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authorJörg Frings-Fürst <debian@jff.email>2024-10-20 15:21:43 +0200
committerJörg Frings-Fürst <debian@jff.email>2024-10-20 15:21:43 +0200
commit4682deeb62247d34de87f8e777f99e2d337fd377 (patch)
tree5bd5b5605b5f3a4b3c8ea7468c34c23094afdef4 /gnulib-m4/dirfd.m4
parent00893e79fc62966067af1a106567db96bd170338 (diff)
New upstream version 1.3upstream/1.3upstream
Diffstat (limited to 'gnulib-m4/dirfd.m4')
-rw-r--r--gnulib-m4/dirfd.m488
1 files changed, 88 insertions, 0 deletions
diff --git a/gnulib-m4/dirfd.m4 b/gnulib-m4/dirfd.m4
new file mode 100644
index 00000000..605cb706
--- /dev/null
+++ b/gnulib-m4/dirfd.m4
@@ -0,0 +1,88 @@
+# dirfd.m4
+# serial 30 -*- Autoconf -*-
+dnl Copyright (C) 2001-2006, 2008-2024 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.
+
+dnl Find out how to get the file descriptor associated with an open DIR*.
+
+dnl From Jim Meyering
+
+AC_DEFUN([gl_FUNC_DIRFD],
+[
+ AC_REQUIRE([gl_DIRENT_H_DEFAULTS])
+ AC_REQUIRE([AC_CANONICAL_HOST])
+
+ dnl Persuade glibc <dirent.h> to declare dirfd().
+ AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])
+
+ AC_CHECK_FUNCS([dirfd])
+ AC_CHECK_DECLS([dirfd], , ,
+ [[#include <sys/types.h>
+ #include <dirent.h>]])
+ if test $ac_cv_have_decl_dirfd = no; then
+ HAVE_DECL_DIRFD=0
+ fi
+
+ AC_CACHE_CHECK([whether dirfd is a macro],
+ [gl_cv_func_dirfd_macro],
+ [AC_EGREP_CPP([dirent_header_defines_dirfd], [
+#include <sys/types.h>
+#include <dirent.h>
+#ifdef dirfd
+ dirent_header_defines_dirfd
+#endif],
+ [gl_cv_func_dirfd_macro=yes],
+ [gl_cv_func_dirfd_macro=no])])
+
+ if test $ac_cv_func_dirfd = no && test $gl_cv_func_dirfd_macro = no; then
+ HAVE_DIRFD=0
+ else
+ HAVE_DIRFD=1
+ dnl Replace dirfd() on native Windows and OS/2 kLIBC,
+ dnl to support fdopendir().
+ AC_REQUIRE([gl_DIRENT_DIR])
+ if test $DIR_HAS_FD_MEMBER = 0; then
+ REPLACE_DIRFD=1
+ fi
+ fi
+])
+
+dnl Prerequisites of lib/dirfd.c.
+AC_DEFUN([gl_PREREQ_DIRFD],
+[
+ AC_CACHE_CHECK([how to get the file descriptor associated with an open DIR*],
+ [gl_cv_sys_dir_fd_member_name],
+ [
+ gl_saved_CFLAGS=$CFLAGS
+ for ac_expr in d_fd dd_fd; do
+
+ CFLAGS="$CFLAGS -DDIR_FD_MEMBER_NAME=$ac_expr"
+ AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
+ #include <sys/types.h>
+ #include <dirent.h>]],
+ [[DIR *dir_p = opendir("."); (void) dir_p->DIR_FD_MEMBER_NAME;]])],
+ [dir_fd_found=yes]
+ )
+ CFLAGS=$gl_saved_CFLAGS
+ test "$dir_fd_found" = yes && break
+ done
+ test "$dir_fd_found" = yes || ac_expr=no_such_member
+
+ gl_cv_sys_dir_fd_member_name=$ac_expr
+ ]
+ )
+ if test $gl_cv_sys_dir_fd_member_name != no_such_member; then
+ AC_DEFINE_UNQUOTED([DIR_FD_MEMBER_NAME],
+ [$gl_cv_sys_dir_fd_member_name],
+ [the name of the file descriptor member of DIR])
+ fi
+ AH_VERBATIM([DIR_TO_FD],
+ [#ifdef DIR_FD_MEMBER_NAME
+# define DIR_TO_FD(Dir_p) ((Dir_p)->DIR_FD_MEMBER_NAME)
+#else
+# define DIR_TO_FD(Dir_p) -1
+#endif
+])
+])