, 0x65E, 0x65E, 0x65F, 0x65F
    326 };
    327 
    328 static const uint8_t shapeTable[4][4][4]=
    329 {
    330  { {0,0,0,0}, {0,0,0,0}, {0,1,0,3}, {0,1,0,1} },
    331  { {0,0,2,2}, {0,0,1,2}, {0,1,1,2}, {0,1,1,3} },
    332  { {0,0,0,0}, {0,0,0,0}, {0,1,0,3}, {0,1,0,3} },
    333  { {0,0,1,2}, {0,0,1,2}, {0,1,1,2}, {0,1,1,3} }
    334 };
    335 
    336 /*
    337 * This function shapes European digits to Arabic-Indic digits
    338 * in-place, writing over the input characters.
    339 * Since we know that we are only looking for BMP code points,
    340 * we can safely just work with code units (again, at least UTF-16).
    341 */
    342 static void
    343 _shapeToArabicDigitsWithContext(char16_t *s, int32_t length,
    344                                char16_t digitBase,
    345                                UBool isLogical, UBool lastStrongWasAL) {
    346    int32_t i;
    347    char16_t c;
    348 
    349    digitBase-=0x30;
    350 
    351    /* the iteration direction depends on the type of input */
    352    if(isLogical) {
    353        for(i=0; i<length; ++i) {
    354            c=s[i];
    355            switch(ubidi_getClass(c)) {
    356            case U_LEFT_TO_RIGHT: /* L */
    357            case U_RIGHT_TO_LEFT: /* R */
    358                lastStrongWasAL=false;
    359                break;
    360            case U_RIGHT_TO_LEFT_ARABIC: /* AL */
    361                lastStrongWasAL=true;
    362                break;
    363            case U_EUROPEAN_NUMBER: /* EN */
    364                if (lastStrongWasAL && static_cast<uint32_t>(c - 0x30) < 10) {
    365                    s[i] = static_cast<char16_t>(digitBase + c); /* digitBase+(c-0x30) - digitBase was modified above */
    366                }
    367                break;
    368            default :
    369                break;
    370            }
    371        }
    372    } else {
    373        for(i=length; i>0; /* pre-decrement in the body */) {
    374            c=s[--i];
    375            switch(ubidi_getClass(c)) {
    376            case U_LEFT_TO_RIGHT: /* L */
    377            case U_RIGHT_TO_LEFT: /* R */
    378                lastStrongWasAL=false;
    379                break;
    380            case U_RIGHT_TO_LEFT_ARABIC: /* AL */
    381                lastStrongWasAL=true;
    382                break;
    383            case U_EUROPEAN_NUMBER: /* EN */
    384                if (lastStrongWasAL && static_cast<uint32_t>(c - 0x30) < 10) {
    385                    s[i] = static_cast<char16_t>(digitBase + c); /* digitBase+(c-0x30) - digitBase was modified above */
    386                }
    387                break;
    388            default :
    389                break;
    390            }
    391        }
    392    }
    393 }
    394 
    395 /*
    396 *Name     : invertBuffer
    397 *Function : This function inverts the buffer, it's used
    398 *           in case the user specifies the buffer to be
    399 *           U_SHAPE_TEXT_DIRECTION_LOGICAL
    400 */
    401 static void
    402 invertBuffer(char16_t *buffer, int32_t size, uint32_t /*options*/, int32_t lowlimit, int32_t highlimit) {
    403    char16_t temp;
    404    int32_t i=0,j=0;
    405    for(i=lowlimit,j=size-highlimit-1;i<j;i++,j--) {
    406        temp = buffer[i];
    407        buffer[i] = buffer[j];
    408        buffer[j] = temp;
    409    }
    410 }
    411 
    412 /*
    413 *Name     : changeLamAlef
    414 *Function : Converts the Alef characters into an equivalent
    415 *           LamAlef location in the 0x06xx Range, this is an
    416 *           intermediate stage in the operation of the program
    417 *           later it'll be converted into the 0xFExx LamAlefs
    418 *           in the shaping function.
    419 */
    420 static inline char16_t
    421 changeLamAlef(char16_t ch) {
    422    switch(ch) {
    423    case 0x0622 :
    424        return 0x065C;
    425    case 0x0623 :
    426        return 0x065D;
    427    case 0x0625 :
    428        return 0x065E;
    429    case 0x0627 :
    430        return 0x065F;
    431    }
    432    return 0;
    433 }
    434 
    435 /*
    436 *Name     : getLink
    437 *Function : Resolves the link between the characters as
    438 *           Arabic characters have four forms :
    439 *           Isolated, Initial, Middle and Final Form
    440 */
    441 static char16_t
    442 getLink(char16_t ch) {
    443    if(ch >= 0x0622 && ch <= 0x06D3) {
    444        return(araLink[ch-0x0622]);
    445    } else if(ch == 0x200D) {
    446        return(3);
    447    } else if(ch >= 0x206D && ch <= 0x206F) {
    448        return(4);
    449    }else if(ch >= 0xFB50 && ch <= 0xFC62) {
    450        return(presALink[ch-0xFB50]);
    451    } else if(ch >= 0xFE70 && ch <= 0xFEFC) {
    452        return(presBLink[ch-0xFE70]);
    453    }else {
    454        return(0);
    455    }
    456 }
    457 
    458 /*
    459 *Name     : countSpaces
    460 *Function : Counts the number of spaces
    461 *           at each end of the logical buffer
    462 */
    463 static void
    464 countSpaces(char16_t *dest, int32_t size, uint32_t /*options*/, int32_t *spacesCountl, int32_t *spacesCountr) {
    465    int32_t i = 0;
    466    int32_t countl = 0,countr = 0;
    467    while((dest[i] == SPACE_CHAR) && (countl < size)) {
    468       countl++;
    469       i++;
    470    }
    471    if (countl < size) {  /* the entire buffer is not all space */
    472        while(dest[size-1] == SPACE_CHAR) {
    473            countr++;
    474            size--;
    475        }
    476    }
    477    *spacesCountl = countl;
    478    *spacesCountr = countr;
    479 }
    480 
    481 /*
    482 *Name     : isTashkeelChar
    483 *Function : Returns 1 for Tashkeel characters in 06 range else return 0
    484 */
    485 static inline int32_t
    486 isTashkeelChar(char16_t ch) {
    487    return static_cast<int32_t>(ch >= 0x064B && ch <= 0x0652);
    488 }
    489 
    490 /*
    491 *Name     : isTashkeelCharFE
    492 *Function : Returns 1 for Tashkeel characters in FE range else return 0
    493 */
    494 static inline int32_t
    495 isTashkeelCharFE(char16_t ch) {
    496    return static_cast<int32_t>(ch >= 0xFE70 && ch <= 0xFE7F);
    497 }
    498 
    499 /*
    500 *Name     : isAlefChar
    501 *Function : Returns 1 for Alef characters else return 0
    502 */
    503 static inline int32_t
    504 isAlefChar(char16_t ch) {
    505    return static_cast<int32_t>(ch == 0x0622 || ch == 0x0623 || ch == 0x0625 || ch == 0x0627);
    506 }
    507 
    508 /*
    509 *Name     : isLamAlefChar
    510 *Function : Returns 1 for LamAlef characters else return 0
    511 */
    512 static inline int32_t
    513 isLamAlefChar(char16_t ch) {
    514    return static_cast<int32_t>(ch >= 0xFEF5 && ch <= 0xFEFC);
    515 }
    516 
    517 /*BIDI
    518 *Name     : isTailChar
    519 *Function : returns 1 if the character matches one of the tail characters (0xfe73 or 0x200b) otherwise returns 0
    520 */
    521 
    522 static inline int32_t
    523 isTailChar(char16_t ch) {
    524    if(ch == OLD_TAIL_CHAR || ch == NEW_TAIL_CHAR){
    525            return 1;
    526    }else{
    527            return 0;
    528    }
    529 }
    530 
    531 /*BIDI
    532 *Name     : isSeenTailFamilyChar
    533 *Function : returns 1 if the character is a seen family isolated character
