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 */
52 void *
get_instruction_pointer(struct process * proc)53 get_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 */
67 void
set_instruction_pointer(struct process * proc,void * addr)68 set_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 */
77 void *
get_stack_pointer(struct process * proc)78 get_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 */
93 void *
get_return_addr(struct process * proc,void * stack_pointer)94 get_return_addr(struct process *proc, void *stack_pointer)
95 {
96 return (void *)ptrace(PTRACE_PEEKUSER, proc->pid, off_lr, 0);
97 }
98