Bring in geom(8) utility. It is an universal utility for operating on

GEOM classes. It works by loading a shared library via dlopen(3) mechanism
with class-specific code, it is also responsible for communicating with
GEOM via libgeom(3).
Per-class shared libraries are going to be stored in /lib/geom/ directory.
It provides also few standard commands like 'list', 'load' and 'unload'
for existing classes which aren't aware of geom(8).
More info will be send on freebsd-current@ mailing list.

Supported by:	Wheel - Open Technologies - http://www.wheel.pl

9 files changed, 1146 insertions, 0 deletions

diff --git a/sbin/geom/Makefile b/sbin/geom/Makefile
new file mode 100644
index 0000000..95f00d9
--- /dev/null
+++ b/sbin/geom/Makefile
@@ -0,0 +1,5 @@
+# $FreeBSD$
+
+SUBDIR=	core class
+
+.include <bsd.subdir.mk>
diff --git a/sbin/geom/Makefile.inc b/sbin/geom/Makefile.inc
new file mode 100644
index 0000000..7803210
--- /dev/null
+++ b/sbin/geom/Makefile.inc
@@ -0,0 +1,5 @@
+# $FreeBSD$
+
+BINDIR?=/sbin
+LIBDIR?=/lib/geom
+WARNS?=	6
diff --git a/sbin/geom/class/Makefile b/sbin/geom/class/Makefile
new file mode 100644
index 0000000..71edcf7
--- /dev/null
+++ b/sbin/geom/class/Makefile
@@ -0,0 +1,7 @@
+# $FreeBSD$
+
+SUBDIR=	concat
+SUBDIR+=nop
+SUBDIR+=stripe
+
+.include <bsd.subdir.mk>
diff --git a/sbin/geom/class/Makefile.inc b/sbin/geom/class/Makefile.inc
new file mode 100644
index 0000000..b927bca
--- /dev/null
+++ b/sbin/geom/class/Makefile.inc
@@ -0,0 +1,12 @@
+# $FreeBSD$
+
+.include "../Makefile.inc"
+
+SHLIB_MAJOR=1
+
+SRCS=   geom_${CLASS}.c subr.c
+SHLIB_NAME?=geom_${CLASS}.so.${SHLIB_MAJOR}
+LINKS=  ${BINDIR}/geom ${BINDIR}/g${CLASS}
+MAN=	g${CLASS}.8
+
+CFLAGS+=-I${.CURDIR}/../..
diff --git a/sbin/geom/core/Makefile b/sbin/geom/core/Makefile
new file mode 100644
index 0000000..3c37342
--- /dev/null
+++ b/sbin/geom/core/Makefile
@@ -0,0 +1,15 @@
+# $FreeBSD$
+
+.PATH:	${.CURDIR}/../misc
+
+PROG=	geom
+SRCS=	geom.c subr.c
+#MAN=	geom.8
+NOMAN=	notyet
+DPADD=	${LIBGEOM} ${LIBSBUF} ${LIBBSDXML}
+LDADD=	-lgeom -lsbuf -lbsdxml
+WARNS?=	6
+CFLAGS+=-I${.CURDIR}/../../../sys -I${.CURDIR} -I${.CURDIR}/..
