icuSources/common/unicode/ushape.h

   1 /*
   2 ******************************************************************************
   3 *
   4 *   Copyright (C) 2000-2012, International Business Machines
   5 *   Corporation and others.  All Rights Reserved.
   6 *
   7 ******************************************************************************
   8 *   file name:  ushape.h
   9 *   encoding:   US-ASCII
  10 *   tab size:   8 (not used)
  11 *   indentation:4
  12 *
  13 *   created on: 2000jun29
  14 *   created by: Markus W. Scherer
  15 */
  16
  17 #ifndef __USHAPE_H__
  18 #define __USHAPE_H__
  19
  20 #include "unicode/utypes.h"
  21
  22 /**
  23  * \file
  24  * \brief C API:  Arabic shaping
  25  *
  26  */
  27
  28 /**
  29  * Shape Arabic text on a character basis.
  30  *
  31  * <p>This function performs basic operations for "shaping" Arabic text. It is most
  32  * useful for use with legacy data formats and legacy display technology
  33  * (simple terminals). All operations are performed on Unicode characters.</p>
  34  *
  35  * <p>Text-based shaping means that some character code points in the text are
  36  * replaced by others depending on the context. It transforms one kind of text
  37  * into another. In comparison, modern displays for Arabic text select
  38  * appropriate, context-dependent font glyphs for each text element, which means
  39  * that they transform text into a glyph vector.</p>
  40  *
  41  * <p>Text transformations are necessary when modern display technology is not
  42  * available or when text needs to be transformed to or from legacy formats that
  43  * use "shaped" characters. Since the Arabic script is cursive, connecting
  44  * adjacent letters to each other, computers select images for each letter based
  45  * on the surrounding letters. This usually results in four images per Arabic
  46  * letter: initial, middle, final, and isolated forms. In Unicode, on the other
  47  * hand, letters are normally stored abstract, and a display system is expected
  48  * to select the necessary glyphs. (This makes searching and other text
  49  * processing easier because the same letter has only one code.) It is possible
  50  * to mimic this with text transformations because there are characters in
  51  * Unicode that are rendered as letters with a specific shape
  52  * (or cursive connectivity). They were included for interoperability with
  53  * legacy systems and codepages, and for unsophisticated display systems.</p>
  54  *
  55  * <p>A second kind of text transformations is supported for Arabic digits:
  56  * For compatibility with legacy codepages that only include European digits,
  57  * it is possible to replace one set of digits by another, changing the
  58  * character code points. These operations can be performed for either
  59  * Arabic-Indic Digits (U+0660...U+0669) or Eastern (Extended) Arabic-Indic
  60  * digits (U+06f0...U+06f9).</p>
  61  *
  62  * <p>Some replacements may result in more or fewer characters (code points).
  63  * By default, this means that the destination buffer may receive text with a
  64  * length different from the source length. Some legacy systems rely on the
  65  * length of the text to be constant. They expect extra spaces to be added
  66  * or consumed either next to the affected character or at the end of the
  67  * text.</p>
  68  *
  69  * <p>For details about the available operations, see the description of the
  70  * <code>U_SHAPE_...</code> options.</p>
  71  *
  72  * @param source The input text.
  73  *
  74  * @param sourceLength The number of UChars in <code>source</code>.
  75  *
  76  * @param dest The destination buffer that will receive the results of the
  77  *             requested operations. It may be <code>NULL</code> only if
  78  *             <code>destSize</code> is 0. The source and destination must not
  79  *             overlap.
  80  *
  81  * @param destSize The size (capacity) of the destination buffer in UChars.
  82  *                 If <code>destSize</code> is 0, then no output is produced,
  83  *                 but the necessary buffer size is returned ("preflighting").
  84  *
  85  * @param options This is a 32-bit set of flags that specify the operations
  86  *                that are performed on the input text. If no error occurs,
  87  *                then the result will always be written to the destination
  88  *                buffer.
  89  *
  90  * @param pErrorCode must be a valid pointer to an error code value,
  91  *        which must not indicate a failure before the function call.
  92  *
  93  * @return The number of UChars written to the destination buffer.
  94  *         If an error occured, then no output was written, or it may be
  95  *         incomplete. If <code>U_BUFFER_OVERFLOW_ERROR</code> is set, then
  96  *         the return value indicates the necessary destination buffer size.
