timezone/scheck.c

   1 /*
   2 ** This file is in the public domain, so clarified as of
   3 ** 2006-07-17 by Arthur David Olson.
   4 */
   5
   6 /*LINTLIBRARY*/
   7
   8 #include "private.h"
   9
  10 const char *
  11 scheck(const char *const string, const char *const format)
  12 {
  13         register char *         fbuf;
  14         register const char *   fp;
  15         register char *         tp;
  16         register int            c;
  17         register const char *   result;
  18         char                    dummy;
  19
  20         result = "";
  21         if (string == NULL || format == NULL)
  22                 return result;
  23         fbuf = malloc(2 * strlen(format) + 4);
  24         if (fbuf == NULL)
  25                 return result;
  26         fp = format;
  27         tp = fbuf;
  28         while ((*tp++ = c = *fp++) != '\0') {
  29                 if (c != '%')
  30                         continue;
  31                 if (*fp == '%') {
  32                         *tp++ = *fp++;
  33                         continue;
  34                 }
  35                 *tp++ = '*';
  36                 if (*fp == '*')
  37                         ++fp;
  38                 while (is_digit(*fp))
  39                         *tp++ = *fp++;
  40                 if (*fp == 'l' || *fp == 'h')
  41                         *tp++ = *fp++;
  42                 else if (*fp == '[')
  43                         do *tp++ = *fp++;
  44                                 while (*fp != '\0' && *fp != ']');
  45                 if ((*tp++ = *fp++) == '\0')
  46                         break;
  47         }
  48         *(tp - 1) = '%';
  49         *tp++ = 'c';
  50         *tp = '\0';
  51         if (sscanf(string, fbuf, &dummy) != 1)
  52                 result = format;
  53         free(fbuf);
  54         return result;
  55 }