icuSources/common/ubidiimp.h

   1 /*
   2 ******************************************************************************
   3 *
   4 *   Copyright (C) 1999-2007, International Business Machines
   5 *   Corporation and others.  All Rights Reserved.
   6 *
   7 ******************************************************************************
   8 *   file name:  ubidiimp.h
   9 *   encoding:   US-ASCII
  10 *   tab size:   8 (not used)
  11 *   indentation:4
  12 *
  13 *   created on: 1999aug06
  14 *   created by: Markus W. Scherer, updated by Matitiahu Allouche
  15 */
  16
  17 #ifndef UBIDIIMP_H
  18 #define UBIDIIMP_H
  19
  20 /* set import/export definitions */
  21 #ifdef U_COMMON_IMPLEMENTATION
  22
  23 #include "unicode/utypes.h"
  24 #include "unicode/uchar.h"
  25 #include "ubidi_props.h"
  26
  27 /* miscellaneous definitions ---------------------------------------------- */
  28
  29 typedef uint8_t DirProp;
  30 typedef uint32_t Flags;
  31
  32 /*  Comparing the description of the BiDi algorithm with this implementation
  33     is easier with the same names for the BiDi types in the code as there.
  34     See UCharDirection in uchar.h .
  35 */
  36 enum {
  37     L=  U_LEFT_TO_RIGHT,
  38     R=  U_RIGHT_TO_LEFT,
  39     EN= U_EUROPEAN_NUMBER,
  40     ES= U_EUROPEAN_NUMBER_SEPARATOR,
  41     ET= U_EUROPEAN_NUMBER_TERMINATOR,
  42     AN= U_ARABIC_NUMBER,
  43     CS= U_COMMON_NUMBER_SEPARATOR,
  44     B=  U_BLOCK_SEPARATOR,
  45     S=  U_SEGMENT_SEPARATOR,
  46     WS= U_WHITE_SPACE_NEUTRAL,
  47     ON= U_OTHER_NEUTRAL,
  48     LRE=U_LEFT_TO_RIGHT_EMBEDDING,
  49     LRO=U_LEFT_TO_RIGHT_OVERRIDE,
  50     AL= U_RIGHT_TO_LEFT_ARABIC,
  51     RLE=U_RIGHT_TO_LEFT_EMBEDDING,
  52     RLO=U_RIGHT_TO_LEFT_OVERRIDE,
  53     PDF=U_POP_DIRECTIONAL_FORMAT,
  54     NSM=U_DIR_NON_SPACING_MARK,
  55     BN= U_BOUNDARY_NEUTRAL,
  56     dirPropCount
  57 };
  58
  59 /*
  60  * Sometimes, bit values are more appropriate
  61  * to deal with directionality properties.
  62  * Abbreviations in these macro names refer to names
  63  * used in the BiDi algorithm.
