1 /* Test program for CFI handling.
2 Copyright (C) 2009-2010, 2013, 2015 Red Hat, Inc.
3 This file is part of elfutils.
4
5 This file is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 3 of the License, or
8 (at your option) any later version.
9
10 elfutils 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
13 GNU 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, see <http://www.gnu.org/licenses/>. */
17
18 #include <config.h>
19 #include <assert.h>
20 #include <inttypes.h>
21 #include ELFUTILS_HEADER(dwfl)
22 #include <dwarf.h>
23 #include <argp.h>
24 #include <stdio.h>
25 #include <stdio_ext.h>
26 #include <locale.h>
27 #include <stdlib.h>
28 #include <string.h>
29
30 #include "../libdw/known-dwarf.h"
31
32 static const char *
op_name(unsigned int code)33 op_name (unsigned int code)
34 {
35 static const char *const known[] =
36 {
37 #define DWARF_ONE_KNOWN_DW_OP(NAME, CODE) [CODE] = #NAME,
38 DWARF_ALL_KNOWN_DW_OP
39 #undef DWARF_ONE_KNOWN_DW_OP
40 };
41
42 if (likely (code < sizeof (known) / sizeof (known[0])))
43 return known[code];
44
45 return NULL;
46 }
47
48 static void
print_detail(int result,const Dwarf_Op * ops,size_t nops,Dwarf_Addr bias)49 print_detail (int result, const Dwarf_Op *ops, size_t nops, Dwarf_Addr bias)
50 {
51 if (result < 0)
52 printf ("indeterminate (%s)\n", dwarf_errmsg (-1));
53 else if (nops == 0)
54 printf ("%s\n", ops == NULL ? "same_value" : "undefined");
55 else
56 {
57 printf ("%s expression:", result == 0 ? "location" : "value");
58 for (size_t i = 0; i < nops; ++i)
59 {
60 printf (" %s", op_name(ops[i].atom));
61 if (ops[i].number2 == 0)
62 {
63 if (ops[i].atom == DW_OP_addr)
64 printf ("(%#" PRIx64 ")", ops[i].number + bias);
65 else if (ops[i].number != 0)
66 printf ("(%" PRId64 ")", ops[i].number);
67 }
68 else
69 printf ("(%" PRId64 ",%" PRId64 ")",
70 ops[i].number, ops[i].number2);
71 }
72 puts ("");
73 }
74 }
75
76 struct stuff
77 {
78 Dwarf_Frame *frame;
79 Dwarf_Addr bias;
80 };
81
82 static int
print_register(void * arg,int regno,const char * setname,const char * prefix,const char * regname,int bits,int type)83 print_register (void *arg,
84 int regno,
85 const char *setname,
86 const char *prefix,
87 const char *regname,
88 int bits __attribute__ ((unused)),
89 int type __attribute__ ((unused)))
90 {
91 struct stuff *stuff = arg;
92
93 printf ("\t%s reg%u (%s%s): ", setname, regno, prefix, regname);
94
95 Dwarf_Op ops_mem[2];
96 Dwarf_Op *ops;
97 size_t nops;
98 int result = dwarf_frame_register (stuff->frame, regno, ops_mem, &ops, &nops);
99 print_detail (result, ops, nops, stuff->bias);
100
101 return DWARF_CB_OK;
102 }
103
104 static int
handle_cfi(Dwfl * dwfl,const char * which,Dwarf_CFI * cfi,GElf_Addr pc,struct stuff * stuff)105 handle_cfi (Dwfl *dwfl, const char *which, Dwarf_CFI *cfi,
106 GElf_Addr pc, struct stuff *stuff)
107 {
108 if (cfi == NULL)
109 {
110 printf ("handle_cfi no CFI (%s): %s\n", which, dwarf_errmsg (-1));
111 return -1;
112 }
113
114 int result = dwarf_cfi_addrframe (cfi, pc - stuff->bias, &stuff->frame);
115 if (result != 0)
116 {
117 printf ("dwarf_cfi_addrframe (%s): %s\n", which, dwarf_errmsg (-1));
118 return 1;
119 }
120
121 Dwarf_Addr start = pc;
122 Dwarf_Addr end = pc;
123 bool signalp;
124 int ra_regno = dwarf_frame_info (stuff->frame, &start, &end, &signalp);
125 if (ra_regno >= 0)
126 {
127 start += stuff->bias;
128 end += stuff->bias;
129 }
130
131 printf ("%s has %#" PRIx64 " => [%#" PRIx64 ", %#" PRIx64 "):\n",
132 which, pc, start, end);
133
134 if (ra_regno < 0)
135 printf ("\treturn address register unavailable (%s)\n",
136 dwarf_errmsg (0));
137 else
138 printf ("\treturn address in reg%u%s\n",
139 ra_regno, signalp ? " (signal frame)" : "");
140
141 // Point cfa_ops to dummy to match print_detail expectations.
