usr/src/lib/libresolv2/common/nameser/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 ISC DISCLAIMS ALL WARRANTIES
  10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  11  * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
  12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
  15  * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  16  */
  17
  18 #include "port_before.h"
  19
  20 #include <arpa/nameser.h>
  21
  22 #include <ctype.h>
  23 #include <errno.h>
  24 #include <stdio.h>
  25 #include <string.h>
  26
  27 #include "port_after.h"
  28
  29 #ifdef SPRINTF_CHAR
  30 # define SPRINTF(x) strlen(sprintf/**/x)
  31 #else
  32 # define SPRINTF(x) ((size_t)sprintf x)
  33 #endif
  34
  35 /* Forward. */
  36
  37 static int      fmt1(int t, char s, char **buf, size_t *buflen);
  38
  39 /* Macros. */
  40
  41 #define T(x) if ((x) < 0) return (-1); else (void)NULL
  42
  43 /* Public. */
  44
  45 int
  46 ns_format_ttl(u_long src, char *dst, size_t dstlen) {
  47         char *odst = dst;
  48         int secs, mins, hours, days, weeks, x;
  49         char *p;
  50
  51         secs = src % 60;   src /= 60;
  52         mins = src % 60;   src /= 60;
  53         hours = src % 24;  src /= 24;
  54         days = src % 7;    src /= 7;
  55         weeks = src;       src = 0;
  56
  57         x = 0;
  58         if (weeks) {
  59                 T(fmt1(weeks, 'W', &dst, &dstlen));
  60                 x++;
  61         }
  62         if (days) {
  63                 T(fmt1(days, 'D', &dst, &dstlen));
  64                 x++;
  65         }
  66         if (hours) {
  67                 T(fmt1(hours, 'H', &dst, &dstlen));
  68                 x++;
  69         }
  70         if (mins) {
  71                 T(fmt1(mins, 'M', &dst, &dstlen));
  72                 x++;
  73         }
  74         if (secs || !(weeks || days || hours || mins)) {
  75                 T(fmt1(secs, 'S', &dst, &dstlen));
  76                 x++;
  77         }
  78
  79         if (x > 1) {
  80                 int ch;
  81
  82                 for (p = odst; (ch = *p) != '\0'; p++)
  83                         if (isascii(ch) && isupper(ch))
  84                                 *p = tolower(ch);
  85         }
  86
  87         return (dst - odst);
  88 }
  89
  90 int
  91 ns_parse_ttl(const char *src, u_long *dst) {
  92         u_long ttl, tmp;
  93         int ch, digits, dirty;
  94
  95         ttl = 0;
  96         tmp = 0;
  97         digits = 0;
  98         dirty = 0;
  99         while ((ch = *src++) != '\0') {
 100                 if (!isascii(ch) || !isprint(ch))
 101                         goto einval;
 102                 if (isdigit(ch)) {
 103                         tmp *= 10;
 104                         tmp += (ch - '0');
 105                         digits++;
 106                         continue;
 107                 }
 108                 if (digits == 0)
 109                         goto einval;
 110                 if (islower(ch))
 111                         ch = toupper(ch);
 112                 switch (ch) {
 113                 case 'W':  tmp *= 7;
 114                         /* FALLTHROUGH */
 115                 case 'D':  tmp *= 24;
 116                         /* FALLTHROUGH */
 117                 case 'H':  tmp *= 60;
 118                         /* FALLTHROUGH */
 119                 case 'M':  tmp *= 60;
 120                         /* FALLTHROUGH */
 121                 case 'S':  break;
 122                 default:   goto einval;
 123                 }
 124                 ttl += tmp;
 125                 tmp = 0;
 126                 digits = 0;
 127                 dirty = 1;
 128         }
 129         if (digits > 0) {
 130                 if (dirty)
 131                         goto einval;
 132                 else
 133                         ttl += tmp;
 134         } else if (!dirty)
 135                 goto einval;
 136         *dst = ttl;
 137         return (0);
 138
 139  einval:
 140         errno = EINVAL;
 141         return (-1);
 142 }
 143
 144 /* Private. */
 145
 146 static int
 147 fmt1(int t, char s, char **buf, size_t *buflen) {
 148         char tmp[50];
 149         size_t len;
 150
 151         len = SPRINTF((tmp, "%d%c", t, s));
 152         if (len + 1 > *buflen)
 153                 return (-1);
 154         strcpy(*buf, tmp);
 155         *buf += len;
 156         *buflen -= len;
 157         return (0);
 158 }
 159
 160 /*! \file */