lisp/gnus/gnus-util.el

   1 ;;; gnus-util.el --- utility functions for Gnus
   2
   3 ;; Copyright (C) 1996-2012 Free Software Foundation, Inc.
   4
   5 ;; Author: Lars Magne Ingebrigtsen <larsi@gnus.org>
   6 ;; Keywords: news
   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 ;; Nothing in this file depends on any other parts of Gnus -- all
  26 ;; functions and macros in this file are utility functions that are
  27 ;; used by Gnus and may be used by any other package without loading
  28 ;; Gnus first.
  29
  30 ;; [Unfortunately, it does depend on other parts of Gnus, e.g. the
  31 ;; autoloads and defvars below...]
  32
  33 ;;; Code:
  34
  35 ;; For Emacs <22.2 and XEmacs.
  36 (eval-and-compile
  37   (unless (fboundp 'declare-function) (defmacro declare-function (&rest r))))
  38 (eval-when-compile
  39   (require 'cl))
  40
  41 (require 'time-date)
  42
  43 (defcustom gnus-completing-read-function 'gnus-emacs-completing-read
  44   "Function use to do completing read."
  45   :version "24.1"
  46   :group 'gnus-meta
  47   :type `(radio (function-item
  48                  :doc "Use Emacs standard `completing-read' function."
  49                  gnus-emacs-completing-read)
  50                 ;; iswitchb.el is very old and ido.el is unavailable
  51                 ;; in XEmacs, so we exclude those function items.
  52                 ,@(unless (featurep 'xemacs)
  53                     '((function-item
  54                        :doc "Use `ido-completing-read' function."
  55                        gnus-ido-completing-read)
  56                       (function-item
  57                        :doc "Use iswitchb based completing-read function."
  58                        gnus-iswitchb-completing-read)))))
  59
  60 (defcustom gnus-completion-styles
  61   (if (and (boundp 'completion-styles-alist)
  62            (boundp 'completion-styles))
  63       (append (when (and (assq 'substring completion-styles-alist)
  64                          (not (memq 'substring completion-styles)))
  65                 (list 'substring))
  66               completion-styles)
  67     nil)
  68   "Value of `completion-styles' to use when completing."
  69   :version "24.1"
  70   :group 'gnus-meta
  71   :type 'list)
  72
  73 ;; Fixme: this should be a gnus variable, not nnmail-.
  74 (defvar nnmail-pathname-coding-system)
  75 (defvar nnmail-active-file-coding-system)
  76
  77 ;; Inappropriate references to other parts of Gnus.
  78 (defvar gnus-emphasize-whitespace-regexp)
  79 (defvar gnus-original-article-buffer)
  80 (defvar gnus-user-agent)
  81
  82 (autoload 'gnus-get-buffer-window "gnus-win")
  83 (autoload 'nnheader-narrow-to-headers "nnheader")
  84 (autoload 'nnheader-replace-chars-in-string "nnheader")
  85 (autoload 'mail-header-remove-comments "mail-parse")
  86
  87 (eval-and-compile
  88   (cond
  89    ;; Prefer `replace-regexp-in-string' (present in Emacs, XEmacs 21.5,
  90    ;; SXEmacs 22.1.4) over `replace-in-string'.  The latter leads to inf-loops
  91    ;; on empty matches:
  92    ;;   (replace-in-string "foo" "/*$" "/")
  93    ;;   (replace-in-string "xe" "\\(x\\)?" "")
  94    ((fboundp 'replace-regexp-in-string)
  95     (defun gnus-replace-in-string  (string regexp newtext &optional literal)
  96       "Replace all matches for REGEXP with NEWTEXT in STRING.
  97 If LITERAL is non-nil, insert NEWTEXT literally.  Return a new
  98 string containing the replacements.
  99
 100 This is a compatibility function for different Emacsen."
 101       (replace-regexp-in-string regexp newtext string nil literal)))
 102    ((fboundp 'replace-in-string)
 103     (defalias 'gnus-replace-in-string 'replace-in-string))))
 104
 105 (defun gnus-boundp (variable)
 106   "Return non-nil if VARIABLE is bound and non-nil."
 107   (and (boundp variable)
 108        (symbol-value variable)))
 109
 110 (defmacro gnus-eval-in-buffer-window (buffer &rest forms)
 111   "Pop to BUFFER, evaluate FORMS, and then return to the original window."
 112   (let ((tempvar (make-symbol "GnusStartBufferWindow"))
 113         (w (make-symbol "w"))
 114         (buf (make-symbol "buf")))
 115     `(let* ((,tempvar (selected-window))
 116             (,buf ,buffer)
 117             (,w (gnus-get-buffer-window ,buf 'visible)))
 118        (unwind-protect
 119            (progn
 120              (if ,w
 121                  (progn
 122                    (select-window ,w)
 123                    (set-buffer (window-buffer ,w)))
 124                (pop-to-buffer ,buf))
 125              ,@forms)
 126          (select-window ,tempvar)))))
 127
 128 (put 'gnus-eval-in-buffer-window 'lisp-indent-function 1)
 129 (put 'gnus-eval-in-buffer-window 'edebug-form-spec '(form body))
 130
 131 (defmacro gnus-intern-safe (string hashtable)
 132   "Get hash value.  Arguments are STRING and HASHTABLE."
 133   `(let ((symbol (intern ,string ,hashtable)))
 134      (or (boundp symbol)
 135          (set symbol nil))
 136      symbol))
 137
 138 (defsubst gnus-goto-char (point)
 139   (and point (goto-char point)))
 140
 141 (defmacro gnus-buffer-exists-p (buffer)
 142   `(let ((buffer ,buffer))
 143      (when buffer
 144        (funcall (if (stringp buffer) 'get-buffer 'buffer-name)
 145                 buffer))))
 146
 147 ;; The LOCAL arg to `add-hook' is interpreted differently in Emacs and
 148 ;; XEmacs.  In Emacs we don't need to call `make-local-hook' first.
 149 ;; It's harmless, though, so the main purpose of this alias is to shut
 150 ;; up the byte compiler.
 151 (defalias 'gnus-make-local-hook (if (featurep 'xemacs)
 152                                     'make-local-hook
 153                                   'ignore))
 154
 155 (defun gnus-delete-first (elt list)
 156   "Delete by side effect the first occurrence of ELT as a member of LIST."
 157   (if (equal (car list) elt)
 158       (cdr list)
 159     (let ((total list))
 160       (while (and (cdr list)
 161                   (not (equal (cadr list) elt)))
 162         (setq list (cdr list)))
 163       (when (cdr list)
 164         (setcdr list (cddr list)))
 165       total)))
 166
 167 ;; Delete the current line (and the next N lines).
 168 (defmacro gnus-delete-line (&optional n)
 169   `(delete-region (point-at-bol)
 170                   (progn (forward-line ,(or n 1)) (point))))
 171
 172 (defun gnus-extract-address-components (from)
 173   "Extract address components from a From header.
 174 Given an RFC-822 address FROM, extract full name and canonical address.
 175 Returns a list of the form (FULL-NAME CANONICAL-ADDRESS).  Much more simple
 176 solution than `mail-extract-address-components', which works much better, but
 177 is slower."
 178   (let (name address)
 179     ;; First find the address - the thing with the @ in it.  This may
 180     ;; not be accurate in mail addresses, but does the trick most of
 181     ;; the time in news messages.
 182     (cond (;; Check ``<foo@bar>'' first in order to handle the quite common
 183            ;; form ``"abc@xyz" <foo@bar>'' (i.e. ``@'' as part of a comment)
 184            ;; correctly.
 185            (string-match "<\\([^@ \t<>]+[!@][^@ \t<>]+\\)>" from)
 186            (setq address (substring from (match-beginning 1) (match-end 1))))
 187           ((string-match "\\b[^@ \t<>]+[!@][^@ \t<>]+\\b" from)
 188            (setq address (substring from (match-beginning 0) (match-end 0)))))
 189     ;; Then we check whether the "name <address>" format is used.
 190     (and address
 191          ;; Linear white space is not required.
 192          (string-match (concat "[ \t]*<" (regexp-quote address) ">") from)
 193          (and (setq name (substring from 0 (match-beginning 0)))
 194               ;; Strip any quotes from the name.
 195               (string-match "^\".*\"$" name)
 196               (setq name (substring name 1 (1- (match-end 0))))))
 197     ;; If not, then "address (name)" is used.
 198     (or name
 199         (and (string-match "(.+)" from)
 200              (setq name (substring from (1+ (match-beginning 0))
 201                                    (1- (match-end 0)))))
 202         (and (string-match "()" from)
 203              (setq name address))
 204         ;; XOVER might not support folded From headers.
 205         (and (string-match "(.*" from)
 206              (setq name (substring from (1+ (match-beginning 0))
 207                                    (match-end 0)))))
 208     (list (if (string= name "") nil name) (or address from))))
 209
 210 (declare-function message-fetch-field "message" (header &optional not-all))
 211
 212 (defun gnus-fetch-field (field)
 213   "Return the value of the header FIELD of current article."
 214   (require 'message)
 215   (save-excursion
 216     (save-restriction
 217       (let ((inhibit-point-motion-hooks t))
 218         (nnheader-narrow-to-headers)
 219         (message-fetch-field field)))))
 220
 221 (defun gnus-fetch-original-field (field)
 222   "Fetch FIELD from the original version of the current article."
 223   (with-current-buffer gnus-original-article-buffer
 224     (gnus-fetch-field field)))
 225
 226
 227 (defun gnus-goto-colon ()
 228   (beginning-of-line)
 229   (let ((eol (point-at-eol)))
 230     (goto-char (or (text-property-any (point) eol 'gnus-position t)
 231                    (search-forward ":" eol t)
 232                    (point)))))
 233
 234 (declare-function gnus-find-method-for-group "gnus" (group &optional info))
 235 (declare-function gnus-group-name-decode "gnus-group" (string charset))
 236 (declare-function gnus-group-name-charset "gnus-group" (method group))
 237 ;; gnus-group requires gnus-int which requires message.
 238 (declare-function message-tokenize-header "message"
 239                   (header &optional separator))
 240
 241 (defun gnus-decode-newsgroups (newsgroups group &optional method)
 242   (require 'gnus-group)
 243   (let ((method (or method (gnus-find-method-for-group group))))
 244     (mapconcat (lambda (group)
 245                  (gnus-group-name-decode group (gnus-group-name-charset
 246                                                 method group)))
 247                (message-tokenize-header newsgroups)
 248                ",")))
 249
 250 (defun gnus-remove-text-with-property (prop)
 251   "Delete all text in the current buffer with text property PROP."
