1 /*
2  * Copyright (c) 1997, 2012, Oracle and/or its affiliates. All rights reserved.
3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4  *
5  * This code is free software; you can redistribute it and/or modify it
6  * under the terms of the GNU General Public License version 2 only, as
7  * published by the Free Software Foundation.  Oracle designates this
8  * particular file as subject to the "Classpath" exception as provided
9  * by Oracle in the LICENSE file that accompanied this code.
10  *
11  * This code is distributed in the hope that it will be useful, but WITHOUT
12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14  * version 2 for more details (a copy is included in the LICENSE file that
15  * accompanied this code).
16  *
17  * You should have received a copy of the GNU General Public License version
18  * 2 along with this work; if not, write to the Free Software Foundation,
19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20  *
21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22  * or visit www.oracle.com if you need additional information or have any
23  * questions.
24  */
25 
26 /*
27  * Native method support for java.util.zip.CRC32
28  */
29 
30 #include <nativehelper/JNIHelp.h>
31 #include "jni.h"
32 #include "jni_util.h"
33 #include <zlib.h>
34 
35 
36 #define NATIVE_METHOD(className, functionName, signature) \
37 { #functionName, signature, (void*)(className ## _ ## functionName) }
38 
39 JNIEXPORT jint JNICALL
CRC32_update(JNIEnv * env,jclass cls,jint crc,jint b)40 CRC32_update(JNIEnv *env, jclass cls, jint crc, jint b)
41 {
42     Bytef buf[1];
43 
44     buf[0] = (Bytef)b;
45     return crc32(crc, buf, 1);
46 }
47 
48 JNIEXPORT jint JNICALL
CRC32_updateBytes(JNIEnv * env,jclass cls,jint crc,jarray b,jint off,jint len)49 CRC32_updateBytes(JNIEnv *env, jclass cls, jint crc,
50                                      jarray b, jint off, jint len)
51 {
52     Bytef *buf = (*env)->GetPrimitiveArrayCritical(env, b, 0);
53     if (buf) {
54         crc = crc32(crc, buf + off, len);
55         (*env)->ReleasePrimitiveArrayCritical(env, b, buf, 0);
56     }
57     return crc;
58 }
59 
60 JNIEXPORT jint JNICALL
ZIP_CRC32(jint crc,const jbyte * buf,jint len)61 ZIP_CRC32(jint crc, const jbyte *buf, jint len)
62 {
63     return crc32(crc, (Bytef*)buf, len);
64 }
65 
66 JNIEXPORT jint JNICALL
CRC32_updateByteBuffer(JNIEnv * env,jclass cls,jint crc,jlong address,jint off,jint len)67 CRC32_updateByteBuffer(JNIEnv *env, jclass cls, jint crc,
68                                           jlong address, jint off, jint len)
69 {
70     Bytef *buf = (Bytef *)jlong_to_ptr(address);
71     if (buf) {
72         crc = crc32(crc, buf + off, len);
73     }
74     return crc;
75 }
76 
77 static JNINativeMethod gMethods[] = {
78   NATIVE_METHOD(CRC32, update, "(II)I"),
79   NATIVE_METHOD(CRC32, updateBytes, "(I[BII)I"),
80   NATIVE_METHOD(CRC32, updateByteBuffer, "(IJII)I"),
81 };
82 
register_java_util_zip_CRC32(JNIEnv * env)83 void register_java_util_zip_CRC32(JNIEnv* env) {
84   jniRegisterNativeMethods(env, "java/util/zip/CRC32", gMethods, NELEM(gMethods));
85 }
86