icuSources/common/utrie.h

   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) 2001-2011, International Business Machines
   7 *   Corporation and others.  All Rights Reserved.
   8 *
   9 ******************************************************************************
  10 *   file name:  utrie.h
  11 *   encoding:   UTF-8
  12 *   tab size:   8 (not used)
  13 *   indentation:4
  14 *
  15 *   created on: 2001nov08
  16 *   created by: Markus W. Scherer
  17 */
  18
  19 #ifndef __UTRIE_H__
  20 #define __UTRIE_H__
  21
  22 #include "unicode/utypes.h"
  23 #include "unicode/utf16.h"
  24
  25 U_CDECL_BEGIN
  26
  27 /**
  28  * \file
  29  *
  30  * This is a common implementation of a "folded" trie.
  31  * It is a kind of compressed, serializable table of 16- or 32-bit values associated with
  32  * Unicode code points (0..0x10ffff).
  33  *
  34  * This implementation is optimized for getting values while walking forward
  35  * through a UTF-16 string.
  36  * Therefore, the simplest and fastest access macros are the
  37  * _FROM_LEAD() and _FROM_OFFSET_TRAIL() macros.
  38  *
  39  * The _FROM_BMP() macros are a little more complicated; they get values
  40  * even for lead surrogate code _points_, while the _FROM_LEAD() macros
  41  * get special "folded" values for lead surrogate code _units_ if
  42  * there is relevant data associated with them.
  43  * From such a folded value, an offset needs to be extracted to supply
  44  * to the _FROM_OFFSET_TRAIL() macros.
  45  *
  46  * Most of the more complex (and more convenient) functions/macros call a callback function
  47  * to get that offset from the folded value for a lead surrogate unit.
  48  */
  49
  50 /**
  51  * Trie constants, defining shift widths, index array lengths, etc.
  52  */
  53 enum {
  54     /** Shift size for shifting right the input index. 1..9 */
  55     UTRIE_SHIFT=5,
  56
  57     /** Number of data values in a stage 2 (data array) block. 2, 4, 8, .., 0x200 */
  58     UTRIE_DATA_BLOCK_LENGTH=1<<UTRIE_SHIFT,
  59
  60     /** Mask for getting the lower bits from the input index. */
  61     UTRIE_MASK=UTRIE_DATA_BLOCK_LENGTH-1,
  62
  63     /**
  64      * Lead surrogate code points' index displacement in the index array.
  65      * 0x10000-0xd800=0x2800
  66      */
  67     UTRIE_LEAD_INDEX_DISP=0x2800>>UTRIE_SHIFT,
  68
  69     /**
  70      * Shift size for shifting left the index array values.
  71      * Increases possible data size with 16-bit index values at the cost
  72      * of compactability.
  73      * This requires blocks of stage 2 data to be aligned by UTRIE_DATA_GRANULARITY.
  74      * 0..UTRIE_SHIFT
  75      */
  76     UTRIE_INDEX_SHIFT=2,
  77
  78     /** The alignment size of a stage 2 data block. Also the granularity for compaction. */
  79     UTRIE_DATA_GRANULARITY=1<<UTRIE_INDEX_SHIFT,
  80
  81     /** Number of bits of a trail surrogate that are used in index table lookups. */
  82     UTRIE_SURROGATE_BLOCK_BITS=10-UTRIE_SHIFT,
  83
  84     /**
  85      * Number of index (stage 1) entries per lead surrogate.
  86      * Same as number of index entries for 1024 trail surrogates,
  87      * ==0x400>>UTRIE_SHIFT
  88      */
  89     UTRIE_SURROGATE_BLOCK_COUNT=(1<<UTRIE_SURROGATE_BLOCK_BITS),
  90
  91     /** Length of the BMP portion of the index (stage 1) array. */
  92     UTRIE_BMP_INDEX_LENGTH=0x10000>>UTRIE_SHIFT
  93 };
  94
  95 /**
  96  * Length of the index (stage 1) array before folding.
  97  * Maximum number of Unicode code points (0x110000) shifted right by UTRIE_SHIFT.
  98  */
  99 #define UTRIE_MAX_INDEX_LENGTH (0x110000>>UTRIE_SHIFT)
 100
 101 /**
 102  * Maximum length of the runtime data (stage 2) array.
 103  * Limited by 16-bit index values that are left-shifted by UTRIE_INDEX_SHIFT.
 104  */
 105 #define UTRIE_MAX_DATA_LENGTH (0x10000<<UTRIE_INDEX_SHIFT)
 106
 107 /**
 108  * Maximum length of the build-time data (stage 2) array.
 109  * The maximum length is 0x110000+UTRIE_DATA_BLOCK_LENGTH+0x400.
 110  * (Number of Unicode code points + one all-initial-value block +
 111  *  possible duplicate entries for 1024 lead surrogates.)
