xref: /src/lib/libc/net/nsdispatch.c

/*	$NetBSD: nsdispatch.c,v 1.2 1999/01/15 12:53:24 lukem Exp $	*/

/*-
 * Copyright (c) 1997, 1998, 1999 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Luke Mewburn.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *        This product includes software developed by the NetBSD
 *        Foundation, Inc. and its contributors.
 * 4. Neither the name of The NetBSD Foundation nor the names of its
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include <sys/types.h>
#include <sys/param.h>
#include <sys/stat.h>

#include <err.h>
#include <fcntl.h>
#define _NS_PRIVATE
#define _PATH_NS_CONF "/tmp/nsswitch.conf"
#include <nsswitch.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>


static	int			 _nsmapsize = 0;
static	ns_dbt			*_nsmap = NULL;

/*
 * size of dynamic array chunk for _nsmap and _nsmap[x].srclist
 */
#define NSELEMSPERCHUNK		8


int	_nscmp __P((const void *, const void *));


int
_nscmp(a, b)
	const void *a;
	const void *b;
{
	return (strcasecmp(((ns_dbt *)a)->name, ((ns_dbt *)b)->name));
}


void
_nsdbtaddsrc(dbt, src)
	ns_dbt		*dbt;
	const ns_src	*src;
{
	if ((dbt->srclistsize % NSELEMSPERCHUNK) == 0) {
		dbt->srclist = (ns_src *)realloc(dbt->srclist,
		    (dbt->srclistsize + NSELEMSPERCHUNK) * sizeof(ns_src));
		if (dbt->srclist == NULL)
			err(1, "nsdispatch: memory allocation failure");
	}
	memmove((void *)&dbt->srclist[dbt->srclistsize++], (void *)src,
	    sizeof(ns_src));
}


void
_nsdbtdump(dbt)
	const ns_dbt *dbt;
{
	int i;

	printf("%s (%d source%s):", dbt->name, dbt->srclistsize,
	    dbt->srclistsize == 1 ? "" : "s");
	for (i = 0; i < dbt->srclistsize; i++) {
		printf(" %s", dbt->srclist[i].name);
		if (!(dbt->srclist[i].flags &
		    (NS_UNAVAIL|NS_NOTFOUND|NS_TRYAGAIN)) &&
		    (dbt->srclist[i].flags & NS_SUCCESS))
			continue;
		printf(" [");
		if (!(dbt->srclist[i].flags & NS_SUCCESS))
			printf(" SUCCESS=continue");
		if (dbt->srclist[i].flags & NS_UNAVAIL)
			printf(" UNAVAIL=return");
		if (dbt->srclist[i].flags & NS_NOTFOUND)
			printf(" NOTFOUND=return");
		if (dbt->srclist[i].flags & NS_TRYAGAIN)
			printf(" TRYAGAIN=return");
		printf(" ]");
	}
	printf("\n");
}


const ns_dbt *
_nsdbtget(name)
	const char	*name;
{
	static	time_t	 confmod;
	static	ns_dbt	 dbt;

	struct stat	 statbuf;
	ns_dbt		*ndbt;

	extern	FILE 	*_nsyyin;
	extern	int	 _nsyyparse __P((void));

	if (dbt.name == NULL) {		/* construct dummy `files' entry */
		ns_src	src;

		src.name = NSSRC_FILES;
		src.flags = NS_SUCCESS;
		dbt.name = name;
		_nsdbtaddsrc(&dbt, &src);
	}

	if (confmod) {
		if (stat(_PATH_NS_CONF, &statbuf) == -1)
			return (&dbt);
		if (confmod < statbuf.st_mtime) {
			int i, j;

			for (i = 0; i < _nsmapsize; i++) {
				for (j = 0; j < _nsmap[i].srclistsize; j++) {
					if (_nsmap[i].srclist[j].name != NULL)
						free((char *)
						    _nsmap[i].srclist[j].name);
				}
				if (_nsmap[i].srclist)
					free(_nsmap[i].srclist);
				if (_nsmap[i].name)
					free((char *)_nsmap[i].name);
			}
			if (_nsmap)
				free(_nsmap);
			_nsmap = NULL;
			_nsmapsize = 0;
			confmod = 0;
		}
	}
	if (!confmod) {
		if (stat(_PATH_NS_CONF, &statbuf) == -1)
			return (&dbt);
		_nsyyin = fopen(_PATH_NS_CONF, "r");
		if (_nsyyin == NULL)
			return (&dbt);
		_nsyyparse();
		(void)fclose(_nsyyin);
		qsort(_nsmap, _nsmapsize, sizeof(ns_dbt), _nscmp);
		confmod = statbuf.st_mtime;
	}
	ndbt = bsearch(&dbt, _nsmap, _nsmapsize, sizeof(ns_dbt), _nscmp);
	if (ndbt != NULL)
		return (ndbt);
	return (&dbt);
}


void
_nsdbtput(dbt)
	const ns_dbt *dbt;
{
	int	i;

	for (i = 0; i < _nsmapsize; i++) {
		if (_nscmp(dbt, &_nsmap[i]) == 0) {
					/* overwrite existing entry */
			if (_nsmap[i].srclist != NULL)
				free(_nsmap[i].srclist);
			memmove((void *)&_nsmap[i], (void *)dbt,
				sizeof(ns_dbt));
			return;
		}
	}

	if ((_nsmapsize % NSELEMSPERCHUNK) == 0) {
		_nsmap = (ns_dbt *)realloc(_nsmap,
		    (_nsmapsize + NSELEMSPERCHUNK) * sizeof(ns_dbt));
		if (_nsmap == NULL)
			err(1, "nsdispatch: memory allocation failure");
	}
	memmove((void *)&_nsmap[_nsmapsize++], (void *)dbt, sizeof(ns_dbt));
}


int
#if __STDC__
nsdispatch(void *retval, const ns_dtab disp_tab[], const char *database, ...)
#else
nsdispatch(retval, disp_tab, database, va_alist)
	void		*retval;
	const ns_dtab	 disp_tab[];
	const char	*database;
	va_dcl
#endif
{
	va_list		 ap;
	int		 i, curdisp, result;
	const ns_dbt	*dbt;

	dbt = _nsdbtget(database);
	result = 0;

#if _NS_DEBUG
	_nsdumpdbt(dbt);
	fprintf(stderr, "nsdispatch: %s\n", database);
#endif
	for (i = 0; i < dbt->srclistsize; i++) {
#if _NS_DEBUG
		fprintf(stderr, "    source=%s", dbt->srclist[i]->source);
#endif
		for (curdisp = 0; disp_tab[curdisp].src != NULL; curdisp++)
			if (strcasecmp(disp_tab[curdisp].src,
			    dbt->srclist[i].name) == 0)
				break;
		result = 0;
		if (disp_tab[curdisp].callback) {
#if __STDC__
			va_start(ap, database);
#else
			va_start(ap);
#endif
			result = disp_tab[curdisp].callback(retval,
			    disp_tab[curdisp].cb_data, ap);
			va_end(ap);
#if _NS_DEBUG
			fprintf(stderr, " result=%d (%d)", result,
			    (result & dbt->srclist[i].flags));
#endif
			if (result & dbt->srclist[i].flags) {
#if _NS_DEBUG
				fprintf(stderr, " MATCH!\n");
#endif
				break;
			}
		}
#if _NS_DEBUG
		fprintf(stderr, "\n");
#endif
	}
	return (result ? result : NS_NOTFOUND);
}