--- /dev/null
+;;; format.el --- read and save files in multiple formats
+
+;; Copyright (c) 1994, 1995, 1997 Free Software Foundation
+
+;; Author: Boris Goldowsky <boris@gnu.ai.mit.edu>
+;; Keywords: extensions, dumped
+
+;; This file is part of XEmacs.
+
+;; XEmacs is free software; you can redistribute it and/or modify it
+;; under the terms of the GNU General Public License as published by
+;; the Free Software Foundation; either version 2, or (at your option)
+;; any later version.
+
+;; XEmacs is distributed in the hope that it will be useful, but
+;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+;; General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with XEmacs; see the file COPYING. If not, write to the Free
+;; Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+;; 02111-1307, USA.
+
+;;; Synched up with: Emacs 20.2.
+
+;;; Commentary:
+
+;; This file is dumped with XEmacs.
+
+;; This file defines a unified mechanism for saving & loading files stored
+;; in different formats. `format-alist' contains information that directs
+;; Emacs to call an encoding or decoding function when reading or writing
+;; files that match certain conditions.
+;;
+;; When a file is visited, its format is determined by matching the
+;; beginning of the file against regular expressions stored in
+;; `format-alist'. If this fails, you can manually translate the buffer
+;; using `format-decode-buffer'. In either case, the formats used are
+;; listed in the variable `buffer-file-format', and become the default
+;; format for saving the buffer. To save a buffer in a different format,
+;; change this variable, or use `format-write-file'.
+;;
+;; Auto-save files are normally created in the same format as the visited
+;; file, but the variable `auto-save-file-format' can be set to a
+;; particularly fast or otherwise preferred format to be used for
+;; auto-saving (or nil to do no encoding on auto-save files, but then you
+;; risk losing any text-properties in the buffer).
+;;
+;; You can manually translate a buffer into or out of a particular format
+;; with the functions `format-encode-buffer' and `format-decode-buffer'.
+;; To translate just the region use the functions `format-encode-region'
+;; and `format-decode-region'.
+;;
+;; You can define a new format by writing the encoding and decoding
+;; functions, and adding an entry to `format-alist'. See enriched.el for
+;; an example of how to implement a file format. There are various
+;; functions defined in this file that may be useful for writing the
+;; encoding and decoding functions:
+;; * `format-annotate-region' and `format-deannotate-region' allow a
+;; single alist of information to be used for encoding and decoding.
+;; The alist defines a correspondence between strings in the file
+;; ("annotations") and text-properties in the buffer.
+;; * `format-replace-strings' is similarly useful for doing simple
+;; string->string translations in a reversible manner.
+
+;;; Code:
+
+(put 'buffer-file-format 'permanent-local t)
+
+(defvar format-alist
+ '(
+; (image/jpeg "JPEG image" "\377\330\377\340\000\020JFIF"
+; image-decode-jpeg nil t image-mode)
+; (image/gif "GIF image" "GIF8[79]"
+; image-decode-gif nil t image-mode)
+; (image/png "Portable Network Graphics" "\211PNG"
+; image-decode-png nil t image-mode)
+; (image/x-xpm "XPM image" "/\\* XPM \\*/"
+; image-decode-xpm nil t image-mode)
+
+; ;; TIFF files have lousy magic
+; (image/tiff "TIFF image" "II\\*\000"
+; image-decode-tiff nil t image-mode) ;; TIFF 6.0 big-endian
+; (image/tiff "TIFF image" "MM\000\\*"
+; image-decode-tiff nil t image-mode) ;; TIFF 6.0 little-endian
+
+ (text/enriched "Extended MIME text/enriched format."
+ "Content-[Tt]ype:[ \t]*text/enriched"
+ enriched-decode enriched-encode t enriched-mode)
+ (text/richtext "Extended MIME obsolete text/richtext format."
+ "Content-[Tt]ype:[ \t]*text/richtext"
+ richtext-decode richtext-encode t enriched-mode)
+ (plain "ISO 8859-1 standard format, no text properties."
+ ;; Plain only exists so that there is an obvious neutral choice in
+ ;; the completion list.
+ nil nil nil nil nil)
+ ;; (ibm "IBM Code Page 850 (DOS)"
+ ;; "1\\(^\\)"
+ ;; "recode ibm-pc:latin1" "recode latin1:ibm-pc" t nil)
+ ;; (mac "Apple Macintosh"
+ ;; "1\\(^\\)"
+ ;; "recode mac:latin1" "recode latin1:mac" t nil)
+ ;; (hp "HP Roman8"
+ ;; "1\\(^\\)"
+ ;; "recode roman8:latin1" "recode latin1:roman8" t nil)
+ ;; (TeX "TeX (encoding)"
+ ;; "1\\(^\\)"
+ ;; iso-tex2iso iso-iso2tex t nil)
+ ;; (gtex "German TeX (encoding)"
+ ;; "1\\(^\\)"
+ ;; iso-gtex2iso iso-iso2gtex t nil)
+ ;; (html "HTML (encoding)"
+ ;; "1\\(^\\)"
+ ;; "recode html:latin1" "recode latin1:html" t nil)
+ ;; (rot13 "rot13"
+ ;; "1\\(^\\)"
+ ;; "tr a-mn-z n-za-m" "tr a-mn-z n-za-m" t nil)
+ ;; (duden "Duden Ersatzdarstellung"
+ ;; "1\\(^\\)"
+ ;; "diac" iso-iso2duden t nil)
+ ;; (de646 "German ASCII (ISO 646)"
+ ;; "1\\(^\\)"
+ ;; "recode iso646-ge:latin1" "recode latin1:iso646-ge" t nil)
+ ;; (denet "net German"
+ ;; "1\\(^\\)"
+ ;; iso-german iso-cvt-read-only t nil)
+ ;; (esnet "net Spanish"
+ ;; "1\\(^\\)"
+ ;; iso-spanish iso-cvt-read-only t nil)
+ )
+ "List of information about understood file formats.
