1 /* Indentation functions.
2 Copyright (C) 1985, 1986, 1987, 1988, 1993, 1994, 1995, 1998, 2000, 2001,
3 2002, 2003, 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
5 This file is part of GNU Emacs.
7 GNU Emacs is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
12 GNU Emacs is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GNU Emacs; see the file COPYING. If not, write to
19 the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
20 Boston, MA 02110-1301, USA. */
34 #include "intervals.h"
35 #include "region-cache.h"
37 /* Indentation can insert tabs if this is non-zero;
38 otherwise always uses spaces. */
44 /* These three values memorize the current column to avoid recalculation. */
46 /* Last value returned by current_column.
47 Some things in set last_known_column_point to -1
48 to mark the memorized value as invalid. */
50 double last_known_column
;
52 /* Value of point when current_column was called. */
54 int last_known_column_point
;
56 /* Value of MODIFF when current_column was called. */
58 int last_known_column_modified
;
60 static double current_column_1
P_ ((void));
61 static double position_indentation
P_ ((int));
63 /* Cache of beginning of line found by the last call of
66 int current_column_bol_cache
;
68 /* Get the display table to use for the current buffer. */
70 struct Lisp_Char_Table
*
71 buffer_display_table ()
75 thisbuf
= current_buffer
->display_table
;
76 if (DISP_TABLE_P (thisbuf
))
77 return XCHAR_TABLE (thisbuf
);
78 if (DISP_TABLE_P (Vstandard_display_table
))
79 return XCHAR_TABLE (Vstandard_display_table
);
83 /* Width run cache considerations. */
85 /* Return the width of character C under display table DP. */
88 character_width (c
, dp
)
90 struct Lisp_Char_Table
*dp
;
94 /* These width computations were determined by examining the cases
95 in display_text_line. */
97 /* Everything can be handled by the display table, if it's
98 present and the element is right. */
99 if (dp
&& (elt
= DISP_CHAR_VECTOR (dp
, c
), VECTORP (elt
)))
100 return XVECTOR (elt
)->size
;
102 /* Some characters are special. */
103 if (c
== '\n' || c
== '\t' || c
== '\015')
106 /* Printing characters have width 1. */
107 else if (c
>= 040 && c
< 0177)
110 /* Everybody else (control characters, metacharacters) has other
111 widths. We could return their actual widths here, but they
112 depend on things like ctl_arrow and crud like that, and they're
113 not very common at all. So we'll just claim we don't know their
119 /* Return true iff the display table DISPTAB specifies the same widths
120 for characters as WIDTHTAB. We use this to decide when to
121 invalidate the buffer's width_run_cache. */
124 disptab_matches_widthtab (disptab
, widthtab
)
125 struct Lisp_Char_Table
*disptab
;
126 struct Lisp_Vector
*widthtab
;
130 if (widthtab
->size
!= 256)
133 for (i
= 0; i
< 256; i
++)
134 if (character_width (i
, disptab
)
135 != XFASTINT (widthtab
->contents
[i
]))
141 /* Recompute BUF's width table, using the display table DISPTAB. */
144 recompute_width_table (buf
, disptab
)
146 struct Lisp_Char_Table
*disptab
;
149 struct Lisp_Vector
*widthtab
;
151 if (!VECTORP (buf
->width_table
))
152 buf
->width_table
= Fmake_vector (make_number (256), make_number (0));
153 widthtab
= XVECTOR (buf
->width_table
);
154 if (widthtab
->size
!= 256)
157 for (i
= 0; i
< 256; i
++)
158 XSETFASTINT (widthtab
->contents
[i
], character_width (i
, disptab
));
161 /* Allocate or free the width run cache, as requested by the current
162 state of current_buffer's cache_long_line_scans variable. */
165 width_run_cache_on_off ()
167 if (NILP (current_buffer
->cache_long_line_scans
)
168 /* And, for the moment, this feature doesn't work on multibyte
170 || !NILP (current_buffer
->enable_multibyte_characters
))
172 /* It should be off. */
173 if (current_buffer
->width_run_cache
)
175 free_region_cache (current_buffer
->width_run_cache
);
176 current_buffer
->width_run_cache
= 0;
177 current_buffer
->width_table
= Qnil
;
182 /* It should be on. */
183 if (current_buffer
->width_run_cache
== 0)
185 current_buffer
->width_run_cache
= new_region_cache ();
186 recompute_width_table (current_buffer
, buffer_display_table ());
192 /* Skip some invisible characters starting from POS.
193 This includes characters invisible because of text properties
194 and characters invisible because of overlays.
196 If position POS is followed by invisible characters,
197 skip some of them and return the position after them.
198 Otherwise return POS itself.
200 Set *NEXT_BOUNDARY_P to the next position at which
201 it will be necessary to call this function again.
203 Don't scan past TO, and don't set *NEXT_BOUNDARY_P
204 to a value greater than TO.
206 If WINDOW is non-nil, and this buffer is displayed in WINDOW,
207 take account of overlays that apply only in WINDOW.
209 We don't necessarily skip all the invisible characters after POS
210 because that could take a long time. We skip a reasonable number
211 which can be skipped quickly. If there might be more invisible
212 characters immediately following, then *NEXT_BOUNDARY_P
213 will equal the return value. */
216 skip_invisible (pos
, next_boundary_p
, to
, window
)
218 int *next_boundary_p
;
222 Lisp_Object prop
, position
, overlay_limit
, proplimit
;
223 Lisp_Object buffer
, tmp
;
226 XSETFASTINT (position
, pos
);
227 XSETBUFFER (buffer
, current_buffer
);
229 /* Give faster response for overlay lookup near POS. */
230 recenter_overlay_lists (current_buffer
, pos
);
232 /* We must not advance farther than the next overlay change.
233 The overlay change might change the invisible property;
234 or there might be overlay strings to be displayed there. */
235 overlay_limit
= Fnext_overlay_change (position
);
236 /* As for text properties, this gives a lower bound
237 for where the invisible text property could change. */
238 proplimit
= Fnext_property_change (position
, buffer
, Qt
);
239 if (XFASTINT (overlay_limit
) < XFASTINT (proplimit
))
240 proplimit
= overlay_limit
;
241 /* PROPLIMIT is now a lower bound for the next change
242 in invisible status. If that is plenty far away,
243 use that lower bound. */
244 if (XFASTINT (proplimit
) > pos
+ 100 || XFASTINT (proplimit
) >= to
)
245 *next_boundary_p
= XFASTINT (proplimit
);
246 /* Otherwise, scan for the next `invisible' property change. */
249 /* Don't scan terribly far. */
250 XSETFASTINT (proplimit
, min (pos
+ 100, to
));
251 /* No matter what. don't go past next overlay change. */
252 if (XFASTINT (overlay_limit
) < XFASTINT (proplimit
))
253 proplimit
= overlay_limit
;
254 tmp
= Fnext_single_property_change (position
, Qinvisible
,
256 end
= XFASTINT (tmp
);
258 /* Don't put the boundary in the middle of multibyte form if
259 there is no actual property change. */
261 && !NILP (current_buffer
->enable_multibyte_characters
)
263 while (pos
< end
&& !CHAR_HEAD_P (POS_ADDR (end
)))
266 *next_boundary_p
= end
;
268 /* if the `invisible' property is set, we can skip to
269 the next property change */
270 prop
= Fget_char_property (position
, Qinvisible
,
272 && EQ (XWINDOW (window
)->buffer
, buffer
))
274 inv_p
= TEXT_PROP_MEANS_INVISIBLE (prop
);
275 /* When counting columns (window == nil), don't skip over ellipsis text. */
276 if (NILP (window
) ? inv_p
== 1 : inv_p
)
277 return *next_boundary_p
;
281 /* If a composition starts at POS/POS_BYTE and it doesn't stride over
282 POINT, set *LEN / *LEN_BYTE to the character and byte lengths, *WIDTH
283 to the width, and return 1. Otherwise, return 0. */
286 check_composition (pos
, pos_byte
, point
, len
, len_byte
, width
)
287 int pos
, pos_byte
, point
;
288 int *len
, *len_byte
, *width
;
294 if (! find_composition (pos
, -1, &start
, &end
, &prop
, Qnil
)
295 || pos
!= start
|| point
< end
296 || !COMPOSITION_VALID_P (start
, end
, prop
))
298 if ((id
= get_composition_id (pos
, pos_byte
, end
- pos
, prop
, Qnil
)) < 0)
301 *len
= COMPOSITION_LENGTH (prop
);
302 *len_byte
= CHAR_TO_BYTE (end
) - pos_byte
;
303 *width
= composition_table
[id
]->width
;
307 /* Set variables WIDTH and BYTES for a multibyte sequence starting at P.
