code.delx.au - gnu-emacs/blob - lisp/progmodes/cpp.el

   1 ;;; cpp.el --- highlight or hide text according to cpp conditionals
   2
   3 ;; Copyright (C) 1994-1995, 2001-2015 Free Software Foundation, Inc.
   4
   5 ;; Author: Per Abrahamsen <abraham@dina.kvl.dk>
   6 ;; Keywords: c, faces, tools
   7
   8 ;; This file is part of GNU Emacs.
   9
  10 ;; GNU Emacs is free software: you can redistribute it and/or modify
  11 ;; it under the terms of the GNU General Public License as published by
  12 ;; the Free Software Foundation, either version 3 of the License, or
  13 ;; (at your option) any later version.
  14
  15 ;; GNU Emacs is distributed in the hope that it will be useful,
  16 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 ;; GNU General Public License for more details.
  19
  20 ;; You should have received a copy of the GNU General Public License
  21 ;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
  22
  23 ;;; Commentary:
  24
  25 ;; Parse a text for C preprocessor conditionals, and highlight or hide
  26 ;; the text inside the conditionals as you wish.
  27
  28 ;; This package is inspired by Jim Coplien's delta editor for SCCS.
  29
  30 ;;; Todo:
  31
  32 ;; Should parse "#if" and "#elif" expressions and merge the faces
  33 ;; somehow.
  34
  35 ;; Somehow it is sometimes possible to make changes near a read only
  36 ;; area which you can't undo.  Their are other strange effects in that
  37 ;; area.
  38
  39 ;; The Edit buffer should -- optionally -- appear in its own frame.
  40
  41 ;; Conditionals seem to be rear-sticky.  They shouldn't be.
  42
  43 ;; Restore window configurations when exiting CPP Edit buffer.
  44
  45 ;;; Code:
  46
  47 ;;; Customization:
  48 (defgroup cpp nil
  49   "Highlight or hide text according to cpp conditionals."
  50   :link '(custom-group-link :tag "Font Lock Faces group" font-lock-faces)
  51   :group 'c
  52   :prefix "cpp-")
  53
  54 (defcustom cpp-config-file (convert-standard-filename ".cpp.el")
  55   "File name to save cpp configuration."
  56   :type 'file
  57   :group 'cpp)
  58
  59 (define-widget 'cpp-face 'lazy
  60   "Either a face or the special symbol `invisible'."
  61   :type '(choice (const invisible) (face)))
  62
  63 (defcustom cpp-known-face 'invisible
  64   "Face used for known cpp symbols."
  65   :type 'cpp-face
  66   :group 'cpp)
  67
  68 (defcustom cpp-unknown-face 'highlight
  69   "Face used for unknown cpp symbols."
  70   :type 'cpp-face
  71   :group 'cpp)
  72
  73 (defcustom cpp-face-type 'light
  74   "Indicate what background face type you prefer.
  75 Can be either light or dark for color screens, mono for monochrome
  76 screens, and none if you don't use a window system and don't have
  77 a color-capable display."
  78   :options '(light dark mono nil)
  79   :type 'symbol
  80   :group 'cpp)
  81
  82 (defcustom cpp-known-writable t
  83   "Non-nil means you are allowed to modify the known conditionals."
  84   :type 'boolean
  85   :group 'cpp)
  86
  87 (defcustom cpp-unknown-writable t
  88   "Non-nil means you are allowed to modify the unknown conditionals."
  89   :type 'boolean
  90   :group 'cpp)
  91
  92 (defcustom cpp-edit-list nil
  93   "Alist of cpp macros and information about how they should be displayed.
  94 Each entry is a list with the following elements:
  95 0. The name of the macro (a string).
  96 1. Face used for text that is `ifdef' the macro.
  97 2. Face used for text that is `ifndef' the macro.
  98 3. t, nil, or `both' depending on what text may be edited."
  99   :type '(repeat (list (string :tag "Macro")
 100                        (cpp-face :tag "True")
 101                        (cpp-face :tag "False")
 102                        (choice (const :tag "True branch writable" t)
 103                                (const :tag "False branch writable" nil)
 104                                (const :tag "Both branches writable" both))))
 105   :group 'cpp)
 106
 107 (defvar cpp-overlay-list nil)
 108 ;; List of cpp overlays active in the current buffer.
 109 (make-variable-buffer-local 'cpp-overlay-list)
 110
 111 (defvar cpp-callback-data)
 112 (defvar cpp-state-stack)
 113
 114 (defconst cpp-face-type-list
 115   '(("light color background" . light)
 116     ("dark color background" . dark)
 117     ("monochrome" . mono)
 118     ("tty" . none))
 119   "Alist of strings and names of the defined face collections.")