 112  */
 113 #define UTRIE_MAX_BUILD_TIME_DATA_LENGTH (0x110000+UTRIE_DATA_BLOCK_LENGTH+0x400)
 114
 115 /**
 116  * Number of bytes for a dummy trie.
 117  * A dummy trie is an empty runtime trie, used when a real data trie cannot
 118  * be loaded.
 119  * The number of bytes works for Latin-1-linear tries with 32-bit data
 120  * (worst case).
 121  *
 122  * Calculation:
 123  *   BMP index + 1 index block for lead surrogate code points +
 124  *   Latin-1-linear array + 1 data block for lead surrogate code points
 125  *
 126  * Latin-1: if(UTRIE_SHIFT<=8) { 256 } else { included in first data block }
 127  *
 128  * @see utrie_unserializeDummy
 129  */
 130 #define UTRIE_DUMMY_SIZE ((UTRIE_BMP_INDEX_LENGTH+UTRIE_SURROGATE_BLOCK_COUNT)*2+(UTRIE_SHIFT<=8?256:UTRIE_DATA_BLOCK_LENGTH)*4+UTRIE_DATA_BLOCK_LENGTH*4)
 131
 132 /**
 133  * Runtime UTrie callback function.
 134  * Extract from a lead surrogate's data the
 135  * index array offset of the indexes for that lead surrogate.
 136  *
 137  * @param data data value for a surrogate from the trie, including the folding offset
 138  * @return offset>=UTRIE_BMP_INDEX_LENGTH, or 0 if there is no data for the lead surrogate
 139  */
 140 typedef int32_t U_CALLCONV
 141 UTrieGetFoldingOffset(uint32_t data);
 142
 143 /**
 144  * Run-time Trie structure.
 145  *
 146  * Either the data table is 16 bits wide and accessed via the index
 147  * pointer, with each index item increased by indexLength;
 148  * in this case, data32==NULL.
 149  *
 150  * Or the data table is 32 bits wide and accessed via the data32 pointer.
 151  */
 152 struct UTrie {
 153     const uint16_t *index;
 154     const uint32_t *data32; /* NULL if 16b data is used via index */
 155
 156     /**
 157      * This function is not used in _FROM_LEAD, _FROM_BMP, and _FROM_OFFSET_TRAIL macros.
 158      * If convenience macros like _GET16 or _NEXT32 are used, this function must be set.
 159      *
 160      * utrie_unserialize() sets a default function which simply returns
 161      * the lead surrogate's value itself - which is the inverse of the default
 162      * folding function used by utrie_serialize().
 163      *
 164      * @see UTrieGetFoldingOffset
 165      */
 166     UTrieGetFoldingOffset *getFoldingOffset;
 167
 168     int32_t indexLength, dataLength;
 169     uint32_t initialValue;
 170     UBool isLatin1Linear;
 171 };
 172
 173 #ifndef __UTRIE2_H__
 174 typedef struct UTrie UTrie;
 175 #endif
 176
 177 /** Internal trie getter from an offset (0 if c16 is a BMP/lead units) and a 16-bit unit */
 178 #define _UTRIE_GET_RAW(trie, data, offset, c16) \
 179     (trie)->data[ \
 180         ((int32_t)((trie)->index[(offset)+((c16)>>UTRIE_SHIFT)])<<UTRIE_INDEX_SHIFT)+ \
 181         ((c16)&UTRIE_MASK) \
 182     ]
 183
 184 /** Internal trie getter from a pair of surrogates */
 185 #define _UTRIE_GET_FROM_PAIR(trie, data, c, c2, result, resultType) { \
 186     int32_t __offset; \
 187 \
 188     /* get data for lead surrogate */ \
 189     (result)=_UTRIE_GET_RAW((trie), data, 0, (c)); \
 190     __offset=(trie)->getFoldingOffset(result); \
 191 \
 192     /* get the real data from the folded lead/trail units */ \
 193     if(__offset>0) { \
 194         (result)=_UTRIE_GET_RAW((trie), data, __offset, (c2)&0x3ff); \
 195     } else { \
 196         (result)=(resultType)((trie)->initialValue); \
 197     } \
 198 }
 199
 200 /** Internal trie getter from a BMP code point, treating a lead surrogate as a normal code point */
 201 #define _UTRIE_GET_FROM_BMP(trie, data, c16) \
 202     _UTRIE_GET_RAW(trie, data, 0xd800<=(c16) && (c16)<=0xdbff ? UTRIE_LEAD_INDEX_DISP : 0, c16);
 203
 204 /**
 205  * Internal trie getter from a code point.
