+ dnl If lstat does not exist, the replacement <sys/stat.h> does
+ dnl "#define lstat stat", and lstat.c is a no-op.
+ AC_CHECK_FUNCS_ONCE([lstat])
+ if test $ac_cv_func_lstat = yes; then
+ AC_REQUIRE([AC_FUNC_LSTAT_FOLLOWS_SLASHED_SYMLINK])
+ if test $ac_cv_func_lstat_dereferences_slashed_symlink = no; then
+ dnl Note: AC_FUNC_LSTAT_FOLLOWS_SLASHED_SYMLINK does AC_LIBOBJ([lstat]).
+ REPLACE_LSTAT=1
+ fi
+ # Prerequisites of lib/lstat.c.
+ AC_REQUIRE([AC_C_INLINE])
+ else
+ HAVE_LSTAT=0
+ fi
+])
+
+# Redefine AC_FUNC_LSTAT_FOLLOWS_SLASHED_SYMLINK, because it is no longer
+# maintained in Autoconf.
+AC_DEFUN([AC_FUNC_LSTAT_FOLLOWS_SLASHED_SYMLINK],
+[
+ AC_CACHE_CHECK([whether lstat correctly handles trailing slash],
+ [ac_cv_func_lstat_dereferences_slashed_symlink],
+ [rm -f conftest.sym conftest.file
+ echo >conftest.file
+ if test "$as_ln_s" = "ln -s" && ln -s conftest.file conftest.sym; then
+ AC_RUN_IFELSE(
+ [AC_LANG_PROGRAM(
+ [AC_INCLUDES_DEFAULT],
+ [[struct stat sbuf;
+ /* Linux will dereference the symlink and fail, as required by
+ POSIX. That is better in the sense that it means we will not
+ have to compile and use the lstat wrapper. */
+ return lstat ("conftest.sym/", &sbuf) == 0;
+ ]])],
+ [ac_cv_func_lstat_dereferences_slashed_symlink=yes],
+ [ac_cv_func_lstat_dereferences_slashed_symlink=no],
+ [# When cross-compiling, be pessimistic so we will end up using the
+ # replacement version of lstat that checks for trailing slashes and
+ # calls lstat a second time when necessary.
+ ac_cv_func_lstat_dereferences_slashed_symlink=no
+ ])
+ else
+ # If the 'ln -s' command failed, then we probably don't even
+ # have an lstat function.
+ ac_cv_func_lstat_dereferences_slashed_symlink=no
+ fi
+ rm -f conftest.sym conftest.file
+ ])
+ test $ac_cv_func_lstat_dereferences_slashed_symlink = yes &&
+ AC_DEFINE_UNQUOTED([LSTAT_FOLLOWS_SLASHED_SYMLINK], [1],
+ [Define to 1 if `lstat' dereferences a symlink specified
+ with a trailing slash.])
+ if test "x$ac_cv_func_lstat_dereferences_slashed_symlink" = xno; then
+ AC_LIBOBJ([lstat])