new module 'fstat'

[Bruno Haible]

fstat() also crashes on MSVC 9 for an invalid fd argument. This, together with
the need to use 'largefile' whenever there is an fstat() call of a file that
could be large than 2 GB, is enough justification for a new module 'fstat'.


2011-09-25  Bruno Haible  <address@hidden>

        New module 'fstat'.
        * lib/sys_stat.in.h (fstat): Declare only if GNULIB_FSTAT is set.
        * lib/fstat.c: New file, based on a piece of lib/fchdir.c.
        * lib/fchdir.c (rpl_fstat): Remove function.
        * m4/fstat.m4: New file.
        * m4/fchdir.m4 (gl_FUNC_FCHDIR): Don't set REPLACE_FSTAT.
        * m4/sys_stat_h.m4 (gl_HEADER_SYS_STAT_H): Test whether fstat is
        declared.
        (gl_SYS_STAT_H_DEFAULTS): Initialize GNULIB_FSTAT.
        * modules/sys_stat (Makefile.am): Substitute GNULIB_FSTAT.
        * modules/fstat: New file.
        * modules/sys_stat-tests (Depends-on): Remove fstat-tests.
        * tests/test-sys_stat-c++.cc (fstat): Check only if GNULIB_TEST_FSTAT
        is set.
        * doc/posix-functions/fstat.texi: Mention the new module and the
        problem on MSVC.
        * NEWS: Mention the change.
        * modules/acl (Depends-on): Add fstat.
        * modules/chdir-safer (Depends-on): Likewise.
        * modules/chown (Depends-on): Likewise.
        * modules/copy-file (Depends-on): Likewise.
        * modules/fchdir (Depends-on): Likewise.
        * modules/fdopendir (Depends-on): Likewise.
        * modules/fopen (Depends-on): Likewise.
        * modules/fts (Depends-on): Likewise.
        * modules/getcwd (Depends-on): Likewise.
        * modules/isapipe (Depends-on): Likewise.
        * modules/linkat (Depends-on): Likewise.
        * modules/lseek (Depends-on): Likewise.
        * modules/mkdir-p (Depends-on): Likewise.
        * modules/open (Depends-on): Likewise.
        * modules/openat (Depends-on): Likewise.
        * modules/read-file (Depends-on): Likewise.
        * modules/renameat (Depends-on): Likewise.
        * modules/utimens (Depends-on): Likewise.

================================= lib/fstat.c =================================
/* fstat() replacement.
   Copyright (C) 2011 Free Software Foundation, Inc.

   This program is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

/* If the user's config.h happens to include <sys/stat.h>, let it include only
   the system's <sys/stat.h> here, so that orig_fstat doesn't recurse to
   rpl_fstat.  */
#define __need_system_sys_stat_h
#include <config.h>

/* Get the original definition of fstat.  It might be defined as a macro.  */
#include <sys/types.h>
#include <sys/stat.h>
#undef __need_system_sys_stat_h

static inline int
orig_fstat (int fd, struct stat *buf)
{
  return fstat (fd, buf);
}

/* Specification.  */
/* Write "sys/stat.h" here, not <sys/stat.h>, otherwise OSF/1 5.1 DTK cc
   eliminates this include because of the preliminary #include <sys/stat.h>
   above.  */
#include "sys/stat.h"

#include <errno.h>
#include <unistd.h>

#if HAVE_MSVC_INVALID_PARAMETER_HANDLER
# include "msvc-inval.h"
#endif

#if HAVE_MSVC_INVALID_PARAMETER_HANDLER
static inline int
fstat_nothrow (int fd, struct stat *buf)
{
  int result;

  TRY_MSVC_INVAL
    {
      result = orig_fstat (fd, buf);
    }
  CATCH_MSVC_INVAL
    {
      result = -1;
      errno = EBADF;
    }
  DONE_MSVC_INVAL;

  return result;
}
#else
# define fstat_nothrow orig_fstat
#endif

int
rpl_fstat (int fd, struct stat *buf)
{
#if REPLACE_FCHDIR && REPLACE_OPEN_DIRECTORY
  /* Handle the case when rpl_open() used a dummy file descriptor to work
     around an open() that can't normally visit directories.  */
  const char *name = _gl_directory_name (fd);
  if (name != NULL)
    return stat (name, buf);
#endif

  return fstat_nothrow (fd, buf);
}
================================= m4/fstat.m4 =================================
# fstat.m4 serial 1
dnl Copyright (C) 2011 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
dnl with or without modifications, as long as this notice is preserved.