309 DP is a display table or NULL.
311 This macro is used in current_column_1, Fmove_to_column, and
314 #define MULTIBYTE_BYTES_WIDTH(p, dp) \
319 c = STRING_CHAR_AND_LENGTH (p, MAX_MULTIBYTE_LENGTH, bytes); \
320 if (BYTES_BY_CHAR_HEAD (*p) != bytes) \
324 if (dp != 0 && VECTORP (DISP_CHAR_VECTOR (dp, c))) \
325 width = XVECTOR (DISP_CHAR_VECTOR (dp, c))->size; \
327 width = WIDTH_BY_CHAR_HEAD (*p); \
329 wide_column = width; \
334 DEFUN ("current-column", Fcurrent_column
, Scurrent_column
, 0, 0, 0,
335 doc
: /* Return the horizontal position of point. Beginning of line is column 0.
336 This is calculated by adding together the widths of all the displayed
337 representations of the character between the start of the previous line
338 and point (eg. control characters will have a width of 2 or 4, tabs
339 will have a variable width).
340 Ignores finite width of frame, which means that this function may return
341 values greater than (frame-width).
342 Whether the line is visible (if `selective-display' is t) has no effect;
343 however, ^M is treated as end of line when `selective-display' is t.
344 Text that has an invisible property is considered as having width 0, unless
345 `buffer-invisibility-spec' specifies that it is replaced by an ellipsis. */)
349 XSETFASTINT (temp
, (int) current_column ()); /* iftc */
353 /* Cancel any recorded value of the horizontal position. */
356 invalidate_current_column ()
358 last_known_column_point
= 0;
365 register unsigned char *ptr
, *stop
;
366 register int tab_seen
;
369 register int tab_width
= XINT (current_buffer
->tab_width
);
370 int ctl_arrow
= !NILP (current_buffer
->ctl_arrow
);
371 register struct Lisp_Char_Table
*dp
= buffer_display_table ();
373 if (PT
== last_known_column_point
374 && MODIFF
== last_known_column_modified
)
375 return last_known_column
;
377 /* If the buffer has overlays, text properties,
378 or multibyte characters, use a more general algorithm. */
379 if (BUF_INTERVALS (current_buffer
)
380 || current_buffer
->overlays_before
381 || current_buffer
->overlays_after
383 return current_column_1 ();
385 /* Scan backwards from point to the previous newline,
386 counting width. Tab characters are the only complicated case. */
388 /* Make a pointer for decrementing through the chars before point. */
389 ptr
= BYTE_POS_ADDR (PT_BYTE
- 1) + 1;
390 /* Make a pointer to where consecutive chars leave off,
391 going backwards from point. */
394 else if (PT
<= GPT
|| BEGV
> GPT
)
399 if (tab_width
<= 0 || tab_width
> 1000)
402 col
= 0, tab_seen
= 0, post_tab
= 0;
411 /* We stopped either for the beginning of the buffer
413 if (ptr
== BEGV_ADDR
)
416 /* It was the gap. Jump back over it. */
420 /* Check whether that brings us to beginning of buffer. */
427 if (dp
&& VECTORP (DISP_CHAR_VECTOR (dp
, c
)))
429 charvec
= DISP_CHAR_VECTOR (dp
, c
);
438 for (i
= n
- 1; i
>= 0; --i
)
440 if (VECTORP (charvec
))
442 /* This should be handled the same as
443 next_element_from_display_vector does it. */
444 Lisp_Object entry
= AREF (charvec
, i
);
447 && GLYPH_CHAR_VALID_P (XFASTINT (entry
)))
448 c
= FAST_GLYPH_CHAR (XFASTINT (entry
));
453 if (c
>= 040 && c
< 0177)
457 && EQ (current_buffer
->selective_display
, Qt
)))
460 goto start_of_line_found
;
465 col
= ((col
+ tab_width
) / tab_width
) * tab_width
;
471 else if (VECTORP (charvec
))
472 /* With a display table entry, C is displayed as is, and
473 not displayed as \NNN or as ^N. If C is a single-byte
474 character, it takes one column. If C is multi-byte in
475 an unibyte buffer, it's translated to unibyte, so it
476 also takes one column. */
479 col
+= (ctl_arrow
&& c
< 0200) ? 2 : 4;
487 col
= ((col
+ tab_width
) / tab_width
) * tab_width
;
491 if (ptr
== BEGV_ADDR
)
492 current_column_bol_cache
= BEGV
;
494 current_column_bol_cache
= BYTE_TO_CHAR (PTR_BYTE_POS (ptr
));
496 last_known_column
= col
;
497 last_known_column_point
= PT
;
498 last_known_column_modified
= MODIFF
;
503 /* Return the column number of position POS
504 by scanning forward from the beginning of the line.
505 This function handles characters that are invisible
506 due to text properties or overlays. */
511 register int tab_width
= XINT (current_buffer
->tab_width
);
512 register int ctl_arrow
= !NILP (current_buffer
->ctl_arrow
);
513 register struct Lisp_Char_Table
*dp
= buffer_display_table ();
514 int multibyte
= !NILP (current_buffer
->enable_multibyte_characters
);
516 /* Start the scan at the beginning of this line with column number 0. */
517 register int col
= 0;
520 int opoint
= PT
, opoint_byte
= PT_BYTE
;
522 scan_newline (PT
, PT_BYTE
, BEGV
, BEGV_BYTE
, -1, 1);
523 current_column_bol_cache
= PT
;
524 scan
= PT
, scan_byte
= PT_BYTE
;
525 SET_PT_BOTH (opoint
, opoint_byte
);
526 next_boundary
= scan
;
528 if (tab_width
<= 0 || tab_width
> 1000) tab_width
= 8;
530 /* Scan forward to the target position. */
531 while (scan
< opoint
)
535 /* Occasionally we may need to skip invisible text. */
536 while (scan
== next_boundary
)
539 /* This updates NEXT_BOUNDARY to the next place
540 where we might need to skip more invisible text. */
541 scan
= skip_invisible (scan
, &next_boundary
, opoint
, Qnil
);
544 if (scan
!= old_scan
)
545 scan_byte
= CHAR_TO_BYTE (scan
);
548 /* Check composition sequence. */
550 int len
, len_byte
, width
;
552 if (check_composition (scan
, scan_byte
, opoint
,
553 &len
, &len_byte
, &width
))
556 scan_byte
+= len_byte
;
563 c
= FETCH_BYTE (scan_byte
);
566 && ! (multibyte
&& BASE_LEADING_CODE_P (c
))
567 && VECTORP (DISP_CHAR_VECTOR (dp
, c
)))
572 /* This character is displayed using a vector of glyphs.
