xref: /illumos-gate/usr/src/cmd/streams/strcmd/strconf.c (revision 08855964b9970604433f7b19dcd71cf5af5e5f14)
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 
23 /*
24  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
25  * Use is subject to license terms.
26  */
27 
28 /*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
29 /*	  All Rights Reserved  	*/
30 
31 /*
32  * Streams Command strconf:	display the configuration of the
33  *				stream associated with stdin.
34  *
35  * USAGE:	strconf
36  *    or:	strconf -m module
37  *    or:	strconf -t
38  *
39  * strconf with no options lists the modules on the stream.
40  * -m module	echos "yes" and returns 0 if the module is on the stream.
41  *		echos "no" and returns 2 if not.
42  * -t		lists only the topmost module.  returns 0 if there is a
43  *		module, 2 if not.
44  *
45  * RETURNS:
46  *	0	SUCCESS		it works
47  *	1	ERR_USAGE	bad invocation
48  *	2	ERR_MODULE	module not there
49  *	3	ERR_STDIN	an ioctl on the stdin stream failed
50  *	4	ERR_MEM		couldn't allocate memory
51  */
52 
53 #include	<stdio.h>
54 #include	<sys/stropts.h>
55 #include	<string.h>
56 #include	<stdlib.h>
57 #include	<unistd.h>
58 
59 #define	OPTLIST		"m:t"
60 #define	USAGE		"USAGE: %s [ -m module | -t ]\n"
61 
62 #define	SUCCESS		0
63 #define	FAILURE		1
64 
65 #define	ERR_USAGE	1	/* bad invocation			*/
66 #define	ERR_MODULE	2	/* module not there			*/
67 #define	ERR_STDIN	3	/* an ioctl on the stdin stream failed	*/
68 #define	ERR_MEM		4	/* couldn't allocate memory		*/
69 
70 #define	NMODULES	16	/* "reasonable" # of modules on a stream  */
71 				/* 	(there can be more)		  */
72 #define	MAXMODULES	2048	/* max # of modules			  */
73 
74 static char	*Cmd_namep;		/* how was it invoked?	*/
75 static int	more_modules(struct str_list *, int);
76 
77 int
78 main(int argc, char **argv)
79 {
80 	char		*modp;		/* ptr to module name		*/
81 	int		i;		/* loop var & junk (what else?)	*/
82 	boolean_t	mod_present;	/* B_TRUE if -m module		*/
83 	boolean_t	topmost;	/* B_TRUE if -t			*/
84 	struct str_mlist mlist[NMODULES]; /* modlist for strlist	*/
85 	struct str_list	strlist;	/* mods on stream		*/
86 
87 	/*
88 	 *	init
89 	 */
90 	Cmd_namep = argv[0];
91 	mod_present = topmost = B_FALSE;
92 	strlist.sl_nmods = NMODULES;
93 	strlist.sl_modlist = mlist;
94 
95 	/*
96 	 *	parse args
97 	 */
98 	if (argc > 1) {
99 		while ((i = getopt(argc, argv, OPTLIST)) != -1) {
100 			switch (i) {
101 			case 'm':	/* module present ? */
102 				modp = optarg;
103 				mod_present = B_TRUE;
104 				break;
105 
106 			case 't':	/* list topmost	*/
107 				topmost = B_TRUE;
108 				break;
109 
110 			default:
111 				(void) fprintf(stderr, USAGE, Cmd_namep);
112 				return (ERR_USAGE);
113 			}
114 		}
115 
116 		if (optind < argc) {
117 			(void) fprintf(stderr, USAGE, Cmd_namep);
118 			return (ERR_USAGE);
119 		}
120 	}
121 
122 	if (topmost && mod_present) {
123 		(void) fprintf(stderr,
124 		    "%s: [-t] and [-m] options cannot be used together\n",
125 		    Cmd_namep);
126 		(void) fprintf(stderr, USAGE, Cmd_namep);
127 		return (ERR_USAGE);
128 	}
129 
130 	/*
131 	 * get number of modules on stream
132 	 * allocate more room if needed
133 	 */
134 	if ((i = ioctl(STDIN_FILENO, I_LIST, NULL)) < 0) {
135 		perror("I_LIST");
136 		(void) fprintf(stderr,
137 			"%s: I_LIST ioctl failed\n", Cmd_namep);
138 		return (ERR_STDIN);
139 	}
140 	if (i > strlist.sl_nmods)
141 		if (more_modules(&strlist, i) != SUCCESS)
142 			return (ERR_MEM);
143 
144 	/*
145 	 *	get list of modules on stream
146 	 */
147 	strlist.sl_nmods = i;
148 	if (ioctl(STDIN_FILENO, I_LIST, &strlist) < 0) {
149 		perror("I_LIST");
150 		(void) fprintf(stderr, "%s: I_LIST ioctl failed\n", Cmd_namep);
151 		return (ERR_STDIN);
152 	}
153 
154 	/*
155 	 *	list topmost module
156 	 */
157 	if (topmost) {
158 		if (strlist.sl_nmods >= 2) {
159 			(void) puts(strlist.sl_modlist[0].l_name);
160 			return (SUCCESS);
161 		}
162 		return (ERR_MODULE);
163 	}
164 
165 	/*
166 	 *	check if module is present
167 	 */
168 	if (mod_present) {
169 		for (i = 0; i < strlist.sl_nmods; i++) {
170 			if (strncmp(modp, strlist.sl_modlist[i].l_name,
171 			    FMNAMESZ) == 0) {
172 				(void) puts("yes");
173 				return (SUCCESS);
174 			}
175 		}
176 		(void) puts("no");
177 		return (ERR_MODULE);
178 	}
179 
180 	/*
181 	 *	print names of all modules and topmost driver on stream
182 	 */
183 	for (i = 0; i < strlist.sl_nmods; i++)
184 		(void) puts(strlist.sl_modlist[i].l_name);
185 	return (SUCCESS);
186 }
187 
188 /*
189  * more_modules(listp, n)	allocate space for 'n' modules in 'listp'
190  *
191  * returns:	SUCCESS or FAILURE
192  */
193 
194 static int
195 more_modules(struct str_list *listp, int n)
196 {
197 	int			i;
198 	struct str_mlist	*modp;
199 
200 	if (n > MAXMODULES) {
201 		(void) fprintf(stderr,
202 		    "%s: too many modules (%d) -- max is %d\n",
203 		    Cmd_namep, n, MAXMODULES);
204 		return (FAILURE);
205 	}
206 
207 	if ((modp = calloc(n, sizeof (struct str_mlist))) == NULL) {
208 		perror("calloc");
209 		(void) fprintf(stderr,
210 		    "%s: failed to allocate space for module list\n",
211 		    Cmd_namep);
212 		return (FAILURE);
213 	}
214 
215 	for (i = 0; i < listp->sl_nmods; ++i)
216 		(void) strncpy(modp[i].l_name, listp->sl_modlist[i].l_name,
217 		    FMNAMESZ);
218 	listp->sl_nmods = n;
219 	listp->sl_modlist = modp;
220 	return (SUCCESS);
221 }
222