 252   (let ((start (point-min))
 253         end)
 254     (unless (get-text-property start prop)
 255       (setq start (next-single-property-change start prop)))
 256     (while start
 257       (setq end (text-property-any start (point-max) prop nil))
 258       (delete-region start (or end (point-max)))
 259       (setq start (when end
 260                     (next-single-property-change start prop))))))
 261
 262 (defun gnus-find-text-property-region (start end prop)
 263   "Return a list of text property regions that has property PROP."
 264   (let (regions value)
 265     (unless (get-text-property start prop)
 266       (setq start (next-single-property-change start prop)))
 267     (while start
 268       (setq value (get-text-property start prop)
 269             end (text-property-not-all start (point-max) prop value))
 270       (if (not end)
 271           (setq start nil)
 272         (when value
 273           (push (list (set-marker (make-marker) start)
 274                       (set-marker (make-marker) end)
 275                       value)
 276                 regions))
 277         (setq start (next-single-property-change start prop))))
 278     (nreverse regions)))
 279
 280 (defun gnus-newsgroup-directory-form (newsgroup)
 281   "Make hierarchical directory name from NEWSGROUP name."
 282   (let* ((newsgroup (gnus-newsgroup-savable-name newsgroup))
 283          (idx (string-match ":" newsgroup)))
 284     (concat
 285      (if idx (substring newsgroup 0 idx))
 286      (if idx "/")
 287      (nnheader-replace-chars-in-string
 288       (if idx (substring newsgroup (1+ idx)) newsgroup)
 289       ?. ?/))))
 290
 291 (defun gnus-newsgroup-savable-name (group)
 292   ;; Replace any slashes in a group name (eg. an ange-ftp nndoc group)
 293   ;; with dots.
 294   (nnheader-replace-chars-in-string group ?/ ?.))
 295
 296 (defun gnus-string> (s1 s2)
 297   (not (or (string< s1 s2)
 298            (string= s1 s2))))
 299
 300 (defun gnus-string< (s1 s2)
 301   "Return t if first arg string is less than second in lexicographic order.
 302 Case is significant if and only if `case-fold-search' is nil.
 303 Symbols are also allowed; their print names are used instead."
 304   (if case-fold-search
 305       (string-lessp (downcase (if (symbolp s1) (symbol-name s1) s1))
 306                     (downcase (if (symbolp s2) (symbol-name s2) s2)))
 307     (string-lessp s1 s2)))
 308
 309 ;;; Time functions.
 310
 311 (defun gnus-file-newer-than (file date)
 312   (let ((fdate (nth 5 (file-attributes file))))
 313     (or (> (car fdate) (car date))
 314         (and (= (car fdate) (car date))
 315              (> (nth 1 fdate) (nth 1 date))))))
 316
 317 ;; Every version of Emacs Gnus supports has built-in float-time.
 318 ;; The featurep test silences an irritating compiler warning.
 319 (eval-and-compile
 320   (if (or (featurep 'emacs)
 321           (fboundp 'float-time))
 322       (defalias 'gnus-float-time 'float-time)
 323     (defun gnus-float-time (&optional time)
 324       "Convert time value TIME to a floating point number.
 325 TIME defaults to the current time."
 326       (time-to-seconds (or time (current-time))))))
 327
 328 ;;; Keymap macros.
 329
 330 (defmacro gnus-local-set-keys (&rest plist)
 331   "Set the keys in PLIST in the current keymap."
 332   `(gnus-define-keys-1 (current-local-map) ',plist))
 333
 334 (defmacro gnus-define-keys (keymap &rest plist)
 335   "Define all keys in PLIST in KEYMAP."
 336   `(gnus-define-keys-1 (quote ,keymap) (quote ,plist)))
 337
 338 (defmacro gnus-define-keys-safe (keymap &rest plist)
 339   "Define all keys in PLIST in KEYMAP without overwriting previous definitions."
 340   `(gnus-define-keys-1 (quote ,keymap) (quote ,plist) t))
 341
 342 (put 'gnus-define-keys 'lisp-indent-function 1)
 343 (put 'gnus-define-keys-safe 'lisp-indent-function 1)
 344 (put 'gnus-local-set-keys 'lisp-indent-function 1)
 345
 346 (defmacro gnus-define-keymap (keymap &rest plist)
 347   "Define all keys in PLIST in KEYMAP."
 348   `(gnus-define-keys-1 ,keymap (quote ,plist)))
 349
 350 (put 'gnus-define-keymap 'lisp-indent-function 1)
 351
 352 (defun gnus-define-keys-1 (keymap plist &optional safe)
 353   (when (null keymap)
 354     (error "Can't set keys in a null keymap"))
 355   (cond ((symbolp keymap)
 356          (setq keymap (symbol-value keymap)))
 357         ((keymapp keymap))
 358         ((listp keymap)
 359          (set (car keymap) nil)
 360          (define-prefix-command (car keymap))
 361          (define-key (symbol-value (caddr keymap)) (cadr keymap) (car keymap))
 362          (setq keymap (symbol-value (car keymap)))))
 363   (let (key)
 364     (while plist
 365       (when (symbolp (setq key (pop plist)))
 366         (setq key (symbol-value key)))
 367       (if (or (not safe)
 368               (eq (lookup-key keymap key) 'undefined))
 369           (define-key keymap key (pop plist))
 370         (pop plist)))))
 371
 372 (defun gnus-y-or-n-p (prompt)
 373   (prog1
 374       (y-or-n-p prompt)
 375     (message "")))
 376 (defun gnus-yes-or-no-p (prompt)
 377   (prog1
 378       (yes-or-no-p prompt)
 379     (message "")))
 380
 381 ;; By Frank Schmitt <ich@Frank-Schmitt.net>. Allows to have
 382 ;; age-depending date representations. (e.g. just the time if it's
 383 ;; from today, the day of the week if it's within the last 7 days and
 384 ;; the full date if it's older)
 385
 386 (defun gnus-seconds-today ()
 387   "Return the number of seconds passed today."
 388   (let ((now (decode-time (current-time))))
 389     (+ (car now) (* (car (cdr now)) 60) (* (car (nthcdr 2 now)) 3600))))
 390
 391 (defun gnus-seconds-month ()
 392   "Return the number of seconds passed this month."
 393   (let ((now (decode-time (current-time))))
 394     (+ (car now) (* (car (cdr now)) 60) (* (car (nthcdr 2 now)) 3600)
 395        (* (- (car (nthcdr 3 now)) 1) 3600 24))))
 396
 397 (defun gnus-seconds-year ()
 398   "Return the number of seconds passed this year."
 399   (let ((now (decode-time (current-time)))
 400         (days (format-time-string "%j" (current-time))))
 401     (+ (car now) (* (car (cdr now)) 60) (* (car (nthcdr 2 now)) 3600)
 402        (* (- (string-to-number days) 1) 3600 24))))
 403
 404 (defmacro gnus-date-get-time (date)
 405   "Convert DATE string to Emacs time.
 406 Cache the result as a text property stored in DATE."
 407   ;; Either return the cached value...
 408   `(let ((d ,date))
 409      (if (equal "" d)
 410          '(0 0)
 411        (or (get-text-property 0 'gnus-time d)
 412            ;; or compute the value...
 413            (let ((time (safe-date-to-time d)))
 414              ;; and store it back in the string.
 415              (put-text-property 0 1 'gnus-time time d)
 416              time)))))
 417
 418 (defun gnus-dd-mmm (messy-date)
 419   "Return a string like DD-MMM from a big messy string."
 420   (condition-case ()
 421       (format-time-string "%d-%b" (gnus-date-get-time messy-date))
 422     (error "  -   ")))
 423
 424 (defsubst gnus-time-iso8601 (time)
 425   "Return a string of TIME in YYYYMMDDTHHMMSS format."
 426   (format-time-string "%Y%m%dT%H%M%S" time))
 427
 428 (defun gnus-date-iso8601 (date)
 429   "Convert the DATE to YYYYMMDDTHHMMSS."
 430   (condition-case ()
 431       (gnus-time-iso8601 (gnus-date-get-time date))
 432     (error "")))
 433
 434 (defun gnus-mode-string-quote (string)
 435   "Quote all \"%\"'s in STRING."
 436   (gnus-replace-in-string string "%" "%%"))
 437
 438 ;; Make a hash table (default and minimum size is 256).
 439 ;; Optional argument HASHSIZE specifies the table size.
 440 (defun gnus-make-hashtable (&optional hashsize)
 441   (make-vector (if hashsize (max (gnus-create-hash-size hashsize) 256) 256) 0))
 442
 443 ;; Make a number that is suitable for hashing; bigger than MIN and
 444 ;; equal to some 2^x.  Many machines (such as sparcs) do not have a
 445 ;; hardware modulo operation, so they implement it in software.  On
 446 ;; many sparcs over 50% of the time to intern is spent in the modulo.
 447 ;; Yes, it's slower than actually computing the hash from the string!
 448 ;; So we use powers of 2 so people can optimize the modulo to a mask.
 449 (defun gnus-create-hash-size (min)
 450   (let ((i 1))
 451     (while (< i min)
 452       (setq i (* 2 i)))
 453     i))
 454
 455 (defcustom gnus-verbose 6
 456   "*Integer that says how verbose Gnus should be.
 457 The higher the number, the more messages Gnus will flash to say what
 458 it's doing.  At zero, Gnus will be totally mute; at five, Gnus will
 459 display most important messages; and at ten, Gnus will keep on
 460 jabbering all the time."
 461   :version "24.1"
 462   :group 'gnus-start
 463   :type 'integer)
 464
 465 (defcustom gnus-add-timestamp-to-message nil
 466   "Non-nil means add timestamps to messages that Gnus issues.
 467 If it is `log', add timestamps to only the messages that go into the
 468 \"*Messages*\" buffer (in XEmacs, it is the \" *Message-Log*\" buffer).
 469 If it is neither nil nor `log', add timestamps not only to log messages
 470 but also to the ones displayed in the echo area."
