+#define obstack_chunk_alloc xmalloc
+#define obstack_chunk_free free
+#include <obstack.h>
+
+/* String-grow: append Str to Obs. */
+
+#define obstack_sgrow(Obs, Str) \
+ obstack_grow (Obs, Str, strlen (Str))
+
+/* Output Str escaped for our postprocessing (i.e., escape M4 special
+ characters).
+
+ For instance "[foo]" -> "@{foo@}", "$$" -> "$][$][". */
+
+# define obstack_escape(Obs, Str) \
+ do { \
+ char const *p__; \
+ for (p__ = Str; *p__; p__++) \
+ switch (*p__) \
+ { \
+ case '$': obstack_sgrow (Obs, "$]["); break; \
+ case '@': obstack_sgrow (Obs, "@@" ); break; \
+ case '[': obstack_sgrow (Obs, "@{" ); break; \
+ case ']': obstack_sgrow (Obs, "@}" ); break; \
+ default: obstack_1grow (Obs, *p__ ); break; \
+ } \
+ } while (0)
+
+
+/* Output Str both quoted for M4 (i.e., embed in [[...]]), and escaped
+ for our postprocessing (i.e., escape M4 special characters). If
+ Str is empty (or NULL), output "[]" instead of "[[]]" as it make M4
+ programming easier (m4_ifval can be used).
+
+ For instance "[foo]" -> "[[@{foo@}]]", "$$" -> "[[$][$][]]". */
+
+# define obstack_quote(Obs, Str) \
+ do { \
+ char const* obstack_quote_p = Str; \
+ if (obstack_quote_p && obstack_quote_p[0]) \
+ { \
+ obstack_sgrow (Obs, "[["); \
+ obstack_escape (Obs, obstack_quote_p); \
+ obstack_sgrow (Obs, "]]"); \
+ } \
+ else \
+ obstack_sgrow (Obs, "[]"); \
+ } while (0)
+
+
+/* Append the ending 0, finish Obs, and return the string. */
+
+# define obstack_finish0(Obs) \
+ (obstack_1grow (Obs, '\0'), (char *) obstack_finish (Obs))
+
+
+/*-----------------------------------------.
+| Extensions to use for the output files. |
+`-----------------------------------------*/
+
+#ifndef OUTPUT_EXT
+# define OUTPUT_EXT ".output"