    534 *           in the FE range otherwise returns 0
    535 */
    536 
    537 static inline int32_t
    538 isSeenTailFamilyChar(char16_t ch) {
    539    if(ch >= 0xfeb1 && ch < 0xfebf){
    540            return tailFamilyIsolatedFinal [ch - 0xFEB1];
    541    }else{
    542            return 0;
    543    }
    544 }
    545 
    546 /* Name     : isSeenFamilyChar
    547  * Function : returns 1 if the character is a seen family character in the Unicode
    548  *            06 range otherwise returns 0
    549 */
    550 
    551 static inline int32_t
    552 isSeenFamilyChar(char16_t  ch){
    553    if(ch >= 0x633 && ch <= 0x636){
    554        return 1;
    555    }else {
    556        return 0;
    557    }
    558 }
    559 
    560 /*Start of BIDI*/
    561 /*
    562 *Name     : isAlefMaksouraChar
    563 *Function : returns 1 if the character is a Alef Maksoura Final or isolated
    564 *           otherwise returns 0
    565 */
    566 static inline int32_t
    567 isAlefMaksouraChar(char16_t ch) {
    568    return static_cast<int32_t>(ch == 0xFEEF || ch == 0xFEF0 || ch == 0x0649);
    569 }
    570 
    571 /*
    572 * Name     : isYehHamzaChar
    573 * Function : returns 1 if the character is a yehHamza isolated or yehhamza
    574 *            final is found otherwise returns 0
    575 */
    576 static inline int32_t
    577 isYehHamzaChar(char16_t ch) {
    578    if((ch==0xFE89)||(ch==0xFE8A)){
    579        return 1;
    580    }else{
    581        return 0;
    582    }
    583 }
    584 
    585 /*
    586 * Name: isTashkeelOnTatweelChar
    587 * Function: Checks if the Tashkeel Character is on Tatweel or not,if the
    588 *           Tashkeel on tatweel (FE range), it returns 1 else if the
    589 *           Tashkeel with shadda on tatweel (FC range)return 2 otherwise
    590 *           returns 0
    591 */
    592 static inline int32_t
    593 isTashkeelOnTatweelChar(char16_t ch){
    594    if(ch >= 0xfe70 && ch <= 0xfe7f && ch != NEW_TAIL_CHAR && ch != 0xFE75 && ch != SHADDA_TATWEEL_CHAR)
    595    {
    596        return tashkeelMedial [ch - 0xFE70];
    597    }else if( (ch >= 0xfcf2 && ch <= 0xfcf4) || (ch == SHADDA_TATWEEL_CHAR)) {
    598        return 2;
    599    }else{
    600        return 0;
    601    }
    602 }
    603 
    604 /*
    605 * Name: isIsolatedTashkeelChar
    606 * Function: Checks if the Tashkeel Character is in the isolated form
    607 *           (i.e. Unicode FE range) returns 1 else if the Tashkeel
    608 *           with shadda is in the isolated form (i.e. Unicode FC range)
    609 *           returns 2 otherwise returns 0
    610 */
    611 static inline int32_t
    612 isIsolatedTashkeelChar(char16_t ch){
    613    if(ch >= 0xfe70 && ch <= 0xfe7f && ch != NEW_TAIL_CHAR && ch != 0xFE75){
    614        return (1 - tashkeelMedial [ch - 0xFE70]);
    615    }else if(ch >= 0xfc5e && ch <= 0xfc63){
    616        return 1;
    617    }else{
    618        return 0;
    619    }
    620 }
    621 
    622 
    623 
    624 
    625 /*
    626 *Name     : calculateSize
    627 *Function : This function calculates the destSize to be used in preflighting
    628 *           when the destSize is equal to 0
    629 *           It is used also to calculate the new destsize in case the
    630 *           destination buffer will be resized.
    631 */
    632 
    633 static int32_t
    634 calculateSize(const char16_t *source, int32_t sourceLength,
    635 int32_t destSize,uint32_t options) {
    636    int32_t i = 0;
    637 
    638    int lamAlefOption = 0;
    639    int tashkeelOption = 0;
    640 
    641    destSize = sourceLength;
    642 
    643    if (((options&U_SHAPE_LETTERS_MASK) == U_SHAPE_LETTERS_SHAPE ||
    644        ((options&U_SHAPE_LETTERS_MASK) == U_SHAPE_LETTERS_SHAPE_TASHKEEL_ISOLATED )) &&
    645        ((options&U_SHAPE_LAMALEF_MASK) == U_SHAPE_LAMALEF_RESIZE )){
    646            lamAlefOption = 1;
    647    }
    648    if((options&U_SHAPE_LETTERS_MASK) == U_SHAPE_LETTERS_SHAPE &&
    649       ((options&U_SHAPE_TASHKEEL_MASK) == U_SHAPE_TASHKEEL_RESIZE ) ){
    650            tashkeelOption = 1;
    651        }
    652 
    653    if(lamAlefOption || tashkeelOption){
    654        if((options&U_SHAPE_TEXT_DIRECTION_MASK)==U_SHAPE_TEXT_DIRECTION_VISUAL_LTR) {
    655            for(i=0;i<sourceLength;i++) {
    656                if( ((isAlefChar(source[i]))&& (i<(sourceLength-1)) &&(source[i+1] == LAM_CHAR)) || (isTashkeelCharFE(source[i])) ) {
    657                        destSize--;
    658                    }
    659                }
    660            }else if((options&U_SHAPE_TEXT_DIRECTION_MASK)==U_SHAPE_TEXT_DIRECTION_LOGICAL) {
    661                for(i=0;i<sourceLength;i++) {
    662                    if( ( (source[i] == LAM_CHAR) && (i<(sourceLength-1)) && (isAlefChar(source[i+1]))) || (isTashkeelCharFE(source[i])) ) {
    663                        destSize--;
    664                    }
    665                }
    666            }
    667        }
    668 
    669    if ((options&U_SHAPE_LETTERS_MASK) == U_SHAPE_LETTERS_UNSHAPE){
    670        if ( (options&U_SHAPE_LAMALEF_MASK) == U_SHAPE_LAMALEF_RESIZE){
    671            for(i=0;i<sourceLength;i++) {
    672                if(isLamAlefChar(source[i]))
    673                destSize++;
    674            }
    675        }
    676    }
    677 
    678    return destSize;
    679 }
    680 
    681 /*
    682 *Name     : handleTashkeelWithTatweel
    683 *Function : Replaces Tashkeel as following:
    684 *            Case 1 :if the Tashkeel on tatweel, replace it with Tatweel.
    685 *            Case 2 :if the Tashkeel aggregated with Shadda on Tatweel, replace
    686 *                   it with Shadda on Tatweel.
    687 *            Case 3: if the Tashkeel is isolated replace it with Space.
    688 *
    689 */
    690 static int32_t
    691 handleTashkeelWithTatweel(char16_t *dest, int32_t sourceLength,
    692             int32_t /*destSize*/, uint32_t /*options*/,
    693             UErrorCode * /*pErrorCode*/) {
    694                 int i;
    695                 for(i = 0; i < sourceLength; i++){
    696                     if((isTashkeelOnTatweelChar(dest[i]) == 1)){
    697                         dest[i] = TATWEEL_CHAR;
    698                    }else if((isTashkeelOnTatweelChar(dest[i]) == 2)){
    699                         dest[i] = SHADDA_TATWEEL_CHAR;
    700                    }else if(isIsolatedTashkeelChar(dest[i]) && dest[i] != SHADDA_CHAR){
    701                         dest[i] = SPACE_CHAR;
    702                    }
    703                 }
    704                 return sourceLength;
    705 }
    706 
    707 
    708 
    709 /*
    710 *Name     : handleGeneratedSpaces
    711 *Function : The shapeUnicode function converts Lam + Alef into LamAlef + space,
    712 *           and Tashkeel to space.
    713 *           handleGeneratedSpaces function puts these generated spaces
    714 *           according to the options the user specifies. LamAlef and Tashkeel
    715 *           spaces can be replaced at begin, at end, at near or decrease the
    716 *           buffer size.
    717 *
    718 *           There is also Auto option for LamAlef and tashkeel, which will put
    719 *           the spaces at end of the buffer (or end of text if the user used
    720 *           the option U_SHAPE_SPACES_RELATIVE_TO_TEXT_BEGIN_END).
