Initial kenv(1) hack for dumping the kernel environment. This can be

used to extract modified boot hints to make loader(8)-time changes
"sticky".  It tries to use \ style quoting so that it can be used directly
with foo.conf files.  It can also extract specific variables.

3 files changed, 186 insertions, 0 deletions

diff --git a/bin/kenv/Makefile b/bin/kenv/Makefile
new file mode 100644
index 0000000..33a6dfc
--- /dev/null
+++ b/bin/kenv/Makefile
@@ -0,0 +1,5 @@
+# $FreeBSD$
+
+PROG=	kenv
+
+.include <bsd.prog.mk>
diff --git a/bin/kenv/kenv.1 b/bin/kenv/kenv.1
new file mode 100644
index 0000000..e80b944
--- /dev/null
+++ b/bin/kenv/kenv.1
@@ -0,0 +1,50 @@
+.\" Copyright (c) 2000  Peter Wemm <peter@freebsd.org>
+.\"
+.\" 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.
+.\"
+.\" $FreeBSD$
+.\"
+.Dd June 6, 1993
+.Dt KENV 1
+.Os BSD 4
+.Sh NAME
+.Nm kenv
+.Nd dump the kernel environment
+.Sh SYNOPSIS
+.Nm kenv
+.Op Fl h
+.Op variable
+.Sh DESCRIPTION
+.Nm kenv
+will dump the kernel environment.
+If the
+.Fl h
+flag is specified, it will limit the report to kernel probe hints.
+If an optional variable name is specified,
+.Nm
+will only report that value.
+.Sh SEE ALSO
+.Xr loader 8
+.Sh HISTORY
+.Nm kenv
+appeared in
+.Fx 5.0 .
diff --git a/bin/kenv/kenv.c b/bin/kenv/kenv.c
new file mode 100644
index 0000000..4e5970a
--- /dev/null
+++ b/bin/kenv/kenv.c
@@ -0,0 +1,131 @@
+/*
+ * Copyright (c) 2000  Peter Wemm <peter@freebsd.org>
+ *
+ * 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.
+ *
+ * $FreeBSD$
+ */
+#include <sys/types.h>
+#include <sys/sysctl.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <errno.h>
+#include <err.h>
+#include <unistd.h>
+
+static char sbuf[1024];
+
+static void
+usage(void)
+{
+	errx(1, "usage: [-h] [variable]");
+}
+
+int
+main(int argc, char **argv)
+{
+	int name2oid_oid[2];
+	int real_oid[CTL_MAXNAME+4];
+	size_t oidlen;
+	int ch, error, hflag, i, slen;
+	char *env, *eq, *name, *var, *val;
+
+	hflag = 0;
+	env = NULL;
+	while ((ch = getopt(argc, argv, "h")) != -1) {
+		switch (ch) {
+		case 'h':
+			hflag++;
+			break;
+		default:
+			usage();
+		}
+	}
+	argc -= optind;
+	argv += optind;
+	if (argc > 0) {
+		env = argv[0];
+		argv++;
+		argc--;
+	}
+	if (argc > 0)
+		usage();
+	name2oid_oid[0] = 0;	/* This is magic & undocumented! */
+	name2oid_oid[1] = 3;
+	oidlen = sizeof(real_oid);
+	name = "kern.environment";
+	error = sysctl(name2oid_oid, 2, real_oid, &oidlen, name, strlen(name));
+	if (error < 0) 
+		err(1, "cannot find kern.environment base sysctl OID");
+	oidlen /= sizeof (int);
+	if (oidlen >= CTL_MAXNAME)
+		errx(1, "kern.environment OID is too large!");
+	real_oid[oidlen] = 0;
+	for (i = 0; ; i++) {
+		real_oid[oidlen + 1] = i;
+		slen = sizeof(sbuf) - 1;
+		error = sysctl(real_oid, oidlen + 2, sbuf, &slen, NULL, 0);
+		if (error < 0) {
+			if (errno != ENOENT)
+				err(1, "sysctl kern.environment.%d\n", i);
+			break;
+		}
+		sbuf[sizeof(sbuf) - 1] = '\0';
+		eq = strchr(sbuf, '=');
+		if (eq == NULL)
+			err(1, "malformed environment string: %s\n", sbuf);
+		var = sbuf;
+		*eq = '\0';
+		val = eq + 1;
+		if (env) {
+			if (strcmp(var, env) != 0)
+				continue;
+			printf("%s\n", val);
+			break;
+		}
+		if (hflag) {
+			if (strncmp(var, "hint.", 5) != 0)
+				continue;
+			/* FALLTHROUGH */
+		}
+		printf("%s=\"", var);
+		while (*val) {
+			switch (*val) {
+			case '"':
+				putchar('\\');
+				putchar('"');
+				break;
+			case '\\':
+				putchar('\\');
+				putchar('\\');
+				break;
+			default:
+				putchar(*val);
+				break;
+			}
+			val++;
+		}
+		printf("\"\n");
+	}
+	exit(0);
+}