usr/src/cmd/backup/dump/unctime.c

   1 /*
   2  * Copyright (c) 1998,2001 by Sun Microsystems, Inc.
   3  * All rights reserved.
   4  */
   5
   6 /*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
   7 /*        All Rights Reserved   */
   8
   9 /*
  10  * Copyright (c) 1980 Regents of the University of California.
  11  * All rights reserved.  The Berkeley software License Agreement
  12  * specifies the terms and conditions for redistribution.
  13  */
  14
  15 #pragma ident   "%Z%%M% %I%     %E% SMI"
  16
  17 #include <sys/types.h>
  18 #include <time.h>
  19 #include <string.h>
  20 #include <stdlib.h>
  21 /*
  22  * Convert a ctime(3) format string into a system format date.
  23  * Return the date thus calculated.
  24  *
  25  * Return -1 if the string is not in ctime format.
  26  */
  27
  28 /*
  29  * Offsets into the ctime string to various parts.
  30  */
  31
  32 #define E_MONTH         4
  33 #define E_DAY           8
  34 #define E_HOUR          11
  35 #define E_MINUTE        14
  36 #define E_SECOND        17
  37 #define E_YEAR          20
  38
  39 #ifdef __STDC__
  40 static int lookup(char *);
  41 static time_t emitl(struct tm *);
  42 #else
  43 static int lookup();
  44 static time_t emitl();
  45 #endif
  46
  47 time_t
  48 unctime(str)
  49         char *str;
  50 {
  51         struct tm then;
  52         char dbuf[30];
  53
  54         /* Definition of ctime(3) is 24 characters + newline + NUL */
  55         (void) strncpy(dbuf, str, 24);
  56         dbuf[24] = '\0';
  57         dbuf[E_MONTH+3] = '\0';
  58         then.tm_mon = lookup(&dbuf[E_MONTH]);
  59         if (then.tm_mon < 0) {
  60                 return (-1);
  61         }
  62         then.tm_mday = atoi(&dbuf[E_DAY]);
  63         then.tm_hour = atoi(&dbuf[E_HOUR]);
  64         then.tm_min = atoi(&dbuf[E_MINUTE]);
  65         then.tm_sec = atoi(&dbuf[E_SECOND]);
  66         then.tm_year = atoi(&dbuf[E_YEAR]) - 1900;
  67         return (emitl(&then));
  68 }
  69
  70 static char months[] =
  71         "JanFebMarAprMayJunJulAugSepOctNovDec";
  72
  73 static int
  74 lookup(str)
  75         char *str;
  76 {
  77         char *cp, *cp2;
  78
  79         for (cp = months, cp2 = str; *cp != 0; cp += 3)
  80                 if (strncmp(cp, cp2, 3) == 0)
  81                         /* LINTED ptr arith will give < INT_MAX result */
  82                         return (((int)(cp-months)) / 3);
  83         return (-1);
  84 }
  85 /*
  86  * Routine to convert a localtime(3) format date back into
  87  * a system format date.
  88  */
  89 static time_t
  90 emitl(dp)
  91         struct tm *dp;
  92 {
  93         dp->tm_isdst = -1;
  94         return (mktime(dp));
  95 }