1 /*
2 * This file is part of ltrace.
3 * Copyright (C) 2004,2008,2009 Juan Cespedes
4 * Copyright (C) 2006 Ian Wienand
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 <sys/types.h>
25 #include <sys/wait.h>
26 #include <signal.h>
27 #include <sys/ptrace.h>
28 #include <asm/ptrace.h>
29
30 #include "proc.h"
31 #include "common.h"
32 #include "debug.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 void
get_arch_dep(struct process * proc)43 get_arch_dep(struct process *proc)
44 {
45 }
46
47 /* Returns 1 if syscall, 2 if sysret, 0 otherwise.
48 */
49 int
syscall_p(struct process * proc,int status,int * sysnum)50 syscall_p(struct process *proc, int status, int *sysnum)
51 {
52 if (WIFSTOPPED(status)
53 && WSTOPSIG(status) == (SIGTRAP | proc->tracesysgood)) {
54 char *ip = get_instruction_pointer(proc) - 4;
55 long x = ptrace(PTRACE_PEEKTEXT, proc->pid, ip, 0);
56 debug(2, "instr: %016lx", x);
57 if ((x & 0xffffffff) != 0x00000083)
58 return 0;
59 *sysnum =
60 ptrace(PTRACE_PEEKUSER, proc->pid, 0 /* REG_R0 */ , 0);
61 if (proc->callstack_depth > 0 &&
62 proc->callstack[proc->callstack_depth - 1].is_syscall &&
63 proc->callstack[proc->callstack_depth - 1].c_un.syscall == *sysnum) {
64 return 2;
65 }
66 if (*sysnum >= 0 && *sysnum < 500) {
67 return 1;
68 }
69 }
70 return 0;
71 }
72
73 long
gimme_arg(enum tof type,struct process * proc,int arg_num,struct arg_type_info * info)74 gimme_arg(enum tof type, struct process *proc, int arg_num,
75 struct arg_type_info *info)
76 {
77 if (arg_num == -1) { /* return value */
78 return ptrace(PTRACE_PEEKUSER, proc->pid, 0 /* REG_R0 */ , 0);
79 }
80
81 if (type == LT_TOF_FUNCTION || type == LT_TOF_FUNCTIONR) {
82 if (arg_num <= 5)
83 return ptrace(PTRACE_PEEKUSER, proc->pid,
84 arg_num + 16 /* REG_A0 */ , 0);
85 else
86 return ptrace(PTRACE_PEEKTEXT, proc->pid,
87 proc->stack_pointer + 8 * (arg_num - 6),
88 0);
89 } else if (type == LT_TOF_SYSCALL || type == LT_TOF_SYSCALLR) {
90 return ptrace(PTRACE_PEEKUSER, proc->pid,
91 arg_num + 16 /* REG_A0 */ , 0);
92 } else {
93 fprintf(stderr, "gimme_arg called with wrong arguments\n");
94 exit(1);
95 }
96 return 0;
97 }
98