 471   :version "23.1" ;; No Gnus
 472   :group  'gnus-various
 473   :type '(choice :format "%{%t%}:\n %[Value Menu%] %v"
 474                  (const :tag "Logged messages only" log)
 475                  (sexp :tag "All messages"
 476                        :match (lambda (widget value) value)
 477                        :value t)
 478                  (const :tag "No timestamp" nil)))
 479
 480 (eval-when-compile
 481   (defmacro gnus-message-with-timestamp-1 (format-string args)
 482     (let ((timestamp '(format-time-string "%Y%m%dT%H%M%S.%3N> " time)))
 483       (if (featurep 'xemacs)
 484           `(let (str time)
 485              (if (or (and (null ,format-string) (null ,args))
 486                      (progn
 487                        (setq str (apply 'format ,format-string ,args))
 488                        (zerop (length str))))
 489                  (prog1
 490                      (and ,format-string str)
 491                    (clear-message nil))
 492                (cond ((eq gnus-add-timestamp-to-message 'log)
 493                       (setq time (current-time))
 494                       (display-message 'no-log str)
 495                       (log-message 'message (concat ,timestamp str)))
 496                      (gnus-add-timestamp-to-message
 497                       (setq time (current-time))
 498                       (display-message 'message (concat ,timestamp str)))
 499                      (t
 500                       (display-message 'message str))))
 501              str)
 502         `(let (str time)
 503            (cond ((eq gnus-add-timestamp-to-message 'log)
 504                   (setq str (let (message-log-max)
 505                               (apply 'message ,format-string ,args)))
 506                   (when (and message-log-max
 507                              (> message-log-max 0)
 508                              (/= (length str) 0))
 509                     (setq time (current-time))
 510                     (with-current-buffer (get-buffer-create "*Messages*")
 511                       (goto-char (point-max))
 512                       (insert ,timestamp str "\n")
 513                       (forward-line (- message-log-max))
 514                       (delete-region (point-min) (point))
 515                       (goto-char (point-max))))
 516                   str)
 517                  (gnus-add-timestamp-to-message
 518                   (if (or (and (null ,format-string) (null ,args))
 519                           (progn
 520                             (setq str (apply 'format ,format-string ,args))
 521                             (zerop (length str))))
 522                       (prog1
 523                           (and ,format-string str)
 524                         (message nil))
 525                     (setq time (current-time))
 526                     (message "%s" (concat ,timestamp str))
 527                     str))
 528                  (t
 529                   (apply 'message ,format-string ,args))))))))
 530
 531 (defvar gnus-action-message-log nil)
 532
 533 (defun gnus-message-with-timestamp (format-string &rest args)
 534   "Display message with timestamp.  Arguments are the same as `message'.
 535 The `gnus-add-timestamp-to-message' variable controls how to add
 536 timestamp to message."
 537   (gnus-message-with-timestamp-1 format-string args))
 538
 539 (defun gnus-message (level &rest args)
 540   "If LEVEL is lower than `gnus-verbose' print ARGS using `message'.
 541
 542 Guideline for numbers:
 543 1 - error messages, 3 - non-serious error messages, 5 - messages for things
 544 that take a long time, 7 - not very important messages on stuff, 9 - messages
 545 inside loops."
 546   (if (<= level gnus-verbose)
 547       (let ((message
 548              (if gnus-add-timestamp-to-message
 549                  (apply 'gnus-message-with-timestamp args)
 550                (apply 'message args))))
 551         (when (and (consp gnus-action-message-log)
 552                    (<= level 3))
 553           (push message gnus-action-message-log))
 554         message)
 555     ;; We have to do this format thingy here even if the result isn't
 556     ;; shown - the return value has to be the same as the return value
 557     ;; from `message'.
 558     (apply 'format args)))
 559
 560 (defun gnus-final-warning ()
 561   (when (and (consp gnus-action-message-log)
 562              (setq gnus-action-message-log
 563                    (delete nil gnus-action-message-log)))
 564     (message "Warning: %s"
 565              (mapconcat #'identity gnus-action-message-log "; "))))
 566
 567 (defun gnus-error (level &rest args)
 568   "Beep an error if LEVEL is equal to or less than `gnus-verbose'.
 569 ARGS are passed to `message'."
 570   (when (<= (floor level) gnus-verbose)
 571     (apply 'message args)
 572     (ding)
 573     (let (duration)
 574       (when (and (floatp level)
 575                  (not (zerop (setq duration (* 10 (- level (floor level)))))))
 576         (sit-for duration))))
 577   nil)
 578
 579 (defun gnus-split-references (references)
 580   "Return a list of Message-IDs in REFERENCES."
 581   (let ((beg 0)
 582         (references (mail-header-remove-comments (or references "")))
 583         ids)
 584     (while (string-match "<[^<]+[^< \t]" references beg)
 585       (push (substring references (match-beginning 0) (setq beg (match-end 0)))
 586             ids))
 587     (nreverse ids)))
 588
 589 (defun gnus-extract-references (references)
 590   "Return a list of Message-IDs in REFERENCES (in In-Reply-To
 591   format), trimmed to only contain the Message-IDs."
 592   (let ((ids (gnus-split-references references))
 593         refs)
 594     (dolist (id ids)
 595       (when (string-match "<[^<>]+>" id)
 596         (push (match-string 0 id) refs)))
 597     refs))
 598
 599 (defsubst gnus-parent-id (references &optional n)
 600   "Return the last Message-ID in REFERENCES.
 601 If N, return the Nth ancestor instead."
 602   (when (and references
 603              (not (zerop (length references))))
 604     (if n
 605         (let ((ids (inline (gnus-split-references references))))
 606           (while (nthcdr n ids)
 607             (setq ids (cdr ids)))
 608           (car ids))
 609       (let ((references (mail-header-remove-comments references)))
 610         (when (string-match "\\(<[^<]+>\\)[ \t]*\\'" references)
 611           (match-string 1 references))))))
 612
 613 (defsubst gnus-buffer-live-p (buffer)
 614   "Say whether BUFFER is alive or not."
 615   (and buffer (buffer-live-p (get-buffer buffer))))
 616
 617 (defun gnus-horizontal-recenter ()
 618   "Recenter the current buffer horizontally."
 619   (if (< (current-column) (/ (window-width) 2))
 620       (set-window-hscroll (gnus-get-buffer-window (current-buffer) t) 0)
 621     (let* ((orig (point))
 622            (end (window-end (gnus-get-buffer-window (current-buffer) t)))
 623            (max 0))
 624       (when end
 625         ;; Find the longest line currently displayed in the window.
 626         (goto-char (window-start))
 627         (while (and (not (eobp))
 628                     (< (point) end))
 629           (end-of-line)
 630           (setq max (max max (current-column)))
 631           (forward-line 1))
 632         (goto-char orig)
 633         ;; Scroll horizontally to center (sort of) the point.
 634         (if (> max (window-width))
 635             (set-window-hscroll
 636              (gnus-get-buffer-window (current-buffer) t)
 637              (min (- (current-column) (/ (window-width) 3))
 638                   (+ 2 (- max (window-width)))))
 639           (set-window-hscroll (gnus-get-buffer-window (current-buffer) t) 0))
 640         max))))
 641
 642 (defun gnus-read-event-char (&optional prompt)
 643   "Get the next event."
 644   (let ((event (read-event prompt)))
 645     ;; should be gnus-characterp, but this can't be called in XEmacs anyway
 646     (cons (and (numberp event) event) event)))
 647
 648 (defun gnus-copy-file (file &optional to)
 649   "Copy FILE to TO."
 650   (interactive
 651    (list (read-file-name "Copy file: " default-directory)
 652          (read-file-name "Copy file to: " default-directory)))
 653   (unless to
 654     (setq to (read-file-name "Copy file to: " default-directory)))
 655   (when (file-directory-p to)
 656     (setq to (concat (file-name-as-directory to)
 657                      (file-name-nondirectory file))))
 658   (copy-file file to))
 659
 660 (defvar gnus-work-buffer " *gnus work*")
 661
 662 (declare-function gnus-get-buffer-create "gnus" (name))
 663 ;; gnus.el requires mm-util.
 664 (declare-function mm-enable-multibyte "mm-util")
 665
 666 (defun gnus-set-work-buffer ()
 667   "Put point in the empty Gnus work buffer."
 668   (if (get-buffer gnus-work-buffer)
 669       (progn
 670         (set-buffer gnus-work-buffer)
 671         (erase-buffer))
 672     (set-buffer (gnus-get-buffer-create gnus-work-buffer))
 673     (kill-all-local-variables)
 674     (mm-enable-multibyte)))
 675
 676 (defmacro gnus-group-real-name (group)
 677   "Find the real name of a foreign newsgroup."
 678   `(let ((gname ,group))
 679      (if (string-match "^[^:]+:" gname)
 680          (substring gname (match-end 0))
 681        gname)))
 682
 683 (defmacro gnus-group-server (group)
 684   "Find the server name of a foreign newsgroup.
 685 For example, (gnus-group-server \"nnimap+yxa:INBOX.foo\") would
 686 yield \"nnimap:yxa\"."
 687   `(let ((gname ,group))
 688      (if (string-match "^\\([^:+]+\\)\\(?:\\+\\([^:]*\\)\\)?:" gname)
 689          (format "%s:%s" (match-string 1 gname) (or
 690                                                  (match-string 2 gname)
 691                                                  ""))
 692        (format "%s:%s" (car gnus-select-method) (cadr gnus-select-method)))))
 693
 694 (defun gnus-make-sort-function (funs)
 695   "Return a composite sort condition based on the functions in FUNS."
 696   (cond
 697    ;; Just a simple function.
 698    ((functionp funs) funs)
 699    ;; No functions at all.
 700    ((null funs) funs)
 701    ;; A list of functions.
 702    ((or (cdr funs)
 703         (listp (car funs)))
 704     (gnus-byte-compile
 705      `(lambda (t1 t2)
 706         ,(gnus-make-sort-function-1 (reverse funs)))))
 707    ;; A list containing just one function.
 708    (t
 709     (car funs))))
 710
 711 (defun gnus-make-sort-function-1 (funs)
 712   "Return a composite sort condition based on the functions in FUNS."
 713   (let ((function (car funs))
 714         (first 't1)
 715         (last 't2))
 716     (when (consp function)
 717       (cond
 718        ;; Reversed spec.
 719        ((eq (car function) 'not)
 720         (setq function (cadr function)
 721               first 't2
 722               last 't1))
 723        ((functionp function)
 724         ;; Do nothing.
 725         )
 726        (t
 727         (error "Invalid sort spec: %s" function))))
 728     (if (cdr funs)
 729         `(or (,function ,first ,last)
 730              (and (not (,function ,last ,first))
 731                   ,(gnus-make-sort-function-1 (cdr funs))))
 732       `(,function ,first ,last))))
 733
 734 (defun gnus-turn-off-edit-menu (type)
 735   "Turn off edit menu in `gnus-TYPE-mode-map'."
 736   (define-key (symbol-value (intern (format "gnus-%s-mode-map" type)))
 737     [menu-bar edit] 'undefined))
 738
 739 (defmacro gnus-bind-print-variables (&rest forms)
 740   "Bind print-* variables and evaluate FORMS.
 741 This macro is used with `prin1', `pp', etc. in order to ensure printed
 742 Lisp objects are loadable.  Bind `print-quoted' and `print-readably'
 743 to t, and `print-escape-multibyte', `print-escape-newlines',
 744 `print-escape-nonascii', `print-length', `print-level' and
 745 `print-string-length' to nil."