+Elements are of the form \(NAME DOC-STR REGEXP FROM-FN TO-FN MODIFY MODE-FN).
+
+NAME is a symbol, which is stored in `buffer-file-format'.
+
+DOC-STR should be a single line providing more information about the
+ format. It is currently unused, but in the future will be shown to
+ the user if they ask for more information.
+
+REGEXP is a regular expression to match against the beginning of the file;
+ it should match only files in that format.
+
+FROM-FN is called to decode files in that format; it gets two args, BEGIN
+ and END, and can make any modifications it likes, returning the new
+ end. It must make sure that the beginning of the file no longer
+ matches REGEXP, or else it will get called again.
+ Alternatively, FROM-FN can be a string, which specifies a shell command
+ (including options) to be used as a filter to perform the conversion.
+
+TO-FN is called to encode a region into that format; it is passed three
+ arguments: BEGIN, END, and BUFFER. BUFFER is the original buffer that
+ the data being written came from, which the function could use, for
+ example, to find the values of local variables. TO-FN should either
+ return a list of annotations like `write-region-annotate-functions',
+ or modify the region and return the new end.
+ Alternatively, TO-FN can be a string, which specifies a shell command
+ (including options) to be used as a filter to perform the conversion.
+
+MODIFY, if non-nil, means the TO-FN wants to modify the region. If nil,
+ TO-FN will not make any changes but will instead return a list of
+ annotations.
+
+MODE-FN, if specified, is called when visiting a file with that format.")
+
+;;; Basic Functions (called from Lisp)
+
+(defun format-encode-run-method (method from to &optional buffer)
+ "Translate using function or shell script METHOD the text from FROM to TO.
+If METHOD is a string, it is a shell command;
+otherwise, it should be a Lisp function.
+BUFFER should be the buffer that the output originally came from."
+ (if (stringp method)
+ (save-current-buffer
+ (set-buffer buffer)
+ (with-output-to-temp-buffer "*Format Errors*"
+ (shell-command-on-region from to method t nil))
+ (point))
+ (funcall method from to buffer)))
+
+(defun format-decode-run-method (method from to &optional buffer)
+ "Decode using function or shell script METHOD the text from FROM to TO.
+If METHOD is a string, it is a shell command;
+otherwise, it should be a Lisp function."
+ (if (stringp method)
+ (progn
+ (with-output-to-temp-buffer "*Format Errors*"
+ (shell-command-on-region from to method t nil))
+ (point))
+ (funcall method from to)))
+
+(defun format-annotate-function (format from to orig-buf)
+ "Return annotations for writing region as FORMAT.
+FORMAT is a symbol naming one of the formats defined in `format-alist',
+it must be a single symbol, not a list like `buffer-file-format'.
+FROM and TO delimit the region to be operated on in the current buffer.
+ORIG-BUF is the original buffer that the data came from.
+This function works like a function on `write-region-annotate-functions':
+it either returns a list of annotations, or returns with a different buffer
+current, which contains the modified text to write.
+
+For most purposes, consider using `format-encode-region' instead."
+ ;; This function is called by write-region (actually build-annotations)
+ ;; for each element of buffer-file-format.
+ (let* ((info (assq format format-alist))
+ (to-fn (nth 4 info))
+ (modify (nth 5 info)))
+ (if to-fn
+ (if modify
+ ;; To-function wants to modify region. Copy to safe place.
+ (let ((copy-buf (get-buffer-create " *Format Temp*")))
+ (copy-to-buffer copy-buf from to)
+ (set-buffer copy-buf)
+ (format-insert-annotations write-region-annotations-so-far from)
+ (format-encode-run-method to-fn (point-min) (point-max) orig-buf)
+ nil)
+ ;; Otherwise just call function, it will return annotations.
+ (funcall to-fn from to orig-buf)))))
+
+(defun format-decode (format length &optional visit-flag)
+ "Decode text from any known FORMAT.
+FORMAT is a symbol appearing in `format-alist' or a list of such symbols,
+or nil, in which case this function tries to guess the format of the data by
+matching against the regular expressions in `format-alist'. After a match is
+found and the region decoded, the alist is searched again from the beginning
+for another match.
