1 /*
2 * Copyright (c) 2000, 2025, 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 <windows.h>
27 #include <winsock2.h>
28 #include <io.h>
29 #include "jni.h"
30 #include "jni_util.h"
31 #include "jvm.h"
32 #include "jlong.h"
33
34 #include "java_lang_Long.h"
35 #include "nio.h"
36 #include "nio_util.h"
37 #include "net_util.h"
38 #include "sun_nio_ch_IOUtil.h"
39
40 /* field id for jlong 'handle' in java.io.FileDescriptor used for file fds */
41 static jfieldID handle_fdID;
42
43 /* field id for jint 'fd' in java.io.FileDescriptor used for socket fds */
44 static jfieldID fd_fdID;
45
46 JNIEXPORT jboolean JNICALL
47 Java_sun_security_provider_NativeSeedGenerator_nativeGenerateSeed
48 (JNIEnv *env, jclass clazz, jbyteArray randArray);
49
50 /**************************************************************
51 * static method to store field IDs in initializers
52 */
53
54 JNIEXPORT void JNICALL
55 Java_sun_nio_ch_IOUtil_initIDs(JNIEnv *env, jclass clazz)
56 {
57 CHECK_NULL(clazz = (*env)->FindClass(env, "java/io/FileDescriptor"));
58 CHECK_NULL(fd_fdID = (*env)->GetFieldID(env, clazz, "fd", "I"));
59 CHECK_NULL(handle_fdID = (*env)->GetFieldID(env, clazz, "handle", "J"));
60 }
61
62 /**************************************************************
63 * IOUtil.c
64 */
65 JNIEXPORT jboolean JNICALL
66 Java_sun_nio_ch_IOUtil_randomBytes(JNIEnv *env, jclass clazz,
67 jbyteArray randArray)
68 {
69 return
70 Java_sun_security_provider_NativeSeedGenerator_nativeGenerateSeed(env,
71 clazz,
72 randArray);
73 }
74
75 JNIEXPORT jint JNICALL
76 Java_sun_nio_ch_IOUtil_iovMax(JNIEnv *env, jclass this)
77 {
78 return 16;
79 }
80
81 JNIEXPORT jlong JNICALL
82 Java_sun_nio_ch_IOUtil_writevMax(JNIEnv *env, jclass this)
83 {
84 return java_lang_Long_MAX_VALUE;
85 }
86
87 jint
88 convertReturnVal(JNIEnv *env, jint n, jboolean reading)
89 {
90 if (n > 0) /* Number of bytes written */
91 return n;
92 if (n == 0) {
93 if (reading) {
94 return IOS_EOF; /* EOF is -1 in javaland */
95 } else {
96 return 0;
97 }
98 }
99 JNU_ThrowIOExceptionWithLastError(env, "Read/write failed");
100 return IOS_THROWN;
101 }
102
103 jlong
104 convertLongReturnVal(JNIEnv *env, jlong n, jboolean reading)
105 {
106 if (n > 0) /* Number of bytes written */
107 return n;
108 if (n == 0) {
109 if (reading) {
110 return IOS_EOF; /* EOF is -1 in javaland */
111 } else {
112 return 0;
113 }
114 }
115 JNU_ThrowIOExceptionWithLastError(env, "Read/write failed");
116 return IOS_THROWN;
117 }
118
119 JNIEXPORT jint JNICALL
120 Java_sun_nio_ch_IOUtil_fdVal(JNIEnv *env, jclass clazz, jobject fdo)
121 {
122 return fdval(env, fdo);
123 }
124
125 JNIEXPORT void JNICALL
126 Java_sun_nio_ch_IOUtil_setfdVal(JNIEnv *env, jclass clazz, jobject fdo, jint val)
127 {
128 setfdval(env, fdo, val);
129 }
130
131
132 #define SET_BLOCKING 0
133 #define SET_NONBLOCKING 1
134
135 JNIEXPORT void JNICALL
136 Java_sun_nio_ch_IOUtil_configureBlocking(JNIEnv *env, jclass clazz,
137 jint fd, jboolean blocking)
138 {
139 u_long argp;
140 int result = 0;
141
142 if (blocking == JNI_FALSE) {
143 argp = SET_NONBLOCKING;
144 } else {
145 argp = SET_BLOCKING;
146 /* Blocking fd cannot be registered with EventSelect */
147 WSAEventSelect(fd, NULL, 0);
148 }
149 result = ioctlsocket(fd, FIONBIO, &argp);
150 if (result == SOCKET_ERROR) {
151 NET_ThrowNew(env, WSAGetLastError(), "ioctlsocket");
152 }
153 }
154
155 JNIEXPORT jboolean JNICALL
156 Java_sun_nio_ch_IOUtil_drain(JNIEnv *env, jclass cl, jint fd)
157 {
158 char buf[16];
159 jboolean readBytes = JNI_FALSE;
160 for (;;) {
161 int n = recv((SOCKET) fd, buf, sizeof(buf), 0);
162 if (n == SOCKET_ERROR) {
163 if (WSAGetLastError() != WSAEWOULDBLOCK) {
164 JNU_ThrowIOExceptionWithLastError(env, "recv failed");
165 }
166 return readBytes;
167 }
168 if (n <= 0)
169 return readBytes;
170 if (n < (int)sizeof(buf))
171 return JNI_TRUE;
172 readBytes = JNI_TRUE;
173 }
174 }
175
176 JNIEXPORT jint JNICALL
177 Java_sun_nio_ch_IOUtil_write1(JNIEnv *env, jclass cl, jint fd, jbyte b)
178 {
179 int n = send((SOCKET) fd, &b, 1, 0);
180 if (n == SOCKET_ERROR && WSAGetLastError() != WSAEWOULDBLOCK) {
181 JNU_ThrowIOExceptionWithLastError(env, "send failed");
182 return IOS_THROWN;
183 }
184 return (n == 1) ? 1 : 0;
185 }
186
187 /* Note: This function returns the int fd value from file descriptor.
188 It is mostly used for sockets which should use the int fd value.
189 */
190 jint
191 fdval(JNIEnv *env, jobject fdo)
192 {
193 return (*env)->GetIntField(env, fdo, fd_fdID);
194 }
195
196 void
197 setfdval(JNIEnv *env, jobject fdo, jint val)
198 {
199 (*env)->SetIntField(env, fdo, fd_fdID, val);
200 }
201
202 jlong
203 handleval(JNIEnv *env, jobject fdo)
204 {
205 return (*env)->GetLongField(env, fdo, handle_fdID);
206 }