+CFLAGS+=-DCLASSDIR=\"${LIBDIR}\"
+
+.include <bsd.prog.mk>
diff --git a/sbin/geom/core/geom.c b/sbin/geom/core/geom.c
new file mode 100644
index 0000000..613eb41
--- /dev/null
+++ b/sbin/geom/core/geom.c
@@ -0,0 +1,755 @@
+/*-
+ * Copyright (c) 2004 Pawel Jakub Dawidek <pjd@FreeBSD.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+#include <sys/linker.h>
+#include <sys/module.h>
+#include <sys/stat.h>
+#include <sys/sysctl.h>
+#include <ctype.h>
+#include <err.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdarg.h>
+#include <stdint.h>
+#include <string.h>
+#include <unistd.h>
+#include <libgen.h>
+#include <inttypes.h>
+#include <dlfcn.h>
+#include <assert.h>
+#include <libgeom.h>
+#include <geom.h>
+
+#include "misc/subr.h"
+
+
+static char comm[MAXPATHLEN], *class_name = NULL, *gclass_name = NULL;
+static uint32_t *version = NULL;
+static int verbose = 0;
+static struct g_command *class_commands = NULL;
+static void (*usage)(const char *name);
+
+static struct g_command *find_command(const char *cmdstr, int all);
+static int std_available(const char *name);
+
+static void std_list(struct gctl_req *req, unsigned flags);
+static void std_load(struct gctl_req *req, unsigned flags);
+static void std_unload(struct gctl_req *req, unsigned flags);
+
+struct g_command std_commands[] = {
+	{ "list", 0, std_list, G_NULL_OPTS },
+	{ "load", G_FLAG_VERBOSE | G_FLAG_LOADKLD, std_load, G_NULL_OPTS },
+	{ "unload", G_FLAG_VERBOSE, std_unload, G_NULL_OPTS },
+	G_CMD_SENTINEL
+};
+
+static void
+std_usage(const char *name)
+{
+	struct g_command *cmd;
+	struct g_option *opt;
+	unsigned i, j;
+
+	for (i = 0; ; i++) {
+		cmd = &class_commands[i];
+		if (cmd->gc_name == NULL)
+			break;
+		fprintf(stderr, "%s %s %s %s", i == 0 ? "usage:" : "      ",
+		    name, class_name, cmd->gc_name);
+		if ((cmd->gc_flags & G_FLAG_VERBOSE) != 0)
+			fprintf(stderr, " [-v]");
+		for (j = 0; ; j++) {
+			opt = &cmd->gc_options[j];
+			if (opt->go_name == NULL)
+				break;
+			if (opt->go_val != NULL || opt->go_type == G_TYPE_NONE)
+				fprintf(stderr, " [");
+			else
+				fprintf(stderr, " ");
+			fprintf(stderr, "-%c", opt->go_char);
+			if (opt->go_type != G_TYPE_NONE)
+				fprintf(stderr, " %s", opt->go_name);
+			if (opt->go_val != NULL || opt->go_type == G_TYPE_NONE)
+				fprintf(stderr, "]");
+		}
+		fprintf(stderr, " ...\n");
+	}
+	exit(EXIT_FAILURE);
+}
+
+static void
+geom_usage(void)
+{
+
+	if (class_name == NULL) {
+		errx(EXIT_FAILURE, "usage: %s <class name> <command> "
+		    "[options]", "geom");
+	} else {
+		const char *prefix;
+		unsigned i;
+
+		if (usage == NULL)
+			prefix = "usage:";
+		else {
+			usage(comm);
+			prefix = "      ";
+		}
+		for (i = 0; ; i++) {
+			struct g_command *cmd;
+
+			cmd = &std_commands[i];
+			if (cmd->gc_name == NULL)
+				break;
+			if (find_command(cmd->gc_name, 0) != NULL)
+				continue;
+			if (!std_available(cmd->gc_name))
+				continue;
+			fprintf(stderr, "%s %s %s", prefix, comm, cmd->gc_name);
+			if ((cmd->gc_flags & G_FLAG_VERBOSE) != 0)
+				fprintf(stderr, " [-v]");
+			fprintf(stderr, "\n");
+			prefix = "      ";
+		}
+		exit(EXIT_FAILURE);
+	}
+}
+
+static void
+load_module(void)
+{
+	char name1[64], name2[64];
+
+	snprintf(name1, sizeof(name1), "g_%s", class_name);
+	snprintf(name2, sizeof(name2), "geom_%s", class_name);
+	if (modfind(name1) < 0) {
+		/* Not present in kernel, try loading it. */
+		if (kldload(name2) < 0 || modfind(name1) < 0) {
+			if (errno != EEXIST) {
+				errx(EXIT_FAILURE,
+				    "%s module not available!", name2);
+			}
+		}
+	}
+}
+
+static int
+strlcatf(char *str, size_t size, const char *format, ...)
+{
+	size_t len;
+	va_list ap;
+	int ret;
+
+	len = strlen(str);
+	str += len;
+	size -= len;
+
+	va_start(ap, format);
+	ret = vsnprintf(str, size, format, ap);
+	va_end(ap);
+
+	return (ret);
+}
+
+/*
+ * Find given option in options available for given command.
+ */
+static struct g_option *
+find_option(struct g_command *cmd, char ch)
+{
+	struct g_option *opt;
+	unsigned i;
+
+	for (i = 0; ; i++) {
+		opt = &cmd->gc_options[i];
+		if (opt->go_name == NULL)
+			return (NULL);
+		if (opt->go_char == ch)
+			return (opt);
+	}
+	/* NOTREACHED */
+	return (NULL);
+}
+
+/*
+ * Add given option to gctl_req.
