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. */
36 #include "intervals.h"
37 #include "region-cache.h"
39 /* Indentation can insert tabs if this is non-zero;
40 otherwise always uses spaces. */
46 /* These three values memorize the current column to avoid recalculation. */
48 /* Last value returned by current_column.
49 Some things in set last_known_column_point to -1
50 to mark the memorized value as invalid. */
52 double last_known_column
;
54 /* Value of point when current_column was called. */
56 int last_known_column_point
;
58 /* Value of MODIFF when current_column was called. */
60 int last_known_column_modified
;
62 static double current_column_1
P_ ((void));
63 static double position_indentation
P_ ((int));
65 /* Cache of beginning of line found by the last call of
68 int current_column_bol_cache
;
70 /* Get the display table to use for the current buffer. */
72 struct Lisp_Char_Table
*
73 buffer_display_table ()
77 thisbuf
= current_buffer
->display_table
;
78 if (DISP_TABLE_P (thisbuf
))
79 return XCHAR_TABLE (thisbuf
);
80 if (DISP_TABLE_P (Vstandard_display_table
))
81 return XCHAR_TABLE (Vstandard_display_table
);
85 /* Width run cache considerations. */
87 /* Return the width of character C under display table DP. */
90 character_width (c
, dp
)
92 struct Lisp_Char_Table
*dp
;
96 /* These width computations were determined by examining the cases
97 in display_text_line. */
99 /* Everything can be handled by the display table, if it's
100 present and the element is right. */
101 if (dp
&& (elt
= DISP_CHAR_VECTOR (dp
, c
), VECTORP (elt
)))
102 return XVECTOR (elt
)->size
;
104 /* Some characters are special. */
105 if (c
== '\n' || c
== '\t' || c
== '\015')
108 /* Printing characters have width 1. */
109 else if (c
>= 040 && c
< 0177)
112 /* Everybody else (control characters, metacharacters) has other
113 widths. We could return their actual widths here, but they
114 depend on things like ctl_arrow and crud like that, and they're
115 not very common at all. So we'll just claim we don't know their
121 /* Return true iff the display table DISPTAB specifies the same widths
122 for characters as WIDTHTAB. We use this to decide when to
123 invalidate the buffer's width_run_cache. */
126 disptab_matches_widthtab (disptab
, widthtab
)
127 struct Lisp_Char_Table
*disptab
;
128 struct Lisp_Vector
*widthtab
;
132 if (widthtab
->size
!= 256)
135 for (i
= 0; i
< 256; i
++)
136 if (character_width (i
, disptab
)
137 != XFASTINT (widthtab
->contents
[i
]))
143 /* Recompute BUF's width table, using the display table DISPTAB. */
146 recompute_width_table (buf
, disptab
)
148 struct Lisp_Char_Table
*disptab
;
151 struct Lisp_Vector
*widthtab
;
153 if (!VECTORP (buf
->width_table
))
154 buf
->width_table
= Fmake_vector (make_number (256), make_number (0));
155 widthtab
= XVECTOR (buf
->width_table
);
156 if (widthtab
->size
!= 256)
159 for (i
= 0; i
< 256; i
++)
160 XSETFASTINT (widthtab
->contents
[i
], character_width (i
, disptab
));
163 /* Allocate or free the width run cache, as requested by the current
164 state of current_buffer's cache_long_line_scans variable. */
167 width_run_cache_on_off ()
169 if (NILP (current_buffer
->cache_long_line_scans
)
170 /* And, for the moment, this feature doesn't work on multibyte
172 || !NILP (current_buffer
->enable_multibyte_characters
))
174 /* It should be off. */
175 if (current_buffer
->width_run_cache
)
177 free_region_cache (current_buffer
->width_run_cache
);
178 current_buffer
->width_run_cache
= 0;
179 current_buffer
->width_table
= Qnil
;
184 /* It should be on. */
185 if (current_buffer
->width_run_cache
== 0)
187 current_buffer
->width_run_cache
= new_region_cache ();
188 recompute_width_table (current_buffer
, buffer_display_table ());
194 /* Skip some invisible characters starting from POS.
195 This includes characters invisible because of text properties
196 and characters invisible because of overlays.
198 If position POS is followed by invisible characters,
199 skip some of them and return the position after them.
200 Otherwise return POS itself.
202 Set *NEXT_BOUNDARY_P to the next position at which
203 it will be necessary to call this function again.
205 Don't scan past TO, and don't set *NEXT_BOUNDARY_P
206 to a value greater than TO.
208 If WINDOW is non-nil, and this buffer is displayed in WINDOW,
209 take account of overlays that apply only in WINDOW.
211 We don't necessarily skip all the invisible characters after POS
212 because that could take a long time. We skip a reasonable number
213 which can be skipped quickly. If there might be more invisible
214 characters immediately following, then *NEXT_BOUNDARY_P
215 will equal the return value. */
218 skip_invisible (pos
, next_boundary_p
, to
, window
)
220 int *next_boundary_p
;
224 Lisp_Object prop
, position
, overlay_limit
, proplimit
;
225 Lisp_Object buffer
, tmp
;
228 XSETFASTINT (position
, pos
);
229 XSETBUFFER (buffer
, current_buffer
);
231 /* Give faster response for overlay lookup near POS. */
232 recenter_overlay_lists (current_buffer
, pos
);
234 /* We must not advance farther than the next overlay change.
