xref: /minix3/lib/libc/gen/nlist_ecoff.c (revision f14fb602092e015ff630df58e17c2a9cd57d29b3)
1 /* $NetBSD: nlist_ecoff.c,v 1.23 2012/03/20 00:31:24 matt Exp $ */
2 
3 /*
4  * Copyright (c) 1996 Christopher G. Demetriou
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *          This product includes software developed for the
18  *          NetBSD Project.  See http://www.NetBSD.org/ for
19  *          information about NetBSD.
20  * 4. The name of the author may not be used to endorse or promote products
21  *    derived from this software without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
24  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
25  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
26  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
27  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
28  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
29  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
30  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
31  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
32  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33  *
34  * <<Id: LICENSE,v 1.2 2000/06/14 15:57:33 cgd Exp>>
35  */
36 
37 #include <sys/cdefs.h>
38 #if defined(LIBC_SCCS) && !defined(lint)
39 __RCSID("$NetBSD: nlist_ecoff.c,v 1.23 2012/03/20 00:31:24 matt Exp $");
40 #endif /* LIBC_SCCS and not lint */
41 
42 #include "namespace.h"
43 #include <sys/param.h>
44 #include <sys/mman.h>
45 #include <sys/stat.h>
46 #include <sys/file.h>
47 
48 #include <assert.h>
49 #include <errno.h>
50 #include <stdio.h>
51 #include <string.h>
52 #include <unistd.h>
53 #include <nlist.h>
54 
55 #include "nlist_private.h"
56 #ifdef NLIST_ECOFF
57 #include <sys/exec_ecoff.h>
58 #endif
59 
60 #ifdef NLIST_ECOFF
61 #define	check(off, size) \
62 	((size_t)off >= mappedsize || (size_t)(off + size) > mappedsize)
63 
64 int
__fdnlist_ecoff(int fd,struct nlist * list)65 __fdnlist_ecoff(int fd, struct nlist *list)
66 {
67 	struct nlist *p;
68 	const struct ecoff_exechdr *exechdrp;
69 	const struct ecoff_symhdr *symhdrp;
70 	const struct ecoff_extsym *esyms;
71 	struct stat st;
72 	const char *mappedfile;
73 	size_t mappedsize;
74 	u_long symhdroff, extstroff;
75 	u_int symhdrsize;
76 	int rv, nent;
77 	long i, nesyms;
78 
79 	_DIAGASSERT(fd != -1);
80 	_DIAGASSERT(list != NULL);
81 
82 	rv = -1;
83 
84 	/*
85 	 * If we can't fstat() the file, something bad is going on.
86 	 */
87 	if (fstat(fd, &st) < 0)
88 		goto out;
89 
90 	/*
91 	 * Map the file in its entirety.
92 	 */
93 	if ((uintmax_t)st.st_size > (uintmax_t)SIZE_T_MAX) {
94 		errno = EFBIG;
95 		goto out;
96 	}
97 	mappedsize = (size_t)st.st_size;
98 	mappedfile = mmap(NULL, mappedsize, PROT_READ, MAP_PRIVATE|MAP_FILE,
99 	    fd, 0);
100 	if (mappedfile == MAP_FAILED)
101 		goto out;
102 
103 	/*
104 	 * Make sure we can access the executable's header
105 	 * directly, and make sure the recognize the executable
106 	 * as an ECOFF binary.
107 	 */
108 	if (check(0, sizeof *exechdrp))
109 		goto unmap;
110 	exechdrp = (const void *)mappedfile;
111 
112 	if (ECOFF_BADMAG(exechdrp))
113 		goto unmap;
114 
115 	/*
116 	 * Find the symbol list.
117 	 */
118 	symhdroff = exechdrp->f.f_symptr;
119 	symhdrsize = exechdrp->f.f_nsyms;
120 
121 	if ((symhdroff + sizeof *symhdrp) > mappedsize ||
122 	    sizeof *symhdrp != symhdrsize)
123 		goto unmap;
124 	symhdrp = (const void *)&mappedfile[symhdroff];
125 
126 	nesyms = symhdrp->esymMax;
127 	if (check(symhdrp->cbExtOffset, nesyms * sizeof *esyms))
128 		goto unmap;
129 	esyms = (const void *)&mappedfile[symhdrp->cbExtOffset];
130 	extstroff = symhdrp->cbSsExtOffset;
131 
132 	/*
133 	 * Clean out any left-over information for all valid entries.
134 	 * Type and value are defined to be 0 if not found; historical
135 	 * versions cleared other and desc as well.
136 	 *
137 	 * XXX Clearing anything other than n_type and n_value violates
138 	 * the semantics given in the man page.
139 	 */
140 	nent = 0;
141 	for (p = list; !ISLAST(p); ++p) {
142 		p->n_type = 0;
143 		p->n_other = 0;
144 		p->n_desc = 0;
145 		p->n_value = 0;
146 		++nent;
147 	}
148 
149 	for (i = 0; i < nesyms; i++) {
150 		for (p = list; !ISLAST(p); p++) {
151 			const char *nlistname;
152 			const char *symtabname;
153 
154 			/* This may be incorrect */
155 			nlistname = N_NAME(p);
156 			if (*nlistname == '_')
157 				nlistname++;
158 
159 			symtabname =
160 			    &mappedfile[extstroff + esyms[i].es_strindex];
161 
162 			if (!strcmp(symtabname, nlistname)) {
163 				/*
164 				 * Translate (roughly) from ECOFF to nlist
165 				 */
166 				p->n_value = esyms[i].es_value;
167 				p->n_type = N_EXT;		/* XXX */
168 				p->n_desc = 0;			/* XXX */
169 				p->n_other = 0;			/* XXX */
170 
171 				if (--nent <= 0)
172 					goto done;
173 				break;	/* into next run of outer loop */
174 			}
175 		}
176 	}
177 
178 done:
179 	rv = nent;
180 unmap:
181 	munmap(__UNCONST(mappedfile), mappedsize);
182 out:
183 	return rv;
184 }
185 
186 #endif /* NLIST_ECOFF */
187