1 files changed, 117 insertions, 0 deletions
diff --git a/usr/src/cmd/boot/symdef/symdef.c b/usr/src/cmd/boot/symdef/symdef.c
new file mode 100644
index 0000000000..4a0ddbc1a1
--- /dev/null
+++ b/usr/src/cmd/boot/symdef/symdef.c
@@ -0,0 +1,117 @@
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License (the "License").
+ * You may not use this file except in compliance with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ */
+
+/*
+ * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
+ * Use is subject to license terms.
+ */
+
+#pragma ident	"%Z%%M%	%I%	%E% SMI"
+
+#include <stdio.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <libelf.h>
+#include <gelf.h>
+#include <errno.h>
+
+/*
+ * symdef is a very simplified version of nm.  It is used by upgrade and
+ * create_ramdisk in situations where we can't guarantee that nm will be around.
+ *
+ * Two arguments are expected: a binary and a symbol name.  If the symbol is
+ * found in the name table of the binary, 0 is returned.  If it is not found,
+ * 1 is returned.  If an error occurs, a message is printed to stderr and -1
+ * is returned.
+ */
+
+
+static void
+usage(void)
+{
+	(void) fprintf(stderr, "USAGE: symdef file_name symbol\n");
+}
+
+int
+main(int argc, char *argv[])
+{
+	int	fd = 0;
+	int	rv = 1;
+	uint_t	cnt, symcnt;
+	Elf	*elfp = NULL;
+	Elf_Scn	*scn = NULL;
+	size_t	shstrndx;
+	GElf_Ehdr	ehdr;
+	GElf_Shdr	shdr;
+	GElf_Sym	sym;
+	Elf32_Word	shndx;
+	Elf_Data	*symdata, *shndxdata;
+
+	if (argc != 3) {
+		usage();
+		return (-1);
+	}
+
+	fd = open(argv[1], O_RDONLY);
+	if (fd == -1) {
+		(void) fprintf(stderr, "%s\n", strerror(errno));
+		rv = -1;
+		goto done;
+	}
+	if (elf_version(EV_CURRENT) == EV_NONE) {
+		(void) fprintf(stderr, "Elf library version out of date\n");
+		rv = -1;
+		goto done;
+	}
+	elfp = elf_begin(fd, ELF_C_READ, NULL);
+	if ((elfp == NULL) || (elf_kind(elfp) != ELF_K_ELF) ||
+	    ((gelf_getehdr(elfp, &ehdr)) == NULL) ||
+	    (elf_getshstrndx(elfp, &shstrndx) == 0))
+		goto done;
+
+	while ((scn = elf_nextscn(elfp, scn)) != NULL) {
+		if ((gelf_getshdr(scn, &shdr) == NULL) ||
+		    ((shdr.sh_type != SHT_SYMTAB) &&
+		    (shdr.sh_type != SHT_DYNSYM)) ||
+		    ((symdata = elf_getdata(scn, NULL)) == NULL))
+			continue;
+		symcnt = shdr.sh_size / shdr.sh_entsize;
+		shndxdata = NULL;
+		for (cnt = 0; cnt < symcnt; cnt++) {
+			if ((gelf_getsymshndx(symdata, shndxdata, cnt,
+			    &sym, &shndx) != NULL) &&
+			    (strcmp(argv[2], elf_strptr(elfp, shdr.sh_link,
+			    sym.st_name)) == 0)) {
+				rv = 0;
+				goto done;
+			}
+		}
+	}
+done:
+	if (elfp)
+		(void) elf_end(elfp);
+	if (fd != -1)
+		(void) close(fd);
+	return (rv);
+}