/*

 * 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 "jni.h"

#include "jni_util.h"

#include "jvm.h"

#include "jlong.h"

#include <sys/param.h>

#include <sys/mount.h>

#ifdef ST_RDONLY

#define statfs statvfs

#define getfsstat getvfsstat

#define f_flags f_flag

#define ISREADONLY ST_RDONLY

#else

#define ISREADONLY MNT_RDONLY

#endif

#include <stdlib.h>

#include <string.h>

static jfieldID entry_name;

static jfieldID entry_dir;

static jfieldID entry_fstype;

static jfieldID entry_options;

struct fsstat_iter {

    struct statfs *buf;

    int pos;

    int nentries;

};

#include "sun_nio_fs_BsdNativeDispatcher.h"

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);

    }

}

/**

 * Initialize jfieldIDs

 */

JNIEXPORT void JNICALL

Java_sun_nio_fs_BsdNativeDispatcher_initIDs(JNIEnv* env, jclass this)

{

    jclass clazz;

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

    CHECK_NULL(clazz);

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

    CHECK_NULL(entry_name);

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

    CHECK_NULL(entry_dir);

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

    CHECK_NULL(entry_fstype);

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

    CHECK_NULL(entry_options);

}

JNIEXPORT jlong JNICALL

Java_sun_nio_fs_BsdNativeDispatcher_getfsstat(JNIEnv* env, jclass this)

{

    int nentries;

    size_t bufsize;

    struct fsstat_iter *iter = malloc(sizeof(*iter));

    if (iter == NULL) {

        JNU_ThrowOutOfMemoryError(env, "native heap");

        return 0;

    }

    iter->pos = 0;

    iter->nentries = 0;

    iter->buf = NULL;

    nentries = getfsstat(NULL, 0, MNT_NOWAIT);

    if (nentries <= 0) {

        free(iter);

        throwUnixException(env, errno);

        return 0;

    }

    // It's possible that a new filesystem gets mounted between

    // the first getfsstat and the second so loop until consistant

    while (nentries != iter->nentries) {

        if (iter->buf != NULL)

            free(iter->buf);

        bufsize = nentries * sizeof(struct statfs);

        iter->nentries = nentries;

        iter->buf = malloc(bufsize);

        if (iter->buf == NULL) {

            free(iter);

            JNU_ThrowOutOfMemoryError(env, "native heap");

            return 0;

        }

        nentries = getfsstat(iter->buf, bufsize, MNT_WAIT);

        if (nentries <= 0) {

            free(iter->buf);

            free(iter);

            throwUnixException(env, errno);

            return 0;

        }

    }

    return (jlong)iter;

}

JNIEXPORT jint JNICALL

Java_sun_nio_fs_BsdNativeDispatcher_fsstatEntry(JNIEnv* env, jclass this,

    jlong value, jobject entry)

{

    struct fsstat_iter *iter = jlong_to_ptr(value);

    jsize len;

    jbyteArray bytes;

    char* name;

    char* dir;

    char* fstype;

    char* options;

    dev_t dev;

    if (iter == NULL || iter->pos >= iter->nentries)

       return -1;

    name = iter->buf[iter->pos].f_mntfromname;

    dir = iter->buf[iter->pos].f_mntonname;

    fstype = iter->buf[iter->pos].f_fstypename;

    if (iter->buf[iter->pos].f_flags & ISREADONLY)

        options="ro";

    else

        options="";

    iter->pos++;

    len = strlen(name);

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

    if (bytes == NULL)

        return -1;

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

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

    len = strlen(dir);

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

    if (bytes == NULL)

        return -1;

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

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

    len = strlen(fstype);

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

    if (bytes == NULL)

        return -1;

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

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

    len = strlen(options);

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

    if (bytes == NULL)

        return -1;

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

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

    return 0;

}

JNIEXPORT void JNICALL

Java_sun_nio_fs_BsdNativeDispatcher_endfsstat(JNIEnv* env, jclass this, jlong value)

{

    struct fsstat_iter *iter = jlong_to_ptr(value);

    if (iter != NULL) {

        free(iter->buf);

        free(iter);

    }

}