573 Update the column based on those glyphs. */
575 charvec
= DISP_CHAR_VECTOR (dp
, c
);
578 for (i
= 0; i
< n
; i
++)
580 /* This should be handled the same as
581 next_element_from_display_vector does it. */
583 entry
= AREF (charvec
, i
);
586 && GLYPH_CHAR_VALID_P (XFASTINT (entry
)))
587 c
= FAST_GLYPH_CHAR (XFASTINT (entry
));
593 if (c
== '\r' && EQ (current_buffer
->selective_display
, Qt
))
598 col
= col
/ tab_width
* tab_width
;
606 /* The display table says nothing for this character.
607 Display it as itself. */
611 if (c
== '\r' && EQ (current_buffer
->selective_display
, Qt
))
616 col
= col
/ tab_width
* tab_width
;
618 else if (multibyte
&& BASE_LEADING_CODE_P (c
))
621 int bytes
, width
, wide_column
;
623 ptr
= BYTE_POS_ADDR (scan_byte
);
624 MULTIBYTE_BYTES_WIDTH (ptr
, dp
);
626 /* Subtract one to compensate for the increment
627 that is going to happen below. */
631 else if (ctl_arrow
&& (c
< 040 || c
== 0177))
633 else if (c
< 040 || c
>= 0177)
644 last_known_column
= col
;
645 last_known_column_point
= PT
;
646 last_known_column_modified
= MODIFF
;
652 #if 0 /* Not used. */
654 /* Return the width in columns of the part of STRING from BEG to END.
655 If BEG is nil, that stands for the beginning of STRING.
656 If END is nil, that stands for the end of STRING. */
659 string_display_width (string
, beg
, end
)
660 Lisp_Object string
, beg
, end
;
663 register unsigned char *ptr
, *stop
;
664 register int tab_seen
;
667 register int tab_width
= XINT (current_buffer
->tab_width
);
668 int ctl_arrow
= !NILP (current_buffer
->ctl_arrow
);
669 register struct Lisp_Char_Table
*dp
= buffer_display_table ();
688 /* Make a pointer for decrementing through the chars before point. */
689 ptr
= SDATA (string
) + e
;
690 /* Make a pointer to where consecutive chars leave off,
691 going backwards from point. */
692 stop
= SDATA (string
) + b
;
694 if (tab_width
<= 0 || tab_width
> 1000) tab_width
= 8;
696 col
= 0, tab_seen
= 0, post_tab
= 0;
704 if (dp
!= 0 && VECTORP (DISP_CHAR_VECTOR (dp
, c
)))
705 col
+= XVECTOR (DISP_CHAR_VECTOR (dp
, c
))->size
;
706 else if (c
>= 040 && c
< 0177)
713 col
= ((col
+ tab_width
) / tab_width
) * tab_width
;
720 col
+= (ctl_arrow
&& c
< 0200) ? 2 : 4;
725 col
= ((col
+ tab_width
) / tab_width
) * tab_width
;
735 DEFUN ("indent-to", Findent_to
, Sindent_to
, 1, 2, "NIndent to column: ",
736 doc
: /* Indent from point with tabs and spaces until COLUMN is reached.
737 Optional second argument MINIMUM says always do at least MINIMUM spaces
738 even if that goes past COLUMN; by default, MINIMUM is zero.
740 The return value is COLUMN. */)
742 Lisp_Object column
, minimum
;
745 register int fromcol
;
746 register int tab_width
= XINT (current_buffer
->tab_width
);
748 CHECK_NUMBER (column
);
750 XSETFASTINT (minimum
, 0);
751 CHECK_NUMBER (minimum
);
753 fromcol
= current_column ();
754 mincol
= fromcol
+ XINT (minimum
);
755 if (mincol
< XINT (column
)) mincol
= XINT (column
);
757 if (fromcol
== mincol
)
758 return make_number (mincol
);
760 if (tab_width
<= 0 || tab_width
> 1000) tab_width
= 8;
762 if (indent_tabs_mode
)
765 XSETFASTINT (n
, mincol
/ tab_width
- fromcol
/ tab_width
);
766 if (XFASTINT (n
) != 0)
768 Finsert_char (make_number ('\t'), n
, Qt
);
770 fromcol
= (mincol
/ tab_width
) * tab_width
;
774 XSETFASTINT (column
, mincol
- fromcol
);
775 Finsert_char (make_number (' '), column
, Qt
);
777 last_known_column
= mincol
;
778 last_known_column_point
= PT
;
779 last_known_column_modified
= MODIFF
;
781 XSETINT (column
, mincol
);
786 static double position_indentation
P_ ((int));
788 DEFUN ("current-indentation", Fcurrent_indentation
, Scurrent_indentation
,
790 doc
: /* Return the indentation of the current line.
791 This is the horizontal position of the character
792 following any initial whitespace. */)
796 int opoint
= PT
, opoint_byte
= PT_BYTE
;
798 scan_newline (PT
, PT_BYTE
, BEGV
, BEGV_BYTE
, -1, 1);
800 XSETFASTINT (val
, (int) position_indentation (PT_BYTE
)); /* iftc */
801 SET_PT_BOTH (opoint
, opoint_byte
);
806 position_indentation (pos_byte
)
807 register int pos_byte
;
809 register int column
= 0;
810 register int tab_width
= XINT (current_buffer
->tab_width
);
811 register unsigned char *p
;
812 register unsigned char *stop
;
813 unsigned char *start
;
814 int next_boundary_byte
= pos_byte
;
815 int ceiling
= next_boundary_byte
;
817 if (tab_width
<= 0 || tab_width
> 1000) tab_width
= 8;
819 p
= BYTE_POS_ADDR (pos_byte
);
820 /* STOP records the value of P at which we will need
821 to think about the gap, or about invisible text,
822 or about the end of the buffer. */
824 /* START records the starting value of P. */
832 /* If we have updated P, set POS_BYTE to match.
833 The first time we enter the loop, POS_BYTE is already right. */
835 pos_byte
= PTR_BYTE_POS (p
);
836 /* Consider the various reasons STOP might have been set here. */
837 if (pos_byte
== ZV_BYTE
)
839 if (pos_byte
== next_boundary_byte
)
842 int pos
= BYTE_TO_CHAR (pos_byte
);
843 pos
= skip_invisible (pos
, &next_boundary
, ZV
, Qnil
);
844 pos_byte
= CHAR_TO_BYTE (pos
);
845 next_boundary_byte
= CHAR_TO_BYTE (next_boundary
);
847 if (pos_byte
>= ceiling
)
848 ceiling
= BUFFER_CEILING_OF (pos_byte
) + 1;
849 /* Compute the next place we need to stop and think,
850 and set STOP accordingly. */
851 stop_pos_byte
= min (ceiling
, next_boundary_byte
);
852 /* The -1 and +1 arrange to point at the first byte of gap
853 (if STOP_POS_BYTE is the position of the gap)
854 rather than at the data after the gap. */
856 stop
= BYTE_POS_ADDR (stop_pos_byte
- 1) + 1;
857 p
= BYTE_POS_ADDR (pos_byte
);
862 if (! NILP (current_buffer
->enable_multibyte_characters
))
868 column
+= tab_width
- column
% tab_width
;
871 if (ASCII_BYTE_P (p
[-1])
872 || NILP (current_buffer
->enable_multibyte_characters
))
876 pos_byte
= PTR_BYTE_POS (p
- 1);
877 c
= FETCH_MULTIBYTE_CHAR (pos_byte
);
878 if (CHAR_HAS_CATEGORY (c
, ' '))
882 p
= BYTE_POS_ADDR (pos_byte
);
891 /* Test whether the line beginning at POS is indented beyond COLUMN.