+ */
+static void
+set_option(struct gctl_req *req, struct g_option *opt, const char *val)
+{
+
+	if (opt->go_type == G_TYPE_NUMBER) {
+		intmax_t number;
+
+		errno = 0;
+		number = strtoimax(optarg, NULL, 0);
+		if (errno != 0) {
+			err(EXIT_FAILURE, "Invalid value for '%c' argument.",
+			    opt->go_char);
+		}
+		opt->go_val = malloc(sizeof(intmax_t));
+		if (opt->go_val == NULL)
+			errx(EXIT_FAILURE, "No memory.");
+		*(intmax_t *)opt->go_val = number;
+
+		gctl_ro_param(req, opt->go_name, sizeof(intmax_t), opt->go_val);
+	} else if (opt->go_type == G_TYPE_STRING) {
+		gctl_ro_param(req, opt->go_name, -1, optarg);
+	} else /* if (opt->go_type == G_TYPE_NONE) */ {
+		opt->go_val = malloc(sizeof(int));
+		if (opt->go_val == NULL)
+			errx(EXIT_FAILURE, "No memory.");
+		*(int *)opt->go_val = *val - '0';
+
+		gctl_ro_param(req, opt->go_name, sizeof(int),
+		    opt->go_val);
+	}
+}
+
+/*
+ * 1. Add given argument by caller.
+ * 2. Add default values of not given arguments.
+ * 3. Add the rest of arguments.
+ */
+static void
+parse_arguments(struct g_command *cmd, struct gctl_req *req, int *argc,
+    char ***argv)
+{
+	struct g_option *opt;
+	char opts[64];
+	unsigned i;
+	int ch;
+
+	*opts = '\0';
+	if ((cmd->gc_flags & G_FLAG_VERBOSE) != 0)
+		strlcat(opts, "v", sizeof(opts));
+	for (i = 0; ; i++) {
+		opt = &cmd->gc_options[i];
+		if (opt->go_name == NULL)
+			break;
+		strlcatf(opts, sizeof(opts), "%c", opt->go_char);
+		if (opt->go_type != G_TYPE_NONE)
+			strlcat(opts, ":", sizeof(opts));
+	}
+
+	/*
+	 * Add specified arguments.
+	 */
+	while ((ch = getopt(*argc, *argv, opts)) != -1) {
+		/* Standard (not passed to kernel) options. */
+		switch (ch) {
+		case 'v':
+			verbose = 1;
+			continue;
+		}
+		/* Options passed to kernel. */
+		opt = find_option(cmd, ch);
+		if (opt == NULL)
+			geom_usage();
+		if (G_OPT_ISDONE(opt)) {
+			fprintf(stderr, "Flag '%c' specified twice.\n",
+			    opt->go_char);
+			geom_usage();
+		}
+		G_OPT_DONE(opt);
+
+		if (opt->go_type == G_TYPE_NONE)
+			set_option(req, opt, "1");
+		else
+			set_option(req, opt, optarg);
+	}
+	*argc -= optind;
+	*argv += optind;
+
+	/*
+	 * Add not specified arguments, but with default values.
+	 */
+	for (i = 0; ; i++) {
+		opt = &cmd->gc_options[i];
+		if (opt->go_name == NULL)
+			break;
+		if (G_OPT_ISDONE(opt))
+			continue;
+
+		if (opt->go_type == G_TYPE_NONE) {
+			assert(opt->go_val == NULL);
+			set_option(req, opt, "0");
+		} else {
+			if (opt->go_val == NULL) {
+				fprintf(stderr, "Flag '%c' not specified.\n",
+				    opt->go_char);
+				geom_usage();
+			} else {
+				if (opt->go_type == G_TYPE_NUMBER) {
+					gctl_ro_param(req, opt->go_name,
+					    sizeof(intmax_t), opt->go_val);
+				} else /* if (opt->go_type == G_TYPE_STRING)*/ {
+					gctl_ro_param(req, opt->go_name, -1,
+					    opt->go_val);
+				}
+			}
+		}
+	}
+	/*
+	 * Add rest of given arguments.
