htmlize-faces-in-buffer

htmlize-faces-in-buffer is a Lisp function in `htmlize.el'.

(htmlize-faces-in-buffer)

Return a list of faces used in the current buffer.
Under XEmacs, this returns the set of faces specified by the extents
with the `face' property. (This covers text properties as well.) Under
GNU Emacs, it returns the set of faces specified by the `face' text
property and by buffer overlays that specify `face'.