 206  * Could be faster(?) but longer with
 207  *   if((c32)<=0xd7ff) { (result)=_UTRIE_GET_RAW(trie, data, 0, c32); }
 208  */
 209 #define _UTRIE_GET(trie, data, c32, result, resultType) \
 210     if((uint32_t)(c32)<=0xffff) { \
 211         /* BMP code points */ \
 212         (result)=_UTRIE_GET_FROM_BMP(trie, data, c32); \
 213     } else if((uint32_t)(c32)<=0x10ffff) { \
 214         /* supplementary code point */ \
 215         UChar __lead16=U16_LEAD(c32); \
 216         _UTRIE_GET_FROM_PAIR(trie, data, __lead16, c32, result, resultType); \
 217     } else { \
 218         /* out of range */ \
 219         (result)=(resultType)((trie)->initialValue); \
 220     }
 221
 222 /** Internal next-post-increment: get the next code point (c, c2) and its data */
 223 #define _UTRIE_NEXT(trie, data, src, limit, c, c2, result, resultType) { \
 224     (c)=*(src)++; \
 225     if(!U16_IS_LEAD(c)) { \
 226         (c2)=0; \
 227         (result)=_UTRIE_GET_RAW((trie), data, 0, (c)); \
 228     } else if((src)!=(limit) && U16_IS_TRAIL((c2)=*(src))) { \
 229         ++(src); \
 230         _UTRIE_GET_FROM_PAIR((trie), data, (c), (c2), (result), resultType); \
 231     } else { \
 232         /* unpaired lead surrogate code point */ \
 233         (c2)=0; \
 234         (result)=_UTRIE_GET_RAW((trie), data, UTRIE_LEAD_INDEX_DISP, (c)); \
 235     } \
 236 }
 237
 238 /** Internal previous: get the previous code point (c, c2) and its data */
 239 #define _UTRIE_PREVIOUS(trie, data, start, src, c, c2, result, resultType) { \
 240     (c)=*--(src); \
 241     if(!U16_IS_SURROGATE(c)) { \
 242         (c2)=0; \
 243         (result)=_UTRIE_GET_RAW((trie), data, 0, (c)); \
 244     } else if(!U16_IS_SURROGATE_LEAD(c)) { \
 245         /* trail surrogate */ \
 246         if((start)!=(src) && U16_IS_LEAD((c2)=*((src)-1))) { \
 247             --(src); \
 248             (result)=(c); (c)=(c2); (c2)=(UChar)(result); /* swap c, c2 */ \
 249             _UTRIE_GET_FROM_PAIR((trie), data, (c), (c2), (result), resultType); \
 250         } else { \
 251             /* unpaired trail surrogate code point */ \
 252             (c2)=0; \
 253             (result)=_UTRIE_GET_RAW((trie), data, 0, (c)); \
 254         } \
 255     } else { \
 256         /* unpaired lead surrogate code point */ \
 257         (c2)=0; \
 258         (result)=_UTRIE_GET_RAW((trie), data, UTRIE_LEAD_INDEX_DISP, (c)); \
 259     } \
 260 }
 261
 262 /* Public UTrie API ---------------------------------------------------------*/
 263
 264 /**
 265  * Get a pointer to the contiguous part of the data array
 266  * for the Latin-1 range (U+0000..U+00ff).
 267  * Must be used only if the Latin-1 range is in fact linear
 268  * (trie->isLatin1Linear).
 269  *
 270  * @param trie (const UTrie *, in) a pointer to the runtime trie structure
 271  * @return (const uint16_t *) pointer to values for Latin-1 code points
 272  */
 273 #define UTRIE_GET16_LATIN1(trie) ((trie)->index+(trie)->indexLength+UTRIE_DATA_BLOCK_LENGTH)
 274
 275 /**
 276  * Get a pointer to the contiguous part of the data array
 277  * for the Latin-1 range (U+0000..U+00ff).
 278  * Must be used only if the Latin-1 range is in fact linear
 279  * (trie->isLatin1Linear).
 280  *
 281  * @param trie (const UTrie *, in) a pointer to the runtime trie structure
 282  * @return (const uint32_t *) pointer to values for Latin-1 code points
 283  */
 284 #define UTRIE_GET32_LATIN1(trie) ((trie)->data32+UTRIE_DATA_BLOCK_LENGTH)
 285
 286 /**
 287  * Get a 16-bit trie value from a BMP code point (UChar, <=U+ffff).
 288  * c16 may be a lead surrogate, which may have a value including a folding offset.
 289  *
 290  * @param trie (const UTrie *, in) a pointer to the runtime trie structure
 291  * @param c16 (UChar, in) the input BMP code point
 292  * @return (uint16_t) trie lookup result
 293  */
 294 #define UTRIE_GET16_FROM_LEAD(trie, c16) _UTRIE_GET_RAW(trie, index, 0, c16)
 295
 296 /**
 297  * Get a 32-bit trie value from a BMP code point (UChar, <=U+ffff).
 298  * c16 may be a lead surrogate, which may have a value including a folding offset.
