xref: /titanic_52/usr/src/cmd/fs.d/nfs/lib/sharetab.c (revision 74e20cfe817b82802b16fac8690dadcda76f54f5)
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  * Copyright 1999 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*	Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T	*/
28 /*	  All Rights Reserved  	*/
29 
30 /*
31  * Portions of this source code were derived from Berkeley 4.3 BSD
32  * under license from the Regents of the University of California.
33  */
34 
35 #pragma ident	"%Z%%M%	%I%	%E% SMI"
36 
37 #include <stdio.h>
38 #include <stdlib.h>
39 #include <string.h>
40 #include <unistd.h>
41 #include "sharetab.h"
42 
43 static int logging_specified(char *);
44 
45 /*
46  * Get an entry from the share table.
47  * There should be at least 4 fields:
48  *
49  * 	pathname  resource  fstype  options  [ description ]
50  *
51  * A fifth field (description) is optional.
52  *
53  * Returns:
54  *	> 1  valid entry
55  *	= 0  end of file
56  *	< 0  error
57  */
58 int
59 getshare(fd, shp)
60 	FILE *fd;
61 	struct share **shp;
62 {
63 	static char *line = NULL;
64 	static struct share *sh = NULL;
65 	char *p;
66 	char *lasts;
67 	char *w = " \t";
68 
69 	if (line == NULL) {
70 		line = (char *)malloc(MAXBUFSIZE+1);
71 		if (line == NULL)
72 			return (-1);
73 	}
74 	if (sh == NULL) {
75 		sh = (struct share *)malloc(sizeof (*sh));
76 		if (sh == NULL)
77 			return (-1);
78 	}
79 
80 	p = fgets(line, MAXBUFSIZE, fd);
81 	if (p == NULL)
82 		return (0);
83 	line[strlen(line) - 1] = '\0';
84 
85 	sh->sh_path = (char *)strtok_r(p, w, &lasts);
86 	if (sh->sh_path == NULL)
87 		return (-3);
88 	sh->sh_res = (char *)strtok_r(NULL, w, &lasts);
89 	if (sh->sh_res == NULL)
90 		return (-3);
91 	sh->sh_fstype = (char *)strtok_r(NULL, w, &lasts);
92 	if (sh->sh_fstype == NULL)
93 		return (-3);
94 	sh->sh_opts = (char *)strtok_r(NULL, w, &lasts);
95 	if (sh->sh_opts == NULL)
96 		return (-3);
97 	sh->sh_descr = (char *)strtok_r(NULL, "", &lasts);
98 	if (sh->sh_descr == NULL)
99 		sh->sh_descr = "";
100 
101 	*shp = sh;
102 	return (1);
103 }
104 
105 /*
106  * Append an entry to the sharetab file.
107  */
108 int
109 putshare(fd, sh)
110 	FILE *fd;
111 	struct share *sh;
112 {
113 	int r;
114 
115 	if (fseek(fd, 0L, 2) < 0)
116 		return (-1);
117 
118 	r = fprintf(fd, "%s\t%s\t%s\t%s\t%s\n",
119 		sh->sh_path,
120 		sh->sh_res,
121 		sh->sh_fstype,
122 		sh->sh_opts,
123 		sh->sh_descr);
124 	return (r);
125 }
126 
127 /*
128  * The entry corresponding to path is removed from the
129  * sharetab file.  The file is assumed to be locked.
130  * Read the entries into a linked list of share structures
131  * minus the entry to be removed.  Then truncate the sharetab
132  * file and write almost all of it back to the file from the
133  * linked list.
134  *
135  * If logging information is requested then 'logging' is set
136  * to non-zero if the entry is shared with logging enabled.
137  *
138  * Note: The file is assumed to be locked.
