| /* |
| * Copyright (c) 1997, 2016, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| #include <malloc.h> |
| |
| #include "net_util.h" |
| |
| #include "java_net_SocketOutputStream.h" |
| |
| /************************************************************************ |
| * SocketOutputStream |
| */ |
| static jfieldID IO_fd_fdID; |
| |
| /* |
| * Class: java_net_SocketOutputStream |
| * Method: init |
| * Signature: ()V |
| */ |
| JNIEXPORT void JNICALL |
| Java_java_net_SocketOutputStream_init(JNIEnv *env, jclass cls) { |
| IO_fd_fdID = NET_GetFileDescriptorID(env); |
| } |
| |
| /* |
| * Class: java_net_SocketOutputStream |
| * Method: socketWrite |
| * Signature: (Ljava/io/FileDescriptor;[BII)V |
| */ |
| JNIEXPORT void JNICALL |
| Java_java_net_SocketOutputStream_socketWrite0(JNIEnv *env, jobject this, |
| jobject fdObj, jbyteArray data, |
| jint off, jint len) { |
| char *bufP; |
| char BUF[MAX_BUFFER_LEN]; |
| int buflen; |
| int fd; |
| |
| if (IS_NULL(fdObj)) { |
| JNU_ThrowByName(env, JNU_JAVANETPKG "SocketException", "Socket closed"); |
| return; |
| } else { |
| fd = (*env)->GetIntField(env, fdObj, IO_fd_fdID); |
| } |
| if (IS_NULL(data)) { |
| JNU_ThrowNullPointerException(env, "data argument"); |
| return; |
| } |
| |
| /* |
| * Use stack allocate buffer if possible. For large sizes we allocate |
| * an intermediate buffer from the heap (up to a maximum). If heap is |
| * unavailable just use our stack buffer. |
| */ |
| if (len <= MAX_BUFFER_LEN) { |
| bufP = BUF; |
| buflen = MAX_BUFFER_LEN; |
| } else { |
| buflen = min(MAX_HEAP_BUFFER_LEN, len); |
| bufP = (char *)malloc((size_t)buflen); |
| if (bufP == NULL) { |
| bufP = BUF; |
| buflen = MAX_BUFFER_LEN; |
| } |
| } |
| |
| while(len > 0) { |
| int loff = 0; |
| int chunkLen = min(buflen, len); |
| int llen = chunkLen; |
| int retry = 0; |
| |
| (*env)->GetByteArrayRegion(env, data, off, chunkLen, (jbyte *)bufP); |
| if ((*env)->ExceptionCheck(env)) { |
| break; |
| } else { |
| while(llen > 0) { |
| int n = send(fd, bufP + loff, llen, 0); |
| if (n > 0) { |
| llen -= n; |
| loff += n; |
| continue; |
| } |
| |
| /* |
| * Due to a bug in Windows Sockets (observed on NT and Windows |
| * 2000) it may be necessary to retry the send. The issue is that |
| * on blocking sockets send/WSASend is supposed to block if there |
| * is insufficient buffer space available. If there are a large |
| * number of threads blocked on write due to congestion then it's |
| * possile to hit the NT/2000 bug whereby send returns WSAENOBUFS. |
| * The workaround we use is to retry the send. If we have a |
| * large buffer to send (>2k) then we retry with a maximum of |
| * 2k buffer. If we hit the issue with <=2k buffer then we backoff |
| * for 1 second and retry again. We repeat this up to a reasonable |
| * limit before bailing out and throwing an exception. In load |
| * conditions we've observed that the send will succeed after 2-3 |
| * attempts but this depends on network buffers associated with |
| * other sockets draining. |
| */ |
| if (WSAGetLastError() == WSAENOBUFS) { |
| if (llen > MAX_BUFFER_LEN) { |
| buflen = MAX_BUFFER_LEN; |
| chunkLen = MAX_BUFFER_LEN; |
| llen = MAX_BUFFER_LEN; |
| continue; |
| } |
| if (retry >= 30) { |
| JNU_ThrowByName(env, JNU_JAVANETPKG "SocketException", |
| "No buffer space available - exhausted attempts to queue buffer"); |
| if (bufP != BUF) { |
| free(bufP); |
| } |
| return; |
| } |
| Sleep(1000); |
| retry++; |
| continue; |
| } |
| |
| /* |
| * Send failed - can be caused by close or write error. |
| */ |
| if (WSAGetLastError() == WSAENOTSOCK) { |
| JNU_ThrowByName(env, JNU_JAVANETPKG "SocketException", "Socket closed"); |
| } else { |
| NET_ThrowCurrent(env, "socket write error"); |
| } |
| if (bufP != BUF) { |
| free(bufP); |
| } |
| return; |
| } |
| len -= chunkLen; |
| off += chunkLen; |
| } |
| } |
| |
| if (bufP != BUF) { |
| free(bufP); |
| } |
| } |