libzfs_jni/common/libzfs_jni_util.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

#include "libzfs_jni_util.h"
#include <strings.h>

/*
 * Package-private functions
 */

void
zjni_free_array(void **array, zjni_free_f freefunc)
{
    if (array != NULL) {
        if (freefunc != NULL) {
            int i;
            for (i = 0; array[i] != NULL; i++) {
                freefunc(array[i]);
            }
        }
        free(array);
    }
}

/*PRINTFLIKE2*/
void
zjni_throw_exception(JNIEnv *env, const char *fmt, ...)
{
    char error[1024];
    va_list ap;
    jclass class_UnsupportedOperationException;

    va_start(ap, fmt);
    (void) vsnprintf(error, sizeof (error), fmt, ap);
    va_end(ap);

    class_UnsupportedOperationException =
        (*env)->FindClass(env, "java/lang/UnsupportedOperationException");

    (*env)->ThrowNew(env, class_UnsupportedOperationException, error);
}

jstring
zjni_get_matched_string(JNIEnv *env, char *name, regmatch_t *match)
{
    jstring stringUTF = NULL;
    if (match->rm_so != -1 && match->rm_eo != -1) {
        char *end = name + match->rm_eo;
        char tmp = *end;
        *end = '\0';
        stringUTF = (*env)->NewStringUTF(env, name + match->rm_so);
        *end = tmp;
    }
    return (stringUTF);
}

void
zjni_get_dataset_from_snapshot(const char *snapshot, char *dataset,
    size_t len)
{
    char *at;
    (void) strncpy(dataset, snapshot, len);
    at = strchr(dataset, '@');
    if (at != NULL) {
        *at = '\0';
    }
}

/* Convert a zjni_Collection to a (Java) array */
jobjectArray
zjni_Collection_to_array(JNIEnv *env, zjni_Collection_t *list, char *class)
{
    /* Get size of zjni_Collection */
    jint length = (*env)->CallIntMethod(
        env, ((zjni_Object_t *)list)->object,
        ((zjni_Collection_t *)list)->method_size);

    /* Create array to hold elements of list */
    jobjectArray array = (*env)->NewObjectArray(
        env, length, (*env)->FindClass(env, class), NULL);

    /* Copy list elements to array */
    return (*env)->CallObjectMethod(env, ((zjni_Object_t *)list)->object,
        ((zjni_Collection_t *)list)->method_toArray, array);
}

/* Create a zjni_Collection */
void
new_Collection(JNIEnv *env, zjni_Collection_t *collection)
{
    zjni_Object_t *object = (zjni_Object_t *)collection;

    collection->method_add = (*env)->GetMethodID(
        env, object->class, "add", "(Ljava/lang/Object;)Z");

    collection->method_size =
        (*env)->GetMethodID(env, object->class, "size", "()I");

    collection->method_toArray =
        (*env)->GetMethodID(env, object->class, "toArray",
        "([Ljava/lang/Object;)[Ljava/lang/Object;");
}

/* Create an zjni_ArrayList */
void
zjni_new_ArrayList(JNIEnv *env, zjni_ArrayList_t *list)
{
    zjni_Object_t *object = (zjni_Object_t *)list;

    if (object->object == NULL) {
        object->class = (*env)->FindClass(env, "java/util/ArrayList");

        object->constructor =
            (*env)->GetMethodID(env, object->class, "<init>", "()V");

        object->object = (*env)->NewObject(
            env, object->class, object->constructor);
    }

    new_Collection(env, (zjni_Collection_t *)list);
}

/* Create an zjni_DatasetSet */
void
zjni_new_DatasetSet(JNIEnv *env, zjni_DatasetSet_t *list)
{
    zjni_Object_t *object = (zjni_Object_t *)list;

    if (object->object == NULL) {
        object->class = (*env)->FindClass(
            env, "com/sun/zfs/common/util/DatasetSet");

        object->constructor =
            (*env)->GetMethodID(env, object->class, "<init>", "()V");

        object->object = (*env)->NewObject(
            env, object->class, object->constructor);
    }

    new_Collection(env, (zjni_Collection_t *)list);
}

jobject
zjni_int_to_boolean(JNIEnv *env, uint64_t value)
{
    jclass class_Boolean = (*env)->FindClass(
        env, "java/lang/Boolean");

    jfieldID id = (*env)->GetStaticFieldID(env, class_Boolean,
        value ? "TRUE" : "FALSE", "Ljava/lang/Boolean;");

    return (*env)->GetStaticObjectField(env, class_Boolean, id);
}

jobject
zjni_int_to_enum(JNIEnv *env, int value, char *class_name,
    char *default_field_name, zjni_field_mapping_t *mapping)
{
    int i;
    char *field_name;
    jclass class;
    jfieldID id;
    jobject field_value = NULL;
    int found = 0;

    for (i = 0; mapping[i].name != NULL; i++) {
        if (value == mapping[i].value) {
            field_name = mapping[i].name;
            found = 1;
            break;
        }
    }

    if (!found) {
        field_name = default_field_name;
    }

    if (field_name != NULL) {
        char signature[1024];

        (void) snprintf(signature, sizeof (signature), "L%s;",
            class_name);

        class = (*env)->FindClass(env, class_name);
        id = (*env)->GetStaticFieldID(
            env, class, field_name, signature);
        field_value = (*env)->GetStaticObjectField(env, class, id);
    }

    return (field_value);
}

jobject
zjni_str_to_long(JNIEnv *env, char *str)
{
    jobject value = NULL;
    jclass class_Long = (*env)->FindClass(env, "java/lang/Long");

    jmethodID method_valueOf = (*env)->GetStaticMethodID(env,
        class_Long, "valueOf", "(Ljava/lang/String;)Ljava/lang/Long;");

    jstring utf = (*env)->NewStringUTF(env, str);

