gl/fstat.c

   1 /* fstat() replacement.
   2    Copyright (C) 2011-2012 Free Software Foundation, Inc.
   3
   4    This program is free software: you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation; either version 3 of the License, or
   7    (at your option) any later version.
   8
   9    This program 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
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  16
  17 /* If the user's config.h happens to include <sys/stat.h>, let it include only
  18    the system's <sys/stat.h> here, so that orig_fstat doesn't recurse to
  19    rpl_fstat.  */
  20 #define __need_system_sys_stat_h
  21 #include <config.h>
  22
  23 /* Get the original definition of fstat.  It might be defined as a macro.  */
  24 #include <sys/types.h>
  25 #include <sys/stat.h>
  26 #undef __need_system_sys_stat_h
  27
  28 static inline int
  29 orig_fstat (int fd, struct stat *buf)
  30 {
  31   return fstat (fd, buf);
  32 }
  33
  34 /* Specification.  */
  35 /* Write "sys/stat.h" here, not <sys/stat.h>, otherwise OSF/1 5.1 DTK cc
  36    eliminates this include because of the preliminary #include <sys/stat.h>
  37    above.  */
  38 #include "sys/stat.h"
  39
  40 #include <errno.h>
  41 #include <unistd.h>
  42
  43 #if HAVE_MSVC_INVALID_PARAMETER_HANDLER
  44 # include "msvc-inval.h"
  45 #endif
  46
  47 #if HAVE_MSVC_INVALID_PARAMETER_HANDLER
  48 static inline int
  49 fstat_nothrow (int fd, struct stat *buf)
  50 {
  51   int result;
  52
  53   TRY_MSVC_INVAL
  54     {
  55       result = orig_fstat (fd, buf);
  56     }
  57   CATCH_MSVC_INVAL
  58     {
  59       result = -1;
  60       errno = EBADF;
  61     }
  62   DONE_MSVC_INVAL;
  63
  64   return result;
  65 }
  66 #else
  67 # define fstat_nothrow orig_fstat
  68 #endif
  69
  70 int
  71 rpl_fstat (int fd, struct stat *buf)
  72 {
  73 #if REPLACE_FCHDIR && REPLACE_OPEN_DIRECTORY
  74   /* Handle the case when rpl_open() used a dummy file descriptor to work
  75      around an open() that can't normally visit directories.  */
  76   const char *name = _gl_directory_name (fd);
  77   if (name != NULL)
  78     return stat (name, buf);
  79 #endif
  80
  81   return fstat_nothrow (fd, buf);
  82 }