trace.c revision e99af270a60891e68d465c4cd97dbe29cd1a05e4 
1/*
2 * This file is part of ltrace.
3 * Copyright (C) 1998,2001,2004,2008,2009 Juan Cespedes
4 * Copyright (C) 2009 Juan Cespedes
5 * Copyright (C) 2006 Ian Wienand
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License as
9 * published by the Free Software Foundation; either version 2 of the
10 * License, or (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful, but
13 * WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15 * General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
20 * 02110-1301 USA
21 */
22
23#include "config.h"
24
25#include <sys/types.h>
26#include <sys/wait.h>
27#include <signal.h>
28#include <sys/ptrace.h>
29#include <asm/ptrace.h>
30
31#include "proc.h"
32#include "common.h"
33
34#if (!defined(PTRACE_PEEKUSER) && defined(PTRACE_PEEKUSR))
35# define PTRACE_PEEKUSER PTRACE_PEEKUSR
36#endif
37
38#if (!defined(PTRACE_POKEUSER) && defined(PTRACE_POKEUSR))
39# define PTRACE_POKEUSER PTRACE_POKEUSR
40#endif
41
42void
43get_arch_dep(Process *proc) {
44}
45
46/* Returns 1 if syscall, 2 if sysret, 0 otherwise.
47 */
48int
49syscall_p(Process *proc, int status, int *sysnum) {
50	int depth;
51
52	if (WIFSTOPPED(status)
53	    && WSTOPSIG(status) == (SIGTRAP | proc->tracesysgood)) {
54		*sysnum = ptrace(PTRACE_PEEKUSER, proc->pid, 4 * PT_ORIG_D0, 0);
55		if (*sysnum == -1)
56			return 0;
57		if (*sysnum >= 0) {
58			depth = proc->callstack_depth;
59			if (depth > 0 &&
60					proc->callstack[depth - 1].is_syscall &&
61					proc->callstack[depth - 1].c_un.syscall == *sysnum) {
62				return 2;
63			} else {
64				return 1;
65			}
66		}
67	}
68	return 0;
69}
70