/* Locate the shared object symbol nearest a given address. Copyright (C) 1996, 1997, 1998, 1999 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Library General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. The GNU C Library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public License for more details. You should have received a copy of the GNU Library General Public License along with the GNU C Library; see the file COPYING.LIB. If not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #include <dlfcn.h> #include <stddef.h> #include <elf/ldsodefs.h> int internal_function _dl_addr (const void *address, Dl_info *info) { const ElfW(Addr) addr = (ElfW(Addr)) address; struct link_map *l, *match; const ElfW(Sym) *symtab, *matchsym; const char *strtab; /* Find the highest-addressed object that ADDRESS is not below. */ match = NULL; for (l = _dl_loaded; l; l = l->l_next) if (l->l_addr != 0 /* Make sure we do not currently set this map up in this moment. */ && addr >= l->l_addr && (!match || match->l_addr < l->l_addr)) match = l; if (match) { /* We know ADDRESS lies within MATCH if in any shared object. Make sure it isn't past the end of MATCH's segments. */ size_t n = match->l_phnum; if (n > 0) { do --n; while (match->l_phdr[n].p_type != PT_LOAD); if (addr >= (match->l_addr + match->l_phdr[n].p_vaddr + match->l_phdr[n].p_memsz)) /* Off the end of the highest-addressed shared object. */ return 0; } } else return 0; /* Now we know what object the address lies in. */ info->dli_fname = match->l_name; info->dli_fbase = (void *) match->l_addr; symtab = (const void *) match->l_info[DT_SYMTAB]->d_un.d_ptr; strtab = (const void *) match->l_info[DT_STRTAB]->d_un.d_ptr; /* We assume that the string table follows the symbol table, because there is no way in ELF to know the size of the dynamic symbol table!! */ for (matchsym = NULL; (void *) symtab < (void *) strtab; ++symtab) if (addr >= match->l_addr + symtab->st_value && (!matchsym || (matchsym->st_value < symtab->st_value && (ELFW(ST_BIND) (symtab->st_info) == STB_GLOBAL || ELFW(ST_BIND) (symtab->st_info) == STB_WEAK)))) matchsym = symtab; if (matchsym) { /* We found a symbol close by. Fill in its name and exact address. */ info->dli_sname = strtab + matchsym->st_name; info->dli_saddr = (void *) (match->l_addr + matchsym->st_value); } else { /* No symbol matches. We return only the containing object. */ info->dli_sname = NULL; info->dli_saddr = NULL; } return 1; }