    /* May throw a NumberFormatException */
    value = (*env)->CallStaticObjectMethod(
        env, class_Long, method_valueOf, utf);

    return (value);
}

jobject
zjni_long_to_Long(JNIEnv *env, uint64_t value)
{
    jclass class_Long = (*env)->FindClass(env, "java/lang/Long");

    jmethodID constructor_Long = (*env)->GetMethodID(
        env, class_Long, "<init>", "(J)V");

    jobject obj = (*env)->NewObject(
        env, class_Long, constructor_Long, value);

    return (obj);
}

jobject
zjni_str_to_date(JNIEnv *env, char *str)
{
    jobject date = NULL;
    jclass class_Long = (*env)->FindClass(env, "java/lang/Long");

    jmethodID method_parseLong = (*env)->GetStaticMethodID(env,
        class_Long, "parseLong", "(Ljava/lang/String;)J");

    jstring utf = (*env)->NewStringUTF(env, str);
    if (utf != NULL) {

        /* May throw a NumberFormatException */
        jlong time = (*env)->CallStaticLongMethod(
            env, class_Long, method_parseLong, utf);

        if ((*env)->ExceptionOccurred(env) == NULL) {

            jclass class_Date = (*env)->FindClass(env,
                "java/util/Date");

            jmethodID constructor_Date = (*env)->GetMethodID(
                env, class_Date, "<init>", "(J)V");

            /* Date constructor takes epoch milliseconds */
            time *= 1000;

            date = (*env)->NewObject(
                env, class_Date, constructor_Date, time);
        }
    }

    return (date);
}

jobjectArray
zjni_c_string_array_to_java(JNIEnv *env, char **array, int n)
{
    int i;
    jclass class_String = (*env)->FindClass(env, "java/lang/String");
    jobjectArray jarray =
        (*env)->NewObjectArray(env, n, class_String, NULL);

    for (i = 0; i < n; i++) {
        jstring elementUTF = (*env)->NewStringUTF(env, array[i]);
        (void) (*env)->SetObjectArrayElement(env, jarray, i,
            elementUTF);
    }

    return (jarray);
}

/*
 * Converts the non-null elements of the given Java String array into
 * a NULL-terminated char* array.  When done, each element and then
 * the array itself must be free()d.  Returns NULL if memory could not
 * be allocated.
 */
char **
zjni_java_string_array_to_c(JNIEnv *env, jobjectArray array)
{
    int i, n;
    jsize length = (*env)->GetArrayLength(env, array);
    char **result = (char **)calloc(length + 1, sizeof (char *));

    if (result != NULL) {
        for (i = 0, n = 0; i < length; i++) {
            jboolean isCopy;

            /* Retrive String from array */
            jstring string = (*env)->GetObjectArrayElement(
                env, array, i);

            if (string != NULL) {
                /* Convert to char* */
                const char *converted =
                    (*env)->GetStringUTFChars(env, string,
                    &isCopy);

                result[n] = strdup(converted);

                if (isCopy == JNI_TRUE) {
                    /* Free chars in Java space */
                    (void) (*env)->ReleaseStringUTFChars(
                        env, string, converted);
                }

                if (result[n++] == NULL) {
                    /* strdup failed */
                    zjni_free_array((void *)result, free);
                    break;
                }
            }
        }

        /* Terminate array */
        result[n] = NULL;
    }

    return (result);
}

/*
 * Counts the number of elements in the given NULL-terminated array.
 * Does not include the terminating NULL in the count.
 */
int
zjni_count_elements(void **array)
{
    int i = 0;
    if (array != NULL) {
        for (; array[i] != NULL; i++);
    }
    return (i);
}

/*
 * Get a handle to the next nvpair with the specified name and data
 * type in the list following the given nvpair.
 *
 * This function is needed because the nvlist_lookup_* routines can
 * only be used with nvlists allocated with NV_UNIQUE_NAME or
 * NV_UNIQUE_NAME_TYPE, ie. lists of unique name/value pairs.
 *
 * Some variation of this function will likely appear in the libnvpair
 * library per 4981923.
 *
 * @param       nvl
 *              the nvlist_t to search
 *
 * @param       name
 *              the string key for the pair to find in the list, or
 *              NULL to match any name
 *
 * @param       type
 *              the data type for the pair to find in the list, or
 *              DATA_TYPE_UNKNOWN to match any type
 *
 * @param       nvp
 *              the pair to search from in the list, or NULL to search
 *              from the beginning of the list
 *
 * @return      the next nvpair in the list matching the given
 *              criteria, or NULL if no matching nvpair is found
 */
nvpair_t *
zjni_nvlist_walk_nvpair(nvlist_t *nvl, const char *name, data_type_t type,
    nvpair_t *nvp)
{
    /* For each nvpair in the list following nvp... */
    while ((nvp = nvlist_next_nvpair(nvl, nvp)) != NULL) {

        /* Does this pair's name match the given name? */
        if ((name == NULL || strcmp(nvpair_name(nvp), name) == 0) &&

            /* Does this pair's type match the given type? */
            (type == DATA_TYPE_UNKNOWN || type == nvpair_type(nvp))) {
            return (nvp);
        }
    }

    return (NULL);
}