usr/src/lib/libnisdb/db_vers.cc

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or http://www.opensolaris.org/os/licensing.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
  19  *
  20  * CDDL HEADER END
  21  */
  22 /*
  23  *      db_vers.cc
  24  *
  25  *      Copyright (c) 1988-2000 by Sun Microsystems, Inc.
  26  *      All Rights Reserved.
  27  */
  28
  29 #pragma ident   "%Z%%M% %I%     %E% SMI"
  30
  31 #include <stdio.h>
  32 #include <string.h>
  33
  34 #include "db_headers.h"
  35 #include "db_vers.h"
  36 #include "nisdb_mt.h"
  37
  38 const long unsigned MAXLOW = 32768*32768;
  39
  40 /* Constructor that makes copy of 'other'. */
  41 vers::vers(vers* other)
  42 {
  43         INITRW(vers);
  44         assign(other);
  45 }
  46
  47 void
  48 vers::assign(vers* other)
  49 {
  50         WRITELOCKV(this, "w vers::assign");
  51         if (other == NULL) {
  52                 syslog(LOG_ERR, "vers::vers: making copy of null vers?");
  53                 vers_high = vers_low = time_sec = time_usec = 0;
  54         } else {
  55                 time_sec = other->time_sec;
  56                 time_usec = other->time_usec;
  57                 vers_low = other->vers_low;
  58                 vers_high = other->vers_high;
  59         }
  60         WRITEUNLOCKV(this, "wu vers::assign");
  61 }
  62
  63 /*
  64  * Creates new 'vers' with next higher minor version.
  65  * If minor version exceeds MAXLOW, bump up major version instead.
  66  * Set timestamp to that of the current time.
  67  */
  68 vers*
  69 vers::nextminor()
  70 {
  71         READLOCK(this, NULL, "r vers::nextminor");
  72
  73         vers * newvers = new vers;
  74
  75         if (newvers == NULL) {
  76                 READUNLOCK(this, NULL, "ru vers::nextminor DB_MEMORY_LIMIT");
  77                 FATAL3("vers::nextminor: cannot allocation space",
  78                         DB_MEMORY_LIMIT, NULL);
  79         }
  80
  81         struct timeval mt;
  82         gettimeofday(&mt, NULL);
  83
  84         newvers->time_sec = (unsigned int) mt.tv_sec;
  85         newvers->time_usec = (unsigned int) mt.tv_usec;
  86         newvers->vers_low = (this->vers_low + 1);
  87         newvers->vers_high = (this->vers_high);
  88
  89         if (newvers->vers_low >= MAXLOW){
  90                 newvers->vers_high++;
  91                 newvers->vers_low = 0;
  92         }
  93
  94         READUNLOCK(this, newvers, "ru vers::nextminor");
  95         return (newvers);
  96 }
  97
  98 /*
  99  * Creates new 'vers' with next higher major version.
 100  * Set timestamp to that of the current time.
 101  */
 102 vers*
 103 vers::nextmajor()
 104 {
 105         READLOCK(this, NULL, "r vers::nextmajor");
 106
 107         vers * newvers = new vers;
 108
 109         if (newvers == NULL) {
 110                 READUNLOCK(this, NULL, "ru vers::nextmajor DB_MEMORY_LIMIT");
 111                 FATAL3("vers::nextminor: cannot allocation space",
 112                         DB_MEMORY_LIMIT, NULL);
 113         }
 114
 115         struct timeval mt;
 116         gettimeofday(&mt, NULL);
 117
 118         newvers->time_sec = (unsigned int) mt.tv_sec;
 119         newvers->time_usec = (unsigned int) mt.tv_usec;
 120         newvers->vers_low = 0;
 121         newvers->vers_high = (this->vers_high+1);
 122
 123         READUNLOCK(this, newvers, "ru vers::nextmajor");
 124         return (newvers);
 125 }
 126
 127 /*
 128  * Predicate indicating whether this vers is earlier than 'other' in
 129  * terms of version numbers.
 130 */
 131 bool_t
 132 vers::earlier_than(vers *other)
 133 {
 134         int     ret, lret;
 135
 136         if (other == NULL) {
 137                 syslog(LOG_ERR,
 138                         "vers::earlier_than: comparing against null vers");
 139                 return (FALSE);
 140         }
 141
 142         READLOCK(this, FALSE, "r vers::earlier_than");
 143         READLOCKNR(other, lret, "r other vers::earlier_than");
 144         if (lret != 0) {
 145                 READUNLOCK(this, FALSE, "ru + r other vers::earlier_than");
 146                 return (FALSE);
 147         }
 148
 149         if (other->vers_high > vers_high) ret = TRUE;
 150         else if (other->vers_high < vers_high) ret = FALSE;
 151         else if (other->vers_low > vers_low) ret = TRUE;
 152         else ret = FALSE;
 153
 154         READUNLOCKNR(other, lret, "ru other vers::earlier_than");
 155         READUNLOCK(this, ret, ((lret != 0) ?
 156                                 "ru + ru other vers::earlier_than" :
 157                                 "ru vers::earlier_than"));
 158         return (ret);
 159 }
 160
 161 /* Print the value of this 'vers' to specified file. */
 162 void
 163 vers::print(FILE* file)
 164 {
 165         char *thetime;
 166         thetime = ctime((long *) (&(time_sec)));
 167         thetime[strlen(thetime)-1] = 0;
 168
 169         READLOCKV(this, "r vers::print");
 170         fprintf(file, "version=%u.%u %s:%u",
 171                 vers_high,
 172                 vers_low,
 173                 /* time_sec, */
 174                 thetime,
 175                 time_usec);
 176         READUNLOCKV(this, "ru vers::print");
 177 }
 178
 179 void
 180 vers::zero() {
 181         WRITELOCKV(this, "r vers::zero");
 182         vers_high = vers_low = time_sec = time_usec = 0;
 183         WRITEUNLOCKV(this, "ru vers::zero");
 184 }
 185
 186 bool_t
 187 vers::equal( vers *other) {
 188         READLOCK(this, FALSE, "r vers::equal");
 189         bool_t ret = other != NULL &&
 190                 vers_high == other->vers_high &&
 191                 vers_low == other->vers_low &&
 192                 time_sec == other->time_sec &&
 193                 time_usec == other->time_usec;
 194         READUNLOCK(this, ret, "ru vers::equal");
 195         return (ret);
 196 };