+	 */
+	gctl_ro_param(req, "nargs", sizeof(int), argc);
+	for (i = 0; i < (unsigned)*argc; i++) {
+		char argname[16];
+
+		snprintf(argname, sizeof(argname), "arg%u", i);
+		gctl_ro_param(req, argname, -1, (*argv)[i]);
+	}
+}
+
+/*
+ * Find given command in commands available for given class.
+ */
+static struct g_command *
+find_command(const char *cmdstr, int all)
+{
+	struct g_command *cmd;
+	unsigned i;
+
+	/*
+	 * First try to find command defined by loaded library.
+	 */
+	if (class_commands != NULL) {
+		for (i = 0; ; i++) {
+			cmd = &class_commands[i];
+			if (cmd->gc_name == NULL)
+				break;
+			if (strcmp(cmd->gc_name, cmdstr) == 0)
+				return (cmd);
+		}
+	}
+	if (!all)
+		return (NULL);
+	/*
+	 * Now try to find in standard commands.
+	 */
+	for (i = 0; ; i++) {
+		cmd = &std_commands[i];
+		if (cmd->gc_name == NULL)
+			break;
+		if (!std_available(cmd->gc_name))
+			continue;
+		if (strcmp(cmd->gc_name, cmdstr) == 0)
+			return (cmd);
+	}
+	return (NULL);
+}
+
+static unsigned
+set_flags(struct g_command *cmd)
+{
+	unsigned flags = 0;
+
+	if ((cmd->gc_flags & G_FLAG_VERBOSE) != 0 && verbose)
+		flags |= G_FLAG_VERBOSE;
+
+	return (flags);
+}
+
+/*
+ * Run command.
+ */
+static void
+run_command(int argc, char *argv[])
+{
+	struct g_command *cmd;
+	struct gctl_req *req;
+	const char *errstr;
+	char buf[4096];
+
+	cmd = find_command(argv[0], 1);
+	if (cmd == NULL) {
+		fprintf(stderr, "Unknown command: %s\n", argv[0]);
+		geom_usage();
+	}
+	if ((cmd->gc_flags & G_FLAG_LOADKLD) != 0)
+		load_module();
+
+	req = gctl_get_handle();
+	gctl_ro_param(req, "class", -1, gclass_name);
+	gctl_ro_param(req, "verb", -1, argv[0]);
+	if (version != NULL)
+		gctl_ro_param(req, "version", sizeof(*version), version);
+	parse_arguments(cmd, req, &argc, &argv);
+
+	if (cmd->gc_func != NULL) {
+		unsigned flags;
+
+		flags = set_flags(cmd);
+		cmd->gc_func(req, flags);
+		errstr = req->error;
+	} else {
+		bzero(buf, sizeof(buf));
+		gctl_rw_param(req, "output", sizeof(buf), buf);
+		errstr = gctl_issue(req);
+	}
+	if (errstr != NULL) {  
+		fprintf(stderr, "%s\n", errstr);
+		gctl_free(req);
+		exit(EXIT_FAILURE);
+	}
+	if (*buf != '\0')
+		printf("%s", buf);
+	gctl_free(req);
+	if (verbose)
+		printf("Done.\n");
+	exit(EXIT_SUCCESS);
+}
+
+static void
+load_library(void)
+{
+	char path[MAXPATHLEN];
+	uint32_t *lib_version;
+	void *dlh;
+
+	snprintf(path, sizeof(path), "%s/geom_%s.so", CLASSDIR, class_name);
+	dlh = dlopen(path, RTLD_NOW);
+	if (dlh == NULL) {
+#if 0
+		fprintf(stderr, "Cannot open library %s, but continuing "
+		    "anyway.\n", path);
+#endif
+		/*
+		 * Even if library cannot be loaded, standard commands are
+		 * available, so don't panic!
+		 */
+		return;
+	}
+	lib_version = dlsym(dlh, "lib_version");
+	if (lib_version == NULL) {
+		fprintf(stderr, "Cannot find symbol %s: %s.\n", "lib_version",
+		    dlerror());
+		dlclose(dlh);
+		exit(EXIT_FAILURE);
+	}
+	if (*lib_version != G_LIB_VERSION) {
+		dlclose(dlh);
+		errx(EXIT_FAILURE, "%s and %s are not synchronized.", comm,
+		    path);
+	}
+	version = dlsym(dlh, "version");
+	if (version == NULL) {
+		fprintf(stderr, "Cannot find symbol %s: %s.\n", "version",
+		    dlerror());
+		dlclose(dlh);
+		exit(EXIT_FAILURE);
+	}
+	class_commands = dlsym(dlh, "class_commands");
+	if (class_commands == NULL) {
+		fprintf(stderr, "Cannot find symbol %s: %s.\n",
+		    "class_commands", dlerror());
+		dlclose(dlh);
+		exit(EXIT_FAILURE);
+	}
+	usage = dlsym(dlh, "usage");
+	if (usage == NULL)
+		usage = std_usage;
+}
+
+/*
+ * Class name should be all capital letters.