 299  *
 300  * @param trie (const UTrie *, in) a pointer to the runtime trie structure
 301  * @param c16 (UChar, in) the input BMP code point
 302  * @return (uint32_t) trie lookup result
 303  */
 304 #define UTRIE_GET32_FROM_LEAD(trie, c16) _UTRIE_GET_RAW(trie, data32, 0, c16)
 305
 306 /**
 307  * Get a 16-bit trie value from a BMP code point (UChar, <=U+ffff).
 308  * Even lead surrogate code points are treated as normal code points,
 309  * with unfolded values that may differ from _FROM_LEAD() macro results for them.
 310  *
 311  * @param trie (const UTrie *, in) a pointer to the runtime trie structure
 312  * @param c16 (UChar, in) the input BMP code point
 313  * @return (uint16_t) trie lookup result
 314  */
 315 #define UTRIE_GET16_FROM_BMP(trie, c16) _UTRIE_GET_FROM_BMP(trie, index, c16)
 316
 317 /**
 318  * Get a 32-bit trie value from a BMP code point (UChar, <=U+ffff).
 319  * Even lead surrogate code points are treated as normal code points,
 320  * with unfolded values that may differ from _FROM_LEAD() macro results for them.
 321  *
 322  * @param trie (const UTrie *, in) a pointer to the runtime trie structure
 323  * @param c16 (UChar, in) the input BMP code point
 324  * @return (uint32_t) trie lookup result
 325  */
 326 #define UTRIE_GET32_FROM_BMP(trie, c16) _UTRIE_GET_FROM_BMP(trie, data32, c16)
 327
 328 /**
 329  * Get a 16-bit trie value from a code point.
 330  * Even lead surrogate code points are treated as normal code points,
 331  * with unfolded values that may differ from _FROM_LEAD() macro results for them.
 332  *
 333  * @param trie (const UTrie *, in) a pointer to the runtime trie structure
 334  * @param c32 (UChar32, in) the input code point
 335  * @param result (uint16_t, out) uint16_t variable for the trie lookup result
 336  */
 337 #define UTRIE_GET16(trie, c32, result) _UTRIE_GET(trie, index, c32, result, uint16_t)
 338
 339 /**
 340  * Get a 32-bit trie value from a code point.
 341  * Even lead surrogate code points are treated as normal code points,
 342  * with unfolded values that may differ from _FROM_LEAD() macro results for them.
 343  *
 344  * @param trie (const UTrie *, in) a pointer to the runtime trie structure
 345  * @param c32 (UChar32, in) the input code point
 346  * @param result (uint32_t, out) uint32_t variable for the trie lookup result
 347  */
 348 #define UTRIE_GET32(trie, c32, result) _UTRIE_GET(trie, data32, c32, result, uint32_t)
 349
 350 /**
 351  * Get the next code point (c, c2), post-increment src,
 352  * and get a 16-bit value from the trie.
 353  *
 354  * @param trie (const UTrie *, in) a pointer to the runtime trie structure
 355  * @param src (const UChar *, in/out) the source text pointer
 356  * @param limit (const UChar *, in) the limit pointer for the text, or NULL
 357  * @param c (UChar, out) variable for the BMP or lead code unit
 358  * @param c2 (UChar, out) variable for 0 or the trail code unit
 359  * @param result (uint16_t, out) uint16_t variable for the trie lookup result
 360  */
 361 #define UTRIE_NEXT16(trie, src, limit, c, c2, result) _UTRIE_NEXT(trie, index, src, limit, c, c2, result, uint16_t)
 362
 363 /**
 364  * Get the next code point (c, c2), post-increment src,
 365  * and get a 32-bit value from the trie.
 366  *
 367  * @param trie (const UTrie *, in) a pointer to the runtime trie structure
 368  * @param src (const UChar *, in/out) the source text pointer
 369  * @param limit (const UChar *, in) the limit pointer for the text, or NULL
 370  * @param c (UChar, out) variable for the BMP or lead code unit
 371  * @param c2 (UChar, out) variable for 0 or the trail code unit
 372  * @param result (uint32_t, out) uint32_t variable for the trie lookup result
 373  */
 374 #define UTRIE_NEXT32(trie, src, limit, c, c2, result) _UTRIE_NEXT(trie, data32, src, limit, c, c2, result, uint32_t)
 375
 376 /**
 377  * Get the previous code point (c, c2), pre-decrement src,
 378  * and get a 16-bit value from the trie.
 379  *
 380  * @param trie (const UTrie *, in) a pointer to the runtime trie structure
 381  * @param start (const UChar *, in) the start pointer for the text, or NULL
 382  * @param src (const UChar *, in/out) the source text pointer
 383  * @param c (UChar, out) variable for the BMP or lead code unit
 384  * @param c2 (UChar, out) variable for 0 or the trail code unit
 385  * @param result (uint16_t, out) uint16_t variable for the trie lookup result
 386  */
 387 #define UTRIE_PREVIOUS16(trie, start, src, c, c2, result) _UTRIE_PREVIOUS(trie, index, start, src, c, c2, result, uint16_t)
 388
 389 /**
 390  * Get the previous code point (c, c2), pre-decrement src,
 391  * and get a 32-bit value from the trie.
