1 /*
2 * Copyright (c) 2000, 2017, 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 #include <sys/statvfs.h>
38 #if defined(__linux__)
39 #include <linux/fs.h>
40 #include <sys/ioctl.h>
41 #endif
42 #include "nio.h"
43 #include "nio_util.h"
44
45 #ifdef _ALLBSD_SOURCE
46 #define stat64 stat
47 #define flock64 flock
48 #define off64_t off_t
49 #define F_SETLKW64 F_SETLKW
50 #define F_SETLK64 F_SETLK
51
52 #define pread64 pread
53 #define pwrite64 pwrite
54 #define ftruncate64 ftruncate
55 #define fstat64 fstat
56
57 #define fdatasync fsync
58 #endif
59
60 static int preCloseFD = -1; /* File descriptor to which we dup other fd's
61 before closing them for real */
62
63
64 JNIEXPORT void JNICALL
65 Java_sun_nio_ch_FileDispatcherImpl_init(JNIEnv *env, jclass cl)
66 {
67 int sp[2];
68 if (socketpair(PF_UNIX, SOCK_STREAM, 0, sp) < 0) {
69 JNU_ThrowIOExceptionWithLastError(env, "socketpair failed");
70 return;
71 }
72 preCloseFD = sp[0];
73 close(sp[1]);
74 }
75
76 JNIEXPORT jint JNICALL
77 Java_sun_nio_ch_FileDispatcherImpl_read0(JNIEnv *env, jclass clazz,
78 jobject fdo, jlong address, jint len)
79 {
80 jint fd = fdval(env, fdo);
81 void *buf = (void *)jlong_to_ptr(address);
82
83 return convertReturnVal(env, read(fd, buf, len), JNI_TRUE);
84 }
85
86 JNIEXPORT jint JNICALL
87 Java_sun_nio_ch_FileDispatcherImpl_pread0(JNIEnv *env, jclass clazz, jobject fdo,
88 jlong address, jint len, jlong offset)
89 {
90 jint fd = fdval(env, fdo);
91 void *buf = (void *)jlong_to_ptr(address);
92
93 return convertReturnVal(env, pread64(fd, buf, len, offset), JNI_TRUE);
94 }
95
96 JNIEXPORT jlong JNICALL
97 Java_sun_nio_ch_FileDispatcherImpl_readv0(JNIEnv *env, jclass clazz,
98 jobject fdo, jlong address, jint len)
99 {
100 jint fd = fdval(env, fdo);
101 struct iovec *iov = (struct iovec *)jlong_to_ptr(address);
102 return convertLongReturnVal(env, readv(fd, iov, len), JNI_TRUE);
103 }
104
105 JNIEXPORT jint JNICALL
106 Java_sun_nio_ch_FileDispatcherImpl_write0(JNIEnv *env, jclass clazz,
107 jobject fdo, jlong address, jint len)
108 {
109 jint fd = fdval(env, fdo);
110 void *buf = (void *)jlong_to_ptr(address);
111
112 return convertReturnVal(env, write(fd, buf, len), JNI_FALSE);
113 }
114
115 JNIEXPORT jint JNICALL
116 Java_sun_nio_ch_FileDispatcherImpl_pwrite0(JNIEnv *env, jclass clazz, jobject fdo,
117 jlong address, jint len, jlong offset)
118 {
119 jint fd = fdval(env, fdo);
120 void *buf = (void *)jlong_to_ptr(address);
121
122 return convertReturnVal(env, pwrite64(fd, buf, len, offset), JNI_FALSE);
123 }
124
125 JNIEXPORT jlong JNICALL
126 Java_sun_nio_ch_FileDispatcherImpl_writev0(JNIEnv *env, jclass clazz,
127 jobject fdo, jlong address, jint len)
128 {
129 jint fd = fdval(env, fdo);
130 struct iovec *iov = (struct iovec *)jlong_to_ptr(address);
131 return convertLongReturnVal(env, writev(fd, iov, len), JNI_FALSE);
132 }
133
134 static jlong
135 handle(JNIEnv *env, jlong rv, char *msg)
136 {
137 if (rv >= 0)
138 return rv;
139 if (errno == EINTR)
140 return IOS_INTERRUPTED;
141 JNU_ThrowIOExceptionWithLastError(env, msg);
142 return IOS_THROWN;
143 }
144
145 JNIEXPORT jint JNICALL
146 Java_sun_nio_ch_FileDispatcherImpl_force0(JNIEnv *env, jobject this,
147 jobject fdo, jboolean md)
148 {
149 jint fd = fdval(env, fdo);
150 int result = 0;
151
152 #ifdef MACOSX
153 result = fcntl(fd, F_FULLFSYNC);
154 if (result == -1 && errno == ENOTSUP) {
155 /* Try fsync() in case F_FULLSYUNC is not implemented on the file system. */
156 result = fsync(fd);
157 }
158 #else /* end MACOSX, begin not-MACOSX */
159 if (md == JNI_FALSE) {
160 result = fdatasync(fd);
161 } else {
162 #ifdef _AIX
163 /* On AIX, calling fsync on a file descriptor that is opened only for
164 * reading results in an error ("EBADF: The FileDescriptor parameter is
165 * not a valid file descriptor open for writing.").
