Home | History | Annotate | Line # | Download | only in net
nsdispatch.c revision 1.1.4.1 
      1 /*	$NetBSD: nsdispatch.c,v 1.1.4.1 1997/05/23 21:14:48 lukem Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 1997 Luke Mewburn <lukem (at) netbsd.org>
      5  * All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  * 3. All advertising materials mentioning features or use of this software
     16  *    must display the following acknowledgement:
     17  * 	This product includes software developed by Luke Mewburn.
     18  * 4. The name of the author may not be used to endorse or promote products
     19  *    derived from this software without specific prior written permission.
     20  *
     21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     22  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
     23  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     24  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
     25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
     26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
     27  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
     28  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
     29  * TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
     30  * USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     31  */
     32 
     33 #include <sys/types.h>
     34 #include <sys/param.h>
     35 #include <sys/stat.h>
     36 
     37 #include <fcntl.h>
     38 #include <stdio.h>
     39 #include <stdlib.h>
     40 #include <string.h>
     41 #include <unistd.h>
     42 
     43 #include "nsswitch.h"
     44 
     45 static int	  _nsmapsize = 0;
     46 static ns_DBT	 *_nsmap = NULL;
     47 /*
     48  * number of ns_DBT per chunk in _nsmap. calculated along the lines of
     49  *	NSELEMSPERCHUNK * sizeof(ns_DBT) < (1024 - some slop)
     50  * this is to help power of 2 mallocs which are really wasteful if the
     51  * amount just overflows a power of 2 boundary.
     52  */
     53 #define NSELEMSPERCHUNK		17
     54 
     55 int
     56 _nscmp(const void *a, const void *b)
     57 {
     58     return strncmp(((ns_DBT*)a)->name, ((ns_DBT *)b)->name, NS_MAXDBLEN);
     59 }
     60 
     61 void
     62 __nsdbput(dbt)
     63 	const ns_DBT *dbt;
     64 {
     65 	int	i;
     66 
     67 	for (i = 0; i < _nsmapsize; i++) {
     68 		if (_nscmp(dbt, &_nsmap[i]) == 0) {
     69 			memmove((void *)&_nsmap[i], (void *)dbt,
     70 				sizeof(ns_DBT));
     71 			return;
     72 		}
     73 	}
     74 
     75 	if ((_nsmapsize % NSELEMSPERCHUNK) == 0) {
     76 		_nsmap = realloc(_nsmap,
     77 			    (_nsmapsize + NSELEMSPERCHUNK) * sizeof(ns_DBT));
     78 		if (_nsmap == NULL)
     79 			_err(1, "nsdispatch: %m");
     80 
     81 	}
     82 	memmove((void *)&_nsmap[_nsmapsize++], (void *)dbt, sizeof(ns_DBT));
     83 }
     84 
     85 
     86 /*
     87  * __nsdbget --
     88  *	args: ns_DBT *dbt
     89  *	modifies: dbt
     90  *	looks for the element in dbt->name and finds from there
     91  *
     92  */
     93 void
     94 __nsdbget(dbt)
     95 	ns_DBT *dbt;
     96 {
     97 #ifdef NSLINEAR		/* XXX: just to compare linear vs bsearch */
     98 	int	i;
     99 	for (i = 0; i < _nsmapsize; i++) {
    100 		if (_nscmp(dbt, &_nsmap[i]) == 0) {
    101 			memmove((void *)dbt, (void *)&_nsmap[i],
    102 				sizeof(ns_DBT));
    103 			return;
    104 		}
    105 	}
    106 #else
    107 	ns_DBT *e;
    108 	e = bsearch(dbt, _nsmap, _nsmapsize, sizeof(ns_DBT), _nscmp);
    109 	if (e != NULL)
    110 		memmove((void *)dbt, (void *)e, sizeof(ns_DBT));
    111 #endif
    112 }
    113 
    114 
    115 void
    116 _nsdumpdbt(dbt)
    117 	const ns_DBT *dbt;
    118 {
    119 	int i;
    120 	printf("%s:\n", dbt->name);