 392  *
 393  * @param trie (const UTrie *, in) a pointer to the runtime trie structure
 394  * @param start (const UChar *, in) the start pointer for the text, or NULL
 395  * @param src (const UChar *, in/out) the source text pointer
 396  * @param c (UChar, out) variable for the BMP or lead code unit
 397  * @param c2 (UChar, out) variable for 0 or the trail code unit
 398  * @param result (uint32_t, out) uint32_t variable for the trie lookup result
 399  */
 400 #define UTRIE_PREVIOUS32(trie, start, src, c, c2, result) _UTRIE_PREVIOUS(trie, data32, start, src, c, c2, result, uint32_t)
 401
 402 /**
 403  * Get a 16-bit trie value from a pair of surrogates.
 404  *
 405  * @param trie (const UTrie *, in) a pointer to the runtime trie structure
 406  * @param c (UChar, in) a lead surrogate
 407  * @param c2 (UChar, in) a trail surrogate
 408  * @param result (uint16_t, out) uint16_t variable for the trie lookup result
 409  */
 410 #define UTRIE_GET16_FROM_PAIR(trie, c, c2, result) _UTRIE_GET_FROM_PAIR(trie, index, c, c2, result, uint16_t)
 411
 412 /**
 413  * Get a 32-bit trie value from a pair of surrogates.
 414  *
 415  * @param trie (const UTrie *, in) a pointer to the runtime trie structure
 416  * @param c (UChar, in) a lead surrogate
 417  * @param c2 (UChar, in) a trail surrogate
 418  * @param result (uint32_t, out) uint32_t variable for the trie lookup result
 419  */
 420 #define UTRIE_GET32_FROM_PAIR(trie, c, c2, result) _UTRIE_GET_FROM_PAIR(trie, data32, c, c2, result, uint32_t)
 421
 422 /**
 423  * Get a 16-bit trie value from a folding offset (from the value of a lead surrogate)
 424  * and a trail surrogate.
 425  *
 426  * @param trie (const UTrie *, in) a pointer to the runtime trie structure
 427  * @param offset (int32_t, in) the folding offset from the value of a lead surrogate
 428  * @param c2 (UChar, in) a trail surrogate (only the 10 low bits are significant)
 429  * @return (uint16_t) trie lookup result
 430  */
 431 #define UTRIE_GET16_FROM_OFFSET_TRAIL(trie, offset, c2) _UTRIE_GET_RAW(trie, index, offset, (c2)&0x3ff)
 432
 433 /**
 434  * Get a 32-bit trie value from a folding offset (from the value of a lead surrogate)
 435  * and a trail surrogate.
 436  *
 437  * @param trie (const UTrie *, in) a pointer to the runtime trie structure
 438  * @param offset (int32_t, in) the folding offset from the value of a lead surrogate
 439  * @param c2 (UChar, in) a trail surrogate (only the 10 low bits are significant)
 440  * @return (uint32_t) trie lookup result
 441  */
 442 #define UTRIE_GET32_FROM_OFFSET_TRAIL(trie, offset, c2) _UTRIE_GET_RAW(trie, data32, offset, (c2)&0x3ff)
 443
 444 /* enumeration callback types */
 445
 446 /**
 447  * Callback from utrie_enum(), extracts a uint32_t value from a
 448  * trie value. This value will be passed on to the UTrieEnumRange function.
 449  *
 450  * @param context an opaque pointer, as passed into utrie_enum()
 451  * @param value a value from the trie
 452  * @return the value that is to be passed on to the UTrieEnumRange function
 453  */
 454 typedef uint32_t U_CALLCONV
 455 UTrieEnumValue(const void *context, uint32_t value);
 456
 457 /**
 458  * Callback from utrie_enum(), is called for each contiguous range
 459  * of code points with the same value as retrieved from the trie and
 460  * transformed by the UTrieEnumValue function.
 461  *
 462  * The callback function can stop the enumeration by returning FALSE.
 463  *
 464  * @param context an opaque pointer, as passed into utrie_enum()
 465  * @param start the first code point in a contiguous range with value
 466  * @param limit one past the last code point in a contiguous range with value
 467  * @param value the value that is set for all code points in [start..limit[
 468  * @return FALSE to stop the enumeration
 469  */
 470 typedef UBool U_CALLCONV
 471 UTrieEnumRange(const void *context, UChar32 start, UChar32 limit, uint32_t value);
 472
 473 /**
 474  * Enumerate efficiently all values in a trie.
 475  * For each entry in the trie, the value to be delivered is passed through
 476  * the UTrieEnumValue function.
 477  * The value is unchanged if that function pointer is NULL.