 120
 121 (defconst cpp-writable-list
 122   ;; Names used for the writable property.
 123   '(("writable" . t)
 124     ("read-only" . nil)))
 125
 126 (defvar cpp-button-event nil)
 127 ;; This will be t in the callback for `cpp-make-button'.
 128
 129 (defvar cpp-edit-buffer nil)
 130 ;; Real buffer whose cpp display information we are editing.
 131 (make-variable-buffer-local 'cpp-edit-buffer)
 132
 133 (defconst cpp-branch-list
 134   ;; Alist of branches.
 135   '(("false" . nil)
 136     ("true" . t)
 137     ("both" . both)))
 138
 139 ;; FIXME Gets clobbered by cpp-choose-face, so why is even it a defcustom?
 140 (defcustom cpp-face-default-list nil
 141   "Alist of faces you can choose from for cpp conditionals.
 142 Each element has the form (STRING . FACE), where STRING
 143 serves as a name (for `cpp-highlight-buffer' only)
 144 and FACE is either a face (a symbol)
 145 or a cons cell (background-color . COLOR)."
 146   :type '(alist :key-type (string :tag "Name")
 147                 :value-type (choice face
 148                                     (const invisible)
 149                                     (cons (const background-color)
 150                                           (string :tag "Color"))))
 151   :group 'cpp)
 152
 153 (defcustom cpp-face-light-name-list
 154   '("light gray" "light blue" "light cyan" "light yellow" "light pink"
 155     "pale green" "beige" "orange" "magenta" "violet" "medium purple"
 156     "turquoise")
 157   "Background colors useful with dark foreground colors."
 158   :type '(repeat string)
 159   :group 'cpp)
 160
 161 (defcustom cpp-face-dark-name-list
 162   '("dim gray" "blue" "cyan" "yellow" "red"
 163     "dark green" "brown" "dark orange" "dark khaki" "dark violet" "purple"
 164     "dark turquoise")
 165   "Background colors useful with light foreground colors."
 166   :type '(repeat string)
 167   :group 'cpp)
 168
 169 (defcustom cpp-face-light-list nil
 170   "Alist of names and faces to be used for light backgrounds."
 171   :type '(repeat (cons string (choice face
 172                                       (cons (const background-color) string))))
 173   :group 'cpp)
 174
 175 (defcustom cpp-face-dark-list nil
 176   "Alist of names and faces to be used for dark backgrounds."
 177   :type '(repeat (cons string (choice face
 178                                       (cons (const background-color) string))))
 179   :group 'cpp)
 180
 181 (defcustom cpp-face-mono-list
 182   '(("bold" . bold)
 183     ("bold-italic" . bold-italic)
 184     ("italic" . italic)
 185     ("underline" . underline))
 186   "Alist of names and faces to be used for monochrome screens."
 187   :type '(repeat (cons string face))
 188   :group 'cpp)
 189
 190 (defcustom cpp-face-none-list
 191    '(("default" . default)
 192      ("invisible" . invisible))
 193    "Alist of names and faces available even if you don't use a window system."
 194   :type '(repeat (cons string cpp-face))
 195   :group 'cpp)
 196
 197 (defvar cpp-face-all-list
 198   (append cpp-face-light-list
 199           cpp-face-dark-list
 200           cpp-face-mono-list
 201           cpp-face-none-list)
 202   "All faces used for highlighting text inside cpp conditionals.")
 203
 204 ;;; Parse Buffer:
 205
 206 (defvar cpp-parse-symbols nil
 207   "List of cpp macros used in the local buffer.")
 208 (make-variable-buffer-local 'cpp-parse-symbols)
 209
 210 (defconst cpp-parse-regexp
 211   ;; Regexp matching all tokens needed to find conditionals.
 212   (concat
 213    "'\\|\"\\|/\\*\\|//\\|"
 214    "\\(^[ \t]*#[ \t]*\\(ifdef\\|ifndef\\|if\\|"
 215    "elif\\|else\\|endif\\)\\b\\)"))
 216
 217 ;;;###autoload
 218 (defun cpp-highlight-buffer (arg)
 219   "Highlight C code according to preprocessor conditionals.
 220 This command pops up a buffer which you should edit to specify
 221 what kind of highlighting to use, and the criteria for highlighting.
 222 A prefix arg suppresses display of that buffer."
 223   (interactive "P")
 224   (unless (or (eq t buffer-invisibility-spec)
 225               (memq 'cpp buffer-invisibility-spec))
 226     (add-to-invisibility-spec 'cpp))
 227   (setq cpp-parse-symbols nil)
 228   (cpp-parse-reset)
 229   (if (null cpp-edit-list)
 230       (cpp-edit-load))
 231   (let (cpp-state-stack)
 232     (save-excursion
 233       (goto-char (point-min))
 234       (cpp-progress-message "Parsing...")