AC_DEFUN([gl_FUNC_FSTAT],
[
  AC_REQUIRE([gl_SYS_STAT_H_DEFAULTS])
  AC_REQUIRE([gl_MSVC_INVAL])
  if test $HAVE_MSVC_INVALID_PARAMETER_HANDLER = 1; then
    REPLACE_FSTAT=1
  fi
  dnl Replace fstat() for supporting the gnulib-defined open() on directories.
  m4_ifdef([gl_FUNC_FCHDIR], [
    gl_TEST_FCHDIR
    if test $HAVE_FCHDIR = 0 \
       && test "$gl_cv_func_open_directory_works" != yes; then
      REPLACE_FSTAT=1
    fi
  ])
])

# Prerequisites of lib/fstat.c.
AC_DEFUN([gl_PREREQ_FSTAT],
[
  AC_REQUIRE([AC_C_INLINE])
])
================================ modules/fstat ================================
Description:
fstat() function: query file information

Files:
lib/fstat.c
m4/fstat.m4

Depends-on:
sys_stat
largefile
unistd          [test $REPLACE_STAT = 1]
msvc-inval      [test $REPLACE_STAT = 1]

configure.ac:
gl_FUNC_FSTAT
if test $REPLACE_FSTAT = 1; then
  AC_LIBOBJ([fstat])
  gl_PREREQ_FSTAT
fi
gl_SYS_STAT_MODULE_INDICATOR([fstat])

Makefile.am:

Include:
<sys/stat.h>

License:
LGPLv2+

Maintainer:
Bruno Haible
===============================================================================
--- NEWS.orig   Sun Sep 25 13:41:48 2011
+++ NEWS        Sun Sep 25 12:32:21 2011
@@ -12,6 +12,10 @@
 
 Date        Modules         Changes
 
+2011-09-25  sys_stat        This module no longer provides the fstat()
+                            function. If you need this function, you now need
+                            to request the 'fstat' module.
+
 2011-09-23  signal          This module is renamed to 'signal-h'.
 
 2011-09-22  select          The link requirements of this module are changed
--- doc/posix-functions/fstat.texi.orig Sun Sep 25 13:41:48 2011
+++ doc/posix-functions/fstat.texi      Sun Sep 25 12:28:40 2011
@@ -4,18 +4,21 @@
 
 POSIX specification:@* 
@url{http://www.opengroup.org/onlinepubs/9699919799/functions/fstat.html}
 
-Gnulib module: ---
+Gnulib module: fstat
 
 Portability problems fixed by Gnulib:
 @itemize
address@hidden itemize
-
-Portability problems not fixed by Gnulib:
address@hidden
address@hidden
+This function crashes when invoked with invalid arguments on some platforms:
+MSVC 9.
 @item
 On platforms where @code{off_t} is a 32-bit type, @code{fstat} may not 
correctly
 report the size of files or block devices larger than 2 GB.  The fix is to
 use the @code{AC_SYS_LARGEFILE} macro.
address@hidden itemize
+
+Portability problems not fixed by Gnulib:
address@hidden
 @item
 On Cygwin, @code{fstat} applied to the file descriptors 0 and 1, returns
 different @code{st_ino} values, even if standard input and standard output
--- lib/fchdir.c.orig   Sun Sep 25 13:41:48 2011
+++ lib/fchdir.c        Sun Sep 25 12:45:53 2011
@@ -197,20 +197,6 @@
   return NULL;
 }
 
-#if REPLACE_OPEN_DIRECTORY
-/* Return stat information about FD in STATBUF.  Needed when
-   rpl_open() used a dummy file to work around an open() that can't
-   normally visit directories.  */
-# undef fstat
-int
-rpl_fstat (int fd, struct stat *statbuf)
-{
-  if (0 <= fd && fd < dirs_allocated && dirs[fd].name != NULL)
-    return stat (dirs[fd].name, statbuf);
-  return fstat (fd, statbuf);
-}
-#endif
-
 
 /* Implement fchdir() in terms of chdir().  */
 
--- lib/sys_stat.in.h.orig      Sun Sep 25 13:41:48 2011
+++ lib/sys_stat.in.h   Sun Sep 25 12:25:13 2011
@@ -319,16 +319,25 @@
 #endif
 
