xref: /titanic_52/usr/src/lib/libdisasm/common/libdisasm.c (revision fca4268092e9961ebb9b5e0098dcebc545023586)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  * Copyright 2012 Joshua M. Clulow <josh@sysmgr.org>
26  * Copyright 2015 Nexenta Systems, Inc.  All rights reserved.
27  */
28 
29 #include <libdisasm.h>
30 #include <stdlib.h>
31 #ifdef DIS_STANDALONE
32 #include <mdb/mdb_modapi.h>
33 #define	_MDB
34 #include <mdb/mdb_io.h>
35 #else
36 #include <stdio.h>
37 #endif
38 
39 #include "libdisasm_impl.h"
40 
41 static int _dis_errno;
42 
43 /*
44  * If we're building the standalone library, then we only want to
45  * include support for disassembly of the native architecture.
46  * The regular shared library should include support for all
47  * architectures.
48  */
49 #if !defined(DIS_STANDALONE) || defined(__i386) || defined(__amd64)
50 extern dis_arch_t dis_arch_i386;
51 #endif
52 #if !defined(DIS_STANDALONE) || defined(__sparc)
53 extern dis_arch_t dis_arch_sparc;
54 #endif
55 
56 static dis_arch_t *dis_archs[] = {
57 #if !defined(DIS_STANDALONE) || defined(__i386) || defined(__amd64)
58 	&dis_arch_i386,
59 #endif
60 #if !defined(DIS_STANDALONE) || defined(__sparc)
61 	&dis_arch_sparc,
62 #endif
63 	NULL
64 };
65 
66 /*
67  * For the standalone library, we need to link against mdb's malloc/free.
68  * Otherwise, use the standard malloc/free.
69  */
70 #ifdef DIS_STANDALONE
71 void *
72 dis_zalloc(size_t bytes)
73 {
74 	return (mdb_zalloc(bytes, UM_SLEEP));
75 }
76 
77 void
78 dis_free(void *ptr, size_t bytes)
79 {
80 	mdb_free(ptr, bytes);
81 }
82 #else
83 void *
84 dis_zalloc(size_t bytes)
85 {
86 	return (calloc(1, bytes));
87 }
88 
89 /*ARGSUSED*/
90 void
91 dis_free(void *ptr, size_t bytes)
92 {
93 	free(ptr);
94 }
95 #endif
96 
97 int
98 dis_seterrno(int error)
99 {
100 	_dis_errno = error;
101 	return (-1);
102 }
103 
104 int
105 dis_errno(void)
106 {
107 	return (_dis_errno);
108 }
109 
110 const char *
111 dis_strerror(int error)
112 {
113 	switch (error) {
114 	case E_DIS_NOMEM:
115 		return ("out of memory");
116 	case E_DIS_INVALFLAG:
117 		return ("invalid flags for this architecture");
118 	case E_DIS_UNSUPARCH:
119 		return ("unsupported machine architecture");
120 	default:
121 		return ("unknown error");
122 	}
123 }
124 
125 void
126 dis_set_data(dis_handle_t *dhp, void *data)
127 {
128 	dhp->dh_data = data;
129 }
130 
131 void
132 dis_flags_set(dis_handle_t *dhp, int f)
133 {
134 	dhp->dh_flags |= f;
135 }
136 
137 void
138 dis_flags_clear(dis_handle_t *dhp, int f)
139 {
140 	dhp->dh_flags &= ~f;
141 }
142 
143 void
144 dis_handle_destroy(dis_handle_t *dhp)
145 {
146 	dhp->dh_arch->da_handle_detach(dhp);
147 	dis_free(dhp, sizeof (dis_handle_t));
148 }
149 
150 dis_handle_t *
151 dis_handle_create(int flags, void *data, dis_lookup_f lookup_func,
152     dis_read_f read_func)
153 {
154 	dis_handle_t *dhp;
155 	dis_arch_t *arch = NULL;
156 	int i;
157 
158 	/* Select an architecture based on flags */
159 	for (i = 0; dis_archs[i] != NULL; i++) {
160 		if (dis_archs[i]->da_supports_flags(flags)) {
161 			arch = dis_archs[i];
162 			break;
163 		}
164 	}
165 	if (arch == NULL) {
166 		(void) dis_seterrno(E_DIS_UNSUPARCH);
167 		return (NULL);
168 	}
169 
170 	if ((dhp = dis_zalloc(sizeof (dis_handle_t))) == NULL) {
171 		(void) dis_seterrno(E_DIS_NOMEM);
172 		return (NULL);
173 	}
174 	dhp->dh_arch = arch;
175 	dhp->dh_lookup = lookup_func;
176 	dhp->dh_read = read_func;
177 	dhp->dh_flags = flags;
178 	dhp->dh_data = data;
179 
180 	/*
181 	 * Allow the architecture-specific code to allocate
182 	 * its private data.
183 	 */
184 	if (arch->da_handle_attach(dhp) != 0) {
185 		dis_free(dhp, sizeof (dis_handle_t));
186 		/* dis errno already set */
187 		return (NULL);
188 	}
189 
190 	return (dhp);
191 }
192 
193 int
194 dis_disassemble(dis_handle_t *dhp, uint64_t addr, char *buf, size_t buflen)
195 {
196 	return (dhp->dh_arch->da_disassemble(dhp, addr, buf, buflen));
197 }
198 
199 uint64_t
200 dis_previnstr(dis_handle_t *dhp, uint64_t pc, int n)
201 {
202 	return (dhp->dh_arch->da_previnstr(dhp, pc, n));
203 }
204 
205 int
206 dis_min_instrlen(dis_handle_t *dhp)
207 {
208 	return (dhp->dh_arch->da_min_instrlen(dhp));
209 }
210 
211 int
212 dis_max_instrlen(dis_handle_t *dhp)
213 {
214 	return (dhp->dh_arch->da_max_instrlen(dhp));
215 }
216 
217 int
218 dis_instrlen(dis_handle_t *dhp, uint64_t pc)
219 {
220 	return (dhp->dh_arch->da_instrlen(dhp, pc));
221 }
222 
223 int
224 dis_vsnprintf(char *restrict s, size_t n, const char *restrict format,
225     va_list args)
226 {
227 #ifdef DIS_STANDALONE
228 	return (mdb_iob_vsnprintf(s, n, format, args));
229 #else
230 	return (vsnprintf(s, n, format, args));
231 #endif
232 }
233 
234 int
235 dis_snprintf(char *restrict s, size_t n, const char *restrict format, ...)
236 {
237 	va_list args;
238 
239 	va_start(args, format);
240 	n = dis_vsnprintf(s, n, format, args);
241 	va_end(args);
242 
243 	return (n);
244 }
245