1 /*-
2  * Copyright (c) 2009 Kai Wang
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer
10  *    in this position and unchanged.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  */
26 
27 #include <sys/param.h>
28 #include <ctype.h>
29 #include <err.h>
30 #include <getopt.h>
31 #include <libelftc.h>
32 #include <stdlib.h>
33 #include <stdio.h>
34 #include <string.h>
35 
36 #include "_elftc.h"
37 
38 ELFTC_VCSID("$Id: cxxfilt.c 3356 2016-01-22 22:31:38Z jkoshy $");
39 
40 #define	STRBUFSZ	8192
41 
42 static int stripus = 0;
43 static int noparam = 0;
44 static int format = 0;
45 
46 enum options
47 {
48 	OPTION_HELP,
49 	OPTION_VERSION
50 };
51 
52 static struct option longopts[] =
53 {
54 	{"format", required_argument, NULL, 's'},
55 	{"help", no_argument, NULL, OPTION_HELP},
56 	{"no-params", no_argument, NULL, 'p'},
57 	{"no-strip-underscores", no_argument, NULL, 'n'},
58 	{"strip-underscores", no_argument, NULL, '_'},
59 	{"version", no_argument, NULL, 'V'},
60 	{NULL, 0, NULL, 0}
61 };
62 
63 static struct {
64 	const char *fname;
65 	int fvalue;
66 } flist[] = {
67 	{"auto", 0},
68 	{"arm", ELFTC_DEM_ARM},
69 	{"gnu", ELFTC_DEM_GNU2},
70 	{"gnu-v3", ELFTC_DEM_GNU3}
71 };
72 
73 #define	USAGE_MESSAGE	"\
74 Usage: %s [options] [encoded-names...]\n\
75   Translate C++ symbol names to human-readable form.\n\n\
76   Options:\n\
77   -_ | --strip-underscores     Remove leading underscores prior to decoding.\n\
78   -n | --no-strip-underscores  Do not remove leading underscores.\n\
79   -p | --no-params             (Accepted but ignored).\n\
80   -s SCHEME | --format=SCHEME  Select the encoding scheme to use.\n\
81                                Valid schemes are: 'arm', 'auto', 'gnu' and\n\
82                                'gnu-v3'.\n\
83   --help                       Print a help message.\n\
84   --version                    Print a version identifier and exit.\n"
85 
86 static void
usage(void)87 usage(void)
88 {
89 
90 	(void) fprintf(stderr, USAGE_MESSAGE, ELFTC_GETPROGNAME());
91 	exit(1);
92 }
93 
94 static void
version(void)95 version(void)
96 {
97 	fprintf(stderr, "%s (%s)\n", ELFTC_GETPROGNAME(), elftc_version());
98 	exit(0);
99 }
100 
101 static int
find_format(const char * fstr)102 find_format(const char *fstr)
103 {
104 	int i;
105 
106 	for (i = 0; (size_t) i < sizeof(flist) / sizeof(flist[0]); i++) {
107 		if (!strcmp(fstr, flist[i].fname))
108 		    return (flist[i].fvalue);
109 	}
110 
111 	return (-1);
112 }
113 
114 static char *
demangle(char * name,int strict,size_t * pos)115 demangle(char *name, int strict, size_t *pos)
116 {
117 	static char dem[STRBUFSZ];
118 	char nb[STRBUFSZ];
119 	size_t p, t;
120 
121 	if (stripus && *name == '_') {
122 		strncpy(nb, name + 1, sizeof(nb) - 1);
123 		t = 1;
124 	} else {
125 		strncpy(nb, name, sizeof(nb) - 1);
126 		t = 0;
127 	}
128 	nb[sizeof(nb) - 1] = '\0';
129 
130 	p = strlen(nb);
131 	if (p == 0)
132 		return NULL;
133 
134 	while (elftc_demangle(nb, dem, sizeof(dem), (unsigned) format) < 0) {
135 		if (!strict && p > 1) {
136 			nb[--p] = '\0';
137 			continue;
138 		} else
139 			return (NULL);
140 	}
141 
142 	if (pos != NULL)
143 		*pos = t ? p + 1 : p;
144 
145 	return (dem);
146 }
147 
148 int
main(int argc,char ** argv)149 main(int argc, char **argv)
150 {
151 	char *dem, buf[STRBUFSZ];
152 	size_t i, p, s;
153 	int c, n, opt;
154 
155 	while ((opt = getopt_long(argc, argv, "_nps:V", longopts, NULL)) !=
156 	    -1) {
157 		switch (opt) {
158 		case '_':
159 			stripus = 1;
160 			break;
161 		case 'n':
162 			stripus = 0;
163 			break;
164 		case 'p':
165 			noparam = 1;
166 			break;
167 		case 's':
168 			if ((format = find_format(optarg)) < 0)
169 				errx(EXIT_FAILURE, "unsupported format: %s",
170 				    optarg);
171 			break;
172 		case 'V':
173 			version();
174 			/* NOT REACHED */
175 		case OPTION_HELP:
176 		default:
177 			usage();
178 			/* NOT REACHED */
179 		}
180 	}
181 
182 	argv += optind;
183 	argc -= optind;
184 
185 	if (*argv != NULL) {
186 		for (n = 0; n < argc; n++) {
187 			if ((dem = demangle(argv[n], 1, NULL)) == NULL)
188 				fprintf(stderr, "Failed: %s\n", argv[n]);
189 			else
190 				printf("%s\n", dem);
191 		}
192 	} else {
193 		p = 0;
194 		for (;;) {
195 			c = fgetc(stdin);
196 			if (c == EOF || !isprint(c) || strchr(" \t\n", c)) {
197 				if (p > 0) {
198 					buf[p] = '\0';
199 					if ((dem = demangle(buf, 0, &s)) ==
200 					    NULL)
201 						printf("%s", buf);
202 					else {
203 						printf("%s", dem);
204 						for (i = s; i < p; i++)
205 							putchar(buf[i]);
206 					}
207 					p = 0;
208 				}
209 				if (c == EOF)
210 					break;
211 				if (isprint(c) || strchr(" \t\n", c))
212 					putchar(c);
213 			} else {
214 				if ((size_t) p >= sizeof(buf) - 1)
215 					warnx("buffer overflowed");
216 				else
217 					buf[p++] = (char) c;
218 			}
219 
220 		}
221 	}
222 
223 	exit(0);
224 }
225