+(defun nnrss-find-el (tag data &optional found-list)
+ "Find the all matching elements in the data.
+Careful with this on large documents!"
+ (when (consp data)
+ (dolist (bit data)
+ (when (car-safe bit)
+ (when (equal tag (car bit))
+ ;; Old xml.el may return a list of string.
+ (when (and (consp (caddr bit))
+ (stringp (caaddr bit)))
+ (setcar (cddr bit) (caaddr bit)))
+ (setq found-list
+ (append found-list
+ (list bit))))
+ (if (and (consp (car-safe (caddr bit)))
+ (not (stringp (caddr bit))))
+ (setq found-list
+ (append found-list
+ (nnrss-find-el
+ tag (caddr bit))))
+ (setq found-list
+ (append found-list
+ (nnrss-find-el
+ tag (cddr bit))))))))
+ found-list)
+
+(defun nnrss-rsslink-p (el)
+ "Test if the element we are handed is an RSS autodiscovery link."
+ (and (eq (car-safe el) 'link)
+ (string-equal (cdr (assoc 'rel (cadr el))) "alternate")
+ (or (string-equal (cdr (assoc 'type (cadr el)))
+ "application/rss+xml")
+ (string-equal (cdr (assoc 'type (cadr el))) "text/xml"))))
+
+(defun nnrss-get-rsslinks (data)
+ "Extract the <link> elements that are links to RSS from the parsed data."
+ (delq nil (mapcar
+ (lambda (el)
+ (if (nnrss-rsslink-p el) el))
+ (nnrss-find-el 'link data))))
+
+(defun nnrss-extract-hrefs (data)
+ "Recursively extract hrefs from a page's source.
+DATA should be the output of `xml-parse-region' or
+`w3-parse-buffer'."
+ (mapcar (lambda (ahref)
+ (cdr (assoc 'href (cadr ahref))))
+ (nnrss-find-el 'a data)))
+
+(defmacro nnrss-match-macro (base-uri item onsite-list offsite-list)
+ `(cond ((or (string-match (concat "^" ,base-uri) ,item)
+ (not (string-match "://" ,item)))
+ (setq ,onsite-list (append ,onsite-list (list ,item))))
+ (t (setq ,offsite-list (append ,offsite-list (list ,item))))))
+
+(defun nnrss-order-hrefs (base-uri hrefs)
+ "Given a list of hrefs, sort them using the following priorities:
+ 1. links ending in .rss
+ 2. links ending in .rdf
+ 3. links ending in .xml
+ 4. links containing the above
+ 5. offsite links
+
+BASE-URI is used to determine the location of the links and
+whether they are `offsite' or `onsite'."
+ (let (rss-onsite-end rdf-onsite-end xml-onsite-end
+ rss-onsite-in rdf-onsite-in xml-onsite-in
+ rss-offsite-end rdf-offsite-end xml-offsite-end
+ rss-offsite-in rdf-offsite-in xml-offsite-in)
+ (dolist (href hrefs)
+ (cond ((null href))
+ ((string-match "\\.rss$" href)
+ (nnrss-match-macro
+ base-uri href rss-onsite-end rss-offsite-end))
+ ((string-match "\\.rdf$" href)
+ (nnrss-match-macro
+ base-uri href rdf-onsite-end rdf-offsite-end))
+ ((string-match "\\.xml$" href)
+ (nnrss-match-macro
+ base-uri href xml-onsite-end xml-offsite-end))
+ ((string-match "rss" href)
+ (nnrss-match-macro
+ base-uri href rss-onsite-in rss-offsite-in))
+ ((string-match "rdf" href)
+ (nnrss-match-macro
+ base-uri href rdf-onsite-in rdf-offsite-in))
+ ((string-match "xml" href)
+ (nnrss-match-macro
+ base-uri href xml-onsite-in xml-offsite-in))))
+ (append
+ rss-onsite-end rdf-onsite-end xml-onsite-end
+ rss-onsite-in rdf-onsite-in xml-onsite-in
+ rss-offsite-end rdf-offsite-end xml-offsite-end
+ rss-offsite-in rdf-offsite-in xml-offsite-in)))
+
+(defun nnrss-discover-feed (url)
+ "Given a page, find an RSS feed using Mark Pilgrim's
+`ultra-liberal rss locator' (http://diveintomark.org/2002/08/15.html)."
+
+ (let ((parsed-page (nnrss-fetch url)))
+
+;; 1. if this url is the rss, use it.
+ (if (nnrss-rss-p parsed-page)
+ (let ((rss-ns (nnrss-get-namespace-prefix parsed-page "http://purl.org/rss/1.0/")))
+ (nnrss-rss-title-description rss-ns parsed-page url))
+
+;; 2. look for the <link rel="alternate"
+;; type="application/rss+xml" and use that if it is there.