+ */
+static void
+set_class_name(void)
+{
+	char *s1, *s2;
+
+	gclass_name = malloc(strlen(class_name));
+	if (gclass_name == NULL)
+		errx(EXIT_FAILURE, "No memory");
+	s1 = gclass_name;
+	s2 = class_name;
+	for (; *s2 != '\0'; s2++)
+		*s1++ = toupper(*s2);
+	*s1 = '\0';
+}
+
+static void
+get_class(int *argc, char ***argv)
+{
+
+	snprintf(comm, sizeof(comm), "%s", basename((*argv)[0]));
+	if (strcmp(comm, "geom") == 0) {
+		if (*argc < 2)
+			geom_usage();
+		strlcatf(comm, sizeof(comm), " %s", (*argv)[1]);
+		class_name = (*argv)[1];
+		*argc -= 2;
+		*argv += 2;
+	} else if (*comm == 'g') {
+		class_name = comm + 1;
+		*argc -= 1;
+		*argv += 1;
+	} else {
+		errx(EXIT_FAILURE, "Invalid utility name.");
+	}
+	set_class_name();
+	load_library();
+	if (*argc < 1)
+		geom_usage();
+}
+
+int
+main(int argc, char *argv[])
+{
+
+	get_class(&argc, &argv);
+	run_command(argc, argv);
+	/* NOTREACHED */
+
+	exit(EXIT_FAILURE);
+}
+
+static struct gclass *
+find_class(struct gmesh *mesh, const char *name)
+{
+	struct gclass *classp;
+
+	LIST_FOREACH(classp, &mesh->lg_class, lg_class) {
+		if (strcmp(classp->lg_name, name) == 0)
+			return (classp);
+	}
+	return (NULL);
+}
+
+static struct gprovider *
+find_provider(struct gclass *classp, const char *name)
+{
+	struct ggeom *gp;
+	struct gprovider *pp;
+
+	LIST_FOREACH(gp, &classp->lg_geom, lg_geom) {
+		LIST_FOREACH(pp, &gp->lg_provider, lg_provider) {
+			if (strcmp(pp->lg_name, name) == 0)
+				return (pp);
+		}
+	}
+	return (NULL);
+}
+
+static char *
+genspaces(const char *text, size_t len)
+{
+	static char spaces[256];
+	size_t outlen;
+
+	if (strlen(text) >= len) {
+		spaces[0] = '\0';
+		return (spaces);
+	}
+	memset(spaces, ' ', sizeof(spaces));
+	outlen = len - strlen(text);
+	if (outlen >= sizeof(spaces)) {
+		spaces[sizeof(spaces) - 1] = '\0';
+		return (spaces);
+	}
+	spaces[outlen] = '\0';
+	return (spaces);
+}
+
+static void
+show_one(struct gprovider *pp)
+{
+	struct gconfig *conf;
+
+	printf("       NAME: %s\n", pp->lg_name);
+	printf("  geom name: %s\n", pp->lg_geom->lg_name);
+	printf("  mediasize: %jd\n", (intmax_t)pp->lg_mediasize);
+	printf(" sectorsize: %u\n", pp->lg_sectorsize);
+	printf("       mode: %s\n", pp->lg_mode);
+	LIST_FOREACH(conf, &pp->lg_config, lg_config) {
+		printf("%s%s: %s\n", genspaces(conf->lg_name, 11),
+		    conf->lg_name, conf->lg_val);
+	}
+	printf("\n");
+}
+
+static int
+std_list_available(void)
+{
+	struct gmesh mesh;
+	struct gclass *classp;
+	int error;
+
+	error = geom_gettree(&mesh);
+	if (error != 0)
+		exit(EXIT_FAILURE);
+	classp = find_class(&mesh, gclass_name);
+	geom_deletetree(&mesh);
+	if (classp != NULL)
+		return (1);
+	return (0);
+}
+
+static void
+std_list(struct gctl_req *req, unsigned flags __unused)
+{
+	struct gmesh mesh;
+	struct gclass *classp;
+	struct gprovider *pp;
+	int error, *nargs;
+
+	error = geom_gettree(&mesh);
+	if (error != 0)
+		exit(EXIT_FAILURE);
+	classp = find_class(&mesh, gclass_name);
+	if (classp == NULL) {
+		geom_deletetree(&mesh);
+		fprintf(stderr, "Class %s not found.\n", gclass_name);
+		return;
+	}