 746   `(let ((print-quoted t)
 747          (print-readably t)
 748          ;;print-circle
 749          ;;print-continuous-numbering
 750          print-escape-multibyte
 751          print-escape-newlines
 752          print-escape-nonascii
 753          ;;print-gensym
 754          print-length
 755          print-level
 756          print-string-length)
 757      ,@forms))
 758
 759 (defun gnus-prin1 (form)
 760   "Use `prin1' on FORM in the current buffer.
 761 Bind `print-quoted' and `print-readably' to t, and `print-length' and
 762 `print-level' to nil.  See also `gnus-bind-print-variables'."
 763   (gnus-bind-print-variables (prin1 form (current-buffer))))
 764
 765 (defun gnus-prin1-to-string (form)
 766   "The same as `prin1'.
 767 Bind `print-quoted' and `print-readably' to t, and `print-length' and
 768 `print-level' to nil.  See also `gnus-bind-print-variables'."
 769   (gnus-bind-print-variables (prin1-to-string form)))
 770
 771 (defun gnus-pp (form &optional stream)
 772   "Use `pp' on FORM in the current buffer.
 773 Bind `print-quoted' and `print-readably' to t, and `print-length' and
 774 `print-level' to nil.  See also `gnus-bind-print-variables'."
 775   (gnus-bind-print-variables (pp form (or stream (current-buffer)))))
 776
 777 (defun gnus-pp-to-string (form)
 778   "The same as `pp-to-string'.
 779 Bind `print-quoted' and `print-readably' to t, and `print-length' and
 780 `print-level' to nil.  See also `gnus-bind-print-variables'."
 781   (gnus-bind-print-variables (pp-to-string form)))
 782
 783 (defun gnus-make-directory (directory)
 784   "Make DIRECTORY (and all its parents) if it doesn't exist."
 785   (require 'nnmail)
 786   (let ((file-name-coding-system nnmail-pathname-coding-system))
 787     (when (and directory
 788                (not (file-exists-p directory)))
 789       (make-directory directory t)))
 790   t)
 791
 792 (defun gnus-write-buffer (file)
 793   "Write the current buffer's contents to FILE."
 794   (require 'nnmail)
 795   (let ((file-name-coding-system nnmail-pathname-coding-system))
 796     ;; Make sure the directory exists.
 797     (gnus-make-directory (file-name-directory file))
 798     ;; Write the buffer.
 799     (write-region (point-min) (point-max) file nil 'quietly)))
 800
 801 (defun gnus-delete-file (file)
 802   "Delete FILE if it exists."
 803   (when (file-exists-p file)
 804     (delete-file file)))
 805
 806 (defun gnus-delete-duplicates (list)
 807   "Remove duplicate entries from LIST."
 808   (let ((result nil))
 809     (while list
 810       (unless (member (car list) result)
 811         (push (car list) result))
 812       (pop list))
 813     (nreverse result)))
 814
 815 (defun gnus-delete-directory (directory)
 816   "Delete files in DIRECTORY.  Subdirectories remain.
 817 If there's no subdirectory, delete DIRECTORY as well."
 818   (when (file-directory-p directory)
 819     (let ((files (directory-files
 820                   directory t "^\\([^.]\\|\\.\\([^.]\\|\\..\\)\\).*"))
 821           file dir)
 822       (while files
 823         (setq file (pop files))
 824         (if (eq t (car (file-attributes file)))
 825             ;; `file' is a subdirectory.
 826             (setq dir t)
 827           ;; `file' is a file or a symlink.
 828           (delete-file file)))
 829       (unless dir
 830         (delete-directory directory)))))
 831
 832 (defun gnus-strip-whitespace (string)
 833   "Return STRING stripped of all whitespace."
 834   (while (string-match "[\r\n\t ]+" string)
 835     (setq string (replace-match "" t t string)))
 836   string)
 837
 838 (declare-function gnus-put-text-property "gnus"
 839                   (start end property value &optional object))
 840
 841 (defsubst gnus-put-text-property-excluding-newlines (beg end prop val)
 842   "The same as `put-text-property', but don't put this prop on any newlines in the region."
 843   (save-match-data
 844     (save-excursion
 845       (save-restriction
 846         (goto-char beg)
 847         (while (re-search-forward gnus-emphasize-whitespace-regexp end 'move)
 848           (gnus-put-text-property beg (match-beginning 0) prop val)
 849           (setq beg (point)))
 850         (gnus-put-text-property beg (point) prop val)))))
 851
 852 (declare-function gnus-overlay-put  "gnus" (overlay prop value))
 853 (declare-function gnus-make-overlay "gnus"
 854                   (beg end &optional buffer front-advance rear-advance))
 855
 856 (defsubst gnus-put-overlay-excluding-newlines (beg end prop val)
 857   "The same as `put-text-property', but don't put this prop on any newlines in the region."
 858   (save-match-data
 859     (save-excursion
 860       (save-restriction
 861         (goto-char beg)
 862         (while (re-search-forward gnus-emphasize-whitespace-regexp end 'move)
 863           (gnus-overlay-put
 864            (gnus-make-overlay beg (match-beginning 0))
 865            prop val)
 866           (setq beg (point)))
 867         (gnus-overlay-put (gnus-make-overlay beg (point)) prop val)))))
 868
 869 (defun gnus-put-text-property-excluding-characters-with-faces (beg end
 870                                                                    prop val)
 871   "The same as `put-text-property', but don't put props on characters with the `gnus-face' property."
 872   (let ((b beg))
 873     (while (/= b end)
 874       (when (get-text-property b 'gnus-face)
 875         (setq b (next-single-property-change b 'gnus-face nil end)))
 876       (when (/= b end)
 877         (inline
 878           (gnus-put-text-property
 879            b (setq b (next-single-property-change b 'gnus-face nil end))
 880            prop val))))))
 881
 882 (defmacro gnus-faces-at (position)
 883   "Return a list of faces at POSITION."
 884   (if (featurep 'xemacs)
 885       `(let ((pos ,position))
 886          (mapcar-extents 'extent-face
 887                          nil (current-buffer) pos pos nil 'face))
 888     `(let ((pos ,position))
 889        (delq nil (cons (get-text-property pos 'face)
 890                        (mapcar
 891                         (lambda (overlay)
 892                           (overlay-get overlay 'face))
 893                         (overlays-at pos)))))))
 894
 895 (if (fboundp 'invisible-p)
 896     (defalias 'gnus-invisible-p 'invisible-p)
 897   ;; for Emacs < 22.2, and XEmacs.
 898   (defun gnus-invisible-p (pos)
 899     "Return non-nil if the character after POS is currently invisible."
 900     (let ((prop (get-char-property pos 'invisible)))
 901       (if (eq buffer-invisibility-spec t)
 902           prop
 903         (or (memq prop buffer-invisibility-spec)
 904             (assq prop buffer-invisibility-spec))))))
 905
 906 ;; Note: the optional 2nd argument has a different meaning between
 907 ;; Emacs and XEmacs.
 908 ;; (next-char-property-change POSITION &optional LIMIT)
 909 ;; (next-extent-change        POS      &optional OBJECT)
 910 (defalias 'gnus-next-char-property-change
 911   (if (fboundp 'next-extent-change)
 912       'next-extent-change 'next-char-property-change))
 913
 914 (defalias 'gnus-previous-char-property-change
 915   (if (fboundp 'previous-extent-change)
 916       'previous-extent-change 'previous-char-property-change))
 917
 918 ;;; Protected and atomic operations.  dmoore@ucsd.edu 21.11.1996
 919 ;; The primary idea here is to try to protect internal datastructures
 920 ;; from becoming corrupted when the user hits C-g, or if a hook or
 921 ;; similar blows up.  Often in Gnus multiple tables/lists need to be
 922 ;; updated at the same time, or information can be lost.
 923
 924 (defvar gnus-atomic-be-safe t
 925   "If t, certain operations will be protected from interruption by C-g.")
 926
 927 (defmacro gnus-atomic-progn (&rest forms)
 928   "Evaluate FORMS atomically, which means to protect the evaluation
 929 from being interrupted by the user.  An error from the forms themselves
 930 will return without finishing the operation.  Since interrupts from
 931 the user are disabled, it is recommended that only the most minimal
 932 operations are performed by FORMS.  If you wish to assign many
 933 complicated values atomically, compute the results into temporary
 934 variables and then do only the assignment atomically."
 935   `(let ((inhibit-quit gnus-atomic-be-safe))
 936      ,@forms))
 937
 938 (put 'gnus-atomic-progn 'lisp-indent-function 0)
 939
 940 (defmacro gnus-atomic-progn-assign (protect &rest forms)
 941   "Evaluate FORMS, but ensure that the variables listed in PROTECT
 942 are not changed if anything in FORMS signals an error or otherwise
 943 non-locally exits.  The variables listed in PROTECT are updated atomically.
 944 It is safe to use gnus-atomic-progn-assign with long computations.
 945
 946 Note that if any of the symbols in PROTECT were unbound, they will be
 947 set to nil on a successful assignment.  In case of an error or other
 948 non-local exit, it will still be unbound."
 949   (let* ((temp-sym-map (mapcar (lambda (x) (list (make-symbol
 950                                                   (concat (symbol-name x)
 951                                                           "-tmp"))
 952                                                  x))
 953                                protect))
 954          (sym-temp-map (mapcar (lambda (x) (list (cadr x) (car x)))
 955                                temp-sym-map))
 956          (temp-sym-let (mapcar (lambda (x) (list (car x)
 957                                                  `(and (boundp ',(cadr x))
 958                                                        ,(cadr x))))
 959                                temp-sym-map))
 960          (sym-temp-let sym-temp-map)
 961          (temp-sym-assign (apply 'append temp-sym-map))
 962          (sym-temp-assign (apply 'append sym-temp-map))
 963          (result (make-symbol "result-tmp")))
 964     `(let (,@temp-sym-let
 965            ,result)
 966        (let ,sym-temp-let
 967          (setq ,result (progn ,@forms))
 968          (setq ,@temp-sym-assign))
 969        (let ((inhibit-quit gnus-atomic-be-safe))
 970          (setq ,@sym-temp-assign))
 971        ,result)))
 972
 973 (put 'gnus-atomic-progn-assign 'lisp-indent-function 1)
 974 ;(put 'gnus-atomic-progn-assign 'edebug-form-spec '(sexp body))
 975
 976 (defmacro gnus-atomic-setq (&rest pairs)
 977   "Similar to setq, except that the real symbols are only assigned when
 978 there are no errors.  And when the real symbols are assigned, they are
 979 done so atomically.  If other variables might be changed via side-effect,
 980 see gnus-atomic-progn-assign.  It is safe to use gnus-atomic-setq
 981 with potentially long computations."