 235       (while (re-search-forward cpp-parse-regexp nil t)
 236         (cpp-progress-message "Parsing...%d%%"
 237                               (floor (* 100.0 (- (point) (point-min)))
 238                                      (buffer-size)))
 239         (let ((match (buffer-substring (match-beginning 0) (match-end 0))))
 240           (cond ((or (string-equal match "'")
 241                      (string-equal match "\""))
 242                  (goto-char (match-beginning 0))
 243                  (condition-case nil
 244                      (forward-sexp)
 245                    (error (cpp-parse-error
 246                            "Unterminated string or character"))))
 247                 ((string-equal match "/*")
 248                  (or (search-forward "*/" nil t)
 249                      (error "Unterminated comment")))
 250                 ((string-equal match "//")
 251                  (skip-chars-forward "^\n\r"))
 252                 (t
 253                  (end-of-line 1)
 254                  (let ((from (match-beginning 1))
 255                        (to (1+ (point)))
 256                        (type (buffer-substring (match-beginning 2)
 257                                                (match-end 2)))
 258                        (expr (buffer-substring (match-end 1) (point))))
 259                    (cond ((string-equal type "ifdef")
 260                           (cpp-parse-open t expr from to))
 261                          ((string-equal type "ifndef")
 262                           (cpp-parse-open nil expr from to))
 263                          ((string-equal type "if")
 264                           (cpp-parse-open t expr from to))
 265                          ((string-equal type "elif")
 266                           (let (cpp-known-face cpp-unknown-face)
 267                             (cpp-parse-close from to))
 268                           (cpp-parse-open t expr from to))
 269                          ((string-equal type "else")
 270                           (or cpp-state-stack
 271                               (cpp-parse-error "Top level #else"))
 272                           (let ((entry (list (not (nth 0 (car cpp-state-stack)))
 273                                              (nth 1 (car cpp-state-stack))
 274                                              from to)))
 275                             (cpp-parse-close from to)
 276                             (setq cpp-state-stack (cons entry cpp-state-stack))))
 277                          ((string-equal type "endif")
 278                           (cpp-parse-close from to))
 279                          (t
 280                           (cpp-parse-error "Parser error"))))))))
 281       (message "Parsing...done"))
 282     (if cpp-state-stack
 283       (save-excursion
 284         (goto-char (nth 3 (car cpp-state-stack)))
 285         (cpp-parse-error "Unclosed conditional"))))
 286   (or arg
 287       (null cpp-parse-symbols)
 288       (cpp-parse-edit)))
 289
 290 (defun cpp-parse-open (branch expr begin end)
 291   "Push information about conditional-beginning onto `cpp-state-stack'."
 292   ;; Discard comments within this line.
 293   (while (string-match "\\b[ \t]*/\\*.*\\*/[ \t]*\\b" expr)
 294     (setq expr (concat (substring expr 0 (match-beginning 0))
 295                        (substring expr (match-end 0)))))
 296   ;; If a comment starts on this line and continues past, discard it.
 297   (if (string-match "\\b[ \t]*/\\*" expr)
 298       (setq expr (substring expr 0 (match-beginning 0))))
 299   ;; Delete any C++ comment from the line.
 300   (if (string-match "\\b[ \t]*\\(//.*\\)?$" expr)
 301       (setq expr (substring expr 0 (match-beginning 0))))
 302   (while (string-match "[ \t]+" expr)
 303       (setq expr (concat (substring expr 0 (match-beginning 0))
 304                          (substring expr (match-end 0)))))
 305   (setq cpp-state-stack (cons (list branch expr begin end) cpp-state-stack))
 306   (or (member expr cpp-parse-symbols)
 307       (setq cpp-parse-symbols
 308             (cons expr cpp-parse-symbols)))
 309   (if (assoc expr cpp-edit-list)
 310       (cpp-make-known-overlay begin end)
 311     (cpp-make-unknown-overlay begin end)))
 312
 313 (defun cpp-parse-close (from to)
 314   ;; Pop top of cpp-state-stack and create overlay.