+
+Second arg LENGTH is the number of characters following point to operate on.
+If optional third arg VISIT-FLAG is true, set `buffer-file-format'
+to the list of formats used, and call any mode functions defined for those
+formats.
+
+Returns the new length of the decoded region.
+
+For most purposes, consider using `format-decode-region' instead.
+
+This function is called by insert-file-contents whenever a file is read."
+ (let ((mod (buffer-modified-p))
+ (begin (point))
+ (end (+ (point) length)))
+ (if (null format)
+ ;; Figure out which format it is in, remember list in `format'.
+ (let ((try format-alist))
+ (while try
+ (let* ((f (car try))
+ (regexp (nth 2 f))
+ (p (point)))
+ (if (and regexp (looking-at regexp)
+ (< (match-end 0) (+ begin length)))
+ (progn
+ (setq format (cons (car f) format))
+ ;; Decode it
+ (if (nth 3 f)
+ (setq end (format-decode-run-method (nth 3 f) begin end)))
+ ;; Call visit function if required
+ (if (and visit-flag (nth 6 f)) (funcall (nth 6 f) 1))
+ ;; Safeguard against either of the functions changing pt.
+ (goto-char p)
+ ;; Rewind list to look for another format
+ (setq try format-alist))
+ (setq try (cdr try))))))
+ ;; Deal with given format(s)
+ (or (listp format) (setq format (list format)))
+ (let ((do format) f)
+ (while do
+ (or (setq f (assq (car do) format-alist))
+ (error "Unknown format" (car do)))
+ ;; Decode:
+ (if (nth 3 f)
+ (setq end (format-decode-run-method (nth 3 f) begin end)))
+ ;; Call visit function if required
+ (if (and visit-flag (nth 6 f)) (funcall (nth 6 f) 1))
+ (setq do (cdr do)))))
+ (if visit-flag
+ (setq buffer-file-format format))
+ (set-buffer-modified-p mod)
+ ;; Return new length of region
+ (- end begin)))
+
+;;;
+;;; Interactive functions & entry points
+;;;
+
+(defun format-decode-buffer (&optional format)
+ "Translate the buffer from some FORMAT.
+If the format is not specified, this function attempts to guess.
+`buffer-file-format' is set to the format used, and any mode-functions
+for the format are called."
+ (interactive
+ (list (format-read "Translate buffer from format (default: guess): ")))
+ (save-excursion
+ (goto-char (point-min))
+ (format-decode format (buffer-size) t)))
+
+(defun format-decode-region (from to &optional format)
+ "Decode the region from some format.
+Arg FORMAT is optional; if omitted the format will be determined by looking
+for identifying regular expressions at the beginning of the region."
+ (interactive
+ (list (region-beginning) (region-end)
+ (format-read "Translate region from format (default: guess): ")))
+ (save-excursion
+ (goto-char from)
+ (format-decode format (- to from) nil)))
+
+(defun format-encode-buffer (&optional format)
+ "Translate the buffer into FORMAT.
+FORMAT defaults to `buffer-file-format'. It is a symbol naming one of the
+formats defined in `format-alist', or a list of such symbols."
+ (interactive
+ (list (format-read (format "Translate buffer to format (default %s): "
+ buffer-file-format))))
+ (format-encode-region (point-min) (point-max) format))
+
+(defun format-encode-region (start end &optional format)
+ "Translate the region into some FORMAT.
+FORMAT defaults to `buffer-file-format', it is a symbol naming
+one of the formats defined in `format-alist', or a list of such symbols."
+ (interactive
+ (list (region-beginning) (region-end)
+ (format-read (format "Translate region to format (default %s): "
+ buffer-file-format))))
+ (if (null format) (setq format buffer-file-format))
+ (if (symbolp format) (setq format (list format)))
+ (save-excursion
+ (goto-char end)
+ (let ( ; (cur-buf (current-buffer))
+ (end (point-marker)))
+ (while format
+ (let* ((info (assq (car format) format-alist))
+ (to-fn (nth 4 info))
+ (modify (nth 5 info))
+ ;; result
+ )
+ (if to-fn
+ (if modify
+ (setq end (format-encode-run-method to-fn start end
+ (current-buffer)))
+ (format-insert-annotations
+ (funcall to-fn start end (current-buffer)))))
+ (setq format (cdr format)))))))
+
+(defun format-write-file (filename format)
+ "Write current buffer into a FILE using some FORMAT.
+Makes buffer visit that file and sets the format as the default for future
+saves. If the buffer is already visiting a file, you can specify a directory
+name as FILE, to write a file of the same old name in that directory."
+ (interactive
+ ;; Same interactive spec as write-file, plus format question.
+ (let* ((file (if buffer-file-name
+ (read-file-name "Write file: "
+ nil nil nil nil)
+ (read-file-name "Write file: "
+ (cdr (assq 'default-directory
+ (buffer-local-variables)))
+ nil nil (buffer-name))))
+ (fmt (format-read (format "Write file `%s' in format: "
+ (file-name-nondirectory file)))))
+ (list file fmt)))
+ (setq buffer-file-format format)
+ (write-file filename))
+
+(defun format-find-file (filename format)
+ "Find the file FILE using data format FORMAT.
