maint/gnulib/lib/unigbrk.in.h

/* */
   1 /* Grapheme cluster breaks in Unicode strings.
   2    Copyright (C) 2010-2021 Free Software Foundation, Inc.
   3    Written by Ben Pfaff <blp@cs.stanford.edu>, 2010.
   4 
   5    This file is free software.
   6    It is dual-licensed under "the GNU LGPLv3+ or the GNU GPLv2+".
   7    You can redistribute it and/or modify it under either
   8      - the terms of the GNU Lesser General Public License as published
   9        by the Free Software Foundation; either version 3, or (at your
  10        option) any later version, or
  11      - the terms of the GNU General Public License as published by the
  12        Free Software Foundation; either version 2, or (at your option)
  13        any later version, or
  14      - the same dual license "the GNU LGPLv3+ or the GNU GPLv2+".
  15 
  16    This file is distributed in the hope that it will be useful,
  17    but WITHOUT ANY WARRANTY; without even the implied warranty of
  18    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  19    Lesser General Public License and the GNU General Public License
  20    for more details.
  21 
  22    You should have received a copy of the GNU Lesser General Public
  23    License and of the GNU General Public License along with this
  24    program.  If not, see <https://www.gnu.org/licenses/>.  */
  25 
  26 #ifndef _UNIGBRK_H
  27 #define _UNIGBRK_H
  28 
  29 /* Get bool.  */
  30 #include <stdbool.h>
  31 
  32 /* Get size_t. */
  33 #include <stddef.h>
  34 
  35 #include "unitypes.h"
  36 
  37 #ifdef __cplusplus
  38 extern "C" {
  39 #endif
  40 
  41 /* ========================================================================= */
  42 
  43 /* Property defined in Unicode Standard Annex #29, section "Grapheme Cluster
  44    Boundaries"
  45    <https://unicode.org/reports/tr29/#Grapheme_Cluster_Boundaries> */
  46 
  47 /* Possible values of the Grapheme_Cluster_Break property.
  48    This enumeration may be extended in the future.  */
  49 enum
  50 {
  51   GBP_OTHER        = 0,
  52   GBP_CR           = 1,
  53   GBP_LF           = 2,
  54   GBP_CONTROL      = 3,
  55   GBP_EXTEND       = 4,
  56   GBP_PREPEND      = 5,
  57   GBP_SPACINGMARK  = 6,
  58   GBP_L            = 7,
  59   GBP_V            = 8,
  60   GBP_T            = 9,
  61   GBP_LV           = 10,
  62   GBP_LVT          = 11,
  63   GBP_RI           = 12,
  64   GBP_ZWJ          = 13,
  65   GBP_EB           = 14,
  66   GBP_EM           = 15,
  67   GBP_GAZ          = 16,
  68   GBP_EBG          = 17
  69 };
  70 
  71 /* Return the Grapheme_Cluster_Break property of a Unicode character. */
  72 extern int
  73        uc_graphemeclusterbreak_property (ucs4_t uc)
  74        _UC_ATTRIBUTE_CONST;
  75 
  76 /* ========================================================================= */
  77 
  78 /* Grapheme cluster breaks.  */
  79 
  80 /* Returns true if there is a grapheme cluster boundary between Unicode code
  81    points A and B.  A "grapheme cluster" is an approximation to a
  82    user-perceived character, which sometimes corresponds to multiple code
  83    points.  For example, an English letter followed by an acute accent can be
  84    expressed as two consecutive Unicode code points, but it is perceived by the
  85    user as only a single character and therefore constitutes a single grapheme
  86    cluster.
  87 
  88    Implements extended (not legacy) grapheme cluster rules, because UAX #29
  89    indicates that they are preferred.
  90 
  91    Use A == 0 or B == 0 to indicate start of text or end of text,
  92    respectively. */
  93 extern bool
  94        uc_is_grapheme_break (ucs4_t a, ucs4_t b)
  95        _UC_ATTRIBUTE_CONST;
  96 
  97 /* Returns the start of the next grapheme cluster following S, or NULL if the
  98    end of the string has been reached. */
  99 extern const uint8_t *
 100        u8_grapheme_next (const uint8_t *s, const uint8_t *end)
 101        _UC_ATTRIBUTE_PURE;
 102 extern const uint16_t *
 103        u16_grapheme_next (const uint16_t *s, const uint16_t *end)
 104        _UC_ATTRIBUTE_PURE;
 105 extern const uint32_t *
 106        u32_grapheme_next (const uint32_t *s, const uint32_t *end)
 107        _UC_ATTRIBUTE_PURE;
 108 
 109 /* Returns the start of the previous grapheme cluster before S, or NULL if the
 110    start of the string has been reached. */
 111 extern const uint8_t *
 112        u8_grapheme_prev (const uint8_t *s, const uint8_t *start)
 113        _UC_ATTRIBUTE_PURE;
 114 extern const uint16_t *
 115        u16_grapheme_prev (const uint16_t *s, const uint16_t *start)
 116        _UC_ATTRIBUTE_PURE;
 117 extern const uint32_t *
 118        u32_grapheme_prev (const uint32_t *s, const uint32_t *start)
 119        _UC_ATTRIBUTE_PURE;
 120 
 121 /* Determine the grapheme cluster boundaries in S, and store the result at
 122    p[0..n-1].  p[i] = 1 means that a new grapheme cluster begins at s[i].  p[i]
 123    = 0 means that s[i-1] and s[i] are part of the same grapheme cluster.  p[0]
 124    will always be 1.
 125  */
 126 extern void
 127        u8_grapheme_breaks (const uint8_t *s, size_t n, char *p);
 128 extern void
 129        u16_grapheme_breaks (const uint16_t *s, size_t n, char *p);
 130 extern void
 131        u32_grapheme_breaks (const uint32_t *s, size_t n, char *p);
 132 extern void
 133        ulc_grapheme_breaks (const char *s, size_t n, char *p);
 134 extern void
 135        uc_grapheme_breaks (const ucs4_t *s, size_t n, char *p);
 136 
 137 /* ========================================================================= */
 138 
 139 #ifdef __cplusplus
 140 }
 141 #endif
 142 
 143 
 144 #endif /* _UNIGBRK_H */
/* */
root/maint/gnulib/lib/unigbrk.in.h
