1 /* 2 * Copyright (c) 1997, 2013, 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 "precompiled.hpp" 26 27 #if !defined(_WINDOWS) && !defined(__APPLE__) 28 29 #include "memory/allocation.inline.hpp" 30 #include "utilities/elfFuncDescTable.hpp" 31 #include "utilities/elfSymbolTable.hpp" 32 33 ElfSymbolTable::ElfSymbolTable(FILE* file, Elf_Shdr shdr) { 34 assert(file, "null file handle"); 35 m_symbols = NULL; 36 m_next = NULL; 37 m_file = file; 38 m_status = NullDecoder::no_error; 39 40 // try to load the string table 41 long cur_offset = ftell(file); 42 if (cur_offset != -1) { 43 // call malloc so we can back up if memory allocation fails. 44 m_symbols = (Elf_Sym*)os::malloc(shdr.sh_size, mtInternal); 45 if (m_symbols) { 46 if (fseek(file, shdr.sh_offset, SEEK_SET) || 47 fread((void*)m_symbols, shdr.sh_size, 1, file) != 1 || 48 fseek(file, cur_offset, SEEK_SET)) { 49 m_status = NullDecoder::file_invalid; 50 os::free(m_symbols); 51 m_symbols = NULL; 52 } 53 } 54 if (!NullDecoder::is_error(m_status)) { 55 memcpy(&m_shdr, &shdr, sizeof(Elf_Shdr)); 56 } 57 } else { 58 m_status = NullDecoder::file_invalid; 59 } 60 } 61 62 ElfSymbolTable::~ElfSymbolTable() { 63 if (m_symbols != NULL) { 64 os::free(m_symbols); 65 } 66 67 if (m_next != NULL) { 68 delete m_next; 69 } 70 } 71 72 bool ElfSymbolTable::compare(const Elf_Sym* sym, address addr, int* stringtableIndex, int* posIndex, int* offset, ElfFuncDescTable* funcDescTable) { 73 if (STT_FUNC == ELF_ST_TYPE(sym->st_info)) { 74 Elf_Word st_size = sym->st_size; 75 address sym_addr; 76 if (funcDescTable != NULL && funcDescTable->get_index() == sym->st_shndx) { 77 // We need to go another step trough the function descriptor table (currently PPC64 only) 78 sym_addr = funcDescTable->lookup(sym->st_value); 79 } else { 80 sym_addr = (address)sym->st_value; 81 } 82 if (sym_addr <= addr && (Elf_Word)(addr - sym_addr) < st_size) { 83 *offset = (int)(addr - sym_addr); 84 *posIndex = sym->st_name; 85 *stringtableIndex = m_shdr.sh_link; 86 return true; 87 } 88 } 89 return false; 90 } 91 92 bool ElfSymbolTable::lookup(address addr, int* stringtableIndex, int* posIndex, int* offset, ElfFuncDescTable* funcDescTable) { 93 assert(stringtableIndex, "null string table index pointer"); 94 assert(posIndex, "null string table offset pointer"); 95 assert(offset, "null offset pointer"); 96 97 if (NullDecoder::is_error(m_status)) { 98 return false; 99 } 100 101 size_t sym_size = sizeof(Elf_Sym); 102 assert((m_shdr.sh_size % sym_size) == 0, "check size"); 103 int count = m_shdr.sh_size / sym_size; 104 if (m_symbols != NULL) { 105 for (int index = 0; index < count; index ++) { 106 if (compare(&m_symbols[index], addr, stringtableIndex, posIndex, offset, funcDescTable)) { 107 return true; 108 } 109 } 110 } else { 111 long cur_pos; 112 if ((cur_pos = ftell(m_file)) == -1 || 113 fseek(m_file, m_shdr.sh_offset, SEEK_SET)) { 114 m_status = NullDecoder::file_invalid; 115 return false; 116 } 117 118 Elf_Sym sym; 119 for (int index = 0; index < count; index ++) { 120 if (fread(&sym, sym_size, 1, m_file) == 1) { 121 if (compare(&sym, addr, stringtableIndex, posIndex, offset, funcDescTable)) { 122 return true; 123 } 124 } else { 125 m_status = NullDecoder::file_invalid; 126 return false; 127 } 128 } 129 fseek(m_file, cur_pos, SEEK_SET); 130 } 131 return false; 132 } 133 134 #endif // !_WINDOWS && !__APPLE__