feat(third_party/lisp/s-xml): Check in sources & derivation

Checked in the sources for this because it is tracked upstream in CVS
and I can't be bothered to deal with that right now.

third_party/lisp/s-xml/src/sxml-dom.lisp

@@ -0,0 +1,76 @@
+;;;; -*- mode: lisp -*-
+;;;;
+;;;; $Id: sxml-dom.lisp,v 1.4 2005/09/20 09:57:48 scaekenberghe Exp $
+;;;;
+;;;; LXML implementation of the generic DOM parser and printer.
+;;;;
+;;;; Copyright (C) 2003, 2004 Sven Van Caekenberghe, Beta Nine BVBA.
+;;;;
+;;;; You are granted the rights to distribute and use this software
+;;;; as governed by the terms of the Lisp Lesser General Public License
+;;;; (http://opensource.franz.com/preamble.html), also known as the LLGPL.
+
+(in-package :s-xml)
+
+;;; the sxml hooks to generate sxml
+
+(defun sxml-new-element-hook (name attributes seed)
+  (declare (ignore name attributes seed))
+  '())
+
+(defun sxml-finish-element-hook (name attributes parent-seed seed)
+  (let ((xml-element (append (list name)
+			     (when attributes
+			       (list (let (list)
+				       (dolist (attribute attributes (cons :@ list))
+					 (push (list (car attribute) (cdr attribute)) list)))))
+			     (nreverse seed))))
+    (cons xml-element parent-seed)))
+
+(defun sxml-text-hook (string seed)
+  (cons string seed))
+
+;;; the standard DOM interfaces
+
+(defmethod parse-xml-dom (stream (output-type (eql :sxml)))
+  (car (start-parse-xml stream
+			(make-instance 'xml-parser-state
+				       :new-element-hook #'sxml-new-element-hook
+				       :finish-element-hook #'sxml-finish-element-hook
+				       :text-hook #'sxml-text-hook))))
+
+(defmethod print-xml-dom (dom (input-type (eql :sxml)) stream pretty level)
+  (declare (special *namespaces*))
+  (cond ((stringp dom) (print-string-xml dom stream))
+	((consp dom)
+	 (let ((tag (first dom))
+	       attributes
+	       children)
+	   (if (and (consp (second dom)) (eq (first (second dom)) :@))
+	       (setf attributes (rest (second dom))
+		     children (rest (rest dom)))
+	     (setf children (rest dom)))
+           (let ((*namespaces* (extend-namespaces (loop :for (name value) :in attributes 
+                                                        :collect (cons name value))
+                                                  *namespaces*)))
+             (write-char #\< stream)
+             (print-identifier tag stream)
+             (loop :for (name value) :in attributes
+                   :do (print-attribute name value stream))
+             (if children
+                 (progn
+                   (write-char #\> stream)
+                   (if (and (= (length children) 1) (stringp (first children)))
+                       (print-string-xml (first children) stream)
+                     (progn
+                       (dolist (child children)
+                         (when pretty (print-spaces (* 2 level) stream))
+                         (if (stringp child)
+                             (print-string-xml child stream)
+                           (print-xml-dom child input-type stream pretty (1+ level))))
+                       (when pretty (print-spaces (* 2 (1- level)) stream))))
+                   (print-closing-tag tag stream))
+               (write-string "/>" stream)))))
+	(t (error "Input not recognized as SXML ~s" dom))))
+
+;;;; eof