1 /*

     2  * Copyright (c) 1996, 2011, 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 #include "jni.h"

    27 #include "jvm.h"

    28 #include "jni_util.h"

    29 #include "jlong.h"

    30 

    31 #include "java_lang_Float.h"

    32 #include "java_lang_Double.h"

    33 #include "java_io_ObjectInputStream.h"

    34 

    35 

    36 /*

    37  * Class:     java_io_ObjectInputStream

    38  * Method:    bytesToFloats

    39  * Signature: ([BI[FII)V

    40  *

    41  * Reconstitutes nfloats float values from their byte representations.  Byte

    42  * values are read from array src starting at offset srcpos; the resulting

    43  * float values are written to array dst starting at dstpos.

    44  */

    45 JNIEXPORT void JNICALL

    46 Java_java_io_ObjectInputStream_bytesToFloats(JNIEnv *env,

    47                                              jclass this,

    48                                              jbyteArray src,

    49                                              jint srcpos,

    50                                              jfloatArray dst,

    51                                              jint dstpos,

    52                                              jint nfloats)

    53 {

    54     union {

    55         int i;

    56         float f;

    57     } u;

    58     jfloat *floats;

    59     jbyte *bytes;

    60     jsize dstend;

    61     jint ival;

    62 

    63     if (nfloats == 0)

    64         return;

    65 

    66     /* fetch source array */

    67     if (src == NULL) {

    68         JNU_ThrowNullPointerException(env, NULL);

    69         return;

    70     }

    71     bytes = (*env)->GetPrimitiveArrayCritical(env, src, NULL);

    72     if (bytes == NULL)          /* exception thrown */

    73         return;

    74 

    75     /* fetch dest array */

    76     if (dst == NULL) {

    77         (*env)->ReleasePrimitiveArrayCritical(env, src, bytes, JNI_ABORT);

    78         JNU_ThrowNullPointerException(env, NULL);

    79         return;

    80     }

    81     floats = (*env)->GetPrimitiveArrayCritical(env, dst, NULL);

    82     if (floats == NULL) {       /* exception thrown */

    83         (*env)->ReleasePrimitiveArrayCritical(env, src, bytes, JNI_ABORT);

    84         return;

    85     }

    86 

    87     /* do conversion */

    88     dstend = dstpos + nfloats;

    89     for ( ; dstpos < dstend; dstpos++) {

    90         ival = ((bytes[srcpos + 0] & 0xFF) << 24) +

    91                ((bytes[srcpos + 1] & 0xFF) << 16) +

    92                ((bytes[srcpos + 2] & 0xFF) << 8) +

    93                ((bytes[srcpos + 3] & 0xFF) << 0);

    94         u.i = (long) ival;

    95         floats[dstpos] = (jfloat) u.f;

    96         srcpos += 4;

    97     }

    98 

    99     (*env)->ReleasePrimitiveArrayCritical(env, src, bytes, JNI_ABORT);

   100     (*env)->ReleasePrimitiveArrayCritical(env, dst, floats, 0);

   101 }

   102 

   103 /*

   104  * Class:     java_io_ObjectInputStream

   105  * Method:    bytesToDoubles

   106  * Signature: ([BI[DII)V

   107  *

   108  * Reconstitutes ndoubles double values from their byte representations.

   109  * Byte values are read from array src starting at offset srcpos; the

   110  * resulting double values are written to array dst starting at dstpos.

   111  */

   112 JNIEXPORT void JNICALL

   113 Java_java_io_ObjectInputStream_bytesToDoubles(JNIEnv *env,

   114                                               jclass this,

   115                                               jbyteArray src,

   116                                               jint srcpos,

   117                                               jdoubleArray dst,

   118                                               jint dstpos,

   119                                               jint ndoubles)

   120 

   121 {

   122     union {

   123         jlong l;

   124         double d;

   125     } u;

   126     jdouble *doubles;

   127     jbyte *bytes;

   128     jsize dstend;

   129     jlong lval;

   130 

   131     if (ndoubles == 0)

   132         return;

   133 

   134     /* fetch source array */

   135     if (src == NULL) {

   136         JNU_ThrowNullPointerException(env, NULL);

   137         return;

   138     }

   139     bytes = (*env)->GetPrimitiveArrayCritical(env, src, NULL);

   140     if (bytes == NULL)          /* exception thrown */

   141         return;

   142 

   143     /* fetch dest array */

   144     if (dst == NULL) {

   145         (*env)->ReleasePrimitiveArrayCritical(env, src, bytes, JNI_ABORT);

   146         JNU_ThrowNullPointerException(env, NULL);

   147         return;

   148     }

   149     doubles = (*env)->GetPrimitiveArrayCritical(env, dst, NULL);

   150     if (doubles == NULL) {      /* exception thrown */

   151         (*env)->ReleasePrimitiveArrayCritical(env, src, bytes, JNI_ABORT);

   152         return;

   153     }

   154 

   155     /* do conversion */

   156     dstend = dstpos + ndoubles;

   157     for ( ; dstpos < dstend; dstpos++) {

   158         lval = (((jlong) bytes[srcpos + 0] & 0xFF) << 56) +

   159                (((jlong) bytes[srcpos + 1] & 0xFF) << 48) +

   160                (((jlong) bytes[srcpos + 2] & 0xFF) << 40) +

   161                (((jlong) bytes[srcpos + 3] & 0xFF) << 32) +

   162                (((jlong) bytes[srcpos + 4] & 0xFF) << 24) +

   163                (((jlong) bytes[srcpos + 5] & 0xFF) << 16) +

   164                (((jlong) bytes[srcpos + 6] & 0xFF) << 8) +

   165                (((jlong) bytes[srcpos + 7] & 0xFF) << 0);

   166         jlong_to_jdouble_bits(&lval);

   167         u.l = lval;

   168         doubles[dstpos] = (jdouble) u.d;

   169         srcpos += 8;

   170     }

   171 

   172     (*env)->ReleasePrimitiveArrayCritical(env, src, bytes, JNI_ABORT);

   173     (*env)->ReleasePrimitiveArrayCritical(env, dst, doubles, 0);

   174 }

   175