xref: /netbsd-src/sbin/mount_puffs/mount_puffs.c (revision 7d62b00eb9ad855ffcd7da46b41e23feb5476fac)
1 /*	$NetBSD: mount_puffs.c,v 1.5 2016/11/23 14:33:29 pho Exp $	*/
2 
3 /*
4  * Copyright (c) 2010 Antti Kantee.  All Rights Reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
16  * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
17  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
18  * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
21  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 /*
29  * This is to support -o getargs without having to replicate it in
30  * every file server. It also allows puffs filesystems to be mounted
31  * via "mount -a".
32  */
33 
34 #include <sys/cdefs.h>
35 #ifndef lint
36 __RCSID("$NetBSD: mount_puffs.c,v 1.5 2016/11/23 14:33:29 pho Exp $");
37 #endif /* !lint */
38 
39 #include <sys/param.h>
40 #include <sys/mount.h>
41 
42 #include <fs/puffs/puffs_msgif.h>
43 
44 #include <err.h>
45 #include <stdio.h>
46 #include <stdlib.h>
47 #include <string.h>
48 #include <sys/cdefs.h>
49 #include <unistd.h>
50 #include <util.h>
51 
52 static int
53 usage(void)
54 {
55 
56 	fprintf(stderr, "usage: %s [-o options] program[#source] mountpoint\n", getprogname());
57 	return 1;
58 }
59 
60 static int show_puffs_mount_args(const char *mountpoint)
61 {
62 	const char *vtypes[] = { VNODE_TYPES };
63 	struct puffs_kargs kargs;
64 
65 	if (mount(MOUNT_PUFFS, mountpoint, MNT_GETARGS, &kargs, sizeof(kargs)) == -1)
66 		err(1, "mount");
67 
68 	printf("version=%d, ", kargs.pa_vers);
69 	printf("flags=0x%x, ", kargs.pa_flags);
70 
71 	printf("root cookie=%p, ", kargs.pa_root_cookie);
72 	printf("root type=%s", vtypes[kargs.pa_root_vtype]);
73 
74 	if (kargs.pa_root_vtype != VDIR)
75 		printf(", root size=%llu",
76 		    (unsigned long long)kargs.pa_root_vsize);
77 	if (kargs.pa_root_vtype == VCHR || kargs.pa_root_vtype == VBLK)
78 		printf(", root rdev=0x%" PRIx64, (uint64_t)kargs.pa_root_rdev);
79 	printf("\n");
80 
81 	return 0;
82 }
83 
84 static int
85 mount_puffs_filesystem(const char *program, const char *opts,
86 					const char *source, const char *mountpoint)
87 {
88 	int argc = 0;
89 	const char **argv;
90 	int rv = 0;
91 
92 	/* Construct an argument vector:
93 	 * program [-o opts] [source] mountpoint */
94 	argv = ecalloc(1 + 2 + 1 + 1, sizeof(*argv));
95 	argv[argc++] = program;
96 	if (opts != NULL) {
97 		argv[argc++] = "-o";
98 		argv[argc++] = opts;
99 	}
100 	if (source != NULL) {
101 		argv[argc++] = source;
102 	}
103 	argv[argc++] = mountpoint;
104 	argv[argc] = NULL;
105 
106 	/* We intentionally use execvp(3) here because the program can
107 	 * actually be a basename. */
108 	if (execvp(program, __UNCONST(argv)) == -1) {
109 		warn("Cannot execute %s", program);
110 		rv = 1;
111 	}
112 
113 	free(argv);
114 	return rv;
115 }
116 
117 static void add_opt(char **opts, const char *opt)
118 {
119 	const size_t orig_len = *opts == NULL ? 0 : strlen(*opts);
120 
121 	*opts = erealloc(*opts, orig_len + 1 + strlen(opt) + 1);
122 
123 	if (orig_len == 0) {
124 		strcpy(*opts, opt);
125 	}
126 	else {
127 		strcat(*opts, ",");
128 		strcat(*opts, opt);
129 	}
130 }
131 
132 int
133 main(int argc, char *argv[])
134 {
135 	int mntflags = 0;
136 	int ch;
137 	char *opts = NULL;
138 	int rv = 0;
139 
140 	while ((ch = getopt(argc, argv, "o:")) != -1) {
141 		switch (ch) {
142 		case 'o':
143 			for (char *opt = optarg; (opt = strtok(opt, ",")) != NULL; opt = NULL) {
144 				if (strcmp(opt, "getargs") == 0) {
145 					mntflags |= MNT_GETARGS;
146 					break; /* No need to parse it any further. */
147 				}
148 				else {
149 					add_opt(&opts, opt);
150 				}
151 			}
152 			break;
153 		default:
154 			rv = usage();
155 			goto free_opts;
156 		}
157 	}
158 	argc -= optind;
159 	argv += optind;
160 
161 	if (argc != 2) {
162 		rv = usage();
163 		goto free_opts;
164 	}
165 
166 	if (mntflags & MNT_GETARGS) {
167 		/* Special case for -o getargs: retrieve kernel arguments for
168 		 * an already mounted filesystem. */
169 		rv = show_puffs_mount_args(argv[1]);
170 	}
171 	else {
172 		/* Split the program name and source. This is to allow
173 		 * filesystems to be mounted via "mount -a" i.e. /etc/fstab */
174 		char *source  = argv[0];
175 		char *program = strsep(&source, "#");
176 
177 		rv = mount_puffs_filesystem(program, opts, source, argv[1]);
178 	}
179 
180 free_opts:
181 	free(opts);
182 	return rv;
183 }
184