example null file system built on top of the null layer in libpuffs

share/examples/puffs/pnullfs/Makefile

@@ -0,0 +1,11 @@
+#	$NetBSD: Makefile,v 1.1 2007/01/11 01:03:03 pooka Exp $
+
+PROG=	pnullfs
+LDADD+= -lpuffs -lutil
+DBG=-g -O0
+
+WARNS=	2
+
+NOMAN=	1
+
+.include <bsd.prog.mk>

share/examples/puffs/pnullfs/pnullfs.c

@@ -0,0 +1,130 @@
+/*	$NetBSD: pnullfs.c,v 1.1 2007/01/11 01:03:03 pooka Exp $	*/
+
+/*
+ * Copyright (c) 2007  Antti Kantee.  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. The name of the company nor the name of the author may be used to
+ *    endorse or promote products derived from this software without specific
+ *    prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
+ */
+
+/*
+ * pnullfs: puffs nullfs example
+ */
+
+#include <err.h>
+#include <puffs.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+PUFFSOP_PROTOS(puffs_null) /* XXX */
+
+static void usage(void);
+
+static void
+usage()
+{
+
+	errx(1, "usage: %s [-o mntopts] nullpath mountpath", getprogname());
+}
+
+int
+main(int argc, char *argv[])
+{
+	struct puffs_usermount *pu;
+	struct puffs_ops *pops;
+	struct statvfs svfsb;
+	struct stat sb;
+	mntoptparse_t mp;
+	int mntflags, pflags;
+	int ch;
+
+	setprogname(argv[0]);
+
+	if (argc < 3)
+		usage();
+
+	mntflags = 0;
+	while ((ch = getopt(argc, argv, "o:")) != -1) {
+		switch (ch) {
+		case 'o':
+			mp = getmntopts(optarg, puffsmopts, &mntflags, &pflags);
+			if (mp == NULL)
+				err(1, "getmntopts");
+			freemntopts(mp);
+			break;
+		}
+	}
+	pflags |= PUFFS_FLAG_BUILDPATH;
+	argv += optind;
+	argc -= optind;
+
+	if (argc != 2)
+		usage();
+
+	PUFFSOP_INIT(pops);
+
+	PUFFSOP_SET(pops, puffs_null, fs, statvfs);
+	PUFFSOP_SETFSNOP(pops, unmount);
+	PUFFSOP_SETFSNOP(pops, sync);
+
+	PUFFSOP_SET(pops, puffs_null, node, lookup);
+	PUFFSOP_SET(pops, puffs_null, node, create);
+	PUFFSOP_SET(pops, puffs_null, node, mknod);
+	PUFFSOP_SET(pops, puffs_null, node, getattr);
+	PUFFSOP_SET(pops, puffs_null, node, setattr);
+	PUFFSOP_SET(pops, puffs_null, node, remove);
+	PUFFSOP_SET(pops, puffs_null, node, link);
+	PUFFSOP_SET(pops, puffs_null, node, rename);
+	PUFFSOP_SET(pops, puffs_null, node, mkdir);
+	PUFFSOP_SET(pops, puffs_null, node, rmdir);
+	PUFFSOP_SET(pops, puffs_null, node, symlink);
+	PUFFSOP_SET(pops, puffs_null, node, readlink);
+	PUFFSOP_SET(pops, puffs_null, node, readdir);
+	PUFFSOP_SET(pops, puffs_null, node, read);
+	PUFFSOP_SET(pops, puffs_null, node, write);
+
+	if ((pu = puffs_mount(pops, argv[1], mntflags, "pnullfs", NULL,
+	    pflags, 0)) == NULL)
+		err(1, "mount");
+
+	if (statvfs(argv[0], &svfsb) == -1)
+		err(1, "statvfs %s", argv[0]);
+
+	pu->pu_pn_root = puffs_pn_new(pu, NULL);
+	if (pu->pu_pn_root == NULL)
+		err(1, "puffs_pn_new");
+	puffs_setrootpath(pu, argv[0]);
+	if (stat(argv[0], &sb) == -1)
+		err(1, "stat %s", argv[0]);
+	puffs_stat2vattr(&pu->pu_pn_root->pn_va, &sb);
+
+	if (puffs_start(pu, pu->pu_pn_root, &svfsb) == -1)
+		err(1, "puffs_start");
+
+	if (puffs_mainloop(pu, PUFFSLOOP_NODAEMON) == -1)
+		err(1, "mainloop");
+
+	return 0;
+}