    721 *
    722 *           If the text type was visual_LTR and the option
    723 *           U_SHAPE_SPACES_RELATIVE_TO_TEXT_BEGIN_END was selected the END
    724 *           option will place the space at the beginning of the buffer and
    725 *           BEGIN will place the space at the end of the buffer.
    726 */
    727 
    728 static int32_t
    729 handleGeneratedSpaces(char16_t *dest, int32_t sourceLength,
    730                    int32_t destSize,
    731                    uint32_t options,
    732                    UErrorCode *pErrorCode,struct uShapeVariables shapeVars ) {
    733 
    734    int32_t i = 0, j = 0;
    735    int32_t count = 0;
    736    char16_t *tempbuffer=nullptr;
    737 
    738    int lamAlefOption = 0;
    739    int tashkeelOption = 0;
    740    int shapingMode = SHAPE_MODE;
    741 
    742    if (shapingMode == 0){
    743        if ( (options&U_SHAPE_LAMALEF_MASK) == U_SHAPE_LAMALEF_RESIZE ){
    744            lamAlefOption = 1;
    745        }
    746        if ( (options&U_SHAPE_TASHKEEL_MASK) == U_SHAPE_TASHKEEL_RESIZE ){
    747            tashkeelOption = 1;
    748        }
    749    }
    750 
    751    if (static_cast<size_t>(sourceLength) + 1 > std::numeric_limits<size_t>::max() / U_SIZEOF_UCHAR) {
    752        *pErrorCode = U_INDEX_OUTOFBOUNDS_ERROR;
    753        return 0;
    754    }
    755    tempbuffer = static_cast<char16_t*>(uprv_malloc((sourceLength + 1) * U_SIZEOF_UCHAR));
    756    /* Test for nullptr */
    757    if(tempbuffer == nullptr) {
    758        *pErrorCode = U_MEMORY_ALLOCATION_ERROR;
    759        return 0;
    760    }
    761 
    762 
    763    if (lamAlefOption || tashkeelOption){
    764        uprv_memset(tempbuffer, 0, (sourceLength+1)*U_SIZEOF_UCHAR);
    765 
    766        i = j = 0; count = 0;
    767        while(i < sourceLength) {
    768            if ( (lamAlefOption && dest[i] == LAMALEF_SPACE_SUB) ||
    769               (tashkeelOption && dest[i] == TASHKEEL_SPACE_SUB) ){
    770                j--;
    771                count++;
    772            } else {
    773                tempbuffer[j] = dest[i];
    774            }
    775            i++;
    776            j++;
    777        }
    778 
    779        while(count >= 0) {
    780            tempbuffer[i] = 0x0000;
    781            i--;
    782            count--;
    783        }
    784 
    785        u_memcpy(dest, tempbuffer, sourceLength);
    786        destSize = u_strlen(dest);
    787    }
    788 
    789      lamAlefOption = 0;
    790 
    791    if (shapingMode == 0){
    792        if ( (options&U_SHAPE_LAMALEF_MASK) == U_SHAPE_LAMALEF_NEAR ){
    793            lamAlefOption = 1;
    794        }
    795    }
    796 
    797    if (lamAlefOption){
    798        /* Lam+Alef is already shaped into LamAlef + FFFF */
    799        i = 0;
    800        while(i < sourceLength) {
    801            if(lamAlefOption&&dest[i] == LAMALEF_SPACE_SUB){
    802                dest[i] = SPACE_CHAR;
    803            }
    804            i++;
    805        }
    806        destSize = sourceLength;
    807    }
    808    lamAlefOption = 0;
    809    tashkeelOption = 0;
    810 
    811    if (shapingMode == 0) {
    812        if ( ((options&U_SHAPE_LAMALEF_MASK) == shapeVars.uShapeLamalefBegin) ||
    813              (((options&U_SHAPE_LAMALEF_MASK) == U_SHAPE_LAMALEF_AUTO )
    814              && (shapeVars.spacesRelativeToTextBeginEnd==1)) ) {
    815            lamAlefOption = 1;
    816        }
    817        if ( (options&U_SHAPE_TASHKEEL_MASK) == shapeVars.uShapeTashkeelBegin ) {
    818            tashkeelOption = 1;
    819        }
    820    }
    821 
    822    if(lamAlefOption || tashkeelOption){
    823        uprv_memset(tempbuffer, 0, (sourceLength+1)*U_SIZEOF_UCHAR);
    824        
    825        i = j = sourceLength; count = 0;
    826        
    827        while(i >= 0) {
    828            if ( (lamAlefOption && dest[i] == LAMALEF_SPACE_SUB) ||
    829                 (tashkeelOption && dest[i] == TASHKEEL_SPACE_SUB) ){
    830                j++;
    831                count++;
    832            }else {
    833                tempbuffer[j] = dest[i];
    834            }
    835            i--;
    836            j--;
    837        }
    838 
    839        for(i=0 ;i < count; i++){
    840                tempbuffer[i] = SPACE_CHAR;
    841        }
    842 
    843        u_memcpy(dest, tempbuffer, sourceLength);
    844        destSize = sourceLength;
    845    }
    846 
    847 
    848 
    849    lamAlefOption = 0;
    850    tashkeelOption = 0;
    851 
    852    if (shapingMode == 0) {
    853        if ( ((options&U_SHAPE_LAMALEF_MASK) == shapeVars.uShapeLamalefEnd) ||
    854              (((options&U_SHAPE_LAMALEF_MASK) == U_SHAPE_LAMALEF_AUTO )
    855              && (shapeVars.spacesRelativeToTextBeginEnd==0)) ) {
    856            lamAlefOption = 1;
    857        }
    858        if ( (options&U_SHAPE_TASHKEEL_MASK) == shapeVars.uShapeTashkeelEnd ){
    859            tashkeelOption = 1;
    860        }
    861    }
    862 
    863    if(lamAlefOption || tashkeelOption){
    864        uprv_memset(tempbuffer, 0, (sourceLength+1)*U_SIZEOF_UCHAR);
    865 
    866        i = j = 0; count = 0;
    867        while(i < sourceLength) {
    868            if ( (lamAlefOption && dest[i] == LAMALEF_SPACE_SUB) ||
    869                 (tashkeelOption && dest[i] == TASHKEEL_SPACE_SUB) ){
    870                j--;
    871                count++;
    872            }else {
    873                tempbuffer[j] = dest[i];
    874            }
    875            i++;
    876            j++;
    877        }
    878 
    879        while(count >= 0) {
    880            tempbuffer[i] = SPACE_CHAR;
    881            i--;
    882            count--;
    883        }
    884 
    885        u_memcpy(dest, tempbuffer, sourceLength);
    886        destSize = sourceLength;
    887    }
    888 
    889 
    890    if(tempbuffer){
    891        uprv_free(tempbuffer);
    892    }
    893 
    894    return destSize;
    895 }
    896 
    897 /*
    898 *Name     :expandCompositCharAtBegin
    899 *Function :Expands the LamAlef character to Lam and Alef consuming the required
    900 *         space from beginning of the buffer. If the text type was visual_LTR
    901 *         and the option U_SHAPE_SPACES_RELATIVE_TO_TEXT_BEGIN_END was selected
    902 *         the spaces will be located at end of buffer.
