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      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