diplodocus.org Git - nmh/blob - sbr/uprf.c

   1
   2 /*
   3  * uprf.c -- "unsigned" lexical prefix
   4  *
   5  * This code is Copyright (c) 2002, by the authors of nmh.  See the
   6  * COPYRIGHT file in the root directory of the nmh distribution for
   7  * complete copyright information.
   8  */
   9
  10 #include <h/mh.h>
  11
  12 #define TO_LOWER 040
  13 #define NO_MASK  000
  14
  15
  16 int
  17 uprf (char *c1, char *c2)
  18 {
  19     int c, mask;
  20
  21     if (!(c1 && c2))
  22         return 0;
  23
  24     while ((c = *c2++))
  25     {
  26 #ifdef LOCALE
  27         c &= 0xff;
  28         mask = *c1 & 0xff;
  29         c = (isalpha(c) && isupper(c)) ? tolower(c) : c;
  30         mask = (isalpha(mask) && isupper(mask)) ? tolower(mask) : mask;
  31         if (c != mask)
  32 #else
  33         mask = (isalpha(c) && isalpha(*c1)) ?  TO_LOWER : NO_MASK;
  34         if ((c | mask) != (*c1 | mask))
  35 #endif
  36             return 0;
  37         else
  38             c1++;
  39     }
  40     return 1;
  41 }