+	nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs));
+	if (nargs == NULL) {
+		gctl_error(req, "No '%s' argument.", "nargs");
+		geom_deletetree(&mesh);
+		return;
+	}
+	if (*nargs > 0) {
+		int i;
+
+		for (i = 0; i < *nargs; i++) {
+			const char *name;
+			char param[16];
+
+			snprintf(param, sizeof(param), "arg%d", i);
+			name = gctl_get_asciiparam(req, param);
+			assert(name != NULL);
+			pp = find_provider(classp, name);
+			if (pp != NULL)
+				show_one(pp);
+			else {
+				fprintf(stderr, "No such provider: %s.\n",
+				    name);
+			}
+		}
+	} else {
+		struct ggeom *gp;
+
+		LIST_FOREACH(gp, &classp->lg_geom, lg_geom) {
+			LIST_FOREACH(pp, &gp->lg_provider, lg_provider) {
+				show_one(pp);
+			}
+		}
+	}
+	geom_deletetree(&mesh);
+}
+
+static int
+std_load_available(void)
+{
+	char name[MAXPATHLEN], paths[MAXPATHLEN * 8], *p;
+	struct stat sb;
+	size_t len;
+
+	snprintf(name, sizeof(name), "g_%s", class_name);
+	/*
+	 * If already in kernel, "load" command is not available.
+	 */
+	if (modfind(name) >= 0)
+		return (0);
+	bzero(paths, sizeof(paths));
+	len = sizeof(paths);
+	if (sysctlbyname("kern.module_path", paths, &len, NULL, 0) < 0)
+		err(EXIT_FAILURE, "sysctl(kern.module_path)");
+	for (p = strtok(paths, ";"); p != NULL; p = strtok(NULL, ";")) {
+		snprintf(name, sizeof(name), "%s/geom_%s.ko", p, class_name);
+		/*
+		 * If geom_<name>.ko file exists, "load" command is available.
+		 */
+		if (stat(name, &sb) == 0)
+			return (1);
+	}
+	return (0);
+}
+
+static void
+std_load(struct gctl_req *req __unused, unsigned flags)
+{
+
+	/*
+	 * Do nothing special here, because of G_FLAG_LOADKLD flag,
+	 * module is already loaded.
+	 */
+	if ((flags & G_FLAG_VERBOSE) != 0)
+		printf("Module available.\n");
+}
+
+static int
+std_unload_available(void)
+{
+	char name[64];
+	int id;
+
+	snprintf(name, sizeof(name), "geom_%s", class_name);
+	id = kldfind(name);
+	if (id >= 0)
+		return (1);
+	return (0);
+}
+
+static void
+std_unload(struct gctl_req *req, unsigned flags __unused)
+{
+	char name[64];
+	int id;
+
+	snprintf(name, sizeof(name), "geom_%s", class_name);
+	id = kldfind(name);
+	if (id < 0) {
+		gctl_error(req, "Could not find module: %s.", strerror(errno));
+		return;
+	}
+	if (kldunload(id) < 0) {
+		gctl_error(req, "Could not unload module: %s.",
+		    strerror(errno));
+		return;
+	}
+}
+
+static int
+std_available(const char *name)
+{
+
+	if (strcmp(name, "list") == 0)
+		return (std_list_available());
+	else if (strcmp(name, "load") == 0)
+		return (std_load_available());
+	else if (strcmp(name, "unload") == 0)
+		return (std_unload_available());
+	else
+		assert(!"Unknown standard command.");
+	return (0);
+}
diff --git a/sbin/geom/core/geom.h b/sbin/geom/core/geom.h
new file mode 100644
index 0000000..06b97a0
--- /dev/null
+++ b/sbin/geom/core/geom.h
@@ -0,0 +1,62 @@
+/*-
+ * Copyright (c) 2004 Pawel Jakub Dawidek <pjd@FreeBSD.org>
+ * 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.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHORS 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 AUTHORS 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.
