libjava/java/text/natCollator.cc

   1 // natCollator.cc - Native code for collation.
   2
   3 /* Copyright (C) 1999  Free Software Foundation
   4
   5    This file is part of libgcj.
   6
   7 This software is copyrighted work licensed under the terms of the
   8 Libgcj License.  Please consult the file "LIBGCJ_LICENSE" for
   9 details.  */
  10
  11 // Written by Tom Tromey <tromey@cygnus.com>.
  12
  13 #include <config.h>
  14
  15 #include <gcj/cni.h>
  16 #include <jvm.h>
  17
  18 #include <java/text/Collator.h>
  19 #include <java/lang/StringBuffer.h>
  20
  21 #include <java-chardecomp.h>
  22
  23 void
  24 java::text::Collator::decomposeCharacter (jchar c,
  25                                           java::lang::StringBuffer *buf)
  26 {
  27   if (decmp == NO_DECOMPOSITION)
  28     {
  29       buf->append(c);
  30       return;
  31     }
  32
  33   const struct decomp_entry *base;
  34   int high;
  35
  36   if (decmp == FULL_DECOMPOSITION)
  37     {
  38       base = full_decomposition;
  39       high = sizeof (full_decomposition) / sizeof (struct decomp_entry);
  40     }
  41   else
  42     {
  43       base = canonical_decomposition;
  44       high = sizeof (canonical_decomposition) / sizeof (struct decomp_entry);
  45     }
  46
  47   // FIXME: this is probably a bit slow for the task at hand.
  48   int i = high / 2;
  49   int low = 0;
  50   while (true)
  51     {
  52       if (c < base[i].key)
  53         high = i;
  54       else if (c > base[i].key)
  55         low = i;
  56       else
  57         break;
  58
  59       int old = i;
  60       i = (high + low) / 2;
  61       if (i == old)
  62         {
  63           // Not in table, so it expands to itself.
  64           buf->append(c);
  65           return;
  66         }
  67     }
  68
  69   for (int j = 0; base[i].value[j] != '\0'; j += 2)
  70     {
  71       jchar x = (base[i].value[j] << 8) | (base[i].value[j + 1]);
  72       buf->append (x);
  73     }
  74 }