    903 *         If there are no spaces to expand the LamAlef, an error
    904 *         will be set to U_NO_SPACE_AVAILABLE as defined in utypes.h
    905 */
    906 
    907 static int32_t
    908 expandCompositCharAtBegin(char16_t *dest, int32_t sourceLength, int32_t destSize,UErrorCode *pErrorCode) {
    909    int32_t      i = 0,j = 0;
    910    int32_t      countl = 0;
    911    char16_t *tempbuffer=nullptr;
    912 
    913    tempbuffer = static_cast<char16_t*>(uprv_malloc((sourceLength + 1) * U_SIZEOF_UCHAR));
    914 
    915    /* Test for nullptr */
    916    if(tempbuffer == nullptr) {
    917        *pErrorCode = U_MEMORY_ALLOCATION_ERROR;
    918        return 0;
    919    }
    920 
    921        uprv_memset(tempbuffer, 0, (sourceLength+1)*U_SIZEOF_UCHAR);
    922 
    923        i = 0;
    924        while(dest[i] == SPACE_CHAR) {
    925            countl++;
    926            i++;
    927        }
    928 
    929        i = j = sourceLength-1;
    930 
    931        while(i >= 0 && j >= 0) {
    932            if( countl>0 && isLamAlefChar(dest[i])) {
    933                tempbuffer[j] = LAM_CHAR;
    934                /* to ensure the array index is within the range */
    935                U_ASSERT(dest[i] >= 0xFEF5u
    936                    && dest[i]-0xFEF5u < UPRV_LENGTHOF(convertLamAlef));
    937                tempbuffer[j-1] = convertLamAlef[ dest[i] - 0xFEF5 ];
    938                j--;
    939                countl--;
    940            }else {
    941                 if( countl == 0 && isLamAlefChar(dest[i]) ) {
    942                     *pErrorCode=U_NO_SPACE_AVAILABLE;
    943                     }
    944                 tempbuffer[j] = dest[i];
    945            }
    946            i--;
    947            j--;
    948        }
    949        u_memcpy(dest, tempbuffer, sourceLength);
    950 
    951        uprv_free(tempbuffer);
    952 
    953        destSize = sourceLength;
    954        return destSize;
    955 }
    956 
    957 /*
    958 *Name     : expandCompositCharAtEnd
    959 *Function : Expands the LamAlef character to Lam and Alef consuming the
    960 *           required space from end of the buffer. If the text type was
    961 *           Visual LTR and the option U_SHAPE_SPACES_RELATIVE_TO_TEXT_BEGIN_END
    962 *           was used, the spaces will be consumed from begin of buffer. If
    963 *           there are no spaces to expand the LamAlef, an error
    964 *           will be set to U_NO_SPACE_AVAILABLE as defined in utypes.h
    965 */
    966 
    967 static int32_t
    968 expandCompositCharAtEnd(char16_t *dest, int32_t sourceLength, int32_t destSize,UErrorCode *pErrorCode) {
    969    int32_t      i = 0,j = 0;
    970 
    971    int32_t      countr = 0;
    972    int32_t  inpsize = sourceLength;
    973 
    974    char16_t *tempbuffer=nullptr;
    975    tempbuffer = static_cast<char16_t*>(uprv_malloc((sourceLength + 1) * U_SIZEOF_UCHAR));
    976 
    977    /* Test for nullptr */
    978    if(tempbuffer == nullptr) {
    979        *pErrorCode = U_MEMORY_ALLOCATION_ERROR;
    980         return 0;
    981    }
    982 
    983    uprv_memset(tempbuffer, 0, (sourceLength+1)*U_SIZEOF_UCHAR);
    984 
    985    while(dest[inpsize-1] == SPACE_CHAR) {
    986        countr++;
    987        inpsize--;
    988    }
    989 
    990    i = sourceLength - countr - 1;
    991    j = sourceLength - 1;
    992 
    993    while(i >= 0 && j >= 0) {
    994        if( countr>0 && isLamAlefChar(dest[i]) ) {
    995            tempbuffer[j] = LAM_CHAR;
    996            tempbuffer[j-1] = convertLamAlef[ dest[i] - 0xFEF5 ];
    997            j--;
    998            countr--;
    999        }else {
   1000            if ((countr == 0) && isLamAlefChar(dest[i]) ) {
   1001                *pErrorCode=U_NO_SPACE_AVAILABLE;
   1002            }
   1003            tempbuffer[j] = dest[i];
   1004        }
   1005        i--;
   1006        j--;
   1007    }
   1008 
   1009    if(countr > 0) {
   1010        u_memmove(tempbuffer, tempbuffer+countr, sourceLength);
   1011        if(u_strlen(tempbuffer) < sourceLength) {
   1012            for(i=sourceLength-1;i>=sourceLength-countr;i--) {
   1013                tempbuffer[i] = SPACE_CHAR;
   1014            }
   1015        }
   1016    }
   1017    u_memcpy(dest, tempbuffer, sourceLength);
   1018 
   1019    uprv_free(tempbuffer);
   1020 
   1021    destSize = sourceLength;
   1022    return destSize;
   1023 }
   1024 
   1025 /*
   1026 *Name     : expandCompositCharAtNear
   1027 *Function : Expands the LamAlef character into Lam + Alef, YehHamza character
   1028 *           into Yeh + Hamza, SeenFamily character into SeenFamily character
   1029 *           + Tail, while consuming the space next to the character.
   1030 *           If there are no spaces next to the character, an error
   1031 *           will be set to U_NO_SPACE_AVAILABLE as defined in utypes.h
   1032 */
   1033 
   1034 static int32_t
   1035 expandCompositCharAtNear(char16_t *dest, int32_t sourceLength, int32_t destSize,UErrorCode *pErrorCode,
   1036                         int yehHamzaOption, int seenTailOption, int lamAlefOption, struct uShapeVariables shapeVars) {
   1037    int32_t      i = 0;
   1038 
   1039 
   1040    char16_t lamalefChar, yehhamzaChar;
   1041 
   1042    for(i = 0 ;i<=sourceLength-1;i++) {
   1043            if (seenTailOption && isSeenTailFamilyChar(dest[i])) {
   1044                if ((i>0) && (dest[i-1] == SPACE_CHAR) ) {
   1045                    dest[i-1] = shapeVars.tailChar;
   1046                }else {
   1047                    *pErrorCode=U_NO_SPACE_AVAILABLE;
   1048                }
   1049            }else if(yehHamzaOption && (isYehHamzaChar(dest[i])) ) {
   1050                if ((i>0) && (dest[i-1] == SPACE_CHAR) ) {
   1051                    yehhamzaChar = dest[i];
   1052                    dest[i] = yehHamzaToYeh[yehhamzaChar - YEH_HAMZAFE_CHAR];
   1053                    dest[i-1] = HAMZAFE_CHAR;
   1054                }else {
   1055 
   1056                    *pErrorCode=U_NO_SPACE_AVAILABLE;
   1057                }
   1058            }else if(lamAlefOption && isLamAlefChar(dest[i+1])) {
   1059                if(dest[i] == SPACE_CHAR){
   1060                    lamalefChar = dest[i+1];
   1061                    dest[i+1] = LAM_CHAR;
   1062                    dest[i] = convertLamAlef[ lamalefChar - 0xFEF5 ];
   1063                }else {
   1064                    *pErrorCode=U_NO_SPACE_AVAILABLE;
   1065                }
   1066            }
   1067       }
   1068       destSize = sourceLength;
   1069       return destSize;
   1070 }
   1071 /*
   1072 * Name     : expandCompositChar
   1073 * Function : LamAlef, need special handling, since it expands from one
   1074 *            character into two characters while shaping or deshaping.
   1075 *            In order to expand it, near or far spaces according to the
   1076 *            options user specifies. Also buffer size can be increased.
   1077 *
   1078 *            For SeenFamily characters and YehHamza only the near option is
   1079 *            supported, while for LamAlef we can take spaces from begin, end,
   1080 *            near or even increase the buffer size.
   1081 *            There is also the Auto option for LamAlef only, which will first
   1082 *            search for a space at end, begin then near, respectively.