+If FORMAT is nil then do not do any format conversion."
+ (interactive
+ ;; Same interactive spec as write-file, plus format question.
+ (let* ((file (read-file-name "Find file: "))
+ (fmt (format-read (format "Read file `%s' in format: "
+ (file-name-nondirectory file)))))
+ (list file fmt)))
+ (let ((format-alist nil))
+ (find-file filename))
+ (if format
+ (format-decode-buffer format)))
+
+(defun format-insert-file (filename format &optional start end)
+ "Insert the contents of file FILE using data format FORMAT.
+If FORMAT is nil then do not do any format conversion.
+The optional third and fourth arguments START and END specify
+the part of the file to read.
+
+The return value is like the value of `insert-file-contents':
+a list (ABSOLUTE-FILE-NAME . SIZE)."
+ (interactive
+ ;; Same interactive spec as write-file, plus format question.
+ (let* ((file (read-file-name "Find file: "))
+ (fmt (format-read (format "Read file `%s' in format: "
+ (file-name-nondirectory file)))))
+ (list file fmt)))
+ (let (value size)
+ (let ((format-alist nil))
+ (setq value (insert-file-contents filename nil start end))
+ (setq size (nth 1 value)))
+ (if format
+ (setq size (format-decode format size)
+ value (cons (car value) size)))
+ value))
+
+(defun format-read (&optional prompt)
+ "Read and return the name of a format.
+Return value is a list, like `buffer-file-format'; it may be nil.
+Formats are defined in `format-alist'. Optional arg is the PROMPT to use."
+ (let* ((table (mapcar (lambda (x) (list (symbol-name (car x))))
+ format-alist))
+ (ans (completing-read (or prompt "Format: ") table nil t)))
+ (if (not (equal "" ans)) (list (intern ans)))))
+
+
+;;;
+;;; Below are some functions that may be useful in writing encoding and
+;;; decoding functions for use in format-alist.
+;;;
+
+(defun format-replace-strings (alist &optional reverse start end)
+ "Do multiple replacements on the buffer.
+ALIST is a list of (from . to) pairs, which should be proper arguments to
+`search-forward' and `replace-match' respectively.
+Optional 2nd arg REVERSE, if non-nil, means the pairs are (to . from), so that
+you can use the same list in both directions if it contains only literal
+strings.
+Optional args BEGIN and END specify a region of the buffer to operate on."
+ (save-excursion
+ (save-restriction
+ (or start (setq start (point-min)))
+ (if end (narrow-to-region (point-min) end))
+ (while alist
+ (let ((from (if reverse (cdr (car alist)) (car (car alist))))
+ (to (if reverse (car (cdr alist)) (cdr (car alist)))))
+ (goto-char start)
+ (while (search-forward from nil t)
+ (goto-char (match-beginning 0))
+ (insert to)
+ (set-text-properties (- (point) (length to)) (point)
+ (text-properties-at (point)))
+ (delete-region (point) (+ (point) (- (match-end 0)
+ (match-beginning 0)))))
+ (setq alist (cdr alist)))))))
+
+;;; Some list-manipulation functions that we need.
+
+(defun format-delq-cons (cons list)
+ "Remove the given CONS from LIST by side effect,
+and return the new LIST. Since CONS could be the first element
+of LIST, write `\(setq foo \(format-delq-cons element foo))' to be sure of
+changing the value of `foo'."
+ (if (eq cons list)
+ (cdr list)
+ (let ((p list))
+ (while (not (eq (cdr p) cons))
+ (if (null p) (error "format-delq-cons: not an element."))
+ (setq p (cdr p)))
+ ;; Now (cdr p) is the cons to delete
+ (setcdr p (cdr cons))
+ list)))
+
+(defun format-make-relatively-unique (a b)
+ "Delete common elements of lists A and B, return as pair.
+Compares using `equal'."
+ (let* ((acopy (copy-sequence a))
+ (bcopy (copy-sequence b))
+ (tail acopy))
+ (while tail
+ (let ((dup (member (car tail) bcopy))
+ (next (cdr tail)))
+ (if dup (setq acopy (format-delq-cons tail acopy)
+ bcopy (format-delq-cons dup bcopy)))
+ (setq tail next)))
+ (cons acopy bcopy)))
+
+(defun format-common-tail (a b)
+ "Given two lists that have a common tail, return it.
+Compares with `equal', and returns the part of A that is equal to the
+equivalent part of B. If even the last items of the two are not equal,
+returns nil."
+ (let ((la (length a))
+ (lb (length b)))
+ ;; Make sure they are the same length
+ (if (> la lb)
+ (setq a (nthcdr (- la lb) a))
+ (setq b (nthcdr (- lb la) b))))
+ (while (not (equal a b))
+ (setq a (cdr a)
+ b (cdr b)))
+ a)
+
+(defun format-reorder (items order)
+ "Arrange ITEMS to following partial ORDER.
