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/*
* __getgrent.c - This file is part of the libc-8086/grp package for ELKS,
* Copyright (C) 1995, 1996 Nat Friedman <ndf@linux.mit.edu>.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the Free
* Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
*/
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <grp.h>
#include "config.h"
/*
* This is the core group-file read function. It behaves exactly like
* getgrent() except that it is passed a file descriptor. getgrent()
* is just a wrapper for this function.
*/
struct group *
__getgrent(int grp_fd)
{
#ifndef GR_SCALE_DYNAMIC
static char line_buff[GR_MAX_LINE_LEN];
static char * members[GR_MAX_MEMBERS];
#else
static char * line_buff = NULL;
static char ** members = NULL;
short line_index;
short buff_size;
#endif
static struct group group;
register char * ptr;
char * field_begin;
short member_num;
char * endptr;
int line_len;
/* We use the restart label to handle malformatted lines */
restart:
#ifdef GR_SCALE_DYNAMIC
line_index=0;
buff_size=256;
#endif
#ifndef GR_SCALE_DYNAMIC
/* Read the line into the static buffer */
if ((line_len=read(grp_fd, line_buff, GR_MAX_LINE_LEN))<=0)
return NULL;
field_begin=strchr(line_buff, '\n');
if (field_begin!=NULL)
lseek(grp_fd, (long) (1+field_begin-(line_buff+line_len)), SEEK_CUR);
else /* The line is too long - skip it :-\ */
{
do { if ((line_len=read(grp_fd, line_buff, GR_MAX_LINE_LEN))<=0)
return NULL;
} while (!(field_begin=strchr(line_buff, '\n')));
lseek(grp_fd, (long) ((field_begin-line_buff)-line_len+1), SEEK_CUR);
goto restart;
}
if (*line_buff=='#' || *line_buff==' ' || *line_buff=='\n' ||
*line_buff=='\t')
goto restart;
*field_begin='\0';
#else /* !GR_SCALE_DYNAMIC */
line_buff=realloc(line_buff, buff_size);
while (1)
{
if ((line_len=read(grp_fd, line_buff+line_index,
buff_size-line_index))<=0)
return NULL;
field_begin=strchr(line_buff, '\n');
if (field_begin!=NULL)
{
lseek(grp_fd, (long) (1+field_begin-(line_len+line_index+line_buff)),
SEEK_CUR);
*field_begin='\0';
if (*line_buff=='#' || *line_buff==' ' || *line_buff=='\n' ||
*line_buff=='\t')
goto restart;
break;
}
else /* Allocate some more space */
{
line_index=buff_size;
buff_size+=256;
line_buff=realloc(line_buff, buff_size);
}
}
#endif /* GR_SCALE_DYNAMIC */
/* Now parse the line */
group.gr_name=line_buff;
ptr=strchr(line_buff, ':');
if (ptr==NULL) goto restart;
*ptr++='\0';
group.gr_passwd=ptr;
ptr=strchr(ptr, ':');
if (ptr==NULL) goto restart;
*ptr++='\0';
field_begin=ptr;
ptr=strchr(ptr, ':');
if (ptr==NULL) goto restart;
*ptr++='\0';
group.gr_gid=(gid_t) strtoul(field_begin, &endptr, 10);
if (*endptr!='\0') goto restart;
member_num=0;
field_begin=ptr;
#ifndef GR_SCALE_DYNAMIC
while ((ptr=strchr(ptr, ','))!=NULL)
{
*ptr='\0';
ptr++;
members[member_num]=field_begin;
field_begin=ptr;
member_num++;
}
if (*field_begin=='\0')
members[member_num]=NULL;
else
{
members[member_num]=field_begin;
members[member_num+1]=NULL;
}
#else /* !GR_SCALE_DYNAMIC */
if (members!=NULL)
free (members);
members=(char **) malloc(1*sizeof(char *));
while ((ptr=strchr(ptr, ','))!=NULL)
{
*ptr='\0';
ptr++;
members[member_num]=field_begin;
field_begin=ptr;
member_num++;
members=(char **)realloc((void *)members, (member_num+1)*sizeof(char *));
}
if (*field_begin=='\0')
members[member_num]=NULL;
else
{
members[member_num]=field_begin;
members[member_num+1]=NULL;
}
#endif /* GR_SCALE_DYNAMIC */
group.gr_mem=members;
return &group;
}
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