resolv/ns_ttl.c

   1 /*
   2  * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
   3  * Copyright (c) 1996,1999 by Internet Software Consortium.
   4  *
   5  * Permission to use, copy, modify, and distribute this software for any
   6  * purpose with or without fee is hereby granted, provided that the above
   7  * copyright notice and this permission notice appear in all copies.
   8  *
   9  * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
  10  * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
  11  * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
  12  * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
  13  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
  14  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
  15  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
  16  * SOFTWARE.
  17  */
  18
  19 #if !defined(_LIBC) && !defined(lint)
  20 static const char rcsid[] = "$BINDId: ns_ttl.c,v 8.8 1999/10/13 16:39:36 vixie Exp $";
  21 #endif
  22
  23 /* Import. */
  24
  25 #include <arpa/nameser.h>
  26
  27 #include <ctype.h>
  28 #include <errno.h>
  29 #include <stdio.h>
  30 #include <string.h>
  31
  32 #ifdef SPRINTF_CHAR
  33 # define SPRINTF(x) strlen(sprintf/**/x)
  34 #else
  35 # define SPRINTF(x) ((size_t)sprintf x)
  36 #endif
  37
  38 /* Forward. */
  39
  40 static int      fmt1(int t, char s, char **buf, size_t *buflen);
  41
  42 /* Macros. */
  43
  44 #define T(x) if ((x) < 0) return (-1); else (void)NULL
  45
  46 /* Public. */
  47
  48 int
  49 ns_format_ttl(u_long src, char *dst, size_t dstlen) {
  50         char *odst = dst;
  51         int secs, mins, hours, days, weeks, x;
  52         char *p;
  53
  54         secs = src % 60;   src /= 60;
  55         mins = src % 60;   src /= 60;
  56         hours = src % 24;  src /= 24;
  57         days = src % 7;    src /= 7;
  58         weeks = src;       src = 0;
  59
  60         x = 0;
  61         if (weeks) {
  62                 T(fmt1(weeks, 'W', &dst, &dstlen));
  63                 x++;
  64         }
  65         if (days) {
  66                 T(fmt1(days, 'D', &dst, &dstlen));
  67                 x++;
  68         }
  69         if (hours) {
  70                 T(fmt1(hours, 'H', &dst, &dstlen));
  71                 x++;
  72         }
  73         if (mins) {
  74                 T(fmt1(mins, 'M', &dst, &dstlen));
  75                 x++;
  76         }
  77         if (secs || !(weeks || days || hours || mins)) {
  78                 T(fmt1(secs, 'S', &dst, &dstlen));
  79                 x++;
  80         }
  81
  82         if (x > 1) {
  83                 int ch;
  84
  85                 for (p = odst; (ch = *p) != '\0'; p++)
  86                         if (isascii(ch) && isupper(ch))
  87                                 *p = tolower(ch);
  88         }
  89
  90         return (dst - odst);
  91 }
  92 libresolv_hidden_def (ns_format_ttl)
  93
  94 // Seems not to be needed.  It's not exported from the DSO.  Some libresolv.a
  95 // might depend on it so we let it in.
  96 int
  97 ns_parse_ttl(const char *src, u_long *dst) {
  98         u_long ttl, tmp;
  99         int ch, digits, dirty;
 100
 101         ttl = 0;
 102         tmp = 0;
 103         digits = 0;
 104         dirty = 0;
 105         while ((ch = *src++) != '\0') {
 106                 if (!isascii(ch) || !isprint(ch))
 107                         goto einval;
 108                 if (isdigit(ch)) {
 109                         tmp *= 10;
 110                         tmp += (ch - '0');
 111                         digits++;
 112                         continue;
 113                 }
 114                 if (digits == 0)
 115                         goto einval;
 116                 if (islower(ch))
 117                         ch = toupper(ch);
 118                 switch (ch) {
 119                 case 'W':  tmp *= 7;
 120                 case 'D':  tmp *= 24;
 121                 case 'H':  tmp *= 60;
 122                 case 'M':  tmp *= 60;
 123                 case 'S':  break;
 124                 default:   goto einval;
 125                 }
 126                 ttl += tmp;
 127                 tmp = 0;
 128                 digits = 0;
 129                 dirty = 1;
 130         }
 131         if (digits > 0) {
 132                 if (dirty)
 133                         goto einval;
 134                 else
 135                         ttl += tmp;
 136         } else if (!dirty)
 137                 goto einval;
 138         *dst = ttl;
 139         return (0);
 140
 141  einval:
 142         __set_errno (EINVAL);
 143         return (-1);
 144 }
 145
 146 /* Private. */
 147
 148 static int
 149 fmt1(int t, char s, char **buf, size_t *buflen) {
 150         char tmp[50];
 151         size_t len;
 152
 153         len = SPRINTF((tmp, "%d%c", t, s));
 154         if (len + 1 > *buflen)
 155                 return (-1);
 156         strcpy(*buf, tmp);
 157         *buf += len;
 158         *buflen -= len;
 159         return (0);
 160 }
 161
 162 /*! \file */