Zhengyu Gu | 43bb087 | 2012-01-17 13:08:52 -0500 | [diff] [blame] | 1 | /* |
Kim Barrett | 6cc7e33 | 2017-06-22 20:47:22 -0400 | [diff] [blame] | 2 | * Copyright (c) 2011, 2017, Oracle and/or its affiliates. All rights reserved. |
Zhengyu Gu | 43bb087 | 2012-01-17 13:08:52 -0500 | [diff] [blame] | 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 | #ifdef __APPLE__ |
Kim Barrett | 6cc7e33 | 2017-06-22 20:47:22 -0400 | [diff] [blame] | 28 | #include "prims/jvm.h" |
Zhengyu Gu | 43bb087 | 2012-01-17 13:08:52 -0500 | [diff] [blame] | 29 | #include "decoder_machO.hpp" |
Zhengyu Gu | 5515df5 | 2012-07-30 10:25:52 -0400 | [diff] [blame] | 30 | |
| 31 | #include <cxxabi.h> |
| 32 | #include <mach-o/loader.h> |
| 33 | #include <mach-o/nlist.h> |
| 34 | |
| 35 | |
| 36 | bool MachODecoder::demangle(const char* symbol, char *buf, int buflen) { |
| 37 | int status; |
| 38 | char* result; |
| 39 | size_t size = (size_t)buflen; |
| 40 | // Don't pass buf to __cxa_demangle. In case of the 'buf' is too small, |
| 41 | // __cxa_demangle will call system "realloc" for additional memory, which |
| 42 | // may use different malloc/realloc mechanism that allocates 'buf'. |
| 43 | if ((result = abi::__cxa_demangle(symbol, NULL, NULL, &status)) != NULL) { |
| 44 | jio_snprintf(buf, buflen, "%s", result); |
| 45 | // call c library's free |
| 46 | ::free(result); |
| 47 | return true; |
| 48 | } |
| 49 | return false; |
| 50 | } |
| 51 | |
| 52 | bool MachODecoder::decode(address addr, char *buf, |
| 53 | int buflen, int *offset, const void *mach_base) { |
| 54 | struct symtab_command * symt = (struct symtab_command *) |
| 55 | mach_find_command((struct mach_header_64 *)mach_base, LC_SYMTAB); |
| 56 | if (symt == NULL) { |
David Chase | 305ec3b | 2014-05-09 16:50:54 -0400 | [diff] [blame] | 57 | DEBUG_ONLY(tty->print_cr("no symtab in mach file at 0x%lx", p2i(mach_base))); |
Zhengyu Gu | 5515df5 | 2012-07-30 10:25:52 -0400 | [diff] [blame] | 58 | return false; |
| 59 | } |
| 60 | uint32_t off = symt->symoff; /* symbol table offset (within this mach file) */ |
| 61 | uint32_t nsyms = symt->nsyms; /* number of symbol table entries */ |
| 62 | uint32_t stroff = symt->stroff; /* string table offset */ |
| 63 | uint32_t strsize = symt->strsize; /* string table size in bytes */ |
| 64 | |
| 65 | // iterate through symbol table trying to match our offset |
| 66 | |
| 67 | uint32_t addr_relative = (uintptr_t) mach_base - (uintptr_t) addr; // offset we seek in the symtab |
| 68 | void * symtab_addr = (void*) ((uintptr_t) mach_base + off); |
| 69 | struct nlist_64 *cur_nlist = (struct nlist_64 *) symtab_addr; |
| 70 | struct nlist_64 *last_nlist = cur_nlist; // no size stored in an entry, so keep previously seen nlist |
| 71 | |
| 72 | int32_t found_strx = 0; |
| 73 | int32_t found_symval = 0; |
| 74 | |
| 75 | for (uint32_t i=0; i < nsyms; i++) { |
| 76 | uint32_t this_value = cur_nlist->n_value; |
| 77 | |
| 78 | if (addr_relative == this_value) { |
| 79 | found_strx = cur_nlist->n_un.n_strx; |
| 80 | found_symval = this_value; |
| 81 | break; |
| 82 | } else if (addr_relative > this_value) { |
