NetBSD/lib/libc/gen/getusershell.c

141 lines
3.8 KiB
C

/*
* Copyright (c) 1985 Regents of the University of California.
* All rights reserved.
*
* 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 University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University 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 REGENTS 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 REGENTS 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.
*/
#if defined(LIBC_SCCS) && !defined(lint)
/*static char *sccsid = "from: @(#)getusershell.c 5.7 (Berkeley) 2/23/91";*/
static char *rcsid = "$Id: getusershell.c,v 1.4 1993/08/26 00:44:45 jtc Exp $";
#endif /* LIBC_SCCS and not lint */
#include <sys/param.h>
#include <sys/file.h>
#include <sys/stat.h>
#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#define SHELLS "/etc/shells"
/*
* Do not add local shells here. They should be added in /etc/shells
*/
static char *okshells[] =
{ "/bin/sh", "/bin/csh", 0 };
static char **shells, *strings;
static char **curshell = NULL;
static char **initshells();
/*
* Get a list of shells from SHELLS, if it exists.
*/
char *
getusershell()
{
char *ret;
if (curshell == NULL)
curshell = initshells();
ret = *curshell;
if (ret != NULL)
curshell++;
return (ret);
}
void
endusershell()
{
if (shells != NULL)
free((char *)shells);
shells = NULL;
if (strings != NULL)
free(strings);
strings = NULL;
curshell = NULL;
}
void
setusershell()
{
curshell = initshells();
}
static char **
initshells()
{
register char **sp, *cp;
register FILE *fp;
struct stat statb;
if (shells != NULL)
free((char *)shells);
shells = NULL;
if (strings != NULL)
free(strings);
strings = NULL;
if ((fp = fopen(SHELLS, "r")) == (FILE *)0)
return(okshells);
if (fstat(fileno(fp), &statb) == -1) {
(void)fclose(fp);
return(okshells);
}
if ((strings = malloc((unsigned)statb.st_size)) == NULL) {
(void)fclose(fp);
return(okshells);
}
shells = (char **)calloc((unsigned)statb.st_size / 3, sizeof (char *));
if (shells == NULL) {
(void)fclose(fp);
free(strings);
strings = NULL;
return(okshells);
}
sp = shells;
cp = strings;
while (fgets(cp, MAXPATHLEN + 1, fp) != NULL) {
while (*cp != '#' && *cp != '/' && *cp != '\0')
cp++;
if (*cp == '#' || *cp == '\0')
continue;
*sp++ = cp;
while (!isspace(*cp) && *cp != '#' && *cp != '\0')
cp++;
*cp++ = '\0';
}
*sp = (char *)0;
(void)fclose(fp);
return (shells);
}