usr/src/lib/libast/common/tm/tmpoff.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  * Glenn Fowler
  25  * AT&T Bell Laboratories
  26  *
  27  * time conversion support
  28  */
  29
  30 #include <ast.h>
  31 #include <tm.h>
  32
  33 /*
  34  * n is minutes west of UTC
  35  *
  36  * append p and SHHMM part of n to s
  37  * where S is + or -
  38  *
  39  * n ignored if n==d
  40  * end of s is returned
  41  */
  42
  43 char*
  44 tmpoff(register char* s, size_t z, register const char* p, register int n, int d)
  45 {
  46         register char*  e = s + z;
  47
  48         while (s < e && (*s = *p++))
  49                 s++;
  50         if (n != d && s < e)
  51         {
  52                 if (n < 0)
  53                 {
  54                         n = -n;
  55                         *s++ = '+';
  56                 }
  57                 else
  58                         *s++ = '-';
  59                 s += sfsprintf(s, e - s, "%02d%02d", n / 60, n % 60);
  60         }
  61         return s;
  62 }