hsx/src/util.lisp

98 lines
3 KiB
Common Lisp

(uiop:define-package #:piccolo/util
(:use #:cl)
(:export
;;; list utility
#:plist-alist
#:alist-plist
;;; escape utility
#:*escape-html*
#:utf8-html-escape-char-p
#:ascii-html-escape-char-p
#:attr-value-escape-char-p
#:escape-string
#:escape-attrs-alist
#:escape-children
;;; syntax tree utility
#:modify-first-leaves))
(in-package #:piccolo/util)
(defun plist-alist (plist)
(loop for (k v) on plist by #'cddr
collect (cons k v)))
(defun alist-plist (alist)
(mapcan (lambda (kv)
(list (string-downcase (car kv))
(cdr kv)))
alist))
(defvar *escape-html* :utf8
"Specify the escape option when generate html, can be :UTF8, :ASCII, :ATTR or NIL.
If :UTF8, escape only #\<, #\> and #\& in body, and \" in attribute keys. #\' will
in attribute keys will not be escaped since piccolo will always use double quote for
attribute keys.
If :ASCII, besides what escaped in :UTF8, also escape all non-ascii characters.
If :ATTR, only #\" in attribute values will be escaped.
If NIL, nothing is escaped and programmer is responsible to escape elements properly.
When given :ASCII and :ATTR, it's possible to insert html text as a children, e.g.
(div :id \"container\" \"Some <b>text</b>\")")
(defun utf8-html-escape-char-p (char)
(find char "<>&"))
(defun ascii-html-escape-char-p (char)
(or (utf8-html-escape-char-p char)
(> (char-code char) 127)))
(defun attr-value-escape-char-p (char)
(eql char #\"))
(defun escape-char (char)
(case char
(#\< "&lt;")
(#\> "&gt;")
(#\& "&amp;")
(#\' "&#039;")
(#\" "&quot;")
(t (format nil "&#~d;" (char-code char)))))
(defun escape-string (string &optional (test #'utf8-html-escape-char-p))
(if (stringp string)
(with-output-to-string (s)
(loop
for c across string
do (write (if (funcall test c) (escape-char c) c) :stream s :escape nil)))
string))
(defun escape-attrs-alist (alist)
(mapcar (lambda (kv)
(cons (car kv)
(escape-string (cdr kv) #'attr-value-escape-char-p)))
alist))
(defun escape-children (children)
(mapcar (lambda (child)
(if (stringp child)
(case *escape-html*
(:utf8 (escape-string child))
(:ascii (escape-string child #'ascii-html-escape-char-p))
(otherwise child))
child))
children))
(defun modify-first-leaves (tree test result)
(if tree
(cons (let ((first-node (first tree)))
(cond
((listp first-node)
(modify-first-leaves first-node test result))
((funcall test first-node)
(funcall result first-node))
(t first-node)))
(mapcar (lambda (node)
(if (listp node)
(modify-first-leaves node test result)
node))
(rest tree)))))