 315   (let ((entry (assoc (nth 1 (car cpp-state-stack)) cpp-edit-list))
 316         (branch (nth 0 (car cpp-state-stack)))
 317         (end (nth 3 (car cpp-state-stack))))
 318     (setq cpp-state-stack (cdr cpp-state-stack))
 319     (if entry
 320         (let ((face (nth (if branch 1 2) entry))
 321               (read-only (eq (not branch) (nth 3 entry)))
 322               (priority (length cpp-state-stack))
 323               (overlay (make-overlay end from)))
 324           (cpp-make-known-overlay from to)
 325           (setq cpp-overlay-list (cons overlay cpp-overlay-list))
 326           (if priority (overlay-put overlay 'priority priority))
 327           (cond ((eq face 'invisible)
 328                  (cpp-make-overlay-hidden overlay))
 329                 ((eq face 'default))
 330                 (t
 331                  (overlay-put overlay 'face face)))
 332           (if read-only
 333               (cpp-make-overlay-read-only overlay)
 334             (cpp-make-overlay-sticky overlay)))
 335       (cpp-make-unknown-overlay from to))))
 336
 337 (defun cpp-parse-error (error)
 338   ;; Error message issued by the cpp parser.
 339   (error "%s at line %d" error (count-lines (point-min) (point))))
 340
 341 (defun cpp-parse-reset ()
 342   "Reset display of cpp conditionals to normal."
 343   (interactive)
 344   (while cpp-overlay-list
 345     (delete-overlay (car cpp-overlay-list))
 346     (setq cpp-overlay-list (cdr cpp-overlay-list))))
 347
 348 ;;;###autoload
 349 (defun cpp-parse-edit ()
 350   "Edit display information for cpp conditionals."
 351   (interactive)
 352   (or cpp-parse-symbols
 353       (cpp-highlight-buffer t))
 354   (let ((buffer (current-buffer)))
 355     (pop-to-buffer "*CPP Edit*")
 356     (cpp-edit-mode)
 357     (setq cpp-edit-buffer buffer)
 358     (cpp-edit-reset)))
 359
 360 ;;; Overlays:
 361
 362 (defun cpp-make-known-overlay (start end)
 363   ;; Create an overlay for a known cpp command from START to END.
 364   (let ((overlay (make-overlay start end)))
 365     (if (eq cpp-known-face 'invisible)
 366         (cpp-make-overlay-hidden overlay)
 367       (or (eq cpp-known-face 'default)
 368           (overlay-put overlay 'face cpp-known-face))
 369       (if cpp-known-writable
 370           ()
 371         (overlay-put overlay 'modification-hooks '(cpp-signal-read-only))
 372         (overlay-put overlay 'insert-in-front-hooks '(cpp-signal-read-only))))
 373     (setq cpp-overlay-list (cons overlay cpp-overlay-list))))
 374
 375 (defun cpp-make-unknown-overlay (start end)
 376   ;; Create an overlay for an unknown cpp command from START to END.
 377   (let ((overlay (make-overlay start end)))
 378     (cond ((eq cpp-unknown-face 'invisible)
 379            (cpp-make-overlay-hidden overlay))
 380           ((eq cpp-unknown-face 'default))
 381           (t
 382            (overlay-put overlay 'face cpp-unknown-face)))
 383     (if cpp-unknown-writable
 384         ()
 385       (overlay-put overlay 'modification-hooks '(cpp-signal-read-only))
 386       (overlay-put overlay 'insert-in-front-hooks '(cpp-signal-read-only)))
 387     (setq cpp-overlay-list (cons overlay cpp-overlay-list))))
 388
 389 (defun cpp-make-overlay-hidden (overlay)
 390   ;; Make overlay hidden and intangible.
 391   (overlay-put overlay 'invisible 'cpp)
 392   (overlay-put overlay 'modification-hooks '(cpp-signal-read-only))
 393   (overlay-put overlay 'insert-in-front-hooks '(cpp-signal-read-only)))
 394
 395 (defun cpp-make-overlay-read-only (overlay)
 396   ;; Make overlay read only.
 397   (overlay-put overlay 'modification-hooks '(cpp-signal-read-only))
 398   (overlay-put overlay 'insert-in-front-hooks '(cpp-signal-read-only))
 399   (overlay-put overlay 'insert-behind-hooks '(cpp-signal-read-only)))
 400
 401 (defun cpp-make-overlay-sticky (overlay)
 402   ;; Make OVERLAY grow when you insert text at either end.
 403   (overlay-put overlay 'insert-in-front-hooks '(cpp-grow-overlay))
 404   (overlay-put overlay 'insert-behind-hooks '(cpp-grow-overlay)))
 405
 406 (defun cpp-signal-read-only (overlay after start end &optional _len)
 407   ;; Only allow deleting the whole overlay.
 408   ;; Trying to change a read-only overlay.
 409   (if (and (not after)
 410            (or (< (overlay-start overlay) start)
 411                (> (overlay-end overlay) end)))
 412       (error "This text is read only")))
 413
 414 (defun cpp-grow-overlay (overlay after start end &optional _len)
 415   ;; Make OVERLAY grow to contain range START to END.
