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 <errno.h>
  21 #include <grp.h>
  22 #include <stdio.h>
  23
  24 #ifdef USE_IN_LIBIO
  25 # include <libio/iolibio.h>
  26 # define flockfile(s) _IO_flockfile (s)
  27 # define funlockfile(s) _IO_funlockfile (s)
  28 #endif
  29
  30 /* Define a line parsing function using the common code
  31    used in the nss_files module.  */
  32
  33 #define STRUCTURE       group
  34 #define ENTNAME         grent
  35 struct grent_data {};
  36
  37 #define TRAILING_LIST_MEMBER            gr_mem
  38 #define TRAILING_LIST_SEPARATOR_P(c)    ((c) == ',')
  39 #include <nss/nss_files/files-parse.c>
  40 LINE_PARSER
  41 (,
  42  STRING_FIELD (result->gr_name, ISCOLON, 0);
  43  if (line[0] == '\0'
  44      && (result->gr_name[0] == '+' || result->gr_name[0] == '-'))
  45    {
  46      result->gr_passwd = NULL;
  47      result->gr_gid = 0;
  48    }
  49  else
  50    {
  51      STRING_FIELD (result->gr_passwd, ISCOLON, 0);
  52      if (result->gr_name[0] == '+' || result->gr_name[0] == '-')
  53        INT_FIELD_MAYBE_NULL (result->gr_gid, ISCOLON, 0, 10, , 0)
  54      else
  55        INT_FIELD (result->gr_gid, ISCOLON, 0, 10,)
  56    }
  57  )
  58
  59
  60 /* Read one entry from the given stream.  */
  61 int
  62 __fgetgrent_r (FILE *stream, struct group *resbuf, char *buffer, size_t buflen,
  63                struct group **result)
  64 {
  65   char *p;
  66   int parse_result;
  67
  68   flockfile (stream);
  69   do
  70     {
  71       buffer[buflen - 1] = '\xff';
  72       p = fgets_unlocked (buffer, buflen, stream);
  73       if (p == NULL && feof_unlocked (stream))
  74         {
  75           funlockfile (stream);
  76           *result = NULL;
  77           return errno;
  78         }
  79       if (p == NULL || buffer[buflen - 1] != '\xff')
  80         {
  81           funlockfile (stream);
  82           *result = NULL;
  83           return errno = ERANGE;
  84         }
  85
  86       /* Skip leading blanks.  */
  87       while (isspace (*p))
  88         ++p;
  89     } while (*p == '\0' || *p == '#'    /* Ignore empty and comment lines.  */
  90              /* Parse the line.  If it is invalid, loop to
  91                 get the next line of the file to parse.  */
  92              || ! (parse_result = parse_line (p, resbuf,
  93                                               (void *) buffer, buflen,
  94                                               &errno)));
  95
  96   funlockfile (stream);
  97
  98   if (parse_result == -1)
  99     {
 100       /* The parser ran out of space.  */
 101       *result = NULL;
 102       return errno;
 103     }
 104
 105   *result = resbuf;
 106   return 0;
 107 }
 108 weak_alias (__fgetgrent_r, fgetgrent_r)