regs.c revision 44ae188c8dcd2727e383dcac0d46c3f784d0da5f 
1/*
2 * This file is part of ltrace.
3 * Copyright (C) 2013 Petr Machata, Red Hat Inc.
4 * Copyright (C) 2008,2009 Juan Cespedes
5 * Copyright (C) 2006 Eric Vaitl, Cisco Systems, Inc.
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 <stddef.h>
26#include <sys/types.h>
27#include <sys/ptrace.h>
28#include <asm/ptrace.h>
29
30#include "proc.h"
31#include "common.h"
32#include "mips.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
42/**
43   \addtogroup mips
44   @{
45 */
46
47
48/**
49   \param proc The process to work on.
50   \return The current instruction pointer.
51 */
52void *
53get_instruction_pointer(struct process *proc)
54{
55	return (void *)ptrace(PTRACE_PEEKUSER, proc->pid, off_pc, 0);
56}
57
58/**
59   \param proc The process to work on.
60   \param addr The address to set to.
61
62   Called by \c continue_after_breakpoint().
63
64   \todo Our mips kernel ptrace doesn't support PTRACE_SINGLESTEP, so
65   we \c continue_process() after a breakpoint. Check if this is OK.
66 */
67void
68set_instruction_pointer(struct process *proc, void *addr)
69{
70	ptrace(PTRACE_POKEUSER, proc->pid, off_pc, addr);
71}
72
73/**
74   \param proc The process to work on.
75   \return The current stack pointer.
76 */
77void *
78get_stack_pointer(struct process *proc)
79{
80	return (void *)ptrace(PTRACE_PEEKUSER, proc->pid, off_sp, 0);
81}
82
83/**
84   \param proc The process to work on.
85   \param stack_pointer The current stack pointer for proc
86   \return The current return address.
87
88   Called by \c handle_breakpoint().
89
90   Mips uses r31 for the return address, so the stack_pointer is
91   unused.
92 */
93void *
94get_return_addr(struct process *proc, void *stack_pointer)
95{
96	return (void *)ptrace(PTRACE_PEEKUSER, proc->pid, off_lr, 0);
97}
98