+Elements of ITEMS equal to elements of ORDER will be rearranged to follow the
+ORDER. Unmatched items will go last."
+ (if order
+ (let ((item (member (car order) items)))
+ (if item
+ (cons (car item)
+ (format-reorder (format-delq-cons item items)
+ (cdr order)))
+ (format-reorder items (cdr order))))
+ items))
+
+(put 'face 'format-list-valued t) ; These text-properties take values
+(put 'unknown 'format-list-valued t) ; that are lists, the elements of which
+ ; should be considered separately.
+ ; See format-deannotate-region and
+ ; format-annotate-region.
+
+;;;
+;;; Decoding
+;;;
+
+(defun format-deannotate-region (from to translations next-fn)
+ "Translate annotations in the region into text properties.
+This sets text properties between FROM to TO as directed by the
+TRANSLATIONS and NEXT-FN arguments.
+
+NEXT-FN is a function that searches forward from point for an annotation.
+It should return a list of 4 elements: \(BEGIN END NAME POSITIVE). BEGIN and
+END are buffer positions bounding the annotation, NAME is the name searched
+for in TRANSLATIONS, and POSITIVE should be non-nil if this annotation marks
+the beginning of a region with some property, or nil if it ends the region.
+NEXT-FN should return nil if there are no annotations after point.
+
+The basic format of the TRANSLATIONS argument is described in the
+documentation for the `format-annotate-region' function. There are some
+additional things to keep in mind for decoding, though:
+
+When an annotation is found, the TRANSLATIONS list is searched for a
+text-property name and value that corresponds to that annotation. If the
+text-property has several annotations associated with it, it will be used only
+if the other annotations are also in effect at that point. The first match
+found whose annotations are all present is used.
+
+The text property thus determined is set to the value over the region between
+the opening and closing annotations. However, if the text-property name has a
+non-nil `format-list-valued' property, then the value will be consed onto the
+surrounding value of the property, rather than replacing that value.
+
+There are some special symbols that can be used in the \"property\" slot of
+the TRANSLATIONS list: PARAMETER and FUNCTION \(spelled in uppercase).
+Annotations listed under the pseudo-property PARAMETER are considered to be
+arguments of the immediately surrounding annotation; the text between the
+opening and closing parameter annotations is deleted from the buffer but saved
+as a string. The surrounding annotation should be listed under the
+pseudo-property FUNCTION. Instead of inserting a text-property for this
+annotation, the function listed in the VALUE slot is called to make whatever
+changes are appropriate. The function's first two arguments are the START and
+END locations, and the rest of the arguments are any PARAMETERs found in that
+region.
+
+Any annotations that are found by NEXT-FN but not defined by TRANSLATIONS
+are saved as values of the `unknown' text-property \(which is list-valued).
+The TRANSLATIONS list should usually contain an entry of the form
+ \(unknown \(nil format-annotate-value))
+to write these unknown annotations back into the file."
+ (save-excursion
+ (save-restriction
+ (narrow-to-region (point-min) to)
+ (goto-char from)
+ (let (next open-ans todo
+ ;; loc
+ unknown-ans)
+ (while (setq next (funcall next-fn))
+ (let* ((loc (nth 0 next))
+ (end (nth 1 next))
+ (name (nth 2 next))
+ (positive (nth 3 next))
+ (found nil))
+
+ ;; Delete the annotation
+ (delete-region loc end)
+ (cond
+ ;; Positive annotations are stacked, remembering location
+ (positive (setq open-ans (cons `(,name ((,loc . nil))) open-ans)))
+ ;; It is a negative annotation:
+ ;; Close the top annotation & add its text property.
+ ;; If the file's nesting is messed up, the close might not match
+ ;; the top thing on the open-annotations stack.
+ ;; If no matching annotation is open, just ignore the close.
+ ((not (assoc name open-ans))
+ (message "Extra closing annotation (%s) in file" name))
+ ;; If one is open, but not on the top of the stack, close
+ ;; the things in between as well. Set `found' when the real
+ ;; one is closed.
+ (t
+ (while (not found)
+ (let* ((top (car open-ans)) ; first on stack: should match.
+ (top-name (car top)) ; text property name
+ (top-extents (nth 1 top)) ; property regions
+ (params (cdr (cdr top))) ; parameters
+ (aalist translations)
+ (matched nil))
+ (if (equal name top-name)
+ (setq found t)
+ (message "Improper nesting in file."))
+ ;; Look through property names in TRANSLATIONS
+ (while aalist
+ (let ((prop (car (car aalist)))
+ (alist (cdr (car aalist))))
+ ;; And look through values for each property
+ (while alist
+ (let ((value (car (car alist)))
+ (ans (cdr (car alist))))
+ (if (member top-name ans)
+ ;; This annotation is listed, but still have to
+ ;; check if multiple annotations are satisfied
+ (if (member nil (mapcar (lambda (r)
+ (assoc r open-ans))
+ ans))
+ nil ; multiple ans not satisfied
+ ;; If there are multiple annotations going
+ ;; into one text property, split up the other
+ ;; annotations so they apply individually to
+ ;; the other regions.
