xref: /freebsd/lib/libproc/proc_regs.c (revision b740c88bfb6453416926271c089262e7164dace3)
1 /*
2  * Copyright (c) 2010 The FreeBSD Foundation
3  * All rights reserved.
4  *
5  * This software was developed by Rui Paulo under sponsorship from the
6  * FreeBSD Foundation.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #include <sys/cdefs.h>
31 __FBSDID("$FreeBSD$");
32 
33 #include <sys/types.h>
34 #include <sys/ptrace.h>
35 
36 #include <err.h>
37 #include <stdio.h>
38 #include <string.h>
39 #include <errno.h>
40 #include "_libproc.h"
41 
42 int
43 proc_regget(struct proc_handle *phdl, proc_reg_t reg, unsigned long *regvalue)
44 {
45 	struct reg regs;
46 
47 	if (phdl->status == PS_DEAD || phdl->status == PS_UNDEAD ||
48 	    phdl->status == PS_IDLE) {
49 		errno = ENOENT;
50 		return (-1);
51 	}
52 	memset(&regs, 0, sizeof(regs));
53 	if (ptrace(PT_GETREGS, proc_getpid(phdl), (caddr_t)&regs, 0) < 0)
54 		return (-1);
55 	switch (reg) {
56 	case REG_PC:
57 #if defined(__amd64__)
58 		*regvalue = regs.r_rip;
59 #elif defined(__arm__)
60 		*regvalue = regs.r_pc;
61 #elif defined(__i386__)
62 		*regvalue = regs.r_eip;
63 #elif defined(__mips__)
64 		*regvalue = regs.r_regs[PC];
65 #elif defined(__powerpc__)
66 		*regvalue = regs.pc;
67 #endif
68 		break;
69 	case REG_SP:
70 #if defined(__amd64__)
71 		*regvalue = regs.r_rsp;
72 #elif defined(__arm__)
73 		*regvalue = regs.r_sp;
74 #elif defined(__i386__)
75 		*regvalue = regs.r_esp;
76 #elif defined(__mips__)
77 		*regvalue = regs.r_regs[SP];
78 #elif defined(__powerpc__)
79 		*regvalue = regs.fixreg[1];
80 #endif
81 		break;
82 	default:
83 		DPRINTFX("ERROR: no support for reg number %d", reg);
84 		return (-1);
85 	}
86 
87 	return (0);
88 }
89 
90 int
91 proc_regset(struct proc_handle *phdl, proc_reg_t reg, unsigned long regvalue)
92 {
93 	struct reg regs;
94 
95 	if (phdl->status == PS_DEAD || phdl->status == PS_UNDEAD ||
96 	    phdl->status == PS_IDLE) {
97 		errno = ENOENT;
98 		return (-1);
99 	}
100 	if (ptrace(PT_GETREGS, proc_getpid(phdl), (caddr_t)&regs, 0) < 0)
101 		return (-1);
102 	switch (reg) {
103 	case REG_PC:
104 #if defined(__amd64__)
105 		regs.r_rip = regvalue;
106 #elif defined(__arm__)
107 		regs.r_pc = regvalue;
108 #elif defined(__i386__)
109 		regs.r_eip = regvalue;
110 #elif defined(__mips__)
111 		regs.r_regs[PC] = regvalue;
112 #elif defined(__powerpc__)
113 		regs.pc = regvalue;
114 #endif
115 		break;
116 	case REG_SP:
117 #if defined(__amd64__)
118 		regs.r_rsp = regvalue;
119 #elif defined(__arm__)
120 		regs.r_sp = regvalue;
121 #elif defined(__i386__)
122 		regs.r_esp = regvalue;
123 #elif defined(__mips__)
124 		regs.r_regs[PC] = regvalue;
125 #elif defined(__powerpc__)
126 		regs.fixreg[1] = regvalue;
127 #endif
128 		break;
129 	default:
130 		DPRINTFX("ERROR: no support for reg number %d", reg);
131 		return (-1);
132 	}
133 	if (ptrace(PT_SETREGS, proc_getpid(phdl), (caddr_t)&regs, 0) < 0)
134 		return (-1);
135 
136 	return (0);
137 }
138