 982   (let ((tpairs pairs)
 983         syms)
 984     (while tpairs
 985       (push (car tpairs) syms)
 986       (setq tpairs (cddr tpairs)))
 987     `(gnus-atomic-progn-assign ,syms
 988        (setq ,@pairs))))
 989
 990 ;(put 'gnus-atomic-setq 'edebug-form-spec '(body))
 991
 992
 993 ;;; Functions for saving to babyl/mail files.
 994
 995 (eval-when-compile
 996   (if (featurep 'xemacs)
 997       ;; Don't load tm and apel XEmacs packages that provide some
 998       ;; Emacs emulating functions and variables.
 999       (let ((features features))
1000         (provide 'tm-view)
1001         (unless (fboundp 'set-alist) (defalias 'set-alist 'ignore))
1002         (require 'rmail)) ;; It requires tm-view that loads apel.
1003     (require 'rmail))
1004   (autoload 'rmail-update-summary "rmailsum"))
1005
1006 (defvar mm-text-coding-system)
1007
1008 (declare-function mm-append-to-file "mm-util"
1009                   (start end filename &optional codesys inhibit))
1010
1011 (defun gnus-output-to-rmail (filename &optional ask)
1012   "Append the current article to an Rmail file named FILENAME.
1013 In Emacs 22 this writes Babyl format; in Emacs 23 it writes mbox unless
1014 FILENAME exists and is Babyl format."
1015   (require 'rmail)
1016   (require 'mm-util)
1017   (require 'nnmail)
1018   ;; Some of this codes is borrowed from rmailout.el.
1019   (setq filename (expand-file-name filename))
1020   ;; FIXME should we really be messing with this defcustom?
1021   ;; It is not needed for the operation of this function.
1022   (if (boundp 'rmail-default-rmail-file)
1023       (setq rmail-default-rmail-file filename) ; 22
1024     (setq rmail-default-file filename))        ; 23
1025   (let ((artbuf (current-buffer))
1026         (tmpbuf (get-buffer-create " *Gnus-output*"))
1027         ;; Babyl rmail.el defines this, mbox does not.
1028         (babyl (fboundp 'rmail-insert-rmail-file-header)))
1029     (save-excursion
1030       ;; Note that we ignore the possibility of visiting a Babyl
1031       ;; format buffer in Emacs 23, since Rmail no longer supports that.
1032      (or (get-file-buffer filename)
1033          (progn
1034            ;; In case someone wants to write to a Babyl file from Emacs 23.
1035            (when (file-exists-p filename)
1036              (setq babyl (mail-file-babyl-p filename))
1037              t))
1038           (if (or (not ask)
1039                   (gnus-yes-or-no-p
1040                    (concat "\"" filename "\" does not exist, create it? ")))
1041               (let ((file-buffer (create-file-buffer filename)))
1042                 (with-current-buffer file-buffer
1043                   (if (fboundp 'rmail-insert-rmail-file-header)
1044                       (rmail-insert-rmail-file-header))
1045                   (let ((require-final-newline nil)
1046                         (coding-system-for-write mm-text-coding-system))
1047                     (gnus-write-buffer filename)))
1048                 (kill-buffer file-buffer))
1049             (error "Output file does not exist")))
1050       (set-buffer tmpbuf)
1051       (erase-buffer)
1052       (insert-buffer-substring artbuf)
1053       (if babyl
1054           (gnus-convert-article-to-rmail)
1055         ;; Non-Babyl case copied from gnus-output-to-mail.
1056         (goto-char (point-min))
1057         (if (looking-at "From ")
1058             (forward-line 1)
1059           (insert "From nobody " (current-time-string) "\n"))
1060         (let (case-fold-search)
1061           (while (re-search-forward "^From " nil t)
1062             (beginning-of-line)
1063             (insert ">"))))
1064       ;; Decide whether to append to a file or to an Emacs buffer.
1065       (let ((outbuf (get-file-buffer filename)))
1066         (if (not outbuf)
1067             (progn
1068               (unless babyl             ; from gnus-output-to-mail
1069                 (let ((buffer-read-only nil))
1070                   (goto-char (point-max))
1071                   (forward-char -2)
1072                   (unless (looking-at "\n\n")
1073                     (goto-char (point-max))
1074                     (unless (bolp)
1075                       (insert "\n"))
1076                     (insert "\n"))))
1077               (let ((file-name-coding-system nnmail-pathname-coding-system))
1078                 (mm-append-to-file (point-min) (point-max) filename)))
1079           ;; File has been visited, in buffer OUTBUF.
1080           (set-buffer outbuf)
1081           (let ((buffer-read-only nil)
1082                 (msg (and (boundp 'rmail-current-message)
1083                           (symbol-value 'rmail-current-message))))
1084             ;; If MSG is non-nil, buffer is in RMAIL mode.
1085             ;; Compare this with rmail-output-to-rmail-buffer in Emacs 23.
1086             (when msg
1087               (unless babyl
1088                 (rmail-swap-buffers-maybe)
1089                 (rmail-maybe-set-message-counters))
1090               (widen)
1091               (narrow-to-region (point-max) (point-max)))
1092             (insert-buffer-substring tmpbuf)
1093             (when msg
1094               (when babyl
1095                 (goto-char (point-min))
1096                 (widen)
1097                 (search-backward "\n\^_")
1098                 (narrow-to-region (point) (point-max)))
1099               (rmail-count-new-messages t)
1100               (when (rmail-summary-exists)
1101                 (rmail-select-summary
1102                  (rmail-update-summary)))
1103               (rmail-show-message msg))
1104             (save-buffer)))))
1105     (kill-buffer tmpbuf)))
1106
1107 (defun gnus-output-to-mail (filename &optional ask)
1108   "Append the current article to a mail file named FILENAME."
1109   (require 'nnmail)
1110   (setq filename (expand-file-name filename))
1111   (let ((artbuf (current-buffer))
1112         (tmpbuf (get-buffer-create " *Gnus-output*")))
1113     (save-excursion
1114       ;; Create the file, if it doesn't exist.
1115       (when (and (not (get-file-buffer filename))
1116                  (not (file-exists-p filename)))
1117         (if (or (not ask)
1118                 (gnus-y-or-n-p
1119                  (concat "\"" filename "\" does not exist, create it? ")))
1120             (let ((file-buffer (create-file-buffer filename)))
1121               (with-current-buffer file-buffer
1122                 (let ((require-final-newline nil)
1123                       (coding-system-for-write mm-text-coding-system))
1124                   (gnus-write-buffer filename)))
1125               (kill-buffer file-buffer))
1126           (error "Output file does not exist")))
1127       (set-buffer tmpbuf)
1128       (erase-buffer)
1129       (insert-buffer-substring artbuf)
1130       (goto-char (point-min))
1131       (if (looking-at "From ")
1132           (forward-line 1)
1133         (insert "From nobody " (current-time-string) "\n"))
1134       (let (case-fold-search)
1135         (while (re-search-forward "^From " nil t)
1136           (beginning-of-line)
1137           (insert ">")))
1138       ;; Decide whether to append to a file or to an Emacs buffer.
1139       (let ((outbuf (get-file-buffer filename)))
1140         (if (not outbuf)
1141             (let ((buffer-read-only nil))
1142               (save-excursion
1143                 (goto-char (point-max))
1144                 (forward-char -2)
1145                 (unless (looking-at "\n\n")
1146                   (goto-char (point-max))
1147                   (unless (bolp)
1148                     (insert "\n"))
1149                   (insert "\n"))
1150                 (goto-char (point-max))
1151                 (let ((file-name-coding-system nnmail-pathname-coding-system))
1152                   (mm-append-to-file (point-min) (point-max) filename))))
1153           ;; File has been visited, in buffer OUTBUF.
1154           (set-buffer outbuf)
1155           (let ((buffer-read-only nil))
1156             (goto-char (point-max))
1157             (unless (eobp)
1158               (insert "\n"))
1159             (insert "\n")
1160             (insert-buffer-substring tmpbuf)))))
1161     (kill-buffer tmpbuf)))
1162
1163 (defun gnus-convert-article-to-rmail ()
1164   "Convert article in current buffer to Rmail message format."
1165   (let ((buffer-read-only nil))
1166     ;; Convert article directly into Babyl format.
1167     (goto-char (point-min))
1168     (insert "\^L\n0, unseen,,\n*** EOOH ***\n")
1169     (while (search-forward "\n\^_" nil t) ;single char
1170       (replace-match "\n^_" t t))       ;2 chars: "^" and "_"
1171     (goto-char (point-max))
1172     (insert "\^_")))
1173
1174 (defun gnus-map-function (funs arg)
1175   "Apply the result of the first function in FUNS to the second, and so on.
1176 ARG is passed to the first function."
1177   (while funs
1178     (setq arg (funcall (pop funs) arg)))
1179   arg)
1180
1181 (defun gnus-run-hooks (&rest funcs)
1182   "Does the same as `run-hooks', but saves the current buffer."
1183   (save-current-buffer
1184     (apply 'run-hooks funcs)))
1185
1186 (defun gnus-run-hook-with-args (hook &rest args)
1187   "Does the same as `run-hook-with-args', but saves the current buffer."
1188   (save-current-buffer
1189     (apply 'run-hook-with-args hook args)))
1190
1191 (defun gnus-run-mode-hooks (&rest funcs)
1192   "Run `run-mode-hooks' if it is available, otherwise `run-hooks'.
1193 This function saves the current buffer."
1194   (if (fboundp 'run-mode-hooks)
1195       (save-current-buffer (apply 'run-mode-hooks funcs))
1196     (save-current-buffer (apply 'run-hooks funcs))))
1197
1198 ;;; Various
1199
1200 (defvar gnus-group-buffer)              ; Compiler directive
1201 (defun gnus-alive-p ()
1202   "Say whether Gnus is running or not."
1203   (and (boundp 'gnus-group-buffer)
1204        (get-buffer gnus-group-buffer)
1205        (with-current-buffer gnus-group-buffer
1206          (eq major-mode 'gnus-group-mode))))
1207
1208 (defun gnus-remove-if (predicate sequence &optional hash-table-p)
1209   "Return a copy of SEQUENCE with all items satisfying PREDICATE removed.