235 The overlay change might change the invisible property;
236 or there might be overlay strings to be displayed there. */
237 overlay_limit
= Fnext_overlay_change (position
);
238 /* As for text properties, this gives a lower bound
239 for where the invisible text property could change. */
240 proplimit
= Fnext_property_change (position
, buffer
, Qt
);
241 if (XFASTINT (overlay_limit
) < XFASTINT (proplimit
))
242 proplimit
= overlay_limit
;
243 /* PROPLIMIT is now a lower bound for the next change
244 in invisible status. If that is plenty far away,
245 use that lower bound. */
246 if (XFASTINT (proplimit
) > pos
+ 100 || XFASTINT (proplimit
) >= to
)
247 *next_boundary_p
= XFASTINT (proplimit
);
248 /* Otherwise, scan for the next `invisible' property change. */
251 /* Don't scan terribly far. */
252 XSETFASTINT (proplimit
, min (pos
+ 100, to
));
253 /* No matter what. don't go past next overlay change. */
254 if (XFASTINT (overlay_limit
) < XFASTINT (proplimit
))
255 proplimit
= overlay_limit
;
256 tmp
= Fnext_single_property_change (position
, Qinvisible
,
258 end
= XFASTINT (tmp
);
260 /* Don't put the boundary in the middle of multibyte form if
261 there is no actual property change. */
263 && !NILP (current_buffer
->enable_multibyte_characters
)
265 while (pos
< end
&& !CHAR_HEAD_P (POS_ADDR (end
)))
268 *next_boundary_p
= end
;
270 /* if the `invisible' property is set, we can skip to
271 the next property change */
272 prop
= Fget_char_property (position
, Qinvisible
,
274 && EQ (XWINDOW (window
)->buffer
, buffer
))
276 inv_p
= TEXT_PROP_MEANS_INVISIBLE (prop
);
277 /* When counting columns (window == nil), don't skip over ellipsis text. */
278 if (NILP (window
) ? inv_p
== 1 : inv_p
)
279 return *next_boundary_p
;
283 /* If a composition starts at POS/POS_BYTE and it doesn't stride over
284 POINT, set *LEN / *LEN_BYTE to the character and byte lengths, *WIDTH
285 to the width, and return 1. Otherwise, return 0. */
288 check_composition (pos
, pos_byte
, point
, len
, len_byte
, width
)
289 int pos
, pos_byte
, point
;
290 int *len
, *len_byte
, *width
;
296 if (! find_composition (pos
, -1, &start
, &end
, &prop
, Qnil
)
297 || pos
!= start
|| point
< end
298 || !COMPOSITION_VALID_P (start
, end
, prop
))
300 if ((id
= get_composition_id (pos
, pos_byte
, end
- pos
, prop
, Qnil
)) < 0)
303 *len
= COMPOSITION_LENGTH (prop
);
304 *len_byte
= CHAR_TO_BYTE (end
) - pos_byte
;
305 *width
= composition_table
[id
]->width
;
309 /* Set variables WIDTH and BYTES for a multibyte sequence starting at P.
311 DP is a display table or NULL.
313 This macro is used in current_column_1, Fmove_to_column, and
316 #define MULTIBYTE_BYTES_WIDTH(p, dp) \
321 c = STRING_CHAR_AND_LENGTH (p, MAX_MULTIBYTE_LENGTH, bytes); \
322 if (BYTES_BY_CHAR_HEAD (*p) != bytes) \
326 if (dp != 0 && VECTORP (DISP_CHAR_VECTOR (dp, c))) \
327 width = XVECTOR (DISP_CHAR_VECTOR (dp, c))->size; \
329 width = WIDTH_BY_CHAR_HEAD (*p); \
331 wide_column = width; \
336 DEFUN ("current-column", Fcurrent_column
, Scurrent_column
, 0, 0, 0,
337 doc
: /* Return the horizontal position of point. Beginning of line is column 0.
338 This is calculated by adding together the widths of all the displayed
339 representations of the character between the start of the previous line
340 and point (eg. control characters will have a width of 2 or 4, tabs
341 will have a variable width).
342 Ignores finite width of frame, which means that this function may return
343 values greater than (frame-width).
344 Whether the line is visible (if `selective-display' is t) has no effect;
345 however, ^M is treated as end of line when `selective-display' is t.
346 Text that has an invisible property is considered as having width 0, unless
347 `buffer-invisibility-spec' specifies that it is replaced by an ellipsis. */)
351 XSETFASTINT (temp
, (int) current_column ()); /* iftc */
355 /* Cancel any recorded value of the horizontal position. */
358 invalidate_current_column ()
360 last_known_column_point
= 0;
367 register unsigned char *ptr
, *stop
;
368 register int tab_seen
;
371 register int tab_width
= XINT (current_buffer
->tab_width
);
372 int ctl_arrow
= !NILP (current_buffer
->ctl_arrow
);
373 register struct Lisp_Char_Table
*dp
= buffer_display_table ();
375 if (PT
== last_known_column_point
376 && MODIFF
== last_known_column_modified
)
377 return last_known_column
;
379 /* If the buffer has overlays, text properties,
380 or multibyte characters, use a more general algorithm. */
381 if (BUF_INTERVALS (current_buffer
)
382 || current_buffer
->overlays_before
383 || current_buffer
->overlays_after
385 return current_column_1 ();
387 /* Scan backwards from point to the previous newline,
388 counting width. Tab characters are the only complicated case. */
390 /* Make a pointer for decrementing through the chars before point. */
391 ptr
= BYTE_POS_ADDR (PT_BYTE
- 1) + 1;
392 /* Make a pointer to where consecutive chars leave off,
393 going backwards from point. */
396 else if (PT
<= GPT
|| BEGV
> GPT
)
401 if (tab_width
<= 0 || tab_width
> 1000)
404 col
= 0, tab_seen
= 0, post_tab
= 0;
413 /* We stopped either for the beginning of the buffer
415 if (ptr
== BEGV_ADDR
)
418 /* It was the gap. Jump back over it. */
422 /* Check whether that brings us to beginning of buffer. */
429 if (dp
&& VECTORP (DISP_CHAR_VECTOR (dp
, c
)))
431 charvec
= DISP_CHAR_VECTOR (dp
, c
);
440 for (i
= n
- 1; i
>= 0; --i
)
442 if (VECTORP (charvec
))
444 /* This should be handled the same as
445 next_element_from_display_vector does it. */
446 Lisp_Object entry
= AREF (charvec
, i
);
449 && GLYPH_CHAR_VALID_P (XFASTINT (entry
)))
450 c
= FAST_GLYPH_CHAR (XFASTINT (entry
));
455 if (c
>= 040 && c
< 0177)
459 && EQ (current_buffer
->selective_display
, Qt
)))
462 goto start_of_line_found
;
467 col
= ((col
+ tab_width
) / tab_width
) * tab_width
;
473 else if (VECTORP (charvec
))
474 /* With a display table entry, C is displayed as is, and
475 not displayed as \NNN or as ^N. If C is a single-byte
476 character, it takes one column. If C is multi-byte in
477 an unibyte buffer, it's translated to unibyte, so it
478 also takes one column. */
481 col
+= (ctl_arrow
&& c
< 0200) ? 2 : 4;
489 col
= ((col
+ tab_width
) / tab_width
) * tab_width
;
493 if (ptr
== BEGV_ADDR
)
494 current_column_bol_cache
= BEGV
;
496 current_column_bol_cache
= BYTE_TO_CHAR (PTR_BYTE_POS (ptr
));
498 last_known_column
= col
;
499 last_known_column_point
= PT
;
500 last_known_column_modified
= MODIFF
;
505 /* Return the column number of position POS
506 by scanning forward from the beginning of the line.
