| /* |
| * Copyright (c) 1999, 2011, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| * |
| */ |
| |
| #include "precompiled.hpp" |
| #include "prims/jvm.h" |
| #include "runtime/interfaceSupport.hpp" |
| #include "runtime/osThread.hpp" |
| |
| #include <signal.h> |
| |
| |
| // sun.misc.Signal /////////////////////////////////////////////////////////// |
| // Signal code is mostly copied from classic vm, signals_md.c 1.4 98/08/23 |
| /* |
| * This function is included primarily as a debugging aid. If Java is |
| * running in a console window, then pressing <CTRL-\\> will cause |
| * the current state of all active threads and monitors to be written |
| * to the console window. |
| */ |
| |
| JVM_ENTRY_NO_ENV(void*, JVM_RegisterSignal(jint sig, void* handler)) |
| // Copied from classic vm |
| // signals_md.c 1.4 98/08/23 |
| void* newHandler = handler == (void *)2 |
| ? os::user_handler() |
| : handler; |
| switch (sig) { |
| /* The following are already used by the VM. */ |
| case INTERRUPT_SIGNAL: |
| case SIGFPE: |
| case SIGILL: |
| case SIGSEGV: |
| |
| /* The following signal is used by the VM to dump thread stacks unless |
| ReduceSignalUsage is set, in which case the user is allowed to set |
| his own _native_ handler for this signal; thus, in either case, |
| we do not allow JVM_RegisterSignal to change the handler. */ |
| case BREAK_SIGNAL: |
| return (void *)-1; |
| |
| /* The following signals are used for Shutdown Hooks support. However, if |
| ReduceSignalUsage (-Xrs) is set, Shutdown Hooks must be invoked via |
| System.exit(), Java is not allowed to use these signals, and the the |
| user is allowed to set his own _native_ handler for these signals and |
| invoke System.exit() as needed. Terminator.setup() is avoiding |
| registration of these signals when -Xrs is present. |
| - If the HUP signal is ignored (from the nohup) command, then Java |
| is not allowed to use this signal. |
| */ |
| |
| case SHUTDOWN1_SIGNAL: |
| case SHUTDOWN2_SIGNAL: |
| case SHUTDOWN3_SIGNAL: |
| if (ReduceSignalUsage) return (void*)-1; |
| if (os::Linux::is_sig_ignored(sig)) return (void*)1; |
| } |
| |
| void* oldHandler = os::signal(sig, newHandler); |
| if (oldHandler == os::user_handler()) { |
| return (void *)2; |
| } else { |
| return oldHandler; |
| } |
| JVM_END |
| |
| |
| JVM_ENTRY_NO_ENV(jboolean, JVM_RaiseSignal(jint sig)) |
| if (ReduceSignalUsage) { |
| // do not allow SHUTDOWN1_SIGNAL,SHUTDOWN2_SIGNAL,SHUTDOWN3_SIGNAL, |
| // BREAK_SIGNAL to be raised when ReduceSignalUsage is set, since |
| // no handler for them is actually registered in JVM or via |
| // JVM_RegisterSignal. |
| if (sig == SHUTDOWN1_SIGNAL || sig == SHUTDOWN2_SIGNAL || |
| sig == SHUTDOWN3_SIGNAL || sig == BREAK_SIGNAL) { |
| return JNI_FALSE; |
| } |
| } |
| else if ((sig == SHUTDOWN1_SIGNAL || sig == SHUTDOWN2_SIGNAL || |
| sig == SHUTDOWN3_SIGNAL) && os::Linux::is_sig_ignored(sig)) { |
| // do not allow SHUTDOWN1_SIGNAL to be raised when SHUTDOWN1_SIGNAL |
| // is ignored, since no handler for them is actually registered in JVM |
| // or via JVM_RegisterSignal. |
| // This also applies for SHUTDOWN2_SIGNAL and SHUTDOWN3_SIGNAL |
| return JNI_FALSE; |
| } |
| |
| os::signal_raise(sig); |
| return JNI_TRUE; |
| JVM_END |
| |
| /* |
| All the defined signal names for Linux. |
| |
