1 /*
   2  * Copyright (c) 1997, 2016, 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 #include <errno.h>
  26 #include <stdlib.h>
  27 #include <string.h>
  28 
  29 #include "net_util.h"
  30 
  31 #include "java_net_SocketOutputStream.h"
  32 
  33 #define min(a, b)       ((a) < (b) ? (a) : (b))
  34 
  35 /*
  36  * SocketOutputStream
  37  */
  38 
  39 static jfieldID IO_fd_fdID;
  40 
  41 /*
  42  * Class:     java_net_SocketOutputStream
  43  * Method:    init
  44  * Signature: ()V
  45  */
  46 JNIEXPORT void JNICALL
  47 Java_java_net_SocketOutputStream_init(JNIEnv *env, jclass cls) {
  48     IO_fd_fdID = NET_GetFileDescriptorID(env);
  49 }
  50 
  51 /*
  52  * Class:     java_net_SocketOutputStream
  53  * Method:    socketWrite0
  54  * Signature: (Ljava/io/FileDescriptor;[BII)V
  55  */
  56 JNIEXPORT void JNICALL
  57 Java_java_net_SocketOutputStream_socketWrite0(JNIEnv *env, jobject this,
  58                                               jobject fdObj,
  59                                               jbyteArray data,
  60                                               jint off, jint len) {
  61     char *bufP;
  62     char BUF[MAX_BUFFER_LEN];
  63     int buflen;
  64     int fd;
  65 
  66     if (IS_NULL(fdObj)) {
  67         JNU_ThrowByName(env, "java/net/SocketException", "Socket closed");
  68         return;
  69     } else {
  70         fd = (*env)->GetIntField(env, fdObj, IO_fd_fdID);
  71         /* Bug 4086704 - If the Socket associated with this file descriptor
  72          * was closed (sysCloseFD), the file descriptor is set to -1.
  73          */
  74         if (fd == -1) {
  75             JNU_ThrowByName(env, "java/net/SocketException", "Socket closed");
  76             return;
  77         }
  78 
  79     }
  80 
  81     if (len <= MAX_BUFFER_LEN) {
  82         bufP = BUF;
  83         buflen = MAX_BUFFER_LEN;
  84     } else {
  85         buflen = min(MAX_HEAP_BUFFER_LEN, len);
  86         bufP = (char *)malloc((size_t)buflen);
  87 
  88         /* if heap exhausted resort to stack buffer */
  89         if (bufP == NULL) {
  90             bufP = BUF;
  91             buflen = MAX_BUFFER_LEN;
  92         }
  93     }
  94 
  95     while(len > 0) {
  96         int loff = 0;
  97         int chunkLen = min(buflen, len);
  98         int llen = chunkLen;
  99         (*env)->GetByteArrayRegion(env, data, off, chunkLen, (jbyte *)bufP);
 100 
 101         if ((*env)->ExceptionCheck(env)) {
 102             break;
 103         } else {
 104             while(llen > 0) {
 105                 int n = NET_Send(fd, bufP + loff, llen, 0);
 106                 if (n > 0) {
 107                     llen -= n;
 108                     loff += n;
 109                     continue;
 110                 }
 111                 JNU_ThrowByNameWithMessageAndLastError
 112                     (env, "java/net/SocketException", "Write failed");
 113                 if (bufP != BUF) {
 114                     free(bufP);
 115                 }
 116                 return;
 117             }
 118             len -= chunkLen;
 119             off += chunkLen;
 120         }
 121     }
 122 
 123     if (bufP != BUF) {
 124         free(bufP);
 125     }
 126 }