--- old/src/java.base/macosx/native/libjsig/jsig.c 2018-04-05 11:48:48.496966925 +0200 +++ /dev/null 2018-02-16 14:25:25.622524048 +0100 @@ -1,237 +0,0 @@ -/* - * Copyright (c) 2001, 2015, 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. - * - */ - -/* CopyrightVersion 1.2 */ - -/* This is a special library that should be loaded before libc & - * libthread to interpose the signal handler installation functions: - * sigaction(), signal(), sigset(). - * Used for signal-chaining. See RFE 4381843. - */ - -#include -#include -#include -#include -#include -#include -#include - -#define MASK(sig) ((uint32_t)1 << (sig-1)) // 0 is not a signal. -#if (32 < NSIG-1) -#error "Not all signals can be encoded in jvmsigs. Adapt its type!" -#endif -static struct sigaction sact[NSIG]; /* saved signal handlers */ -static uint32_t jvmsigs = 0; /* signals used by jvm */ -static __thread bool reentry = false; /* prevent reentry deadlock (per-thread) */ - -/* used to synchronize the installation of signal handlers */ -static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER; -static pthread_cond_t cond = PTHREAD_COND_INITIALIZER; -static pthread_t tid = 0; - -typedef void (*sa_handler_t)(int); -typedef void (*sa_sigaction_t)(int, siginfo_t *, void *); -typedef sa_handler_t (*signal_t)(int, sa_handler_t); -typedef int (*sigaction_t)(int, const struct sigaction *, struct sigaction *); - -static signal_t os_signal = 0; /* os's version of signal()/sigset() */ -static sigaction_t os_sigaction = 0; /* os's version of sigaction() */ - -static bool jvm_signal_installing = false; -static bool jvm_signal_installed = false; - -static void signal_lock() { - pthread_mutex_lock(&mutex); - /* When the jvm is installing its set of signal handlers, threads - * other than the jvm thread should wait */ - if (jvm_signal_installing) { - if (tid != pthread_self()) { - pthread_cond_wait(&cond, &mutex); - } - } -} - -static void signal_unlock() { - pthread_mutex_unlock(&mutex); -} - -static sa_handler_t call_os_signal(int sig, sa_handler_t disp, - bool is_sigset) { - sa_handler_t res; - - if (os_signal == NULL) { - if (!is_sigset) { - os_signal = (signal_t)dlsym(RTLD_NEXT, "signal"); - } else { - os_signal = (signal_t)dlsym(RTLD_NEXT, "sigset"); - } - if (os_signal == NULL) { - printf("%s\n", dlerror()); - exit(0); - } - } - reentry = true; - res = (*os_signal)(sig, disp); - reentry = false; - return res; -} - -static void save_signal_handler(int sig, sa_handler_t disp) { - sigset_t set; - sact[sig].sa_handler = disp; - sigemptyset(&set); - sact[sig].sa_mask = set; - sact[sig].sa_flags = 0; -} - -static sa_handler_t set_signal(int sig, sa_handler_t disp, bool is_sigset) { - sa_handler_t oldhandler; - bool sigused; - - signal_lock(); - - sigused = (MASK(sig) & jvmsigs) != 0; - if (jvm_signal_installed && sigused) { - /* jvm has installed its signal handler for this signal. */ - /* Save the handler. Don't really install it. */ - oldhandler = sact[sig].sa_handler; - save_signal_handler(sig, disp); - - signal_unlock(); - return oldhandler; - } else if (jvm_signal_installing) { - /* jvm is installing its signal handlers. Install the new - * handlers and save the old ones. jvm uses sigaction(). - * Leave the piece here just in case. */ - oldhandler = call_os_signal(sig, disp, is_sigset); - save_signal_handler(sig, oldhandler); - - /* Record the signals used by jvm */ - jvmsigs |= MASK(sig); - - signal_unlock(); - return oldhandler; - } else { - /* jvm has no relation with this signal (yet). Install the - * the handler. */ - oldhandler = call_os_signal(sig, disp, is_sigset); - - signal_unlock(); - return oldhandler; - } -} - -sa_handler_t signal(int sig, sa_handler_t disp) { - return set_signal(sig, disp, false); -} - -sa_handler_t sigset(int sig, sa_handler_t disp) { - printf("sigset() is not supported by BSD"); - exit(0); - } - -static int call_os_sigaction(int sig, const struct sigaction *act, - struct sigaction *oact) { - if (os_sigaction == NULL) { - os_sigaction = (sigaction_t)dlsym(RTLD_NEXT, "sigaction"); - if (os_sigaction == NULL) { - printf("%s\n", dlerror()); - exit(0); - } - } - return (*os_sigaction)(sig, act, oact); -} - -int sigaction(int sig, const struct sigaction *act, struct sigaction *oact) { - int res; - bool sigused; - struct sigaction oldAct; - - if (reentry) { - return call_os_sigaction(sig, act, oact); - } - - signal_lock(); - - sigused = (MASK(sig) & jvmsigs) != 0; - if (jvm_signal_installed && sigused) { - /* jvm has installed its signal handler for this signal. */ - /* Save the handler. Don't really install it. */ - if (oact != NULL) { - *oact = sact[sig]; - } - if (act != NULL) { - sact[sig] = *act; - } - - signal_unlock(); - return 0; - } else if (jvm_signal_installing) { - /* jvm is installing its signal handlers. Install the new - * handlers and save the old ones. */ - res = call_os_sigaction(sig, act, &oldAct); - sact[sig] = oldAct; - if (oact != NULL) { - *oact = oldAct; - } - - /* Record the signals used by jvm */ - jvmsigs |= MASK(sig); - - signal_unlock(); - return res; - } else { - /* jvm has no relation with this signal (yet). Install the - * the handler. */ - res = call_os_sigaction(sig, act, oact); - - signal_unlock(); - return res; - } -} - -/* The three functions for the jvm to call into */ -void JVM_begin_signal_setting() { - signal_lock(); - jvm_signal_installing = true; - tid = pthread_self(); - signal_unlock(); -} - -void JVM_end_signal_setting() { - signal_lock(); - jvm_signal_installed = true; - jvm_signal_installing = false; - pthread_cond_broadcast(&cond); - signal_unlock(); -} - -struct sigaction *JVM_get_signal_action(int sig) { - /* Does race condition make sense here? */ - if ((MASK(sig) & jvmsigs) != 0) { - return &sact[sig]; - } - return NULL; -}