  64  */
  65 #define DIRPROP_FLAG(dir) (1UL<<(dir))
  66
  67 /* special flag for multiple runs from explicit embedding codes */
  68 #define DIRPROP_FLAG_MULTI_RUNS (1UL<<31)
  69
  70 /* are there any characters that are LTR or RTL? */
  71 #define MASK_LTR (DIRPROP_FLAG(L)|DIRPROP_FLAG(EN)|DIRPROP_FLAG(AN)|DIRPROP_FLAG(LRE)|DIRPROP_FLAG(LRO))
  72 #define MASK_RTL (DIRPROP_FLAG(R)|DIRPROP_FLAG(AL)|DIRPROP_FLAG(RLE)|DIRPROP_FLAG(RLO))
  73 #define MASK_R_AL (DIRPROP_FLAG(R)|DIRPROP_FLAG(AL))
  74
  75 /* explicit embedding codes */
  76 #define MASK_LRX (DIRPROP_FLAG(LRE)|DIRPROP_FLAG(LRO))
  77 #define MASK_RLX (DIRPROP_FLAG(RLE)|DIRPROP_FLAG(RLO))
  78 #define MASK_OVERRIDE (DIRPROP_FLAG(LRO)|DIRPROP_FLAG(RLO))
  79
  80 #define MASK_EXPLICIT (MASK_LRX|MASK_RLX|DIRPROP_FLAG(PDF))
  81 #define MASK_BN_EXPLICIT (DIRPROP_FLAG(BN)|MASK_EXPLICIT)
  82
  83 /* paragraph and segment separators */
  84 #define MASK_B_S (DIRPROP_FLAG(B)|DIRPROP_FLAG(S))
  85
  86 /* all types that are counted as White Space or Neutral in some steps */
  87 #define MASK_WS (MASK_B_S|DIRPROP_FLAG(WS)|MASK_BN_EXPLICIT)
  88 #define MASK_N (DIRPROP_FLAG(ON)|MASK_WS)
  89
  90 /* all types that are included in a sequence of European Terminators for (W5) */
  91 #define MASK_ET_NSM_BN (DIRPROP_FLAG(ET)|DIRPROP_FLAG(NSM)|MASK_BN_EXPLICIT)
  92
  93 /* types that are neutrals or could becomes neutrals in (Wn) */
  94 #define MASK_POSSIBLE_N (DIRPROP_FLAG(CS)|DIRPROP_FLAG(ES)|DIRPROP_FLAG(ET)|MASK_N)
  95
  96 /*
  97  * These types may be changed to "e",
  98  * the embedding type (L or R) of the run,
  99  * in the BiDi algorithm (N2)
 100  */
 101 #define MASK_EMBEDDING (DIRPROP_FLAG(NSM)|MASK_POSSIBLE_N)
 102
 103 /* the dirProp's L and R are defined to 0 and 1 values in UCharDirection */
 104 #define GET_LR_FROM_LEVEL(level) ((DirProp)((level)&1))
 105
 106 #define IS_DEFAULT_LEVEL(level) ((level)>=0xfe)
 107
 108 /*
 109  * The following bit is ORed to the property of characters in paragraphs
 110  * with contextual RTL direction when paraLevel is contextual.
 111  */
 112 #define CONTEXT_RTL 0x80
 113 #define NO_CONTEXT_RTL(dir) ((dir)&~CONTEXT_RTL)
 114 /*
 115  * The following is a variant of DIRPROP_FLAG which ignores the CONTEXT_RTL bit.
 116  */
 117 #define DIRPROP_FLAG_NC(dir) (1UL<<(NO_CONTEXT_RTL(dir)))
 118
 119 #define GET_PARALEVEL(ubidi, index) \
 120             (UBiDiLevel)((ubidi)->defaultParaLevel ? (ubidi)->dirProps[index]>>7 \
 121                                                    : (ubidi)->paraLevel)
 122
 123 /* Paragraph type for multiple paragraph support ---------------------------- */
 124 typedef int32_t Para;
 125
 126 #define CR  0x000D
 127 #define LF  0x000A
 128
 129 /* Run structure for reordering --------------------------------------------- */
 130 enum {
 131     LRM_BEFORE=1,
 132     LRM_AFTER=2,
 133     RLM_BEFORE=4,
 134     RLM_AFTER=8
 135 };
 136
 137 typedef struct Run {
 138     int32_t logicalStart,   /* first character of the run; b31 indicates even/odd level */
 139             visualLimit,    /* last visual position of the run +1 */
 140             insertRemove;   /* if >0, flags for inserting LRM/RLM before/after run,
 141                                if <0, count of bidi controls within run            */
 142 } Run;
 143
 144 /* in a Run, logicalStart will get this bit set if the run level is odd */
 145 #define INDEX_ODD_BIT (1UL<<31)
 146
 147 #define MAKE_INDEX_ODD_PAIR(index, level) ((index)|((int32_t)(level)<<31))
 148 #define ADD_ODD_BIT_FROM_LEVEL(x, level)  ((x)|=((int32_t)(level)<<31))
