grp/fgetgrent_r.c

   1 /* Copyright (C) 1991, 1996, 1997, 1998 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Library General Public License as
   6    published by the Free Software Foundation; either version 2 of the
   7    License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Library General Public License for more details.
  13
  14    You should have received a copy of the GNU Library General Public
  15    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  16    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17    Boston, MA 02111-1307, USA.  */
  18
  19 #include <ctype.h>
  20 #include <grp.h>
  21 #include <stdio.h>
  22
  23 /* Define a line parsing function using the common code
  24    used in the nss_files module.  */
  25
  26 #define STRUCTURE       group
  27 #define ENTNAME         grent
  28 struct grent_data {};
  29
  30 #define TRAILING_LIST_MEMBER            gr_mem
  31 #define TRAILING_LIST_SEPARATOR_P(c)    ((c) == ',')
  32 #include "../nss/nss_files/files-parse.c"
  33 LINE_PARSER
  34 (,
  35  STRING_FIELD (result->gr_name, ISCOLON, 0);
  36  if (line[0] == '\0'
  37      && (result->gr_name[0] == '+' || result->gr_name[0] == '-'))
  38    {
  39      result->gr_passwd = NULL;
  40      result->gr_gid = 0;
  41    }
  42  else
  43    {
  44      STRING_FIELD (result->gr_passwd, ISCOLON, 0);
  45      if (result->gr_name[0] == '+' || result->gr_name[0] == '-')
  46        INT_FIELD_MAYBE_NULL (result->gr_gid, ISCOLON, 0, 10, , 0)
  47      else
  48        INT_FIELD (result->gr_gid, ISCOLON, 0, 10,)
  49    }
  50  )
  51
  52
  53 /* Read one entry from the given stream.  */
  54 int
  55 __fgetgrent_r (FILE *stream, struct group *resbuf, char *buffer, size_t buflen,
  56                struct group **result)
  57 {
  58   char *p;
  59   int parse_result;
  60
  61   do
  62     {
  63       buffer[buflen] = '\xff';
  64       p = fgets (buffer, buflen, stream);
  65       if (p == NULL && feof (stream))
  66         {
  67           *result = NULL;
  68           return errno;
  69         }
  70       if (p == NULL || buffer[buflen] != '\xff')
  71         {
  72           *result = NULL;
  73           return errno = ERANGE;
  74         }
  75
  76       /* Skip leading blanks.  */
  77       while (isspace (*p))
  78         ++p;
  79     } while (*p == '\0' || *p == '#'    /* Ignore empty and comment lines.  */
  80              /* Parse the line.  If it is invalid, loop to
  81                 get the next line of the file to parse.  */
  82              || ! (parse_result = parse_line (p, resbuf,
  83                                               (void *) buffer, buflen)));
  84
  85   if (parse_result == -1)
  86     {
  87       /* The parser ran out of space.  */
  88       *result = NULL;
  89       return errno;
  90     }
  91
  92   *result = resbuf;
  93   return 0;
  94 }
  95 weak_alias (__fgetgrent_r, fgetgrent_r)