1 files changed, 189 insertions, 0 deletions
diff --git a/share/examples/lkm/misc/module/miscmod.c b/share/examples/lkm/misc/module/miscmod.c
new file mode 100644
index 0000000..04aa07c
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+++ b/share/examples/lkm/misc/module/miscmod.c
@@ -0,0 +1,189 @@
+/* 25 May 93*/
+/*
+ * Makefile for miscmod
+ *
+ * 05 Jun 93	Terry Lambert		Split mycall.c out
+ * 25 May 93	Terry Lambert		Original
+ *
+ * Copyright (c) 1993 Terrence R. Lambert.
+ * 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 Terrence R. Lambert.
+ * 4. The name Terrence R. Lambert may not be used to endorse or promote
+ *    products derived from this software without specific prior written
+ *    permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY TERRENCE R. LAMBERT ``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 TERRENCE R. LAMBERT 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/param.h>
+#include <sys/ioctl.h>
+#include <sys/systm.h>
+#include <sys/conf.h>
+#include <sys/mount.h>
+#include <sys/exec.h>
+#include <sys/lkm.h>
+#include <a.out.h>
+#include <sys/file.h>
+#include <sys/errno.h>
+
+
+extern int	misccall();
+
+/*
+ * These two entries define our system call and module information.  We
+ * have 0 arguments to our system call.
+ */
+static struct sysent newent = {
+	0,	misccall		/* # of args, function pointer*/
+};
+
+/*
+ * Miscellaneous modules must have their own save areas...
+ */
+static struct sysent	oldent;		/* save are for old callslot entry*/
+
+MOD_MISC( "miscmod")
+
+
+/*
+ * This function is called each time the module is loaded or unloaded.
+ * Since we are a miscellaneous module, we have to provide whatever
+ * code is necessary to patch ourselves into the area we are being
+ * loaded to change.
+ *
+ * For the system call table, we duplicate the code in the kern_lkm.c
+ * file for patching into the system call table.  We can tell what
+ * has been allocated, etc. by virtue of the fact that we know the
+ * criteria used by the system call loader interface.  We still
+ * kick out the copyright to the console here (to give an example).
+ *
+ * The stat information is basically common to all modules, so there
+ * is no real issue involved with stat; we will leave it nosys(),
+ * cince we don't have to do anything about it.
+ */
+static int
+miscmod_handle( lkmtp, cmd)
+struct lkm_table	*lkmtp;
+int			cmd;
+{
+	int			i;
+	struct lkm_misc		*args = lkmtp->private.lkm_misc;
+	int			err = 0;	/* default = success*/
+	extern int		nsysent;	/* init_sysent.c*/
+	extern int		lkmnosys();	/* allocable slot*/
+
+	switch( cmd) {
+	case LKM_E_LOAD:
+
+		/*
+		 * Don't load twice! (lkmexists() is exported by kern_lkm.c)
+		 */
+		if( lkmexists( lkmtp))
+			return( EEXIST);
+
+		/*
+		 * This is where we would express a slot preference if
+		 * we had one; since we don't, we will simply duplicate
+		 * the "auto" code and forget the other.
+		 */
+
+		/*
+		 * Search the table looking for a slot...
+		 */
+		for( i = 0; i < nsysent; i++)
+			if( sysent[ i].sy_call == lkmnosys)
+				break;		/* found it!*/
+		/* out of allocable slots?*/
+		if( i == nsysent) {
+			err = ENFILE;
+			break;
+		}
+
+		/* save old -- we must provide our own data area*/
+		bcopy( &sysent[ i], &oldent, sizeof( struct sysent));
+
+		/* replace with new*/
+		bcopy( &newent, &sysent[ i], sizeof( struct sysent));
+
+		/* done!*/
+		args->lkm_offset = i;	/* slot in sysent[]*/
+
+
+		/* if we make it to here, print copyright on console*/
+		printf( "\nSample Loaded miscellaneous module (system call)\n");
+		printf( "Copyright (c) 1993\n");
+		printf( "Terrence R. Lambert\n");
+		printf( "All rights reserved\n");
+
+		break;		/* Success*/
+
+	case LKM_E_UNLOAD:
+		/* current slot...*/
+		i = args->lkm_offset;
+
+		/* replace current slot contents with old contents*/
+		bcopy( &oldent, &sysent[ i], sizeof( struct sysent));
+
+		break;		/* Success*/
+
+	default:	/* we only understand load/unload*/
+		err = EINVAL;
+		break;
+	}
+
+	return( err);
+}
+
+
+/*
+ * External entry point; should generally match name of .o file.  The
+ * arguments are always the same for all loaded modules.  The "load",
+ * "unload", and "stat" functions in "DISPATCH" will be called under
+ * their respective circumstances unless their value is "nosys".  If
+ * called, they are called with the same arguments (cmd is included to
+ * allow the use of a single function, ver is included for version
+ * matching between modules and the kernel loader for the modules).
+ *
+ * Since we expect to link in the kernel and add external symbols to
+ * the kernel symbol name space in a future version, generally all
+ * functions used in the implementation of a particular module should
+ * be static unless they are expected to be seen in other modules or
+ * to resolve unresolved symbols alread existing in the kernel (the
+ * second case is not likely to ever occur).
+ *
+ * The entry point should return 0 unless it is refusing load (in which
+ * case it should return an errno from errno.h).
+ */
+miscmod( lkmtp, cmd, ver)
+struct lkm_table	*lkmtp;	
+int			cmd;
+int			ver;
+{
+	DISPATCH(lkmtp,cmd,ver,miscmod_handle,miscmod_handle,nosys)
+}
+
+
+/*
+ * EOF -- This file has not been truncated.
+ */