 478  *
 479  * For each contiguous range of code points with a given value,
 480  * the UTrieEnumRange function is called.
 481  *
 482  * @param trie a pointer to the runtime trie structure
 483  * @param enumValue a pointer to a function that may transform the trie entry value,
 484  *                  or NULL if the values from the trie are to be used directly
 485  * @param enumRange a pointer to a function that is called for each contiguous range
 486  *                  of code points with the same value
 487  * @param context an opaque pointer that is passed on to the callback functions
 488  */
 489 U_CAPI void U_EXPORT2
 490 utrie_enum(const UTrie *trie,
 491            UTrieEnumValue *enumValue, UTrieEnumRange *enumRange, const void *context);
 492
 493 /**
 494  * Unserialize a trie from 32-bit-aligned memory.
 495  * Inverse of utrie_serialize().
 496  * Fills the UTrie runtime trie structure with the settings for the trie data.
 497  *
 498  * @param trie a pointer to the runtime trie structure
 499  * @param data a pointer to 32-bit-aligned memory containing trie data
 500  * @param length the number of bytes available at data
 501  * @param pErrorCode an in/out ICU UErrorCode
 502  * @return the number of bytes at data taken up by the trie data
 503  */
 504 U_CAPI int32_t U_EXPORT2
 505 utrie_unserialize(UTrie *trie, const void *data, int32_t length, UErrorCode *pErrorCode);
 506
 507 /**
 508  * "Unserialize" a dummy trie.
 509  * A dummy trie is an empty runtime trie, used when a real data trie cannot
 510  * be loaded.
 511  *
 512  * The input memory is filled so that the trie always returns the initialValue,
 513  * or the leadUnitValue for lead surrogate code points.
 514  * The Latin-1 part is always set up to be linear.
 515  *
 516  * @param trie a pointer to the runtime trie structure
 517  * @param data a pointer to 32-bit-aligned memory to be filled with the dummy trie data
 518  * @param length the number of bytes available at data (recommended to use UTRIE_DUMMY_SIZE)
 519  * @param initialValue the initial value that is set for all code points
 520  * @param leadUnitValue the value for lead surrogate code _units_ that do not
 521  *                      have associated supplementary data
 522  * @param pErrorCode an in/out ICU UErrorCode
 523  *
 524  * @see UTRIE_DUMMY_SIZE
 525  * @see utrie_open
 526  */
 527 U_CAPI int32_t U_EXPORT2
 528 utrie_unserializeDummy(UTrie *trie,
 529                        void *data, int32_t length,
 530                        uint32_t initialValue, uint32_t leadUnitValue,
 531                        UBool make16BitTrie,
 532                        UErrorCode *pErrorCode);
 533
 534 /**
 535  * Default implementation for UTrie.getFoldingOffset, set automatically by
 536  * utrie_unserialize().
 537  * Simply returns the lead surrogate's value itself - which is the inverse
 538  * of the default folding function used by utrie_serialize().
 539  * Exported for static const UTrie structures.
 540  *
 541  * @see UTrieGetFoldingOffset
 542  */
 543 U_CAPI int32_t U_EXPORT2
 544 utrie_defaultGetFoldingOffset(uint32_t data);
 545
 546 /* Building a trie ----------------------------------------------------------*/
 547
 548 /**
 549  * Build-time trie structure.
 550  * Opaque definition, here only to make fillIn parameters possible
 551  * for utrie_open() and utrie_clone().
 552  */
 553 struct UNewTrie {
 554     /**
 555      * Index values at build-time are 32 bits wide for easier processing.
 556      * Bit 31 is set if the data block is used by multiple index values (from utrie_setRange()).
 557      */
 558     int32_t index[UTRIE_MAX_INDEX_LENGTH+UTRIE_SURROGATE_BLOCK_COUNT];
 559     uint32_t *data;
 560
 561     uint32_t leadUnitValue;
 562     int32_t indexLength, dataCapacity, dataLength;
 563     UBool isAllocated, isDataAllocated;
 564     UBool isLatin1Linear, isCompacted;
 565
 566     /**
 567      * Map of adjusted indexes, used in utrie_compact().
 568      * Maps from original indexes to new ones.
 569      */
 570     int32_t map[UTRIE_MAX_BUILD_TIME_DATA_LENGTH>>UTRIE_SHIFT];
 571 };
 572
 573 typedef struct UNewTrie UNewTrie;
 574
 575 /**
 576  * Build-time trie callback function, used with utrie_serialize().
 577  * This function calculates a lead surrogate's value including a folding offset
 578  * from the 1024 supplementary code points [start..start+1024[ .
 579  * It is U+10000 <= start <= U+10fc00 and (start&0x3ff)==0.
 580  *
 581  * The folding offset is provided by the caller.
 582  * It is offset=UTRIE_BMP_INDEX_LENGTH+n*UTRIE_SURROGATE_BLOCK_COUNT with n=0..1023.