 
-#if @REPLACE_FSTAT@
-# if !(defined __cplusplus && defined GNULIB_NAMESPACE)
-#  define fstat rpl_fstat
-# endif
+#if @GNULIB_FSTAT@
+# if @REPLACE_FSTAT@
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   undef fstat
+#   define fstat rpl_fstat
+#  endif
 _GL_FUNCDECL_RPL (fstat, int, (int fd, struct stat *buf) _GL_ARG_NONNULL 
((2)));
 _GL_CXXALIAS_RPL (fstat, int, (int fd, struct stat *buf));
-#else
+# else
 _GL_CXXALIAS_SYS (fstat, int, (int fd, struct stat *buf));
-#endif
+# endif
 _GL_CXXALIASWARN (fstat);
+#elif defined GNULIB_POSIXCHECK
+# undef fstat
+# if HAVE_RAW_DECL_FSTAT
+_GL_WARN_ON_USE (fstat, "fstat has portability problems - "
+                 "use gnulib module fstat for portability");
+# endif
+#endif
 
 
 #if @GNULIB_FSTATAT@
--- m4/fchdir.m4.orig   Sun Sep 25 13:41:48 2011
+++ m4/fchdir.m4        Sun Sep 25 13:34:10 2011
@@ -1,4 +1,4 @@
-# fchdir.m4 serial 19
+# fchdir.m4 serial 20
 dnl Copyright (C) 2006-2011 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -8,7 +8,6 @@
 [
   AC_REQUIRE([gl_UNISTD_H_DEFAULTS])
   AC_REQUIRE([gl_DIRENT_H_DEFAULTS])
-  AC_REQUIRE([gl_SYS_STAT_H_DEFAULTS])
 
   AC_CHECK_DECLS_ONCE([fchdir])
   if test $ac_cv_have_decl_fchdir = no; then
@@ -34,7 +33,6 @@
     if test "$gl_cv_func_open_directory_works" != yes; then
       AC_DEFINE([REPLACE_OPEN_DIRECTORY], [1], [Define to 1 if open() should
 work around the inability to open a directory.])
-      REPLACE_FSTAT=1
     fi
   fi
 ])
--- m4/sys_stat_h.m4.orig       Sun Sep 25 13:41:48 2011
+++ m4/sys_stat_h.m4    Sun Sep 25 12:25:48 2011
@@ -1,4 +1,4 @@
-# sys_stat_h.m4 serial 25   -*- Autoconf -*-
+# sys_stat_h.m4 serial 26   -*- Autoconf -*-
 dnl Copyright (C) 2006-2011 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -33,7 +33,7 @@
   dnl Check for declarations of anything we want to poison if the
   dnl corresponding gnulib module is not in use.
   gl_WARN_ON_USE_PREPARE([[#include <sys/stat.h>
-    ]], [fchmodat fstatat futimens lchmod lstat mkdirat mkfifo mkfifoat
+    ]], [fchmodat fstat fstatat futimens lchmod lstat mkdirat mkfifo mkfifoat
     mknod mknodat stat utimensat])
 ]) # gl_HEADER_SYS_STAT_H
 
@@ -50,6 +50,7 @@
 [
   AC_REQUIRE([gl_UNISTD_H_DEFAULTS]) dnl for REPLACE_FCHDIR
   GNULIB_FCHMODAT=0;    AC_SUBST([GNULIB_FCHMODAT])
+  GNULIB_FSTAT=0;       AC_SUBST([GNULIB_FSTAT])
   GNULIB_FSTATAT=0;     AC_SUBST([GNULIB_FSTATAT])
   GNULIB_FUTIMENS=0;    AC_SUBST([GNULIB_FUTIMENS])
   GNULIB_LCHMOD=0;      AC_SUBST([GNULIB_LCHMOD])
--- modules/acl.orig    Sun Sep 25 13:41:48 2011
+++ modules/acl Sun Sep 25 12:52:10 2011
@@ -12,6 +12,7 @@
 
 Depends-on:
 error
+fstat
 gettext-h
 quote
 sys_stat
--- modules/chdir-safer.orig    Sun Sep 25 13:41:48 2011
+++ modules/chdir-safer Sun Sep 25 12:51:35 2011
@@ -10,6 +10,7 @@
 errno
 fchdir
 fcntl-h
+fstat
 open
 same-inode
 stdbool
--- modules/chown.orig  Sun Sep 25 13:41:48 2011
+++ modules/chown       Sun Sep 25 12:51:53 2011
@@ -8,6 +8,7 @@
 