166 * However, at this point it is not possibly anymore to read the
167 * 'writable' attribute of the corresponding file channel so we have to
168 * use 'fcntl'.
169 */
170 int getfl = fcntl(fd, F_GETFL);
171 if (getfl >= 0 && (getfl & O_ACCMODE) == O_RDONLY) {
172 return 0;
173 }
174 #endif /* _AIX */
175 result = fsync(fd);
176 }
177 #endif /* not-MACOSX */
178 return handle(env, result, "Force failed");
179 }
180
181 JNIEXPORT jint JNICALL
182 Java_sun_nio_ch_FileDispatcherImpl_truncate0(JNIEnv *env, jobject this,
183 jobject fdo, jlong size)
184 {
185 return handle(env,
186 ftruncate64(fdval(env, fdo), size),
187 "Truncation failed");
188 }
189
190 JNIEXPORT jint JNICALL
191 Java_sun_nio_ch_FileDispatcherImpl_allocate0(JNIEnv *env, jobject this,
192 jobject fdo, jlong size)
193 {
194 #if defined(__linux__)
195 /*
196 * On Linux, if the file size is being increased, then ftruncate64()
197 * will modify the metadata value of the size without actually allocating
198 * any blocks which can cause a SIGBUS error if the file is subsequently
199 * memory-mapped.
200 */
201 // Return on success or if errno is neither EOPNOTSUPP nor ENOSYS
202 int result = fallocate64(fdval(env, fdo), 0, 0, size);
203 if (result == 0) {
204 return 0;
205 } else if (errno != EOPNOTSUPP && errno != ENOSYS) {
206 return handle(env, result, "Allocation failed");
207 }
208 #endif
209 return handle(env,
210 ftruncate64(fdval(env, fdo), size),
211 "Truncation failed");
212 }
213
214 JNIEXPORT jlong JNICALL
215 Java_sun_nio_ch_FileDispatcherImpl_size0(JNIEnv *env, jobject this, jobject fdo)
216 {
217 jint fd = fdval(env, fdo);
218 struct stat64 fbuf;
219
220 if (fstat64(fd, &fbuf) < 0)
221 return handle(env, -1, "Size failed");
222
223 #ifdef BLKGETSIZE64
224 if (S_ISBLK(fbuf.st_mode)) {
225 uint64_t size;
226 if (ioctl(fd, BLKGETSIZE64, &size) < 0)
227 return handle(env, -1, "Size failed");
228 return (jlong)size;
229 }
230 #endif
231
232 return fbuf.st_size;
233 }
234
235 JNIEXPORT jint JNICALL
236 Java_sun_nio_ch_FileDispatcherImpl_lock0(JNIEnv *env, jobject this, jobject fdo,
237 jboolean block, jlong pos, jlong size,
238 jboolean shared)
239 {
240 jint fd = fdval(env, fdo);
241 jint lockResult = 0;
242 int cmd = 0;
243 struct flock64 fl;
244
245 fl.l_whence = SEEK_SET;
246 if (size == (jlong)java_lang_Long_MAX_VALUE) {
247 fl.l_len = (off64_t)0;
248 } else {
249 fl.l_len = (off64_t)size;
250 }
251 fl.l_start = (off64_t)pos;
252 if (shared == JNI_TRUE) {
253 fl.l_type = F_RDLCK;
254 } else {
255 fl.l_type = F_WRLCK;
256 }
257 if (block == JNI_TRUE) {
258 cmd = F_SETLKW64;
259 } else {
260 cmd = F_SETLK64;
261 }
262 lockResult = fcntl(fd, cmd, &fl);
263 if (lockResult < 0) {
264 if ((cmd == F_SETLK64) && (errno == EAGAIN || errno == EACCES))
265 return sun_nio_ch_FileDispatcherImpl_NO_LOCK;
266 if (errno == EINTR)
267 return sun_nio_ch_FileDispatcherImpl_INTERRUPTED;
268 JNU_ThrowIOExceptionWithLastError(env, "Lock failed");
