resolv/ns_ttl.c

   1 /*
   2  * Copyright (c) 1996,1999 by Internet Software Consortium.
   3  *
   4  * Permission to use, copy, modify, and distribute this software for any
   5  * purpose with or without fee is hereby granted, provided that the above
   6  * copyright notice and this permission notice appear in all copies.
   7  *
   8  * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
   9  * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
  10  * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
  11  * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
  12  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
  13  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
  14  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
  15  * SOFTWARE.
  16  */
  17
  18 #ifndef lint
  19 static const char rcsid[] = "$Id$";
  20 #endif
  21
  22 /* Import. */
  23 #include <arpa/nameser.h>
  24
  25 #include <ctype.h>
  26 #include <errno.h>
  27 #include <stdio.h>
  28 #include <string.h>
  29
  30 #ifdef SPRINTF_CHAR
  31 # define SPRINTF(x) strlen(sprintf/**/x)
  32 #else
  33 # define SPRINTF(x) ((size_t)sprintf x)
  34 #endif
  35
  36 /* Forward. */
  37
  38 static int      fmt1(int t, char s, char **buf, size_t *buflen);
  39
  40 /* Macros. */
  41
  42 #define T(x) if ((x) < 0) return (-1); else (void)NULL
  43
  44 /* Public. */
  45
  46 int
  47 ns_format_ttl(u_long src, char *dst, size_t dstlen) {
  48         char *odst = dst;
  49         int secs, mins, hours, days, weeks, x;
  50         char *p;
  51
  52         secs = src % 60;   src /= 60;
  53         mins = src % 60;   src /= 60;
  54         hours = src % 24;  src /= 24;
  55         days = src % 7;    src /= 7;
  56         weeks = src;       src = 0;
  57
  58         x = 0;
  59         if (weeks) {
  60                 T(fmt1(weeks, 'W', &dst, &dstlen));
  61                 x++;
  62         }
  63         if (days) {
  64                 T(fmt1(days, 'D', &dst, &dstlen));
  65                 x++;
  66         }
  67         if (hours) {
  68                 T(fmt1(hours, 'H', &dst, &dstlen));
  69                 x++;
  70         }
  71         if (mins) {
  72                 T(fmt1(mins, 'M', &dst, &dstlen));
  73                 x++;
  74         }
  75         if (secs || !(weeks || days || hours || mins)) {
  76                 T(fmt1(secs, 'S', &dst, &dstlen));
  77                 x++;
  78         }
  79
  80         if (x > 1) {
  81                 int ch;
  82
  83                 for (p = odst; (ch = *p) != '\0'; p++)
  84                         if (isascii(ch) && isupper(ch))
  85                                 *p = tolower(ch);
  86         }
  87
  88         return (dst - odst);
  89 }
  90
  91 int
  92 ns_parse_ttl(const char *src, u_long *dst) {
  93         u_long ttl, tmp;
  94         int ch, digits, dirty;
  95
  96         ttl = 0;
  97         tmp = 0;
  98         digits = 0;
  99         dirty = 0;
 100         while ((ch = *src++) != '\0') {
 101                 if (!isascii(ch) || !isprint(ch))
 102                         goto einval;
 103                 if (isdigit(ch)) {
 104                         tmp *= 10;
 105                         tmp += (ch - '0');
 106                         digits++;
 107                         continue;
 108                 }
 109                 if (digits == 0)
 110                         goto einval;
 111                 if (islower(ch))
 112                         ch = toupper(ch);
 113                 switch (ch) {
 114                 case 'W':  tmp *= 7;
 115                 case 'D':  tmp *= 24;
 116                 case 'H':  tmp *= 60;
 117                 case 'M':  tmp *= 60;
 118                 case 'S':  break;
 119                 default:   goto einval;
 120                 }
 121                 ttl += tmp;
 122                 tmp = 0;
 123                 digits = 0;
 124                 dirty = 1;
 125         }
 126         if (digits > 0) {
 127                 if (dirty)
 128                         goto einval;
 129                 else
 130                         ttl += tmp;
 131         }
 132         *dst = ttl;
 133         return (0);
 134
 135  einval:
 136         __set_errno (EINVAL);
 137         return (-1);
 138 }
 139
 140 /* Private. */
 141
 142 static int
 143 fmt1(int t, char s, char **buf, size_t *buflen) {
 144         char tmp[50];
 145         size_t len;
 146
 147         len = SPRINTF((tmp, "%d%c", t, s));
 148         if (len + 1 > *buflen)
 149                 return (-1);
 150         strcpy(*buf, tmp);
 151         *buf += len;
 152         *buflen -= len;
 153         return (0);
 154 }