892 Blank lines are treated as if they had the same indentation as the
896 indented_beyond_p (pos
, pos_byte
, column
)
901 int opoint
= PT
, opoint_byte
= PT_BYTE
;
903 SET_PT_BOTH (pos
, pos_byte
);
904 while (PT
> BEGV
&& FETCH_BYTE (PT_BYTE
) == '\n')
905 scan_newline (PT
- 1, PT_BYTE
- 1, BEGV
, BEGV_BYTE
, -1, 0);
907 val
= position_indentation (PT_BYTE
);
908 SET_PT_BOTH (opoint
, opoint_byte
);
909 return val
>= column
; /* hmm, float comparison */
912 DEFUN ("move-to-column", Fmove_to_column
, Smove_to_column
, 1, 2, "p",
913 doc
: /* Move point to column COLUMN in the current line.
914 Interactively, COLUMN is the value of prefix numeric argument.
915 The column of a character is calculated by adding together the widths
916 as displayed of the previous characters in the line.
917 This function ignores line-continuation;
918 there is no upper limit on the column number a character can have
919 and horizontal scrolling has no effect.
921 If specified column is within a character, point goes after that character.
922 If it's past end of line, point goes to end of line.
924 Optional second argument FORCE non-nil means if COLUMN is in the
925 middle of a tab character, change it to spaces.
926 In addition, if FORCE is t, and the line is too short to reach
927 COLUMN, add spaces/tabs to get there.
929 The return value is the current column. */)
931 Lisp_Object column
, force
;
934 register int col
= current_column ();
937 register int tab_width
= XINT (current_buffer
->tab_width
);
938 register int ctl_arrow
= !NILP (current_buffer
->ctl_arrow
);
939 register struct Lisp_Char_Table
*dp
= buffer_display_table ();
940 register int multibyte
= !NILP (current_buffer
->enable_multibyte_characters
);
945 int next_boundary
, pos_byte
;
947 if (tab_width
<= 0 || tab_width
> 1000) tab_width
= 8;
948 CHECK_NATNUM (column
);
949 goal
= XINT (column
);
956 /* If we're starting past the desired column,
957 back up to beginning of line and scan from there. */
961 pos
= current_column_bol_cache
;
962 pos_byte
= CHAR_TO_BYTE (pos
);
968 while (pos
== next_boundary
)
971 pos
= skip_invisible (pos
, &next_boundary
, end
, Qnil
);
973 pos_byte
= CHAR_TO_BYTE (pos
);
978 /* Test reaching the goal column. We do this after skipping
979 invisible characters, so that we put point before the
980 character on which the cursor will appear. */
984 /* Check composition sequence. */
986 int len
, len_byte
, width
;
988 if (check_composition (pos
, pos_byte
, Z
, &len
, &len_byte
, &width
))
991 pos_byte
+= len_byte
;
997 c
= FETCH_BYTE (pos_byte
);
999 /* See if there is a display table and it relates
1000 to this character. */
1003 && ! (multibyte
&& BASE_LEADING_CODE_P (c
))
1004 && VECTORP (DISP_CHAR_VECTOR (dp
, c
)))
1006 Lisp_Object charvec
;
1009 /* This character is displayed using a vector of glyphs.
1010 Update the position based on those glyphs. */
1012 charvec
= DISP_CHAR_VECTOR (dp
, c
);
1013 n
= ASIZE (charvec
);
1015 for (i
= 0; i
< n
; i
++)
1017 /* This should be handled the same as
1018 next_element_from_display_vector does it. */
1021 entry
= AREF (charvec
, i
);
1023 if (INTEGERP (entry
)
1024 && GLYPH_CHAR_VALID_P (XFASTINT (entry
)))
1025 c
= FAST_GLYPH_CHAR (XFASTINT (entry
));
1031 if (c
== '\r' && EQ (current_buffer
->selective_display
, Qt
))
1037 col
= col
/ tab_width
* tab_width
;
1045 /* The display table doesn't affect this character;
1046 it displays as itself. */
1050 if (c
== '\r' && EQ (current_buffer
->selective_display
, Qt
))
1056 col
= col
/ tab_width
* tab_width
;
1058 else if (ctl_arrow
&& (c
< 040 || c
== 0177))
1060 else if (c
< 040 || c
== 0177)
1064 else if (multibyte
&& BASE_LEADING_CODE_P (c
))
1066 /* Start of multi-byte form. */
1068 int bytes
, width
, wide_column
;
1070 ptr
= BYTE_POS_ADDR (pos_byte
);
1071 MULTIBYTE_BYTES_WIDTH (ptr
, dp
);
1072 pos_byte
+= bytes
- 1;
1084 SET_PT_BOTH (pos
, pos_byte
);
1086 /* If a tab char made us overshoot, change it to spaces
1087 and scan through it again. */
1088 if (!NILP (force
) && col
> goal
&& c
== '\t' && prev_col
< goal
)
1090 int goal_pt
, goal_pt_byte
;
1092 /* Insert spaces in front of the tab to reach GOAL. Do this
1093 first so that a marker at the end of the tab gets
1095 SET_PT_BOTH (PT
- 1, PT_BYTE
- 1);
1096 Finsert_char (make_number (' '), make_number (goal
- prev_col
), Qt
);
1098 /* Now delete the tab, and indent to COL. */
1099 del_range (PT
, PT
+ 1);
1101 goal_pt_byte
= PT_BYTE
;
1102 Findent_to (make_number (col
), Qnil
);
1103 SET_PT_BOTH (goal_pt
, goal_pt_byte
);
1105 /* Set the last_known... vars consistently. */
1109 /* If line ends prematurely, add space to the end. */
1110 if (col
< goal
&& EQ (force
, Qt
))
1111 Findent_to (make_number (col
= goal
), Qnil
);
1113 last_known_column
= col
;
1114 last_known_column_point
= PT
;
1115 last_known_column_modified
= MODIFF
;
1117 XSETFASTINT (val
, col
);
1121 /* compute_motion: compute buffer posn given screen posn and vice versa */
1123 struct position val_compute_motion
;
1125 /* Scan the current buffer forward from offset FROM, pretending that
1126 this is at line FROMVPOS, column FROMHPOS, until reaching buffer
1127 offset TO or line TOVPOS, column TOHPOS (whichever comes first),
1128 and return the ending buffer position and screen location. If we
1129 can't hit the requested column exactly (because of a tab or other
1130 multi-column character), overshoot.
1132 DID_MOTION is 1 if FROMHPOS has already accounted for overlay strings
1133 at FROM. This is the case if FROMVPOS and FROMVPOS came from an
1134 earlier call to compute_motion. The other common case is that FROMHPOS
1135 is zero and FROM is a position that "belongs" at column zero, but might
1136 be shifted by overlay strings; in this case DID_MOTION should be 0.
1138 WIDTH is the number of columns available to display text;
1139 compute_motion uses this to handle continuation lines and such.
1140 If WIDTH is -1, use width of window's text area adjusted for
1141 continuation glyph when needed.
1143 HSCROLL is the number of columns not being displayed at the left
1144 margin; this is usually taken from a window's hscroll member.
1145 TAB_OFFSET is the number of columns of the first tab that aren't
1146 being displayed, perhaps because of a continuation line or
1149 compute_motion returns a pointer to a struct position. The bufpos
1150 member gives the buffer position at the end of the scan, and hpos
1151 and vpos give its cartesian location. prevhpos is the column at
1152 which the character before bufpos started, and contin is non-zero
1153 if we reached the current line by continuing the previous.
1155 Note that FROMHPOS and TOHPOS should be expressed in real screen
1156 columns, taking HSCROLL and the truncation glyph at the left margin
1157 into account. That is, beginning-of-line moves you to the hpos
1158 -HSCROLL + (HSCROLL > 0).
1160 For example, to find the buffer position of column COL of line LINE
1161 of a certain window, pass the window's starting location as FROM
1162 and the window's upper-left coordinates as FROMVPOS and FROMHPOS.