 416   (if after
 417       (move-overlay overlay
 418                     (min start (overlay-start overlay))
 419                     (max end (overlay-end overlay)))))
 420
 421 ;;; Edit Buffer:
 422
 423 (defvar cpp-edit-mode-map
 424   (let ((map (make-keymap)))
 425     (suppress-keymap map)
 426     (define-key map [ down-mouse-2 ] 'cpp-push-button)
 427     (define-key map [ mouse-2 ] 'ignore)
 428     (define-key map " " 'scroll-up-command)
 429     (define-key map [?\S-\ ] 'scroll-down-command)
 430     (define-key map "\C-?" 'scroll-down-command)
 431     (define-key map [ delete ] 'scroll-down)
 432     (define-key map "\C-c\C-c" 'cpp-edit-apply)
 433     (define-key map "a" 'cpp-edit-apply)
 434     (define-key map "A" 'cpp-edit-apply)
 435     (define-key map "r" 'cpp-edit-reset)
 436     (define-key map "R" 'cpp-edit-reset)
 437     (define-key map "s" 'cpp-edit-save)
 438     (define-key map "S" 'cpp-edit-save)
 439     (define-key map "l" 'cpp-edit-load)
 440     (define-key map "L" 'cpp-edit-load)
 441     (define-key map "h" 'cpp-edit-home)
 442     (define-key map "H" 'cpp-edit-home)
 443     (define-key map "b" 'cpp-edit-background)
 444     (define-key map "B" 'cpp-edit-background)
 445     (define-key map "k" 'cpp-edit-known)
 446     (define-key map "K" 'cpp-edit-known)
 447     (define-key map "u" 'cpp-edit-unknown)
 448     (define-key map "u" 'cpp-edit-unknown)
 449     (define-key map "t" 'cpp-edit-true)
 450     (define-key map "T" 'cpp-edit-true)
 451     (define-key map "f" 'cpp-edit-false)
 452     (define-key map "F" 'cpp-edit-false)
 453     (define-key map "w" 'cpp-edit-write)
 454     (define-key map "W" 'cpp-edit-write)
 455     (define-key map "X" 'cpp-edit-toggle-known)
 456     (define-key map "x" 'cpp-edit-toggle-known)
 457     (define-key map "Y" 'cpp-edit-toggle-unknown)
 458     (define-key map "y" 'cpp-edit-toggle-unknown)
 459     (define-key map "q" 'bury-buffer)
 460     (define-key map "Q" 'bury-buffer)
 461     map)
 462   "Keymap for `cpp-edit-mode'.")
 463
 464
 465
 466 (defvar cpp-edit-symbols nil)
 467 ;; Symbols defined in the edit buffer.
 468 (make-variable-buffer-local 'cpp-edit-symbols)
 469
 470 (define-derived-mode cpp-edit-mode fundamental-mode "CPP Edit"
 471   "Major mode for editing the criteria for highlighting cpp conditionals.
 472 Click on objects to change them.
 473 You can also use the keyboard accelerators indicated like this: [K]ey."
 474   (buffer-disable-undo)
 475   (auto-save-mode -1)
 476   (setq buffer-read-only t))
 477
 478 (defun cpp-edit-apply ()
 479   "Apply edited display information to original buffer."
 480   (interactive)
 481   (cpp-edit-home)
 482   (cpp-highlight-buffer t))
 483
 484 (defun cpp-edit-reset ()
 485   "Reset display information from original buffer."
 486   (interactive)
 487   (let ((buffer (current-buffer))
 488         (buffer-read-only nil)
 489         (start (window-start))
 490         (pos (point))
 491         symbols)
 492     (set-buffer cpp-edit-buffer)
 493     (setq symbols cpp-parse-symbols)
 494     (set-buffer buffer)
 495     (setq cpp-edit-symbols symbols)
 496     (erase-buffer)
 497     (insert "CPP Display Information for `")
 498     (cpp-make-button (buffer-name cpp-edit-buffer) 'cpp-edit-home)
 499     (insert "'\n\nClick mouse-2 on item you want to change or use\n"
 500             "or switch to this buffer and type the keyboard equivalents.\n"
 501             "Keyboard equivalents are indicated with brackets like [T]his.\n\n")
 502     (cpp-make-button "[H]ome (display the C file)" 'cpp-edit-home)
 503     (insert "  ")
 504     (cpp-make-button "[A]pply new settings" 'cpp-edit-apply)
 505     (insert "\n")
 506     (cpp-make-button "[S]ave settings" 'cpp-edit-save)
 507     (insert "  ")
 508     (cpp-make-button "[L]oad settings" 'cpp-edit-load)
 509     (insert "\n\n")
 510
 511     (insert "[B]ackground: ")
 512     (cpp-make-button (car (rassq cpp-face-type cpp-face-type-list))
 513                      'cpp-edit-background)
 514     (insert "\n[K]nown conditionals: ")
 515     (cpp-make-button (cpp-face-name cpp-known-face)
 516                      'cpp-edit-known nil t)
 517     (insert " [X] ")
 518     (cpp-make-button (car (rassq cpp-known-writable cpp-writable-list))
 519                      'cpp-edit-toggle-known)
 520     (insert "\n[U]nknown conditionals: ")
 521     (cpp-make-button (cpp-face-name cpp-unknown-face)
 522                      'cpp-edit-unknown nil t)
 523     (insert " [Y] ")
 524     (cpp-make-button (car (rassq cpp-unknown-writable cpp-writable-list))
 525                      'cpp-edit-toggle-unknown)
 526     (insert (format "\n\n\n%39s: %14s %14s %7s\n\n" "Expression"
 527                     "[T]rue Face" "[F]alse Face" "[W]rite"))
 528
 529     (setq symbols (reverse symbols))
 530     (while symbols
 531       (let*  ((symbol (car symbols))
 532               (entry (assoc symbol cpp-edit-list))
 533               (true (nth 1 entry))
 534               (false (nth 2 entry))
 535               (write (if entry (nth 3 entry) 'both)))
 536         (setq symbols (cdr symbols))
 537
 538         (if (and entry                  ; Make default entries unknown.
