1 /*
2 * Copyright (c) 2000, 2010, 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 "java_lang_Integer.h"
35 #include "nio.h"
36 #include "nio_util.h"
37 #include <nativehelper/JNIHelp.h>
38
39
40 #define NATIVE_METHOD(className, functionName, signature) \
41 { #functionName, signature, (void*)(className ## _ ## functionName) }
42
43 static jfieldID fd_fdID; /* for jint 'fd' in java.io.FileDescriptor */
44
IOUtil_initIDs(JNIEnv * env)45 static void IOUtil_initIDs(JNIEnv *env)
46 {
47 jclass clazz = (*env)->FindClass(env, "java/io/FileDescriptor");
48 CHECK_NULL(clazz);
49 fd_fdID = (*env)->GetFieldID(env, clazz, "descriptor", "I");
50 CHECK_NULL(fd_fdID);
51 }
52
53 JNIEXPORT jboolean JNICALL
IOUtil_randomBytes(JNIEnv * env,jclass clazz,jbyteArray randArray)54 IOUtil_randomBytes(JNIEnv *env, jclass clazz,
55 jbyteArray randArray)
56 {
57 JNU_ThrowByName(env, "java/lang/UnsupportedOperationException", NULL);
58 return JNI_FALSE;
59 }
60
61 JNIEXPORT jint JNICALL
IOUtil_fdVal(JNIEnv * env,jclass clazz,jobject fdo)62 IOUtil_fdVal(JNIEnv *env, jclass clazz, jobject fdo)
63 {
64 return (*env)->GetIntField(env, fdo, fd_fdID);
65 }
66
67 JNIEXPORT void JNICALL
IOUtil_setfdVal(JNIEnv * env,jclass clazz,jobject fdo,jint val)68 IOUtil_setfdVal(JNIEnv *env, jclass clazz, jobject fdo, jint val)
69 {
70 (*env)->SetIntField(env, fdo, fd_fdID, val);
71 }
72
73 static int
configureBlocking(int fd,jboolean blocking)74 configureBlocking(int fd, jboolean blocking)
75 {
76 int flags = fcntl(fd, F_GETFL);
77 int newflags = blocking ? (flags & ~O_NONBLOCK) : (flags | O_NONBLOCK);
78
79 return (flags == newflags) ? 0 : fcntl(fd, F_SETFL, newflags);
80 }
81
82 JNIEXPORT void JNICALL
IOUtil_configureBlocking(JNIEnv * env,jclass clazz,jobject fdo,jboolean blocking)83 IOUtil_configureBlocking(JNIEnv *env, jclass clazz,
84 jobject fdo, jboolean blocking)
85 {
86 if (configureBlocking(fdval(env, fdo), blocking) < 0)
87 JNU_ThrowIOExceptionWithLastError(env, "Configure blocking failed");
88 }
89
90 JNIEXPORT jlong JNICALL
IOUtil_makePipe(JNIEnv * env,jobject this,jboolean blocking)91 IOUtil_makePipe(JNIEnv *env, jobject this, jboolean blocking)
92 {
93 int fd[2];
94
95 if (pipe(fd) < 0) {
96 JNU_ThrowIOExceptionWithLastError(env, "Pipe failed");
97 return 0;
98 }
99 if (blocking == JNI_FALSE) {
100 if ((configureBlocking(fd[0], JNI_FALSE) < 0)
101 || (configureBlocking(fd[1], JNI_FALSE) < 0)) {
102 JNU_ThrowIOExceptionWithLastError(env, "Configure blocking failed");
103 close(fd[0]);
104 close(fd[1]);
105 return 0;
106 }
107 }
108 return ((jlong) fd[0] << 32) | (jlong) fd[1];
109 }
110
111 JNIEXPORT jboolean JNICALL
IOUtil_drain(JNIEnv * env,jclass cl,jint fd)112 IOUtil_drain(JNIEnv *env, jclass cl, jint fd)
113 {
114 char buf[128];
115 int tn = 0;
116
117 for (;;) {
118 int n = read(fd, buf, sizeof(buf));
119 tn += n;
120 if ((n < 0) && (errno != EAGAIN))
121 JNU_ThrowIOExceptionWithLastError(env, "Drain");
122 if (n == (int)sizeof(buf))
123 continue;
124 return (tn > 0) ? JNI_TRUE : JNI_FALSE;
125 }
126 }
127
128 JNIEXPORT jint JNICALL
IOUtil_fdLimit(JNIEnv * env,jclass this)129 IOUtil_fdLimit(JNIEnv *env, jclass this)
130 {
131 struct rlimit rlp;
132 if (getrlimit(RLIMIT_NOFILE, &rlp) < 0) {
133 JNU_ThrowIOExceptionWithLastError(env, "getrlimit failed");
134 return -1;
135 }
136 // Android-changed: Remove the rlimit < 0 check.
