1 /*
   2  * Copyright (c) 1997, 2009, 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.Inflater
  28  */
  29 
  30 #include <stdio.h>
  31 #include <stdlib.h>
  32 #include <errno.h>
  33 #include <string.h>
  34 #include "jlong.h"
  35 #include "jni.h"
  36 #include "jvm.h"
  37 #include "jni_util.h"
  38 #include "zlib.h"
  39 #include "java_util_zip_Inflater.h"
  40 
  41 #define MIN2(x, y)  ((x) < (y) ? (x) : (y))
  42 
  43 #define ThrowDataFormatException(env, msg) \
  44         JNU_ThrowByName(env, "java/util/zip/DataFormatException", msg)
  45 
  46 static jfieldID needDictID;
  47 static jfieldID finishedID;
  48 static jfieldID bufID, offID, lenID;
  49 
  50 JNIEXPORT void JNICALL
  51 Java_java_util_zip_Inflater_initIDs(JNIEnv *env, jclass cls)
  52 {
  53     needDictID = (*env)->GetFieldID(env, cls, "needDict", "Z");
  54     finishedID = (*env)->GetFieldID(env, cls, "finished", "Z");
  55     bufID = (*env)->GetFieldID(env, cls, "buf", "[B");
  56     offID = (*env)->GetFieldID(env, cls, "off", "I");
  57     lenID = (*env)->GetFieldID(env, cls, "len", "I");
  58 }
  59 
  60 JNIEXPORT jlong JNICALL
  61 Java_java_util_zip_Inflater_init(JNIEnv *env, jclass cls, jboolean nowrap)
  62 {
  63     z_stream *strm = calloc(1, sizeof(z_stream));
  64 
  65     if (strm == 0) {
  66         JNU_ThrowOutOfMemoryError(env, 0);
  67         return jlong_zero;
  68     } else {
  69         char *msg;
  70         switch (inflateInit2(strm, nowrap ? -MAX_WBITS : MAX_WBITS)) {
  71           case Z_OK:
  72             return ptr_to_jlong(strm);
  73           case Z_MEM_ERROR:
  74             free(strm);
  75             JNU_ThrowOutOfMemoryError(env, 0);
  76             return jlong_zero;
  77           default:
  78             msg = strm->msg;
  79             free(strm);
  80             JNU_ThrowInternalError(env, msg);
  81             return jlong_zero;
  82         }
  83     }
  84 }
  85 
  86 JNIEXPORT void JNICALL
  87 Java_java_util_zip_Inflater_setDictionary(JNIEnv *env, jclass cls, jlong addr,
  88                                           jarray b, jint off, jint len)
  89 {
  90     Bytef *buf = (*env)->GetPrimitiveArrayCritical(env, b, 0);
  91     int res;
  92     if (buf == 0) /* out of memory */
  93         return;
  94     res = inflateSetDictionary(jlong_to_ptr(addr), buf + off, len);
  95     (*env)->ReleasePrimitiveArrayCritical(env, b, buf, 0);
  96     switch (res) {
  97     case Z_OK:
  98         break;
  99     case Z_STREAM_ERROR:
 100     case Z_DATA_ERROR:
 101         JNU_ThrowIllegalArgumentException(env, ((z_stream *)jlong_to_ptr(addr))->msg);
 102         break;
 103     default:
 104         JNU_ThrowInternalError(env, ((z_stream *)jlong_to_ptr(addr))->msg);
 105         break;
 106     }
 107 }
 108 
 109 JNIEXPORT jint JNICALL
 110 Java_java_util_zip_Inflater_inflateBytes(JNIEnv *env, jobject this, jlong addr,
 111                                          jarray b, jint off, jint len)
 112 {
 113     z_stream *strm = jlong_to_ptr(addr);
 114 
 115     jarray this_buf = (jarray)(*env)->GetObjectField(env, this, bufID);
 116     jint this_off = (*env)->GetIntField(env, this, offID);
 117     jint this_len = (*env)->GetIntField(env, this, lenID);
 118     jbyte *in_buf;
 119     jbyte *out_buf;
 120     int ret;
 121     /*
 122      * Avoid excess copying.
