new module 'chdir'

[Bruno Haible]

Also the chdir() function is not declared in <unistd.h>, but in <direct.h>,
on MSVC 9. This fixes the problem.

2011-09-23  Bruno Haible  <address@hidden>

        New module 'chdir'.
        * modules/chdir: New file.
        * lib/unistd.in.h: Include <io.h>, <direct.h> also for chdir.
        (chdir): New declaration.
        * m4/unistd_h.m4 (gl_UNISTD_H): Test whether chdir is declared.
        (gl_UNISTD_H_DEFAULTS): Initialize GNULIB_CHDIR.
        * modules/unistd (Makefile.am): Substitute GNULIB_CHDIR.
        * tests/test-unistd-c++.cc: Check signature of chdir.
        * doc/posix-functions/chdir.texi: Mention problem on native Windows.
        * modules/chdir-long (Depends-on): Add chdir.
        * modules/fchdir (Depends-on): Likewise.
        * modules/rename (Depends-on): Likewise.
        * modules/savewd (Depends-on): Likewise.

================================ modules/chdir ================================
Description:
chdir() function: switch to another current directory

Files:

Depends-on:
unistd

configure.ac:
gl_UNISTD_MODULE_INDICATOR([chdir])

Makefile.am:

Include:
<unistd.h>

License:
LGPLv2+

Maintainer:
Bruno Haible
===============================================================================
--- doc/posix-functions/chdir.texi.orig Fri Sep 23 12:28:28 2011
+++ doc/posix-functions/chdir.texi      Fri Sep 23 12:03:02 2011
@@ -8,6 +8,10 @@
 
 Portability problems fixed by Gnulib:
 @itemize
address@hidden
+This function is declared in different header files (namely, @code{<io.h>} or
address@hidden<direct.h>}) on some platforms:
+mingw, MSVC 9.
 @end itemize
 
 Portability problems not fixed by Gnulib:
--- lib/unistd.in.h.orig        Fri Sep 23 12:28:28 2011
+++ lib/unistd.in.h     Fri Sep 23 12:15:07 2011
@@ -83,9 +83,10 @@
 # include <stdlib.h>
 #endif
 
-/* Native Windows platforms declare getcwd, rmdir in
+/* Native Windows platforms declare chdir, getcwd, rmdir in
    <io.h> and/or <direct.h>, not in <unistd.h>.  */
-#if ((@GNULIB_GETCWD@ || @GNULIB_RMDIR@ || defined GNULIB_POSIXCHECK) \
+#if ((@GNULIB_CHDIR@ || @GNULIB_GETCWD@ || @GNULIB_RMDIR@ \
+      || defined GNULIB_POSIXCHECK) \
      && ((defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__))
 # include <io.h>     /* mingw32, mingw64 */
 # include <direct.h> /* mingw64, MSVC 9 */
@@ -232,6 +233,18 @@ _GL_WARN_ON_USE (access, "the access function is a 
security risk - "
 #endif
 
 
+#if @GNULIB_CHDIR@
+_GL_CXXALIAS_SYS (chdir, int, (const char *file) _GL_ARG_NONNULL ((1)));
+_GL_CXXALIASWARN (chdir);
+#elif defined GNULIB_POSIXCHECK
+# undef chdir
+# if HAVE_RAW_DECL_CHDIR
+_GL_WARN_ON_USE (chown, "chdir is not always in <unistd.h> - "
+                 "use gnulib module chdir for portability");
+# endif
+#endif
+
+
 #if @GNULIB_CHOWN@
 /* Change the owner of FILE to UID (if UID is not -1) and the group of FILE
    to GID (if GID is not -1).  Follow symbolic links.
--- m4/unistd_h.m4.orig Fri Sep 23 12:28:28 2011
+++ m4/unistd_h.m4      Fri Sep 23 12:15:49 2011
@@ -1,4 +1,4 @@
-# unistd_h.m4 serial 59
+# unistd_h.m4 serial 60
 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,
@@ -39,7 +39,7 @@
 #  include <io.h>
 # endif
 #endif
-    ]], [chown dup2 dup3 environ euidaccess faccessat fchdir fchownat
+    ]], [chdir chown dup2 dup3 environ euidaccess faccessat fchdir fchownat
     fdatasync fsync ftruncate getcwd getdomainname getdtablesize getgroups
     gethostname getlogin getlogin_r getpagesize getusershell setusershell
     endusershell group_member lchown link linkat lseek pipe pipe2 pread pwrite
@@ -58,6 +58,7 @@
 