   1083 *            If there are no spaces to expand these characters, an error will be set to
   1084 *            U_NO_SPACE_AVAILABLE as defined in utypes.h
   1085 */
   1086 
   1087 static int32_t
   1088 expandCompositChar(char16_t *dest, int32_t sourceLength,
   1089              int32_t destSize,uint32_t options,
   1090              UErrorCode *pErrorCode, int shapingMode,struct uShapeVariables shapeVars) {
   1091 
   1092    int32_t      i = 0,j = 0;
   1093 
   1094    char16_t *tempbuffer=nullptr;
   1095    int yehHamzaOption = 0;
   1096    int seenTailOption = 0;
   1097    int lamAlefOption = 0;
   1098 
   1099    if (shapingMode == 1){
   1100        if ( (options&U_SHAPE_LAMALEF_MASK) == U_SHAPE_LAMALEF_AUTO){
   1101 
   1102            if(shapeVars.spacesRelativeToTextBeginEnd == 0) {
   1103                destSize = expandCompositCharAtEnd(dest, sourceLength, destSize, pErrorCode);
   1104 
   1105                if(*pErrorCode == U_NO_SPACE_AVAILABLE) {
   1106                    *pErrorCode = U_ZERO_ERROR;
   1107                    destSize = expandCompositCharAtBegin(dest, sourceLength, destSize, pErrorCode);
   1108                }
   1109            }else {
   1110                destSize = expandCompositCharAtBegin(dest, sourceLength, destSize, pErrorCode);
   1111 
   1112                if(*pErrorCode == U_NO_SPACE_AVAILABLE) {
   1113                    *pErrorCode = U_ZERO_ERROR;
   1114                    destSize = expandCompositCharAtEnd(dest, sourceLength, destSize, pErrorCode);
   1115                }
   1116            }
   1117 
   1118            if(*pErrorCode == U_NO_SPACE_AVAILABLE) {
   1119                *pErrorCode = U_ZERO_ERROR;
   1120                destSize = expandCompositCharAtNear(dest, sourceLength, destSize, pErrorCode, yehHamzaOption,
   1121                                                seenTailOption, 1,shapeVars);
   1122            }
   1123        }
   1124    }
   1125 
   1126    if (shapingMode == 1){
   1127        if ( (options&U_SHAPE_LAMALEF_MASK) == shapeVars.uShapeLamalefEnd){
   1128            destSize = expandCompositCharAtEnd(dest, sourceLength, destSize, pErrorCode);
   1129        }
   1130    }
   1131 
   1132    if (shapingMode == 1){
   1133        if ( (options&U_SHAPE_LAMALEF_MASK) == shapeVars.uShapeLamalefBegin){
   1134            destSize = expandCompositCharAtBegin(dest, sourceLength, destSize, pErrorCode);
   1135        }
   1136    }
   1137 
   1138    if (shapingMode == 0){
   1139         if ((options&U_SHAPE_YEHHAMZA_MASK) == U_SHAPE_YEHHAMZA_TWOCELL_NEAR){
   1140             yehHamzaOption = 1;
   1141         }
   1142         if ((options&U_SHAPE_SEEN_MASK) == U_SHAPE_SEEN_TWOCELL_NEAR){
   1143            seenTailOption = 1;
   1144         }
   1145    }
   1146    if (shapingMode == 1) {
   1147        if ( (options&U_SHAPE_LAMALEF_MASK) == U_SHAPE_LAMALEF_NEAR) {
   1148            lamAlefOption = 1;
   1149        }
   1150    }
   1151 
   1152 
   1153    if (yehHamzaOption || seenTailOption || lamAlefOption){
   1154        destSize = expandCompositCharAtNear(dest, sourceLength, destSize, pErrorCode, yehHamzaOption,
   1155                                            seenTailOption,lamAlefOption,shapeVars);
   1156    }
   1157 
   1158 
   1159    if (shapingMode == 1){
   1160        if ( (options&U_SHAPE_LAMALEF_MASK) == U_SHAPE_LAMALEF_RESIZE){
   1161            destSize = calculateSize(dest,sourceLength,destSize,options);
   1162            tempbuffer = static_cast<char16_t*>(uprv_malloc((destSize + 1) * U_SIZEOF_UCHAR));
   1163 
   1164            /* Test for nullptr */
   1165            if(tempbuffer == nullptr) {
   1166                *pErrorCode = U_MEMORY_ALLOCATION_ERROR;
   1167                return 0;
   1168            }
   1169 
   1170            uprv_memset(tempbuffer, 0, (destSize+1)*U_SIZEOF_UCHAR);
   1171 
   1172            i = j = 0;
   1173            while(i < destSize && j < destSize) {
   1174                if(isLamAlefChar(dest[i]) ) {
   1175                    tempbuffer[j] = convertLamAlef[ dest[i] - 0xFEF5 ];
   1176                    tempbuffer[j+1] = LAM_CHAR;
   1177                    j++;
   1178                }else {
   1179                    tempbuffer[j] = dest[i];
   1180                }
   1181                i++;
   1182                j++;
   1183            }
   1184 
   1185            u_memcpy(dest, tempbuffer, destSize);
   1186        }
   1187    }
   1188 
   1189    if(tempbuffer) {
   1190        uprv_free(tempbuffer);
   1191    }
   1192    return destSize;
   1193 }
   1194 
   1195 /*
   1196 *Name     : shapeUnicode
   1197 *Function : Converts an Arabic Unicode buffer in 06xx Range into a shaped
   1198 *           arabic Unicode buffer in FExx Range
   1199 */
   1200 static int32_t
   1201 shapeUnicode(char16_t *dest, int32_t sourceLength,
   1202             int32_t destSize,uint32_t options,
   1203             UErrorCode *pErrorCode,
   1204             int tashkeelFlag, struct uShapeVariables shapeVars) {
   1205 
   1206    int32_t          i, iend;
   1207    int32_t          step;
   1208    int32_t          lastPos,Nx, Nw;
   1209    unsigned int     Shape;
   1210    int32_t          lamalef_found = 0;
   1211    int32_t seenfamFound = 0, yehhamzaFound =0, tashkeelFound  = 0;
   1212    char16_t         prevLink = 0, lastLink = 0, currLink, nextLink = 0;
   1213    char16_t         wLamalef;
   1214 
   1215    /*
   1216     * Converts the input buffer from FExx Range into 06xx Range
   1217     * to make sure that all characters are in the 06xx range
   1218     * even the lamalef is converted to the special region in
   1219     * the 06xx range
   1220     */
   1221    if ((options & U_SHAPE_PRESERVE_PRESENTATION_MASK)  == U_SHAPE_PRESERVE_PRESENTATION_NOOP) {
   1222        for (i = 0; i < sourceLength; i++) {
   1223            char16_t inputChar  = dest[i];
   1224            if ( (inputChar >= 0xFB50) && (inputChar <= 0xFBFF)) {
   1225                char16_t c = convertFBto06 [ (inputChar - 0xFB50) ];
   1226                if (c != 0)
   1227                    dest[i] = c;
   1228            } else if ( (inputChar >= 0xFE70) && (inputChar <= 0xFEFC)) {
   1229                dest[i] = convertFEto06 [ (inputChar - 0xFE70) ] ;
   1230            } else {
   1231                dest[i] = inputChar ;
   1232            }
   1233        }
   1234    }
   1235 
   1236 
   1237    /* sets the index to the end of the buffer, together with the step point to -1 */
   1238    i = sourceLength - 1;
   1239    iend = -1;
   1240    step = -1;
   1241 
   1242    /*
   1243     * This function resolves the link between the characters .
