1 /* 2 * Copyright (c) 1997, 2017, 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 26 #ifndef SHARE_VM_UTILITIES_DECODER_HPP 27 #define SHARE_VM_UTILITIES_DECODER_HPP 28 29 #include "memory/allocation.hpp" 30 #include "runtime/mutex.hpp" 31 #include "runtime/mutexLocker.hpp" 32 #include "utilities/ostream.hpp" 33 34 class AbstractDecoder : public CHeapObj<mtInternal> { 35 public: 36 virtual ~AbstractDecoder() {} 37 38 // status code for decoding native C frame 39 enum decoder_status { 40 not_available = -10, // real decoder is not available 41 no_error = 0, // successfully decoded frames 42 out_of_memory, // out of memory 43 file_invalid, // invalid elf file 44 file_not_found, // could not found symbol file (on windows), such as jvm.pdb or jvm.map 45 helper_func_error, // decoding functions not found (Windows only) 46 helper_init_error // SymInitialize failed (Windows only) 47 }; 48 49 // decode an pc address to corresponding function name and an offset from the beginning of 50 // the function 51 // 52 // Note: the 'base' variant does not demangle names. The 53 // demangling that was done systematically in the 'modulepath' variant 54 // is now optional. 55 virtual bool decode(address pc, char* buf, int buflen, int* offset, 56 const char* modulepath = NULL, bool demangle = true) = 0; 57 virtual bool decode(address pc, char* buf, int buflen, int* offset, const void* base) = 0; 58 59 // demangle a C++ symbol 60 virtual bool demangle(const char* symbol, char* buf, int buflen) = 0; 61 62 virtual decoder_status status() const { 63 return _decoder_status; 64 } 65 66 virtual bool has_error() const { 67 return is_error(_decoder_status); 68 } 69 70 static bool is_error(decoder_status status) { 71 return (status > 0); 72 } 73 74 protected: 75 decoder_status _decoder_status; 76 }; 77 78 // Do nothing decoder 79 class NullDecoder : public AbstractDecoder { 80 public: 81 NullDecoder() { 82 _decoder_status = not_available; 83 } 84 85 virtual ~NullDecoder() {}; 86 87 virtual bool decode(address pc, char* buf, int buflen, int* offset, 88 const char* modulepath, bool demangle) { 89 return false; 90 } 91 92 virtual bool decode(address pc, char* buf, int buflen, int* offset, const void* base) { 93 return false; 94 } 95 96 virtual bool demangle(const char* symbol, char* buf, int buflen) { 97 return false; 98 } 99 100 }; 101 102 103 class Decoder : AllStatic { 104 public: 105 static bool decode(address pc, char* buf, int buflen, int* offset, const char* modulepath = NULL, bool demangle = true); 106 static bool decode(address pc, char* buf, int buflen, int* offset, bool demangle) { 107 return decode(pc, buf, buflen, offset, (const char*) NULL, demangle); 108 } 109 static bool decode(address pc, char* buf, int buflen, int* offset, const void* base); 110 static bool demangle(const char* symbol, char* buf, int buflen); 111 112 // Attempts to retrieve source file name and line number associated with a pc. 113 // If buf != NULL, points to a buffer of size buflen which will receive the 114 // file name. File name will be silently truncated if output buffer is too small. 115 static bool get_source_info(address pc, char* buf, size_t buflen, int* line); 116 117 static void print_state_on(outputStream* st); 118 119 protected: 120 // shared decoder instance, _shared_instance_lock is needed 121 static AbstractDecoder* get_shared_instance(); 122 // a private instance for error handler. Error handler can be 123 // triggered almost everywhere, including signal handler, where 124 // no lock can be taken. So the shared decoder can not be used 125 // in this scenario. 126 static AbstractDecoder* get_error_handler_instance(); 127 128 static AbstractDecoder* create_decoder(); 129 private: 130 static AbstractDecoder* _shared_decoder; 131 static AbstractDecoder* _error_handler_decoder; 132 static NullDecoder _do_nothing_decoder; 133 134 protected: 135 static Mutex* _shared_decoder_lock; 136 static Mutex* shared_decoder_lock(); 137 138 friend class DecoderLocker; 139 }; 140 141 class DecoderLocker : public MutexLockerEx { 142 AbstractDecoder* _decoder; 143 inline bool is_first_error_thread(); 144 public: 145 DecoderLocker(); 146 AbstractDecoder* decoder() { 147 return _decoder; 148 } 149 }; 150 151 #endif // SHARE_VM_UTILITIES_DECODER_HPP