507 This function handles characters that are invisible
508 due to text properties or overlays. */
513 register int tab_width
= XINT (current_buffer
->tab_width
);
514 register int ctl_arrow
= !NILP (current_buffer
->ctl_arrow
);
515 register struct Lisp_Char_Table
*dp
= buffer_display_table ();
516 int multibyte
= !NILP (current_buffer
->enable_multibyte_characters
);
518 /* Start the scan at the beginning of this line with column number 0. */
519 register int col
= 0;
522 int opoint
= PT
, opoint_byte
= PT_BYTE
;
524 scan_newline (PT
, PT_BYTE
, BEGV
, BEGV_BYTE
, -1, 1);
525 current_column_bol_cache
= PT
;
526 scan
= PT
, scan_byte
= PT_BYTE
;
527 SET_PT_BOTH (opoint
, opoint_byte
);
528 next_boundary
= scan
;
530 if (tab_width
<= 0 || tab_width
> 1000) tab_width
= 8;
532 /* Scan forward to the target position. */
533 while (scan
< opoint
)
537 /* Occasionally we may need to skip invisible text. */
538 while (scan
== next_boundary
)
541 /* This updates NEXT_BOUNDARY to the next place
542 where we might need to skip more invisible text. */
543 scan
= skip_invisible (scan
, &next_boundary
, opoint
, Qnil
);
546 if (scan
!= old_scan
)
547 scan_byte
= CHAR_TO_BYTE (scan
);
550 /* Check composition sequence. */
552 int len
, len_byte
, width
;
554 if (check_composition (scan
, scan_byte
, opoint
,
555 &len
, &len_byte
, &width
))
558 scan_byte
+= len_byte
;
565 c
= FETCH_BYTE (scan_byte
);
568 && ! (multibyte
&& BASE_LEADING_CODE_P (c
))
569 && VECTORP (DISP_CHAR_VECTOR (dp
, c
)))
574 /* This character is displayed using a vector of glyphs.
575 Update the column based on those glyphs. */
577 charvec
= DISP_CHAR_VECTOR (dp
, c
);
580 for (i
= 0; i
< n
; i
++)
582 /* This should be handled the same as
583 next_element_from_display_vector does it. */
585 entry
= AREF (charvec
, i
);
588 && GLYPH_CHAR_VALID_P (XFASTINT (entry
)))
589 c
= FAST_GLYPH_CHAR (XFASTINT (entry
));
595 if (c
== '\r' && EQ (current_buffer
->selective_display
, Qt
))
600 col
= col
/ tab_width
* tab_width
;
608 /* The display table says nothing for this character.
609 Display it as itself. */
613 if (c
== '\r' && EQ (current_buffer
->selective_display
, Qt
))
618 col
= col
/ tab_width
* tab_width
;
620 else if (multibyte
&& BASE_LEADING_CODE_P (c
))
623 int bytes
, width
, wide_column
;
625 ptr
= BYTE_POS_ADDR (scan_byte
);
626 MULTIBYTE_BYTES_WIDTH (ptr
, dp
);
628 /* Subtract one to compensate for the increment
629 that is going to happen below. */
633 else if (ctl_arrow
&& (c
< 040 || c
== 0177))
635 else if (c
< 040 || c
>= 0177)
646 last_known_column
= col
;
647 last_known_column_point
= PT
;
648 last_known_column_modified
= MODIFF
;
654 #if 0 /* Not used. */
656 /* Return the width in columns of the part of STRING from BEG to END.
657 If BEG is nil, that stands for the beginning of STRING.
658 If END is nil, that stands for the end of STRING. */
661 string_display_width (string
, beg
, end
)
662 Lisp_Object string
, beg
, end
;
665 register unsigned char *ptr
, *stop
;
666 register int tab_seen
;
669 register int tab_width
= XINT (current_buffer
->tab_width
);
670 int ctl_arrow
= !NILP (current_buffer
->ctl_arrow
);
671 register struct Lisp_Char_Table
*dp
= buffer_display_table ();
690 /* Make a pointer for decrementing through the chars before point. */
691 ptr
= SDATA (string
) + e
;
692 /* Make a pointer to where consecutive chars leave off,
693 going backwards from point. */
694 stop
= SDATA (string
) + b
;
696 if (tab_width
<= 0 || tab_width
> 1000) tab_width
= 8;
698 col
= 0, tab_seen
= 0, post_tab
= 0;
706 if (dp
!= 0 && VECTORP (DISP_CHAR_VECTOR (dp
, c
)))
707 col
+= XVECTOR (DISP_CHAR_VECTOR (dp
, c
))->size
;
708 else if (c
>= 040 && c
< 0177)
715 col
= ((col
+ tab_width
) / tab_width
) * tab_width
;
722 col
+= (ctl_arrow
&& c
< 0200) ? 2 : 4;
727 col
= ((col
+ tab_width
) / tab_width
) * tab_width
;
737 DEFUN ("indent-to", Findent_to
, Sindent_to
, 1, 2, "NIndent to column: ",
738 doc
: /* Indent from point with tabs and spaces until COLUMN is reached.
739 Optional second argument MINIMUM says always do at least MINIMUM spaces
740 even if that goes past COLUMN; by default, MINIMUM is zero.
742 The return value is COLUMN. */)
744 Lisp_Object column
, minimum
;
747 register int fromcol
;
748 register int tab_width
= XINT (current_buffer
->tab_width
);
750 CHECK_NUMBER (column
);
752 XSETFASTINT (minimum
, 0);
753 CHECK_NUMBER (minimum
);
755 fromcol
= current_column ();
756 mincol
= fromcol
+ XINT (minimum
);
757 if (mincol
< XINT (column
)) mincol
= XINT (column
);
759 if (fromcol
== mincol
)
760 return make_number (mincol
);
762 if (tab_width
<= 0 || tab_width
> 1000) tab_width
= 8;
764 if (indent_tabs_mode
)
767 XSETFASTINT (n
, mincol
/ tab_width
- fromcol
/ tab_width
);
768 if (XFASTINT (n
) != 0)
770 Finsert_char (make_number ('\t'), n
, Qt
);
772 fromcol
= (mincol
/ tab_width
) * tab_width
;
776 XSETFASTINT (column
, mincol
- fromcol
);
777 Finsert_char (make_number (' '), column
, Qt
);
779 last_known_column
= mincol
;
780 last_known_column_point
= PT
;
781 last_known_column_modified
= MODIFF
;
783 XSETINT (column
, mincol
);
788 static double position_indentation
P_ ((int));
790 DEFUN ("current-indentation", Fcurrent_indentation
, Scurrent_indentation
,
792 doc
: /* Return the indentation of the current line.
