1 files changed, 94 insertions, 0 deletions
diff --git a/m4/canonicalize.m4 b/m4/canonicalize.m4
new file mode 100644
index 0000000..dcc6039
--- /dev/null
+++ b/m4/canonicalize.m4
@@ -0,0 +1,94 @@
+# canonicalize.m4 serial 17
+
+dnl Copyright (C) 2003-2007, 2009-2011 Free Software Foundation, Inc.
+
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+# Provides canonicalize_file_name and canonicalize_filename_mode, but does
+# not provide or fix realpath.
+AC_DEFUN([gl_FUNC_CANONICALIZE_FILENAME_MODE],
+[
+  AC_LIBOBJ([canonicalize])
+
+  AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
+  AC_CHECK_FUNCS_ONCE([canonicalize_file_name])
+  AC_REQUIRE([gl_DOUBLE_SLASH_ROOT])
+  AC_REQUIRE([gl_FUNC_REALPATH_WORKS])
+  if test $ac_cv_func_canonicalize_file_name = no; then
+    HAVE_CANONICALIZE_FILE_NAME=0
+  elif test "$gl_cv_func_realpath_works" != yes; then
+    REPLACE_CANONICALIZE_FILE_NAME=1
+  fi
+])
+
+# Provides canonicalize_file_name and realpath.
+AC_DEFUN([gl_CANONICALIZE_LGPL],
+[
+  AC_REQUIRE([gl_CANONICALIZE_LGPL_SEPARATE])
+  if test $ac_cv_func_canonicalize_file_name = no; then
+    HAVE_CANONICALIZE_FILE_NAME=0
+    AC_LIBOBJ([canonicalize-lgpl])
+    if test $ac_cv_func_realpath = no; then
+      HAVE_REALPATH=0
+    elif test "$gl_cv_func_realpath_works" != yes; then
+      REPLACE_REALPATH=1
+    fi
+  elif test "$gl_cv_func_realpath_works" != yes; then
+    AC_LIBOBJ([canonicalize-lgpl])
+    REPLACE_REALPATH=1
+    REPLACE_CANONICALIZE_FILE_NAME=1
+  fi
+])
+
+# Like gl_CANONICALIZE_LGPL, except prepare for separate compilation
+# (no AC_LIBOBJ).
+AC_DEFUN([gl_CANONICALIZE_LGPL_SEPARATE],
+[
+  AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
+  AC_CHECK_FUNCS_ONCE([canonicalize_file_name getcwd readlink])
+  AC_REQUIRE([gl_DOUBLE_SLASH_ROOT])
+  AC_REQUIRE([gl_FUNC_REALPATH_WORKS])
+  AC_CHECK_HEADERS_ONCE([sys/param.h])
+])
+
+# Check whether realpath works.  Assume that if a platform has both
+# realpath and canonicalize_file_name, but the former is broken, then
+# so is the latter.
+AC_DEFUN([gl_FUNC_REALPATH_WORKS],
+[
+  AC_CHECK_FUNCS_ONCE([realpath])
+  AC_CACHE_CHECK([whether realpath works], [gl_cv_func_realpath_works], [
+    touch conftest.a
+    AC_RUN_IFELSE([
+      AC_LANG_PROGRAM([[
+        #include <stdlib.h>
+      ]], [[
+        int result = 0;
+        {
+          char *name = realpath ("conftest.a", NULL);
+          if (!(name && *name == '/'))
+            result |= 1;
+        }
+        {
+          char *name = realpath ("conftest.b/../conftest.a", NULL);
+          if (name != NULL)
+            result |= 2;
+        }
+        {
+          char *name = realpath ("conftest.a/", NULL);
+          if (name != NULL)
+            result |= 4;
+        }
+        return result;
+      ]])
+    ], [gl_cv_func_realpath_works=yes], [gl_cv_func_realpath_works=no],
+       [gl_cv_func_realpath_works="guessing no"])
+  ])
+  if test "$gl_cv_func_realpath_works" = yes; then
+    AC_DEFINE([FUNC_REALPATH_WORKS], [1], [Define to 1 if realpath()
+      can malloc memory, always gives an absolute path, and handles
+      trailing slash correctly.])
+  fi
+])