diff options
Diffstat (limited to 'lib/libc/gen/nlist.c')
| -rw-r--r-- | lib/libc/gen/nlist.c | 149 |
1 files changed, 149 insertions, 0 deletions
diff --git a/lib/libc/gen/nlist.c b/lib/libc/gen/nlist.c new file mode 100644 index 0000000..874f26e --- /dev/null +++ b/lib/libc/gen/nlist.c @@ -0,0 +1,149 @@ +/* + * 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); +} |