793 This is the horizontal position of the character
794 following any initial whitespace. */)
798 int opoint
= PT
, opoint_byte
= PT_BYTE
;
800 scan_newline (PT
, PT_BYTE
, BEGV
, BEGV_BYTE
, -1, 1);
802 XSETFASTINT (val
, (int) position_indentation (PT_BYTE
)); /* iftc */
803 SET_PT_BOTH (opoint
, opoint_byte
);
808 position_indentation (pos_byte
)
809 register int pos_byte
;
811 register int column
= 0;
812 register int tab_width
= XINT (current_buffer
->tab_width
);
813 register unsigned char *p
;
814 register unsigned char *stop
;
815 unsigned char *start
;
816 int next_boundary_byte
= pos_byte
;
817 int ceiling
= next_boundary_byte
;
819 if (tab_width
<= 0 || tab_width
> 1000) tab_width
= 8;
821 p
= BYTE_POS_ADDR (pos_byte
);
822 /* STOP records the value of P at which we will need
823 to think about the gap, or about invisible text,
824 or about the end of the buffer. */
826 /* START records the starting value of P. */
834 /* If we have updated P, set POS_BYTE to match.
835 The first time we enter the loop, POS_BYTE is already right. */
837 pos_byte
= PTR_BYTE_POS (p
);
838 /* Consider the various reasons STOP might have been set here. */
839 if (pos_byte
== ZV_BYTE
)
841 if (pos_byte
== next_boundary_byte
)
844 int pos
= BYTE_TO_CHAR (pos_byte
);
845 pos
= skip_invisible (pos
, &next_boundary
, ZV
, Qnil
);
846 pos_byte
= CHAR_TO_BYTE (pos
);
847 next_boundary_byte
= CHAR_TO_BYTE (next_boundary
);
849 if (pos_byte
>= ceiling
)
850 ceiling
= BUFFER_CEILING_OF (pos_byte
) + 1;
851 /* Compute the next place we need to stop and think,
852 and set STOP accordingly. */
853 stop_pos_byte
= min (ceiling
, next_boundary_byte
);
854 /* The -1 and +1 arrange to point at the first byte of gap
855 (if STOP_POS_BYTE is the position of the gap)
856 rather than at the data after the gap. */
858 stop
= BYTE_POS_ADDR (stop_pos_byte
- 1) + 1;
859 p
= BYTE_POS_ADDR (pos_byte
);
864 if (! NILP (current_buffer
->enable_multibyte_characters
))
870 column
+= tab_width
- column
% tab_width
;
873 if (ASCII_BYTE_P (p
[-1])
874 || NILP (current_buffer
->enable_multibyte_characters
))
878 pos_byte
= PTR_BYTE_POS (p
- 1);
879 c
= FETCH_MULTIBYTE_CHAR (pos_byte
);
880 if (CHAR_HAS_CATEGORY (c
, ' '))
884 p
= BYTE_POS_ADDR (pos_byte
);
893 /* Test whether the line beginning at POS is indented beyond COLUMN.
894 Blank lines are treated as if they had the same indentation as the
898 indented_beyond_p (pos
, pos_byte
, column
)
903 int opoint
= PT
, opoint_byte
= PT_BYTE
;
905 SET_PT_BOTH (pos
, pos_byte
);
906 while (PT
> BEGV
&& FETCH_BYTE (PT_BYTE
) == '\n')
907 scan_newline (PT
- 1, PT_BYTE
- 1, BEGV
, BEGV_BYTE
, -1, 0);
909 val
= position_indentation (PT_BYTE
);
910 SET_PT_BOTH (opoint
, opoint_byte
);
911 return val
>= column
; /* hmm, float comparison */
914 DEFUN ("move-to-column", Fmove_to_column
, Smove_to_column
, 1, 2, "p",
915 doc
: /* Move point to column COLUMN in the current line.
916 Interactively, COLUMN is the value of prefix numeric argument.
917 The column of a character is calculated by adding together the widths
918 as displayed of the previous characters in the line.
919 This function ignores line-continuation;
920 there is no upper limit on the column number a character can have
921 and horizontal scrolling has no effect.
923 If specified column is within a character, point goes after that character.
924 If it's past end of line, point goes to end of line.
926 Optional second argument FORCE non-nil means if COLUMN is in the
927 middle of a tab character, change it to spaces.
928 In addition, if FORCE is t, and the line is too short to reach
929 COLUMN, add spaces/tabs to get there.
931 The return value is the current column. */)
933 Lisp_Object column
, force
;
936 register int col
= current_column ();
939 register int tab_width
= XINT (current_buffer
->tab_width
);
940 register int ctl_arrow
= !NILP (current_buffer
->ctl_arrow
);
941 register struct Lisp_Char_Table
*dp
= buffer_display_table ();
942 register int multibyte
= !NILP (current_buffer
->enable_multibyte_characters
);
947 int next_boundary
, pos_byte
;
949 if (tab_width
<= 0 || tab_width
> 1000) tab_width
= 8;
950 CHECK_NATNUM (column
);
951 goal
= XINT (column
);
957 /* If we're starting past the desired column,
958 back up to beginning of line and scan from there. */
962 pos
= current_column_bol_cache
;
963 pos_byte
= CHAR_TO_BYTE (pos
);
971 while (pos
== next_boundary
)
974 pos
= skip_invisible (pos
, &next_boundary
, end
, Qnil
);
976 pos_byte
= CHAR_TO_BYTE (pos
);
981 /* Test reaching the goal column. We do this after skipping
982 invisible characters, so that we put point before the
983 character on which the cursor will appear. */
987 /* Check composition sequence. */
989 int len
, len_byte
, width
;
991 if (check_composition (pos
, pos_byte
, Z
, &len
, &len_byte
, &width
))
994 pos_byte
+= len_byte
;
1000 c
= FETCH_BYTE (pos_byte
);
1002 /* See if there is a display table and it relates
1003 to this character. */
1006 && ! (multibyte
&& BASE_LEADING_CODE_P (c
))
1007 && VECTORP (DISP_CHAR_VECTOR (dp
, c
)))
1009 Lisp_Object charvec
;
1012 /* This character is displayed using a vector of glyphs.
