kc3-lang/gnulib/lib/unilbrk/u32-possible-linebreaks.c

• Show log

  Commit

• Hash : b2e2010c
  Author :
  Date : 2010-01-01T10:31:12
  

  update nearly all FSF copyright year lists to include 2010
  
  Use the same procedure as for 2009, outlined in
  http://thread.gmane.org/gmane.comp.lib.gnulib.bugs/20081
  

Download

• lib/unilbrk/u32-possible-linebreaks.c

• /* Line breaking of UTF-32 strings.
     Copyright (C) 2001-2003, 2006-2010 Free Software Foundation, Inc.
     Written by Bruno Haible <bruno@clisp.org>, 2001.
  
     This program is free software: you can redistribute it and/or modify it
     under the terms of the GNU Lesser General Public License as published
     by the Free Software Foundation; either version 3 of the License, or
     (at your option) any later version.
  
     This program is distributed in the hope that it will be useful,
     but WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     Lesser General Public License for more details.
  
     You should have received a copy of the GNU Lesser General Public License
     along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  
  #include <config.h>
  
  /* Specification.  */
  #include "unilbrk.h"
  
  #include <stdlib.h>
  
  #include "unilbrk/lbrktables.h"
  #include "uniwidth/cjk.h"
  
  void
  u32_possible_linebreaks (const uint32_t *s, size_t n, const char *encoding, char *p)
  {
    int LBP_AI_REPLACEMENT = (is_cjk_encoding (encoding) ? LBP_ID : LBP_AL);
    const uint32_t *s_end = s + n;
    int last_prop = LBP_BK; /* line break property of last non-space character */
    char *seen_space = NULL; /* Was a space seen after the last non-space character? */
    char *seen_space2 = NULL; /* At least two spaces after the last non-space? */
  
    while (s < s_end)
      {
        ucs4_t uc = *s;
        int prop = unilbrkprop_lookup (uc);
  
        if (prop == LBP_BK)
          {
            /* Mandatory break.  */
            *p = UC_BREAK_MANDATORY;
            last_prop = LBP_BK;
            seen_space = NULL;
            seen_space2 = NULL;
          }
        else
          {
            char *q;
  
            /* Resolve property values whose behaviour is not fixed.  */
            switch (prop)
              {
              case LBP_AI:
                /* Resolve ambiguous.  */
                prop = LBP_AI_REPLACEMENT;
                break;
              case LBP_CB:
                /* This is arbitrary.  */
                prop = LBP_ID;
                break;
              case LBP_SA:
                /* We don't handle complex scripts yet.
                   Treat LBP_SA like LBP_XX.  */
              case LBP_XX:
                /* This is arbitrary.  */
                prop = LBP_AL;
                break;
              }
  
            /* Deal with spaces and combining characters.  */
            q = p;
            if (prop == LBP_SP)
              {
                /* Don't break just before a space.  */
                *p = UC_BREAK_PROHIBITED;
                seen_space2 = seen_space;
                seen_space = p;
              }
            else if (prop == LBP_ZW)
              {
                /* Don't break just before a zero-width space.  */
                *p = UC_BREAK_PROHIBITED;
                last_prop = LBP_ZW;
                seen_space = NULL;
                seen_space2 = NULL;
              }
            else if (prop == LBP_CM)
              {
                /* Don't break just before a combining character, except immediately after a
                   zero-width space.  */
                if (last_prop == LBP_ZW)
                  {
                    /* Break after zero-width space.  */
                    *p = UC_BREAK_POSSIBLE;
                    /* A combining character turns a preceding space into LBP_ID.  */
                    last_prop = LBP_ID;
                  }
                else
                  {
                    *p = UC_BREAK_PROHIBITED;
                    /* A combining character turns a preceding space into LBP_ID.  */
                    if (seen_space != NULL)
                      {
                        q = seen_space;
                        seen_space = seen_space2;
                        prop = LBP_ID;
                        goto lookup_via_table;
                      }
                  }
              }
            else
              {
               lookup_via_table:
                /* prop must be usable as an index for table 7.3 of UTR #14.  */
                if (!(prop >= 0 && prop < sizeof (unilbrk_table) / sizeof (unilbrk_table[0])))
                  abort ();
  
                if (last_prop == LBP_BK)
                  {
                    /* Don't break at the beginning of a line.  */
                    *q = UC_BREAK_PROHIBITED;
                  }
                else if (last_prop == LBP_ZW)
                  {
                    /* Break after zero-width space.  */
                    *q = UC_BREAK_POSSIBLE;
                  }
                else
                  {
                    switch (unilbrk_table [last_prop] [prop])
                      {
                      case D:
                        *q = UC_BREAK_POSSIBLE;
                        break;
                      case I:
                        *q = (seen_space != NULL ? UC_BREAK_POSSIBLE : UC_BREAK_PROHIBITED);
                        break;
                      case P:
                        *q = UC_BREAK_PROHIBITED;
                        break;
                      default:
                        abort ();
                      }
                  }
                last_prop = prop;
                seen_space = NULL;
                seen_space2 = NULL;
              }
          }
  
        s++;
        p++;
      }
  }
  

Download