  97  * @stable ICU 2.0
  98  */
  99 U_STABLE int32_t U_EXPORT2
 100 u_shapeArabic(const UChar *source, int32_t sourceLength,
 101               UChar *dest, int32_t destSize,
 102               uint32_t options,
 103               UErrorCode *pErrorCode);
 104
 105 /**
 106  * Memory option: allow the result to have a different length than the source.
 107  * Affects: LamAlef options
 108  * @stable ICU 2.0
 109  */
 110 #define U_SHAPE_LENGTH_GROW_SHRINK              0
 111
 112 /**
 113  * Memory option: allow the result to have a different length than the source.
 114  * Affects: LamAlef options
 115  * This option is an alias to U_SHAPE_LENGTH_GROW_SHRINK
 116  * @stable ICU 4.2
 117  */
 118 #define U_SHAPE_LAMALEF_RESIZE                  0
 119
 120 /**
 121  * Memory option: the result must have the same length as the source.
 122  * If more room is necessary, then try to consume spaces next to modified characters.
 123  * @stable ICU 2.0
 124  */
 125 #define U_SHAPE_LENGTH_FIXED_SPACES_NEAR        1
 126
 127 /**
 128  * Memory option: the result must have the same length as the source.
 129  * If more room is necessary, then try to consume spaces next to modified characters.
 130  * Affects: LamAlef options
 131  * This option is an alias to U_SHAPE_LENGTH_FIXED_SPACES_NEAR
 132  * @stable ICU 4.2
 133  */
 134 #define U_SHAPE_LAMALEF_NEAR                    1
 135
 136 /**
 137  * Memory option: the result must have the same length as the source.
 138  * If more room is necessary, then try to consume spaces at the end of the text.
 139  * @stable ICU 2.0
 140  */
 141 #define U_SHAPE_LENGTH_FIXED_SPACES_AT_END      2
 142
 143 /**
 144  * Memory option: the result must have the same length as the source.
 145  * If more room is necessary, then try to consume spaces at the end of the text.
 146  * Affects: LamAlef options
 147  * This option is an alias to U_SHAPE_LENGTH_FIXED_SPACES_AT_END
 148  * @stable ICU 4.2
 149  */
 150 #define U_SHAPE_LAMALEF_END                     2
 151
 152 /**
 153  * Memory option: the result must have the same length as the source.
 154  * If more room is necessary, then try to consume spaces at the beginning of the text.
 155  * @stable ICU 2.0
 156  */
 157 #define U_SHAPE_LENGTH_FIXED_SPACES_AT_BEGINNING 3
 158
 159 /**
 160  * Memory option: the result must have the same length as the source.
 161  * If more room is necessary, then try to consume spaces at the beginning of the text.
 162  * Affects: LamAlef options
 163  * This option is an alias to U_SHAPE_LENGTH_FIXED_SPACES_AT_BEGINNING
 164  * @stable ICU 4.2
 165  */
 166 #define U_SHAPE_LAMALEF_BEGIN                    3
 167
 168
 169 /**
 170  * Memory option: the result must have the same length as the source.
 171  * Shaping Mode: For each LAMALEF character found, expand LAMALEF using space at end.
 172  *               If there is no space at end, use spaces at beginning of the buffer. If there
 173  *               is no space at beginning of the buffer, use spaces at the near (i.e. the space
 174  *               after the LAMALEF character).
 175  *               If there are no spaces found, an error U_NO_SPACE_AVAILABLE (as defined in utypes.h)
 176  *               will be set in pErrorCode
 177  *
 178  * Deshaping Mode: Perform the same function as the flag equals U_SHAPE_LAMALEF_END.
 179  * Affects: LamAlef options
 180  * @stable ICU 4.2
 181  */
 182 #define U_SHAPE_LAMALEF_AUTO                     0x10000
 183
 184 /** Bit mask for memory options. @stable ICU 2.0 */
 185 #define U_SHAPE_LENGTH_MASK                      0x10003 /* Changed old value 3 */
 186
 187
 188 /**
 189  * Bit mask for LamAlef memory options.
 190  * @stable ICU 4.2
 191  */
 192 #define U_SHAPE_LAMALEF_MASK                     0x10003 /* updated */
 193
 194 /** Direction indicator: the source is in logical (keyboard) order. @stable ICU 2.0 */
 195 #define U_SHAPE_TEXT_DIRECTION_LOGICAL          0
 196
 197 /**
 198  * Direction indicator:
 199  * the source is in visual RTL order,
 200  * the rightmost displayed character stored first.
