1 /*
2  * Copyright (c) 2002, 2006, 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 "jni.h"
29 #include "jni_util.h"
30 #include "jvm.h"
31 #include "jlong.h"
32 #include "nio_util.h"
33 #include <nativehelper/JNIHelp.h>
34 
35 #ifdef __linux__
36   #include <pthread.h>
37   #include <sys/signal.h>
38   // Android-changed: Bionic (and AsynchronousCloseMonitor) expects libcore to use
39   // __SIGRTMIN + 2, not __SIGRTMAX - 2
40   /* Also defined in net/linux_close.c */
41   #define INTERRUPT_SIGNAL (__SIGRTMIN + 2)
42 #elif __solaris__
43   #include <thread.h>
44   #include <signal.h>
45   #define INTERRUPT_SIGNAL (SIGRTMAX - 2)
46 #elif _ALLBSD_SOURCE
47   #include <pthread.h>
48   #include <signal.h>
49   /* Also defined in net/bsd_close.c */
50   #define INTERRUPT_SIGNAL SIGIO
51 // BEGIN Android-added: Fuchsia: Support for Fuchsia platform.
52 #elif __Fuchsia__
53   #include <pthread.h>
54   #include <signal.h>
55   /* Also defined in net/bsd_close.c */
56   #define INTERRUPT_SIGNAL SIGIO
57 // END Android-added: Fuchsia: Support for Fuchsia platform.
58 #else
59   #error "missing platform-specific definition here"
60 #endif
61 
62 #define NATIVE_METHOD(className, functionName, signature) \
63 { #functionName, signature, (void*)(className ## _ ## functionName) }
64 
65 static void
nullHandler(int sig)66 nullHandler(int sig)
67 {
68 }
69 
NativeThread_init(JNIEnv * env)70 static void  NativeThread_init(JNIEnv *env)
71 {
72     /* Install the null handler for INTERRUPT_SIGNAL.  This might overwrite the
73      * handler previously installed by java/net/linux_close.c, but that's okay
74      * since neither handler actually does anything.  We install our own
75      * handler here simply out of paranoia; ultimately the two mechanisms
76      * should somehow be unified, perhaps within the VM.
77      */
78 
79     sigset_t ss;
80     struct sigaction sa, osa;
81     sa.sa_handler = nullHandler;
82     sa.sa_flags = 0;
83     sigemptyset(&sa.sa_mask);
84     if (sigaction(INTERRUPT_SIGNAL, &sa, &osa) < 0)
85         JNU_ThrowIOExceptionWithLastError(env, "sigaction");
86 }
87 
88 JNIEXPORT jlong JNICALL
NativeThread_current(JNIEnv * env,jclass cl)89 NativeThread_current(JNIEnv *env, jclass cl)
90 {
91 #ifdef __solaris__
92     return (jlong)thr_self();
93 #else
94     return (jlong)pthread_self();
95 #endif
96 }
97 
98 JNIEXPORT void JNICALL
NativeThread_signal(JNIEnv * env,jclass cl,jlong thread)99 NativeThread_signal(JNIEnv *env, jclass cl, jlong thread)
100 {
101     int ret;
102 #ifdef __solaris__
103     ret = thr_kill((thread_t)thread, INTERRUPT_SIGNAL);
104 #else
105     ret = pthread_kill((pthread_t)thread, INTERRUPT_SIGNAL);
106 #endif
107     if (ret != 0)
108         JNU_ThrowIOExceptionWithLastError(env, "Thread signal failed");
109 }
110 
111 static JNINativeMethod gMethods[] = {
112   NATIVE_METHOD(NativeThread, current, "()J"),
113   NATIVE_METHOD(NativeThread, signal, "(J)V"),
114 };
115 
register_sun_nio_ch_NativeThread(JNIEnv * env)116 void register_sun_nio_ch_NativeThread(JNIEnv* env) {
117   jniRegisterNativeMethods(env, "sun/nio/ch/NativeThread", gMethods, NELEM(gMethods));
118   NativeThread_init(env);
119 }
120