1163 Pass the buffer's ZV as TO, to limit the scan to the end of the
1164 visible section of the buffer, and pass LINE and COL as TOVPOS and
1167 When displaying in window w, a typical formula for WIDTH is:
1170 - (has_vertical_scroll_bars
1171 ? WINDOW_CONFIG_SCROLL_BAR_COLS (window)
1172 : (window_width + window_left != frame_cols))
1175 window_width is XFASTINT (w->total_cols),
1176 window_left is XFASTINT (w->left_col),
1177 has_vertical_scroll_bars is
1178 WINDOW_HAS_VERTICAL_SCROLL_BAR (window)
1179 and frame_cols = FRAME_COLS (XFRAME (window->frame))
1181 Or you can let window_box_text_cols do this all for you, and write:
1182 window_box_text_cols (w) - 1
1184 The `-1' accounts for the continuation-line backslashes; the rest
1185 accounts for window borders if the window is split horizontally, and
1186 the scroll bars if they are turned on. */
1189 compute_motion (from
, fromvpos
, fromhpos
, did_motion
, to
, tovpos
, tohpos
, width
, hscroll
, tab_offset
, win
)
1190 int from
, fromvpos
, fromhpos
, to
, tovpos
, tohpos
;
1193 int hscroll
, tab_offset
;
1196 register int hpos
= fromhpos
;
1197 register int vpos
= fromvpos
;
1202 register int tab_width
= XFASTINT (current_buffer
->tab_width
);
1203 register int ctl_arrow
= !NILP (current_buffer
->ctl_arrow
);
1204 register struct Lisp_Char_Table
*dp
= window_display_table (win
);
1206 = (INTEGERP (current_buffer
->selective_display
)
1207 ? XINT (current_buffer
->selective_display
)
1208 : !NILP (current_buffer
->selective_display
) ? -1 : 0);
1210 = (selective
&& dp
&& VECTORP (DISP_INVIS_VECTOR (dp
))
1211 ? XVECTOR (DISP_INVIS_VECTOR (dp
))->size
: 0);
1212 /* The next location where the `invisible' property changes, or an
1213 overlay starts or ends. */
1214 int next_boundary
= from
;
1216 /* For computing runs of characters with similar widths.
1217 Invariant: width_run_width is zero, or all the characters
1218 from width_run_start to width_run_end have a fixed width of
1220 int width_run_start
= from
;
1221 int width_run_end
= from
;
1222 int width_run_width
= 0;
1223 Lisp_Object
*width_table
;
1226 /* The next buffer pos where we should consult the width run cache. */
1227 int next_width_run
= from
;
1230 int multibyte
= !NILP (current_buffer
->enable_multibyte_characters
);
1231 /* If previous char scanned was a wide character,
1232 this is the column where it ended. Otherwise, this is 0. */
1233 int wide_column_end_hpos
= 0;
1234 int prev_pos
; /* Previous buffer position. */
1235 int prev_pos_byte
; /* Previous buffer position. */
1238 int contin_hpos
; /* HPOS of last column of continued line. */
1239 int prev_tab_offset
; /* Previous tab offset. */
1240 int continuation_glyph_width
;
1242 XSETBUFFER (buffer
, current_buffer
);
1243 XSETWINDOW (window
, win
);
1245 width_run_cache_on_off ();
1246 if (dp
== buffer_display_table ())
1247 width_table
= (VECTORP (current_buffer
->width_table
)
1248 ? XVECTOR (current_buffer
->width_table
)->contents
1251 /* If the window has its own display table, we can't use the width
1252 run cache, because that's based on the buffer's display table. */
1255 if (tab_width
<= 0 || tab_width
> 1000)
1258 /* Negative width means use all available text columns. */
1261 width
= window_box_text_cols (win
);
1262 /* We must make room for continuation marks if we don't have fringes. */
1263 #ifdef HAVE_WINDOW_SYSTEM
1264 if (!FRAME_WINDOW_P (XFRAME (win
->frame
)))
1269 continuation_glyph_width
= 1;
1270 #ifdef HAVE_WINDOW_SYSTEM
1271 if (FRAME_WINDOW_P (XFRAME (win
->frame
)))
1272 continuation_glyph_width
= 0; /* In the fringe. */
1278 pos
= prev_pos
= from
;
1279 pos_byte
= prev_pos_byte
= CHAR_TO_BYTE (from
);
1281 prev_tab_offset
= tab_offset
;
1284 while (pos
== next_boundary
)
1289 /* Don't skip invisible if we are already at the margin. */
1290 if (vpos
> tovpos
|| (vpos
== tovpos
&& hpos
>= tohpos
))
1292 if (contin_hpos
&& prev_hpos
== 0
1294 && (contin_hpos
== width
|| wide_column_end_hpos
> width
))
1295 { /* Line breaks because we can't put the character at the
1296 previous line any more. It is not the multi-column
1297 character continued in middle. Go back to previous
1298 buffer position, screen position, and set tab offset
1299 to previous value. It's the beginning of the
1302 pos_byte
= prev_pos_byte
;
1305 tab_offset
= prev_tab_offset
;
1310 /* If the caller says that the screen position came from an earlier
1311 call to compute_motion, then we've already accounted for the
1312 overlay strings at point. This is only true the first time
1313 through, so clear the flag after testing it. */
1315 /* We need to skip past the overlay strings. Currently those
1316 strings must not contain TAB;
1317 if we want to relax that restriction, something will have
1318 to be changed here. */
1320 unsigned char *ovstr
;
1321 int ovlen
= overlay_strings (pos
, win
, &ovstr
);
1322 hpos
+= ((multibyte
&& ovlen
> 0)
1323 ? strwidth (ovstr
, ovlen
) : ovlen
);
1330 /* Advance POS past invisible characters
1331 (but not necessarily all that there are here),
1332 and store in next_boundary the next position where
1333 we need to call skip_invisible. */
1334 newpos
= skip_invisible (pos
, &next_boundary
, to
, window
);
1338 pos
= min (to
, newpos
);
1339 pos_byte
= CHAR_TO_BYTE (pos
);
1343 if (newpos
!= pos_here
)
1346 pos_byte
= CHAR_TO_BYTE (pos
);
1350 /* Handle right margin. */
1351 /* Note on a wide-column character.
1353 Characters are classified into the following three categories
1354 according to the width (columns occupied on screen).
1356 (1) single-column character: ex. `a'
1357 (2) multi-column character: ex. `^A', TAB, `\033'
1358 (3) wide-column character: ex. Japanese character, Chinese character
1359 (In the following example, `W_' stands for them.)
1361 Multi-column characters can be divided around the right margin,
1362 but wide-column characters cannot.
1366 (*) The cursor is placed on the next character after the point.
1370 j ^---- next after the point
1371 ^--- next char. after the point.
1373 In case of sigle-column character
1377 033 ^---- next after the point, next char. after the point.
1379 In case of multi-column character
1383 W_ ^---- next after the point
1384 ^---- next char. after the point.