   1244     * Arabic characters have four forms :
   1245     * Isolated Form, Initial Form, Middle Form and Final Form
   1246     */
   1247    currLink = getLink(dest[i]);
   1248 
   1249    lastPos = i;
   1250    Nx = -2, Nw = 0;
   1251 
   1252    while (i != iend) {
   1253        /* If high byte of currLink > 0 then more than one shape */
   1254        if ((currLink & 0xFF00) > 0 || (getLink(dest[i]) & IRRELEVANT) != 0) {
   1255            Nw = i + step;
   1256            while (Nx < 0) {         /* we need to know about next char */
   1257                if(Nw == iend) {
   1258                    nextLink = 0;
   1259                    Nx = 3000;
   1260                } else {
   1261                    nextLink = getLink(dest[Nw]);
   1262                    if((nextLink & IRRELEVANT) == 0) {
   1263                        Nx = Nw;
   1264                    } else {
   1265                        Nw = Nw + step;
   1266                    }
   1267                }
   1268            }
   1269 
   1270            if ( ((currLink & ALEFTYPE) > 0)  &&  ((lastLink & LAMTYPE) > 0) ) {
   1271                lamalef_found = 1;
   1272                wLamalef = changeLamAlef(dest[i]); /*get from 0x065C-0x065f */
   1273                if ( wLamalef != 0) {
   1274                    dest[i] = LAMALEF_SPACE_SUB;            /* The default case is to drop the Alef and replace */
   1275                    dest[lastPos] =wLamalef;     /* it by LAMALEF_SPACE_SUB which is the last character in the  */
   1276                    i=lastPos;                   /* unicode private use area, this is done to make   */
   1277                }                                /* sure that removeLamAlefSpaces() handles only the */
   1278                lastLink = prevLink;             /* spaces generated during lamalef generation.      */
   1279                currLink = getLink(wLamalef);    /* LAMALEF_SPACE_SUB is added here and is replaced by spaces   */
   1280            }                                    /* in removeLamAlefSpaces()                         */
   1281 
   1282            if ((i > 0) && (dest[i-1] == SPACE_CHAR)){
   1283                if ( isSeenFamilyChar(dest[i])) {
   1284                    seenfamFound = 1;
   1285                } else if (dest[i] == YEH_HAMZA_CHAR) {
   1286                    yehhamzaFound = 1;
   1287                }
   1288            }
   1289            else if(i==0){
   1290                if ( isSeenFamilyChar(dest[i])){
   1291                    seenfamFound = 1;
   1292                } else if (dest[i] == YEH_HAMZA_CHAR) {
   1293                    yehhamzaFound = 1;
   1294                }
   1295            }
   1296 
   1297            /*
   1298             * get the proper shape according to link ability of neighbors
   1299             * and of character; depends on the order of the shapes
   1300             * (isolated, initial, middle, final) in the compatibility area
   1301             */
   1302            Shape = shapeTable[nextLink & (LINKR + LINKL)]
   1303                              [lastLink & (LINKR + LINKL)]
   1304                              [currLink & (LINKR + LINKL)];
   1305 
   1306            if ((currLink & (LINKR+LINKL)) == 1) {
   1307                Shape &= 1;
   1308            } else if(isTashkeelChar(dest[i])) {
   1309                if( (lastLink & LINKL) && (nextLink & LINKR) && (tashkeelFlag == 1) &&
   1310                     dest[i] != 0x064C && dest[i] != 0x064D )
   1311                {
   1312                    Shape = 1;
   1313                    if( (nextLink&ALEFTYPE) == ALEFTYPE && (lastLink&LAMTYPE) == LAMTYPE ) {
   1314                        Shape = 0;
   1315                    }
   1316                } else if(tashkeelFlag == 2 && dest[i] == SHADDA06_CHAR){
   1317                    Shape = 1;
   1318                } else {
   1319                    Shape = 0;
   1320                }
   1321            }
   1322            if ((dest[i] ^ 0x0600) < 0x100) {
   1323                if ( isTashkeelChar(dest[i]) ){
   1324                    if (tashkeelFlag == 2  && dest[i] != SHADDA06_CHAR){
   1325                        dest[i] = TASHKEEL_SPACE_SUB;
   1326                        tashkeelFound  = 1;
   1327                    } else {
   1328                        /* to ensure the array index is within the range */
   1329                        U_ASSERT(dest[i] >= 0x064Bu
   1330                            && dest[i]-0x064Bu < UPRV_LENGTHOF(IrrelevantPos));
   1331                        dest[i] =  0xFE70 + IrrelevantPos[(dest[i] - 0x064B)] + static_cast<char16_t>(Shape);
   1332                    }
   1333                }else if ((currLink & APRESENT) > 0) {
   1334                    dest[i] = static_cast<char16_t>(0xFB50 + (currLink >> 8) + Shape);
   1335                }else if ((currLink >> 8) > 0 && (currLink & IRRELEVANT) == 0) {
   1336                    dest[i] = static_cast<char16_t>(0xFE70 + (currLink >> 8) + Shape);
   1337                }
   1338            }
   1339        }
   1340 
   1341        /* move one notch forward */
   1342        if ((currLink & IRRELEVANT) == 0) {
   1343            prevLink = lastLink;
   1344            lastLink = currLink;
   1345            lastPos = i;
   1346        }
   1347 
   1348        i = i + step;
   1349        if (i == Nx) {
   1350            currLink = nextLink;
   1351            Nx = -2;
   1352        } else if(i != iend) {
   1353            currLink = getLink(dest[i]);
   1354        }
   1355    }
   1356    destSize = sourceLength;
   1357    if ( (lamalef_found != 0 ) || (tashkeelFound  != 0) ){
   1358        destSize = handleGeneratedSpaces(dest,sourceLength,destSize,options,pErrorCode, shapeVars);
   1359    }
   1360 
   1361    if ( (seenfamFound != 0) || (yehhamzaFound != 0) ) {
   1362        destSize = expandCompositChar(dest, sourceLength,destSize,options,pErrorCode, SHAPE_MODE,shapeVars);
   1363    }
   1364    return destSize;
   1365 }
   1366 
   1367 /*
   1368 *Name     : deShapeUnicode
   1369 *Function : Converts an Arabic Unicode buffer in FExx Range into unshaped
   1370 *           arabic Unicode buffer in 06xx Range
   1371 */
   1372 static int32_t
   1373 deShapeUnicode(char16_t *dest, int32_t sourceLength,
   1374               int32_t destSize,uint32_t options,
   1375               UErrorCode *pErrorCode, struct uShapeVariables shapeVars) {
   1376    int32_t i = 0;
   1377    int32_t lamalef_found = 0;
   1378    int32_t yehHamzaComposeEnabled = 0;
   1379    int32_t seenComposeEnabled = 0;
   1380 
   1381    yehHamzaComposeEnabled = ((options&U_SHAPE_YEHHAMZA_MASK) == U_SHAPE_YEHHAMZA_TWOCELL_NEAR) ? 1 : 0;
   1382    seenComposeEnabled = ((options&U_SHAPE_SEEN_MASK) == U_SHAPE_SEEN_TWOCELL_NEAR)? 1 : 0;
   1383 
   1384    /*
   1385     *This for loop changes the buffer from the Unicode FE range to
   1386     *the Unicode 06 range
   1387     */
   1388 
   1389    for(i = 0; i < sourceLength; i++) {
   1390        char16_t  inputChar = dest[i];
   1391        if ( (inputChar >= 0xFB50) && (inputChar <= 0xFBFF)) { /* FBxx Arabic range */
   1392            char16_t c = convertFBto06 [ (inputChar - 0xFB50) ];
   1393            if (c != 0)
   1394                dest[i] = c;
   1395        } else if( (yehHamzaComposeEnabled == 1) && ((inputChar == HAMZA06_CHAR) || (inputChar == HAMZAFE_CHAR))
   1396                && (i < (sourceLength - 1)) && isAlefMaksouraChar(dest[i+1] )) {
   1397                 dest[i] = SPACE_CHAR;
   1398                 dest[i+1] = YEH_HAMZA_CHAR;
   1399        } else if ( (seenComposeEnabled == 1) && (isTailChar(inputChar)) && (i< (sourceLength - 1))
   1400                        && (isSeenTailFamilyChar(dest[i+1])) ) {
   1401                dest[i] = SPACE_CHAR;
   1402        } else if (( inputChar >= 0xFE70) && (inputChar <= 0xFEF4 )) { /* FExx Arabic range */
   1403                dest[i] = convertFEto06 [ (inputChar - 0xFE70) ];