1210 SEQUENCE should be a list, a vector, or a string.  Returns always a list.
1211 If HASH-TABLE-P is non-nil, regards SEQUENCE as a hash table."
1212   (let (out)
1213     (if hash-table-p
1214         (mapatoms (lambda (symbol)
1215                     (unless (funcall predicate symbol)
1216                       (push symbol out)))
1217                   sequence)
1218       (unless (listp sequence)
1219         (setq sequence (append sequence nil)))
1220       (while sequence
1221         (unless (funcall predicate (car sequence))
1222           (push (car sequence) out))
1223         (setq sequence (cdr sequence))))
1224     (nreverse out)))
1225
1226 (defun gnus-remove-if-not (predicate sequence &optional hash-table-p)
1227   "Return a copy of SEQUENCE with all items not satisfying PREDICATE removed.
1228 SEQUENCE should be a list, a vector, or a string.  Returns always a list.
1229 If HASH-TABLE-P is non-nil, regards SEQUENCE as a hash table."
1230   (let (out)
1231     (if hash-table-p
1232         (mapatoms (lambda (symbol)
1233                     (when (funcall predicate symbol)
1234                       (push symbol out)))
1235                   sequence)
1236       (unless (listp sequence)
1237         (setq sequence (append sequence nil)))
1238       (while sequence
1239         (when (funcall predicate (car sequence))
1240           (push (car sequence) out))
1241         (setq sequence (cdr sequence))))
1242     (nreverse out)))
1243
1244 (if (fboundp 'assq-delete-all)
1245     (defalias 'gnus-delete-alist 'assq-delete-all)
1246   (defun gnus-delete-alist (key alist)
1247     "Delete from ALIST all elements whose car is KEY.
1248 Return the modified alist."
1249     (let (entry)
1250       (while (setq entry (assq key alist))
1251         (setq alist (delq entry alist)))
1252       alist)))
1253
1254 (defun gnus-grep-in-list (word list)
1255   "Find if a WORD matches any regular expression in the given LIST."
1256   (when (and word list)
1257     (catch 'found
1258       (dolist (r list)
1259         (when (string-match r word)
1260           (throw 'found r))))))
1261
1262 (defmacro gnus-alist-pull (key alist &optional assoc-p)
1263   "Modify ALIST to be without KEY."
1264   (unless (symbolp alist)
1265     (error "Not a symbol: %s" alist))
1266   (let ((fun (if assoc-p 'assoc 'assq)))
1267     `(setq ,alist (delq (,fun ,key ,alist) ,alist))))
1268
1269 (defun gnus-globalify-regexp (re)
1270   "Return a regexp that matches a whole line, if RE matches a part of it."
1271   (concat (unless (string-match "^\\^" re) "^.*")
1272           re
1273           (unless (string-match "\\$$" re) ".*$")))
1274
1275 (defun gnus-set-window-start (&optional point)
1276   "Set the window start to POINT, or (point) if nil."
1277   (let ((win (gnus-get-buffer-window (current-buffer) t)))
1278     (when win
1279       (set-window-start win (or point (point))))))
1280
1281 (defun gnus-annotation-in-region-p (b e)
1282   (if (= b e)
1283       (eq (cadr (memq 'gnus-undeletable (text-properties-at b))) t)
1284     (text-property-any b e 'gnus-undeletable t)))
1285
1286 (defun gnus-or (&rest elems)
1287   "Return non-nil if any of the elements are non-nil."
1288   (catch 'found
1289     (while elems
1290       (when (pop elems)
1291         (throw 'found t)))))
1292
1293 (defun gnus-and (&rest elems)
1294   "Return non-nil if all of the elements are non-nil."
1295   (catch 'found
1296     (while elems
1297       (unless (pop elems)
1298         (throw 'found nil)))
1299     t))
1300
1301 ;; gnus.el requires mm-util.
1302 (declare-function mm-disable-multibyte "mm-util")
1303
1304 (defun gnus-write-active-file (file hashtb &optional full-names)
1305   ;; `coding-system-for-write' should be `raw-text' or equivalent.
1306   (let ((coding-system-for-write nnmail-active-file-coding-system))
1307     (with-temp-file file
1308       ;; The buffer should be in the unibyte mode because group names
1309       ;; are ASCII text or encoded non-ASCII text (i.e., unibyte).
1310       (mm-disable-multibyte)
1311       (mapatoms
1312        (lambda (sym)
1313          (when (and sym
1314                     (boundp sym)
1315                     (symbol-value sym))
1316            (insert (format "%S %d %d y\n"
1317                            (if full-names
1318                                sym
1319                              (intern (gnus-group-real-name (symbol-name sym))))
1320                            (or (cdr (symbol-value sym))
1321                                (car (symbol-value sym)))
1322                            (car (symbol-value sym))))))
1323        hashtb)
1324       (goto-char (point-max))
1325       (while (search-backward "\\." nil t)
1326         (delete-char 1)))))
1327
1328 ;; Fixme: Why not use `with-output-to-temp-buffer'?
1329 (defmacro gnus-with-output-to-file (file &rest body)
1330   (let ((buffer (make-symbol "output-buffer"))
1331         (size (make-symbol "output-buffer-size"))
1332         (leng (make-symbol "output-buffer-length"))
1333         (append (make-symbol "output-buffer-append")))
1334     `(let* ((,size 131072)
1335             (,buffer (make-string ,size 0))
1336             (,leng 0)
1337             (,append nil)
1338             (standard-output
1339              (lambda (c)
1340                (aset ,buffer ,leng c)
1341
1342                (if (= ,size (setq ,leng (1+ ,leng)))
1343                    (progn (write-region ,buffer nil ,file ,append 'no-msg)
1344                           (setq ,leng 0
1345                                 ,append t))))))
1346        ,@body
1347        (when (> ,leng 0)
1348          (let ((coding-system-for-write 'no-conversion))
1349          (write-region (substring ,buffer 0 ,leng) nil ,file
1350                        ,append 'no-msg))))))
1351
1352 (put 'gnus-with-output-to-file 'lisp-indent-function 1)
1353 (put 'gnus-with-output-to-file 'edebug-form-spec '(form body))
1354
1355 (if (fboundp 'union)
1356     (defalias 'gnus-union 'union)
1357   (defun gnus-union (l1 l2)
1358     "Set union of lists L1 and L2."
1359     (cond ((null l1) l2)
1360           ((null l2) l1)
1361           ((equal l1 l2) l1)
1362           (t
1363            (or (>= (length l1) (length l2))
1364                (setq l1 (prog1 l2 (setq l2 l1))))
1365            (while l2
1366              (or (member (car l2) l1)
1367                  (push (car l2) l1))
1368              (pop l2))
1369            l1))))
1370
1371 (declare-function gnus-add-text-properties "gnus"
1372                   (start end properties &optional object))
1373
1374 (defun gnus-add-text-properties-when
1375   (property value start end properties &optional object)
1376   "Like `gnus-add-text-properties', only applied on where PROPERTY is VALUE."
1377   (let (point)
1378     (while (and start
1379                 (< start end) ;; XEmacs will loop for every when start=end.
1380                 (setq point (text-property-not-all start end property value)))
1381       (gnus-add-text-properties start point properties object)
1382       (setq start (text-property-any point end property value)))
1383     (if start
1384         (gnus-add-text-properties start end properties object))))
1385
1386 (defun gnus-remove-text-properties-when
1387   (property value start end properties &optional object)
1388   "Like `remove-text-properties', only applied on where PROPERTY is VALUE."
1389   (let (point)
1390     (while (and start
1391                 (< start end)
1392                 (setq point (text-property-not-all start end property value)))
1393       (remove-text-properties start point properties object)
1394       (setq start (text-property-any point end property value)))
1395     (if start
1396         (remove-text-properties start end properties object))
1397     t))
1398
1399 (defun gnus-string-remove-all-properties (string)
1400   (condition-case ()
1401       (let ((s string))
1402         (set-text-properties 0 (length string) nil string)
1403         s)
1404     (error string)))
1405
1406 ;; This might use `compare-strings' to reduce consing in the
1407 ;; case-insensitive case, but it has to cope with null args.
1408 ;; (`string-equal' uses symbol print names.)
1409 (defun gnus-string-equal (x y)
1410   "Like `string-equal', except it compares case-insensitively."
1411   (and (= (length x) (length y))
1412        (or (string-equal x y)
1413            (string-equal (downcase x) (downcase y)))))
1414
1415 (defcustom gnus-use-byte-compile t
1416   "If non-nil, byte-compile crucial run-time code.
1417 Setting it to nil has no effect after the first time `gnus-byte-compile'
1418 is run."
1419   :type 'boolean
1420   :version "22.1"
1421   :group 'gnus-various)
1422
1423 (defun gnus-byte-compile (form)
1424   "Byte-compile FORM if `gnus-use-byte-compile' is non-nil."
1425   (if gnus-use-byte-compile
1426       (progn
1427         (condition-case nil
1428             ;; Work around a bug in XEmacs 21.4
1429             (require 'byte-optimize)
1430           (error))
1431         (require 'bytecomp)
1432         (defalias 'gnus-byte-compile
1433           (lambda (form)
1434             (let ((byte-compile-warnings '(unresolved callargs redefine)))
1435               (byte-compile form))))
1436         (gnus-byte-compile form))
1437     form))
1438
1439 (defun gnus-remassoc (key alist)
1440   "Delete by side effect any elements of LIST whose car is `equal' to KEY.
1441 The modified LIST is returned.  If the first member
1442 of LIST has a car that is `equal' to KEY, there is no way to remove it
1443 by side effect; therefore, write `(setq foo (gnus-remassoc key foo))' to be
1444 sure of changing the value of `foo'."
1445   (when alist
1446     (if (equal key (caar alist))
1447         (cdr alist)
1448       (setcdr alist (gnus-remassoc key (cdr alist)))
1449       alist)))
1450
1451 (defun gnus-update-alist-soft (key value alist)
1452   (if value
1453       (cons (cons key value) (gnus-remassoc key alist))
1454     (gnus-remassoc key alist)))
1455
1456 (defun gnus-create-info-command (node)
1457   "Create a command that will go to info NODE."
1458   `(lambda ()
1459      (interactive)
1460      ,(concat "Enter the info system at node " node)
1461      (Info-goto-node ,node)
1462      (setq gnus-info-buffer (current-buffer))
1463      (gnus-configure-windows 'info)))
1464
1465 (defun gnus-not-ignore (&rest args)
1466   t)
1467
1468 (defvar gnus-directory-sep-char-regexp "/"
1469   "The regexp of directory separator character.
1470 If you find some problem with the directory separator character, try
1471 \"[/\\\\\]\" for some systems.")
1472
1473 (defun gnus-url-unhex (x)
1474   (if (> x ?9)
1475       (if (>= x ?a)
1476           (+ 10 (- x ?a))
1477         (+ 10 (- x ?A)))
1478     (- x ?0)))
1479
1480 ;; Fixme: Do it like QP.
