usr/src/lib/libast/common/tm/tmxduration.c

   1 /***********************************************************************
   2 *                                                                      *
   3 *               This software is part of the ast package               *
   4 *          Copyright (c) 1985-2010 AT&T Intellectual Property          *
   5 *                      and is licensed under the                       *
   6 *                  Common Public License, Version 1.0                  *
   7 *                    by AT&T Intellectual Property                     *
   8 *                                                                      *
   9 *                A copy of the License is available at                 *
  10 *            http://www.opensource.org/licenses/cpl1.0.txt             *
  11 *         (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9)         *
  12 *                                                                      *
  13 *              Information and Software Systems Research               *
  14 *                            AT&T Research                             *
  15 *                           Florham Park NJ                            *
  16 *                                                                      *
  17 *                 Glenn Fowler <gsf@research.att.com>                  *
  18 *                  David Korn <dgk@research.att.com>                   *
  19 *                   Phong Vo <kpv@research.att.com>                    *
  20 *                                                                      *
  21 ***********************************************************************/
  22 #pragma prototyped
  23
  24 #include <tmx.h>
  25 #include <ctype.h>
  26
  27 /*
  28  * parse duration expression in s and return Time_t value
  29  * if non-null, e points to the first unused char in s
  30  * returns 0 with *e==s on error
  31  */
  32
  33 Time_t
  34 tmxduration(const char* s, char** e)
  35 {
  36         Time_t          ns;
  37         Time_t          ts;
  38         Time_t          now;
  39         char*           last;
  40         char*           t;
  41         char*           x;
  42         Sfio_t*         f;
  43         int             i;
  44
  45         now = TMX_NOW;
  46         while (isspace(*s))
  47                 s++;
  48         if (*s == 'P' || *s == 'p')
  49                 ns = tmxdate(s, &last, now) - now;
  50         else
  51         {
  52                 ns = strtod(s, &last) * TMX_RESOLUTION;
  53                 if (*last && (f = sfstropen()))
  54                 {
  55                         sfprintf(f, "exact %s", s);
  56                         t = sfstruse(f);
  57                         ts = tmxdate(t, &x, now);
  58                         if ((i = x - t - 6) > (last - s))
  59                         {
  60                                 last = (char*)s + i;
  61                                 ns = ts - now;
  62                         }
  63                         else
  64                         {
  65                                 sfprintf(f, "p%s", s);
  66                                 t = sfstruse(f);
  67                                 ts = tmxdate(t, &x, now);
  68                                 if ((i = x - t - 1) > (last - s))
  69                                 {
  70                                         last = (char*)s + i;
  71                                         ns = ts - now;
  72                                 }
  73                         }
  74                         sfstrclose(f);
  75                 }
  76         }
  77         if (e)
  78                 *e = last;
  79         return ns;
  80 }