xref: /netbsd-src/lib/libc/net/nsdispatch.c (revision 3b435a73967be44dfb4a27315acd72bfacde430c)
1 /*	$NetBSD: nsdispatch.c,v 1.14 1999/09/20 04:39:16 lukem 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 1.14 1999/09/20 04:39:16 lukem 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 void
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 		dbt->srclist = (ns_src *)realloc(dbt->srclist,
113 		    (dbt->srclistsize + NSELEMSPERCHUNK) * sizeof(ns_src));
114 		if (dbt->srclist == NULL)
115 			err(1, "nsdispatch: memory allocation failure");
116 	}
117 	memmove(&dbt->srclist[dbt->srclistsize++], src, sizeof(ns_src));
118 }
119 
120 
121 void
122 _nsdbtdump(dbt)
123 	const ns_dbt *dbt;
124 {
125 	int i;
126 
127 	_DIAGASSERT(dbt != NULL);
128 
129 	printf("%s (%d source%s):", dbt->name, dbt->srclistsize,
130 	    dbt->srclistsize == 1 ? "" : "s");
131 	for (i = 0; i < dbt->srclistsize; i++) {
132 		printf(" %s", dbt->srclist[i].name);
133 		if (!(dbt->srclist[i].flags &
134 		    (NS_UNAVAIL|NS_NOTFOUND|NS_TRYAGAIN)) &&
135 		    (dbt->srclist[i].flags & NS_SUCCESS))
136 			continue;
137 		printf(" [");
138 		if (!(dbt->srclist[i].flags & NS_SUCCESS))
139 			printf(" SUCCESS=continue");
140 		if (dbt->srclist[i].flags & NS_UNAVAIL)
141 			printf(" UNAVAIL=return");
142 		if (dbt->srclist[i].flags & NS_NOTFOUND)
143 			printf(" NOTFOUND=return");
144 		if (dbt->srclist[i].flags & NS_TRYAGAIN)
145 			printf(" TRYAGAIN=return");
146 		printf(" ]");
147 	}
148 	printf("\n");
149 }
150 
151 
152 const ns_dbt *
153 _nsdbtget(name)
154 	const char	*name;
155 {
156 	static	time_t	 confmod;
157 
158 	struct stat	 statbuf;
159 	ns_dbt		 dbt;
160 
161 	extern	FILE 	*_nsyyin;
162 	extern	int	 _nsyyparse __P((void));
163 
164 	_DIAGASSERT(name != NULL);
165 
166 	dbt.name = name;
167 
168 	if (confmod) {
169 		if (stat(_PATH_NS_CONF, &statbuf) == -1)
170 			return (NULL);
171 		if (confmod < statbuf.st_mtime) {
172 			int i, j;
173 
174 			for (i = 0; i < _nsmapsize; i++) {
175 				for (j = 0; j < _nsmap[i].srclistsize; j++) {
176 					if (_nsmap[i].srclist[j].name != NULL) {
177 						/*LINTED const cast*/
178 						free((void *)
179 						    _nsmap[i].srclist[j].name);
180 					}
181 				}
182 				if (_nsmap[i].srclist)
183 					free(_nsmap[i].srclist);
184 				if (_nsmap[i].name) {
185 					/*LINTED const cast*/
186 					free((void *)_nsmap[i].name);
187 				}
188 			}
189 			if (_nsmap)
190 				free(_nsmap);
191 			_nsmap = NULL;
192 			_nsmapsize = 0;
193 			confmod = 0;
194 		}
195 	}
196 	if (!confmod) {
197 		if (stat(_PATH_NS_CONF, &statbuf) == -1)
198 			return (NULL);
199 		_nsyyin = fopen(_PATH_NS_CONF, "r");
200 		if (_nsyyin == NULL)
201 			return (NULL);
202 		_nsyyparse();
203 		(void)fclose(_nsyyin);
204 		qsort(_nsmap, (size_t)_nsmapsize, sizeof(ns_dbt), _nscmp);
205 		confmod = statbuf.st_mtime;
206 	}
207 	return (bsearch(&dbt, _nsmap, (size_t)_nsmapsize, sizeof(ns_dbt),
208 	    _nscmp));
209 }
210 
211 
212 void
213 _nsdbtput(dbt)
214 	const ns_dbt *dbt;
215 {
216 	int	i;
217 
218 	_DIAGASSERT(dbt != NULL);
219 
220 	for (i = 0; i < _nsmapsize; i++) {
221 		if (_nscmp(dbt, &_nsmap[i]) == 0) {
222 					/* overwrite existing entry */
223 			if (_nsmap[i].srclist != NULL)
224 				free(_nsmap[i].srclist);
225 			memmove(&_nsmap[i], dbt, sizeof(ns_dbt));
226 			return;
227 		}
228 	}
229 
230 	if ((_nsmapsize % NSELEMSPERCHUNK) == 0) {
231 		_nsmap = (ns_dbt *)realloc(_nsmap,
232 		    (_nsmapsize + NSELEMSPERCHUNK) * sizeof(ns_dbt));
233 		if (_nsmap == NULL)
234 			err(1, "nsdispatch: memory allocation failure");
235 	}
236 	memmove(&_nsmap[_nsmapsize++], dbt, sizeof(ns_dbt));
237 }
238 
239 
240 int
241 /*ARGSUSED*/
242 #if __STDC__
243 nsdispatch(void *retval, const ns_dtab disp_tab[], const char *database,
244 	    const char *method, const ns_src defaults[], ...)
245 #else
246 nsdispatch(retval, disp_tab, database, method, defaults, va_alist)
247 	void		*retval;
248 	const ns_dtab	 disp_tab[];
249 	const char	*database;
250 	const char	*method;
251 	const ns_src	 defaults[];
252 	va_dcl
253 #endif
254 {
255 	va_list		 ap;
256 	int		 i, curdisp, result;
257 	const ns_dbt	*dbt;
258 	const ns_src	*srclist;
259 	int		 srclistsize;
260 
261 	_DIAGASSERT(database != NULL);
262 	_DIAGASSERT(method != NULL);
263 	if (database == NULL || method == NULL)
264 		return (NS_UNAVAIL);
265 
266 	dbt = _nsdbtget(database);
267 	if (dbt != NULL) {
268 		srclist = dbt->srclist;
269 		srclistsize = dbt->srclistsize;
270 	} else {
271 		srclist = defaults;
272 		srclistsize = 0;
273 		while (srclist[srclistsize].name != NULL)
274 			srclistsize++;
275 	}
276 	result = 0;
277 
278 	for (i = 0; i < srclistsize; i++) {
279 		for (curdisp = 0; disp_tab[curdisp].src != NULL; curdisp++)
280 			if (strcasecmp(disp_tab[curdisp].src,
281 			    srclist[i].name) == 0)
282 				break;
283 		result = 0;
284 		if (disp_tab[curdisp].callback) {
285 #if __STDC__
286 			va_start(ap, defaults);
287 #else
288 			va_start(ap);
289 #endif
290 			result = disp_tab[curdisp].callback(retval,
291 			    disp_tab[curdisp].cb_data, ap);
292 			va_end(ap);
293 			if (result & srclist[i].flags) {
294 				break;
295 			}
296 		}
297 	}
298 	return (result ? result : NS_NOTFOUND);
299 }
300