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/*
* Copyright (c) 1989, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)nlist.c 8.1 (Berkeley) 6/4/93";
#endif /* LIBC_SCCS and not lint */
#include <sys/param.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/file.h>
#include <errno.h>
#include <a.out.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
int
nlist(name, list)
const char *name;
struct nlist *list;
{
int fd, n;
fd = open(name, O_RDONLY, 0);
if (fd < 0)
return (-1);
n = __fdnlist(fd, list);
(void)close(fd);
return (n);
}
#define ISLAST(p) (p->n_un.n_name == 0 || p->n_un.n_name[0] == 0)
int
__fdnlist(fd, list)
register int fd;
register struct nlist *list;
{
register struct nlist *p, *s;
register caddr_t strtab;
register off_t stroff, symoff;
register u_long symsize;
register int nent, cc;
size_t strsize;
struct nlist nbuf[1024];
struct exec exec;
struct stat st;
if (lseek(fd, (off_t)0, SEEK_SET) == -1 ||
read(fd, &exec, sizeof(exec)) != sizeof(exec) ||
N_BADMAG(exec) || fstat(fd, &st) < 0)
return (-1);
symoff = N_SYMOFF(exec);
symsize = exec.a_syms;
stroff = symoff + symsize;
/* Check for files too large to mmap. */
if (st.st_size - stroff > SIZE_T_MAX) {
errno = EFBIG;
return (-1);
}
/*
* Map string table into our address space. This gives us
* an easy way to randomly access all the strings, without
* making the memory allocation permanent as with malloc/free
* (i.e., munmap will return it to the system).
*/
strsize = st.st_size - stroff;
strtab = mmap(NULL, (size_t)strsize, PROT_READ, 0, fd, stroff);
if (strtab == (char *)-1)
return (-1);
/*
* clean out any left-over information for all valid entries.
* Type and value defined to be 0 if not found; historical
* versions cleared other and desc as well. Also figure out
* the largest string length so don't read any more of the
* string table than we have to.
*
* XXX clearing anything other than n_type and n_value violates
* the semantics given in the man page.
*/
nent = 0;
for (p = list; !ISLAST(p); ++p) {
p->n_type = 0;
p->n_other = 0;
p->n_desc = 0;
p->n_value = 0;
++nent;
}
if (lseek(fd, symoff, SEEK_SET) == -1)
return (-1);
while (symsize > 0) {
cc = MIN(symsize, sizeof(nbuf));
if (read(fd, nbuf, cc) != cc)
break;
symsize -= cc;
for (s = nbuf; cc > 0; ++s, cc -= sizeof(*s)) {
register int soff = s->n_un.n_strx;
if (soff == 0 || (s->n_type & N_STAB) != 0)
continue;
for (p = list; !ISLAST(p); p++)
if (!strcmp(&strtab[soff], p->n_un.n_name)) {
p->n_value = s->n_value;
p->n_type = s->n_type;
p->n_desc = s->n_desc;
p->n_other = s->n_other;
if (--nent <= 0)
break;
}
}
}
munmap(strtab, strsize);
return (nent);
}
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