+ (let ((links (nnrss-get-rsslinks parsed-page)))
+ (if links
+ (let* ((xml (nnrss-fetch
+ (cdr (assoc 'href (cadar links)))))
+ (rss-ns (nnrss-get-namespace-prefix xml "http://purl.org/rss/1.0/")))
+ (nnrss-rss-title-description rss-ns xml (cdr (assoc 'href (cadar links)))))
+
+;; 3. look for links on the site in the following order:
+;; - onsite links ending in .rss, .rdf, or .xml
+;; - onsite links containing any of the above
+;; - offsite links ending in .rss, .rdf, or .xml
+;; - offsite links containing any of the above
+ (let* ((base-uri (progn (string-match ".*://[^/]+/?" url)
+ (match-string 0 url)))
+ (hrefs (nnrss-order-hrefs
+ base-uri (nnrss-extract-hrefs parsed-page)))
+ (rss-link nil))
+ (while (and (eq rss-link nil) (not (eq hrefs nil)))
+ (let ((href-data (nnrss-fetch (car hrefs))))
+ (if (nnrss-rss-p href-data)
+ (let* ((rss-ns (nnrss-get-namespace-prefix href-data "http://purl.org/rss/1.0/")))
+ (setq rss-link (nnrss-rss-title-description
+ rss-ns href-data (car hrefs))))
+ (setq hrefs (cdr hrefs)))))
+ (if rss-link rss-link
+
+;; 4. check syndic8
+ (nnrss-find-rss-via-syndic8 url))))))))
+
+(defun nnrss-find-rss-via-syndic8 (url)
+ "Query syndic8 for the rss feeds it has for URL."
+ (if (not (locate-library "xml-rpc"))
+ (progn
+ (message "XML-RPC is not available... not checking Syndic8.")
+ nil)
+ (require 'xml-rpc)
+ (let ((feedid (xml-rpc-method-call
+ "http://www.syndic8.com/xmlrpc.php"
+ 'syndic8.FindSites
+ url)))
+ (when feedid
+ (let* ((feedinfo (xml-rpc-method-call
+ "http://www.syndic8.com/xmlrpc.php"
+ 'syndic8.GetFeedInfo
+ feedid))
+ (urllist
+ (delq nil
+ (mapcar
+ (lambda (listinfo)
+ (if (string-equal
+ (cdr (assoc "status" listinfo))
+ "Syndicated")
+ (cons
+ (cdr (assoc "sitename" listinfo))
+ (list
+ (cons 'title
+ (cdr (assoc
+ "sitename" listinfo)))
+ (cons 'href
+ (cdr (assoc
+ "dataurl" listinfo)))))))
+ feedinfo))))
+ (if (not (> (length urllist) 1))
+ (cdar urllist)
+ (let ((completion-ignore-case t)
+ (selection
+ (mapcar (lambda (listinfo)
+ (cons (cdr (assoc "sitename" listinfo))
+ (string-to-number
+ (cdr (assoc "feedid" listinfo)))))
+ feedinfo)))
+ (cdr (assoc
+ (completing-read
+ "Multiple feeds found. Select one: "
+ selection nil t) urllist)))))))))
+
+(defun nnrss-rss-p (data)
+ "Test if DATA is an RSS feed.
+Simply ensures that the first element is rss or rdf."
+ (or (eq (caar data) 'rss)
+ (eq (caar data) 'rdf:RDF)))
+
+(defun nnrss-rss-title-description (rss-namespace data url)
+ "Return the title of an RSS feed."
+ (if (nnrss-rss-p data)
+ (let ((description (intern (concat rss-namespace "description")))
+ (title (intern (concat rss-namespace "title")))
+ (channel (nnrss-find-el (intern (concat rss-namespace "channel"))
+ data)))
+ (list
+ (cons 'description (caddr (nth 0 (nnrss-find-el description channel))))
+ (cons 'title (caddr (nth 0 (nnrss-find-el title channel))))
+ (cons 'href url)))))
+
+(defun nnrss-get-namespace-prefix (el uri)
+ "Given EL (containing a parsed element) and URI (containing a string
+that gives the URI for which you want to retrieve the namespace
+prefix), return the prefix."
+ (let* ((prefix (car (rassoc uri (cadar el))))
+ (nslist (if prefix
+ (split-string (symbol-name prefix) ":")))
+ (ns (cond ((eq (length nslist) 1) ; no prefix given
+ "")
+ ((eq (length nslist) 2) ; extract prefix
+ (cadr nslist)))))
+ (if (and ns (not (string= ns "")))
+ (concat ns ":")
+ ns)))
+
projects / gnus / blobdiff