 149 #define REMOVE_ODD_BIT(x)                 ((x)&=~INDEX_ODD_BIT)
 150
 151 #define GET_INDEX(x)   ((x)&~INDEX_ODD_BIT)
 152 #define GET_ODD_BIT(x) ((uint32_t)(x)>>31)
 153 #define IS_ODD_RUN(x)  ((UBool)(((x)&INDEX_ODD_BIT)!=0))
 154 #define IS_EVEN_RUN(x) ((UBool)(((x)&INDEX_ODD_BIT)==0))
 155
 156 U_CFUNC UBool
 157 ubidi_getRuns(UBiDi *pBiDi, UErrorCode *pErrorCode);
 158
 159 /** BiDi control code points */
 160 enum {
 161     ZWNJ_CHAR=0x200c,
 162     ZWJ_CHAR,
 163     LRM_CHAR,
 164     RLM_CHAR,
 165     LRE_CHAR=0x202a,
 166     RLE_CHAR,
 167     PDF_CHAR,
 168     LRO_CHAR,
 169     RLO_CHAR
 170 };
 171
 172 #define IS_BIDI_CONTROL_CHAR(c) (((uint32_t)(c)&0xfffffffc)==ZWNJ_CHAR || (uint32_t)((c)-LRE_CHAR)<5)
 173
 174 /* InsertPoints structure for noting where to put BiDi marks ---------------- */
 175
 176 typedef struct Point {
 177     int32_t pos;            /* position in text */
 178     int32_t flag;           /* flag for LRM/RLM, before/after */
 179 } Point;
 180
 181 typedef struct InsertPoints {
 182     int32_t capacity;       /* number of points allocated */
 183     int32_t size;           /* number of points used */
 184     int32_t confirmed;      /* number of points confirmed */
 185     UErrorCode errorCode;   /* for eventual memory shortage */
 186     Point *points;          /* pointer to array of points */
 187 } InsertPoints;
 188
 189
 190 /* UBiDi structure ----------------------------------------------------------- */
 191
 192 struct UBiDi {
 193     /* pointer to parent paragraph object (pointer to self if this object is
 194      * a paragraph object); set to NULL in a newly opened object; set to a
 195      * real value after a successful execution of ubidi_setPara or ubidi_setLine
 196      */
 197     const UBiDi * pParaBiDi;
 198
 199     const UBiDiProps *bdp;
 200
 201     /* alias pointer to the current text */
 202     const UChar *text;
 203
 204     /* length of the current text */
 205     int32_t originalLength;
 206
 207     /* if the UBIDI_OPTION_STREAMING option is set, this is the length
 208      * of text actually processed by ubidi_setPara, which may be shorter than
 209      * the original length.
 210      * Otherwise, it is identical to the original length.
 211      */
 212     int32_t length;
 213
 214     /* if the UBIDI_OPTION_REMOVE_CONTROLS option is set, and/or
 215      * marks are allowed to be inserted in one of the reordering mode, the
 216      * length of the result string may be different from the processed length.
 217      */
 218     int32_t resultLength;
 219
 220     /* memory sizes in bytes */
 221     int32_t dirPropsSize, levelsSize, parasSize, runsSize;
 222
 223     /* allocated memory */
 224     DirProp *dirPropsMemory;
 225     UBiDiLevel *levelsMemory;
 226     Para *parasMemory;
 227     Run *runsMemory;
 228
 229     /* indicators for whether memory may be allocated after ubidi_open() */
 230     UBool mayAllocateText, mayAllocateRuns;
 231
 232     /* arrays with one value per text-character */
 233     const DirProp *dirProps;
 234     UBiDiLevel *levels;
 235
 236     /* are we performing an approximation of the "inverse BiDi" algorithm? */
 237     UBool isInverse;
 238
 239     /* are we using the basic algorithm or its variation? */
 240     UBiDiReorderingMode reorderingMode;
 241
 242     /* UBIDI_REORDER_xxx values must be ordered so that all the regular
 243      * logical to visual modes come first, and all inverse BiDi modes
 244      * come last.