 Depends-on:
 unistd
+fstat           [test $HAVE_CHOWN = 0 || test $REPLACE_CHOWN = 1]
 open            [test $HAVE_CHOWN = 0 || test $REPLACE_CHOWN = 1]
 stat            [test $HAVE_CHOWN = 0 || test $REPLACE_CHOWN = 1]
 stdbool         [test $HAVE_CHOWN = 0 || test $REPLACE_CHOWN = 1]
--- modules/copy-file.orig      Sun Sep 25 13:41:48 2011
+++ modules/copy-file   Sun Sep 25 12:52:23 2011
@@ -10,6 +10,7 @@
 acl
 binary-io
 error
+fstat
 full-write
 gettext-h
 open
--- modules/fchdir.orig Sun Sep 25 13:41:48 2011
+++ modules/fchdir      Sun Sep 25 12:53:31 2011
@@ -16,6 +16,7 @@
 fcntl            [test $HAVE_FCHDIR = 0]
 fcntl-h          [test $HAVE_FCHDIR = 0]
 filenamecat-lgpl [test $HAVE_FCHDIR = 0]
+fstat            [test $HAVE_FCHDIR = 0]
 getcwd-lgpl      [test $HAVE_FCHDIR = 0]
 malloc-posix     [test $HAVE_FCHDIR = 0]
 open             [test $HAVE_FCHDIR = 0]
--- modules/fdopendir.orig      Sun Sep 25 13:41:48 2011
+++ modules/fdopendir   Sun Sep 25 12:53:53 2011
@@ -13,6 +13,7 @@
 dup             [test $HAVE_FDOPENDIR = 0]
 errno           [test $HAVE_FDOPENDIR = 0]
 fchdir          [test $HAVE_FDOPENDIR = 0]
+fstat           [test $HAVE_FDOPENDIR = 0]
 openat-die      [test $HAVE_FDOPENDIR = 0]
 opendir         [test $HAVE_FDOPENDIR = 0]
 save-cwd        [test $HAVE_FDOPENDIR = 0]
--- modules/fopen.orig  Sun Sep 25 13:41:48 2011
+++ modules/fopen       Sun Sep 25 12:54:11 2011
@@ -9,6 +9,7 @@
 stdio
 largefile
 unistd          [test $REPLACE_FOPEN = 1]
+fstat           [test $REPLACE_FOPEN = 1]
 
 configure.ac:
 gl_FUNC_FOPEN
--- modules/fts.orig    Sun Sep 25 13:41:48 2011
+++ modules/fts Sun Sep 25 12:54:27 2011
@@ -18,6 +18,7 @@
 fchdir
 fcntl-h
 fcntl-safer
+fstat
 hash
 i-ring
 lstat
--- modules/getcwd.orig Sun Sep 25 13:41:48 2011
+++ modules/getcwd      Sun Sep 25 12:55:26 2011
@@ -16,6 +16,7 @@
 d-ino           [test $REPLACE_GETCWD = 1]
 memmove         [test $REPLACE_GETCWD = 1]
 openat          [test $REPLACE_GETCWD = 1]
+fstat           [test $REPLACE_GETCWD = 1]
 opendir         [test $REPLACE_GETCWD = 1]
 closedir        [test $REPLACE_GETCWD = 1]
 stdbool         [test $REPLACE_GETCWD = 1]
--- modules/isapipe.orig        Sun Sep 25 13:41:48 2011
+++ modules/isapipe     Sun Sep 25 12:55:52 2011
@@ -11,6 +11,7 @@
 sys_stat        [test $HAVE_ISAPIPE = 0]
 unistd          [test $HAVE_ISAPIPE = 0]
 msvc-nothrow    [test $HAVE_ISAPIPE = 0]
+fstat           [test $HAVE_ISAPIPE = 0]
 
 configure.ac:
 gl_ISAPIPE
--- modules/linkat.orig Sun Sep 25 13:41:48 2011
+++ modules/linkat      Sun Sep 25 12:50:55 2011
@@ -16,6 +16,7 @@
 errno            [test $HAVE_LINKAT = 0 || test $REPLACE_LINKAT = 1]
 fcntl-h          [test $HAVE_LINKAT = 0 || test $REPLACE_LINKAT = 1]
 filenamecat-lgpl [test $HAVE_LINKAT = 0 || test $REPLACE_LINKAT = 1]
+fstat            [test $HAVE_LINKAT = 0 || test $REPLACE_LINKAT = 1]
 getcwd-lgpl      [test $HAVE_LINKAT = 0 || test $REPLACE_LINKAT = 1]
 openat           [test $HAVE_LINKAT = 0 || test $REPLACE_LINKAT = 1]
 link             [test $HAVE_LINKAT = 0 || test $REPLACE_LINKAT = 1]
--- modules/lseek.orig  Sun Sep 25 13:41:48 2011
+++ modules/lseek       Sun Sep 25 12:56:08 2011
@@ -9,6 +9,7 @@
 unistd
 largefile
 msvc-nothrow    [test $REPLACE_LSEEK = 1]
+fstat           [test $REPLACE_LSEEK = 1]
 
