1 files changed, 57 insertions, 0 deletions
diff --git a/m4/symlink.m4 b/m4/symlink.m4
new file mode 100644
index 0000000..52d6c11
--- /dev/null
+++ b/m4/symlink.m4
@@ -0,0 +1,57 @@
+# serial 10
+# See if we need to provide symlink replacement.
+
+dnl Copyright (C) 2009-2023 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.
+
+# Written by Eric Blake.
+
+AC_DEFUN([gl_FUNC_SYMLINK],
+[
+  AC_REQUIRE([gl_UNISTD_H_DEFAULTS])
+  AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
+  AC_CHECK_FUNCS_ONCE([symlink])
+  dnl The best we can do on mingw is provide a dummy that always fails, so
+  dnl that compilation can proceed with fewer ifdefs.  On FreeBSD 7.2, AIX 7.1,
+  dnl and Solaris 9, we want to fix a bug with trailing slash handling.
+  if test $ac_cv_func_symlink = no; then
+    HAVE_SYMLINK=0
+  else
+    AC_CACHE_CHECK([whether symlink handles trailing slash correctly],
+      [gl_cv_func_symlink_works],
+      [AC_RUN_IFELSE(
+         [AC_LANG_PROGRAM(
+           [[#include <unistd.h>
+           ]],
+           [[int result = 0;
+             if (!symlink ("a", "conftest.link/"))
+               result |= 1;
+             if (symlink ("conftest.f", "conftest.lnk2"))
+               result |= 2;
+             else if (!symlink ("a", "conftest.lnk2/"))
+               result |= 4;
+             return result;
+           ]])],
+         [gl_cv_func_symlink_works=yes], [gl_cv_func_symlink_works=no],
+         [case "$host_os" in
+                             # Guess yes on Linux systems.
+            linux-* | linux) gl_cv_func_symlink_works="guessing yes" ;;
+                             # Guess yes on systems that emulate the Linux system calls.
+            midipix*)        gl_cv_func_symlink_works="guessing yes" ;;
+                             # Guess yes on glibc systems.
+            *-gnu* | gnu*)   gl_cv_func_symlink_works="guessing yes" ;;
+                             # If we don't know, obey --enable-cross-guesses.
+            *)               gl_cv_func_symlink_works="$gl_cross_guess_normal" ;;
+          esac
+         ])
+      rm -f conftest.f conftest.link conftest.lnk2])
+    case "$gl_cv_func_symlink_works" in
+      *yes) ;;
+      *)
+        REPLACE_SYMLINK=1
+        ;;
+    esac
+  fi
+])