1 /*
2  * Copyright (c) 2000, 2012, 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 "jni.h"
27 #include "jni_util.h"
28 #include "jvm.h"
29 #include "jlong.h"
30 #include "sun_nio_ch_FileDispatcherImpl.h"
31 #include "java_lang_Long.h"
32 #include <sys/types.h>
33 #include <sys/socket.h>
34 #include <fcntl.h>
35 #include <sys/uio.h>
36 #include <unistd.h>
37 #if defined(__linux__)
38 #include <linux/fs.h>
39 #include <sys/ioctl.h>
40 #endif
41 #include "nio.h"
42 #include "nio_util.h"
43 #include <nativehelper/JNIHelp.h>
44 
45 #define NATIVE_METHOD(className, functionName, signature) \
46 { #functionName, signature, (void*)(className ## _ ## functionName) }
47 
48 // Android-changed: Fuchsia: Alias *64 on Fuchsia builds. http://b/119496969
49 // #ifdef _ALLBSD_SOURCE
50 #if defined(_ALLBSD_SOURCE) || defined(__Fuchsia__)
51 #define stat64 stat
52 #define flock64 flock
53 #define off64_t off_t
54 #define F_SETLKW64 F_SETLKW
55 #define F_SETLK64 F_SETLK
56 
57 #define pread64 pread
58 #define pwrite64 pwrite
59 #define ftruncate64 ftruncate
60 #define fstat64 fstat
61 
62 #define fdatasync fsync
63 #endif
64 
65 JNIEXPORT jint JNICALL
FileDispatcherImpl_read0(JNIEnv * env,jclass clazz,jobject fdo,jlong address,jint len)66 FileDispatcherImpl_read0(JNIEnv *env, jclass clazz,
67                              jobject fdo, jlong address, jint len)
68 {
69     jint fd = fdval(env, fdo);
70     void *buf = (void *)jlong_to_ptr(address);
71 
72     return convertReturnVal(env, read(fd, buf, len), JNI_TRUE);
73 }
74 
75 JNIEXPORT jint JNICALL
FileDispatcherImpl_pread0(JNIEnv * env,jclass clazz,jobject fdo,jlong address,jint len,jlong offset)76 FileDispatcherImpl_pread0(JNIEnv *env, jclass clazz, jobject fdo,
77                             jlong address, jint len, jlong offset)
78 {
79     jint fd = fdval(env, fdo);
80     void *buf = (void *)jlong_to_ptr(address);
81 
82     return convertReturnVal(env, pread64(fd, buf, len, offset), JNI_TRUE);
83 }
84 
85 JNIEXPORT jlong JNICALL
FileDispatcherImpl_readv0(JNIEnv * env,jclass clazz,jobject fdo,jlong address,jint len)86 FileDispatcherImpl_readv0(JNIEnv *env, jclass clazz,
87                               jobject fdo, jlong address, jint len)
88 {
89     jint fd = fdval(env, fdo);
90     struct iovec *iov = (struct iovec *)jlong_to_ptr(address);
91     return convertLongReturnVal(env, readv(fd, iov, len), JNI_TRUE);
92 }
93 
94 JNIEXPORT jint JNICALL
FileDispatcherImpl_write0(JNIEnv * env,jclass clazz,jobject fdo,jlong address,jint len)95 FileDispatcherImpl_write0(JNIEnv *env, jclass clazz,
96                               jobject fdo, jlong address, jint len)
97 {
98     jint fd = fdval(env, fdo);
99     void *buf = (void *)jlong_to_ptr(address);
100 
101     return convertReturnVal(env, write(fd, buf, len), JNI_FALSE);
102 }
103 
104 JNIEXPORT jint JNICALL
FileDispatcherImpl_pwrite0(JNIEnv * env,jclass clazz,jobject fdo,jlong address,jint len,jlong offset)105 FileDispatcherImpl_pwrite0(JNIEnv *env, jclass clazz, jobject fdo,
106                             jlong address, jint len, jlong offset)
107 {
108     jint fd = fdval(env, fdo);
109     void *buf = (void *)jlong_to_ptr(address);
110 
111     return convertReturnVal(env, pwrite64(fd, buf, len, offset), JNI_FALSE);
112 }
113 
114 JNIEXPORT jlong JNICALL
FileDispatcherImpl_writev0(JNIEnv * env,jclass clazz,jobject fdo,jlong address,jint len)115 FileDispatcherImpl_writev0(JNIEnv *env, jclass clazz,
116                                        jobject fdo, jlong address, jint len)
117 {
118     jint fd = fdval(env, fdo);
119     struct iovec *iov = (struct iovec *)jlong_to_ptr(address);
120     return convertLongReturnVal(env, writev(fd, iov, len), JNI_FALSE);
121 }
122 
123 static jlong
handle(JNIEnv * env,jlong rv,char * msg)124 handle(JNIEnv *env, jlong rv, char *msg)
125 {
126     if (rv >= 0)
127         return rv;
128     if (errno == EINTR)
129         return IOS_INTERRUPTED;
130     JNU_ThrowIOExceptionWithLastError(env, msg);
131     return IOS_THROWN;
132 }
133 
134 JNIEXPORT jint JNICALL
FileDispatcherImpl_force0(JNIEnv * env,jobject this,jobject fdo,jboolean md)135 FileDispatcherImpl_force0(JNIEnv *env, jobject this,
136                                           jobject fdo, jboolean md)
137 {
138     jint fd = fdval(env, fdo);
139     int result = 0;
140 
141     if (md == JNI_FALSE) {
142         result = fdatasync(fd);
143     } else {
144 #ifdef _AIX
145         /* On AIX, calling fsync on a file descriptor that is opened only for
146          * reading results in an error ("EBADF: The FileDescriptor parameter is
147          * not a valid file descriptor open for writing.").
