/*

 * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

#include <stdio.h>

#include <stdlib.h>

#include <unistd.h>

#include <errno.h>

#ifdef __solaris__

#include <sys/systeminfo.h>

#endif

#include <string.h>

#include "jni.h"

#ifndef MAXDNAME

#define MAXDNAME                1025

#endif

/*

 * Class:     jdk_dns_conf_ResolverConfiguration

 * Method:    localDomain0

 * Signature: ()Ljava/lang/String;

 */

JNIEXPORT jstring JNICALL

Java_jdk_dns_conf_DnsResolverConfiguration_localDomain0(JNIEnv *env, jclass cls)

{

    /*

     * On Solaris the LOCALDOMAIN environment variable has absolute

     * priority.

     */

#ifdef __solaris__

    {

        char *cp = getenv("LOCALDOMAIN");

        if (cp != NULL) {

            jstring s = (*env)->NewStringUTF(env, cp);

            return s;

        }

    }

#endif

    return (jstring)NULL;

}

/*

 * Class:     jdk_dns_conf_DnsResolverConfiguration

 * Method:    loadConfig0

 * Signature: ()Ljava/lang/String;

 */

JNIEXPORT jstring JNICALL

Java_jdk_dns_conf_DnsResolverConfiguration_fallbackDomain0(JNIEnv *env, jclass cls)

{

    char buf[MAXDNAME];

    /*

     * On Solaris if domain or search directives aren't specified

     * in /etc/resolv.conf then sysinfo or gethostname is used to

     * determine the domain name.

     *

     * On Linux if domain or search directives aren't specified

     * then gethostname is used.

     */

#ifdef __solaris__

    {

        int ret = sysinfo(SI_SRPC_DOMAIN, buf, sizeof(buf));

        if ((ret > 0) && (ret<sizeof(buf))) {

            char *cp;

            jstring s;

            if (buf[0] == '+') {

                buf[0] = '.';

            }

            cp = strchr(buf, '.');

            if (cp == NULL) {

                s = (*env)->NewStringUTF(env, buf);

            } else {

                s = (*env)->NewStringUTF(env, cp+1);

            }

            return s;

        }

    }

#endif

    if (gethostname(buf, sizeof(buf)) == 0) {

        char *cp;

        /* gethostname doesn't null terminate if insufficient space */

        buf[sizeof(buf)-1] = '\0';

        cp = strchr(buf, '.');

        if (cp != NULL) {

            jstring s = (*env)->NewStringUTF(env, cp+1);

            return s;

        }

    }

    return (jstring)NULL;

}