+ *
+ * $FreeBSD$
+ */
+
+#ifndef _GEOM_H_
+#define	_GEOM_H_
+#define	G_LIB_VERSION	0
+
+#define	G_FLAG_NONE	0x0000
+#define	G_FLAG_VERBOSE	0x0001
+#define	G_FLAG_LOADKLD	0x0002
+
+#define	G_TYPE_NONE	0
+#define	G_TYPE_STRING	1
+#define	G_TYPE_NUMBER	2
+
+#define	G_OPT_MAX	16
+#define	G_OPT_DONE(opt)		(opt)->go_char = '\0'
+#define	G_OPT_ISDONE(opt)	((opt)->go_char == '\0')
+
+#define G_OPT_SENTINEL	{ '\0', NULL, NULL, G_TYPE_NONE }
+#define G_NULL_OPTS	{ G_OPT_SENTINEL }
+#define	G_CMD_SENTINEL	{ NULL, 0, NULL, G_NULL_OPTS }
+
+struct g_option {
+	char		 go_char;
+	const char	*go_name;
+	void		*go_val;
+	unsigned	 go_type;
+};
+
+struct g_command {
+	const char	*gc_name;
+	unsigned	 gc_flags;
+	void		(*gc_func)(struct gctl_req *, unsigned);
+	struct g_option	gc_options[G_OPT_MAX];
+};
+#endif	/* !_GEOM_H_ */
diff --git a/sbin/geom/misc/subr.c b/sbin/geom/misc/subr.c
new file mode 100644
index 0000000..9d72e34
--- /dev/null
+++ b/sbin/geom/misc/subr.c
@@ -0,0 +1,247 @@
+/*-
+ * Copyright (c) 2004 Pawel Jakub Dawidek <pjd@FreeBSD.org>
+ * 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.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHORS 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 AUTHORS 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.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+#include <sys/disk.h>
+#include <sys/endian.h>
+#include <sys/uio.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <paths.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdarg.h>
+#include <string.h>
+#include <strings.h>
+#include <unistd.h>
+#include <assert.h>
+#include <libgeom.h>
+
+#include "misc/subr.h"
+
+
+struct std_metadata {
+	char		md_magic[16];
+	uint32_t	md_version;
+};
+
+static void
+std_metadata_decode(const u_char *data, struct std_metadata *md)
+{
+
+        bcopy(data, md->md_magic, sizeof(md->md_magic));
+        md->md_version = le32dec(data + 16);
+}
+
+static void
+pathgen(const char *name, char *path, size_t size)
+{
+
+	if (strncmp(name, _PATH_DEV, strlen(_PATH_DEV)) != 0)
+		snprintf(path, size, "%s%s", _PATH_DEV, name);
+	else
+		strlcpy(path, name, size);
+}
+
+int
+g_metadata_store(const char *name, u_char *md, size_t size)
+{
+	char path[MAXPATHLEN];
+	unsigned sectorsize;
+	off_t mediasize;
+	u_char *sector;
+	int error, fd;
+
+	pathgen(name, path, sizeof(path));
+	sector = NULL;
+	error = 0;
+
+	fd = open(path, O_WRONLY);
+	if (fd == -1)
+		return (errno);
+	if (ioctl(fd, DIOCGMEDIASIZE, &mediasize) < 0) {
+		error = errno;
+		goto out;
+	}
+	if (ioctl(fd, DIOCGSECTORSIZE, &sectorsize) < 0) {
+		error = errno;
+		goto out;
+	}
+	assert(sectorsize >= size);
+	sector = malloc(sectorsize);
+	if (sector == NULL) {
+		error = ENOMEM;
+		goto out;
+	}
+	bcopy(md, sector, size);
+	if (pwrite(fd, sector, sectorsize, mediasize - sectorsize) !=
+	    (ssize_t)sectorsize) {
+		error = errno;
+		goto out;
+	}
+out:
+	if (sector != NULL)
+		free(sector);
+	close(fd);
+	return (error);
+}
+
+int
+g_metadata_clear(const char *name, const char *magic)
+{
+	struct std_metadata md;
+	char path[MAXPATHLEN];
+	unsigned sectorsize;
+	off_t mediasize;
+	u_char *sector;
+	int error, fd;
+
+	pathgen(name, path, sizeof(path));
+	sector = NULL;
+	error = 0;
+
+	fd = open(path, O_RDWR);
+	if (fd == -1)