1481 (defun gnus-url-unhex-string (str &optional allow-newlines)
1482   "Remove %XX, embedded spaces, etc in a url.
1483 If optional second argument ALLOW-NEWLINES is non-nil, then allow the
1484 decoding of carriage returns and line feeds in the string, which is normally
1485 forbidden in URL encoding."
1486   (let ((tmp "")
1487         (case-fold-search t))
1488     (while (string-match "%[0-9a-f][0-9a-f]" str)
1489       (let* ((start (match-beginning 0))
1490              (ch1 (gnus-url-unhex (elt str (+ start 1))))
1491              (code (+ (* 16 ch1)
1492                       (gnus-url-unhex (elt str (+ start 2))))))
1493         (setq tmp (concat
1494                    tmp (substring str 0 start)
1495                    (cond
1496                     (allow-newlines
1497                      (char-to-string code))
1498                     ((or (= code ?\n) (= code ?\r))
1499                      " ")
1500                     (t (char-to-string code))))
1501               str (substring str (match-end 0)))))
1502     (setq tmp (concat tmp str))
1503     tmp))
1504
1505 (defun gnus-make-predicate (spec)
1506   "Transform SPEC into a function that can be called.
1507 SPEC is a predicate specifier that contains stuff like `or', `and',
1508 `not', lists and functions.  The functions all take one parameter."
1509   `(lambda (elem) ,(gnus-make-predicate-1 spec)))
1510
1511 (defun gnus-make-predicate-1 (spec)
1512   (cond
1513    ((symbolp spec)
1514     `(,spec elem))
1515    ((listp spec)
1516     (if (memq (car spec) '(or and not))
1517         `(,(car spec) ,@(mapcar 'gnus-make-predicate-1 (cdr spec)))
1518       (error "Invalid predicate specifier: %s" spec)))))
1519
1520 (defun gnus-completing-read (prompt collection &optional require-match
1521                                     initial-input history def)
1522   "Call `gnus-completing-read-function'."
1523   (funcall gnus-completing-read-function
1524            (concat prompt (when def
1525                             (concat " (default " def ")"))
1526                    ": ")
1527            collection require-match initial-input history def))
1528
1529 (defun gnus-emacs-completing-read (prompt collection &optional require-match
1530                                           initial-input history def)
1531   "Call standard `completing-read-function'."
1532   (let ((completion-styles gnus-completion-styles))
1533     (completing-read prompt
1534                      ;; Old XEmacs (at least 21.4) expect an alist for
1535                      ;; collection.
1536                      (mapcar 'list collection)
1537                      nil require-match initial-input history def)))
1538
1539 (autoload 'ido-completing-read "ido")
1540 (defun gnus-ido-completing-read (prompt collection &optional require-match
1541                                         initial-input history def)
1542   "Call `ido-completing-read-function'."
1543   (ido-completing-read prompt collection nil require-match
1544                        initial-input history def))
1545
1546
1547 (declare-function iswitchb-read-buffer "iswitchb"
1548                   (prompt &optional default require-match start matches-set))
1549 (defvar iswitchb-temp-buflist)
1550
1551 (defun gnus-iswitchb-completing-read (prompt collection &optional require-match
1552                                             initial-input history def)
1553   "`iswitchb' based completing-read function."
1554   ;; Make sure iswitchb is loaded before we let-bind its variables.
1555   ;; If it is loaded inside the let, variables can become unbound afterwards.
1556   (require 'iswitchb)
1557   (let ((iswitchb-make-buflist-hook
1558          (lambda ()
1559            (setq iswitchb-temp-buflist
1560                  (let ((choices (append
1561                                  (when initial-input (list initial-input))
1562                                  (symbol-value history) collection))
1563                        filtered-choices)
1564                    (dolist (x choices)
1565                      (setq filtered-choices (adjoin x filtered-choices)))
1566                    (nreverse filtered-choices))))))
1567     (unwind-protect
1568         (progn
1569           (or iswitchb-mode
1570               (add-hook 'minibuffer-setup-hook 'iswitchb-minibuffer-setup))
1571           (iswitchb-read-buffer prompt def require-match))
1572       (or iswitchb-mode
1573           (remove-hook 'minibuffer-setup-hook 'iswitchb-minibuffer-setup)))))
1574
1575 (defun gnus-graphic-display-p ()
1576   (if (featurep 'xemacs)
1577       (device-on-window-system-p)
1578     (display-graphic-p)))
1579
1580 (put 'gnus-parse-without-error 'lisp-indent-function 0)
1581 (put 'gnus-parse-without-error 'edebug-form-spec '(body))
1582
1583 (defmacro gnus-parse-without-error (&rest body)
1584   "Allow continuing onto the next line even if an error occurs."
1585   `(while (not (eobp))
1586      (condition-case ()
1587          (progn
1588            ,@body
1589            (goto-char (point-max)))
1590        (error
1591         (gnus-error 4 "Invalid data on line %d"
1592                     (count-lines (point-min) (point)))
1593         (forward-line 1)))))
1594
1595 (defun gnus-cache-file-contents (file variable function)
1596   "Cache the contents of FILE in VARIABLE.  The contents come from FUNCTION."
1597   (let ((time (nth 5 (file-attributes file)))
1598         contents value)
1599     (if (or (null (setq value (symbol-value variable)))
1600             (not (equal (car value) file))
1601             (not (equal (nth 1 value) time)))
1602         (progn
1603           (setq contents (funcall function file))
1604           (set variable (list file time contents))
1605           contents)
1606       (nth 2 value))))
1607
1608 (defun gnus-multiple-choice (prompt choice &optional idx)
1609   "Ask user a multiple choice question.
1610 CHOICE is a list of the choice char and help message at IDX."
1611   (let (tchar buf)
1612     (save-window-excursion
1613       (save-excursion
1614         (while (not tchar)
1615           (message "%s (%s): "
1616                    prompt
1617                    (concat
1618                     (mapconcat (lambda (s) (char-to-string (car s)))
1619                                choice ", ") ", ?"))
1620           (setq tchar (read-char))
1621           (when (not (assq tchar choice))
1622             (setq tchar nil)
1623             (setq buf (get-buffer-create "*Gnus Help*"))
1624             (pop-to-buffer buf)
1625             (fundamental-mode)          ; for Emacs 20.4+
1626             (buffer-disable-undo)
1627             (erase-buffer)
1628             (insert prompt ":\n\n")
1629             (let ((max -1)
1630                   (list choice)
1631                   (alist choice)
1632                   (idx (or idx 1))
1633                   (i 0)
1634                   n width pad format)
1635               ;; find the longest string to display
1636               (while list
1637                 (setq n (length (nth idx (car list))))
1638                 (unless (> max n)
1639                   (setq max n))
1640                 (setq list (cdr list)))
1641               (setq max (+ max 4))      ; %c, `:', SPACE, a SPACE at end
1642               (setq n (/ (1- (window-width)) max)) ; items per line
1643               (setq width (/ (1- (window-width)) n)) ; width of each item
1644               ;; insert `n' items, each in a field of width `width'
1645               (while alist
1646                 (if (< i n)
1647                     ()
1648                   (setq i 0)
1649                   (delete-char -1)              ; the `\n' takes a char
1650                   (insert "\n"))
1651                 (setq pad (- width 3))
1652                 (setq format (concat "%c: %-" (int-to-string pad) "s"))
1653                 (insert (format format (caar alist) (nth idx (car alist))))
1654                 (setq alist (cdr alist))
1655                 (setq i (1+ i))))))))
1656     (if (buffer-live-p buf)
1657         (kill-buffer buf))
1658     tchar))
1659
1660 (if (featurep 'emacs)
1661     (defalias 'gnus-select-frame-set-input-focus 'select-frame-set-input-focus)
1662   (if (fboundp 'select-frame-set-input-focus)
1663       (defalias 'gnus-select-frame-set-input-focus 'select-frame-set-input-focus)
1664     ;; XEmacs 21.4, SXEmacs
1665     (defun gnus-select-frame-set-input-focus (frame)
1666       "Select FRAME, raise it, and set input focus, if possible."
1667       (raise-frame frame)
1668       (select-frame frame)
1669       (focus-frame frame))))
1670
1671 (defun gnus-frame-or-window-display-name (object)
1672   "Given a frame or window, return the associated display name.
1673 Return nil otherwise."
1674   (if (featurep 'xemacs)
1675       (device-connection (dfw-device object))
1676     (if (or (framep object)
1677             (and (windowp object)
1678                  (setq object (window-frame object))))
1679         (let ((display (frame-parameter object 'display)))
1680           (if (and (stringp display)
1681                    ;; Exclude invalid display names.
1682                    (string-match "\\`[^:]*:[0-9]+\\(\\.[0-9]+\\)?\\'"
1683                                  display))
1684               display)))))
1685
1686 (defvar tool-bar-mode)
1687
1688 (defun gnus-tool-bar-update (&rest ignore)
1689   "Update the tool bar."
1690   (when (and (boundp 'tool-bar-mode)
1691              tool-bar-mode)
1692     (let* ((args nil)
1693            (func (cond ((featurep 'xemacs)
1694                         'ignore)
1695                        ((fboundp 'tool-bar-update)
1696                         'tool-bar-update)
1697                        ((fboundp 'force-window-update)
1698                         'force-window-update)
1699                        ((fboundp 'redraw-frame)
1700                         (setq args (list (selected-frame)))
1701                         'redraw-frame)
1702                        (t 'ignore))))
1703       (apply func args))))
1704
1705 ;; Fixme: This has only one use (in gnus-agent), which isn't worthwhile.
1706 (defmacro gnus-mapcar (function seq1 &rest seqs2_n)
1707   "Apply FUNCTION to each element of the sequences, and make a list of the results.
1708 If there are several sequences, FUNCTION is called with that many arguments,
1709 and mapping stops as soon as the shortest sequence runs out.  With just one
1710 sequence, this is like `mapcar'.  With several, it is like the Common Lisp
1711 `mapcar' function extended to arbitrary sequence types."