 123      *   zlib stream usually has a few bytes of overhead for header info
 124      *   (depends on the underlying data)
 125      *
 126      *   (a) 5 bytes per 16KB
 127      *   (b) 6 bytes for entire stream
 128      *   (c) 4 bytes for gzip header
 129      *   (d) 2 bytes for crc
 130      *
 131      * Use 20 bytes as the "safe cutoff" number.
 132      */
 133     jint in_len = MIN2(this_len, len + 20);
 134     jint consumed;
 135 
 136     in_buf = (jbyte *) malloc(in_len);
 137     if (in_buf == 0) {
 138         if (in_len != 0)
 139             JNU_ThrowOutOfMemoryError(env, 0);
 140         return 0;
 141     }
 142     (*env)->GetByteArrayRegion(env, this_buf, this_off, in_len, in_buf);
 143 
 144     out_buf = (jbyte *) malloc(len);
 145     if (out_buf == 0) {
 146         free(in_buf);
 147         if (len != 0)
 148             JNU_ThrowOutOfMemoryError(env, 0);
 149         return 0;
 150     }
 151 
 152     strm->next_in  = (Bytef *) in_buf;
 153     strm->next_out = (Bytef *) out_buf;
 154     strm->avail_in  = in_len;
 155     strm->avail_out = len;
 156     ret = inflate(strm, Z_PARTIAL_FLUSH);
 157 
 158     if (ret == Z_STREAM_END || ret == Z_OK) {
 159         (*env)->SetByteArrayRegion(env, b, off, len - strm->avail_out, out_buf);
 160     }
 161     free(out_buf);
 162     free(in_buf);
 163 
 164     switch (ret) {
 165     case Z_STREAM_END:
 166         (*env)->SetBooleanField(env, this, finishedID, JNI_TRUE);
 167         /* fall through */
 168     case Z_OK:
 169         consumed = in_len - strm->avail_in;
 170         (*env)->SetIntField(env, this, offID, this_off + consumed);
 171         (*env)->SetIntField(env, this, lenID, this_len - consumed);
 172         return len - strm->avail_out;
 173     case Z_NEED_DICT:
 174         (*env)->SetBooleanField(env, this, needDictID, JNI_TRUE);
 175         /* Might have consumed some input here! */
 176         consumed = in_len - strm->avail_in;
 177         (*env)->SetIntField(env, this, offID, this_off + consumed);
 178         (*env)->SetIntField(env, this, lenID, this_len - consumed);
 179         return 0;
 180     case Z_BUF_ERROR:
 181         return 0;
 182     case Z_DATA_ERROR:
 183         ThrowDataFormatException(env, strm->msg);
 184         return 0;
 185     case Z_MEM_ERROR:
 186         JNU_ThrowOutOfMemoryError(env, 0);
 187         return 0;
 188     default:
 189         JNU_ThrowInternalError(env, strm->msg);
 190         return 0;
 191     }
 192 }
 193 
 194 JNIEXPORT jint JNICALL
 195 Java_java_util_zip_Inflater_getAdler(JNIEnv *env, jclass cls, jlong addr)
 196 {
 197     return ((z_stream *)jlong_to_ptr(addr))->adler;
 198 }
 199 
 200 JNIEXPORT jlong JNICALL
 201 Java_java_util_zip_Inflater_getBytesRead(JNIEnv *env, jclass cls, jlong addr)
 202 {
 203     return ((z_stream *)jlong_to_ptr(addr))->total_in;
 204 }
 205 
 206 JNIEXPORT jlong JNICALL
 207 Java_java_util_zip_Inflater_getBytesWritten(JNIEnv *env, jclass cls, jlong addr)
 208 {
 209     return ((z_stream *)jlong_to_ptr(addr))->total_out;
 210 }
 211 
 212 JNIEXPORT void JNICALL
 213 Java_java_util_zip_Inflater_reset(JNIEnv *env, jclass cls, jlong addr)
 214 {
 215     if (inflateReset(jlong_to_ptr(addr)) != Z_OK) {
 216         JNU_ThrowInternalError(env, 0);
 217     }
 218 }
 219 
 220 JNIEXPORT void JNICALL
 221 Java_java_util_zip_Inflater_end(JNIEnv *env, jclass cls, jlong addr)
 222 {
 223     if (inflateEnd(jlong_to_ptr(addr)) == Z_STREAM_ERROR) {
 224         JNU_ThrowInternalError(env, 0);
 225     } else {
 226         free(jlong_to_ptr(addr));
 227     }
 228 }