+		return (errno);
+	if (ioctl(fd, DIOCGMEDIASIZE, &mediasize) < 0) {
+		error = errno;
+		goto out;
+	}
+	if (ioctl(fd, DIOCGSECTORSIZE, &sectorsize) < 0) {
+		error = errno;
+		goto out;
+	}
+	sector = malloc(sectorsize);
+	if (sector == NULL) {
+		error = ENOMEM;
+		goto out;
+	}
+	if (magic != NULL) {
+		if (pread(fd, sector, sectorsize, mediasize - sectorsize) !=
+		    (ssize_t)sectorsize) {
+			error = errno;
+			goto out;
+		}
+		std_metadata_decode(sector, &md);
+		if (strcmp(md.md_magic, magic) != 0) {
+			error = EINVAL;
+			goto out;
+		}
+	}
+	bzero(sector, sectorsize);
+	if (pwrite(fd, sector, sectorsize, mediasize - sectorsize) !=
+	    (ssize_t)sectorsize) {
+		error = errno;
+		goto out;
+	}
+out:
+	if (sector != NULL)
+		free(sector);
+	close(fd);
+	return (error);
+}
+
+/*
+ * Set an error message, if one does not already exist.
+ */
+void
+gctl_error(struct gctl_req *req, const char *error, ...)
+{
+	va_list ap;
+
+	if (req->error != NULL)
+		return;
+	va_start(ap, error);
+	vasprintf(&req->error, error, ap);
+	va_end(ap);
+}
+
+void *
+gctl_get_param(struct gctl_req *req, const char *param, int *len)
+{
+	unsigned i;
+	void *p;
+	struct gctl_req_arg *ap;
+
+	for (i = 0; i < req->narg; i++) {
+		ap = &req->arg[i];
+		if (strcmp(param, ap->name))
+			continue;
+		if (!(ap->flag & GCTL_PARAM_RD))
+			continue;
+		p = ap->value;
+		if (len != NULL)
+			*len = ap->len;
+		return (p);
+	}
+	return (NULL);
+}
+
+char const *
+gctl_get_asciiparam(struct gctl_req *req, const char *param)
+{
+	unsigned i;
+	char const *p;
+	struct gctl_req_arg *ap;
+
+	for (i = 0; i < req->narg; i++) {
+		ap = &req->arg[i];
+		if (strcmp(param, ap->name))
+			continue;
+		if (!(ap->flag & GCTL_PARAM_RD))
+			continue;
+		p = ap->value;
+		if (ap->len < 1) {
+			gctl_error(req, "No length argument (%s)", param);
+			return (NULL);
+		}
+		if (p[ap->len - 1] != '\0') {
+			gctl_error(req, "Unterminated argument (%s)", param);
+			return (NULL);
+		}
+		return (p);
+	}
+	return (NULL);
+}
+
+void *
+gctl_get_paraml(struct gctl_req *req, const char *param, int len)
+{
+	int i;
+	void *p;
+
+	p = gctl_get_param(req, param, &i);
+	if (p == NULL)
+		gctl_error(req, "Missing %s argument", param);
+	else if (i != len) {
+		p = NULL;
+		gctl_error(req, "Wrong length %s argument", param);
+	}
+	return (p);
+}
diff --git a/sbin/geom/misc/subr.h b/sbin/geom/misc/subr.h
new file mode 100644
index 0000000..487f3db
--- /dev/null
+++ b/sbin/geom/misc/subr.h
@@ -0,0 +1,38 @@
+/*-
+ * Copyright (c) 2004 Pawel Jakub Dawidek <pjd@FreeBSD.org>
+ * 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.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHORS 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 AUTHORS 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.
+ *
+ * $FreeBSD$
+ */
+
+#ifndef _SUBR_H_
+#define	_SUBR_H_
+int g_metadata_store(const char *name, u_char *md, size_t size);
+int g_metadata_clear(const char *name, const char *magic);
+
+void gctl_error(struct gctl_req *req, const char *error, ...);
+void *gctl_get_param(struct gctl_req *req, const char *param, int *len);
+char const *gctl_get_asciiparam(struct gctl_req *req, const char *param);
+void *gctl_get_paraml(struct gctl_req *req, const char *param, int len);
+#endif	/* !_SUBR_H_ */