1712
1713   (if seqs2_n
1714       (let* ((seqs (cons seq1 seqs2_n))
1715              (cnt 0)
1716              (heads (mapcar (lambda (seq)
1717                               (make-symbol (concat "head"
1718                                                    (int-to-string
1719                                                     (setq cnt (1+ cnt))))))
1720                             seqs))
1721              (result (make-symbol "result"))
1722              (result-tail (make-symbol "result-tail")))
1723         `(let* ,(let* ((bindings (cons nil nil))
1724                        (heads heads))
1725                   (nconc bindings (list (list result '(cons nil nil))))
1726                   (nconc bindings (list (list result-tail result)))
1727                   (while heads
1728                     (nconc bindings (list (list (pop heads) (pop seqs)))))
1729                   (cdr bindings))
1730            (while (and ,@heads)
1731              (setcdr ,result-tail (cons (funcall ,function
1732                                                  ,@(mapcar (lambda (h) (list 'car h))
1733                                                            heads))
1734                                         nil))
1735              (setq ,result-tail (cdr ,result-tail)
1736                    ,@(apply 'nconc (mapcar (lambda (h) (list h (list 'cdr h))) heads))))
1737            (cdr ,result)))
1738     `(mapcar ,function ,seq1)))
1739
1740 (if (fboundp 'merge)
1741     (defalias 'gnus-merge 'merge)
1742   ;; Adapted from cl-seq.el
1743   (defun gnus-merge (type list1 list2 pred)
1744     "Destructively merge lists LIST1 and LIST2 to produce a new list.
1745 Argument TYPE is for compatibility and ignored.
1746 Ordering of the elements is preserved according to PRED, a `less-than'
1747 predicate on the elements."
1748     (let ((res nil))
1749       (while (and list1 list2)
1750         (if (funcall pred (car list2) (car list1))
1751             (push (pop list2) res)
1752           (push (pop list1) res)))
1753       (nconc (nreverse res) list1 list2))))
1754
1755 (defvar xemacs-codename)
1756 (defvar sxemacs-codename)
1757 (defvar emacs-program-version)
1758
1759 (defun gnus-emacs-version ()
1760   "Stringified Emacs version."
1761   (let* ((lst (if (listp gnus-user-agent)
1762                   gnus-user-agent
1763                 '(gnus emacs type)))
1764          (system-v (cond ((memq 'config lst)
1765                           system-configuration)
1766                          ((memq 'type lst)
1767                           (symbol-name system-type))
1768                          (t nil)))
1769          codename emacsname)
1770     (cond ((featurep 'sxemacs)
1771            (setq emacsname "SXEmacs"
1772                  codename sxemacs-codename))
1773           ((featurep 'xemacs)
1774            (setq emacsname "XEmacs"
1775                  codename xemacs-codename))
1776           (t
1777            (setq emacsname "Emacs")))
1778     (cond
1779      ((not (memq 'emacs lst))
1780       nil)
1781      ((string-match "^\\(\\([.0-9]+\\)*\\)\\.[0-9]+$" emacs-version)
1782       ;; Emacs:
1783       (concat "Emacs/" (match-string 1 emacs-version)
1784               (if system-v
1785                   (concat " (" system-v ")")
1786                 "")))
1787      ((or (featurep 'sxemacs) (featurep 'xemacs))
1788       ;; XEmacs or SXEmacs:
1789       (concat emacsname "/" emacs-program-version
1790               (let (plst)
1791                 (when (memq 'codename lst)
1792                   (push codename plst))
1793                 (when system-v
1794                   (push system-v plst))
1795                 (unless (featurep 'mule)
1796                   (push "no MULE" plst))
1797                 (when (> (length plst) 0)
1798                   (concat
1799                    " (" (mapconcat 'identity (reverse plst) ", ") ")")))))
1800      (t emacs-version))))
1801
1802 (defun gnus-rename-file (old-path new-path &optional trim)
1803   "Rename OLD-PATH as NEW-PATH.  If TRIM, recursively delete
1804 empty directories from OLD-PATH."
1805   (when (file-exists-p old-path)
1806     (let* ((old-dir (file-name-directory old-path))
1807            (old-name (file-name-nondirectory old-path))
1808            (new-dir (file-name-directory new-path))
1809            (new-name (file-name-nondirectory new-path))
1810            temp)
1811       (gnus-make-directory new-dir)
1812       (rename-file old-path new-path t)
1813       (when trim
1814         (while (progn (setq temp (directory-files old-dir))
1815                       (while (member (car temp) '("." ".."))
1816                         (setq temp (cdr temp)))
1817                       (= (length temp) 0))
1818           (delete-directory old-dir)
1819           (setq old-dir (file-name-as-directory
1820                          (file-truename
1821                           (concat old-dir "..")))))))))
1822
1823 (defun gnus-set-file-modes (filename mode)
1824   "Wrapper for set-file-modes."
1825   (ignore-errors
1826     (set-file-modes filename mode)))
1827
1828 (if (fboundp 'set-process-query-on-exit-flag)
1829     (defalias 'gnus-set-process-query-on-exit-flag
1830       'set-process-query-on-exit-flag)
1831   (defalias 'gnus-set-process-query-on-exit-flag
1832     'process-kill-without-query))
1833
1834 (defalias 'gnus-read-shell-command
1835   (if (fboundp 'read-shell-command) 'read-shell-command 'read-string))
1836
1837 (defmacro gnus-put-display-table (range value display-table)
1838   "Set the value for char RANGE to VALUE in DISPLAY-TABLE.  "
1839   (if (featurep 'xemacs)
1840       (progn
1841         `(if (fboundp 'put-display-table)
1842           (put-display-table ,range ,value ,display-table)
1843           (if (sequencep ,display-table)
1844               (aset ,display-table ,range ,value)
1845             (put-char-table ,range ,value ,display-table))))
1846     `(aset ,display-table ,range ,value)))
1847
1848 (defmacro gnus-get-display-table (character display-table)
1849   "Find value for CHARACTER in DISPLAY-TABLE.  "
1850   (if (featurep 'xemacs)
1851       `(if (fboundp 'get-display-table)
1852           (get-display-table ,character ,display-table)
1853           (if (sequencep ,display-table)
1854               (aref ,display-table ,character)
1855             (get-char-table ,character ,display-table)))
1856     `(aref ,display-table ,character)))
1857
1858 (defun gnus-rescale-image (image size)
1859   "Rescale IMAGE to SIZE if possible.
1860 SIZE is in format (WIDTH . HEIGHT). Return a new image.
1861 Sizes are in pixels."
1862   (if (or (not (fboundp 'imagemagick-types))
1863           (not (get-buffer-window (current-buffer))))
1864       image
1865     (let ((new-width (car size))
1866           (new-height (cdr size)))
1867       (when (> (cdr (image-size image t)) new-height)
1868         (setq image (or (create-image (plist-get (cdr image) :data) 'imagemagick t
1869                                       :height new-height)
1870                         image)))
1871       (when (> (car (image-size image t)) new-width)
1872         (setq image (or
1873                    (create-image (plist-get (cdr image) :data) 'imagemagick t
1874                                  :width new-width)
1875                    image)))
1876       image)))
1877
1878 (defun gnus-recursive-directory-files (dir)
1879   "Return all regular files below DIR."
1880   (let (files)
1881     (dolist (file (directory-files dir t))
1882       (when (and (not (member (file-name-nondirectory file) '("." "..")))
1883                  (file-readable-p file))
1884         (cond
1885          ((file-regular-p file)
1886           (push file files))
1887          ((file-directory-p file)
1888           (setq files (append (gnus-recursive-directory-files file) files))))))
1889     files))
1890
1891 (defun gnus-list-memq-of-list (elements list)
1892   "Return non-nil if any of the members of ELEMENTS are in LIST."
1893   (let ((found nil))
1894     (dolist (elem elements)
1895       (setq found (or found
1896                       (memq elem list))))
1897     found))
1898
1899 (eval-and-compile
1900   (cond
1901    ((fboundp 'match-substitute-replacement)
1902     (defalias 'gnus-match-substitute-replacement 'match-substitute-replacement))
1903    (t
1904     (defun gnus-match-substitute-replacement (replacement &optional fixedcase literal string subexp)
1905       "Return REPLACEMENT as it will be inserted by `replace-match'.
1906 In other words, all back-references in the form `\\&' and `\\N'
1907 are substituted with actual strings matched by the last search.
1908 Optional FIXEDCASE, LITERAL, STRING and SUBEXP have the same
1909 meaning as for `replace-match'.
1910
1911 This is the definition of match-substitute-replacement in subr.el from GNU Emacs."
1912       (let ((match (match-string 0 string)))
1913         (save-match-data
1914           (set-match-data (mapcar (lambda (x)
1915                                     (if (numberp x)
1916                                         (- x (match-beginning 0))
1917                                       x))
1918                                   (match-data t)))
1919           (replace-match replacement fixedcase literal match subexp)))))))
1920
1921 (if (fboundp 'string-match-p)
1922     (defalias 'gnus-string-match-p 'string-match-p)
1923   (defsubst gnus-string-match-p (regexp string &optional start)
1924     "\
1925 Same as `string-match' except this function does not change the match data."
1926     (save-match-data
1927       (string-match regexp string start))))
1928
1929 (if (fboundp 'string-prefix-p)
1930     (defalias 'gnus-string-prefix-p 'string-prefix-p)
1931   (defun gnus-string-prefix-p (str1 str2 &optional ignore-case)
1932     "Return non-nil if STR1 is a prefix of STR2.
1933 If IGNORE-CASE is non-nil, the comparison is done without paying attention
1934 to case differences."
1935     (and (<= (length str1) (length str2))
1936          (let ((prefix (substring str2 0 (length str1))))
1937            (if ignore-case
1938                (string-equal (downcase str1) (downcase prefix))
1939              (string-equal str1 prefix))))))
1940
1941 (eval-and-compile
1942   (if (fboundp 'macroexpand-all)
1943       (defalias 'gnus-macroexpand-all 'macroexpand-all)
1944     (defun gnus-macroexpand-all (form &optional environment)
1945       "Return result of expanding macros at all levels in FORM.
1946 If no macros are expanded, FORM is returned unchanged.
1947 The second optional arg ENVIRONMENT specifies an environment of macro
1948 definitions to shadow the loaded ones for use in file byte-compilation."
1949       (if (consp form)
1950           (let ((idx 1)
1951                 (len (length (setq form (copy-sequence form))))
1952                 expanded)
1953             (while (< idx len)
1954               (setcar (nthcdr idx form) (gnus-macroexpand-all (nth idx form)
1955                                                               environment))
1956               (setq idx (1+ idx)))
1957             (if (eq (setq expanded (macroexpand form environment)) form)
1958                 form
1959               (gnus-macroexpand-all expanded environment)))
1960         form))))
1961
1962 ;; Simple check: can be a macro but this way, although slow, it's really clear.
1963 ;; We don't use `bound-and-true-p' because it's not in XEmacs.
1964 (defun gnus-bound-and-true-p (sym)
1965   (and (boundp sym) (symbol-value sym)))
1966
1967 (if (fboundp 'timer--function)
1968     (defalias 'gnus-timer--function 'timer--function)
1969   (defun gnus-timer--function (timer)
1970     (elt timer 5)))
1971
1972 (provide 'gnus-util)
1973
1974 ;;; gnus-util.el ends here