1013 Update the position based on those glyphs. */
1015 charvec
= DISP_CHAR_VECTOR (dp
, c
);
1016 n
= ASIZE (charvec
);
1018 for (i
= 0; i
< n
; i
++)
1020 /* This should be handled the same as
1021 next_element_from_display_vector does it. */
1024 entry
= AREF (charvec
, i
);
1026 if (INTEGERP (entry
)
1027 && GLYPH_CHAR_VALID_P (XFASTINT (entry
)))
1028 c
= FAST_GLYPH_CHAR (XFASTINT (entry
));
1034 if (c
== '\r' && EQ (current_buffer
->selective_display
, Qt
))
1040 col
= col
/ tab_width
* tab_width
;
1048 /* The display table doesn't affect this character;
1049 it displays as itself. */
1053 if (c
== '\r' && EQ (current_buffer
->selective_display
, Qt
))
1059 col
= col
/ tab_width
* tab_width
;
1061 else if (ctl_arrow
&& (c
< 040 || c
== 0177))
1063 else if (c
< 040 || c
== 0177)
1067 else if (multibyte
&& BASE_LEADING_CODE_P (c
))
1069 /* Start of multi-byte form. */
1071 int bytes
, width
, wide_column
;
1073 ptr
= BYTE_POS_ADDR (pos_byte
);
1074 MULTIBYTE_BYTES_WIDTH (ptr
, dp
);
1075 pos_byte
+= bytes
- 1;
1087 SET_PT_BOTH (pos
, pos_byte
);
1089 /* If a tab char made us overshoot, change it to spaces
1090 and scan through it again. */
1091 if (!NILP (force
) && col
> goal
&& c
== '\t' && prev_col
< goal
)
1093 int goal_pt
, goal_pt_byte
;
1095 /* Insert spaces in front of the tab to reach GOAL. Do this
1096 first so that a marker at the end of the tab gets
1098 SET_PT_BOTH (PT
- 1, PT_BYTE
- 1);
1099 Finsert_char (make_number (' '), make_number (goal
- prev_col
), Qt
);
1101 /* Now delete the tab, and indent to COL. */
1102 del_range (PT
, PT
+ 1);
1104 goal_pt_byte
= PT_BYTE
;
1105 Findent_to (make_number (col
), Qnil
);
1106 SET_PT_BOTH (goal_pt
, goal_pt_byte
);
1108 /* Set the last_known... vars consistently. */
1112 /* If line ends prematurely, add space to the end. */
1113 if (col
< goal
&& EQ (force
, Qt
))
1114 Findent_to (make_number (col
= goal
), Qnil
);
1116 last_known_column
= col
;
1117 last_known_column_point
= PT
;
1118 last_known_column_modified
= MODIFF
;
1120 XSETFASTINT (val
, col
);
1124 /* compute_motion: compute buffer posn given screen posn and vice versa */
1126 struct position val_compute_motion
;
1128 /* Scan the current buffer forward from offset FROM, pretending that
1129 this is at line FROMVPOS, column FROMHPOS, until reaching buffer
1130 offset TO or line TOVPOS, column TOHPOS (whichever comes first),
1131 and return the ending buffer position and screen location. If we
1132 can't hit the requested column exactly (because of a tab or other
1133 multi-column character), overshoot.
1135 DID_MOTION is 1 if FROMHPOS has already accounted for overlay strings
1136 at FROM. This is the case if FROMVPOS and FROMVPOS came from an
1137 earlier call to compute_motion. The other common case is that FROMHPOS
1138 is zero and FROM is a position that "belongs" at column zero, but might
1139 be shifted by overlay strings; in this case DID_MOTION should be 0.
1141 WIDTH is the number of columns available to display text;
1142 compute_motion uses this to handle continuation lines and such.
1143 If WIDTH is -1, use width of window's text area adjusted for
1144 continuation glyph when needed.
1146 HSCROLL is the number of columns not being displayed at the left
1147 margin; this is usually taken from a window's hscroll member.
1148 TAB_OFFSET is the number of columns of the first tab that aren't
1149 being displayed, perhaps because of a continuation line or
1152 compute_motion returns a pointer to a struct position. The bufpos
1153 member gives the buffer position at the end of the scan, and hpos
1154 and vpos give its cartesian location. prevhpos is the column at
1155 which the character before bufpos started, and contin is non-zero
1156 if we reached the current line by continuing the previous.
1158 Note that FROMHPOS and TOHPOS should be expressed in real screen
1159 columns, taking HSCROLL and the truncation glyph at the left margin
1160 into account. That is, beginning-of-line moves you to the hpos
1161 -HSCROLL + (HSCROLL > 0).
1163 For example, to find the buffer position of column COL of line LINE
1164 of a certain window, pass the window's starting location as FROM
1165 and the window's upper-left coordinates as FROMVPOS and FROMHPOS.
1166 Pass the buffer's ZV as TO, to limit the scan to the end of the
1167 visible section of the buffer, and pass LINE and COL as TOVPOS and
1170 When displaying in window w, a typical formula for WIDTH is:
1173 - (has_vertical_scroll_bars
1174 ? WINDOW_CONFIG_SCROLL_BAR_COLS (window)
1175 : (window_width + window_left != frame_cols))
1178 window_width is XFASTINT (w->total_cols),
1179 window_left is XFASTINT (w->left_col),
1180 has_vertical_scroll_bars is
1181 WINDOW_HAS_VERTICAL_SCROLL_BAR (window)
1182 and frame_cols = FRAME_COLS (XFRAME (window->frame))
1184 Or you can let window_box_text_cols do this all for you, and write:
1185 window_box_text_cols (w) - 1
1187 The `-1' accounts for the continuation-line backslashes; the rest
1188 accounts for window borders if the window is split horizontally, and
1189 the scroll bars if they are turned on. */
1192 compute_motion (from
, fromvpos
, fromhpos
, did_motion
, to
, tovpos
, tohpos
, width
, hscroll
, tab_offset
, win
)
1193 int from
, fromvpos
, fromhpos
, to
, tovpos
, tohpos
;
1196 int hscroll
, tab_offset
;
1199 register int hpos
= fromhpos
;
1200 register int vpos
= fromvpos
;
1205 register int tab_width
= XFASTINT (current_buffer
->tab_width
);
1206 register int ctl_arrow
= !NILP (current_buffer
->ctl_arrow
);
1207 register struct Lisp_Char_Table
*dp
= window_display_table (win
);
1209 = (INTEGERP (current_buffer
->selective_display
)
1210 ? XINT (current_buffer
->selective_display
)
1211 : !NILP (current_buffer
->selective_display
) ? -1 : 0);
1213 = (selective
&& dp
&& VECTORP (DISP_INVIS_VECTOR (dp
))
1214 ? XVECTOR (DISP_INVIS_VECTOR (dp
))->size
: 0);
1215 /* The next location where the `invisible' property changes, or an
1216 overlay starts or ends. */
1217 int next_boundary
= from
;
1219 /* For computing runs of characters with similar widths.