 539                  (or (null true) (eq true 'default))
 540                  (or (null false) (eq false 'default))
 541                  (eq write 'both))
 542             (setq cpp-edit-list (delq entry cpp-edit-list)
 543                   entry nil))
 544
 545         (if (> (length symbol) 39)
 546             (insert (substring symbol 0 39) ": ")
 547           (insert (format "%39s: " symbol)))
 548
 549         (cpp-make-button (cpp-face-name true)
 550                          'cpp-edit-true symbol t 14)
 551         (insert " ")
 552         (cpp-make-button (cpp-face-name false)
 553                          'cpp-edit-false symbol t 14)
 554         (insert " ")
 555         (cpp-make-button (car (rassq write cpp-branch-list))
 556                          'cpp-edit-write symbol nil 6)
 557         (insert "\n")))
 558     (insert "\n\n")
 559     (set-window-start nil start)
 560     (goto-char pos)))
 561
 562 (defun cpp-edit-load ()
 563   "Load cpp configuration."
 564   (interactive)
 565   (cond ((null init-file-user)
 566          ;; If -q was specified, don't load any init files.
 567          nil)
 568         ((file-readable-p cpp-config-file)
 569          (load-file cpp-config-file))
 570         ((file-readable-p (concat "~/" cpp-config-file))
 571          (load-file cpp-config-file)))
 572   (if (derived-mode-p 'cpp-edit-mode)
 573       (cpp-edit-reset)))
 574
 575 (defun cpp-edit-save ()
 576   "Save the current cpp configuration in a file."
 577   (interactive)
 578   (require 'pp)
 579   (with-current-buffer cpp-edit-buffer
 580     (let ((buffer (find-file-noselect cpp-config-file)))
 581       (set-buffer buffer)
 582       (erase-buffer)
 583       (pp (list 'setq 'cpp-known-face
 584                 (list 'quote cpp-known-face)) buffer)
 585       (pp (list 'setq 'cpp-unknown-face
 586                 (list 'quote cpp-unknown-face)) buffer)
 587       (pp (list 'setq 'cpp-face-type
 588                 (list 'quote cpp-face-type)) buffer)
 589       (pp (list 'setq 'cpp-known-writable
 590                 (list 'quote cpp-known-writable)) buffer)
 591       (pp (list 'setq 'cpp-unknown-writable
 592                 (list 'quote cpp-unknown-writable)) buffer)
 593       (pp (list 'setq 'cpp-edit-list
 594                 (list 'quote cpp-edit-list)) buffer)
 595       (write-file cpp-config-file))))
 596
 597 (defun cpp-edit-home ()
 598   "Switch back to original buffer."
 599   (interactive)
 600   (if cpp-button-event
 601       (read-event))
 602   (pop-to-buffer cpp-edit-buffer))
 603
 604 (defun cpp-edit-background ()
 605   "Change default face collection."
 606   (interactive)
 607   (call-interactively 'cpp-choose-default-face)
 608   (cpp-edit-reset))
 609
 610 (defun cpp-edit-known ()
 611   "Select default for known conditionals."
 612   (interactive)
 613   (setq cpp-known-face (cpp-choose-face "Known face" cpp-known-face))
 614   (cpp-edit-reset))
 615
 616 (defun cpp-edit-unknown ()
 617   "Select default for unknown conditionals."
