1 /*
2 * This file is part of ltrace.
3 * Copyright (C) 2010 Edgar E. Iglesias
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation; either version 2 of the
8 * License, or (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
18 * 02110-1301 USA
19 */
20
21 #if HAVE_CONFIG_H
22 #include "config.h"
23 #endif
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 #include <elf.h>
31
32 #include "proc.h"
33 #include "common.h"
34
35 #if (!defined(PTRACE_PEEKUSER) && defined(PTRACE_PEEKUSR))
36 # define PTRACE_PEEKUSER PTRACE_PEEKUSR
37 #endif
38
39 #if (!defined(PTRACE_POKEUSER) && defined(PTRACE_POKEUSR))
40 # define PTRACE_POKEUSER PTRACE_POKEUSR
41 #endif
42
get_arch_dep(struct process * proc)43 void get_arch_dep(struct process *proc)
44 {
45 }
46
47 /* Returns 1 if syscall, 2 if sysret, 0 otherwise.
48 */
49 #define SYSCALL_INSN 0xe93d
syscall_p(struct process * proc,int status,int * sysnum)50 int syscall_p(struct process *proc, int status, int *sysnum)
51 {
52 if (WIFSTOPPED(status)
53 && WSTOPSIG(status) == (SIGTRAP | proc->tracesysgood)) {
54 long pc = (long)get_instruction_pointer(proc);
55 unsigned int insn =
56 (int)ptrace(PTRACE_PEEKTEXT, proc->pid, pc - sizeof(long),
57 0);
58
59 if ((insn >> 16) == SYSCALL_INSN) {
60 *sysnum =
61 (int)ptrace(PTRACE_PEEKUSER, proc->pid,
62 sizeof(long) * PT_R9, 0);
63 if (proc->callstack_depth > 0
64 && proc->callstack[proc->callstack_depth -
65 1].is_syscall) {
66 return 2;
67 }
68 return 1;
69 }
70 }
71 return 0;
72 }
73
gimme_arg(enum tof type,struct process * proc,int arg_num,struct arg_type_info * info)74 long gimme_arg(enum tof type, struct process *proc, int arg_num,
75 struct arg_type_info *info)
76 {
77 int pid = proc->pid;
78
79 if (arg_num == -1) { /* return value */
80 return ptrace(PTRACE_PEEKUSER, pid, PT_R10 * 4, 0);
81 } else if (arg_num < 6) {
82 int pt_arg[6] =
83 {
84 PT_ORIG_R10, PT_R11, PT_R12, PT_R13, PT_MOF,
85 PT_SRP
86 };
87 return ptrace(PTRACE_PEEKUSER, pid, pt_arg[arg_num] * 4, 0);
88 } else {
89 return ptrace(PTRACE_PEEKDATA, pid,
90 proc->stack_pointer + 4 * (arg_num - 6), 0);
91 }
92 return 0;
93 }
94