1220 Invariant: width_run_width is zero, or all the characters
1221 from width_run_start to width_run_end have a fixed width of
1223 int width_run_start
= from
;
1224 int width_run_end
= from
;
1225 int width_run_width
= 0;
1226 Lisp_Object
*width_table
;
1229 /* The next buffer pos where we should consult the width run cache. */
1230 int next_width_run
= from
;
1233 int multibyte
= !NILP (current_buffer
->enable_multibyte_characters
);
1234 /* If previous char scanned was a wide character,
1235 this is the column where it ended. Otherwise, this is 0. */
1236 int wide_column_end_hpos
= 0;
1237 int prev_pos
; /* Previous buffer position. */
1238 int prev_pos_byte
; /* Previous buffer position. */
1241 int contin_hpos
; /* HPOS of last column of continued line. */
1242 int prev_tab_offset
; /* Previous tab offset. */
1243 int continuation_glyph_width
;
1245 XSETBUFFER (buffer
, current_buffer
);
1246 XSETWINDOW (window
, win
);
1248 width_run_cache_on_off ();
1249 if (dp
== buffer_display_table ())
1250 width_table
= (VECTORP (current_buffer
->width_table
)
1251 ? XVECTOR (current_buffer
->width_table
)->contents
1254 /* If the window has its own display table, we can't use the width
1255 run cache, because that's based on the buffer's display table. */
1258 if (tab_width
<= 0 || tab_width
> 1000)
1261 /* Negative width means use all available text columns. */
1264 width
= window_box_text_cols (win
);
1265 /* We must make room for continuation marks if we don't have fringes. */
1266 #ifdef HAVE_WINDOW_SYSTEM
1267 if (!FRAME_WINDOW_P (XFRAME (win
->frame
)))
1272 continuation_glyph_width
= 1;
1273 #ifdef HAVE_WINDOW_SYSTEM
1274 if (FRAME_WINDOW_P (XFRAME (win
->frame
)))
1275 continuation_glyph_width
= 0; /* In the fringe. */
1281 pos
= prev_pos
= from
;
1282 pos_byte
= prev_pos_byte
= CHAR_TO_BYTE (from
);
1284 prev_tab_offset
= tab_offset
;
1287 while (pos
== next_boundary
)
1292 /* Don't skip invisible if we are already at the margin. */
1293 if (vpos
> tovpos
|| (vpos
== tovpos
&& hpos
>= tohpos
))
1295 if (contin_hpos
&& prev_hpos
== 0
1297 && (contin_hpos
== width
|| wide_column_end_hpos
> width
))
1298 { /* Line breaks because we can't put the character at the
1299 previous line any more. It is not the multi-column
1300 character continued in middle. Go back to previous
1301 buffer position, screen position, and set tab offset
1302 to previous value. It's the beginning of the
1305 pos_byte
= prev_pos_byte
;
1308 tab_offset
= prev_tab_offset
;
1313 /* If the caller says that the screen position came from an earlier
1314 call to compute_motion, then we've already accounted for the
1315 overlay strings at point. This is only true the first time
1316 through, so clear the flag after testing it. */
1318 /* We need to skip past the overlay strings. Currently those
1319 strings must not contain TAB;
1320 if we want to relax that restriction, something will have
1321 to be changed here. */
1323 unsigned char *ovstr
;
1324 int ovlen
= overlay_strings (pos
, win
, &ovstr
);
1325 hpos
+= ((multibyte
&& ovlen
> 0)
1326 ? strwidth (ovstr
, ovlen
) : ovlen
);
1333 /* Advance POS past invisible characters
1334 (but not necessarily all that there are here),
1335 and store in next_boundary the next position where
1336 we need to call skip_invisible. */
1337 newpos
= skip_invisible (pos
, &next_boundary
, to
, window
);
1341 pos
= min (to
, newpos
);
1342 pos_byte
= CHAR_TO_BYTE (pos
);
1346 if (newpos
!= pos_here
)
1349 pos_byte
= CHAR_TO_BYTE (pos
);
1353 /* Handle right margin. */
1354 /* Note on a wide-column character.
1356 Characters are classified into the following three categories
1357 according to the width (columns occupied on screen).
1359 (1) single-column character: ex. `a'
1360 (2) multi-column character: ex. `^A', TAB, `\033'
1361 (3) wide-column character: ex. Japanese character, Chinese character
1362 (In the following example, `W_' stands for them.)
1364 Multi-column characters can be divided around the right margin,
1365 but wide-column characters cannot.
1369 (*) The cursor is placed on the next character after the point.
1373 j ^---- next after the point
1374 ^--- next char. after the point.
1376 In case of sigle-column character
1380 033 ^---- next after the point, next char. after the point.
1382 In case of multi-column character
1386 W_ ^---- next after the point
1387 ^---- next char. after the point.
1389 In case of wide-column character
1391 The problem here is continuation at a wide-column character.
1392 In this case, the line may shorter less than WIDTH.
1393 And we find the continuation AFTER it occurs.
1400 || (truncate_partial_width_windows
1401 && ((width
+ continuation_glyph_width
)
1402 < FRAME_COLS (XFRAME (WINDOW_FRAME (win
)))))
1403 || !NILP (current_buffer
->truncate_lines
))
1405 /* Truncating: skip to newline, unless we are already past
1406 TO (we need to go back below). */
1409 pos
= find_before_next_newline (pos
, to
, 1);
1410 pos_byte
= CHAR_TO_BYTE (pos
);
1412 /* If we just skipped next_boundary,
1413 loop around in the main while
1415 if (pos
>= next_boundary
)
1416 next_boundary
= pos
+ 1;
1419 prev_tab_offset
= tab_offset
;
1425 /* Remember the previous value. */
1426 prev_tab_offset
= tab_offset
;
1428 if (wide_column_end_hpos
> width
)
1431 tab_offset
+= prev_hpos
;
1435 tab_offset
+= width
;
1439 contin_hpos
= prev_hpos
;
1445 /* Stop if past the target buffer position or screen position. */
1448 /* Go back to the previous position. */
1450 pos_byte
= prev_pos_byte
;
1453 tab_offset
= prev_tab_offset
;
1455 /* NOTE on contin_hpos, hpos, and prev_hpos.
