1 ;;; disp-table.el --- functions for dealing with char tables
3 ;; Copyright (C) 1987, 1994-1995, 1999, 2001-2015 Free Software
6 ;; Author: Erik Naggum <erik@naggum.no>
7 ;; Based on a previous version by Howard Gayle
8 ;; Maintainer: emacs-devel@gnu.org
12 ;; This file is part of GNU Emacs.
14 ;; GNU Emacs is free software: you can redistribute it and/or modify
15 ;; it under the terms of the GNU General Public License as published by
16 ;; the Free Software Foundation, either version 3 of the License, or
17 ;; (at your option) any later version.
19 ;; GNU Emacs is distributed in the hope that it will be useful,
20 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
21 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 ;; GNU General Public License for more details.
24 ;; You should have received a copy of the GNU General Public License
25 ;; along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>.
31 (put 'display-table
'char-table-extra-slots
6)
34 (defun make-display-table ()
35 "Return a new, empty display table."
36 (make-char-table 'display-table nil
))
38 (or standard-display-table
39 (setq standard-display-table
(make-display-table)))
41 ;;; Display-table slot names. The property value says which slot.
43 (put 'truncation
'display-table-slot
0)
44 (put 'wrap
'display-table-slot
1)
45 (put 'escape
'display-table-slot
2)
46 (put 'control
'display-table-slot
3)
47 (put 'selective-display
'display-table-slot
4)
48 (put 'vertical-border
'display-table-slot
5)
51 (defun display-table-slot (display-table slot
)
52 "Return the value of the extra slot in DISPLAY-TABLE named SLOT.
53 SLOT may be a number from 0 to 5 inclusive, or a slot name (symbol).
54 Valid symbols are `truncation', `wrap', `escape', `control',
55 `selective-display', and `vertical-border'."
57 (if (numberp slot
) slot
58 (or (get slot
'display-table-slot
)
59 (error "Invalid display-table slot name: %s" slot
)))))
60 (char-table-extra-slot display-table slot-number
)))
63 (defun set-display-table-slot (display-table slot value
)
64 "Set the value of the extra slot in DISPLAY-TABLE named SLOT to VALUE.
65 SLOT may be a number from 0 to 5 inclusive, or a name (symbol).
66 Valid symbols are `truncation', `wrap', `escape', `control',
67 `selective-display', and `vertical-border'."
69 (if (numberp slot
) slot
70 (or (get slot
'display-table-slot
)
71 (error "Invalid display-table slot name: %s" slot
)))))
72 (set-char-table-extra-slot display-table slot-number value
)))
75 (defun describe-display-table (dt)
76 "Describe the display table DT in a help buffer."
77 (with-help-window "*Help*"
78 (princ "\nTruncation glyph: ")
79 (prin1 (display-table-slot dt
'truncation
))
80 (princ "\nWrap glyph: ")
81 (prin1 (display-table-slot dt
'wrap
))
82 (princ "\nEscape glyph: ")
83 (prin1 (display-table-slot dt
'escape
))
84 (princ "\nCtrl glyph: ")
85 (prin1 (display-table-slot dt
'control
))
86 (princ "\nSelective display glyph sequence: ")
87 (prin1 (display-table-slot dt
'selective-display
))
88 (princ "\nVertical window border glyph: ")
89 (prin1 (display-table-slot dt
'vertical-border
))
90 (princ "\nCharacter display glyph sequences:\n")
91 (with-current-buffer standard-output
92 (let ((vector (make-vector 256 nil
))
95 (aset vector i
(aref dt i
))
98 vector
'display-table-print-array
))
101 (defun display-table-print-array (desc)
103 (let ((column (current-column))
104 (width (window-width))
106 (dotimes (i (length desc
))
107 (setq string
(format "%s" (aref desc i
)))
109 ((>= (+ (current-column) (length string
) 1)
112 (insert (make-string column ?
)))
119 (defun describe-current-display-table ()
120 "Describe the display table in use in the selected window and buffer."
122 (let ((disptab (or (window-display-table)
124 standard-display-table
)))
126 (describe-display-table disptab
)
127 (message "No display table"))))
130 (defun standard-display-8bit (l h
)
131 "Display characters representing raw bytes in the range L to H literally.
133 On a terminal display, each character in the range is displayed
134 by sending the corresponding byte directly to the terminal.
136 On a graphic display, each character in the range is displayed
137 using the default font by a glyph whose code is the corresponding
140 Note that ASCII printable characters (SPC to TILDA) are displayed
141 in the default way after this call."
142 (or standard-display-table
143 (setq standard-display-table
(make-display-table)))
148 (aset standard-display-table l
149 (if (or (< l ?\s
) (= l
127)) (vector l
)))
150 (let ((c (unibyte-char-to-multibyte l
)))
151 (aset standard-display-table c
(vector c
))))
155 (defun standard-display-default (l h
)
156 "Display characters in the range L to H using the default notation."
157 (or standard-display-table
158 (setq standard-display-table
(make-display-table)))
160 (if (and (>= l ?\s
) (characterp l
))
161 (aset standard-display-table l nil
))
164 ;; This function does NOT take terminal-dependent escape sequences.