| NOTE that not all of these names are accepted by our Java implementation |
| |
| Via an existing claim by the VM, sigaction restrictions, or |
| the "rules of Unix" some of these names will be rejected at runtime. |
| For example the VM sets up to handle USR1, sigaction returns EINVAL for |
| STOP, and Linux simply doesn't allow catching of KILL. |
| |
| Here are the names currently accepted by a user of sun.misc.Signal with |
| 1.4.1 (ignoring potential interaction with use of chaining, etc): |
| |
| HUP, INT, TRAP, ABRT, IOT, BUS, USR2, PIPE, ALRM, TERM, STKFLT, |
| CLD, CHLD, CONT, TSTP, TTIN, TTOU, URG, XCPU, XFSZ, VTALRM, PROF, |
| WINCH, POLL, IO, PWR, SYS |
| |
| */ |
| |
| struct siglabel { |
| const char *name; |
| int number; |
| }; |
| |
| struct siglabel siglabels[] = { |
| /* derived from /usr/include/bits/signum.h on RH7.2 */ |
| "HUP", SIGHUP, /* Hangup (POSIX). */ |
| "INT", SIGINT, /* Interrupt (ANSI). */ |
| "QUIT", SIGQUIT, /* Quit (POSIX). */ |
| "ILL", SIGILL, /* Illegal instruction (ANSI). */ |
| "TRAP", SIGTRAP, /* Trace trap (POSIX). */ |
| "ABRT", SIGABRT, /* Abort (ANSI). */ |
| "IOT", SIGIOT, /* IOT trap (4.2 BSD). */ |
| "BUS", SIGBUS, /* BUS error (4.2 BSD). */ |
| "FPE", SIGFPE, /* Floating-point exception (ANSI). */ |
| "KILL", SIGKILL, /* Kill, unblockable (POSIX). */ |
| "USR1", SIGUSR1, /* User-defined signal 1 (POSIX). */ |
| "SEGV", SIGSEGV, /* Segmentation violation (ANSI). */ |
| "USR2", SIGUSR2, /* User-defined signal 2 (POSIX). */ |
| "PIPE", SIGPIPE, /* Broken pipe (POSIX). */ |
| "ALRM", SIGALRM, /* Alarm clock (POSIX). */ |
| "TERM", SIGTERM, /* Termination (ANSI). */ |
| #ifdef SIGSTKFLT |
| "STKFLT", SIGSTKFLT, /* Stack fault. */ |
| #endif |
| "CLD", SIGCLD, /* Same as SIGCHLD (System V). */ |
| "CHLD", SIGCHLD, /* Child status has changed (POSIX). */ |
| "CONT", SIGCONT, /* Continue (POSIX). */ |
| "STOP", SIGSTOP, /* Stop, unblockable (POSIX). */ |
| "TSTP", SIGTSTP, /* Keyboard stop (POSIX). */ |
| "TTIN", SIGTTIN, /* Background read from tty (POSIX). */ |
| "TTOU", SIGTTOU, /* Background write to tty (POSIX). */ |
| "URG", SIGURG, /* Urgent condition on socket (4.2 BSD). */ |
| "XCPU", SIGXCPU, /* CPU limit exceeded (4.2 BSD). */ |
| "XFSZ", SIGXFSZ, /* File size limit exceeded (4.2 BSD). */ |
| "VTALRM", SIGVTALRM, /* Virtual alarm clock (4.2 BSD). */ |
| "PROF", SIGPROF, /* Profiling alarm clock (4.2 BSD). */ |
| "WINCH", SIGWINCH, /* Window size change (4.3 BSD, Sun). */ |
| "POLL", SIGPOLL, /* Pollable event occurred (System V). */ |
| "IO", SIGIO, /* I/O now possible (4.2 BSD). */ |
| "PWR", SIGPWR, /* Power failure restart (System V). */ |
| #ifdef SIGSYS |
| "SYS", SIGSYS /* Bad system call. Only on some Linuxen! */ |
| #endif |
| }; |
| |
| JVM_ENTRY_NO_ENV(jint, JVM_FindSignal(const char *name)) |
| |
| /* find and return the named signal's number */ |
| |
| for(uint i=0; i<ARRAY_SIZE(siglabels); i++) |
| if(!strcmp(name, siglabels[i].name)) |
| return siglabels[i].number; |
| |
| return -1; |
| |
| JVM_END |
| |
| // used by os::exception_name() |
| extern bool signal_name(int signo, char* buf, size_t len) { |
| for(uint i = 0; i < ARRAY_SIZE(siglabels); i++) { |
| if (signo == siglabels[i].number) { |
| jio_snprintf(buf, len, "SIG%s", siglabels[i].name); |
| return true; |
| } |
| } |
| return false; |
| } |