1459 W_ ^---- contin_hpos
1465 if (contin_hpos
&& prev_hpos
== 0
1466 && contin_hpos
< width
&& !wide_column_end_hpos
)
1468 /* Line breaking occurs in the middle of multi-column
1469 character. Go back to previous line. */
1476 if (vpos
> tovpos
|| (vpos
== tovpos
&& hpos
>= tohpos
))
1478 if (contin_hpos
&& prev_hpos
== 0
1480 && (contin_hpos
== width
|| wide_column_end_hpos
> width
))
1481 { /* Line breaks because we can't put the character at the
1482 previous line any more. It is not the multi-column
1483 character continued in middle. Go back to previous
1484 buffer position, screen position, and set tab offset
1485 to previous value. It's the beginning of the
1488 pos_byte
= prev_pos_byte
;
1491 tab_offset
= prev_tab_offset
;
1495 if (pos
== ZV
) /* We cannot go beyond ZV. Stop here. */
1501 prev_pos_byte
= pos_byte
;
1502 wide_column_end_hpos
= 0;
1504 /* Consult the width run cache to see if we can avoid inspecting
1505 the text character-by-character. */
1506 if (current_buffer
->width_run_cache
&& pos
>= next_width_run
)
1510 = region_cache_forward (current_buffer
,
1511 current_buffer
->width_run_cache
,
1514 /* A width of zero means the character's width varies (like
1515 a tab), is meaningless (like a newline), or we just don't
1516 want to skip over it for some other reason. */
1517 if (common_width
!= 0)
1521 /* Don't go past the final buffer posn the user
1526 run_end_hpos
= hpos
+ (run_end
- pos
) * common_width
;
1528 /* Don't go past the final horizontal position the user
1530 if (vpos
== tovpos
&& run_end_hpos
> tohpos
)
1532 run_end
= pos
+ (tohpos
- hpos
) / common_width
;
1533 run_end_hpos
= hpos
+ (run_end
- pos
) * common_width
;
1536 /* Don't go past the margin. */
1537 if (run_end_hpos
>= width
)
1539 run_end
= pos
+ (width
- hpos
) / common_width
;
1540 run_end_hpos
= hpos
+ (run_end
- pos
) * common_width
;
1543 hpos
= run_end_hpos
;
1545 prev_hpos
= hpos
- common_width
;
1549 pos_byte
= CHAR_TO_BYTE (pos
);
1553 next_width_run
= run_end
+ 1;
1556 /* We have to scan the text character-by-character. */
1560 Lisp_Object charvec
;
1562 c
= FETCH_BYTE (pos_byte
);
1564 /* Check composition sequence. */
1566 int len
, len_byte
, width
;
1568 if (check_composition (pos
, pos_byte
, to
, &len
, &len_byte
, &width
))
1571 pos_byte
+= len_byte
;
1579 /* Perhaps add some info to the width_run_cache. */
1580 if (current_buffer
->width_run_cache
)
1582 /* Is this character part of the current run? If so, extend
1584 if (pos
- 1 == width_run_end
1585 && XFASTINT (width_table
[c
]) == width_run_width
)
1586 width_run_end
= pos
;
1588 /* The previous run is over, since this is a character at a
1589 different position, or a different width. */
1592 /* Have we accumulated a run to put in the cache?
1593 (Currently, we only cache runs of width == 1). */
1594 if (width_run_start
< width_run_end
1595 && width_run_width
== 1)
1596 know_region_cache (current_buffer
,
1597 current_buffer
->width_run_cache
,
1598 width_run_start
, width_run_end
);
1600 /* Start recording a new width run. */
1601 width_run_width
= XFASTINT (width_table
[c
]);
1602 width_run_start
= pos
- 1;
1603 width_run_end
= pos
;
1608 && ! (multibyte
&& BASE_LEADING_CODE_P (c
))
1609 && VECTORP (DISP_CHAR_VECTOR (dp
, c
)))
1611 charvec
= DISP_CHAR_VECTOR (dp
, c
);
1612 n
= ASIZE (charvec
);
1620 for (i
= n
- 1; i
>= 0; --i
)
1622 if (VECTORP (charvec
))
1624 /* This should be handled the same as
1625 next_element_from_display_vector does it. */
1626 Lisp_Object entry
= AREF (charvec
, i
);
1628 if (INTEGERP (entry
)
1629 && GLYPH_CHAR_VALID_P (XFASTINT (entry
)))
1630 c
= FAST_GLYPH_CHAR (XFASTINT (entry
));
1635 if (c
>= 040 && c
< 0177)
1639 int tem
= ((hpos
+ tab_offset
+ hscroll
- (hscroll
> 0))
1643 hpos
+= tab_width
- tem
;
1648 && indented_beyond_p (pos
, pos_byte
,
1649 (double) selective
)) /* iftc */
1651 /* If (pos == to), we don't have to take care of
1652 selective display. */
1655 /* Skip any number of invisible lines all at once */
1658 pos
= find_before_next_newline (pos
, to
, 1);
1661 pos_byte
= CHAR_TO_BYTE (pos
);
1664 && indented_beyond_p (pos
, pos_byte
,
1665 (double) selective
)); /* iftc */
1666 /* Allow for the " ..." that is displayed for them. */
1669 hpos
+= selective_rlen
;
1673 DEC_BOTH (pos
, pos_byte
);
1674 /* We have skipped the invis text, but not the
1680 /* A visible line. */
1684 /* Count the truncation glyph on column 0 */
1686 hpos
+= continuation_glyph_width
;
1691 else if (c
== CR
&& selective
< 0)
1693 /* In selective display mode,
1694 everything from a ^M to the end of the line is invisible.