148          * However, at this point it is not possibly anymore to read the
149          * 'writable' attribute of the corresponding file channel so we have to
150          * use 'fcntl'.
151          */
152         int getfl = fcntl(fd, F_GETFL);
153         if (getfl >= 0 && (getfl & O_ACCMODE) == O_RDONLY) {
154             return 0;
155         }
156 #endif
157         result = fsync(fd);
158     }
159     return handle(env, result, "Force failed");
160 }
161 
162 JNIEXPORT jint JNICALL
FileDispatcherImpl_truncate0(JNIEnv * env,jobject this,jobject fdo,jlong size)163 FileDispatcherImpl_truncate0(JNIEnv *env, jobject this,
164                                              jobject fdo, jlong size)
165 {
166     return handle(env,
167                   ftruncate64(fdval(env, fdo), size),
168                   "Truncation failed");
169 }
170 
171 JNIEXPORT jlong JNICALL
FileDispatcherImpl_size0(JNIEnv * env,jobject this,jobject fdo)172 FileDispatcherImpl_size0(JNIEnv *env, jobject this, jobject fdo)
173 {
174     jint fd = fdval(env, fdo);
175     struct stat64 fbuf;
176 
177     if (fstat64(fd, &fbuf) < 0)
178         return handle(env, -1, "Size failed");
179 
180 #ifdef BLKGETSIZE64
181     if (S_ISBLK(fbuf.st_mode)) {
182         uint64_t size;
183         if (ioctl(fd, BLKGETSIZE64, &size) < 0)
184             return handle(env, -1, "Size failed");
185         return (jlong)size;
186     }
187 #endif
188 
189     return fbuf.st_size;
190 }
191 
192 JNIEXPORT jint JNICALL
FileDispatcherImpl_lock0(JNIEnv * env,jobject this,jobject fdo,jboolean block,jlong pos,jlong size,jboolean shared)193 FileDispatcherImpl_lock0(JNIEnv *env, jobject this, jobject fdo,
194                                       jboolean block, jlong pos, jlong size,
195                                       jboolean shared)
196 {
197     jint fd = fdval(env, fdo);
198     jint lockResult = 0;
199     int cmd = 0;
200     struct flock64 fl;
201 
202     fl.l_whence = SEEK_SET;
203     if (size == (jlong)java_lang_Long_MAX_VALUE) {
204         fl.l_len = (off64_t)0;
205     } else {
206         fl.l_len = (off64_t)size;
207     }
208     fl.l_start = (off64_t)pos;
209     if (shared == JNI_TRUE) {
210         fl.l_type = F_RDLCK;
211     } else {
212         fl.l_type = F_WRLCK;
213     }
214     if (block == JNI_TRUE) {
215         cmd = F_SETLKW64;
216     } else {
217         cmd = F_SETLK64;
218     }
219     lockResult = fcntl(fd, cmd, &fl);
220     if (lockResult < 0) {
221         if ((cmd == F_SETLK64) && (errno == EAGAIN || errno == EACCES))
222             return sun_nio_ch_FileDispatcherImpl_NO_LOCK;
223         if (errno == EINTR)
224             return sun_nio_ch_FileDispatcherImpl_INTERRUPTED;
225         JNU_ThrowIOExceptionWithLastError(env, "Lock failed");
226     }
227     return 0;
228 }
229 
230 JNIEXPORT void JNICALL
FileDispatcherImpl_release0(JNIEnv * env,jobject this,jobject fdo,jlong pos,jlong size)231 FileDispatcherImpl_release0(JNIEnv *env, jobject this,
232                                          jobject fdo, jlong pos, jlong size)
233 {
234     jint fd = fdval(env, fdo);
235     jint lockResult = 0;
236     struct flock64 fl;