1386 In case of wide-column character
1388 The problem here is continuation at a wide-column character.
1389 In this case, the line may shorter less than WIDTH.
1390 And we find the continuation AFTER it occurs.
1397 || (truncate_partial_width_windows
1398 && ((width
+ continuation_glyph_width
)
1399 < FRAME_COLS (XFRAME (WINDOW_FRAME (win
)))))
1400 || !NILP (current_buffer
->truncate_lines
))
1402 /* Truncating: skip to newline, unless we are already past
1403 TO (we need to go back below). */
1406 pos
= find_before_next_newline (pos
, to
, 1);
1407 pos_byte
= CHAR_TO_BYTE (pos
);
1409 /* If we just skipped next_boundary,
1410 loop around in the main while
1412 if (pos
>= next_boundary
)
1413 next_boundary
= pos
+ 1;
1416 prev_tab_offset
= tab_offset
;
1422 /* Remember the previous value. */
1423 prev_tab_offset
= tab_offset
;
1425 if (wide_column_end_hpos
> width
)
1428 tab_offset
+= prev_hpos
;
1432 tab_offset
+= width
;
1436 contin_hpos
= prev_hpos
;
1442 /* Stop if past the target buffer position or screen position. */
1445 /* Go back to the previous position. */
1447 pos_byte
= prev_pos_byte
;
1450 tab_offset
= prev_tab_offset
;
1452 /* NOTE on contin_hpos, hpos, and prev_hpos.
1456 W_ ^---- contin_hpos
1462 if (contin_hpos
&& prev_hpos
== 0
1463 && contin_hpos
< width
&& !wide_column_end_hpos
)
1465 /* Line breaking occurs in the middle of multi-column
1466 character. Go back to previous line. */
1473 if (vpos
> tovpos
|| (vpos
== tovpos
&& hpos
>= tohpos
))
1475 if (contin_hpos
&& prev_hpos
== 0
1477 && (contin_hpos
== width
|| wide_column_end_hpos
> width
))
1478 { /* Line breaks because we can't put the character at the
1479 previous line any more. It is not the multi-column
1480 character continued in middle. Go back to previous
1481 buffer position, screen position, and set tab offset
1482 to previous value. It's the beginning of the
1485 pos_byte
= prev_pos_byte
;
1488 tab_offset
= prev_tab_offset
;
1492 if (pos
== ZV
) /* We cannot go beyond ZV. Stop here. */
1498 prev_pos_byte
= pos_byte
;
1499 wide_column_end_hpos
= 0;
1501 /* Consult the width run cache to see if we can avoid inspecting
1502 the text character-by-character. */
1503 if (current_buffer
->width_run_cache
&& pos
>= next_width_run
)
1507 = region_cache_forward (current_buffer
,
1508 current_buffer
->width_run_cache
,
1511 /* A width of zero means the character's width varies (like
1512 a tab), is meaningless (like a newline), or we just don't
1513 want to skip over it for some other reason. */
1514 if (common_width
!= 0)
1518 /* Don't go past the final buffer posn the user
1523 run_end_hpos
= hpos
+ (run_end
- pos
) * common_width
;
1525 /* Don't go past the final horizontal position the user
1527 if (vpos
== tovpos
&& run_end_hpos
> tohpos
)
1529 run_end
= pos
+ (tohpos
- hpos
) / common_width
;
1530 run_end_hpos
= hpos
+ (run_end
- pos
) * common_width
;
1533 /* Don't go past the margin. */
1534 if (run_end_hpos
>= width
)
1536 run_end
= pos
+ (width
- hpos
) / common_width
;
1537 run_end_hpos
= hpos
+ (run_end
- pos
) * common_width
;
1540 hpos
= run_end_hpos
;
1542 prev_hpos
= hpos
- common_width
;
1546 pos_byte
= CHAR_TO_BYTE (pos
);
1550 next_width_run
= run_end
+ 1;
1553 /* We have to scan the text character-by-character. */
1557 Lisp_Object charvec
;
1559 c
= FETCH_BYTE (pos_byte
);
1561 /* Check composition sequence. */
1563 int len
, len_byte
, width
;
1565 if (check_composition (pos
, pos_byte
, to
, &len
, &len_byte
, &width
))
1568 pos_byte
+= len_byte
;
1576 /* Perhaps add some info to the width_run_cache. */
1577 if (current_buffer
->width_run_cache
)
1579 /* Is this character part of the current run? If so, extend
1581 if (pos
- 1 == width_run_end
1582 && XFASTINT (width_table
[c
]) == width_run_width
)
1583 width_run_end
= pos
;
1585 /* The previous run is over, since this is a character at a
1586 different position, or a different width. */
1589 /* Have we accumulated a run to put in the cache?
1590 (Currently, we only cache runs of width == 1). */
1591 if (width_run_start
< width_run_end
1592 && width_run_width
== 1)
1593 know_region_cache (current_buffer
,
1594 current_buffer
->width_run_cache
,
1595 width_run_start
, width_run_end
);
1597 /* Start recording a new width run. */
1598 width_run_width
= XFASTINT (width_table
[c
]);
1599 width_run_start
= pos
- 1;
1600 width_run_end
= pos
;
1605 && ! (multibyte
&& BASE_LEADING_CODE_P (c
))
1606 && VECTORP (DISP_CHAR_VECTOR (dp
, c
)))
1608 charvec
= DISP_CHAR_VECTOR (dp
, c
);
1609 n
= ASIZE (charvec
);
1617 for (i
= n
- 1; i
>= 0; --i
)
1619 if (VECTORP (charvec
))
1621 /* This should be handled the same as
1622 next_element_from_display_vector does it. */
1623 Lisp_Object entry
= AREF (charvec
, i
);
1625 if (INTEGERP (entry
)
1626 && GLYPH_CHAR_VALID_P (XFASTINT (entry
)))
1627 c
= FAST_GLYPH_CHAR (XFASTINT (entry
));
1632 if (c
>= 040 && c
< 0177)
1636 int tem
= ((hpos
+ tab_offset
+ hscroll
- (hscroll
> 0))
1640 hpos
+= tab_width
- tem
;
1645 && indented_beyond_p (pos
, pos_byte
,
1646 (double) selective
)) /* iftc */
1648 /* If (pos == to), we don't have to take care of
1649 selective display. */
1652 /* Skip any number of invisible lines all at once */
1655 pos
= find_before_next_newline (pos
, to
, 1);
1658 pos_byte
= CHAR_TO_BYTE (pos
);
1661 && indented_beyond_p (pos
, pos_byte
,
1662 (double) selective
)); /* iftc */
1663 /* Allow for the " ..." that is displayed for them. */
1666 hpos
+= selective_rlen
;
1670 DEC_BOTH (pos
, pos_byte
);
1671 /* We have skipped the invis text, but not the
1677 /* A visible line. */
1681 /* Count the truncation glyph on column 0 */
1683 hpos
+= continuation_glyph_width
;
1688 else if (c
== CR
&& selective
< 0)
1690 /* In selective display mode,
1691 everything from a ^M to the end of the line is invisible.
1692 Stop *before* the real newline. */
1695 pos
= find_before_next_newline (pos
, to
, 1);
1696 pos_byte
= CHAR_TO_BYTE (pos
);
1698 /* If we just skipped next_boundary,
1699 loop around in the main while
1701 if (pos
> next_boundary
)
1702 next_boundary
= pos
;
1703 /* Allow for the " ..." that is displayed for them. */
1706 hpos
+= selective_rlen
;
1711 else if (multibyte
&& BASE_LEADING_CODE_P (c
))
1713 /* Start of multi-byte form. */
1715 int bytes
, width
, wide_column
;
1717 pos_byte
--; /* rewind POS_BYTE */
1718 ptr
= BYTE_POS_ADDR (pos_byte
);
1719 MULTIBYTE_BYTES_WIDTH (ptr
, dp
);
1722 wide_column_end_hpos
= hpos
+ wide_column
;
1725 else if (VECTORP (charvec
))
1728 hpos
+= (ctl_arrow
&& c
< 0200) ? 2 : 4;
1735 /* Remember any final width run in the cache. */
1736 if (current_buffer
->width_run_cache
1737 && width_run_width
== 1
1738 && width_run_start
< width_run_end
)
1739 know_region_cache (current_buffer
, current_buffer
->width_run_cache
,
1740 width_run_start
, width_run_end
);
1742 val_compute_motion
.bufpos
= pos
;
1743 val_compute_motion
.bytepos
= pos_byte
;
1744 val_compute_motion
.hpos
= hpos
;
1745 val_compute_motion
.vpos
= vpos
;
1746 if (contin_hpos
&& prev_hpos
== 0)
1747 val_compute_motion
.prevhpos
= contin_hpos
;
1749 val_compute_motion
.prevhpos
= prev_hpos
;
1750 /* We alalways handle all of them here; none of them remain to do. */
1751 val_compute_motion
.ovstring_chars_done
= 0;
1753 /* Nonzero if have just continued a line */
1754 val_compute_motion
.contin
= (contin_hpos
&& prev_hpos
== 0);
1757 return &val_compute_motion
;
1761 DEFUN ("compute-motion", Fcompute_motion
, Scompute_motion
, 7, 7, 0,
1762 doc
: /* Scan through the current buffer, calculating screen position.