+ (setcdr (car top-extents) loc)
+ (let ((to-split ans) this-one extents)
+ (while to-split
+ (setq this-one
+ (assoc (car to-split) open-ans)
+ extents (nth 1 this-one))
+ (if (not (eq this-one top))
+ (setcar (cdr this-one)
+ (format-subtract-regions
+ extents top-extents)))
+ (setq to-split (cdr to-split))))
+ ;; Set loop variables to nil so loop
+ ;; will exit.
+ (setq alist nil aalist nil matched t
+ ;; pop annotation off stack.
+ open-ans (cdr open-ans))
+ (let ((extents top-extents)
+ (start (car (car top-extents)))
+ (loc (cdr (car top-extents))))
+ (while extents
+ (cond
+ ;; Check for pseudo-properties
+ ((eq prop 'PARAMETER)
+ ;; A parameter of the top open ann:
+ ;; delete text and use as arg.
+ (if open-ans
+ ;; (If nothing open, discard).
+ (setq open-ans
+ (cons
+ (append (car open-ans)
+ (list
+ (buffer-substring
+ start loc)))
+ (cdr open-ans))))
+ (delete-region start loc))
+ ((eq prop 'FUNCTION)
+ ;; Not a property, but a function.
+ (let ((rtn
+ (apply value start loc params)))
+ (if rtn (setq todo (cons rtn todo)))))
+ (t
+ ;; Normal property/value pair
+ (setq todo
+ (cons (list start loc prop value)
+ todo))))
+ (setq extents (cdr extents)
+ start (car (car extents))
+ loc (cdr (car extents))))))))
+ (setq alist (cdr alist))))
+ (setq aalist (cdr aalist)))
+ (unless matched
+ ;; Didn't find any match for the annotation:
+ ;; Store as value of text-property `unknown'.
+ (setcdr (car top-extents) loc)
+ (let ((extents top-extents)
+ (start (car (car top-extents)))
+ (loc (cdr (car top-extents))))
+ (while extents
+ (setq open-ans (cdr open-ans)
+ todo (cons (list start loc 'unknown top-name)
+ todo)
+ unknown-ans (cons name unknown-ans)
+ extents (cdr extents)
+ start (car (car extents))
+ loc (cdr (car extents))))))))))))
+
+ ;; Once entire file has been scanned, add the properties.
+ (while todo
+ (let* ((item (car todo))
+ (from (nth 0 item))
+ (to (nth 1 item))
+ (prop (nth 2 item))
+ (val (nth 3 item)))
+
+ (if (numberp val) ; add to ambient value if numeric
+ (format-property-increment-region from to prop val 0)
+ (put-text-property
+ from to prop
+ (cond ((get prop 'format-list-valued) ; value gets consed onto
+ ; list-valued properties
+ (let ((prev (get-text-property from prop)))
+ (cons val (if (listp prev) prev (list prev)))))
+ (t val))))) ; normally, just set to val.
+ (setq todo (cdr todo)))
+
+ (if unknown-ans
+ (message "Unknown annotations: %s" unknown-ans))))))
+
+(defun format-subtract-regions (minu subtra)
+ "Remove the regions in SUBTRAHEND from the regions in MINUEND. A region
+is a dotted pair (from . to). Both parameters are lists of regions. Each
+list must contain nonoverlapping, noncontiguous regions, in descending
+order. The result is also nonoverlapping, noncontiguous, and in descending
+order. The first element of MINUEND can have a cdr of nil, indicating that
+the end of that region is not yet known."
+ (let* ((minuend (copy-alist minu))
+ (subtrahend (copy-alist subtra))
+ (m (car minuend))
+ (s (car subtrahend))
+ results)
+ (while (and minuend subtrahend)
+ (cond
+ ;; The minuend starts after the subtrahend ends; keep it.
+ ((> (car m) (cdr s))
+ (setq results (cons m results)
+ minuend (cdr minuend)
+ m (car minuend)))
+ ;; The minuend extends beyond the end of the subtrahend. Chop it off.
+ ((or (null (cdr m)) (> (cdr m) (cdr s)))
+ (setq results (cons (cons (1+ (cdr s)) (cdr m)) results))
+ (setcdr m (cdr s)))
+ ;; The subtrahend starts after the minuend ends; throw it away.
+ ((< (cdr m) (car s))
+ (setq subtrahend (cdr subtrahend) s (car subtrahend)))
+ ;; The subtrahend extends beyond the end of the minuend. Chop it off.
+ (t ;(<= (cdr m) (cdr s)))
+ (if (>= (car m) (car s))
+ (setq minuend (cdr minuend) m (car minuend))
+ (setcdr m (1- (car s)))
+ (setq subtrahend (cdr subtrahend) s (car subtrahend))))))
+ (nconc (nreverse results) minuend)))
+
+;; This should probably go somewhere other than format.el. Then again,
+;; indent.el has alter-text-property. NOTE: We can also use
+;; next-single-property-change instead of text-property-not-all, but then
+;; we have to see if we passed TO.