 618   (interactive)
 619   (setq cpp-unknown-face (cpp-choose-face "Unknown face" cpp-unknown-face))
 620   (cpp-edit-reset))
 621
 622 (defun cpp-edit-toggle-known (arg)
 623   "Toggle writable status for known conditionals.
 624 With optional argument ARG, make them writable if ARG is positive,
 625 otherwise make them unwritable."
 626   (interactive "@P")
 627   (if (or (and (null arg) cpp-known-writable)
 628           (<= (prefix-numeric-value arg) 0))
 629       (setq cpp-known-writable nil)
 630     (setq cpp-known-writable t))
 631   (cpp-edit-reset))
 632
 633 (defun cpp-edit-toggle-unknown (arg)
 634   "Toggle writable status for unknown conditionals.
 635 With optional argument ARG, make them writable if ARG is positive,
 636 otherwise make them unwritable."
 637   (interactive "@P")
 638   (if (or (and (null arg) cpp-unknown-writable)
 639           (<= (prefix-numeric-value arg) 0))
 640       (setq cpp-unknown-writable nil)
 641     (setq cpp-unknown-writable t))
 642   (cpp-edit-reset))
 643
 644 (defun cpp-edit-true (symbol face)
 645   "Select SYMBOL's true FACE used for highlighting taken conditionals."
 646   (interactive
 647    (let ((symbol (cpp-choose-symbol)))
 648      (list symbol
 649            (cpp-choose-face "True face"
 650                             (nth 1 (assoc symbol cpp-edit-list))))))
 651   (setcar (nthcdr 1 (cpp-edit-list-entry-get-or-create symbol)) face)
 652   (cpp-edit-reset))
 653
 654 (defun cpp-edit-false (symbol face)
 655   "Select SYMBOL's false FACE used for highlighting untaken conditionals."
 656   (interactive
 657    (let ((symbol (cpp-choose-symbol)))
 658      (list symbol
 659            (cpp-choose-face "False face"
 660                             (nth 2 (assoc symbol cpp-edit-list))))))
 661   (setcar (nthcdr 2 (cpp-edit-list-entry-get-or-create symbol)) face)
 662   (cpp-edit-reset))
 663
 664 (defun cpp-edit-write (symbol branch)
 665   "Set which branches of SYMBOL should be writable to BRANCH.
 666 BRANCH should be either nil (false branch), t (true branch) or 'both."
 667   (interactive (list (cpp-choose-symbol) (cpp-choose-branch)))
 668   (setcar (nthcdr 3 (cpp-edit-list-entry-get-or-create symbol)) branch)
 669   (cpp-edit-reset))
 670
 671 (defun cpp-edit-list-entry-get-or-create (symbol)
 672   ;; Return the entry for SYMBOL in `cpp-edit-list'.
 673   ;; If it does not exist, create it.
 674   (let ((entry (assoc symbol cpp-edit-list)))
 675     (or entry
 676         (setq entry (list symbol nil nil 'both nil)
 677               cpp-edit-list (cons entry cpp-edit-list)))
 678     entry))
 679
 680 ;;; Prompts:
 681
 682 (defun cpp-choose-symbol ()
 683   ;; Choose a symbol if called from keyboard, otherwise use the one clicked on.
 684   (if cpp-button-event
 685       cpp-callback-data
 686     (completing-read "Symbol: " cpp-edit-symbols nil t)))
 687
 688 (defun cpp-choose-branch ()
 689   ;; Choose a branch, either nil, t, or both.
 690   (if cpp-button-event
 691       (x-popup-menu cpp-button-event
 692                     (list "Branch" (cons "Branch" cpp-branch-list)))
 693     (cdr (assoc (completing-read "Branch: " cpp-branch-list nil t)
 694                 cpp-branch-list))))
 695
 696 (defun cpp-choose-face (prompt default)
 697   ;; Choose a face from cpp-face-default-list.
 698   ;; PROMPT is what to say to the user.
 699   ;; DEFAULT is the default face.
 700   (or (if cpp-button-event
 701           (x-popup-menu cpp-button-event
 702                         (list prompt (cons prompt cpp-face-default-list)))
 703         (let ((name (car (rassq default cpp-face-default-list))))
 704           (cdr (assoc (completing-read (if name
 705                                            (concat prompt
 706                                                    " (default " name "): ")
 707                                          (concat prompt ": "))
 708                                        cpp-face-default-list nil t)
 709                       cpp-face-all-list))))
 710       default))
 711
 712 (defun cpp-choose-default-face (type)
 713   ;; Choose default face list for screen of TYPE.
 714   ;; Type must be one of the types defined in `cpp-face-type-list'.
