1 /* 2 * Copyright (c) 2003, 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. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 # include "incls/_precompiled.incl" 26 # include "incls/_vmError_linux.cpp.incl" 27 28 #include <sys/types.h> 29 #include <sys/wait.h> 30 #include <sys/syscall.h> 31 #include <unistd.h> 32 #include <signal.h> 33 34 void VMError::show_message_box(char *buf, int buflen) { 35 bool yes; 36 do { 37 error_string(buf, buflen); 38 int len = (int)strlen(buf); 39 char *p = &buf[len]; 40 41 jio_snprintf(p, buflen - len, 42 "\n\n" 43 "Do you want to debug the problem?\n\n" 44 "To debug, run 'gdb /proc/%d/exe %d'; then switch to thread " INTX_FORMAT "\n" 45 "Enter 'yes' to launch gdb automatically (PATH must include gdb)\n" 46 "Otherwise, press RETURN to abort...", 47 os::current_process_id(), os::current_process_id(), 48 os::current_thread_id()); 49 50 yes = os::message_box("Unexpected Error", buf); 51 52 if (yes) { 53 // yes, user asked VM to launch debugger 54 jio_snprintf(buf, buflen, "gdb /proc/%d/exe %d", 55 os::current_process_id(), os::current_process_id()); 56 57 os::fork_and_exec(buf); 58 yes = false; 59 } 60 } while (yes); 61 } 62 63 // Space for our "saved" signal flags and handlers 64 static int resettedSigflags[2]; 65 static address resettedSighandler[2]; 66 67 static void save_signal(int idx, int sig) 68 { 69 struct sigaction sa; 70 sigaction(sig, NULL, &sa); 71 resettedSigflags[idx] = sa.sa_flags; 72 resettedSighandler[idx] = (sa.sa_flags & SA_SIGINFO) 73 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction) 74 : CAST_FROM_FN_PTR(address, sa.sa_handler); 75 } 76 77 int VMError::get_resetted_sigflags(int sig) { 78 if(SIGSEGV == sig) { 79 return resettedSigflags[0]; 80 } else if(SIGBUS == sig) { 81 return resettedSigflags[1]; 82 } 83 return -1; 84 } 85 86 address VMError::get_resetted_sighandler(int sig) { 87 if(SIGSEGV == sig) { 88 return resettedSighandler[0]; 89 } else if(SIGBUS == sig) { 90 return resettedSighandler[1]; 91 } 92 return NULL; 93 } 94 95 static void crash_handler(int sig, siginfo_t* info, void* ucVoid) { 96 // unmask current signal 97 sigset_t newset; 98 sigemptyset(&newset); 99 sigaddset(&newset, sig); 100 sigprocmask(SIG_UNBLOCK, &newset, NULL); 101 102 VMError err(NULL, sig, NULL, info, ucVoid); 103 err.report_and_die(); 104 } 105 106 void VMError::reset_signal_handlers() { 107 // Save sigflags for resetted signals 108 save_signal(0, SIGSEGV); 109 save_signal(1, SIGBUS); 110 os::signal(SIGSEGV, CAST_FROM_FN_PTR(void *, crash_handler)); 111 os::signal(SIGBUS, CAST_FROM_FN_PTR(void *, crash_handler)); 112 }