   1404        } else {
   1405            dest[i] = inputChar ;
   1406        }
   1407 
   1408        if( isLamAlefChar(dest[i]) )
   1409            lamalef_found = 1;
   1410    }
   1411 
   1412   destSize = sourceLength;
   1413   if (lamalef_found != 0){
   1414          destSize = expandCompositChar(dest,sourceLength,destSize,options,pErrorCode,DESHAPE_MODE, shapeVars);
   1415   }
   1416   return destSize;
   1417 }
   1418 
   1419 /*
   1420 ****************************************
   1421 * u_shapeArabic
   1422 ****************************************
   1423 */
   1424 
   1425 U_CAPI int32_t U_EXPORT2
   1426 u_shapeArabic(const char16_t *source, int32_t sourceLength,
   1427              char16_t *dest, int32_t destCapacity,
   1428              uint32_t options,
   1429              UErrorCode *pErrorCode) {
   1430 
   1431    int32_t destLength;
   1432    struct  uShapeVariables shapeVars = { OLD_TAIL_CHAR,U_SHAPE_LAMALEF_BEGIN,U_SHAPE_LAMALEF_END,U_SHAPE_TASHKEEL_BEGIN,U_SHAPE_TASHKEEL_END,0};
   1433 
   1434    /* usual error checking */
   1435    if(pErrorCode==nullptr || U_FAILURE(*pErrorCode)) {
   1436        return 0;
   1437    }
   1438 
   1439    /* make sure that no reserved options values are used; allow dest==nullptr only for preflighting */
   1440    if( source==nullptr || sourceLength<-1 || (dest==nullptr && destCapacity!=0) || destCapacity<0 ||
   1441                (((options&U_SHAPE_TASHKEEL_MASK) > 0) &&
   1442                 ((options&U_SHAPE_LETTERS_SHAPE_TASHKEEL_ISOLATED) == U_SHAPE_LETTERS_SHAPE_TASHKEEL_ISOLATED) ) ||
   1443                (((options&U_SHAPE_TASHKEEL_MASK) > 0) &&
   1444                 ((options&U_SHAPE_LETTERS_MASK) == U_SHAPE_LETTERS_UNSHAPE)) ||
   1445                (options&U_SHAPE_DIGIT_TYPE_RESERVED)==U_SHAPE_DIGIT_TYPE_RESERVED ||
   1446                (options&U_SHAPE_DIGITS_MASK)==U_SHAPE_DIGITS_RESERVED ||
   1447                ((options&U_SHAPE_LAMALEF_MASK) != U_SHAPE_LAMALEF_RESIZE  &&
   1448                (options&U_SHAPE_AGGREGATE_TASHKEEL_MASK) != 0) ||
   1449                ((options&U_SHAPE_AGGREGATE_TASHKEEL_MASK) == U_SHAPE_AGGREGATE_TASHKEEL &&
   1450                (options&U_SHAPE_LETTERS_SHAPE_TASHKEEL_ISOLATED) != U_SHAPE_LETTERS_SHAPE_TASHKEEL_ISOLATED)
   1451    )
   1452    {
   1453        *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
   1454        return 0;
   1455    }
   1456    /* Validate  lamalef options */
   1457    if(((options&U_SHAPE_LAMALEF_MASK) > 0)&&
   1458              !(((options & U_SHAPE_LAMALEF_MASK)==U_SHAPE_LAMALEF_BEGIN) ||
   1459                ((options & U_SHAPE_LAMALEF_MASK)==U_SHAPE_LAMALEF_END ) ||
   1460                ((options & U_SHAPE_LAMALEF_MASK)==U_SHAPE_LAMALEF_RESIZE )||
   1461                 ((options & U_SHAPE_LAMALEF_MASK)==U_SHAPE_LAMALEF_AUTO) ||
   1462                 ((options & U_SHAPE_LAMALEF_MASK)==U_SHAPE_LAMALEF_NEAR)))
   1463    {
   1464         *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
   1465        return 0;
   1466    }
   1467    /* Validate  Tashkeel options */
   1468    if(((options&U_SHAPE_TASHKEEL_MASK) > 0)&&
   1469                   !(((options & U_SHAPE_TASHKEEL_MASK)==U_SHAPE_TASHKEEL_BEGIN) ||
   1470                     ((options & U_SHAPE_TASHKEEL_MASK)==U_SHAPE_TASHKEEL_END )
   1471                    ||((options & U_SHAPE_TASHKEEL_MASK)==U_SHAPE_TASHKEEL_RESIZE )||
   1472                    ((options & U_SHAPE_TASHKEEL_MASK)==U_SHAPE_TASHKEEL_REPLACE_BY_TATWEEL)))
   1473    {
   1474         *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
   1475        return 0;
   1476    }
   1477    /* determine the source length */
   1478    if(sourceLength==-1) {
   1479        sourceLength=u_strlen(source);
   1480    }
   1481    if(sourceLength<=0) {
   1482        return u_terminateUChars(dest, destCapacity, 0, pErrorCode);
   1483    }
   1484 
   1485    /* check that source and destination do not overlap */
   1486    if( dest!=nullptr &&
   1487        ((source<=dest && dest<source+sourceLength) ||
   1488         (dest<=source && source<dest+destCapacity))) {
   1489        *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
   1490        return 0;
   1491    }
   1492 
   1493    /* Does Options contain the new Seen Tail Unicode code point option */
   1494    if ( (options&U_SHAPE_TAIL_TYPE_MASK) == U_SHAPE_TAIL_NEW_UNICODE){
   1495        shapeVars.tailChar = NEW_TAIL_CHAR;
   1496    }else {
   1497        shapeVars.tailChar = OLD_TAIL_CHAR;
   1498    }
   1499 
   1500    if((options&U_SHAPE_LETTERS_MASK)!=U_SHAPE_LETTERS_NOOP) {
   1501        char16_t buffer[300];
   1502        char16_t *tempbuffer, *tempsource = nullptr;
   1503        int32_t outputSize, spacesCountl=0, spacesCountr=0;
   1504 
   1505        if((options&U_SHAPE_AGGREGATE_TASHKEEL_MASK)>0) {
   1506            int32_t logical_order = (options&U_SHAPE_TEXT_DIRECTION_MASK) == U_SHAPE_TEXT_DIRECTION_LOGICAL;
   1507            int32_t aggregate_tashkeel =
   1508                        (options&(U_SHAPE_AGGREGATE_TASHKEEL_MASK+U_SHAPE_LETTERS_SHAPE_TASHKEEL_ISOLATED)) ==
   1509                        (U_SHAPE_AGGREGATE_TASHKEEL+U_SHAPE_LETTERS_SHAPE_TASHKEEL_ISOLATED);
   1510            int step=logical_order?1:-1;
   1511            int j=logical_order?-1:2*sourceLength;
   1512            int i=logical_order?-1:sourceLength;
   1513            int end=logical_order?sourceLength:-1;
   1514            int aggregation_possible = 1;
   1515            char16_t prev = 0;
   1516            char16_t prevLink, currLink = 0;
   1517            int newSourceLength = 0;
   1518            tempsource = (char16_t *)uprv_malloc(2*sourceLength*U_SIZEOF_UCHAR);
   1519            if(tempsource == nullptr) {
   1520                *pErrorCode = U_MEMORY_ALLOCATION_ERROR;
   1521                return 0;
   1522            }
   1523 
   1524            while ((i+=step) != end) {
   1525                prevLink = currLink;
   1526                currLink = getLink(source[i]);
   1527                if (aggregate_tashkeel && ((prevLink|currLink)&COMBINE) == COMBINE && aggregation_possible) {
   1528                    aggregation_possible = 0;
   1529                    tempsource[j] = (prev<source[i]?prev:source[i])-0x064C+0xFC5E;
   1530                    currLink = getLink(tempsource[j]);
   1531                } else {
   1532                    aggregation_possible = 1;
   1533                    tempsource[j+=step] = source[i];
   1534                    prev = source[i];
   1535                    newSourceLength++;
   1536                }
   1537            }
   1538            source = tempsource+(logical_order?0:j);
   1539            sourceLength = newSourceLength;
   1540        }
   1541 
   1542        /* calculate destination size */
   1543        /* TODO: do we ever need to do this pure preflighting? */
   1544        if(((options&U_SHAPE_LAMALEF_MASK)==U_SHAPE_LAMALEF_RESIZE) ||
   1545           ((options&U_SHAPE_TASHKEEL_MASK)==U_SHAPE_TASHKEEL_RESIZE)) {
   1546            outputSize=calculateSize(source,sourceLength,destCapacity,options);
   1547        } else {
   1548            outputSize=sourceLength;
   1549        }
   1550 
   1551        if(outputSize>destCapacity) {
   1552            *pErrorCode=U_BUFFER_OVERFLOW_ERROR;
   1553                if (tempsource != nullptr) uprv_free(tempsource);
   1554            return outputSize;
   1555        }
   1556 
   1557        /*
   1558         * need a temporary buffer of size max(outputSize, sourceLength)
   1559         * because at first we copy source->temp
   1560         */
   1561        if(sourceLength>outputSize) {
   1562            outputSize=sourceLength;
   1563        }
   1564 
   1565        /* Start of Arabic letter shaping part */
   1566        if(outputSize<=UPRV_LENGTHOF(buffer)) {
   1567            outputSize=UPRV_LENGTHOF(buffer);
