1 /*
2 * Copyright (c) 1997, 2012, 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 #ifndef SHARE_VM_UTILITIES_ELF_FILE_HPP
26 #define SHARE_VM_UTILITIES_ELF_FILE_HPP
27
28 #if !defined(_WINDOWS) && !defined(__APPLE__)
29
30 #if defined(__OpenBSD__)
31 #include <sys/exec_elf.h>
32 #else
33 #include <elf.h>
34 #endif
35 #include <stdio.h>
36
37 #ifdef _LP64
38
39 typedef Elf64_Half Elf_Half;
40 typedef Elf64_Word Elf_Word;
41 typedef Elf64_Off Elf_Off;
42 typedef Elf64_Addr Elf_Addr;
43
44 typedef Elf64_Ehdr Elf_Ehdr;
45 typedef Elf64_Shdr Elf_Shdr;
46 typedef Elf64_Phdr Elf_Phdr;
47 typedef Elf64_Sym Elf_Sym;
48
49 #if !defined(_ALLBSD_SOURCE) || defined(__APPLE__)
50 #define ELF_ST_TYPE ELF64_ST_TYPE
51 #endif
52
53 #else
54
55 typedef Elf32_Half Elf_Half;
56 typedef Elf32_Word Elf_Word;
57 typedef Elf32_Off Elf_Off;
58 typedef Elf32_Addr Elf_Addr;
59
60
61 typedef Elf32_Ehdr Elf_Ehdr;
62 typedef Elf32_Shdr Elf_Shdr;
63 typedef Elf32_Phdr Elf_Phdr;
64 typedef Elf32_Sym Elf_Sym;
65
66 #if !defined(_ALLBSD_SOURCE) || defined(__APPLE__)
67 #define ELF_ST_TYPE ELF32_ST_TYPE
68 #endif
69 #endif
70
71 #include "globalDefinitions.hpp"
72 #include "memory/allocation.hpp"
73 #include "utilities/decoder.hpp"
74
75
76 class ElfStringTable;
77 class ElfSymbolTable;
78
79
80 // On Solaris/Linux platforms, libjvm.so does contain all private symbols.
81 // ElfFile is basically an elf file parser, which can lookup the symbol
82 // that is the nearest to the given address.
83 // Beware, this code is called from vm error reporting code, when vm is already
84 // in "error" state, so there are scenarios, lookup will fail. We want this
85 // part of code to be very defensive, and bait out if anything went wrong.
86
87 class ElfFile: public CHeapObj<mtInternal> {
88 friend class ElfDecoder;
89 public:
90 ElfFile(const char* filepath);
91 ~ElfFile();
92
93 bool decode(address addr, char* buf, int buflen, int* offset);
94 const char* filepath() {
95 return m_filepath;
96 }
97
98 bool same_elf_file(const char* filepath) {
99 assert(filepath, "null file path");
100 assert(m_filepath, "already out of memory");
101 return (m_filepath && !strcmp(filepath, m_filepath));
102 }
103
104 NullDecoder::decoder_status get_status() {
105 return m_status;
106 }
107
108 private:
109 // sanity check, if the file is a real elf file
110 bool is_elf_file(Elf_Ehdr&);
111
112 // load string tables from the elf file
113 bool load_tables();
114
115 // string tables are stored in a linked list
116 void add_string_table(ElfStringTable* table);
117
118 // symbol tables are stored in a linked list
119 void add_symbol_table(ElfSymbolTable* table);
120
121 // return a string table at specified section index
122 ElfStringTable* get_string_table(int index);
123
124 protected:
125 ElfFile* next() const { return m_next; }
126 void set_next(ElfFile* file) { m_next = file; }
127
128 public:
129 // Returns true if the elf file is marked NOT to require an executable stack,
130 // or if the file could not be opened.
131 // Returns false if the elf file requires an executable stack, the stack flag
132 // is not set at all, or if the file can not be read.
133 // On systems other than linux it always returns false.
134 bool specifies_noexecstack() NOT_LINUX({ return false; });
135
136 protected:
137 ElfFile* m_next;
138
139 private:
140 // file
141 const char* m_filepath;
142 FILE* m_file;
143
144 // Elf header
145 Elf_Ehdr m_elfHdr;
146
147 // symbol tables
148 ElfSymbolTable* m_symbol_tables;
149
150 // string tables
151 ElfStringTable* m_string_tables;
152
153 NullDecoder::decoder_status m_status;
154 };
155
156 #endif // _WINDOWS
157
158 #endif // SHARE_VM_UTILITIES_ELF_FILE_HPP