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nsdispatch.c revision 1.18 
      1 /*	$NetBSD: nsdispatch.c,v 1.18 2002/05/26 14:48:19 wiz 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 1.18 2002/05/26 14:48:19 wiz 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 <stdarg.h>
     56 #include <stdio.h>
     57 #include <stdlib.h>
     58 #include <string.h>
     59 #include <unistd.h>
     60 
     61 extern	FILE 	*_nsyyin;
     62 extern	int	 _nsyyparse __P((void));
     63 
     64 
     65 #ifdef __weak_alias
     66 __weak_alias(nsdispatch,_nsdispatch)
     67 #endif
     68 
     69 
     70 /*
     71  * default sourcelist: `files'
     72  */
     73 const ns_src __nsdefaultsrc[] = {
     74 	{ NSSRC_FILES, NS_SUCCESS },
     75 	{ 0 },
     76 };
     77 
     78 
     79 static	int			 _nsmapsize = 0;
     80 static	ns_dbt			*_nsmap = NULL;
     81 
     82 /*
     83  * size of dynamic array chunk for _nsmap and _nsmap[x].srclist
     84  */
     85 #define NSELEMSPERCHUNK		8
     86 
     87 
     88 int	_nscmp __P((const void *, const void *));
     89 
     90 
     91 int
     92 _nscmp(a, b)
     93 	const void *a;
     94 	const void *b;
     95 {
     96 	return (strcasecmp(((const ns_dbt *)a)->name,
     97 	    ((const ns_dbt *)b)->name));
     98 }
     99 
    100 
    101 int
    102 _nsdbtaddsrc(dbt, src)
    103 	ns_dbt		*dbt;
    104 	const ns_src	*src;
    105 {
    106 
    107 	_DIAGASSERT(dbt != NULL);
    108 	_DIAGASSERT(src != NULL);
    109 
    110 	if ((dbt->srclistsize % NSELEMSPERCHUNK) == 0) {
    111 		ns_src *new;
    112 
    113 		new = (ns_src *)realloc(dbt->srclist,
    114 		    (dbt->srclistsize + NSELEMSPERCHUNK) * sizeof(ns_src));
    115 		if (new == NULL)
    116 			return (-1);
    117 		dbt->srclist = new;
    118 	}
    119 	memmove(&dbt->srclist[dbt->srclistsize++], src, sizeof(ns_src));
    120 	return (0);
    121 }
    122 
    123 
    124 void
    125 _nsdbtdump(dbt)
    126 	const ns_dbt *dbt;
    127 {
    128 	int i;
    129 
    130 	_DIAGASSERT(dbt != NULL);
    131 
    132 	printf("%s (%d source%s):", dbt->name, dbt->srclistsize,
    133 	    dbt->srclistsize == 1 ? "" : "s");
    134 	for (i = 0; i < dbt->srclistsize; i++) {
    135 		printf(" %s", dbt->srclist[i].name);
    136 		if (!(dbt->srclist[i].flags &
    137 		    (NS_UNAVAIL|NS_NOTFOUND|NS_TRYAGAIN)) &&
    138 		    (dbt->srclist[i].flags & NS_SUCCESS))
    139 			continue;
    140 		printf(" [");
    141 		if (!(dbt->srclist[i].flags & NS_SUCCESS))
    142 			printf(" SUCCESS=continue");
    143 		if (dbt->srclist[i].flags & NS_UNAVAIL)
    144 			printf(" UNAVAIL=return");
    145 		if (dbt->srclist[i].flags & NS_NOTFOUND)
    146 			printf(" NOTFOUND=return");
    147 		if (dbt->srclist[i].flags & NS_TRYAGAIN)
    148 			printf(" TRYAGAIN=return");
    149 		printf(" ]");
    150 	}
    151 	printf("\n");
    152 }
    153 
    154 
    155 const ns_dbt *
    156 _nsdbtget(name)
    157 	const char	*name;
    158 {
    159 	static	time_t	 confmod;
    160 
    161 	struct stat	 statbuf;
    162 	ns_dbt		 dbt;
    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 int
    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 (0);
    227 		}
    228 	}
    229 
    230 	if ((_nsmapsize % NSELEMSPERCHUNK) == 0) {
    231 		ns_dbt *new;
    232 
    233 		new = (ns_dbt *)realloc(_nsmap,
    234 		    (_nsmapsize + NSELEMSPERCHUNK) * sizeof(ns_dbt));
    235 		if (new == NULL)
    236 			return (-1);
    237 		_nsmap = new;
    238 	}
    239 	memmove(&_nsmap[_nsmapsize++], dbt, sizeof(ns_dbt));
    240 	return (0);
    241 }
    242 
    243 
    244 int
    245 /*ARGSUSED*/
    246 nsdispatch(void *retval, const ns_dtab disp_tab[], const char *database,
    247 	    const char *method, const ns_src defaults[], ...)
    248 {
    249 	va_list		 ap;
    250 	int		 i, curdisp, result;
    251 	const ns_dbt	*dbt;
    252 	const ns_src	*srclist;
    253 	int		 srclistsize;
    254 
    255 	_DIAGASSERT(database != NULL);
    256 	_DIAGASSERT(method != NULL);
    257 	if (database == NULL || method == NULL)
    258 		return (NS_UNAVAIL);
    259 
    260 	dbt = _nsdbtget(database);
    261 	if (dbt != NULL) {
    262 		srclist = dbt->srclist;
    263 		srclistsize = dbt->srclistsize;
    264 	} else {
    265 		srclist = defaults;
    266 		srclistsize = 0;
    267 		while (srclist[srclistsize].name != NULL)
    268 			srclistsize++;
    269 	}
    270 	result = 0;
    271 
    272 	for (i = 0; i < srclistsize; i++) {
    273 		for (curdisp = 0; disp_tab[curdisp].src != NULL; curdisp++)
    274 			if (strcasecmp(disp_tab[curdisp].src,
    275 			    srclist[i].name) == 0)
    276 				break;
    277 		result = 0;
    278 		if (disp_tab[curdisp].callback) {
    279 			va_start(ap, defaults);
    280 			result = disp_tab[curdisp].callback(retval,
    281 			    disp_tab[curdisp].cb_data, ap);
    282 			va_end(ap);
    283 			if (result & srclist[i].flags) {
    284 				break;
    285 			}
    286 		}
    287 	}
    288 	return (result ? result : NS_NOTFOUND);
    289 }
    290