142 // (nops == 0 && cfa_ops != NULL => "undefined")
143 Dwarf_Op dummy;
144 Dwarf_Op *cfa_ops = &dummy;
145 size_t cfa_nops;
146 result = dwarf_frame_cfa (stuff->frame, &cfa_ops, &cfa_nops);
147
148 printf ("\tCFA ");
149 print_detail (result, cfa_ops, cfa_nops, stuff->bias);
150
151 (void) dwfl_module_register_names (dwfl_addrmodule (dwfl, pc),
152 &print_register, stuff);
153
154 return 0;
155 }
156
157 static int
handle_address(GElf_Addr pc,Dwfl * dwfl)158 handle_address (GElf_Addr pc, Dwfl *dwfl)
159 {
160 Dwfl_Module *mod = dwfl_addrmodule (dwfl, pc);
161
162 struct stuff stuff;
163 stuff.frame = NULL;
164 stuff.bias = 0;
165 int res = handle_cfi (dwfl, ".eh_frame",
166 dwfl_module_eh_cfi (mod, &stuff.bias), pc, &stuff);
167 free (stuff.frame);
168
169 stuff.frame = NULL;
170 stuff.bias = 0;
171 res &= handle_cfi (dwfl, ".debug_frame",
172 dwfl_module_dwarf_cfi (mod, &stuff.bias), pc, &stuff);
173 free (stuff.frame);
174
175 return res;
176 }
177
178 int
main(int argc,char * argv[])179 main (int argc, char *argv[])
180 {
181 int remaining;
182
183 /* Set locale. */
184 (void) setlocale (LC_ALL, "");
185
186 Dwfl *dwfl = NULL;
187 (void) argp_parse (dwfl_standard_argp (), argc, argv, 0, &remaining, &dwfl);
188 assert (dwfl != NULL);
189
190 int result = 0;
191
192 /* Now handle the addresses. In case none are given on the command
193 line, read from stdin. */
194 if (remaining == argc)
195 {
196 /* We use no threads here which can interfere with handling a stream. */
197 (void) __fsetlocking (stdin, FSETLOCKING_BYCALLER);
198
199 char *buf = NULL;
200 size_t len = 0;
201 while (!feof_unlocked (stdin))
202 {
203 if (getline (&buf, &len, stdin) < 0)
204 break;
205
206 char *endp;
207 uintmax_t addr = strtoumax (buf, &endp, 0);
208 if (endp != buf)
209 result |= handle_address (addr, dwfl);
210 else
211 result = 1;
212 }
213
214 free (buf);
215 }
216 else
217 {
218 do
219 {
220 char *endp;
221 uintmax_t addr = strtoumax (argv[remaining], &endp, 0);
222 if (endp != argv[remaining])
223 result |= handle_address (addr, dwfl);
224 else
225 result = 1;
226 }
227 while (++remaining < argc);
228 }
229
230 dwfl_end (dwfl);
231
232 return result;
233 }
234