| 83 | // gone past it, use previously seen nlist: |
| 84 | found_strx = last_nlist->n_un.n_strx; |
| 85 | found_symval = last_nlist->n_value; |
| 86 | break; |
| 87 | } |
| 88 | last_nlist = cur_nlist; |
| 89 | cur_nlist = cur_nlist + sizeof(struct nlist_64); |
| 90 | } |
| 91 | if (found_strx == 0) { |
| 92 | return false; |
| 93 | } |
| 94 | // write the offset: |
| 95 | *offset = addr_relative - found_symval; |
| 96 | |
| 97 | // lookup found_strx in the string table |
| 98 | char * symname = mach_find_in_stringtable((char*) ((uintptr_t)mach_base + stroff), strsize, found_strx); |
| 99 | if (symname) { |
| 100 | strncpy(buf, symname, buflen); |
Thomas Stuefe | c034b74 | 2015-04-07 14:19:03 +0200 | [diff] [blame] | 101 | buf[buflen - 1] = '\0'; |
Zhengyu Gu | 5515df5 | 2012-07-30 10:25:52 -0400 | [diff] [blame] | 102 | return true; |
| 103 | } |
| 104 | DEBUG_ONLY(tty->print_cr("no string or null string found.")); |
| 105 | return false; |
| 106 | } |
| 107 | |
| 108 | void* MachODecoder::mach_find_command(struct mach_header_64 * mach_base, uint32_t command_wanted) { |
| 109 | // possibly verify it is a mach_header, use magic number. |
| 110 | // commands begin immediately after the header. |
| 111 | struct load_command *pos = (struct load_command *) mach_base + sizeof(struct mach_header_64); |
| 112 | for (uint32_t i = 0; i < mach_base->ncmds; i++) { |
| 113 | struct load_command *this_cmd = (struct load_command *) pos; |
| 114 | if (this_cmd->cmd == command_wanted) { |
| 115 | return pos; |
| 116 | } |
| 117 | int cmdsize = this_cmd->cmdsize; |
| 118 | pos += cmdsize; |
| 119 | } |
| 120 | return NULL; |
| 121 | } |
| 122 | |
| 123 | char* MachODecoder::mach_find_in_stringtable(char *strtab, uint32_t tablesize, int strx_wanted) { |
| 124 | |
| 125 | if (strx_wanted == 0) { |
| 126 | return NULL; |
| 127 | } |
| 128 | char *strtab_end = strtab + tablesize; |
| 129 | |
| 130 | // find the first string, skip over the space char |
| 131 | // (or the four zero bytes we see e.g. in libclient) |
| 132 | if (*strtab == ' ') { |
| 133 | strtab++; |
| 134 | if (*strtab != 0) { |
| 135 | DEBUG_ONLY(tty->print_cr("string table has leading space but no following zero.")); |
| 136 | return NULL; |
| 137 | } |
| 138 | strtab++; |
| 139 | } else { |
| 140 | if ((uint32_t) *strtab != 0) { |
| 141 | DEBUG_ONLY(tty->print_cr("string table without leading space or leading int of zero.")); |
| 142 | return NULL; |
| 143 | } |
| 144 | strtab+=4; |
| 145 | } |
| 146 | // read the real strings starting at index 1 |
| 147 | int cur_strx = 1; |
| 148 | while (strtab < strtab_end) { |
| 149 | if (cur_strx == strx_wanted) { |
| 150 | return strtab; |
| 151 | } |
| 152 | // find start of next string |
| 153 | while (*strtab != 0) { |
| 154 | strtab++; |
| 155 | } |
| 156 | strtab++; // skip the terminating zero |
| 157 | cur_strx++; |
| 158 | } |
| 159 | DEBUG_ONLY(tty->print_cr("string number %d not found.", strx_wanted)); |
| 160 | return NULL; |
| 161 | } |
| 162 | |
| 163 | |
Zhengyu Gu | 43bb087 | 2012-01-17 13:08:52 -0500 | [diff] [blame] | 164 | #endif |
| 165 | |
| 166 | |