text: /*
   * __tlg_getpwent.c - This file is part of the libc-8086/pwd 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 <stdlib.h>
  #include <unistd.h>
  #include <string.h>
  #include <fcntl.h>
  #include "pwd.h"
  
  #define PWD_BUFFER_SIZE 256
  
  /* This isn't as flash as my previous version -- it doesn't dynamically
    scale down the gecos on too-long lines, but it also makes fewer syscalls,
    so it's probably nicer.  Write me if you want the old version.  Maybe I
    should include it as a build-time option... ?
    -Nat <ndf@linux.mit.edu> */
  
  struct passwd *__tlg_getpwent(int pwd_fd)
  {
  	static char line_buff[PWD_BUFFER_SIZE];
  	static struct passwd passwd;
  	char *field_begin;
  	char *endptr;
  	char *gid_ptr=NULL;
  	char *uid_ptr=NULL;
  	int line_len;
  	int i;
  
  	/* We use the restart label to handle malformatted lines */
    restart:
  	/* Read the passwd line into the static buffer using a minimal of
  	   syscalls. */
  	if ((line_len = read(pwd_fd, line_buff, PWD_BUFFER_SIZE)) <= 0)
  		return NULL;
  	field_begin = strchr(line_buff, '\n');
  	if (field_begin != NULL)
  		lseek(pwd_fd, (long) (1 + field_begin - (line_buff + line_len)),
  			  SEEK_CUR);
  	else {						/* The line is too long - skip it. :-\ */
  
  		do {
  			if ((line_len = read(pwd_fd, line_buff, PWD_BUFFER_SIZE)) <= 0)
  				return NULL;
  		} while (!(field_begin = strchr(line_buff, '\n')));
  		lseek(pwd_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 < 7; i++) {
  		switch (i) {
  		case 0:
  			passwd.pw_name = field_begin;
  			break;
  		case 1:
  			passwd.pw_passwd = field_begin;
  			break;
  		case 2:
  			uid_ptr = field_begin;
  			break;
  		case 3:
  			gid_ptr = field_begin;
  			break;
  		case 4:
  			passwd.pw_gecos = field_begin;
  			break;
  		case 5:
  			passwd.pw_dir = field_begin;
  			break;
  		case 6:
  			passwd.pw_shell = field_begin;
  			break;
  		}
  		if (i < 6) {
  			field_begin = strchr(field_begin, ':');
  			if (field_begin == NULL)
  				goto restart;
  			*field_begin++ = '\0';
  		}
  	}
  	passwd.pw_gid = (gid_t) strtoul(gid_ptr, &endptr, 10);
  	if (*endptr != '\0')
  		goto restart;
  
  	passwd.pw_uid = (uid_t) strtoul(uid_ptr, &endptr, 10);
  	if (*endptr != '\0')
  		goto restart;
  
  	return &passwd;
  }
  