xref: /netbsd-src/lib/libc/net/nsdispatch.c (revision 4472dbe5e3bd91ef2540bada7a7ca7384627ff9b)
1 /*	$NetBSD: nsdispatch.c,v 1.16 2000/01/22 22:19:16 mycroft Exp $	*/
2 
3 /*-
4  * Copyright (c) 1997, 1998, 1999 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Luke Mewburn.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *        This product includes software developed by the NetBSD
21  *        Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 #include <sys/cdefs.h>
40 #if defined(LIBC_SCCS) && !defined(lint)
41 __RCSID("$NetBSD: nsdispatch.c,v 1.16 2000/01/22 22:19:16 mycroft Exp $");
42 #endif /* LIBC_SCCS and not lint */
43 
44 #include "namespace.h"
45 
46 #include <sys/types.h>
47 #include <sys/param.h>
48 #include <sys/stat.h>
49 
50 #include <assert.h>
51 #include <err.h>
52 #include <fcntl.h>
53 #define _NS_PRIVATE
54 #include <nsswitch.h>
55 #include <stdio.h>
56 #include <stdlib.h>
57 #include <string.h>
58 #include <unistd.h>
59 
60 #ifdef __STDC__
61 #include <stdarg.h>
62 #else
63 #include <varargs.h>
64 #endif
65 
66 #ifdef __weak_alias
67 __weak_alias(nsdispatch,_nsdispatch)
68 #endif
69 
70 
71 /*
72  * default sourcelist: `files'
73  */
74 const ns_src __nsdefaultsrc[] = {
75 	{ NSSRC_FILES, NS_SUCCESS },
76 	{ 0 },
77 };
78 
79 
80 static	int			 _nsmapsize = 0;
81 static	ns_dbt			*_nsmap = NULL;
82 
83 /*
84  * size of dynamic array chunk for _nsmap and _nsmap[x].srclist
85  */
86 #define NSELEMSPERCHUNK		8
87 
88 
89 int	_nscmp __P((const void *, const void *));
90 
91 
92 int
93 _nscmp(a, b)
94 	const void *a;
95 	const void *b;
96 {
97 	return (strcasecmp(((const ns_dbt *)a)->name,
98 	    ((const ns_dbt *)b)->name));
99 }
100 
101 
102 int
103 _nsdbtaddsrc(dbt, src)
104 	ns_dbt		*dbt;
105 	const ns_src	*src;
106 {
107 
108 	_DIAGASSERT(dbt != NULL);
109 	_DIAGASSERT(src != NULL);
110 
111 	if ((dbt->srclistsize % NSELEMSPERCHUNK) == 0) {
112 		ns_src *new;
113 
114 		new = (ns_src *)realloc(dbt->srclist,
115 		    (dbt->srclistsize + NSELEMSPERCHUNK) * sizeof(ns_src));
116 		if (new == NULL)
117 			return (-1);
118 		dbt->srclist = new;
119 	}
120 	memmove(&dbt->srclist[dbt->srclistsize++], src, sizeof(ns_src));
121 	return (0);
122 }
123 
124 
125 void
126 _nsdbtdump(dbt)
127 	const ns_dbt *dbt;
128 {
129 	int i;
130 
131 	_DIAGASSERT(dbt != NULL);
132 
133 	printf("%s (%d source%s):", dbt->name, dbt->srclistsize,
134 	    dbt->srclistsize == 1 ? "" : "s");
135 	for (i = 0; i < dbt->srclistsize; i++) {
136 		printf(" %s", dbt->srclist[i].name);
137 		if (!(dbt->srclist[i].flags &
138 		    (NS_UNAVAIL|NS_NOTFOUND|NS_TRYAGAIN)) &&
139 		    (dbt->srclist[i].flags & NS_SUCCESS))
140 			continue;
141 		printf(" [");
142 		if (!(dbt->srclist[i].flags & NS_SUCCESS))
143 			printf(" SUCCESS=continue");
144 		if (dbt->srclist[i].flags & NS_UNAVAIL)
145 			printf(" UNAVAIL=return");
146 		if (dbt->srclist[i].flags & NS_NOTFOUND)
147 			printf(" NOTFOUND=return");
148 		if (dbt->srclist[i].flags & NS_TRYAGAIN)
149 			printf(" TRYAGAIN=return");
150 		printf(" ]");
151 	}
152 	printf("\n");
153 }
154 
155 
156 const ns_dbt *
157 _nsdbtget(name)
158 	const char	*name;
159 {
160 	static	time_t	 confmod;
161 
162 	struct stat	 statbuf;
163 	ns_dbt		 dbt;
164 
165 	extern	FILE 	*_nsyyin;
166 	extern	int	 _nsyyparse __P((void));
167 
168 	_DIAGASSERT(name != NULL);
169 
170 	dbt.name = name;
171 
172 	if (confmod) {
173 		if (stat(_PATH_NS_CONF, &statbuf) == -1)