+(defun format-property-increment-region (from to prop delta default)
+ "Increment property PROP over the region between FROM and TO by the
+amount DELTA (which may be negative). If property PROP is nil anywhere
+in the region, it is treated as though it were DEFAULT."
+ (let ((cur from) val newval next)
+ (while cur
+ (setq val (get-text-property cur prop)
+ newval (+ (or val default) delta)
+ next (text-property-not-all cur to prop val))
+ (put-text-property cur (or next to) prop newval)
+ (setq cur next))))
+
+;;;
+;;; Encoding
+;;;
+
+(defun format-insert-annotations (list &optional offset)
+ "Apply list of annotations to buffer as `write-region' would.
+Inserts each element of the given LIST of buffer annotations at its
+appropriate place. Use second arg OFFSET if the annotations' locations are
+not relative to the beginning of the buffer: annotations will be inserted
+at their location-OFFSET+1 \(ie, the offset is treated as the character number
+of the first character in the buffer)."
+ (if (not offset)
+ (setq offset 0)
+ (setq offset (1- offset)))
+ (let ((l (reverse list)))
+ (while l
+ (goto-char (- (car (car l)) offset))
+ (insert (cdr (car l)))
+ (setq l (cdr l)))))
+
+(defun format-annotate-value (old new)
+ "Return OLD and NEW as a \(close . open) annotation pair.
+Useful as a default function for TRANSLATIONS alist when the value of the text
+property is the name of the annotation that you want to use, as it is for the
+`unknown' text property."
+ (cons (if old (list old))
+ (if new (list new))))
+
+(defun format-annotate-region (from to trans format-fn ignore)
+ "Generate annotations for text properties in the region.
+Searches for changes between FROM and TO, and describes them with a list of
+annotations as defined by alist TRANSLATIONS and FORMAT-FN. IGNORE lists text
+properties not to consider; any text properties that are neither ignored nor
+listed in TRANSLATIONS are warned about.
+If you actually want to modify the region, give the return value of this
+function to `format-insert-annotations'.
+
+Format of the TRANSLATIONS argument:
+
+Each element is a list whose car is a PROPERTY, and the following
+elements are VALUES of that property followed by the names of zero or more
+ANNOTATIONS. Whenever the property takes on that value, the annotations
+\(as formatted by FORMAT-FN) are inserted into the file.
+When the property stops having that value, the matching negated annotation
+will be inserted \(it may actually be closed earlier and reopened, if
+necessary, to keep proper nesting).
+
+If the property's value is a list, then each element of the list is dealt with
+separately.
+
+If a VALUE is numeric, then it is assumed that there is a single annotation
+and each occurrence of it increments the value of the property by that number.
+Thus, given the entry \(left-margin \(4 \"indent\")), if the left margin
+changes from 4 to 12, two <indent> annotations will be generated.
+
+If the VALUE is nil, then instead of annotations, a function should be
+specified. This function is used as a default: it is called for all
+transitions not explicitly listed in the table. The function is called with
+two arguments, the OLD and NEW values of the property. It should return
+lists of annotations like `format-annotate-location' does.
+
+ The same structure can be used in reverse for reading files."
+ (let ((all-ans nil) ; All annotations - becomes return value
+ (open-ans nil) ; Annotations not yet closed
+ (loc nil) ; Current location
+ (not-found nil)) ; Properties that couldn't be saved
+ (while (or (null loc)
+ (and (setq loc (next-property-change loc nil to))
+ (< loc to)))
+ (or loc (setq loc from))
+ (let* ((ans (format-annotate-location loc (= loc from) ignore trans))
+ (neg-ans (format-reorder (aref ans 0) open-ans))
+ (pos-ans (aref ans 1))
+ (ignored (aref ans 2)))
+ (setq not-found (append ignored not-found)
+ ignore (append ignored ignore))
+ ;; First do the negative (closing) annotations
+ (while neg-ans
+ ;; Check if it's missing. This can happen (eg, a numeric property
+ ;; going negative can generate closing annotations before there are
+ ;; any open). Warn user & ignore.
+ (if (not (member (car neg-ans) open-ans))
+ (message "Can't close %s: not open." (car neg-ans))
+ (while (not (equal (car neg-ans) (car open-ans)))
+ ;; To close anno. N, need to first close ans 1 to N-1,
+ ;; remembering to re-open them later.
+ (setq pos-ans (cons (car open-ans) pos-ans))
+ (setq all-ans
+ (cons (cons loc (funcall format-fn (car open-ans) nil))
+ all-ans))
+ (setq open-ans (cdr open-ans)))
+ ;; Now remove the one we're really interested in from open list.
+ (setq open-ans (cdr open-ans))
+ ;; And put the closing annotation here.