 245      */
 246     #define UBIDI_REORDER_LAST_LOGICAL_TO_VISUAL    UBIDI_REORDER_NUMBERS_SPECIAL
 247
 248     /* bitmask for reordering options */
 249     uint32_t reorderingOptions;
 250
 251     /* must block separators receive level 0? */
 252     UBool orderParagraphsLTR;
 253
 254     /* the paragraph level */
 255     UBiDiLevel paraLevel;
 256     /* original paraLevel when contextual */
 257     /* must be one of UBIDI_DEFAULT_xxx or 0 if not contextual */
 258     UBiDiLevel defaultParaLevel;
 259
 260     /* the following is set in ubidi_setPara, used in processPropertySeq */
 261     const struct ImpTabPair * pImpTabPair;  /* pointer to levels state table pair */
 262
 263     /* the overall paragraph or line directionality - see UBiDiDirection */
 264     UBiDiDirection direction;
 265
 266     /* flags is a bit set for which directional properties are in the text */
 267     Flags flags;
 268
 269     /* lastArabicPos is index to the last AL in the text, -1 if none */
 270     int32_t lastArabicPos;
 271
 272     /* characters after trailingWSStart are WS and are */
 273     /* implicitly at the paraLevel (rule (L1)) - levels may not reflect that */
 274     int32_t trailingWSStart;
 275
 276     /* fields for paragraph handling */
 277     int32_t paraCount;                  /* set in getDirProps() */
 278     Para *paras;                        /* limits of paragraphs, filled in
 279                             ResolveExplicitLevels() or CheckExplicitLevels() */
 280
 281     /* for single paragraph text, we only need a tiny array of paras (no malloc()) */
 282     Para simpleParas[1];
 283
 284     /* fields for line reordering */
 285     int32_t runCount;     /* ==-1: runs not set up yet */
 286     Run *runs;
 287
 288     /* for non-mixed text, we only need a tiny array of runs (no malloc()) */
 289     Run simpleRuns[1];
 290
 291     /* for inverse Bidi with insertion of directional marks */
 292     InsertPoints insertPoints;
 293
 294     /* for option UBIDI_OPTION_REMOVE_CONTROLS */
 295     int32_t controlCount;
 296
 297     /* for Bidi class callback */
 298     UBiDiClassCallback *fnClassCallback;    /* action pointer */
 299     const void *coClassCallback;            /* context pointer */
 300 };
 301
 302 #define IS_VALID_PARA(x) ((x) && ((x)->pParaBiDi==(x)))
 303 #define IS_VALID_PARA_OR_LINE(x) ((x) && ((x)->pParaBiDi==(x) || (((x)->pParaBiDi) && (x)->pParaBiDi->pParaBiDi==(x)->pParaBiDi)))
 304
 305 typedef union {
 306     DirProp *dirPropsMemory;
 307     UBiDiLevel *levelsMemory;
 308     Para *parasMemory;
 309     Run *runsMemory;
 310 } BidiMemoryForAllocation;
 311
 312 /* Macros for initial checks at function entry */
 313 #define RETURN_IF_NULL_OR_FAILING_ERRCODE(pErrcode, retvalue)   \
 314         if((pErrcode)==NULL || U_FAILURE(*pErrcode)) return retvalue
 315 #define RETURN_IF_NOT_VALID_PARA(bidi, errcode, retvalue)   \
 316         if(!IS_VALID_PARA(bidi)) {  \
 317             errcode=U_INVALID_STATE_ERROR;  \
 318             return retvalue;                \
 319         }
 320 #define RETURN_IF_NOT_VALID_PARA_OR_LINE(bidi, errcode, retvalue)   \
