1 /*
2  * Copyright (c) 2008, 2011, 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 
31 #include <stdlib.h>
32 #include <dlfcn.h>
33 #include <sys/types.h>
34 #include <sys/socket.h>
35 // Android-changed: Point to correct location of header. http://b/119426171
36 // #include <sys/poll.h>
37 #include <poll.h>
38 #if !defined(__Fuchsia__)
39 #include <sys/inotify.h>
40 #endif
41 
42 #include "sun_nio_fs_LinuxWatchService.h"
43 
throwUnixException(JNIEnv * env,int errnum)44 static void throwUnixException(JNIEnv* env, int errnum) {
45     jobject x = JNU_NewObjectByName(env, "sun/nio/fs/UnixException",
46         "(I)V", errnum);
47     if (x != NULL) {
48         (*env)->Throw(env, x);
49     }
50 }
51 
52 JNIEXPORT jint JNICALL
Java_sun_nio_fs_LinuxWatchService_eventSize(JNIEnv * env,jclass clazz)53 Java_sun_nio_fs_LinuxWatchService_eventSize(JNIEnv *env, jclass clazz)
54 {
55     return (jint)sizeof(struct inotify_event);
56 }
57 
58 JNIEXPORT jintArray JNICALL
Java_sun_nio_fs_LinuxWatchService_eventOffsets(JNIEnv * env,jclass clazz)59 Java_sun_nio_fs_LinuxWatchService_eventOffsets(JNIEnv *env, jclass clazz)
60 {
61     jintArray result = (*env)->NewIntArray(env, 5);
62     if (result != NULL) {
63         jint arr[5];
64         arr[0] = (jint)offsetof(struct inotify_event, wd);
65         arr[1] = (jint)offsetof(struct inotify_event, mask);
66         arr[2] = (jint)offsetof(struct inotify_event, cookie);
67         arr[3] = (jint)offsetof(struct inotify_event, len);
68         arr[4] = (jint)offsetof(struct inotify_event, name);
69         (*env)->SetIntArrayRegion(env, result, 0, 5, arr);
70     }
71     return result;
72 }
73 
74 
75 JNIEXPORT jint JNICALL
Java_sun_nio_fs_LinuxWatchService_inotifyInit(JNIEnv * env,jclass clazz)76 Java_sun_nio_fs_LinuxWatchService_inotifyInit
77     (JNIEnv* env, jclass clazz)
78 {
79     int ifd = inotify_init();
80     if (ifd == -1) {
81         throwUnixException(env, errno);
82     }
83     return (jint)ifd;
84 }
85 
86 JNIEXPORT jint JNICALL
Java_sun_nio_fs_LinuxWatchService_inotifyAddWatch(JNIEnv * env,jclass clazz,jint fd,jlong address,jint mask)87 Java_sun_nio_fs_LinuxWatchService_inotifyAddWatch
88     (JNIEnv* env, jclass clazz, jint fd, jlong address, jint mask)
89 {
90     int wfd = -1;
91     const char* path = (const char*)jlong_to_ptr(address);
92 
93     wfd = inotify_add_watch((int)fd, path, mask);
94     if (wfd == -1) {
95         throwUnixException(env, errno);
96     }
97     return (jint)wfd;
98 }
99 
100 JNIEXPORT void JNICALL
Java_sun_nio_fs_LinuxWatchService_inotifyRmWatch(JNIEnv * env,jclass clazz,jint fd,jint wd)101 Java_sun_nio_fs_LinuxWatchService_inotifyRmWatch
102     (JNIEnv* env, jclass clazz, jint fd, jint wd)
103 {
104     int err = inotify_rm_watch((int)fd, (int)wd);
105     if (err == -1)
106         throwUnixException(env, errno);
107 }
108 
109 JNIEXPORT void JNICALL
Java_sun_nio_fs_LinuxWatchService_configureBlocking(JNIEnv * env,jclass clazz,jint fd,jboolean blocking)110 Java_sun_nio_fs_LinuxWatchService_configureBlocking
111     (JNIEnv* env, jclass clazz, jint fd, jboolean blocking)
112 {
113     int flags = fcntl(fd, F_GETFL);
114 
115     if ((blocking == JNI_FALSE) && !(flags & O_NONBLOCK))
116         fcntl(fd, F_SETFL, flags | O_NONBLOCK);
117     else if ((blocking == JNI_TRUE) && (flags & O_NONBLOCK))
118         fcntl(fd, F_SETFL, flags & ~O_NONBLOCK);
119 }
120 
121 JNIEXPORT void JNICALL
Java_sun_nio_fs_LinuxWatchService_socketpair(JNIEnv * env,jclass clazz,jintArray sv)122 Java_sun_nio_fs_LinuxWatchService_socketpair
123     (JNIEnv* env, jclass clazz, jintArray sv)
124 {
125     int sp[2];
126     if (socketpair(PF_UNIX, SOCK_STREAM, 0, sp) == -1) {
127         throwUnixException(env, errno);
128     } else {
129         jint res[2];
130         res[0] = (jint)sp[0];
131         res[1] = (jint)sp[1];
132         (*env)->SetIntArrayRegion(env, sv, 0, 2, &res[0]);
133     }
134 }
135 
136 JNIEXPORT jint JNICALL
Java_sun_nio_fs_LinuxWatchService_poll(JNIEnv * env,jclass clazz,jint fd1,jint fd2)137 Java_sun_nio_fs_LinuxWatchService_poll
138     (JNIEnv* env, jclass clazz, jint fd1, jint fd2)
139 {
140     struct pollfd ufds[2];
141     int n;
142 
143     ufds[0].fd = fd1;
144     ufds[0].events = POLLIN;
145     ufds[1].fd = fd2;
146     ufds[1].events = POLLIN;
147 
148     n = poll(&ufds[0], 2, -1);
149     if (n == -1) {
150         if (errno == EINTR) {
151             n = 0;
152         } else {
153             throwUnixException(env, errno);
154         }
155      }
156     return (jint)n;
157 }
158