 583  * Instead of the offset itself, n can be stored in 10 bits -
 584  * or fewer if it can be assumed that few lead surrogates have associated data.
 585  *
 586  * The returned value must be
 587  * - not zero if and only if there is relevant data
 588  *   for the corresponding 1024 supplementary code points
 589  * - such that UTrie.getFoldingOffset(UNewTrieGetFoldedValue(..., offset))==offset
 590  *
 591  * @return a folded value, or 0 if there is no relevant data for the lead surrogate.
 592  */
 593 typedef uint32_t U_CALLCONV
 594 UNewTrieGetFoldedValue(UNewTrie *trie, UChar32 start, int32_t offset);
 595
 596 /**
 597  * Open a build-time trie structure.
 598  * The size of the build-time data array is specified to avoid allocating a large
 599  * array in all cases. The array itself can also be passed in.
 600  *
 601  * Although the trie is never fully expanded to a linear array, especially when
 602  * utrie_setRange32() is used, the data array could be large during build time.
 603  * The maximum length is
 604  * UTRIE_MAX_BUILD_TIME_DATA_LENGTH=0x110000+UTRIE_DATA_BLOCK_LENGTH+0x400.
 605  * (Number of Unicode code points + one all-initial-value block +
 606  *  possible duplicate entries for 1024 lead surrogates.)
 607  * (UTRIE_DATA_BLOCK_LENGTH<=0x200 in all cases.)
 608  *
 609  * @param fillIn a pointer to a UNewTrie structure to be initialized (will not be released), or
 610  *               NULL if one is to be allocated
 611  * @param aliasData a pointer to a data array to be used (will not be released), or
 612  *                  NULL if one is to be allocated
 613  * @param maxDataLength the capacity of aliasData (if not NULL) or
 614  *                      the length of the data array to be allocated
 615  * @param initialValue the initial value that is set for all code points
 616  * @param leadUnitValue the value for lead surrogate code _units_ that do not
 617  *                      have associated supplementary data
 618  * @param latin1Linear a flag indicating whether the Latin-1 range is to be allocated and
 619  *                     kept in a linear, contiguous part of the data array
 620  * @return a pointer to the initialized fillIn or the allocated and initialized new UNewTrie
 621  */
 622 U_CAPI UNewTrie * U_EXPORT2
 623 utrie_open(UNewTrie *fillIn,
 624            uint32_t *aliasData, int32_t maxDataLength,
 625            uint32_t initialValue, uint32_t leadUnitValue,
 626            UBool latin1Linear);
 627
 628 /**
 629  * Clone a build-time trie structure with all entries.
 630  *
 631  * @param fillIn like in utrie_open()
 632  * @param other the build-time trie structure to clone
 633  * @param aliasData like in utrie_open(),
 634  *                  used if aliasDataLength>=(capacity of other's data array)
 635  * @param aliasDataLength the length of aliasData
 636  * @return a pointer to the initialized fillIn or the allocated and initialized new UNewTrie
 637  */
 638 U_CAPI UNewTrie * U_EXPORT2
 639 utrie_clone(UNewTrie *fillIn, const UNewTrie *other, uint32_t *aliasData, int32_t aliasDataLength);
 640
 641 /**
 642  * Close a build-time trie structure, and release memory
 643  * that was allocated by utrie_open() or utrie_clone().
 644  *
 645  * @param trie the build-time trie
 646  */
 647 U_CAPI void U_EXPORT2
 648 utrie_close(UNewTrie *trie);
 649
 650 /**
 651  * Get the data array of a build-time trie.
 652  * The data may be modified, but entries that are equal before
 653  * must still be equal after modification.
 654  *
 655  * @param trie the build-time trie
 656  * @param pLength (out) a pointer to a variable that receives the number
 657  *                of entries in the data array
 658  * @return the data array
 659  */
 660 U_CAPI uint32_t * U_EXPORT2
 661 utrie_getData(UNewTrie *trie, int32_t *pLength);
 662
 663 /**
 664  * Set a value for a code point.
 665  *
 666  * @param trie the build-time trie
 667  * @param c the code point
 668  * @param value the value
 669  * @return FALSE if a failure occurred (illegal argument or data array overrun)
 670  */
 671 U_CAPI UBool U_EXPORT2
 672 utrie_set32(UNewTrie *trie, UChar32 c, uint32_t value);
 673
 674 /**
 675  * Get a value from a code point as stored in the build-time trie.
 676  *
 677  * @param trie the build-time trie
 678  * @param c the code point
 679  * @param pInBlockZero if not NULL, then *pInBlockZero is set to TRUE
 680  *                     iff the value is retrieved from block 0;
 681  *                     block 0 is the all-initial-value initial block
 682  * @return the value
 683  */
 684 U_CAPI uint32_t U_EXPORT2
 685 utrie_get32(UNewTrie *trie, UChar32 c, UBool *pInBlockZero);
 686
 687 /**
 688  * Set a value in a range of code points [start..limit[.
