dmake: do not set MAKEFLAGS=k
[unleashed/tickless.git] / usr / src / cmd / boot / symdef / symdef.c
blob4a0ddbc1a13cd3a768fac5fbfdc228e1503b9748
1 /*
2 * CDDL HEADER START
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
19 * CDDL HEADER END
23 * Copyright 2007 Sun Microsystems, Inc. All rights reserved.
24 * Use is subject to license terms.
27 #pragma ident "%Z%%M% %I% %E% SMI"
29 #include <stdio.h>
30 #include <string.h>
31 #include <sys/types.h>
32 #include <sys/stat.h>
33 #include <fcntl.h>
34 #include <unistd.h>
35 #include <libelf.h>
36 #include <gelf.h>
37 #include <errno.h>
40 * symdef is a very simplified version of nm. It is used by upgrade and
41 * create_ramdisk in situations where we can't guarantee that nm will be around.
43 * Two arguments are expected: a binary and a symbol name. If the symbol is
44 * found in the name table of the binary, 0 is returned. If it is not found,
45 * 1 is returned. If an error occurs, a message is printed to stderr and -1
46 * is returned.
50 static void
51 usage(void)
53 (void) fprintf(stderr, "USAGE: symdef file_name symbol\n");
56 int
57 main(int argc, char *argv[])
59 int fd = 0;
60 int rv = 1;
61 uint_t cnt, symcnt;
62 Elf *elfp = NULL;
63 Elf_Scn *scn = NULL;
64 size_t shstrndx;
65 GElf_Ehdr ehdr;
66 GElf_Shdr shdr;
67 GElf_Sym sym;
68 Elf32_Word shndx;
69 Elf_Data *symdata, *shndxdata;
71 if (argc != 3) {
72 usage();
73 return (-1);
76 fd = open(argv[1], O_RDONLY);
77 if (fd == -1) {
78 (void) fprintf(stderr, "%s\n", strerror(errno));
79 rv = -1;
80 goto done;
82 if (elf_version(EV_CURRENT) == EV_NONE) {
83 (void) fprintf(stderr, "Elf library version out of date\n");
84 rv = -1;
85 goto done;
87 elfp = elf_begin(fd, ELF_C_READ, NULL);
88 if ((elfp == NULL) || (elf_kind(elfp) != ELF_K_ELF) ||
89 ((gelf_getehdr(elfp, &ehdr)) == NULL) ||
90 (elf_getshstrndx(elfp, &shstrndx) == 0))
91 goto done;
93 while ((scn = elf_nextscn(elfp, scn)) != NULL) {
94 if ((gelf_getshdr(scn, &shdr) == NULL) ||
95 ((shdr.sh_type != SHT_SYMTAB) &&
96 (shdr.sh_type != SHT_DYNSYM)) ||
97 ((symdata = elf_getdata(scn, NULL)) == NULL))
98 continue;
99 symcnt = shdr.sh_size / shdr.sh_entsize;
100 shndxdata = NULL;
101 for (cnt = 0; cnt < symcnt; cnt++) {
102 if ((gelf_getsymshndx(symdata, shndxdata, cnt,
103 &sym, &shndx) != NULL) &&
104 (strcmp(argv[2], elf_strptr(elfp, shdr.sh_link,
105 sym.st_name)) == 0)) {
106 rv = 0;
107 goto done;
111 done:
112 if (elfp)
113 (void) elf_end(elfp);
114 if (fd != -1)
115 (void) close(fd);
116 return (rv);