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/* vi: set sw=4 ts=4: */
/*
* __getgrent.c - This file is part of the libc-8086/grp package for ELKS,
* Copyright (C) 1995, 1996 Nat Friedman <ndf@linux.mit.edu>.
* Copyright (C) 2001-2003 Erik Andersen <andersee@debian.org>
*
* 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 <features.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <errno.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.
*/
int __getgrent_r (struct group *__restrict group,
char *__restrict line_buff, size_t buflen, int grp_fd)
{
char *endptr, *field_begin, **members;
int i, line_len, member_num = 0;
if (buflen<GRP_BUFFER_SIZE) {
return ERANGE;
}
/* We use the restart label to handle malformatted lines */
restart:
/* Read the group line into the buffer for processing */
if ((line_len = read(grp_fd, line_buff, buflen)) <= 0) {
return EIO;
}
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, buflen)) <= 0) {
return EIO;
}
} 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';
/* We've read the line; now parse it. */
field_begin = line_buff;
for (i = 0; i < 3; i++) {
switch (i) {
case 0:
group->gr_name = field_begin;
break;
case 1:
group->gr_passwd = field_begin;
break;
case 2:
group->gr_gid = (__gid_t) strtoul(field_begin, &endptr, 10);
if (*endptr != ':')
goto restart;
break;
}
if (i < 3) {
field_begin = strchr(field_begin, ':');
if (field_begin == NULL)
break;
*field_begin++ = '\0';
}
}
members = (char **) malloc(sizeof(char *));
if (members==NULL) {
return ENOMEM;
}
while(field_begin && strlen(field_begin)) {
members[member_num++] = field_begin;
members = (char **) realloc(members, (member_num + 1) * sizeof(char *));
if (members==NULL) {
return ENOMEM;
}
endptr = strchr(field_begin, ',');
if (endptr == NULL) {
/* Final entry */
break;
}
*field_begin++ = '\0';
}
members[member_num] = NULL;
group->gr_mem = members;
return 0;
}
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