 715   (interactive (list (if cpp-button-event
 716                          (x-popup-menu cpp-button-event
 717                                        (list "Screen type"
 718                                              (cons "Screen type"
 719                                                    cpp-face-type-list)))
 720                        (cdr (assoc (completing-read "Screen type: "
 721                                                     cpp-face-type-list
 722                                                     nil t)
 723                                    cpp-face-type-list)))))
 724   (cond ((null type))
 725         ((eq type 'light)
 726          (if cpp-face-light-list
 727              ()
 728            (setq cpp-face-light-list
 729                  (mapcar 'cpp-create-bg-face cpp-face-light-name-list))
 730            (setq cpp-face-all-list
 731                  (append cpp-face-all-list cpp-face-light-list)))
 732          (setq cpp-face-type 'light)
 733          (setq cpp-face-default-list
 734                (append cpp-face-light-list cpp-face-none-list)))
 735         ((eq type 'dark)
 736          (if cpp-face-dark-list
 737              ()
 738            (setq cpp-face-dark-list
 739                  (mapcar 'cpp-create-bg-face cpp-face-dark-name-list))
 740            (setq cpp-face-all-list
 741                  (append cpp-face-all-list cpp-face-dark-list)))
 742          (setq cpp-face-type 'dark)
 743          (setq cpp-face-default-list
 744                (append cpp-face-dark-list cpp-face-none-list)))
 745         ((eq type 'mono)
 746          (setq cpp-face-type 'mono)
 747          (setq cpp-face-default-list
 748                (append cpp-face-mono-list cpp-face-none-list)))
 749         (t
 750          (setq cpp-face-type 'none)
 751          (setq cpp-face-default-list cpp-face-none-list))))
 752
 753 ;;; Buttons:
 754
 755 (defun cpp-make-button (name callback &optional data face padding)
 756   ;; Create a button at point.
 757   ;; NAME is the name of the button.
 758   ;; CALLBACK is the function to call when the button is pushed.
 759   ;; DATA will be made available to CALLBACK
 760   ;;in the free variable cpp-callback-data.
 761   ;; FACE means that NAME is the name of a face in `cpp-face-all-list'.
 762   ;; PADDING means NAME will be right justified at that length.
 763   (let ((name (format "%s" name))
 764         from to)
 765     (cond ((null padding)
 766            (setq from (point))
 767            (insert name))
 768           ((> (length name) padding)
 769            (setq from (point))
 770            (insert (substring name 0 padding)))
 771           (t
 772            (insert (make-string (- padding (length name)) ? ))
 773            (setq from (point))
 774            (insert name)))
 775     (setq to (point))
 776     (setq face
 777           (if face
 778               (let ((check (cdr (assoc name cpp-face-all-list))))
 779                 (if (memq check '(default invisible))
 780                     'bold
 781                   check))
 782             'bold))
 783     (add-text-properties from to
 784                          (append (list 'face face)
 785                                  '(mouse-face highlight)
 786                                  '(help-echo "mouse-2: change/use this item")
 787                                  (list 'cpp-callback callback)
 788                                  (if data (list 'cpp-data data))))))
 789
 790 (defun cpp-push-button (event)
 791   ;; Pushed a CPP button.
 792   (interactive "@e")
 793   (set-buffer (window-buffer (posn-window (event-start event))))
 794   (let ((pos (posn-point (event-start event))))
 795     (let ((cpp-callback-data (get-text-property pos 'cpp-data))
 796           (fun (get-text-property pos 'cpp-callback))
 797           (cpp-button-event event))
 798       (cond (fun
 799              (call-interactively (get-text-property pos 'cpp-callback)))
 800             ((lookup-key global-map [ down-mouse-2])
 801              (call-interactively (lookup-key global-map [ down-mouse-2])))))))
 802
 803 ;;; Faces:
 804
 805 (defun cpp-create-bg-face (color)
 806   ;; Create entry for face with background COLOR.
 807   (cons color (cons 'background-color color)))
 808
 809 (cpp-choose-default-face
 810  (if (or window-system (display-color-p)) cpp-face-type 'none))
 811
 812 (defun cpp-face-name (face)
 813   ;; Return the name of FACE from `cpp-face-all-list'.
 814   (let ((entry (rassq (if face face 'default) cpp-face-all-list)))
 815     (if entry
 816         (car entry)
 817       (format "<%s>" face))))
 818
 819 ;;; Utilities:
 820
 821 (defvar cpp-progress-time 0)
 822 ;; Last time we issued a progress message.
 823
 824 (defun cpp-progress-message (&rest args)
 825   ;; Report progress at most once a second.  Take same ARGS as `message'.
 826   (let ((time (nth 1 (current-time))))
 827     (if (= time cpp-progress-time)
 828         ()
 829       (setq cpp-progress-time time)
 830       (apply 'message args))))
 831
 832 (provide 'cpp)
 833
 834 ;;; cpp.el ends here