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      1 /*	$NetBSD: lib.c,v 1.1 2024/02/18 20:57:32 christos Exp $	*/
      2 
      3 /*
      4  * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
      5  *
      6  * SPDX-License-Identifier: MPL-2.0
      7  *
      8  * This Source Code Form is subject to the terms of the Mozilla Public
      9  * License, v. 2.0.  If a copy of the MPL was not distributed with this
     10  * file, you can obtain one at https://mozilla.org/MPL/2.0/.
     11  *
     12  * See the COPYRIGHT file distributed with this work for additional
     13  * information regarding copyright ownership.
     14  */
     15 
     16 /*! \file */
     17 
     18 #include <stdbool.h>
     19 #include <stddef.h>
     20 
     21 #include <isc/hash.h>
     22 #include <isc/mem.h>
     23 #include <isc/mutex.h>
     24 #include <isc/once.h>
     25 #include <isc/refcount.h>
     26 #include <isc/util.h>
     27 
     28 #include <dns/db.h>
     29 #include <dns/ecdb.h>
     30 #include <dns/lib.h>
     31 #include <dns/result.h>
     32 
     33 #include <dst/dst.h>
     34 
     35 /***
     36  *** Globals
     37  ***/
     38 
     39 LIBDNS_EXTERNAL_DATA unsigned int dns_pps = 0U;
     40 
     41 /***
     42  *** Functions
     43  ***/
     44 
     45 static isc_once_t init_once = ISC_ONCE_INIT;
     46 static isc_mem_t *dns_g_mctx = NULL;
     47 static dns_dbimplementation_t *dbimp = NULL;
     48 static bool initialize_done = false;
     49 static isc_refcount_t references;
     50 
     51 static void
     52 initialize(void) {
     53 	isc_result_t result;
     54 
     55 	REQUIRE(!initialize_done);
     56 
     57 	isc_refcount_init(&references, 0);
     58 
     59 	isc_mem_create(&dns_g_mctx);
     60 	dns_result_register();
     61 	result = dns_ecdb_register(dns_g_mctx, &dbimp);
     62 	if (result != ISC_R_SUCCESS) {
     63 		goto cleanup_mctx;
     64 	}
     65 
     66 	result = dst_lib_init(dns_g_mctx, NULL);
     67 	if (result != ISC_R_SUCCESS) {
     68 		goto cleanup_db;
     69 	}
     70 
     71 	initialize_done = true;
     72 	return;
     73 
     74 cleanup_db:
     75 	if (dbimp != NULL) {
     76 		dns_ecdb_unregister(&dbimp);
     77 	}
     78 cleanup_mctx:
     79 	if (dns_g_mctx != NULL) {
     80 		isc_mem_detach(&dns_g_mctx);
     81 	}
     82 }
     83 
     84 isc_result_t
     85 dns_lib_init(void) {
     86 	isc_result_t result;
     87 
     88 	/*
     89 	 * Since this routine is expected to be used by a normal application,
     90 	 * it should be better to return an error, instead of an emergency
     91 	 * abort, on any failure.
     92 	 */
     93 	result = isc_once_do(&init_once, initialize);
     94 	if (result != ISC_R_SUCCESS) {
     95 		return (result);
     96 	}
     97 
     98 	if (!initialize_done) {
     99 		return (ISC_R_FAILURE);
    100 	}
    101 
    102 	isc_refcount_increment0(&references);
    103 
    104 	return (ISC_R_SUCCESS);
    105 }
    106 
    107 void
    108 dns_lib_shutdown(void) {
    109 	if (isc_refcount_decrement(&references) == 1) {
    110 		dst_lib_destroy();
    111 
    112 		isc_refcount_destroy(&references);
    113 
    114 		if (dbimp != NULL) {
    115 			dns_ecdb_unregister(&dbimp);
    116 		}
    117 		if (dns_g_mctx != NULL) {
    118 			isc_mem_detach(&dns_g_mctx);
    119 		}
    120 	}
    121 }
    122