pwd/fgetpwent_r.c

   1 /* Copyright (C) 1991-2019 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 Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the 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    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, see
  16    <http://www.gnu.org/licenses/>.  */
  17
  18 #include <ctype.h>
  19 #include <errno.h>
  20 #include <stdio.h>
  21 #include <pwd.h>
  22
  23 #define flockfile(s) _IO_flockfile (s)
  24 #define funlockfile(s) _IO_funlockfile (s)
  25
  26 /* Define a line parsing function using the common code
  27    used in the nss_files module.  */
  28
  29 #define STRUCTURE       passwd
  30 #define ENTNAME         pwent
  31 struct pwent_data {};
  32
  33 #include <nss/nss_files/files-parse.c>
  34 LINE_PARSER
  35 (,
  36  STRING_FIELD (result->pw_name, ISCOLON, 0);
  37  if (line[0] == '\0'
  38      && (result->pw_name[0] == '+' || result->pw_name[0] == '-'))
  39    {
  40      /* This a special case.  We allow lines containing only a `+' sign
  41         since this is used for nss_compat.  All other services will
  42         reject this entry later.  Initialize all other fields now.  */
  43      result->pw_passwd = NULL;
  44      result->pw_uid = 0;
  45      result->pw_gid = 0;
  46      result->pw_gecos = NULL;
  47      result->pw_dir = NULL;
  48      result->pw_shell = NULL;
  49    }
  50  else
  51    {
  52      STRING_FIELD (result->pw_passwd, ISCOLON, 0);
  53      if (result->pw_name[0] == '+' || result->pw_name[0] == '-')
  54        {
  55          INT_FIELD_MAYBE_NULL (result->pw_uid, ISCOLON, 0, 10, , 0)
  56          INT_FIELD_MAYBE_NULL (result->pw_gid, ISCOLON, 0, 10, , 0)
  57        }
  58      else
  59        {
  60          INT_FIELD (result->pw_uid, ISCOLON, 0, 10,)
  61          INT_FIELD (result->pw_gid, ISCOLON, 0, 10,)
  62        }
  63      STRING_FIELD (result->pw_gecos, ISCOLON, 0);
  64      STRING_FIELD (result->pw_dir, ISCOLON, 0);
  65      result->pw_shell = line;
  66    }
  67  )
  68
  69
  70 /* Read one entry from the given stream.  */
  71 int
  72 __fgetpwent_r (FILE *stream, struct passwd *resbuf, char *buffer,
  73                size_t buflen, struct passwd **result)
  74 {
  75   char *p;
  76
  77   flockfile (stream);
  78   do
  79     {
  80       buffer[buflen - 1] = '\xff';
  81       p = fgets_unlocked (buffer, buflen, stream);
  82       if (p == NULL && feof_unlocked (stream))
  83         {
  84           funlockfile (stream);
  85           *result = NULL;
  86           __set_errno (ENOENT);
  87           return errno;
  88         }
  89       if (p == NULL || buffer[buflen - 1] != '\xff')
  90         {
  91           funlockfile (stream);
  92           *result = NULL;
  93           __set_errno (ERANGE);
  94           return errno;
  95         }
  96
  97       /* Skip leading blanks.  */
  98       while (isspace (*p))
  99         ++p;
 100     } while (*p == '\0' || *p == '#' /* Ignore empty and comment lines.  */
 101              /* Parse the line.  If it is invalid, loop to
 102                 get the next line of the file to parse.  */
 103              || ! parse_line (p, resbuf, (void *) buffer, buflen, &errno));
 104
 105   funlockfile (stream);
 106
 107   *result = resbuf;
 108   return 0;
 109 }
 110 weak_alias (__fgetpwent_r, fgetpwent_r)