stdlib.java

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/*
 *  Copyright 2000-2005 The Apache Software Foundation
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 */

package org.apache.tomcat.jni;

/** Stdlib
 *
 * @author Mladen Turk
 * @version $Revision: 300969 $, $Date: 2005-07-12 10:56:11 -0400 (Tue, 12 Jul 2005) $
 */

public class Stdlib {

    /**
     * Read from plain memory
     * @param dst Destination byte array
     * @param src Source memory address
     * @param sz Number of bytes to copy.
     */
    public static native boolean memread(byte [] dst, long src, int sz);

    /**
     * Write to plain memory
     * @param dst Destination memory address
     * @param src Source byte array
     * @param sz Number of bytes to copy.
     */
    public static native boolean memwrite(long dst, byte [] src, int sz);

    /**
     * Sets buffers to a specified character
     * @param dst Destination memory address
     * @param c Character to set.
     * @param sz Number of characters.
     */
    public static native boolean memset(long dst, int c, int sz);

    /**
     * Allocates memory blocks.
     * @param sz Bytes to allocate.
     */
    public static native long malloc(int sz);

    /**
     * Reallocate memory blocks.
     * @param mem Pointer to previously allocated memory block.
     * @param sz New size in bytes.
     */
    public static native long realloc(long mem, int sz);

    /**
     * Allocates an array in memory with elements initialized to 0.
     * @param num Number of elements.
     * @param sz Length in bytes of each element.
     */
    public static native long calloc(long num, int sz);

    /**
     * Deallocates or frees a memory block.
     * @param mem Previously allocated memory block to be freed.
     */
    public static native void free(long mem);

    /**
     * Get current process pid.
     * @return current pid or < 1 in case of error.
     */
    public static native int getpid();

    /**
     * Get current process parent pid.
     * @return parent pid or < 1 in case of error.
     */
    public static native int getppid();

}