xref: /titanic_52/usr/src/cmd/dfs.cmds/general/general.c (revision 68c47f65208790c466e5e484f2293d3baed71c6a)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
22 /*	  All Rights Reserved  	*/
23 
24 
25 /*
26  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
27  * Use is subject to license terms.
28  */
29 
30 /*
31  *	generic interface to dfs commands.
32  *
33  *	usage:	cmd [-F fstype] [-o fs_options] [ args ]
34  *
35  *	exec's /usr/lib/fs/<fstype>/<cmd>
36  *	<cmd> is the basename of the command.
37  *
38  *	if -F is missing, fstype is the first entry in /etc/dfs/fstypes
39  */
40 
41 #include <sys/types.h>
42 #include <sys/stat.h>
43 #include <ctype.h>
44 #include <stdio.h>
45 #include <stdlib.h>
46 #include <unistd.h>
47 #include <dirent.h>
48 #include <string.h>
49 
50 #define	DFSTYPES	"/etc/dfs/fstypes"		/* dfs list */
51 #define	FSCMD		"/usr/lib/fs/%s/%s"
52 
53 #define	ARGVPAD		4	/* non-[arg...] elements in new argv list: */
54 				/* cmd name, -o, opts, (char *)0 terminator */
55 
56 static char *getfs();
57 static int invalid();
58 void perror();
59 
60 int
61 main(argc, argv)
62 int argc;
63 char **argv;
64 {
65 	extern char *optarg;
66 	extern int optind;
67 	FILE *dfp;		/* fp for dfs list */
68 	int c, err = 0;
69 	char subcmd[BUFSIZ];	/* fs specific command */
70 	char *cmd;		/* basename of this command */
71 	char *fsname = NULL;	/* file system name */
72 	char *opts = NULL;	/* -o options */
73 	char **nargv;		/* new argv list */
74 	int nargc = 0;		/* new argc */
75 	static char usage[] =
76 		"usage: %s [-F fstype] [-o fs_options ] [arg ...]\n";
77 
78 	cmd = strrchr(argv[0], '/');	/* find the basename */
79 	if (cmd)
80 		++cmd;
81 	else
82 		cmd = argv[0];
83 
84 	while ((c = getopt(argc, argv, "F:o:")) != -1)
85 		switch (c) {
86 		case 'F':
87 			err |= (fsname != NULL);	/* at most one -F */
88 			fsname = optarg;
89 			break;
90 		case 'o':			/* fs specific options */
91 			err |= (opts != NULL);		/* at most one -o */
92 			opts = optarg;
93 			break;
94 		case '?':
95 			err = 1;
96 			break;
97 		}
98 	if (err) {
99 		(void) fprintf(stderr, usage, cmd);
100 		exit(1);
101 	}
102 
103 	if ((dfp = fopen(DFSTYPES, "r")) == NULL) {
104 		(void) fprintf(stderr, "%s: cannot open %s\n",
105 			cmd, DFSTYPES);
106 		exit(1);
107 	}
108 
109 	if (fsname) {		/* generate fs specific command name */
110 		if (invalid(fsname, dfp)) {	/* valid ? */
111 			(void) fprintf(stderr,
112 			    "%s: invalid file system name\n", cmd);
113 			(void) fprintf(stderr, usage, cmd);
114 			exit(1);
115 		} else {
116 			(void) snprintf(subcmd, sizeof (subcmd),
117 			    FSCMD, fsname, cmd);
118 		}
119 	} else if (fsname = getfs(dfp)) {	/* use 1st line in dfstypes */
120 		(void) snprintf(subcmd, sizeof (subcmd), FSCMD, fsname, cmd);
121 	} else {
122 		(void) fprintf(stderr,
123 		    "%s: no file systems in %s\n", cmd, DFSTYPES);
124 		(void) fprintf(stderr, usage, cmd);
125 		exit(1);
126 	}
127 
128 	/* allocate a block for the new argv list */
129 	if (!(nargv = (char **)malloc(sizeof (char *)*(argc-optind+ARGVPAD)))) {
130 		(void) fprintf(stderr, "%s: malloc failed.\n", cmd);
131 		exit(1);
132 		/*NOTREACHED*/
133 	}
134 	nargv[nargc++] = cmd;
135 	if (opts) {
136 		nargv[nargc++] = "-o";
137 		nargv[nargc++] = opts;
138 	}
139 	for (; optind <= argc; ++optind)	/* this copies the last NULL */
140 		nargv[nargc++] = argv[optind];
141 
142 	(void) execvp(subcmd, nargv);
143 	perror(subcmd);
144 	return (1);
145 }
146 
147 
148 /*
149  *	invalid(name, f)  -  return non-zero if name is not in
150  *			     the list of fs names in file f
151  */
152 
153 static int
154 invalid(name, f)
155 char *name;		/* file system name */
156 FILE *f;		/* file of list of systems */
157 {
158 	char *s;
159 
160 	while (s = getfs(f))	/* while there's still hope ... */
161 		if (strcmp(s, name) == 0)
162 			return (0);	/* we got it! */
163 	return (1);
164 }
165 
166 
167 /*
168  *	getfs(fp) - get the next file system name from fp
169  *		ignoring lines starting with a #.
170  *		All leading whitespace is discarded.
171  */
172 
173 static char buf[BUFSIZ];
174 
175 static char *
176 getfs(fp)
177 FILE *fp;
178 {
179 	char *s;
180 
181 	while (s = fgets(buf, BUFSIZ, fp)) {
182 		while (isspace(*s))	/* leading whitespace doesn't count */
183 			++s;
184 		if (*s != '#') {	/* not a comment */
185 			char *t = s;
186 
187 			while (!isspace(*t))	/* get the token */
188 				++t;
189 			*t = '\0';		/* ignore rest of line */
190 			return (s);
191 		}
192 	}
193 	return (NULL);	/* that's all, folks! */
194 }
195