Filtering feature for variable substitution in output.

* filter.c, filter.h: New files.

* Makefile (OBJS): filter.o added.

* gc.c (mark_obj): Mark new alloc field of string objets.

* hash.c (struct hash): New member, userdata.
(hash_mark): Mark new userdata member of hash.
(make_hash): Initialize userdata.
(get_hash_userdata, set_hash_userdata, hashp): New functions.

* hash.h (get_hash_userdata, set_hash_userdata, hashp): New functions
declared.

* lib.c (getplist, string_extend, cobjp): New functions.
(string_own, string, string_utf8): Initialize new alloc field to nil.
(mkstring, mkustring): Initialize new alloc field to actual size.
(length_str): When length is computed and cached, also compute
and cache alloc.
(init): Call filter_init.

* lib.h (string string): New member, alloc.
(num_fast): Macro converted to inline function.
(getplist, string_extend, cobjp): New functions declared.

* match.c (match_line): Follows change of modifier s-exp syntax.
(format_field): New parameter, filter.
New modifier syntax parsed. Filter retrieved, and applied.
(subst_vars): New parameter, filter. Filter is either applied
in this function or passed to format_field, as needed.
(eval_form): Pass nil to new parameter of subst_vars.
(do_output_line): New parameter, filter. Passed down to subst_vars.
(do_output): New parameter, filter. Passed down to do_output_line.
(match_files): Pass nil filter to subst_vars in cat directive.
Output directive refactored to parse keywords, extract the
filter and pass down to do_output.

* parser.y (regex): Generate (sys:regex regex syntax ...)
instead of (regex syntax ...).
(elem, expr): Updated w.r.t. regex syntax change.
(var): Cases '{' IDENT regex '}' and '{' IDENT NUMBER '}'
are removed. new syntax '{' IDENT exprs '}' to handle these
more generally and allow for keywords.

* txr.1: Updated.

1 files changed, 36 insertions, 0 deletions

diff --git a/filter.h b/filter.h
new file mode 100644
index 00000000..f8d86632
--- /dev/null
+++ b/filter.h
@@ -0,0 +1,36 @@
+/* Copyright 2011
+ * Kaz Kylheku <kkylheku@gmail.com>
+ * Vancouver, Canada
+ * All rights reserved.
+ *
+ * BSD License:
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ *   1. Redistributions of source code must retain the above copyright
+ *      notice, this list of conditions and the following disclaimer.
+ *   2. Redistributions in binary form must reproduce the above copyright
+ *      notice, this list of conditions and the following disclaimer in
+ *      the documentation and/or other materials provided with the
+ *      distribution.
+ *   3. The name of the author may not be used to endorse or promote
+ *      products derived from this software without specific prior
+ *      written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+extern val filters;
+extern val filter_k, to_html_k;
+
+val trie_lookup_begin(val trie);
+val trie_value_at(val node);
+val trie_lookup_feed_char(val node, val ch);
+val get_filter_trie(val sym);
+val filter_string(val trie, val str);
+
+void filter_init(void);