269 }
270 return 0;
271 }
272
273 JNIEXPORT void JNICALL
274 Java_sun_nio_ch_FileDispatcherImpl_release0(JNIEnv *env, jobject this,
275 jobject fdo, jlong pos, jlong size)
276 {
277 jint fd = fdval(env, fdo);
278 jint lockResult = 0;
279 struct flock64 fl;
280 int cmd = F_SETLK64;
281
282 fl.l_whence = SEEK_SET;
283 if (size == (jlong)java_lang_Long_MAX_VALUE) {
284 fl.l_len = (off64_t)0;
285 } else {
286 fl.l_len = (off64_t)size;
287 }
288 fl.l_start = (off64_t)pos;
289 fl.l_type = F_UNLCK;
290 lockResult = fcntl(fd, cmd, &fl);
291 if (lockResult < 0) {
292 JNU_ThrowIOExceptionWithLastError(env, "Release failed");
293 }
294 }
295
296
297 static void closeFileDescriptor(JNIEnv *env, int fd) {
298 if (fd != -1) {
299 int result = close(fd);
300 if (result < 0)
301 JNU_ThrowIOExceptionWithLastError(env, "Close failed");
302 }
303 }
304
305 JNIEXPORT void JNICALL
306 Java_sun_nio_ch_FileDispatcherImpl_close0(JNIEnv *env, jclass clazz, jobject fdo)
307 {
308 jint fd = fdval(env, fdo);
309 closeFileDescriptor(env, fd);
310 }
311
312 JNIEXPORT void JNICALL
313 Java_sun_nio_ch_FileDispatcherImpl_preClose0(JNIEnv *env, jclass clazz, jobject fdo)
314 {
315 jint fd = fdval(env, fdo);
316 if (preCloseFD >= 0) {
317 if (dup2(preCloseFD, fd) < 0)
318 JNU_ThrowIOExceptionWithLastError(env, "dup2 failed");
319 }
320 }
321
322 JNIEXPORT void JNICALL
323 Java_sun_nio_ch_FileDispatcherImpl_closeIntFD(JNIEnv *env, jclass clazz, jint fd)
324 {
325 closeFileDescriptor(env, fd);
326 }
327
328 JNIEXPORT jint JNICALL
329 Java_sun_nio_ch_FileDispatcherImpl_setDirect0(JNIEnv *env, jclass clazz,
330 jobject fdo)
331 {
332 jint fd = fdval(env, fdo);
333 jint result;
334 #ifdef MACOSX
335 struct statvfs file_stat;
336 #else
337 struct statvfs64 file_stat;
338 #endif
339
340 #if defined(O_DIRECT) || defined(F_NOCACHE) || defined(DIRECTIO_ON)
341 #ifdef O_DIRECT
342 jint orig_flag;
343 orig_flag = fcntl(fd, F_GETFL);
344 if (orig_flag == -1) {
345 JNU_ThrowIOExceptionWithLastError(env, "DirectIO setup failed");
346 return -1;
347 }
348 result = fcntl(fd, F_SETFL, orig_flag | O_DIRECT);
349 if (result == -1) {
350 JNU_ThrowIOExceptionWithLastError(env, "DirectIO setup failed");
351 return result;
352 }
353 #elif F_NOCACHE
354 result = fcntl(fd, F_NOCACHE, 1);
355 if (result == -1) {
356 JNU_ThrowIOExceptionWithLastError(env, "DirectIO setup failed");
357 return result;
358 }
359 #elif DIRECTIO_ON
360 result = directio(fd, DIRECTIO_ON);
361 if (result == -1) {
362 JNU_ThrowIOExceptionWithLastError(env, "DirectIO setup failed");
363 return result;
364 }
365 #endif
366 #ifdef MACOSX
367 result = fstatvfs(fd, &file_stat);
368 #else
369 result = fstatvfs64(fd, &file_stat);
370 #endif
371 if(result == -1) {
372 JNU_ThrowIOExceptionWithLastError(env, "DirectIO setup failed");
373 return result;
374 } else {
375 result = (int)file_stat.f_frsize;
376 }
377 #else
378 result == -1;
379 #endif
380 return result;
381 }