nss/nss_fgetent_r.c

   1 /* Generic implementation of fget*ent_r.
   2    Copyright (C) 2020-2023 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19 #include <errno.h>
  20 #include <nss_files.h>
  21 #include <stdbool.h>
  22
  23 int
  24 __nss_fgetent_r (FILE *fp, void *result, char *buffer, size_t buffer_length,
  25                  nss_files_parse_line parser)
  26 {
  27   int ret;
  28
  29   _IO_flockfile (fp);
  30
  31   while (true)
  32     {
  33       off64_t original_offset;
  34       ret = __nss_readline (fp, buffer, buffer_length, &original_offset);
  35       if (ret == 0)
  36         {
  37           /* Parse the line into *RESULT.  */
  38           ret = parser (buffer, result,
  39                         (struct parser_data *) buffer, buffer_length, &errno);
  40
  41           /* Translate the result code from the parser into an errno
  42              value.  Also seeks back to the start of the line if
  43              necessary.  */
  44           ret = __nss_parse_line_result (fp, original_offset, ret);
  45
  46           if (ret == EINVAL)
  47             /* Skip over malformed lines.  */
  48             continue;
  49         }
  50       break;
  51     }
  52
  53   _IO_funlockfile (fp);
  54
  55   return ret;
  56 }