1 /*
2 * Copyright (c) 1997, 2018, 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 // status code for decoding native C frame
37 enum decoder_status {
38 not_available = -10, // real decoder is not available
39 no_error = 0, // no error encountered
40 out_of_memory, // out of memory
41 file_invalid, // invalid elf file
42 file_not_found, // could not found symbol file (on windows), such as jvm.pdb or jvm.map
43 helper_func_error, // decoding functions not found (Windows only)
44 helper_init_error // SymInitialize failed (Windows only)
45 };
46
47 protected:
48 decoder_status _decoder_status;
49
50 public:
51 virtual ~AbstractDecoder() {}
52
53 // decode an pc address to corresponding function name and an offset from the beginning of
54 // the function
55 //
56 // Note: the 'base' variant does not demangle names. The
57 // demangling that was done systematically in the 'modulepath' variant
58 // is now optional.
59 virtual bool decode(address pc, char* buf, int buflen, int* offset,
60 const char* modulepath = NULL, bool demangle = true) = 0;
61 virtual bool decode(address pc, char* buf, int buflen, int* offset, const void* base) = 0;
62
63 // demangle a C++ symbol
64 virtual bool demangle(const char* symbol, char* buf, int buflen) = 0;
65
66 virtual decoder_status status() const {
67 return _decoder_status;
68 }
69
70 virtual bool has_error() const {
71 return is_error(_decoder_status);
72 }
73
74 static bool is_error(decoder_status status) {
75 return (status > no_error);
76 }
77 };
78
79 // Do nothing decoder
80 class NullDecoder : public AbstractDecoder {
81 public:
82 NullDecoder() {
83 _decoder_status = not_available;
84 }
85
86 virtual ~NullDecoder() {};
87
88 virtual bool decode(address pc, char* buf, int buflen, int* offset,
89 const char* modulepath, bool demangle) {
90 return false;
91 }
92
93 virtual bool decode(address pc, char* buf, int buflen, int* offset, const void* base) {
94 return false;
95 }
96
97 virtual bool demangle(const char* symbol, char* buf, int buflen) {
98 return false;
99 }
100 };
101
102 class Decoder : AllStatic {
103 public:
104 static bool decode(address pc, char* buf, int buflen, int* offset, const char* modulepath = NULL, bool demangle = true);
105 static bool decode(address pc, char* buf, int buflen, int* offset, bool demangle) {
106 return decode(pc, buf, buflen, offset, (const char*) NULL, demangle);
107 }
108 static bool decode(address pc, char* buf, int buflen, int* offset, const void* base);
109 static bool demangle(const char* symbol, char* buf, int buflen);
110
111 // Attempts to retrieve source file name and line number associated with a pc.
112 // If buf != NULL, points to a buffer of size buflen which will receive the
113 // file name. File name will be silently truncated if output buffer is too small.
114 static bool get_source_info(address pc, char* buf, size_t buflen, int* line);
115
116 static void print_state_on(outputStream* st);
117
118 protected:
119 // shared decoder instance, _shared_instance_lock is needed
120 static AbstractDecoder* get_shared_instance();
121 // a private instance for error handler. Error handler can be
122 // triggered almost everywhere, including signal handler, where
123 // no lock can be taken. So the shared decoder can not be used
124 // in this scenario.
125 static AbstractDecoder* get_error_handler_instance();
126
127 static AbstractDecoder* create_decoder();
128 private:
129 static AbstractDecoder* _shared_decoder;
130 static AbstractDecoder* _error_handler_decoder;
131 static NullDecoder _do_nothing_decoder;
132
133 protected:
134 static Mutex* shared_decoder_lock();
135
136 friend class DecoderLocker;
137 };
138
139 class DecoderLocker : public MutexLockerEx {
140 AbstractDecoder* _decoder;
141 inline bool is_first_error_thread();
142 public:
143 DecoderLocker();
144 AbstractDecoder* decoder() {
145 return _decoder;
146 }
147 };
148
149 #endif // SHARE_VM_UTILITIES_DECODER_HPP