237     int cmd = F_SETLK64;
238 
239     fl.l_whence = SEEK_SET;
240     if (size == (jlong)java_lang_Long_MAX_VALUE) {
241         fl.l_len = (off64_t)0;
242     } else {
243         fl.l_len = (off64_t)size;
244     }
245     fl.l_start = (off64_t)pos;
246     fl.l_type = F_UNLCK;
247     lockResult = fcntl(fd, cmd, &fl);
248     if (lockResult < 0) {
249         JNU_ThrowIOExceptionWithLastError(env, "Release failed");
250     }
251 }
252 
253 
closeFileDescriptor(JNIEnv * env,int fd)254 static void closeFileDescriptor(JNIEnv *env, int fd) {
255     if (fd != -1) {
256         int result = close(fd);
257         if (result < 0)
258             JNU_ThrowIOExceptionWithLastError(env, "Close failed");
259     }
260 }
261 
262 JNIEXPORT void JNICALL
FileDispatcherImpl_close0(JNIEnv * env,jclass clazz,jobject fdo)263 FileDispatcherImpl_close0(JNIEnv *env, jclass clazz, jobject fdo)
264 {
265     jint fd = fdval(env, fdo);
266     closeFileDescriptor(env, fd);
267 }
268 
269 JNIEXPORT void JNICALL
FileDispatcherImpl_preClose0(JNIEnv * env,jclass clazz,jobject fdo)270 FileDispatcherImpl_preClose0(JNIEnv *env, jclass clazz, jobject fdo)
271 {
272     jint fd = fdval(env, fdo);
273     int preCloseFD = open("/dev/null", O_RDWR | O_CLOEXEC);
274     if (preCloseFD < 0) {
275         JNU_ThrowIOExceptionWithLastError(env, "open(\"/dev/null\") failed");
276         return;
277     }
278     if (dup2(preCloseFD, fd) < 0) {
279         JNU_ThrowIOExceptionWithLastError(env, "dup2 failed");
280     }
281     close(preCloseFD);
282 }
283 
284 JNIEXPORT void JNICALL
FileDispatcherImpl_closeIntFD(JNIEnv * env,jclass clazz,jint fd)285 FileDispatcherImpl_closeIntFD(JNIEnv *env, jclass clazz, jint fd)
286 {
287     closeFileDescriptor(env, fd);
288 }
289 
290 static JNINativeMethod gMethods[] = {
291   NATIVE_METHOD(FileDispatcherImpl, closeIntFD, "(I)V"),
292   NATIVE_METHOD(FileDispatcherImpl, preClose0, "(Ljava/io/FileDescriptor;)V"),
293   NATIVE_METHOD(FileDispatcherImpl, close0, "(Ljava/io/FileDescriptor;)V"),
294   NATIVE_METHOD(FileDispatcherImpl, release0, "(Ljava/io/FileDescriptor;JJ)V"),
295   NATIVE_METHOD(FileDispatcherImpl, lock0, "(Ljava/io/FileDescriptor;ZJJZ)I"),
296   NATIVE_METHOD(FileDispatcherImpl, size0, "(Ljava/io/FileDescriptor;)J"),
297   NATIVE_METHOD(FileDispatcherImpl, truncate0, "(Ljava/io/FileDescriptor;J)I"),
298   NATIVE_METHOD(FileDispatcherImpl, force0, "(Ljava/io/FileDescriptor;Z)I"),
299   NATIVE_METHOD(FileDispatcherImpl, writev0, "(Ljava/io/FileDescriptor;JI)J"),
300   NATIVE_METHOD(FileDispatcherImpl, pwrite0, "(Ljava/io/FileDescriptor;JIJ)I"),
301   NATIVE_METHOD(FileDispatcherImpl, write0, "(Ljava/io/FileDescriptor;JI)I"),
302   NATIVE_METHOD(FileDispatcherImpl, readv0, "(Ljava/io/FileDescriptor;JI)J"),
303   NATIVE_METHOD(FileDispatcherImpl, pread0, "(Ljava/io/FileDescriptor;JIJ)I"),
304   NATIVE_METHOD(FileDispatcherImpl, read0, "(Ljava/io/FileDescriptor;JI)I"),
305 };
306 
register_sun_nio_ch_FileDispatcherImpl(JNIEnv * env)307 void register_sun_nio_ch_FileDispatcherImpl(JNIEnv* env) {
308   jniRegisterNativeMethods(env, "sun/nio/ch/FileDispatcherImpl", gMethods, NELEM(gMethods));
309 }
310