xref: /illumos-gate/usr/src/cmd/dfs.cmds/dfshares/dfshares.c (revision 598f4ceed9327d2d6c2325dd67cae3aa06f7fea6)
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, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
23 /*	  All Rights Reserved  	*/
24 
25 
26 /*
27  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
28  * Use is subject to license terms.
29  */
30 
31 #pragma ident	"%Z%%M%	%I%	%E% SMI"
32 
33 /*
34  *	generic interface to dfshares, dfmounts.
35  *
36  *	usage:	dfshares [-F fstype] [-o fs_options] [-h] [ args ]
37  *
38  *	exec's /usr/lib/fs/<fstype>/<cmd>
39  *	<cmd> is the basename of the command.
40  *
41  *	if -F is missing, fstype is the first entry in /etc/dfs/fstypes
42  */
43 
44 #include <sys/types.h>
45 #include <sys/stat.h>
46 #include <ctype.h>
47 #include <stdio.h>
48 #include <dirent.h>
49 #include <string.h>
50 #include <errno.h>
51 #include <unistd.h>
52 #include <wait.h>
53 #include <stdlib.h>
54 
55 #define	DFSTYPES	"/etc/dfs/fstypes"		/* dfs list */
56 #define	FSCMD		"/usr/lib/fs/%s/%s"
57 
58 /*
59  * non-[arg...] elements in new argv list:
60  * cmd name, , -h, -o, opts, (char *)0 terminator
61  */
62 #define	ARGVPAD		5
63 
64 static char *getfs(FILE *);
65 static int invalid(const char *, FILE *);
66 
67 int
68 main(int argc, char **argv)
69 {
70 	FILE *dfp;		/* fp for dfs list */
71 	int c, err = 0;
72 	char subcmd[BUFSIZ];	/* fs specific command */
73 	char *cmd;		/* basename of this command */
74 	char *fsname = NULL;	/* file system name */
75 	char *opts = NULL;	/* -o options */
76 	char **nargv;		/* new argv list */
77 	int hflag = 0;
78 	int nargc = 0;		/* new argc */
79 	pid_t pid;		/* pid for fork */
80 	int retval;		/* exit status from exec'd commad */
81 	int showall = (argc <= 1);	/* show all resources */
82 	static char usage[] =
83 		"usage: %s [-F fstype] [-h] [-o fs_options ] [arg ...]\n";
84 
85 	cmd = strrchr(argv[0], '/');	/* find the basename */
86 	if (cmd)
87 		++cmd;
88 	else
89 		cmd = argv[0];
90 
91 	while ((c = getopt(argc, argv, "hF:o:")) != -1)
92 		switch (c) {
93 		case 'h':
94 			hflag = 1;	/* no header ... pass to subcommand */
95 			break;
96 		case 'F':
97 			err |= (fsname != NULL);	/* at most one -F */
98 			fsname = optarg;
99 			break;
100 		case 'o':		/* fs specific options */
101 			err |= (opts != NULL);	/* at most one -o */
102 			opts = optarg;
103 			break;
104 		case '?':
105 			err = 1;
106 			break;
107 		}
108 	if (err) {
109 		(void) fprintf(stderr, usage, cmd);
110 		exit(1);
111 	}
112 
113 	if ((dfp = fopen(DFSTYPES, "r")) == NULL) {
114 		(void) fprintf(stderr, "%s: cannot open %s\n", cmd, DFSTYPES);
115 		exit(1);
116 	}
117 
118 	/* allocate a block for the new argv list */
119 	if (!(nargv = (char **)malloc(sizeof (char *)*(argc-optind+ARGVPAD)))) {
120 		(void) fprintf(stderr, "%s: malloc failed.\n", cmd);
121 		exit(1);
122 	}
123 	nargv[nargc++] = cmd;
124 	if (hflag)
125 		nargv[nargc++] = "-h";
126 	if (opts) {
127 		nargv[nargc++] = "-o";
128 		nargv[nargc++] = opts;
129 	}
130 	for (; optind <= argc; ++optind)	/* this copies the last NULL */
131 		nargv[nargc++] = argv[optind];
132 
133 	if (showall) {		/* command with no args -- show all dfs's */
134 		while (fsname = getfs(dfp)) {
135 			(void) snprintf(subcmd, sizeof (subcmd),
136 			    FSCMD, fsname, cmd);
137 			switch (pid = fork()) {		/* do the subcommand */
138 			case 0:
139 				(void) execvp(subcmd, nargv);
140 				if (errno != ENOENT)
141 					perror(subcmd);
142 				_exit(1);
143 				/*NOTREACHED*/
144 			default:
145 				while (wait(&retval) != pid)
146 					;
147 				/* take exit status into account */
148 				err |= (retval & 0xff00) >> 8;
149 				break;
150 			case -1:
151 				(void) fprintf(stderr,
152 					"%s: fork failed - try again later.\n",
153 					cmd);
154 				exit(1);
155 			}
156 		}
157 		(void) fclose(dfp);
158 		if (pid == 0) {		/* we never got into the loop! */
159 			(void) fprintf(stderr,
160 				    "%s: no file systems in %s\n",
161 				    cmd, DFSTYPES);
162 			(void) fprintf(stderr, usage, cmd);
163 			exit(1);
164 		}
165 		else
166 			exit(err);
167 	}
168 
169 	if (fsname) {		/* generate fs specific command name */
170 		if (invalid(fsname, dfp)) {	/* valid ? */
171 			(void) fprintf(stderr,
172 				    "%s: invalid file system name\n", cmd);
173 			(void) fprintf(stderr, usage, cmd);
174 			exit(1);
175 		}
176 		else
177 			(void) snprintf(subcmd, sizeof (subcmd),
178 			    FSCMD, fsname, cmd);
179 	} else if (fsname = getfs(dfp))		/* use 1st line in dfstypes */
180 		(void) snprintf(subcmd, sizeof (subcmd), FSCMD, fsname, cmd);
181 	else {
182 		(void) fprintf(stderr,
183 			    "%s: no file systems in %s\n", cmd, DFSTYPES);
184 		(void) fprintf(stderr, usage, cmd);
185 		exit(1);
186 	}
187 
188 	(void) execvp(subcmd, nargv);
189 	perror(subcmd);				/* execvp failed */
190 	return (1);
191 }
192 
193 
194 /*
195  *	invalid(name, f)  -  return non-zero if name is not in
196  *			     the list of fs names in file f
197  */
198 
199 static int
200 invalid(const char *name,	/* file system name */
201 	FILE *f)		/* file of list of file system types */
202 {
203 	char *s;
204 
205 	while (s = getfs(f))	/* while there's still hope ... */
206 		if (strcmp(s, name) == 0)
207 			return (0);	/* we got it! */
208 	return (1);
209 }
210 
211 
212 /*
213  *   getfs(fp) - get the next file system name from fp
214  *               ignoring lines starting with a #.
215  *               All leading whitespace is discarded.
216  */
217 
218 static char buf[BUFSIZ];
219 
220 static char *
221 getfs(FILE *fp)
222 {
223 	register char *s;
224 
225 	while (s = fgets(buf, BUFSIZ, fp)) {
226 		while (isspace(*s))	/* leading whitespace doesn't count */
227 			++s;
228 		if (*s != '#') {	/* not a comment */
229 			char *t = s;
230 
231 			while (!isspace(*t))	/* get the token */
232 				++t;
233 			*t = '\0';		/* ignore rest of line */
234 			return (s);
235 		}
236 	}
237 	return (NULL);	/* that's all, folks! */
238 }
239