1 /* 2 * Copyright (c) 1999, 2014, 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 "runtime/os.hpp" 26 27 #ifndef OS_POSIX_VM_OS_POSIX_HPP 28 #define OS_POSIX_VM_OS_POSIX_HPP 29 30 // File conventions 31 static const char* file_separator() { return "/"; } 32 static const char* line_separator() { return "\n"; } 33 static const char* path_separator() { return ":"; } 34 35 class Posix { 36 friend class os; 37 38 protected: 39 static void print_distro_info(outputStream* st); 40 static void print_rlimit_info(outputStream* st); 41 static void print_uname_info(outputStream* st); 42 static void print_libversion_info(outputStream* st); 43 static void print_load_average(outputStream* st); 44 45 public: 46 47 // Returns true if signal is valid. 48 static bool is_valid_signal(int sig); 49 50 // Helper function, returns a string (e.g. "SIGILL") for a signal. 51 // Returned string is a constant. For unknown signals "UNKNOWN" is returned. 52 static const char* get_signal_name(int sig, char* out, size_t outlen); 53 54 // Returns one-line short description of a signal set in a user provided buffer. 55 static const char* describe_signal_set_short(const sigset_t* set, char* buffer, size_t size); 56 57 // Prints a short one-line description of a signal set. 58 static void print_signal_set_short(outputStream* st, const sigset_t* set); 59 60 // Writes a one-line description of a combination of sigaction.sa_flags 61 // into a user provided buffer. Returns that buffer. 62 static const char* describe_sa_flags(int flags, char* buffer, size_t size); 63 64 // Prints a one-line description of a combination of sigaction.sa_flags. 65 static void print_sa_flags(outputStream* st, int flags); 66 67 // A POSIX conform, platform-independend siginfo print routine. 68 static void print_siginfo_brief(outputStream* os, const siginfo_t* si); 69 70 }; 71 72 /* 73 * Crash protection for the watcher thread. Wrap the callback 74 * with a sigsetjmp and in case of a SIGSEGV/SIGBUS we siglongjmp 75 * back. 76 * To be able to use this - don't take locks, don't rely on destructors, 77 * don't make OS library calls, don't allocate memory, don't print, 78 * don't call code that could leave the heap / memory in an inconsistent state, 79 * or anything else where we are not in control if we suddenly jump out. 80 */ 81 class WatcherThreadCrashProtection : public StackObj { 82 public: 83 WatcherThreadCrashProtection(); 84 bool call(os::CrashProtectionCallback& cb); 85 86 static void check_crash_protection(int signal, Thread* thread); 87 private: 88 void restore(); 89 sigjmp_buf _jmpbuf; 90 }; 91 92 class PosixSemaphore : public Semaphore { 93 public: 94 PosixSemaphore(uint value = 0) : Semaphore(value) {} 95 96 bool trywait(); 97 bool timedwait(struct timespec ts); 98 }; 99 100 #endif // OS_POSIX_VM_OS_POSIX_HPP