summaryrefslogtreecommitdiffstats
path: root/gl/m4/fchdir.m4
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--gl/m4/fchdir.m466
1 files changed, 66 insertions, 0 deletions
diff --git a/gl/m4/fchdir.m4 b/gl/m4/fchdir.m4
new file mode 100644
index 0000000..f85549a
--- /dev/null
+++ b/gl/m4/fchdir.m4
@@ -0,0 +1,66 @@
+# fchdir.m4 serial 27
+dnl Copyright (C) 2006-2022 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_FCHDIR],
+[
+ AC_REQUIRE([gl_UNISTD_H_DEFAULTS])
+ AC_REQUIRE([gl_DIRENT_H_DEFAULTS])
+ AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
+
+ AC_CHECK_DECLS_ONCE([fchdir])
+ if test $ac_cv_have_decl_fchdir = no; then
+ HAVE_DECL_FCHDIR=0
+ fi
+
+ AC_REQUIRE([gl_TEST_FCHDIR])
+ if test $HAVE_FCHDIR = 0; then
+ AC_DEFINE([REPLACE_FCHDIR], [1],
+ [Define to 1 if gnulib's fchdir() replacement is used.])
+ dnl We must also replace anything that can manipulate a directory fd,
+ dnl to keep our bookkeeping up-to-date. We don't have to replace
+ dnl fstatat, since no platform has fstatat but lacks fchdir.
+ AC_CACHE_CHECK([whether open can visit directories],
+ [gl_cv_func_open_directory_works],
+ [AC_RUN_IFELSE(
+ [AC_LANG_PROGRAM(
+ [[#include <fcntl.h>
+ ]GL_MDA_DEFINES],
+ [[return open(".", O_RDONLY) < 0;]])],
+ [gl_cv_func_open_directory_works=yes],
+ [gl_cv_func_open_directory_works=no],
+ [case "$host_os" in
+ # Guess yes on Linux systems.
+ linux-* | linux) gl_cv_func_open_directory_works="guessing yes" ;;
+ # Guess yes on glibc systems.
+ *-gnu* | gnu*) gl_cv_func_open_directory_works="guessing yes" ;;
+ # Guess no on native Windows.
+ mingw*) gl_cv_func_open_directory_works="guessing no" ;;
+ # If we don't know, obey --enable-cross-guesses.
+ *) gl_cv_func_open_directory_works="$gl_cross_guess_normal" ;;
+ esac
+ ])])
+ case "$gl_cv_func_open_directory_works" in
+ *yes) ;;
+ *)
+ AC_DEFINE([REPLACE_OPEN_DIRECTORY], [1], [Define to 1 if open() should
+work around the inability to open a directory.])
+ ;;
+ esac
+ fi
+])
+
+# Determine whether to use the overrides in lib/fchdir.c.
+AC_DEFUN([gl_TEST_FCHDIR],
+[
+ AC_REQUIRE([gl_UNISTD_H_DEFAULTS])
+ AC_CHECK_FUNCS_ONCE([fchdir])
+ if test $ac_cv_func_fchdir = no; then
+ HAVE_FCHDIR=0
+ fi
+])
+
+# Prerequisites of lib/fchdir.c.
+AC_DEFUN([gl_PREREQ_FCHDIR], [:])