plt.c revision 929bd57ca202fd2f2e8485ebf65d683e664f67b5 
1/*
2 * This file is part of ltrace.
3 * Copyright (C) 2010 Zach Welch, CodeSourcery
4 * Copyright (C) 2004,2008,2009 Juan Cespedes
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License as
8 * published by the Free Software Foundation; either version 2 of the
9 * License, or (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful, but
12 * WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14 * General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
19 * 02110-1301 USA
20 */
21
22#include <gelf.h>
23
24#include "proc.h"
25#include "library.h"
26#include "ltrace-elf.h"
27
28static int
29arch_plt_entry_has_stub(struct ltelf *lte, size_t off) {
30	uint16_t op = *(uint16_t *)((char *)lte->relplt->d_buf + off);
31	return op == 0x4778;
32}
33
34GElf_Addr
35arch_plt_sym_val(struct ltelf *lte, size_t ndx, GElf_Rela * rela) {
36	size_t start = lte->relplt->d_size + 12;
37	size_t off = start + 20, i;
38	for (i = 0; i < ndx; i++)
39		off += arch_plt_entry_has_stub(lte, off) ? 16 : 12;
40	if (arch_plt_entry_has_stub(lte, off))
41		off += 4;
42	return lte->plt_addr + off - start;
43}
44
45void *
46sym2addr(struct process *proc, struct library_symbol *sym)
47{
48	return sym->enter_addr;
49}
50