external/bsd/bind/dist/lib/dns/lib.c

   1 /*      $NetBSD$        */
   2
   3 /*
   4  * Copyright (C) 2004, 2005, 2007, 2009  Internet Systems Consortium, Inc. ("ISC")
   5  * Copyright (C) 1999-2001  Internet Software Consortium.
   6  *
   7  * Permission to use, copy, modify, and/or distribute this software for any
   8  * purpose with or without fee is hereby granted, provided that the above
   9  * copyright notice and this permission notice appear in all copies.
  10  *
  11  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
  12  * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
  13  * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
  14  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
  15  * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
  16  * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
  17  * PERFORMANCE OF THIS SOFTWARE.
  18  */
  19
  20 /* Id: lib.c,v 1.19 2009/09/03 00:12:23 each Exp */
  21
  22 /*! \file */
  23
  24 #include <config.h>
  25
  26 #include <stddef.h>
  27
  28 #include <isc/hash.h>
  29 #include <isc/mem.h>
  30 #include <isc/msgcat.h>
  31 #include <isc/mutex.h>
  32 #include <isc/once.h>
  33 #include <isc/util.h>
  34
  35 #include <dns/db.h>
  36 #include <dns/ecdb.h>
  37 #include <dns/lib.h>
  38 #include <dns/result.h>
  39
  40 #include <dst/dst.h>
  41
  42
  43 /***
  44  *** Globals
  45  ***/
  46
  47 LIBDNS_EXTERNAL_DATA unsigned int                       dns_pps = 0U;
  48 LIBDNS_EXTERNAL_DATA isc_msgcat_t *                     dns_msgcat = NULL;
  49
  50
  51 /***
  52  *** Private
  53  ***/
  54
  55 static isc_once_t               msgcat_once = ISC_ONCE_INIT;
  56
  57
  58 /***
  59  *** Functions
  60  ***/
  61
  62 static void
  63 open_msgcat(void) {
  64         isc_msgcat_open("libdns.cat", &dns_msgcat);
  65 }
  66
  67 void
  68 dns_lib_initmsgcat(void) {
  69
  70         /*
  71          * Initialize the DNS library's message catalog, dns_msgcat, if it
  72          * has not already been initialized.
  73          */
  74
  75         RUNTIME_CHECK(isc_once_do(&msgcat_once, open_msgcat) == ISC_R_SUCCESS);
  76 }
  77
  78 static isc_once_t init_once = ISC_ONCE_INIT;
  79 static isc_mem_t *dns_g_mctx = NULL;
  80 #ifndef BIND9
  81 static dns_dbimplementation_t *dbimp = NULL;
  82 #endif
  83 static isc_boolean_t initialize_done = ISC_FALSE;
  84 static isc_mutex_t reflock;
  85 static unsigned int references = 0;
  86
  87 static void
  88 initialize(void) {
  89         isc_result_t result;
  90
  91         REQUIRE(initialize_done == ISC_FALSE);
  92
  93         result = isc_mem_create(0, 0, &dns_g_mctx);
  94         if (result != ISC_R_SUCCESS)
  95                 return;
  96         dns_result_register();
  97 #ifndef BIND9
  98         result = dns_ecdb_register(dns_g_mctx, &dbimp);
  99         if (result != ISC_R_SUCCESS)
 100                 goto cleanup_mctx;
 101 #endif
 102         result = isc_hash_create(dns_g_mctx, NULL, DNS_NAME_MAXWIRE);
 103         if (result != ISC_R_SUCCESS)
 104                 goto cleanup_db;
 105
 106         result = dst_lib_init(dns_g_mctx, NULL, 0);
 107         if (result != ISC_R_SUCCESS)
 108                 goto cleanup_hash;
 109
 110         result = isc_mutex_init(&reflock);
 111         if (result != ISC_R_SUCCESS)
 112                 goto cleanup_dst;
 113
 114         initialize_done = ISC_TRUE;
 115         return;
 116
 117   cleanup_dst:
 118         dst_lib_destroy();
 119   cleanup_hash:
 120         isc_hash_destroy();
 121   cleanup_db:
 122 #ifndef BIND9
 123         dns_ecdb_unregister(&dbimp);
 124   cleanup_mctx:
 125 #endif
 126         isc_mem_detach(&dns_g_mctx);
 127 }
 128
 129 isc_result_t
 130 dns_lib_init(void) {
 131         isc_result_t result;
 132
 133         /*
 134          * Since this routine is expected to be used by a normal application,
 135          * it should be better to return an error, instead of an emergency
 136          * abort, on any failure.
 137          */
 138         result = isc_once_do(&init_once, initialize);
 139         if (result != ISC_R_SUCCESS)
 140                 return (result);
 141
 142         if (!initialize_done)
 143                 return (ISC_R_FAILURE);
 144
 145         LOCK(&reflock);
 146         references++;
 147         UNLOCK(&reflock);
 148
 149         return (ISC_R_SUCCESS);
 150 }
 151
 152 void
 153 dns_lib_shutdown(void) {
 154         isc_boolean_t cleanup_ok = ISC_FALSE;
 155
 156         LOCK(&reflock);
 157         if (--references == 0)
 158                 cleanup_ok = ISC_TRUE;
 159         UNLOCK(&reflock);
 160
 161         if (!cleanup_ok)
 162                 return;
 163
 164         dst_lib_destroy();
 165         isc_hash_destroy();
 166 #ifndef BIND9
 167         dns_ecdb_unregister(&dbimp);
 168 #endif
 169         isc_mem_detach(&dns_g_mctx);
 170 }