 AC_DEFUN([gl_UNISTD_H_DEFAULTS],
 [
+  GNULIB_CHDIR=0;                AC_SUBST([GNULIB_CHDIR])
   GNULIB_CHOWN=0;                AC_SUBST([GNULIB_CHOWN])
   GNULIB_CLOSE=0;                AC_SUBST([GNULIB_CLOSE])
   GNULIB_DUP2=0;                 AC_SUBST([GNULIB_DUP2])
--- modules/chdir-long.orig     Fri Sep 23 12:28:28 2011
+++ modules/chdir-long  Fri Sep 23 12:20:02 2011
@@ -10,6 +10,7 @@
 Depends-on:
 unistd
 pathmax
+chdir
 atexit          [test $gl_cv_have_arbitrary_file_name_length_limit = yes]
 fchdir          [test $gl_cv_have_arbitrary_file_name_length_limit = yes]
 fcntl-h         [test $gl_cv_have_arbitrary_file_name_length_limit = yes]
--- modules/fchdir.orig Fri Sep 23 12:28:28 2011
+++ modules/fchdir      Fri Sep 23 12:21:33 2011
@@ -7,6 +7,7 @@
 
 Depends-on:
 unistd
+chdir            [test $HAVE_FCHDIR = 0]
 close            [test $HAVE_FCHDIR = 0]
 dirent           [test $HAVE_FCHDIR = 0]
 dirfd            [test $HAVE_FCHDIR = 0]
--- modules/rename.orig Fri Sep 23 12:28:28 2011
+++ modules/rename      Fri Sep 23 12:20:35 2011
@@ -8,6 +8,7 @@
 Depends-on:
 stdio
 canonicalize-lgpl [test $REPLACE_RENAME = 1]
+chdir             [test $REPLACE_RENAME = 1]
 dirname-lgpl      [test $REPLACE_RENAME = 1]
 lstat             [test $REPLACE_RENAME = 1]
 rmdir             [test $REPLACE_RENAME = 1]
--- modules/savewd.orig Fri Sep 23 12:28:28 2011
+++ modules/savewd      Fri Sep 23 12:20:50 2011
@@ -7,6 +7,7 @@
 m4/savewd.m4
 
 Depends-on:
+chdir
 dosname
 errno
 fchdir
--- modules/unistd.orig Fri Sep 23 12:28:28 2011
+++ modules/unistd      Fri Sep 23 12:23:10 2011
@@ -30,6 +30,7 @@
              -e 's|@''PRAGMA_SYSTEM_HEADER''@|@PRAGMA_SYSTEM_HEADER@|g' \
              -e 's|@''PRAGMA_COLUMNS''@|@PRAGMA_COLUMNS@|g' \
              -e 's|@''NEXT_UNISTD_H''@|$(NEXT_UNISTD_H)|g' \
+             -e 's/@''GNULIB_CHDIR''@/$(GNULIB_CHDIR)/g' \
              -e 's/@''GNULIB_CHOWN''@/$(GNULIB_CHOWN)/g' \
              -e 's/@''GNULIB_CLOSE''@/$(GNULIB_CLOSE)/g' \
              -e 's/@''GNULIB_DUP2''@/$(GNULIB_DUP2)/g' \
--- tests/test-unistd-c++.cc.orig       Fri Sep 23 12:28:28 2011
+++ tests/test-unistd-c++.cc    Fri Sep 23 12:17:40 2011
@@ -24,6 +24,10 @@
 #include "signature.h"
 
 
+#if GNULIB_TEST_CHDIR
+SIGNATURE_CHECK (GNULIB_NAMESPACE::chdir, int, (const char *));
+#endif
+
 #if GNULIB_TEST_CHOWN
 SIGNATURE_CHECK (GNULIB_NAMESPACE::chown, int, (const char *, uid_t, gid_t));
 #endif
-- 
In memoriam Ghazala Khan <http://en.wikipedia.org/wiki/Ghazala_Khan>