137 if (rlp.rlim_max > java_lang_Integer_MAX_VALUE) {
138 return java_lang_Integer_MAX_VALUE;
139 } else {
140 return (jint)rlp.rlim_max;
141 }
142 }
143
144 JNIEXPORT jint JNICALL
IOUtil_iovMax(JNIEnv * env,jclass this)145 IOUtil_iovMax(JNIEnv *env, jclass this)
146 {
147 jlong iov_max = sysconf(_SC_IOV_MAX);
148 if (iov_max == -1)
149 iov_max = 16;
150 return (jint)iov_max;
151 }
152
153 /* Declared in nio_util.h for use elsewhere in NIO */
154
155 jint
convertReturnVal(JNIEnv * env,jint n,jboolean reading)156 convertReturnVal(JNIEnv *env, jint n, jboolean reading)
157 {
158 if (n > 0) /* Number of bytes written */
159 return n;
160 else if (n == 0) {
161 if (reading) {
162 return IOS_EOF; /* EOF is -1 in javaland */
163 } else {
164 return 0;
165 }
166 }
167 else if (errno == EAGAIN)
168 return IOS_UNAVAILABLE;
169 else if (errno == EINTR)
170 return IOS_INTERRUPTED;
171 else {
172 const char *msg = reading ? "Read failed" : "Write failed";
173 JNU_ThrowIOExceptionWithLastError(env, msg);
174 return IOS_THROWN;
175 }
176 }
177
178 /* Declared in nio_util.h for use elsewhere in NIO */
179
180 jlong
convertLongReturnVal(JNIEnv * env,jlong n,jboolean reading)181 convertLongReturnVal(JNIEnv *env, jlong n, jboolean reading)
182 {
183 if (n > 0) /* Number of bytes written */
184 return n;
185 else if (n == 0) {
186 if (reading) {
187 return IOS_EOF; /* EOF is -1 in javaland */
188 } else {
189 return 0;
190 }
191 }
192 else if (errno == EAGAIN)
193 return IOS_UNAVAILABLE;
194 else if (errno == EINTR)
195 return IOS_INTERRUPTED;
196 else {
197 const char *msg = reading ? "Read failed" : "Write failed";
198 JNU_ThrowIOExceptionWithLastError(env, msg);
199 return IOS_THROWN;
200 }
201 }
202
203 jint
fdval(JNIEnv * env,jobject fdo)204 fdval(JNIEnv *env, jobject fdo)
205 {
206 return (*env)->GetIntField(env, fdo, fd_fdID);
207 }
208
209 static JNINativeMethod gMethods[] = {
210 NATIVE_METHOD(IOUtil, iovMax, "()I"),
211 NATIVE_METHOD(IOUtil, fdLimit, "()I"),
212 NATIVE_METHOD(IOUtil, drain, "(I)Z"),
213 NATIVE_METHOD(IOUtil, makePipe, "(Z)J"),
214 NATIVE_METHOD(IOUtil, configureBlocking, "(Ljava/io/FileDescriptor;Z)V"),
215 NATIVE_METHOD(IOUtil, setfdVal, "(Ljava/io/FileDescriptor;I)V"),
216 NATIVE_METHOD(IOUtil, fdVal, "(Ljava/io/FileDescriptor;)I"),
217 NATIVE_METHOD(IOUtil, randomBytes, "([B)Z"),
218 };
219
register_sun_nio_ch_IOUtil(JNIEnv * env)220 void register_sun_nio_ch_IOUtil(JNIEnv* env) {
221 jniRegisterNativeMethods(env, "sun/nio/ch/IOUtil", gMethods, NELEM(gMethods));
222
223 IOUtil_initIDs(env);
224 }
225