+ (setq all-ans
+ (cons (cons loc (funcall format-fn (car neg-ans) nil))
+ all-ans)))
+ (setq neg-ans (cdr neg-ans)))
+ ;; Now deal with positive (opening) annotations
+ (let ( ; (p pos-ans)
+ )
+ (while pos-ans
+ (setq open-ans (cons (car pos-ans) open-ans))
+ (setq all-ans
+ (cons (cons loc (funcall format-fn (car pos-ans) t))
+ all-ans))
+ (setq pos-ans (cdr pos-ans))))))
+
+ ;; Close any annotations still open
+ (while open-ans
+ (setq all-ans
+ (cons (cons to (funcall format-fn (car open-ans) nil))
+ all-ans))
+ (setq open-ans (cdr open-ans)))
+ (if not-found
+ (message "These text properties could not be saved:\n %s"
+ not-found))
+ (nreverse all-ans)))
+
+;;; Internal functions for format-annotate-region.
+
+(defun format-annotate-location (loc all ignore trans)
+ "Return annotation(s) needed at LOCATION.
+This includes any properties that change between LOC-1 and LOC.
+If ALL is true, don't look at previous location, but generate annotations for
+all non-nil properties.
+Third argument IGNORE is a list of text-properties not to consider.
+
+Return value is a vector of 3 elements:
+1. List of names of the annotations to close
+2. List of the names of annotations to open.
+3. List of properties that were ignored or couldn't be annotated."
+ (let* ((prev-loc (1- loc))
+ (before-plist (if all nil (text-properties-at prev-loc)))
+ (after-plist (text-properties-at loc))
+ p negatives positives prop props not-found)
+ ;; make list of all property names involved
+ (setq p before-plist)
+ (while p
+ (if (not (memq (car p) props))
+ (setq props (cons (car p) props)))
+ (setq p (cdr (cdr p))))
+ (setq p after-plist)
+ (while p
+ (if (not (memq (car p) props))
+ (setq props (cons (car p) props)))
+ (setq p (cdr (cdr p))))
+
+ (while props
+ (setq prop (car props)
+ props (cdr props))
+ (if (memq prop ignore)
+ nil ; If it's been ignored before, ignore it now.
+ (let ((before (if all nil (car (cdr (memq prop before-plist)))))
+ (after (car (cdr (memq prop after-plist)))))
+ (if (equal before after)
+ nil ; no change; ignore
+ (let ((result (format-annotate-single-property-change
+ prop before after trans)))
+ (if (not result)
+ (setq not-found (cons prop not-found))
+ (setq negatives (nconc negatives (car result))
+ positives (nconc positives (cdr result)))))))))
+ (vector negatives positives not-found)))
+
+(defun format-annotate-single-property-change (prop old new trans)
+ "Return annotations for PROPERTY changing from OLD to NEW.
+These are searched for in the TRANSLATIONS alist.
+If NEW does not appear in the list, but there is a default function, then that
+function is called.
+Annotations to open and to close are returned as a dotted pair."
+ (let ((prop-alist (cdr (assoc prop trans)))
+ ;; default
+ )
+ (if (not prop-alist)
+ nil
+ ;; If either old or new is a list, have to treat both that way.
+ (if (or (consp old) (consp new))
+ (let* ((old (if (listp old) old (list old)))
+ (new (if (listp new) new (list new)))
+ ;; (tail (format-common-tail old new))
+ close open)
+ (while old
+ (setq close
+ (append (car (format-annotate-atomic-property-change
+ prop-alist (car old) nil))
+ close)
+ old (cdr old)))
+ (while new
+ (setq open
+ (append (cdr (format-annotate-atomic-property-change
+ prop-alist nil (car new)))
+ open)
+ new (cdr new)))
+ (format-make-relatively-unique close open))
+ (format-annotate-atomic-property-change prop-alist old new)))))
+
+(defun format-annotate-atomic-property-change (prop-alist old new)
+ "Internal function annotate a single property change.
+PROP-ALIST is the relevant segment of a TRANSLATIONS list.
+OLD and NEW are the values."
+ (let (num-ann)
+ ;; If old and new values are numbers,
+ ;; look for a number in PROP-ALIST.
+ (if (and (or (null old) (numberp old))
+ (or (null new) (numberp new)))
+ (progn
+ (setq num-ann prop-alist)
+ (while (and num-ann (not (numberp (car (car num-ann)))))
+ (setq num-ann (cdr num-ann)))))
+ (if num-ann
+ ;; Numerical annotation - use difference
+ (progn
+ ;; If property is numeric, nil means 0
+ (cond ((and (numberp old) (null new))
+ (setq new 0))
+ ((and (numberp new) (null old))
+ (setq old 0)))
+
+ (let* ((entry (car num-ann))
+ (increment (car entry))
+ (n (ceiling (/ (float (- new old)) (float increment))))
+ (anno (car (cdr entry))))
+ (if (> n 0)
+ (cons nil (make-list n anno))
+ (cons (make-list (- n) anno) nil))))
+
+ ;; Standard annotation
+ (let ((close (and old (cdr (assoc old prop-alist))))
+ (open (and new (cdr (assoc new prop-alist)))))
+ (if (or close open)
+ (format-make-relatively-unique close open)
+ ;; Call "Default" function, if any
+ (let ((default (assq nil prop-alist)))
+ (if default
+ (funcall (car (cdr default)) old new))))))))
+
+;;; format.el ends here
projects / chise / xemacs-chise.git- / blobdiff