1 /*
2 * Copyright (c) 2000, 2018, 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 <sys/types.h>
27 #include <string.h>
28 #include <sys/resource.h>
29
30 #include "jni.h"
31 #include "jni_util.h"
32 #include "jvm.h"
33 #include "jlong.h"
34 #include "sun_nio_ch_IOUtil.h"
35 #include "java_lang_Integer.h"
36 #include "nio.h"
37 #include "nio_util.h"
38 #include "net_util.h"
39
40 static jfieldID fd_fdID; /* for jint 'fd' in java.io.FileDescriptor */
41
42
43 JNIEXPORT void JNICALL
44 Java_sun_nio_ch_IOUtil_initIDs(JNIEnv *env, jclass clazz)
45 {
46 CHECK_NULL(clazz = (*env)->FindClass(env, "java/io/FileDescriptor"));
47 CHECK_NULL(fd_fdID = (*env)->GetFieldID(env, clazz, "fd", "I"));
48 initInetAddressIDs(env);
49 }
50
51 JNIEXPORT jboolean JNICALL
52 Java_sun_nio_ch_IOUtil_randomBytes(JNIEnv *env, jclass clazz,
53 jbyteArray randArray)
54 {
55 JNU_ThrowByName(env, "java/lang/UnsupportedOperationException", NULL);
56 return JNI_FALSE;
57 }
58
59 JNIEXPORT jint JNICALL
60 Java_sun_nio_ch_IOUtil_fdVal(JNIEnv *env, jclass clazz, jobject fdo)
61 {
62 return (*env)->GetIntField(env, fdo, fd_fdID);
63 }
64
65 JNIEXPORT void JNICALL
66 Java_sun_nio_ch_IOUtil_setfdVal(JNIEnv *env, jclass clazz, jobject fdo, jint val)
67 {
68 (*env)->SetIntField(env, fdo, fd_fdID, val);
69 }
70
71 static int
72 configureBlocking(int fd, jboolean blocking)
73 {
74 int flags = fcntl(fd, F_GETFL);
75 int newflags = blocking ? (flags & ~O_NONBLOCK) : (flags | O_NONBLOCK);
76
77 return (flags == newflags) ? 0 : fcntl(fd, F_SETFL, newflags);
78 }
79
80 JNIEXPORT void JNICALL
81 Java_sun_nio_ch_IOUtil_configureBlocking(JNIEnv *env, jclass clazz,
82 jobject fdo, jboolean blocking)
83 {
84 if (configureBlocking(fdval(env, fdo), blocking) < 0)
85 JNU_ThrowIOExceptionWithLastError(env, "Configure blocking failed");
86 }
87
88 JNIEXPORT jlong JNICALL
89 Java_sun_nio_ch_IOUtil_makePipe(JNIEnv *env, jobject this, jboolean blocking)
90 {
91 int fd[2];
92
93 if (pipe(fd) < 0) {
94 JNU_ThrowIOExceptionWithLastError(env, "Pipe failed");
95 return 0;
96 }
97 if (blocking == JNI_FALSE) {
98 if ((configureBlocking(fd[0], JNI_FALSE) < 0)
99 || (configureBlocking(fd[1], JNI_FALSE) < 0)) {
100 JNU_ThrowIOExceptionWithLastError(env, "Configure blocking failed");
101 close(fd[0]);
102 close(fd[1]);
103 return 0;
104 }
105 }
106 return ((jlong) fd[0] << 32) | (jlong) fd[1];
107 }
108
109 JNIEXPORT jboolean JNICALL
110 Java_sun_nio_ch_IOUtil_drain(JNIEnv *env, jclass cl, jint fd)
111 {
112 char buf[128];
113 int tn = 0;
114
115 for (;;) {
116 int n = read(fd, buf, sizeof(buf));
117 tn += n;
118 if ((n < 0) && (errno != EAGAIN && errno != EWOULDBLOCK))
119 JNU_ThrowIOExceptionWithLastError(env, "Drain");
120 if (n == (int)sizeof(buf))
121 continue;
122 return (tn > 0) ? JNI_TRUE : JNI_FALSE;
123 }
124 }
125
126 JNIEXPORT jint JNICALL
127 Java_sun_nio_ch_IOUtil_fdLimit(JNIEnv *env, jclass this)
128 {
129 struct rlimit rlp;
130 if (getrlimit(RLIMIT_NOFILE, &rlp) < 0) {
131 JNU_ThrowIOExceptionWithLastError(env, "getrlimit failed");
132 return -1;
133 }
134 if (rlp.rlim_max < 0 || rlp.rlim_max > java_lang_Integer_MAX_VALUE) {
135 return java_lang_Integer_MAX_VALUE;
136 } else {
137 return (jint)rlp.rlim_max;
138 }
139 }
140
141 JNIEXPORT jint JNICALL
142 Java_sun_nio_ch_IOUtil_iovMax(JNIEnv *env, jclass this)
143 {
144 jlong iov_max = sysconf(_SC_IOV_MAX);
145 if (iov_max == -1)
146 iov_max = 16;
147 return (jint)iov_max;
148 }
149
150 /* Declared in nio_util.h for use elsewhere in NIO */
151
152 jint
153 convertReturnVal(JNIEnv *env, jint n, jboolean reading)
154 {
155 if (n > 0) /* Number of bytes written */
156 return n;
157 else if (n == 0) {
158 if (reading) {
159 return IOS_EOF; /* EOF is -1 in javaland */
160 } else {
161 return 0;
162 }
163 }
164 else if (errno == EAGAIN || errno == EWOULDBLOCK)
165 return IOS_UNAVAILABLE;
166 else if (errno == EINTR)
167 return IOS_INTERRUPTED;
168 else {
169 const char *msg = reading ? "Read failed" : "Write failed";
170 JNU_ThrowIOExceptionWithLastError(env, msg);
171 return IOS_THROWN;
172 }
173 }
174
175 /* Declared in nio_util.h for use elsewhere in NIO */
176
177 jlong
178 convertLongReturnVal(JNIEnv *env, jlong n, jboolean reading)
179 {
180 if (n > 0) /* Number of bytes written */
181 return n;
182 else if (n == 0) {
183 if (reading) {
184 return IOS_EOF; /* EOF is -1 in javaland */
185 } else {
186 return 0;
187 }
188 }
189 else if (errno == EAGAIN || errno == EWOULDBLOCK)
190 return IOS_UNAVAILABLE;
191 else if (errno == EINTR)
192 return IOS_INTERRUPTED;
193 else {
194 const char *msg = reading ? "Read failed" : "Write failed";
195 JNU_ThrowIOExceptionWithLastError(env, msg);
196 return IOS_THROWN;
197 }
198 }
199
200 jint
201 fdval(JNIEnv *env, jobject fdo)
202 {
203 return (*env)->GetIntField(env, fdo, fd_fdID);
204 }