 689  * All code points c with start<=c<limit will get the value if
 690  * overwrite is TRUE or if the old value is 0.
 691  *
 692  * @param trie the build-time trie
 693  * @param start the first code point to get the value
 694  * @param limit one past the last code point to get the value
 695  * @param value the value
 696  * @param overwrite flag for whether old non-initial values are to be overwritten
 697  * @return FALSE if a failure occurred (illegal argument or data array overrun)
 698  */
 699 U_CAPI UBool U_EXPORT2
 700 utrie_setRange32(UNewTrie *trie, UChar32 start, UChar32 limit, uint32_t value, UBool overwrite);
 701
 702 /**
 703  * Compact the build-time trie after all values are set, and then
 704  * serialize it into 32-bit aligned memory.
 705  *
 706  * After this, the trie can only be serizalized again and/or closed;
 707  * no further values can be added.
 708  *
 709  * @see utrie_unserialize()
 710  *
 711  * @param trie the build-time trie
 712  * @param data a pointer to 32-bit-aligned memory for the trie data
 713  * @param capacity the number of bytes available at data
 714  * @param getFoldedValue a callback function that calculates the value for
 715  *                       a lead surrogate from all of its supplementary code points
 716  *                       and the folding offset;
 717  *                       if NULL, then a default function is used which returns just
 718  *                       the input offset when there are any non-initial-value entries
 719  * @param reduceTo16Bits flag for whether the values are to be reduced to a
 720  *                       width of 16 bits for serialization and runtime
 721  * @param pErrorCode a UErrorCode argument; among other possible error codes:
 722  * - U_BUFFER_OVERFLOW_ERROR if the data storage block is too small for serialization
 723  * - U_MEMORY_ALLOCATION_ERROR if the trie data array is too small
 724  * - U_INDEX_OUTOFBOUNDS_ERROR if the index or data arrays are too long after compaction for serialization
 725  *
 726  * @return the number of bytes written for the trie
 727  */
 728 U_CAPI int32_t U_EXPORT2
 729 utrie_serialize(UNewTrie *trie, void *data, int32_t capacity,
 730                 UNewTrieGetFoldedValue *getFoldedValue,
 731                 UBool reduceTo16Bits,
 732                 UErrorCode *pErrorCode);
 733
 734 /* serialization ------------------------------------------------------------ */
 735
 736 // UTrie signature values, in platform endianness and opposite endianness.
 737 // The UTrie signature ASCII byte values spell "Trie".
 738 #define UTRIE_SIG       0x54726965
 739 #define UTRIE_OE_SIG    0x65697254
 740
 741 /**
 742  * Trie data structure in serialized form:
 743  *
 744  * UTrieHeader header;
 745  * uint16_t index[header.indexLength];
 746  * uint16_t data[header.dataLength];
 747  * @internal
 748  */
 749 typedef struct UTrieHeader {
 750     /** "Trie" in big-endian US-ASCII (0x54726965) */
 751     uint32_t signature;
 752
 753     /**
 754      * options bit field:
 755      *     9    1=Latin-1 data is stored linearly at data+UTRIE_DATA_BLOCK_LENGTH
 756      *     8    0=16-bit data, 1=32-bit data
 757      *  7..4    UTRIE_INDEX_SHIFT   // 0..UTRIE_SHIFT
 758      *  3..0    UTRIE_SHIFT         // 1..9
 759      */
 760     uint32_t options;
 761
 762     /** indexLength is a multiple of UTRIE_SURROGATE_BLOCK_COUNT */
 763     int32_t indexLength;
 764
 765     /** dataLength>=UTRIE_DATA_BLOCK_LENGTH */
 766     int32_t dataLength;
 767 } UTrieHeader;
 768
 769 /**
 770  * Constants for use with UTrieHeader.options.
 771  * @internal
 772  */
 773 enum {
 774     /** Mask to get the UTRIE_SHIFT value from options. */
 775     UTRIE_OPTIONS_SHIFT_MASK=0xf,
 776
 777     /** Shift options right this much to get the UTRIE_INDEX_SHIFT value. */
 778     UTRIE_OPTIONS_INDEX_SHIFT=4,
 779
 780     /** If set, then the data (stage 2) array is 32 bits wide. */
 781     UTRIE_OPTIONS_DATA_IS_32_BIT=0x100,
 782
 783     /**
 784      * If set, then Latin-1 data (for U+0000..U+00ff) is stored in the data (stage 2) array
 785      * as a simple, linear array at data+UTRIE_DATA_BLOCK_LENGTH.
 786      */
 787     UTRIE_OPTIONS_LATIN1_IS_LINEAR=0x200
 788 };
 789
 790 U_CDECL_END
 791
 792 #endif