Added getbootfile(3), for an easy C interface to the kern.bootfile MIB

variable.  This one's even documented!

3 files changed, 140 insertions, 13 deletions

diff --git a/lib/libc/gen/Makefile.inc b/lib/libc/gen/Makefile.inc
index fb34e8b..cdf42dd 100644
--- a/lib/libc/gen/Makefile.inc
+++ b/lib/libc/gen/Makefile.inc
@@ -1,24 +1,25 @@
 #	From: @(#)Makefile.inc	8.3 (Berkeley) 4/16/94
-#	$Id$
+#	$Id: Makefile.inc,v 1.10 1994/09/23 00:37:43 wollman Exp $
 
 # machine-independent gen sources
 .PATH: ${.CURDIR}/${MACHINE}/gen ${.CURDIR}/gen
 
 SRCS+=	alarm.c assert.c clock.c closedir.c confstr.c crypt.c ctermid.c \
 	daemon.c devname.c disklabel.c err.c errlst.c \
-	exec.c fnmatch.c frexp.c fstab.c fts.c getbsize.c getcap.c getcwd.c \
-	getdomainname.c getgrent.c getgrouplist.c gethostname.c getloadavg.c \
-	getlogin.c getmntinfo.c getnetgrent.c getosreldate.c getpagesize.c \
-	getpass.c getpwent.c getttyent.c getusershell.c glob.c initgroups.c \
-	isatty.c msgctl.c msgget.c msgrcv.c msgsnd.c nice.c nlist.c \
-	ntp_gettime.c opendir.c pause.c popen.c psignal.c pwcache.c raise.c \
-	readdir.c rewinddir.c scandir.c seekdir.c semconfig.c semctl.c \
-	semget.c semop.c setdomainname.c sethostname.c setjmperr.c setmode.c \
-	shmat.c shmctl.c shmdt.c shmget.c siginterrupt.c siglist.c signal.c \
+	exec.c fnmatch.c frexp.c fstab.c fts.c getbootfile.c getbsize.c \
+	getcap.c getcwd.c getdomainname.c getgrent.c getgrouplist.c \
+	gethostname.c getloadavg.c getlogin.c getmntinfo.c getnetgrent.c \
+	getosreldate.c getpagesize.c getpass.c getpwent.c getttyent.c \
+	getusershell.c getvfsent.c glob.c initgroups.c isatty.c msgctl.c \
+	msgget.c msgrcv.c msgsnd.c nice.c nlist.c ntp_gettime.c opendir.c \
+	pause.c popen.c psignal.c pwcache.c raise.c readdir.c rewinddir.c \
+	scandir.c seekdir.c semconfig.c semctl.c semget.c semop.c \
+	setdomainname.c sethostname.c setjmperr.c setmode.c shmat.c \
+	shmctl.c shmdt.c shmget.c siginterrupt.c siglist.c signal.c \
 	sigsetjmp.c sigsetops.c sleep.c sysconf.c sysctl.c syslog.c \
 	telldir.c termios.c time.c times.c timezone.c ttyname.c ttyslot.c \
 	ualarm.c uname.c unvis.c usleep.c utime.c valloc.c vis.c wait.c \
-	wait3.c waitpid.c getvfsent.c
+	wait3.c waitpid.c
 
 # *rand48 family, from 1.1.5
 SRCS+=	_rand48.c drand48.c erand48.c jrand48.c lcong48.c lrand48.c \
@@ -36,8 +37,8 @@ errlst.o errlst.po:
 .endif
 
 MAN3+=	gen/alarm.3 gen/clock.3 gen/confstr.3 gen/crypt.3 gen/ctermid.3 \
-	gen/daemon.3 gen/devname.3 gen/directory.3 gen/err.3 \
-	gen/exec.3 gen/fnmatch.3 gen/frexp.3 gen/fts.3 gen/getbsize.3 \
+	gen/daemon.3 gen/devname.3 gen/directory.3 gen/err.3 gen/exec.3 \
+	gen/fnmatch.3 gen/frexp.3 gen/fts.3 gen/getbsize.3 gen/getbootfile.3 \
 	gen/getcap.3 gen/getcwd.3 gen/getdiskbyname.3 gen/getfsent.3 \
 	gen/getgrent.3 gen/getgrouplist.3 gen/gethostname.3 gen/getloadavg.3 \
 	gen/getmntinfo.3 gen/getnetgrent.3 gen/getpagesize.3 gen/getpass.3 \
diff --git a/lib/libc/gen/getbootfile.3 b/lib/libc/gen/getbootfile.3
new file mode 100644
index 0000000..cfab748
--- /dev/null
+++ b/lib/libc/gen/getbootfile.3
@@ -0,0 +1,71 @@
+.\" Copyright (c) 1983, 1991, 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.
+.\"
+.\"     From: @(#)gethostname.3	8.1 (Berkeley) 6/4/93
+.\"	$Id$
+.\"
+.Dd September 23, 1994
+.Dt GETBOOTFILE 3
+.Os
+.Sh NAME
+.Nm getbootfile
+.Nd get kernel boot file name
+.Sh SYNOPSIS
+.Fd #include <paths.h>
+.Ft const char *
+.Fn getbootfile void
+.Sh DESCRIPTION
+The
+.Nm getbootfile
+function retrieves the full pathname of the file from which the
+current kernel was loaded, and returns a static pointer to the name.
+A read/write interface to this information is available via the
+.Xr sysctl 2
+MIB variable
+.Dq Li kern.bootfile .
+.Sh RETURN VALUES
+If the call succeeds a string giving the pathname is returned.  If it
+fails, a a null pointer is returned and an error code is
+placed in the global location
+.Va errno .
+.Sh SEE ALSO
+.Xr sysctl 2
+.Sh BUGS
+If the boot blocks have not been modified to pass this information into
+the kernel at boot time, the static string
+.Dq Pa /kernel
+is returned instead of the real boot file.
+.Sh HISTORY
+The
+.Nm
+function call appeared in
+.Tn FreeBSD
+2.0.
diff --git a/lib/libc/gen/getbootfile.c b/lib/libc/gen/getbootfile.c
new file mode 100644
index 0000000..909b5f1
--- /dev/null
+++ b/lib/libc/gen/getbootfile.c
@@ -0,0 +1,55 @@
+/*
+ * 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[] = "From: @(#)gethostname.c	8.1 (Berkeley) 6/4/93";*/
+static const char rcsid[] =
+	"$Id$";
+#endif /* LIBC_SCCS and not lint */
+
+#include <sys/param.h>
+#include <sys/sysctl.h>
+
+const char *
+getbootfile(void)
+{
+	static char name[MAXPATHLEN];
+	size_t size = sizeof name;
+	int mib[2];
+
+	mib[0] = CTL_KERN;
+	mib[1] = KERN_BOOTFILE;
+	if (sysctl(mib, 2, name, &size, NULL, 0) == -1)
+		return (0);
+	return (name);
+}