 321         if(!IS_VALID_PARA_OR_LINE(bidi)) {  \
 322             errcode=U_INVALID_STATE_ERROR;  \
 323             return retvalue;                \
 324         }
 325 #define RETURN_IF_BAD_RANGE(arg, start, limit, errcode, retvalue)   \
 326         if((arg)<(start) || (arg)>=(limit)) {       \
 327             (errcode)=U_ILLEGAL_ARGUMENT_ERROR;     \
 328             return retvalue;                        \
 329         }
 330
 331 #define RETURN_VOID_IF_NULL_OR_FAILING_ERRCODE(pErrcode)   \
 332         if((pErrcode)==NULL || U_FAILURE(*pErrcode)) return
 333 #define RETURN_VOID_IF_NOT_VALID_PARA(bidi, errcode)   \
 334         if(!IS_VALID_PARA(bidi)) {  \
 335             errcode=U_INVALID_STATE_ERROR;  \
 336             return;                \
 337         }
 338 #define RETURN_VOID_IF_NOT_VALID_PARA_OR_LINE(bidi, errcode)   \
 339         if(!IS_VALID_PARA_OR_LINE(bidi)) {  \
 340             errcode=U_INVALID_STATE_ERROR;  \
 341             return;                \
 342         }
 343 #define RETURN_VOID_IF_BAD_RANGE(arg, start, limit, errcode)   \
 344         if((arg)<(start) || (arg)>=(limit)) {       \
 345             (errcode)=U_ILLEGAL_ARGUMENT_ERROR;     \
 346             return;                        \
 347         }
 348
 349 /* helper function to (re)allocate memory if allowed */
 350 U_CFUNC UBool
 351 ubidi_getMemory(BidiMemoryForAllocation *pMemory, int32_t *pSize, UBool mayAllocate, int32_t sizeNeeded);
 352
 353 /* helper macros for each allocated array in UBiDi */
 354 #define getDirPropsMemory(pBiDi, length) \
 355         ubidi_getMemory((BidiMemoryForAllocation *)&(pBiDi)->dirPropsMemory, &(pBiDi)->dirPropsSize, \
 356                         (pBiDi)->mayAllocateText, (length))
 357
 358 #define getLevelsMemory(pBiDi, length) \
 359         ubidi_getMemory((BidiMemoryForAllocation *)&(pBiDi)->levelsMemory, &(pBiDi)->levelsSize, \
 360                         (pBiDi)->mayAllocateText, (length))
 361
 362 #define getRunsMemory(pBiDi, length) \
 363         ubidi_getMemory((BidiMemoryForAllocation *)&(pBiDi)->runsMemory, &(pBiDi)->runsSize, \
 364                         (pBiDi)->mayAllocateRuns, (length)*sizeof(Run))
 365
 366 /* additional macros used by ubidi_open() - always allow allocation */
 367 #define getInitialDirPropsMemory(pBiDi, length) \
 368         ubidi_getMemory((BidiMemoryForAllocation *)&(pBiDi)->dirPropsMemory, &(pBiDi)->dirPropsSize, \
 369                         TRUE, (length))
 370
 371 #define getInitialLevelsMemory(pBiDi, length) \
 372         ubidi_getMemory((BidiMemoryForAllocation *)&(pBiDi)->levelsMemory, &(pBiDi)->levelsSize, \
 373                         TRUE, (length))
 374
 375 #define getInitialParasMemory(pBiDi, length) \
 376         ubidi_getMemory((BidiMemoryForAllocation *)&(pBiDi)->parasMemory, &(pBiDi)->parasSize, \
 377                         TRUE, (length)*sizeof(Para))
 378
 379 #define getInitialRunsMemory(pBiDi, length) \
 380         ubidi_getMemory((BidiMemoryForAllocation *)&(pBiDi)->runsMemory, &(pBiDi)->runsSize, \
 381                         TRUE, (length)*sizeof(Run))
 382
 383 #endif
 384
 385 #endif