1763 Scan the current buffer forward from offset FROM,
1764 assuming it is at position FROMPOS--a cons of the form (HPOS . VPOS)--
1765 to position TO or position TOPOS--another cons of the form (HPOS . VPOS)--
1766 and return the ending buffer position and screen location.
1768 If TOPOS is nil, the actual width and height of the window's
1771 There are three additional arguments:
1773 WIDTH is the number of columns available to display text;
1774 this affects handling of continuation lines. A value of nil
1775 corresponds to the actual number of available text columns.
1777 OFFSETS is either nil or a cons cell (HSCROLL . TAB-OFFSET).
1778 HSCROLL is the number of columns not being displayed at the left
1779 margin; this is usually taken from a window's hscroll member.
1780 TAB-OFFSET is the number of columns of the first tab that aren't
1781 being displayed, perhaps because the line was continued within it.
1782 If OFFSETS is nil, HSCROLL and TAB-OFFSET are assumed to be zero.
1784 WINDOW is the window to operate on. It is used to choose the display table;
1785 if it is showing the current buffer, it is used also for
1786 deciding which overlay properties apply.
1787 Note that `compute-motion' always operates on the current buffer.
1789 The value is a list of five elements:
1790 (POS HPOS VPOS PREVHPOS CONTIN)
1791 POS is the buffer position where the scan stopped.
1792 VPOS is the vertical position where the scan stopped.
1793 HPOS is the horizontal position where the scan stopped.
1795 PREVHPOS is the horizontal position one character back from POS.
1796 CONTIN is t if a line was continued after (or within) the previous character.
1798 For example, to find the buffer position of column COL of line LINE
1799 of a certain window, pass the window's starting location as FROM
1800 and the window's upper-left coordinates as FROMPOS.
1801 Pass the buffer's (point-max) as TO, to limit the scan to the end of the
1802 visible section of the buffer, and pass LINE and COL as TOPOS. */)
1803 (from
, frompos
, to
, topos
, width
, offsets
, window
)
1804 Lisp_Object from
, frompos
, to
, topos
;
1805 Lisp_Object width
, offsets
, window
;
1808 Lisp_Object bufpos
, hpos
, vpos
, prevhpos
;
1809 struct position
*pos
;
1810 int hscroll
, tab_offset
;
1812 CHECK_NUMBER_COERCE_MARKER (from
);
1813 CHECK_CONS (frompos
);
1814 CHECK_NUMBER_CAR (frompos
);
1815 CHECK_NUMBER_CDR (frompos
);
1816 CHECK_NUMBER_COERCE_MARKER (to
);
1820 CHECK_NUMBER_CAR (topos
);
1821 CHECK_NUMBER_CDR (topos
);
1824 CHECK_NUMBER (width
);
1826 if (!NILP (offsets
))
1828 CHECK_CONS (offsets
);
1829 CHECK_NUMBER_CAR (offsets
);
1830 CHECK_NUMBER_CDR (offsets
);
1831 hscroll
= XINT (XCAR (offsets
));
1832 tab_offset
= XINT (XCDR (offsets
));
1835 hscroll
= tab_offset
= 0;
1838 window
= Fselected_window ();
1840 CHECK_LIVE_WINDOW (window
);
1841 w
= XWINDOW (window
);
1843 if (XINT (from
) < BEGV
|| XINT (from
) > ZV
)
1844 args_out_of_range_3 (from
, make_number (BEGV
), make_number (ZV
));
1845 if (XINT (to
) < BEGV
|| XINT (to
) > ZV
)
1846 args_out_of_range_3 (to
, make_number (BEGV
), make_number (ZV
));
1848 pos
= compute_motion (XINT (from
), XINT (XCDR (frompos
)),
1849 XINT (XCAR (frompos
)), 0,
1852 ? window_internal_height (w
)
1853 : XINT (XCDR (topos
))),
1855 ? (window_box_text_cols (w
)
1857 #ifdef HAVE_WINDOW_SYSTEM
1858 FRAME_WINDOW_P (XFRAME (w
->frame
)) ? 0 :
1861 : XINT (XCAR (topos
))),
1862 (NILP (width
) ? -1 : XINT (width
)),
1863 hscroll
, tab_offset
,
1866 XSETFASTINT (bufpos
, pos
->bufpos
);
1867 XSETINT (hpos
, pos
->hpos
);
1868 XSETINT (vpos
, pos
->vpos
);
1869 XSETINT (prevhpos
, pos
->prevhpos
);
1871 return Fcons (bufpos
,
1875 Fcons (pos
->contin
? Qt
: Qnil
, Qnil
)))));
1879 /* Fvertical_motion and vmotion */
1881 struct position val_vmotion
;
1884 vmotion (from
, vtarget
, w
)
1885 register int from
, vtarget
;
1888 int hscroll
= XINT (w
->hscroll
);
1889 struct position pos
;
1890 /* vpos is cumulative vertical position, changed as from is changed */
1891 register int vpos
= 0;
1895 int lmargin
= hscroll
> 0 ? 1 - hscroll
: 0;
1897 = (INTEGERP (current_buffer
->selective_display
)
1898 ? XINT (current_buffer
->selective_display
)
1899 : !NILP (current_buffer
->selective_display
) ? -1 : 0);
1903 /* This is the object we use for fetching character properties. */
1904 Lisp_Object text_prop_object
;
1906 XSETWINDOW (window
, w
);
1908 /* If the window contains this buffer, use it for getting text properties.
1909 Otherwise use the current buffer as arg for doing that. */
1910 if (EQ (w
->buffer
, Fcurrent_buffer ()))
1911 text_prop_object
= window
;
1913 text_prop_object
= Fcurrent_buffer ();
1915 if (vpos
>= vtarget
)
1917 /* To move upward, go a line at a time until
1918 we have gone at least far enough. */
1922 while ((vpos
> vtarget
|| first
) && from
> BEGV
)
1924 Lisp_Object propval
;
1926 prevline
= find_next_newline_no_quit (from
- 1, -1);
1927 while (prevline
> BEGV
1929 && indented_beyond_p (prevline
,
1930 CHAR_TO_BYTE (prevline
),
1931 (double) selective
)) /* iftc */
1932 /* Watch out for newlines with `invisible' property.
