/*

 * Copyright (c) 2008, 2013, Oracle and/or its affiliates. All rights reserved.

 * Copyright 2013 SAP AG. 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 <stdlib.h>

#include <errno.h>

#include <sys/types.h>

#include <sys/mntctl.h>

#include "jni.h"

#include "jni_util.h"

#include "sun_nio_fs_AixNativeDispatcher.h"

static jfieldID entry_name;

static jfieldID entry_dir;

static jfieldID entry_fstype;

static jfieldID entry_options;

static jclass entry_cls;

/**

 * Call this to throw an internal UnixException when a system/library

 * call fails

 */

static void throwUnixException(JNIEnv* env, int errnum) {

    jobject x = JNU_NewObjectByName(env, "sun/nio/fs/UnixException",

        "(I)V", errnum);

    if (x != NULL) {

        (*env)->Throw(env, x);

    }

}

/**

 * Initialization

 */

JNIEXPORT jint JNICALL

Java_sun_nio_fs_AixNativeDispatcher_init(JNIEnv* env, jclass this)

{

    jint flags = 0;

    jclass clazz;

    clazz = (*env)->FindClass(env, "sun/nio/fs/UnixMountEntry");

    if (clazz == NULL) {

        return 0;

    }

    entry_name = (*env)->GetFieldID(env, clazz, "name", "[B");

    entry_dir = (*env)->GetFieldID(env, clazz, "dir", "[B");

    entry_fstype = (*env)->GetFieldID(env, clazz, "fstype", "[B");

    entry_options = (*env)->GetFieldID(env, clazz, "opts", "[B");

    entry_cls = (*env)->NewGlobalRef(env, clazz);

    return 0;

}

/**

 * Special implementation of getextmntent (see SolarisNativeDispatcher.c)

 * that returns all entries at once.

 */

JNIEXPORT jobjectArray JNICALL

Java_sun_nio_fs_AixNativeDispatcher_getmntctl(JNIEnv* env, jclass this)

{

    int must_free_buf = 0;

    char stack_buf[1024];

    char* buffer = stack_buf;

    size_t buffer_size = 1024;

    int num_entries;

    int i;

    jobjectArray ret;

    struct vmount * vm;

    for (i = 0; i < 5; i++) {

        num_entries = mntctl(MCTL_QUERY, buffer_size, buffer);

        if (num_entries != 0) {

            break;

        }

        if (must_free_buf) {

            free(buffer);

        }

        buffer_size *= 8;

        buffer = malloc(buffer_size);

        must_free_buf = 1;

    }

    /* Treat zero entries like errors. */

    if (num_entries <= 0) {

        if (must_free_buf) {

            free(buffer);

        }

        throwUnixException(env, errno);

        return NULL;

    }

    ret = (*env)->NewObjectArray(env, num_entries, entry_cls, NULL);

    if (ret == NULL) {

        if (must_free_buf) {

            free(buffer);

        }

        return NULL;

    }

    vm = (struct vmount*)buffer;

    for (i = 0; i < num_entries; i++) {

        jsize len;

        jbyteArray bytes;

        const char* fstype;

        /* We set all relevant attributes so there is no need to call constructor. */

        jobject entry = (*env)->AllocObject(env, entry_cls);

        if (entry == NULL) {

            if (must_free_buf) {

                free(buffer);

            }

            return NULL;

        }

        (*env)->SetObjectArrayElement(env, ret, i, entry);

        /* vm->vmt_data[...].vmt_size is 32 bit aligned and also includes NULL byte. */

        /* Since we only need the characters, it is necessary to check string size manually. */

        len = strlen((char*)vm + vm->vmt_data[VMT_OBJECT].vmt_off);

        bytes = (*env)->NewByteArray(env, len);

        if (bytes == NULL) {

            if (must_free_buf) {

                free(buffer);

            }

            return NULL;

        }

        (*env)->SetByteArrayRegion(env, bytes, 0, len, (jbyte*)((char *)vm + vm->vmt_data[VMT_OBJECT].vmt_off));

        (*env)->SetObjectField(env, entry, entry_name, bytes);

        len = strlen((char*)vm + vm->vmt_data[VMT_STUB].vmt_off);

        bytes = (*env)->NewByteArray(env, len);

        if (bytes == NULL) {

            if (must_free_buf) {

                free(buffer);

            }

            return NULL;

        }

        (*env)->SetByteArrayRegion(env, bytes, 0, len, (jbyte*)((char *)vm + vm->vmt_data[VMT_STUB].vmt_off));

        (*env)->SetObjectField(env, entry, entry_dir, bytes);

        switch (vm->vmt_gfstype) {

            case MNT_J2:

                fstype = "jfs2";

                break;

            case MNT_NAMEFS:

                fstype = "namefs";

                break;

            case MNT_NFS:

                fstype = "nfs";

                break;

            case MNT_JFS:

                fstype = "jfs";

                break;

            case MNT_CDROM:

                fstype = "cdrom";

                break;

            case MNT_PROCFS:

                fstype = "procfs";

                break;

            case MNT_NFS3:

                fstype = "nfs3";

                break;

            case MNT_AUTOFS:

                fstype = "autofs";

                break;

            case MNT_UDF:

                fstype = "udfs";

                break;

            case MNT_NFS4:

                fstype = "nfs4";

                break;

            case MNT_CIFS:

                fstype = "smbfs";

                break;

            default:

                fstype = "unknown";

        }

        len = strlen(fstype);

        bytes = (*env)->NewByteArray(env, len);

        if (bytes == NULL) {

            if (must_free_buf) {

                free(buffer);

            }

            return NULL;

        }

        (*env)->SetByteArrayRegion(env, bytes, 0, len, (jbyte*)fstype);

        (*env)->SetObjectField(env, entry, entry_fstype, bytes);

        len = strlen((char*)vm + vm->vmt_data[VMT_ARGS].vmt_off);

        bytes = (*env)->NewByteArray(env, len);

        if (bytes == NULL) {

            if (must_free_buf) {

                free(buffer);

            }

            return NULL;

        }

        (*env)->SetByteArrayRegion(env, bytes, 0, len, (jbyte*)((char *)vm + vm->vmt_data[VMT_ARGS].vmt_off));

        (*env)->SetObjectField(env, entry, entry_options, bytes);

        /* goto the next vmount structure: */

        vm = (struct vmount *)((char *)vm + vm->vmt_length);

    }

    if (must_free_buf) {

        free(buffer);

    }

    return ret;

}