139  */
140 int
141 remshare(fd, path, logging)
142 	FILE *fd;
143 	char *path;
144 	int *logging;
145 {
146 	struct share *sh_tmp;
147 	struct shl {			/* the linked list */
148 		struct shl   *shl_next;
149 		struct share *shl_sh;
150 	};
151 	struct shl *shl_head = NULL;
152 	struct shl *shl, *prev, *next;
153 	int res, remcnt;
154 
155 	rewind(fd);
156 	remcnt = 0;
157 	shl = NULL;
158 	while ((res = getshare(fd, &sh_tmp)) > 0) {
159 		if (strcmp(path, sh_tmp->sh_path) == 0 ||
160 		    strcmp(path, sh_tmp->sh_res)  == 0) {
161 			remcnt++;
162 			if (logging != NULL)
163 				*logging = logging_specified(sh_tmp->sh_opts);
164 		} else {
165 			prev = shl;
166 			shl = (struct shl *)malloc(sizeof (*shl));
167 			if (shl == NULL) {
168 				res = -1;
169 				goto dealloc;
170 			}
171 			if (shl_head == NULL)
172 				shl_head = shl;
173 			else
174 				prev->shl_next = shl;
175 			shl->shl_next = NULL;
176 			shl->shl_sh = sharedup(sh_tmp);
177 			if (shl->shl_sh == NULL) {
178 				res = -3;
179 				goto dealloc;
180 			}
181 		}
182 	}
183 	if (res < 0)
184 		goto dealloc;
185 	if (remcnt == 0) {
186 		res = 1;	/* nothing removed */
187 		goto dealloc;
188 	}
189 
190 	if (ftruncate(fileno(fd), 0) < 0) {
191 		res = -2;
192 		goto dealloc;
193 	}
194 
195 	for (shl = shl_head; shl; shl = shl->shl_next)
196 		putshare(fd, shl->shl_sh);
197 	res = 1;
198 
199 dealloc:
200 	for (shl = shl_head; shl; shl = next) {
201 		/*
202 		 * make sure we don't reference sharefree with NULL shl->shl_sh
203 		 */
204 		if (shl->shl_sh != NULL)
205 			sharefree(shl->shl_sh);
206 		next = shl->shl_next;
207 		free(shl);
208 	}
209 	return (res);
210 }
211 
212 struct share *
213 sharedup(sh)
214 	struct share *sh;
215 {
216 	struct share *nsh;
217 
218 	nsh = (struct share *)malloc(sizeof (*nsh));
219 	if (nsh == NULL)
220 		return (NULL);
221 
222 	(void) memset((char *)nsh, 0, sizeof (*nsh));
223 	if (sh->sh_path) {
224 		nsh->sh_path = strdup(sh->sh_path);
225 		if (nsh->sh_path == NULL)
226 			goto alloc_failed;
227 	}
228 
229 	if (sh->sh_res) {
230 		nsh->sh_res = strdup(sh->sh_res);
231 		if (nsh->sh_res == NULL)
232 			goto alloc_failed;
233 	}
234 	if (sh->sh_fstype) {
235 		nsh->sh_fstype = strdup(sh->sh_fstype);
236 		if (nsh->sh_fstype == NULL)
237 			goto alloc_failed;
238 	}
239 	if (sh->sh_opts) {
240 		nsh->sh_opts = strdup(sh->sh_opts);
241 		if (nsh->sh_opts == NULL)
242 			goto alloc_failed;
243 	}
244 	if (sh->sh_descr) {
245 		nsh->sh_descr = strdup(sh->sh_descr);
246 		if (nsh->sh_descr == NULL)
247 			goto alloc_failed;
248 	}
249 	return (nsh);
250 
251 alloc_failed:
252 	sharefree(nsh);
253 	return (NULL);
254 }
255 
256 void
257 sharefree(sh)
258 	struct share *sh;
259 {
260 	if (sh->sh_path != NULL)
261 		free(sh->sh_path);
262 	if (sh->sh_res != NULL)
263 		free(sh->sh_res);
264 	if (sh->sh_fstype != NULL)
265 		free(sh->sh_fstype);
266 	if (sh->sh_opts != NULL)
267 		free(sh->sh_opts);
268 	if (sh->sh_descr != NULL)
269 		free(sh->sh_descr);
270 	free(sh);
271 }
272 
273 /*
274  * Return the value after "=" for option "opt"
275  * in option string "optlist". Caller must
276  * free returned value.
277  */
278 char *
279 getshareopt(optlist, opt)
280 	char *optlist, *opt;
281 {
282 	char *p, *pe;
283 	char *b;
284 	char *bb;
285 	char *lasts;
286 	char *val = NULL;
287 
288 	b = bb = strdup(optlist);
289 	if (b == NULL)
290 		return (NULL);
291 
292 	while (p = (char *)strtok_r(b, ",", &lasts)) {
293 		b = NULL;
294 		if (pe = strchr(p, '=')) {
295 			*pe = '\0';
296 			if (strcmp(opt, p) == 0) {
297 				val = strdup(pe + 1);
298 				goto done;
299 			}
300 		}
301 		if (strcmp(opt, p) == 0) {
302 			val = strdup("");
303 			goto done;
304 		}
305 	}
306 done:
307 	free(bb);
308 	return (val);
309 }
310 
311 /*
312  * Return 1 if the "log" option was specified in the optlist.
313  * Return 0 otherwise.
314  */
315 static int
316 logging_specified(optlist)
317 	char *optlist;
318 {
319 	char *p;
320 	char *b, *bb, *lasts;
321 	int specified = 0;
322 
323 	b = bb = strdup(optlist);
324 	if (b == NULL)
325 		return (0);
326 
327 	while (p = (char *)strtok_r(b, ",", &lasts)) {
328 		b = NULL;
329 		if (strncmp(p, "log", 3) == 0)
330 			specified++;
331 	}
332 
333 	free(bb);
334 	return (specified ? 1 : 0);
335 }
336