 201  * This option is an alias to U_SHAPE_TEXT_DIRECTION_LOGICAL
 202  * @stable ICU 4.2
 203  */
 204 #define U_SHAPE_TEXT_DIRECTION_VISUAL_RTL       0
 205
 206 /**
 207  * Direction indicator:
 208  * the source is in visual LTR order,
 209  * the leftmost displayed character stored first.
 210  * @stable ICU 2.0
 211  */
 212 #define U_SHAPE_TEXT_DIRECTION_VISUAL_LTR       4
 213
 214 /** Bit mask for direction indicators. @stable ICU 2.0 */
 215 #define U_SHAPE_TEXT_DIRECTION_MASK             4
 216
 217
 218 /** Letter shaping option: do not perform letter shaping. @stable ICU 2.0 */
 219 #define U_SHAPE_LETTERS_NOOP                    0
 220
 221 /** Letter shaping option: replace abstract letter characters by "shaped" ones. @stable ICU 2.0 */
 222 #define U_SHAPE_LETTERS_SHAPE                   8
 223
 224 /** Letter shaping option: replace "shaped" letter characters by abstract ones. @stable ICU 2.0 */
 225 #define U_SHAPE_LETTERS_UNSHAPE                 0x10
 226
 227 /**
 228  * Letter shaping option: replace abstract letter characters by "shaped" ones.
 229  * The only difference with U_SHAPE_LETTERS_SHAPE is that Tashkeel letters
 230  * are always "shaped" into the isolated form instead of the medial form
 231  * (selecting code points from the Arabic Presentation Forms-B block).
 232  * @stable ICU 2.0
 233  */
 234 #define U_SHAPE_LETTERS_SHAPE_TASHKEEL_ISOLATED 0x18
 235
 236
 237 /** Bit mask for letter shaping options. @stable ICU 2.0 */
 238 #define U_SHAPE_LETTERS_MASK                        0x18
 239
 240
 241 /** Digit shaping option: do not perform digit shaping. @stable ICU 2.0 */
 242 #define U_SHAPE_DIGITS_NOOP                     0
 243
 244 /**
 245  * Digit shaping option:
 246  * Replace European digits (U+0030...) by Arabic-Indic digits.
 247  * @stable ICU 2.0
 248  */
 249 #define U_SHAPE_DIGITS_EN2AN                    0x20
 250
 251 /**
 252  * Digit shaping option:
 253  * Replace Arabic-Indic digits by European digits (U+0030...).
 254  * @stable ICU 2.0
 255  */
 256 #define U_SHAPE_DIGITS_AN2EN                    0x40
 257
 258 /**
 259  * Digit shaping option:
 260  * Replace European digits (U+0030...) by Arabic-Indic digits if the most recent
 261  * strongly directional character is an Arabic letter
 262  * (<code>u_charDirection()</code> result <code>U_RIGHT_TO_LEFT_ARABIC</code> [AL]).<br>
 263  * The direction of "preceding" depends on the direction indicator option.
 264  * For the first characters, the preceding strongly directional character
 265  * (initial state) is assumed to be not an Arabic letter
 266  * (it is <code>U_LEFT_TO_RIGHT</code> [L] or <code>U_RIGHT_TO_LEFT</code> [R]).
 267  * @stable ICU 2.0
 268  */
 269 #define U_SHAPE_DIGITS_ALEN2AN_INIT_LR          0x60
 270
 271 /**
 272  * Digit shaping option:
 273  * Replace European digits (U+0030...) by Arabic-Indic digits if the most recent
 274  * strongly directional character is an Arabic letter
 275  * (<code>u_charDirection()</code> result <code>U_RIGHT_TO_LEFT_ARABIC</code> [AL]).<br>
 276  * The direction of "preceding" depends on the direction indicator option.
 277  * For the first characters, the preceding strongly directional character
 278  * (initial state) is assumed to be an Arabic letter.