1933 When moving upward, check the newline before. */
1934 || (propval
= Fget_char_property (make_number (prevline
- 1),
1937 TEXT_PROP_MEANS_INVISIBLE (propval
))))
1938 prevline
= find_next_newline_no_quit (prevline
- 1, -1);
1939 pos
= *compute_motion (prevline
, 0,
1940 lmargin
+ (prevline
== BEG
? start_hpos
: 0),
1943 /* Don't care for VPOS... */
1944 1 << (BITS_PER_SHORT
- 1),
1946 1 << (BITS_PER_SHORT
- 1),
1948 /* This compensates for start_hpos
1949 so that a tab as first character
1950 still occupies 8 columns. */
1951 (prevline
== BEG
? -start_hpos
: 0),
1958 /* If we made exactly the desired vertical distance,
1959 or if we hit beginning of buffer,
1960 return point found */
1961 if (vpos
>= vtarget
)
1963 val_vmotion
.bufpos
= from
;
1964 val_vmotion
.bytepos
= CHAR_TO_BYTE (from
);
1965 val_vmotion
.vpos
= vpos
;
1966 val_vmotion
.hpos
= lmargin
;
1967 val_vmotion
.contin
= 0;
1968 val_vmotion
.prevhpos
= 0;
1969 val_vmotion
.ovstring_chars_done
= 0;
1970 val_vmotion
.tab_offset
= 0; /* For accumulating tab offset. */
1971 return &val_vmotion
;
1974 /* Otherwise find the correct spot by moving down */
1976 /* Moving downward is simple, but must calculate from beg of line
1977 to determine hpos of starting point */
1978 from_byte
= CHAR_TO_BYTE (from
);
1979 if (from
> BEGV
&& FETCH_BYTE (from_byte
- 1) != '\n')
1981 Lisp_Object propval
;
1983 prevline
= find_next_newline_no_quit (from
, -1);
1984 while (prevline
> BEGV
1986 && indented_beyond_p (prevline
,
1987 CHAR_TO_BYTE (prevline
),
1988 (double) selective
)) /* iftc */
1989 /* Watch out for newlines with `invisible' property.
1990 When moving downward, check the newline after. */
1991 || (propval
= Fget_char_property (make_number (prevline
),
1994 TEXT_PROP_MEANS_INVISIBLE (propval
))))
1995 prevline
= find_next_newline_no_quit (prevline
- 1, -1);
1996 pos
= *compute_motion (prevline
, 0,
1997 lmargin
+ (prevline
== BEG
2001 /* Don't care for VPOS... */
2002 1 << (BITS_PER_SHORT
- 1),
2004 1 << (BITS_PER_SHORT
- 1),
2006 (prevline
== BEG
? -start_hpos
: 0),
2012 pos
.hpos
= lmargin
+ (from
== BEG
? start_hpos
: 0);
2017 return compute_motion (from
, vpos
, pos
.hpos
, did_motion
,
2018 ZV
, vtarget
, - (1 << (BITS_PER_SHORT
- 1)),
2020 pos
.tab_offset
- (from
== BEG
? start_hpos
: 0),
2024 DEFUN ("vertical-motion", Fvertical_motion
, Svertical_motion
, 1, 2, 0,
2025 doc
: /* Move point to start of the screen line LINES lines down.
2026 If LINES is negative, this means moving up.
2028 This function is an ordinary cursor motion function
2029 which calculates the new position based on how text would be displayed.
2030 The new position may be the start of a line,
2031 or just the start of a continuation line.
2032 The function returns number of screen lines moved over;
2033 that usually equals LINES, but may be closer to zero
2034 if beginning or end of buffer was reached.
2036 The optional second argument WINDOW specifies the window to use for
2037 parameters such as width, horizontal scrolling, and so on.
2038 The default is to use the selected window's parameters.
2040 `vertical-motion' always uses the current buffer,
2041 regardless of which buffer is displayed in WINDOW.
2042 This is consistent with other cursor motion functions
2043 and makes it possible to use `vertical-motion' in any buffer,
2044 whether or not it is currently displayed in some window. */)
2046 Lisp_Object lines
, window
;
2051 Lisp_Object old_buffer
;
2052 struct gcpro gcpro1
;
2054 CHECK_NUMBER (lines
);
2055 if (! NILP (window
))
2056 CHECK_WINDOW (window
);
2058 window
= selected_window
;
2059 w
= XWINDOW (window
);
2062 GCPRO1 (old_buffer
);
2063 if (XBUFFER (w
->buffer
) != current_buffer
)
2065 /* Set the window's buffer temporarily to the current buffer. */
2066 old_buffer
= w
->buffer
;
2067 XSETBUFFER (w
->buffer
, current_buffer
);
2072 struct position pos
;
2073 pos
= *vmotion (PT
, XINT (lines
), w
);
2074 SET_PT_BOTH (pos
.bufpos
, pos
.bytepos
);
2080 int it_overshoot_expected
;
2082 SET_TEXT_POS (pt
, PT
, PT_BYTE
);
2083 start_display (&it
, w
, pt
);
2085 /* Scan from the start of the line containing PT. If we don't
2086 do this, we start moving with IT->current_x == 0, while PT is
2087 really at some x > 0. The effect is, in continuation lines, that
2088 we end up with the iterator placed at where it thinks X is 0,
2089 while the end position is really at some X > 0, the same X that
2091 it_start
= IT_CHARPOS (it
);
2093 /* We expect the call to move_it_to, further down, to overshoot
2094 if the starting point is on an image, stretch glyph,
2095 composition, or Lisp string. We won't need to backtrack in
2096 this situation, except for one corner case: when the Lisp
2097 string contains a newline. */
2098 if (it
.method
== GET_FROM_STRING
)
2100 const char *s
= SDATA (it
.string
);
2101 const char *e
= s
+ SBYTES (it
.string
);
2103 while (s
< e
&& *s
!= '\n')
2106 /* If there is no newline in the string, we need to check
2107 whether there is a newline immediately after the string
2108 in move_it_to below. This may happen if there is an
2109 overlay with an after-string just before the newline. */
2110 it_overshoot_expected
= (s
== e
) ? -1 : 0;
2113 it_overshoot_expected
= (it
.method
== GET_FROM_IMAGE
2114 || it
.method
== GET_FROM_STRETCH
2115 || it
.method
== GET_FROM_COMPOSITION
);
2117 reseat_at_previous_visible_line_start (&it
);
2118 it
.current_x
= it
.hpos
= 0;
2119 /* Temporarily disable selective display so we don't move too far */
2120 oselective
= it
.selective
;
2122 move_it_to (&it
, PT
, -1, -1, -1, MOVE_TO_POS
);
2123 it
.selective
= oselective
;
2125 /* Move back if we got too far. This may happen if
2126 truncate-lines is on and PT is beyond right margin.
2127 Don't go back if the overshoot is expected (see above). */
2128 if (IT_CHARPOS (it
) > it_start
&& XINT (lines
) > 0
2129 && (!it_overshoot_expected
2130 || (it_overshoot_expected
< 0
2131 && it
.method
== GET_FROM_BUFFER
2133 move_it_by_lines (&it
, -1, 0);
2136 /* Do this even if LINES is 0, so that we move back
2137 to the beginning of the current line as we ought. */
2138 if (XINT (lines
) >= 0 || IT_CHARPOS (it
) > 0)
2139 move_it_by_lines (&it
, XINT (lines
), 0);
2141 SET_PT_BOTH (IT_CHARPOS (it
), IT_BYTEPOS (it
));
2144 if (BUFFERP (old_buffer
))
2145 w
->buffer
= old_buffer
;
2147 RETURN_UNGCPRO (make_number (it
.vpos
));
2152 /* File's initialization. */
2157 DEFVAR_BOOL ("indent-tabs-mode", &indent_tabs_mode
,
2158 doc
: /* *Indentation can insert tabs if this is non-nil.
2159 Setting this variable automatically makes it local to the current buffer. */);
2160 indent_tabs_mode
= 1;
2162 defsubr (&Scurrent_indentation
);
2163 defsubr (&Sindent_to
);
2164 defsubr (&Scurrent_column
);
2165 defsubr (&Smove_to_column
);
2166 defsubr (&Svertical_motion
);
2167 defsubr (&Scompute_motion
);
2170 /* arch-tag: 9adfea44-71f7-4988-8ee3-96da15c502cc
2171 (do not change this comment) */