165 ;; For that, you need to go through create-glyph. Use one of the
166 ;; other functions below, or roll your own.
168 (defun standard-display-ascii (c s
)
169 "Display character C using printable string S."
170 (or standard-display-table
171 (setq standard-display-table
(make-display-table)))
172 (aset standard-display-table c
(vconcat s
)))
175 (defun standard-display-g1 (c sc
)
176 "Display character C as character SC in the g1 character set.
177 This function assumes that your terminal uses the SO/SI characters;
178 it is meaningless for an X frame."
179 (if (memq window-system
'(x w32 ns
))
180 (error "Cannot use string glyphs in a windowing system"))
181 (or standard-display-table
182 (setq standard-display-table
(make-display-table)))
183 (aset standard-display-table c
184 (vector (create-glyph (concat "\016" (char-to-string sc
) "\017")))))
187 (defun standard-display-graphic (c gc
)
188 "Display character C as character GC in graphics character set.
189 This function assumes VT100-compatible escapes; it is meaningless for an
191 (if (memq window-system
'(x w32 ns
))
192 (error "Cannot use string glyphs in a windowing system"))
193 (or standard-display-table
194 (setq standard-display-table
(make-display-table)))
195 (aset standard-display-table c
196 (vector (create-glyph (concat "\e(0" (char-to-string gc
) "\e(B")))))
199 (defun standard-display-underline (c uc
)
200 "Display character C as character UC plus underlining."
201 (or standard-display-table
202 (setq standard-display-table
(make-display-table)))
203 (aset standard-display-table c
206 (make-glyph-code uc
'underline
)
207 (create-glyph (concat "\e[4m" (char-to-string uc
) "\e[m"))))))
210 (defun create-glyph (string)
211 "Allocate a glyph code to display by sending STRING to the terminal."
212 (if (= (length glyph-table
) 65536)
213 (error "No free glyph codes remain"))
214 ;; Don't use slots that correspond to ASCII characters.
215 (if (= (length glyph-table
) 32)
216 (setq glyph-table
(vconcat glyph-table
(make-vector 224 nil
))))
217 (setq glyph-table
(vconcat glyph-table
(list string
)))
218 (1- (length glyph-table
)))
221 (defun make-glyph-code (char &optional face
)
222 "Return a glyph code representing char CHAR with face FACE."
223 ;; Due to limitations on Emacs integer values, faces with
224 ;; face id greater that 512 are silently ignored.
227 (let ((fid (face-id face
)))
228 (if (< fid
64) ; we have 32 - 3(LSB) - 1(SIGN) - 22(CHAR) = 6 bits for face id
229 (logior char
(lsh fid
22))
233 (defun glyph-char (glyph)
234 "Return the character of glyph code GLYPH."
237 (logand glyph
#x3fffff
)))
240 (defun glyph-face (glyph)
241 "Return the face of glyph code GLYPH, or nil if glyph has default face."
242 (let ((face-id (if (consp glyph
) (cdr glyph
) (lsh glyph -
22))))
245 (dolist (face (face-list))
246 (when (eq (face-id face
) face-id
)
247 (throw 'face face
)))))))
250 (defun standard-display-european (arg)
251 "Semi-obsolete way to toggle display of ISO 8859 European characters.
253 This function is semi-obsolete; you probably don't need it, or else you
254 probably should use `set-language-environment' or `set-locale-environment'.
256 This function enables European character display if ARG is positive,
257 disables it if negative. Otherwise, it toggles European character display.
259 When this mode is enabled, characters in the range of 160 to 255
260 display not as octal escapes, but as accented characters. Codes 146
261 and 160 display as apostrophe and space, even though they are not the
262 ASCII codes for apostrophe and space.
264 Enabling European character display with this command noninteractively
265 from Lisp code also selects Latin-1 as the language environment.
266 This provides increased compatibility for users who call this function
269 (if (or (<= (prefix-numeric-value arg
) 0)
271 (char-table-p standard-display-table
)
272 ;; Test 161, because 160 displays as a space.
273 (equal (aref standard-display-table
274 (unibyte-char-to-multibyte 161))
275 (vector (unibyte-char-to-multibyte 161)))))
277 (standard-display-default
278 (unibyte-char-to-multibyte 160) (unibyte-char-to-multibyte 255))
279 (unless (or (memq window-system
'(x w32 ns
)))
280 (and (terminal-coding-system)
281 (set-terminal-coding-system nil
))))
283 (display-warning 'i18n
285 "`standard-display-european' is semi-obsolete; see its doc string for details")
288 ;; Switch to Latin-1 language environment
289 ;; unless some other has been specified.
290 (if (equal current-language-environment
"English")
291 (set-language-environment "latin-1"))
292 (unless (or noninteractive
(memq window-system
'(x w32 ns
)))
293 ;; Send those codes literally to a character-based terminal.
294 ;; If we are using single-byte characters,
295 ;; it doesn't matter which coding system we use.
296 (set-terminal-coding-system
297 (let ((c (intern (downcase current-language-environment
))))
298 (if (coding-system-p c
) c
'latin-1
))))
299 (standard-display-european-internal)))
301 (provide 'disp-table
)
303 ;;; disp-table.el ends here