xref: /netbsd-src/lib/libc/gen/nlist_ecoff.c (revision d896261208b4610b0c4e86ea95caad3cdc86a4ac)
1 /*	$NetBSD: nlist_ecoff.c,v 1.10 1999/09/20 04:39:03 lukem Exp $	*/
2 
3 /*
4  * Copyright (c) 1996 Christopher G. Demetriou.  All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
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  * 3. All advertising materials mentioning features or use of this software
15  *    must display the following acknowledgement:
16  *      This product includes software developed by Christopher G. Demetriou
17  *	for the NetBSD Project.
18  * 4. The name of the author may not be used to endorse or promote products
19  *    derived from this software without specific prior written permission
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 #include <sys/cdefs.h>
34 #if defined(LIBC_SCCS) && !defined(lint)
35 __RCSID("$NetBSD: nlist_ecoff.c,v 1.10 1999/09/20 04:39:03 lukem Exp $");
36 #endif /* LIBC_SCCS and not lint */
37 
38 #include "namespace.h"
39 #include <sys/param.h>
40 #include <sys/mman.h>
41 #include <sys/stat.h>
42 #include <sys/file.h>
43 
44 #include <assert.h>
45 #include <errno.h>
46 #include <stdio.h>
47 #include <string.h>
48 #include <unistd.h>
49 #include <a.out.h>			/* for 'struct nlist' declaration */
50 
51 #include "nlist_private.h"
52 #ifdef NLIST_ECOFF
53 #include <sys/exec_ecoff.h>
54 #endif
55 
56 #ifdef NLIST_ECOFF
57 #define	check(off, size)	((off < 0) || (off + size > mappedsize))
58 #define	BAD			do { rv = -1; goto out; } while (0)
59 #define	BADUNMAP		do { rv = -1; goto unmap; } while (0)
60 
61 int
62 __fdnlist_ecoff(fd, list)
63 	int fd;
64 	struct nlist *list;
65 {
66 	struct nlist *p;
67 	struct ecoff_exechdr *exechdrp;
68 	struct ecoff_symhdr *symhdrp;
69 	struct ecoff_extsym *esyms;
70 	struct stat st;
71 	char *mappedfile;
72 	size_t mappedsize;
73 	u_long symhdroff, extstroff;
74 	u_int symhdrsize;
75 	int rv, nent;
76 	long i, nesyms;
77 
78 	_DIAGASSERT(fd != -1);
79 	_DIAGASSERT(list != NULL);
80 
81 	rv = -1;
82 
83 	/*
84 	 * If we can't fstat() the file, something bad is going on.
85 	 */
86 	if (fstat(fd, &st) < 0)
87 		BAD;
88 
89 	/*
90 	 * Map the file in its entirety.
91 	 */
92 	if (st.st_size > SIZE_T_MAX) {
93 		errno = EFBIG;
94 		BAD;
95 	}
96 	mappedsize = st.st_size;
97 	mappedfile = mmap(NULL, mappedsize, PROT_READ, MAP_PRIVATE|MAP_FILE,
98 	    fd, 0);
99 	if (mappedfile == (char *)-1)
100 		BAD;
101 
102 	/*
103 	 * Make sure we can access the executable's header
104 	 * directly, and make sure the recognize the executable
105 	 * as an ECOFF binary.
106 	 */
107 	if (check(0, sizeof *exechdrp))
108 		BADUNMAP;
109 	exechdrp = (struct ecoff_exechdr *)&mappedfile[0];
110 
111 	if (ECOFF_BADMAG(exechdrp))
112 		BADUNMAP;
113 
114 	/*
115 	 * Find the symbol list.
116 	 */
117 	symhdroff = exechdrp->f.f_symptr;
118 	symhdrsize = exechdrp->f.f_nsyms;
119 
120 	if (check(symhdroff, sizeof *symhdrp) ||
121 	    sizeof *symhdrp != symhdrsize)
122 		BADUNMAP;
123 	symhdrp = (struct ecoff_symhdr *)&mappedfile[symhdroff];
124 
125 	nesyms = symhdrp->esymMax;
126 	if (check(symhdrp->cbExtOffset, nesyms * sizeof *esyms))
127 		BADUNMAP;
128 	esyms = (struct ecoff_extsym *)&mappedfile[symhdrp->cbExtOffset];
129 	extstroff = symhdrp->cbSsExtOffset;
130 
131 	/*
132 	 * Clean out any left-over information for all valid entries.
133 	 * Type and value are defined to be 0 if not found; historical
134 	 * versions cleared other and desc as well.
135 	 *
136 	 * XXX Clearing anything other than n_type and n_value violates
137 	 * the semantics given in the man page.
138 	 */
139 	nent = 0;
140 	for (p = list; !ISLAST(p); ++p) {
141 		p->n_type = 0;
142 		p->n_other = 0;
143 		p->n_desc = 0;
144 		p->n_value = 0;
145 		++nent;
146 	}
147 
148 	for (i = 0; i < nesyms; i++) {
149 		for (p = list; !ISLAST(p); p++) {
150 			char *nlistname;
151 			char *symtabname;
152 
153 			/* This may be incorrect */
154 			nlistname = p->n_un.n_name;
155 			if (*nlistname == '_')
156 				nlistname++;
157 
158 			symtabname =
159 			    &mappedfile[extstroff + esyms[i].es_strindex];
160 
161 			if (!strcmp(symtabname, nlistname)) {
162 				/*
163 				 * Translate (roughly) from ECOFF to nlist
164 				 */
165 				p->n_value = esyms[i].es_value;
166 				p->n_type = N_EXT;		/* XXX */
167 				p->n_desc = 0;			/* XXX */
168 				p->n_other = 0;			/* XXX */
169 
170 				if (--nent <= 0)
171 					goto done;
172 				break;	/* into next run of outer loop */
173 			}
174 		}
175 	}
176 
177 done:
178 	rv = nent;
179 unmap:
180 	munmap(mappedfile, mappedsize);
181 out:
182 	return (rv);
183 }
184 
185 #endif /* NLIST_ECOFF */
186