regs.c revision bc0de433c25d224cf5f4743ba4a78131267c532d 
1/*
2 * This file is part of ltrace.
3 * Copyright (C) 2008,2009 Juan Cespedes
4 * Copyright (C) 2006 Eric Vaitl, Cisco Systems, Inc.
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 "config.h"
23
24#include <stddef.h>
25#include <sys/types.h>
26#include <sys/ptrace.h>
27#include <asm/ptrace.h>
28
29#include "proc.h"
30#include "common.h"
31#include "mips.h"
32
33#if (!defined(PTRACE_PEEKUSER) && defined(PTRACE_PEEKUSR))
34# define PTRACE_PEEKUSER PTRACE_PEEKUSR
35#endif
36
37#if (!defined(PTRACE_POKEUSER) && defined(PTRACE_POKEUSR))
38# define PTRACE_POKEUSER PTRACE_POKEUSR
39#endif
40
41/**
42   \addtogroup mips
43   @{
44 */
45
46
47/**
48   \param proc The process to work on.
49   \return The current instruction pointer.
50 */
51void *
52get_instruction_pointer(struct process *proc)
53{
54	return (void *)ptrace(PTRACE_PEEKUSER, proc->pid, off_pc, 0);
55}
56
57/**
58   \param proc The process to work on.
59   \param addr The address to set to.
60
61   Called by \c continue_after_breakpoint().
62
63   \todo Our mips kernel ptrace doesn't support PTRACE_SINGLESTEP, so
64   we \c continue_process() after a breakpoint. Check if this is OK.
65 */
66void
67set_instruction_pointer(struct process *proc, void *addr)
68{
69	ptrace(PTRACE_POKEUSER, proc->pid, off_pc, addr);
70}
71
72/**
73   \param proc The process to work on.
74   \return The current stack pointer.
75 */
76void *
77get_stack_pointer(struct process *proc)
78{
79	return (void *)ptrace(PTRACE_PEEKUSER, proc->pid, off_sp, 0);
80}
81
82/**
83   \param proc The process to work on.
84   \param stack_pointer The current stack pointer for proc
85   \return The current return address.
86
87   Called by \c handle_breakpoint().
88
89   Mips uses r31 for the return address, so the stack_pointer is
90   unused.
91 */
92void *
93get_return_addr(struct process *proc, void *stack_pointer)
94{
95	return (void *)ptrace(PTRACE_PEEKUSER, proc->pid, off_lr, 0);
96}
97
98void
99set_return_addr(struct process *proc, void *addr)
100{
101	ptrace(PTRACE_POKEUSER, proc->pid, off_lr, addr);
102}
103