 configure.ac:
 gl_FUNC_LSEEK
--- modules/mkdir-p.orig        Sun Sep 25 13:41:48 2011
+++ modules/mkdir-p     Sun Sep 25 12:52:56 2011
@@ -11,6 +11,7 @@
 Depends-on:
 error
 fcntl-h
+fstat
 gettext-h
 lchmod
 lchown
--- modules/open.orig   Sun Sep 25 13:41:48 2011
+++ modules/open        Sun Sep 25 12:56:25 2011
@@ -9,6 +9,7 @@
 Depends-on:
 fcntl-h
 largefile
+fstat           [test $REPLACE_OPEN = 1]
 stat            [test $REPLACE_OPEN = 1]
 
 configure.ac:
--- modules/openat.orig Sun Sep 25 13:41:48 2011
+++ modules/openat      Sun Sep 25 12:57:04 2011
@@ -22,6 +22,7 @@
 fchdir
 fcntl-h
 fdopendir
+fstat
 gettext-h
 intprops
 largefile
--- modules/read-file.orig      Sun Sep 25 13:41:48 2011
+++ modules/read-file   Sun Sep 25 12:57:23 2011
@@ -7,6 +7,7 @@
 m4/read-file.m4
 
 Depends-on:
+fstat
 ftello
 malloc-posix
 realloc-posix
--- modules/renameat.orig       Sun Sep 25 13:41:48 2011
+++ modules/renameat    Sun Sep 25 12:51:12 2011
@@ -12,6 +12,7 @@
 fcntl-h
 dosname          [test $HAVE_RENAMEAT = 0 || test $REPLACE_RENAMEAT = 1]
 filenamecat-lgpl [test $HAVE_RENAMEAT = 0 || test $REPLACE_RENAMEAT = 1]
+fstat            [test $HAVE_RENAMEAT = 0 || test $REPLACE_RENAMEAT = 1]
 getcwd-lgpl      [test $HAVE_RENAMEAT = 0 || test $REPLACE_RENAMEAT = 1]
 openat           [test $HAVE_RENAMEAT = 0 || test $REPLACE_RENAMEAT = 1]
 rename           [test $HAVE_RENAMEAT = 0 || test $REPLACE_RENAMEAT = 1]
--- modules/sys_stat.orig       Sun Sep 25 13:41:48 2011
+++ modules/sys_stat    Sun Sep 25 12:26:11 2011
@@ -32,6 +32,7 @@
              -e 's|@''PRAGMA_COLUMNS''@|@PRAGMA_COLUMNS@|g' \
              -e 's|@''NEXT_SYS_STAT_H''@|$(NEXT_SYS_STAT_H)|g' \
              -e 's/@''GNULIB_FCHMODAT''@/$(GNULIB_FCHMODAT)/g' \
+             -e 's/@''GNULIB_FSTAT''@/$(GNULIB_FSTAT)/g' \
              -e 's/@''GNULIB_FSTATAT''@/$(GNULIB_FSTATAT)/g' \
              -e 's/@''GNULIB_FUTIMENS''@/$(GNULIB_FUTIMENS)/g' \
              -e 's/@''GNULIB_LCHMOD''@/$(GNULIB_LCHMOD)/g' \
--- modules/sys_stat-tests.orig Sun Sep 25 13:41:48 2011
+++ modules/sys_stat-tests      Sun Sep 25 13:30:54 2011
@@ -4,7 +4,6 @@
 Depends-on:
 verify
 sys_stat-c++-tests
-fstat-tests
 
 configure.ac:
 
--- modules/utimens.orig        Sun Sep 25 13:41:48 2011
+++ modules/utimens     Sun Sep 25 12:57:58 2011
@@ -10,6 +10,7 @@
 
 Depends-on:
 errno
+fstat
 lstat
 gettime
 stat-time
--- tests/test-sys_stat-c++.cc.orig     Sun Sep 25 13:41:48 2011
+++ tests/test-sys_stat-c++.cc  Sun Sep 25 12:26:35 2011
@@ -29,7 +29,9 @@
                  (int, char const *, mode_t, int));
 #endif
 
+#if GNULIB_TEST_FSTAT
 SIGNATURE_CHECK (GNULIB_NAMESPACE::fstat, int, (int, struct stat *));
+#endif
 
 #if GNULIB_TEST_FSTATAT
 SIGNATURE_CHECK (GNULIB_NAMESPACE::fstatat, int,

-- 
In memoriam Safia Ahmed-jan <http://en.wikipedia.org/wiki/Safia_Ahmed-jan>