    121 	for (i = 0; i < dbt->size; i++) {
    122 		int source = (dbt->map[i] & NS_SOURCEMASK);
    123 		int status = (dbt->map[i] & NS_STATUSMASK);
    124 
    125 		printf("  %2d: [%x] ", i, dbt->map[i]);
    126 		if (!dbt->map[i]) {
    127 		    printf(" (empty)\n");
    128 		    continue;
    129 		}
    130 		switch(source) {
    131 		case NS_FILES:		printf(" files"); break;
    132 		case NS_DNS:		printf(" dns"); break;
    133 		case NS_NIS:		printf(" nis"); break;
    134 		case NS_NISPLUS:	printf(" nisplus"); break;
    135 		case NS_COMPAT:		printf(" compat"); break;
    136 		default:		printf(" BADSOURCE(%x)", source); break;
    137 		}
    138 
    139 		if (!(status & NS_SUCCESS))
    140 			printf(" SUCCESS=continue");
    141 		if (status & NS_UNAVAIL)
    142 			printf(" UNAVAIL=return");
    143 		if (status & NS_NOTFOUND)
    144 			printf(" NOTFOUND=return");
    145 		if (status & NS_TRYAGAIN)
    146 			printf(" TRYAGAIN=return");
    147 		printf("\n");
    148 	}
    149 }
    150 
    151 
    152 void
    153 _nsgetdbt(src, dbt)
    154 	const char	*src;
    155 	ns_DBT		*dbt;
    156 {
    157 	static time_t	 confmod;
    158 	struct stat	 statbuf;
    159 
    160 	extern FILE 	*_nsyyin;
    161 	extern int	_nsyyparse();
    162 
    163 	strncpy(dbt->name, src, NS_MAXDBLEN);
    164 	dbt->name[NS_MAXDBLEN - 1] = '\0';
    165 	dbt->size = 1;
    166 	dbt->map[0] = NS_DEFAULTMAP;		/* default to 'files' */
    167 
    168 	if (confmod) {
    169 		if (stat(_PATH_NS_CONF, &statbuf) == -1)
    170 			return;
    171 		if (confmod < statbuf.st_mtime) {
    172 			free(_nsmap);
    173 			_nsmap = NULL;
    174 			_nsmapsize = 0;
    175 			confmod = 0;
    176 		}
    177 	}
    178 	if (!confmod) {
    179 		if (stat(_PATH_NS_CONF, &statbuf) == -1)
    180 			return;
    181 		_nsyyin = fopen(_PATH_NS_CONF, "r");
    182 		if (_nsyyin == NULL)
    183 			return;
    184 		_nsyyparse();
    185 #ifndef NSLINEAR
    186 		qsort(_nsmap, _nsmapsize, sizeof(ns_DBT), _nscmp);
    187 #endif
    188 		(void)fclose(_nsyyin);
    189 		confmod = statbuf.st_mtime;
    190 	}
    191 	__nsdbget(dbt);
    192 }
    193 
    194 
    195 int
    196 #if __STDC__
    197 nsdispatch(void *retval, ns_dtab disp_tab, const char *database, ...)
    198 #else
    199 nsdispatch(retval, disp_tab, database, va_alist)
    200 	void		*retval;
    201 	ns_dtab		 disp_tab;
    202 	const char	*database;
    203 	va_dcl
    204 #endif
    205 {
    206 	va_list	ap;
    207 	int	curdisp, result = 0;
    208 	ns_DBT	dbt;
    209 
    210 	_nsgetdbt(database, &dbt);
    211 
    212 #if NSDEBUG
    213 	_nsdumpdbt(&dbt);
    214 	fprintf(stderr, "nsdispatch: %s\n", database);
    215 #endif
    216 	for (curdisp = 0; curdisp < dbt.size; curdisp++) {
    217 		int source = (dbt.map[curdisp] & NS_SOURCEMASK);
    218 #if NSDEBUG
    219 		fprintf(stderr, "    %2d: source=%d", curdisp, source);
    220 #endif
    221 		if (source < 0 || source >= NS_MAXSOURCE)
    222 			continue;
    223 
    224 		result = 0;
    225 		if (disp_tab[source].cb) {
    226 #if __STDC__
    227 			va_start(ap, database);
    228 #else
    229 			va_start(ap);
    230 #endif
    231 			result = disp_tab[source].cb(retval,
    232 						disp_tab[source].cb_data, ap);
    233 			va_end(ap);
    234 #if NSDEBUG
    235 			fprintf(stderr, " result=%d (%d)", result,
    236 			    (result & (dbt.map[curdisp] & NS_STATUSMASK)));
    237 #endif
    238 			if (result & (dbt.map[curdisp] & NS_STATUSMASK)) {
    239 #if NSDEBUG
    240 				fprintf(stderr, " MATCH!\n");
    241 #endif
    242 				break;
    243 			}
    244 		}
    245 #if NSDEBUG
    246 		fprintf(stderr, "\n");
    247 #endif
    248 	}
    249 	return (result ? result : NS_NOTFOUND);
    250 }
    251