 279  * @stable ICU 2.0
 280  */
 281 #define U_SHAPE_DIGITS_ALEN2AN_INIT_AL          0x80
 282
 283 /** Not a valid option value. May be replaced by a new option. @stable ICU 2.0 */
 284 #define U_SHAPE_DIGITS_RESERVED                 0xa0
 285
 286 /** Bit mask for digit shaping options. @stable ICU 2.0 */
 287 #define U_SHAPE_DIGITS_MASK                     0xe0
 288
 289
 290 /** Digit type option: Use Arabic-Indic digits (U+0660...U+0669). @stable ICU 2.0 */
 291 #define U_SHAPE_DIGIT_TYPE_AN                   0
 292
 293 /** Digit type option: Use Eastern (Extended) Arabic-Indic digits (U+06f0...U+06f9). @stable ICU 2.0 */
 294 #define U_SHAPE_DIGIT_TYPE_AN_EXTENDED          0x100
 295
 296 /** Not a valid option value. May be replaced by a new option. @stable ICU 2.0 */
 297 #define U_SHAPE_DIGIT_TYPE_RESERVED             0x200
 298
 299 /** Bit mask for digit type options. @stable ICU 2.0 */
 300 #define U_SHAPE_DIGIT_TYPE_MASK                 0x300 /* I need to change this from 0x3f00 to 0x300 */
 301
 302 /**
 303  * Tashkeel aggregation option:
 304  * Replaces any combination of U+0651 with one of
 305  * U+064C, U+064D, U+064E, U+064F, U+0650 with
 306  * U+FC5E, U+FC5F, U+FC60, U+FC61, U+FC62 consecutively.
 307  * @stable ICU 3.6
 308  */
 309 #define U_SHAPE_AGGREGATE_TASHKEEL              0x4000
 310 /** Tashkeel aggregation option: do not aggregate tashkeels. @stable ICU 3.6 */
 311 #define U_SHAPE_AGGREGATE_TASHKEEL_NOOP         0
 312 /** Bit mask for tashkeel aggregation. @stable ICU 3.6 */
 313 #define U_SHAPE_AGGREGATE_TASHKEEL_MASK         0x4000
 314
 315 /**
 316  * Presentation form option:
 317  * Don't replace Arabic Presentation Forms-A and Arabic Presentation Forms-B
 318  * characters with 0+06xx characters, before shaping.
 319  * @stable ICU 3.6
 320  */
 321 #define U_SHAPE_PRESERVE_PRESENTATION           0x8000
 322 /** Presentation form option:
 323  * Replace Arabic Presentation Forms-A and Arabic Presentationo Forms-B with
 324  * their unshaped correspondants in range 0+06xx, before shaping.
 325  * @stable ICU 3.6
 326  */
 327 #define U_SHAPE_PRESERVE_PRESENTATION_NOOP      0
 328 /** Bit mask for preserve presentation form. @stable ICU 3.6 */
 329 #define U_SHAPE_PRESERVE_PRESENTATION_MASK      0x8000
 330
 331 /* Seen Tail option */
 332 /**
 333  * Memory option: the result must have the same length as the source.
 334  * Shaping mode: The SEEN family character will expand into two characters using space near
 335  *               the SEEN family character(i.e. the space after the character).
 336  *               If there are no spaces found, an error U_NO_SPACE_AVAILABLE (as defined in utypes.h)
 337  *               will be set in pErrorCode
 338  *
 339  * De-shaping mode: Any Seen character followed by Tail character will be
 340  *                  replaced by one cell Seen and a space will replace the Tail.
 341  * Affects: Seen options
 342  * @stable ICU 4.2
 343  */
 344 #define U_SHAPE_SEEN_TWOCELL_NEAR     0x200000
 345
 346 /**
 347  * Bit mask for Seen memory options.
 348  * @stable ICU 4.2
 349  */
 350 #define U_SHAPE_SEEN_MASK             0x700000
 351
 352 /* YehHamza option */
 353 /**
 354  * Memory option: the result must have the same length as the source.
 355  * Shaping mode: The YEHHAMZA character will expand into two characters using space near it
 356  *              (i.e. the space after the character
 357  *               If there are no spaces found, an error U_NO_SPACE_AVAILABLE (as defined in utypes.h)
 358  *               will be set in pErrorCode
 359  *
 360  * De-shaping mode: Any Yeh (final or isolated) character followed by Hamza character will be
 361  *                  replaced by one cell YehHamza and space will replace the Hamza.
 362  * Affects: YehHamza options
 363  * @stable ICU 4.2
 364  */
 365 #define U_SHAPE_YEHHAMZA_TWOCELL_NEAR      0x1000000
 366
 367
 368 /**
 369  * Bit mask for YehHamza memory options.
 370  * @stable ICU 4.2
 371  */
 372 #define U_SHAPE_YEHHAMZA_MASK              0x3800000
 373
 374 /* New Tashkeel options */
 375 /**
 376  * Memory option: the result must have the same length as the source.
 377  * Shaping mode: Tashkeel characters will be replaced by spaces.
