locale/weightwc.h

   1 /* Copyright (C) 1996, 1997, 1998, 1999 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Written by Ulrich Drepper, <drepper@cygnus.com>.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Library General Public License as
   7    published by the Free Software Foundation; either version 2 of the
   8    License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Library General Public License for more details.
  14
  15    You should have received a copy of the GNU Library General Public
  16    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  17    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  18    Boston, MA 02111-1307, USA.  */
  19
  20 /* Find index of weight.  */
  21 static inline int32_t
  22 findidx (const wint_t **cpp)
  23 {
  24   int_fast32_t i;
  25   const wint_t *cp;
  26   wint_t ch;
  27   size_t idx;
  28   size_t cnt = 0;
  29
  30   ch = *(*cpp)++;
  31   idx = ch % size;
  32   while (names[idx] != ch)
  33     {
  34       if (++cnt == layers)
  35         /* We didn't find the name.  It is case for UNDEFINED.  */
  36         return 0;
  37       idx += size;
  38     }
  39   i = table[idx];
  40
  41   if (i >= 0)
  42     /* This is an index into the weight table.  Cool.  */
  43     return i;
  44
  45   /* Oh well, more than one sequence starting with this byte.
  46      Search for the correct one.  */
  47   cp = &extra[-i];
  48   while (1)
  49     {
  50       size_t nhere;
  51       const wint_t *usrc = *cpp;
  52
  53       /* The first thing is the index.  */
  54       i = *((int32_t *) cp);
  55       cp += sizeof (int32_t);
  56
  57       /* Next is the length of the byte sequence.  These are always
  58          short byte sequences so there is no reason to call any
  59          function (even if they are inlined).  */
  60       nhere = *cp++;
  61
  62       if (i >= 0)
  63         {
  64           /* It is a single character.  If it matches we found our
  65              index.  Note that at the end of each list there is an
  66              entry of length zero which represents the single byte
  67              sequence.  The first (and here only) byte was tested
  68              already.  */
  69           size_t cnt;
  70
  71           for (cnt = 0; cnt < nhere; ++cnt)
  72             if (cp[cnt] != usrc[cnt])
  73               break;
  74
  75           if (cnt == nhere)
  76             {
  77               /* Found it.  */
  78               *cpp += nhere;
  79               return i;
  80             }
  81
  82           /* Up to the next entry.  */
  83           cp += nhere;
  84         }
  85       else
  86         {
  87           /* This is a range of characters.  First decide whether the
  88              current byte sequence lies in the range.  */
  89           size_t cnt;
  90           size_t offset = 0;
  91
  92           for (cnt = 0; cnt < nhere; ++cnt)
  93             if (cp[cnt] != usrc[cnt])
  94               break;
  95
  96           if (cnt != nhere)
  97             {
  98               if (cp[cnt] > usrc[cnt])
  99                 {
 100                   /* Cannot be in this range.  */
 101                   cp += 2 * nhere;
 102                   continue;
 103                 }
 104
 105               /* Test against the end of the range.  */
 106               for (cnt = 0; cnt < nhere; ++cnt)
 107                 if (cp[nhere + cnt] != usrc[cnt])
 108                   break;
 109
 110               if (cnt != nhere && cp[nhere + cnt] < usrc[cnt])
 111                 {
 112                   /* Cannot be in this range.  */
 113                   cp += 2 * nhere;
 114                   continue;
 115                 }
 116
 117               /* This range matches the next characters.  Now find
 118                  the offset in the indirect table.  */
 119               for (cnt = 0; cp[cnt] == usrc[cnt]; ++cnt);
 120
 121               do
 122                 {
 123                   offset <<= 8;
 124                   offset += usrc[cnt] - cp[cnt];
 125                 }
 126               while (++cnt < nhere);
 127             }
 128
 129           *cpp += nhere;
 130           return offset;
 131         }
 132     }
 133
 134   /* NOTREACHED */
 135   return 0x43219876;
 136 }