174 			return (NULL);
175 		if (confmod < statbuf.st_mtime) {
176 			int i, j;
177 
178 			for (i = 0; i < _nsmapsize; i++) {
179 				for (j = 0; j < _nsmap[i].srclistsize; j++) {
180 					if (_nsmap[i].srclist[j].name != NULL) {
181 						/*LINTED const cast*/
182 						free((void *)
183 						    _nsmap[i].srclist[j].name);
184 					}
185 				}
186 				if (_nsmap[i].srclist)
187 					free(_nsmap[i].srclist);
188 				if (_nsmap[i].name) {
189 					/*LINTED const cast*/
190 					free((void *)_nsmap[i].name);
191 				}
192 			}
193 			if (_nsmap)
194 				free(_nsmap);
195 			_nsmap = NULL;
196 			_nsmapsize = 0;
197 			confmod = 0;
198 		}
199 	}
200 	if (!confmod) {
201 		if (stat(_PATH_NS_CONF, &statbuf) == -1)
202 			return (NULL);
203 		_nsyyin = fopen(_PATH_NS_CONF, "r");
204 		if (_nsyyin == NULL)
205 			return (NULL);
206 		_nsyyparse();
207 		(void)fclose(_nsyyin);
208 		qsort(_nsmap, (size_t)_nsmapsize, sizeof(ns_dbt), _nscmp);
209 		confmod = statbuf.st_mtime;
210 	}
211 	return (bsearch(&dbt, _nsmap, (size_t)_nsmapsize, sizeof(ns_dbt),
212 	    _nscmp));
213 }
214 
215 
216 int
217 _nsdbtput(dbt)
218 	const ns_dbt *dbt;
219 {
220 	int	i;
221 
222 	_DIAGASSERT(dbt != NULL);
223 
224 	for (i = 0; i < _nsmapsize; i++) {
225 		if (_nscmp(dbt, &_nsmap[i]) == 0) {
226 					/* overwrite existing entry */
227 			if (_nsmap[i].srclist != NULL)
228 				free(_nsmap[i].srclist);
229 			memmove(&_nsmap[i], dbt, sizeof(ns_dbt));
230 			return (0);
231 		}
232 	}
233 
234 	if ((_nsmapsize % NSELEMSPERCHUNK) == 0) {
235 		ns_dbt *new;
236 
237 		new = (ns_dbt *)realloc(_nsmap,
238 		    (_nsmapsize + NSELEMSPERCHUNK) * sizeof(ns_dbt));
239 		if (new == NULL)
240 			return (-1);
241 		_nsmap = new;
242 	}
243 	memmove(&_nsmap[_nsmapsize++], dbt, sizeof(ns_dbt));
244 	return (0);
245 }
246 
247 
248 int
249 /*ARGSUSED*/
250 #if __STDC__
251 nsdispatch(void *retval, const ns_dtab disp_tab[], const char *database,
252 	    const char *method, const ns_src defaults[], ...)
253 #else
254 nsdispatch(retval, disp_tab, database, method, defaults, va_alist)
255 	void		*retval;
256 	const ns_dtab	 disp_tab[];
257 	const char	*database;
258 	const char	*method;
259 	const ns_src	 defaults[];
260 	va_dcl
261 #endif
262 {
263 	va_list		 ap;
264 	int		 i, curdisp, result;
265 	const ns_dbt	*dbt;
266 	const ns_src	*srclist;
267 	int		 srclistsize;
268 
269 	_DIAGASSERT(database != NULL);
270 	_DIAGASSERT(method != NULL);
271 	if (database == NULL || method == NULL)
272 		return (NS_UNAVAIL);
273 
274 	dbt = _nsdbtget(database);
275 	if (dbt != NULL) {
276 		srclist = dbt->srclist;
277 		srclistsize = dbt->srclistsize;
278 	} else {
279 		srclist = defaults;
280 		srclistsize = 0;
281 		while (srclist[srclistsize].name != NULL)
282 			srclistsize++;
283 	}
284 	result = 0;
285 
286 	for (i = 0; i < srclistsize; i++) {
287 		for (curdisp = 0; disp_tab[curdisp].src != NULL; curdisp++)
288 			if (strcasecmp(disp_tab[curdisp].src,
289 			    srclist[i].name) == 0)
290 				break;
291 		result = 0;
292 		if (disp_tab[curdisp].callback) {
293 #if __STDC__
294 			va_start(ap, defaults);
295 #else
296 			va_start(ap);
297 #endif
298 			result = disp_tab[curdisp].callback(retval,
299 			    disp_tab[curdisp].cb_data, ap);
300 			va_end(ap);
301 			if (result & srclist[i].flags) {
302 				break;
303 			}
304 		}
305 	}
306 	return (result ? result : NS_NOTFOUND);
307 }
308