 378  *               Spaces will be placed at beginning of the buffer
 379  *
 380  * De-shaping mode: N/A
 381  * Affects: Tashkeel options
 382  * @stable ICU 4.2
 383  */
 384 #define U_SHAPE_TASHKEEL_BEGIN                      0x40000
 385
 386 /**
 387  * Memory option: the result must have the same length as the source.
 388  * Shaping mode: Tashkeel characters will be replaced by spaces.
 389  *               Spaces will be placed at end of the buffer
 390  *
 391  * De-shaping mode: N/A
 392  * Affects: Tashkeel options
 393  * @stable ICU 4.2
 394  */
 395 #define U_SHAPE_TASHKEEL_END                        0x60000
 396
 397 /**
 398  * Memory option: allow the result to have a different length than the source.
 399  * Shaping mode: Tashkeel characters will be removed, buffer length will shrink.
 400  * De-shaping mode: N/A
 401  *
 402  * Affect: Tashkeel options
 403  * @stable ICU 4.2
 404  */
 405 #define U_SHAPE_TASHKEEL_RESIZE                     0x80000
 406
 407 /**
 408  * Memory option: the result must have the same length as the source.
 409  * Shaping mode: Tashkeel characters will be replaced by Tatweel if it is connected to adjacent
 410  *               characters (i.e. shaped on Tatweel) or replaced by space if it is not connected.
 411  *
 412  * De-shaping mode: N/A
 413  * Affects: YehHamza options
 414  * @stable ICU 4.2
 415  */
 416 #define U_SHAPE_TASHKEEL_REPLACE_BY_TATWEEL         0xC0000
 417
 418 /**
 419  * Bit mask for Tashkeel replacement with Space or Tatweel memory options.
 420  * @stable ICU 4.2
 421  */
 422 #define U_SHAPE_TASHKEEL_MASK                       0xE0000
 423
 424
 425 /* Space location Control options */
 426 /**
 427  * This option affect the meaning of BEGIN and END options. if this option is not used the default
 428  * for BEGIN and END will be as following:
 429  * The Default (for both Visual LTR, Visual RTL and Logical Text)
 430  *           1. BEGIN always refers to the start address of physical memory.
 431  *           2. END always refers to the end address of physical memory.
 432  *
 433  * If this option is used it will swap the meaning of BEGIN and END only for Visual LTR text.
 434  *
 435  * The effect on BEGIN and END Memory Options will be as following:
 436  *    A. BEGIN For Visual LTR text: This will be the beginning (right side) of the visual text(
 437  *       corresponding to the physical memory address end for Visual LTR text, Same as END in
 438  *       default behavior)
 439  *    B. BEGIN For Logical text: Same as BEGIN in default behavior.
 440  *    C. END For Visual LTR text: This will be the end (left side) of the visual text (corresponding
 441  *       to the physical memory address beginning for Visual LTR text, Same as BEGIN in default behavior.
 442  *    D. END For Logical text: Same as END in default behavior).
 443  * Affects: All LamAlef BEGIN, END and AUTO options.
 444  * @stable ICU 4.2
 445  */
 446 #define U_SHAPE_SPACES_RELATIVE_TO_TEXT_BEGIN_END 0x4000000
 447
 448 /**
 449  * Bit mask for swapping BEGIN and END for Visual LTR text
 450  * @stable ICU 4.2
 451  */
 452 #define U_SHAPE_SPACES_RELATIVE_TO_TEXT_MASK      0x4000000
 453
 454 /**
 455  * If this option is used, shaping will use the new Unicode code point for TAIL (i.e. 0xFE73).
 456  * If this option is not specified (Default), old unofficial Unicode TAIL code point is used (i.e. 0x200B)
 457  * De-shaping will not use this option as it will always search for both the new Unicode code point for the
 458  * TAIL (i.e. 0xFE73) or the old unofficial Unicode TAIL code point (i.e. 0x200B) and de-shape the
 459  * Seen-Family letter accordingly.
 460  *
 461  * Shaping Mode: Only shaping.
 462  * De-shaping Mode: N/A.
 463  * Affects: All Seen options
 464  * @stable ICU 4.8
 465  */
 466 #define U_SHAPE_TAIL_NEW_UNICODE        0x8000000
 467
 468 /**
 469  * Bit mask for new Unicode Tail option
 470  * @stable ICU 4.8
 471  */
 472 #define U_SHAPE_TAIL_TYPE_MASK          0x8000000
 473
 474 #endif