   1568            tempbuffer=buffer;
   1569        } else {
   1570            tempbuffer = (char16_t *)uprv_malloc(outputSize*U_SIZEOF_UCHAR);
   1571 
   1572            /*Test for nullptr*/
   1573            if(tempbuffer == nullptr) {
   1574                *pErrorCode = U_MEMORY_ALLOCATION_ERROR;
   1575                if (tempsource != nullptr) uprv_free(tempsource);
   1576                return 0;
   1577            }
   1578        }
   1579        u_memcpy(tempbuffer, source, sourceLength);
   1580        if (tempsource != nullptr){
   1581            uprv_free(tempsource);
   1582        }
   1583 
   1584        if(sourceLength<outputSize) {
   1585            uprv_memset(tempbuffer+sourceLength, 0, (outputSize-sourceLength)*U_SIZEOF_UCHAR);
   1586        }
   1587 
   1588        if((options&U_SHAPE_TEXT_DIRECTION_MASK) == U_SHAPE_TEXT_DIRECTION_LOGICAL) {
   1589            countSpaces(tempbuffer,sourceLength,options,&spacesCountl,&spacesCountr);
   1590            invertBuffer(tempbuffer,sourceLength,options,spacesCountl,spacesCountr);
   1591        }
   1592 
   1593        if((options&U_SHAPE_TEXT_DIRECTION_MASK) == U_SHAPE_TEXT_DIRECTION_VISUAL_LTR) {
   1594            if((options&U_SHAPE_SPACES_RELATIVE_TO_TEXT_MASK) == U_SHAPE_SPACES_RELATIVE_TO_TEXT_BEGIN_END) {
   1595                shapeVars.spacesRelativeToTextBeginEnd = 1;
   1596                shapeVars.uShapeLamalefBegin = U_SHAPE_LAMALEF_END;
   1597                shapeVars.uShapeLamalefEnd = U_SHAPE_LAMALEF_BEGIN;
   1598                shapeVars.uShapeTashkeelBegin = U_SHAPE_TASHKEEL_END;
   1599                shapeVars.uShapeTashkeelEnd = U_SHAPE_TASHKEEL_BEGIN;
   1600            }
   1601        }
   1602 
   1603        switch(options&U_SHAPE_LETTERS_MASK) {
   1604        case U_SHAPE_LETTERS_SHAPE :
   1605             if( (options&U_SHAPE_TASHKEEL_MASK)> 0
   1606                 && ((options&U_SHAPE_TASHKEEL_MASK) !=U_SHAPE_TASHKEEL_REPLACE_BY_TATWEEL)) {
   1607                /* Call the shaping function with tashkeel flag == 2 for removal of tashkeel */
   1608                destLength = shapeUnicode(tempbuffer,sourceLength,destCapacity,options,pErrorCode,2,shapeVars);
   1609             }else {
   1610                /* default Call the shaping function with tashkeel flag == 1 */
   1611                destLength = shapeUnicode(tempbuffer,sourceLength,destCapacity,options,pErrorCode,1,shapeVars);
   1612 
   1613                /*After shaping text check if user wants to remove tashkeel and replace it with tatweel*/
   1614                if( (options&U_SHAPE_TASHKEEL_MASK) == U_SHAPE_TASHKEEL_REPLACE_BY_TATWEEL){
   1615                  destLength = handleTashkeelWithTatweel(tempbuffer,destLength,destCapacity,options,pErrorCode);
   1616                }
   1617            }
   1618            break;
   1619        case U_SHAPE_LETTERS_SHAPE_TASHKEEL_ISOLATED :
   1620            /* Call the shaping function with tashkeel flag == 0 */
   1621            destLength = shapeUnicode(tempbuffer,sourceLength,destCapacity,options,pErrorCode,0,shapeVars);
   1622            break;
   1623 
   1624        case U_SHAPE_LETTERS_UNSHAPE :
   1625            /* Call the deshaping function */
   1626            destLength = deShapeUnicode(tempbuffer,sourceLength,destCapacity,options,pErrorCode,shapeVars);
   1627            break;
   1628        default :
   1629            /* will never occur because of validity checks above */
   1630            destLength = 0;
   1631            break;
   1632        }
   1633 
   1634        /*
   1635         * TODO: (markus 2002aug01)
   1636         * For as long as we always preflight the outputSize above
   1637         * we should U_ASSERT(outputSize==destLength)
   1638         * except for the adjustment above before the tempbuffer allocation
   1639         */
   1640 
   1641        if((options&U_SHAPE_TEXT_DIRECTION_MASK) == U_SHAPE_TEXT_DIRECTION_LOGICAL) {
   1642            countSpaces(tempbuffer,destLength,options,&spacesCountl,&spacesCountr);
   1643            invertBuffer(tempbuffer,destLength,options,spacesCountl,spacesCountr);
   1644        }
   1645        u_memcpy(dest, tempbuffer, uprv_min(destLength, destCapacity));
   1646 
   1647        if(tempbuffer!=buffer) {
   1648            uprv_free(tempbuffer);
   1649        }
   1650 
   1651        if(destLength>destCapacity) {
   1652            *pErrorCode=U_BUFFER_OVERFLOW_ERROR;
   1653            return destLength;
   1654        }
   1655 
   1656        /* End of Arabic letter shaping part */
   1657    } else {
   1658        /*
   1659         * No letter shaping:
   1660         * just make sure the destination is large enough and copy the string.
   1661         */
   1662        if(destCapacity<sourceLength) {
   1663            /* this catches preflighting, too */
   1664            *pErrorCode=U_BUFFER_OVERFLOW_ERROR;
   1665            return sourceLength;
   1666        }
   1667        u_memcpy(dest, source, sourceLength);
   1668        destLength=sourceLength;
   1669    }
   1670 
   1671    /*
   1672     * Perform number shaping.
   1673     * With UTF-16 or UTF-32, the length of the string is constant.
   1674     * The easiest way to do this is to operate on the destination and
   1675     * "shape" the digits in-place.
   1676     */
   1677    if((options&U_SHAPE_DIGITS_MASK)!=U_SHAPE_DIGITS_NOOP) {
   1678        char16_t digitBase;
   1679        int32_t i;
   1680 
   1681        /* select the requested digit group */
   1682        switch(options&U_SHAPE_DIGIT_TYPE_MASK) {
   1683        case U_SHAPE_DIGIT_TYPE_AN:
   1684            digitBase=0x660; /* Unicode: "Arabic-Indic digits" */
   1685            break;
   1686        case U_SHAPE_DIGIT_TYPE_AN_EXTENDED:
   1687            digitBase=0x6f0; /* Unicode: "Eastern Arabic-Indic digits (Persian and Urdu)" */
   1688            break;
   1689        default:
   1690            /* will never occur because of validity checks above */
   1691            digitBase=0;
   1692            break;
   1693        }
   1694 
   1695        /* perform the requested operation */
   1696        switch(options&U_SHAPE_DIGITS_MASK) {
   1697        case U_SHAPE_DIGITS_EN2AN:
   1698            /* add (digitBase-'0') to each European (ASCII) digit code point */
   1699            digitBase-=0x30;
   1700            for(i=0; i<destLength; ++i) {
   1701                if(((uint32_t)dest[i]-0x30)<10) {
   1702                    dest[i]+=digitBase;
   1703                }
   1704            }
   1705            break;
   1706        case U_SHAPE_DIGITS_AN2EN:
   1707            /* subtract (digitBase-'0') from each Arabic digit code point */
   1708            for(i=0; i<destLength; ++i) {
   1709                if(((uint32_t)dest[i]-(uint32_t)digitBase)<10) {
   1710                    dest[i]-=digitBase-0x30;
   1711                }
   1712            }
   1713            break;
   1714        case U_SHAPE_DIGITS_ALEN2AN_INIT_LR:
   1715            _shapeToArabicDigitsWithContext(dest, destLength,
   1716                                            digitBase,
   1717                                            (options & U_SHAPE_TEXT_DIRECTION_MASK) == U_SHAPE_TEXT_DIRECTION_LOGICAL,
   1718                                            false);
   1719            break;
   1720        case U_SHAPE_DIGITS_ALEN2AN_INIT_AL:
   1721            _shapeToArabicDigitsWithContext(dest, destLength,
   1722                                            digitBase,
   1723                                            (options & U_SHAPE_TEXT_DIRECTION_MASK) == U_SHAPE_TEXT_DIRECTION_LOGICAL,
   1724                                            true);
   1725            break;
   1726        default:
   1727            /* will never occur because of validity checks above */
   1728            break;
   1729        }
   1730    }
   1731 
   1732    return u_terminateUChars(dest, destCapacity, destLength, pErrorCode);
   1733 }