1695 Stop *before* the real newline. */
1698 pos
= find_before_next_newline (pos
, to
, 1);
1699 pos_byte
= CHAR_TO_BYTE (pos
);
1701 /* If we just skipped next_boundary,
1702 loop around in the main while
1704 if (pos
> next_boundary
)
1705 next_boundary
= pos
;
1706 /* Allow for the " ..." that is displayed for them. */
1709 hpos
+= selective_rlen
;
1714 else if (multibyte
&& BASE_LEADING_CODE_P (c
))
1716 /* Start of multi-byte form. */
1718 int bytes
, width
, wide_column
;
1720 pos_byte
--; /* rewind POS_BYTE */
1721 ptr
= BYTE_POS_ADDR (pos_byte
);
1722 MULTIBYTE_BYTES_WIDTH (ptr
, dp
);
1725 wide_column_end_hpos
= hpos
+ wide_column
;
1728 else if (VECTORP (charvec
))
1731 hpos
+= (ctl_arrow
&& c
< 0200) ? 2 : 4;
1738 /* Remember any final width run in the cache. */
1739 if (current_buffer
->width_run_cache
1740 && width_run_width
== 1
1741 && width_run_start
< width_run_end
)
1742 know_region_cache (current_buffer
, current_buffer
->width_run_cache
,
1743 width_run_start
, width_run_end
);
1745 val_compute_motion
.bufpos
= pos
;
1746 val_compute_motion
.bytepos
= pos_byte
;
1747 val_compute_motion
.hpos
= hpos
;
1748 val_compute_motion
.vpos
= vpos
;
1749 if (contin_hpos
&& prev_hpos
== 0)
1750 val_compute_motion
.prevhpos
= contin_hpos
;
1752 val_compute_motion
.prevhpos
= prev_hpos
;
1753 /* We alalways handle all of them here; none of them remain to do. */
1754 val_compute_motion
.ovstring_chars_done
= 0;
1756 /* Nonzero if have just continued a line */
1757 val_compute_motion
.contin
= (contin_hpos
&& prev_hpos
== 0);
1760 return &val_compute_motion
;
1764 DEFUN ("compute-motion", Fcompute_motion
, Scompute_motion
, 7, 7, 0,
1765 doc
: /* Scan through the current buffer, calculating screen position.
1766 Scan the current buffer forward from offset FROM,
1767 assuming it is at position FROMPOS--a cons of the form (HPOS . VPOS)--
1768 to position TO or position TOPOS--another cons of the form (HPOS . VPOS)--
1769 and return the ending buffer position and screen location.
1771 If TOPOS is nil, the actual width and height of the window's
1774 There are three additional arguments:
1776 WIDTH is the number of columns available to display text;
1777 this affects handling of continuation lines. A value of nil
1778 corresponds to the actual number of available text columns.
1780 OFFSETS is either nil or a cons cell (HSCROLL . TAB-OFFSET).
1781 HSCROLL is the number of columns not being displayed at the left
1782 margin; this is usually taken from a window's hscroll member.
1783 TAB-OFFSET is the number of columns of the first tab that aren't
1784 being displayed, perhaps because the line was continued within it.
1785 If OFFSETS is nil, HSCROLL and TAB-OFFSET are assumed to be zero.
1787 WINDOW is the window to operate on. It is used to choose the display table;
1788 if it is showing the current buffer, it is used also for
1789 deciding which overlay properties apply.
1790 Note that `compute-motion' always operates on the current buffer.
1792 The value is a list of five elements:
1793 (POS HPOS VPOS PREVHPOS CONTIN)
1794 POS is the buffer position where the scan stopped.
1795 VPOS is the vertical position where the scan stopped.
1796 HPOS is the horizontal position where the scan stopped.
1798 PREVHPOS is the horizontal position one character back from POS.
1799 CONTIN is t if a line was continued after (or within) the previous character.
1801 For example, to find the buffer position of column COL of line LINE
1802 of a certain window, pass the window's starting location as FROM
1803 and the window's upper-left coordinates as FROMPOS.
1804 Pass the buffer's (point-max) as TO, to limit the scan to the end of the
1805 visible section of the buffer, and pass LINE and COL as TOPOS. */)
1806 (from
, frompos
, to
, topos
, width
, offsets
, window
)
1807 Lisp_Object from
, frompos
, to
, topos
;
1808 Lisp_Object width
, offsets
, window
;
1811 Lisp_Object bufpos
, hpos
, vpos
, prevhpos
;
1812 struct position
*pos
;
1813 int hscroll
, tab_offset
;
1815 CHECK_NUMBER_COERCE_MARKER (from
);
1816 CHECK_CONS (frompos
);
1817 CHECK_NUMBER_CAR (frompos
);
1818 CHECK_NUMBER_CDR (frompos
);
1819 CHECK_NUMBER_COERCE_MARKER (to
);
1823 CHECK_NUMBER_CAR (topos
);
1824 CHECK_NUMBER_CDR (topos
);
1827 CHECK_NUMBER (width
);
1829 if (!NILP (offsets
))
1831 CHECK_CONS (offsets
);
1832 CHECK_NUMBER_CAR (offsets
);
1833 CHECK_NUMBER_CDR (offsets
);
1834 hscroll
= XINT (XCAR (offsets
));
1835 tab_offset
= XINT (XCDR (offsets
));
1838 hscroll
= tab_offset
= 0;
1841 window
= Fselected_window ();
1843 CHECK_LIVE_WINDOW (window
);
1844 w
= XWINDOW (window
);
1846 if (XINT (from
) < BEGV
|| XINT (from
) > ZV
)
1847 args_out_of_range_3 (from
, make_number (BEGV
), make_number (ZV
));
1848 if (XINT (to
) < BEGV
|| XINT (to
) > ZV
)
1849 args_out_of_range_3 (to
, make_number (BEGV
), make_number (ZV
));
1851 pos
= compute_motion (XINT (from
), XINT (XCDR (frompos
)),
1852 XINT (XCAR (frompos
)), 0,
1855 ? window_internal_height (w
)
1856 : XINT (XCDR (topos
))),
1858 ? (window_box_text_cols (w
)
1860 #ifdef HAVE_WINDOW_SYSTEM
1861 FRAME_WINDOW_P (XFRAME (w
->frame
)) ? 0 :
1864 : XINT (XCAR (topos
))),
1865 (NILP (width
) ? -1 : XINT (width
)),
1866 hscroll
, tab_offset
,
1869 XSETFASTINT (bufpos
, pos
->bufpos
);
1870 XSETINT (hpos
, pos
->hpos
);
1871 XSETINT (vpos
, pos
->vpos
);
1872 XSETINT (prevhpos
, pos
->prevhpos
);
1874 return Fcons (bufpos
,
1878 Fcons (pos
->contin
? Qt
: Qnil
, Qnil
)))));
1882 /* Fvertical_motion and vmotion */
1884 struct position val_vmotion
;
1887 vmotion (from
, vtarget
, w
)
1888 register int from
, vtarget
;
1891 int hscroll
= XINT (w
->hscroll
);
1892 struct position pos
;
1893 /* vpos is cumulative vertical position, changed as from is changed */
1894 register int vpos
= 0;
1898 int lmargin
= hscroll
> 0 ? 1 - hscroll
: 0;
1900 = (INTEGERP (current_buffer
->selective_display
)
1901 ? XINT (current_buffer
->selective_display
)
1902 : !NILP (current_buffer
->selective_display
) ? -1 : 0);
1906 /* This is the object we use for fetching character properties. */
1907 Lisp_Object text_prop_object
;
1909 XSETWINDOW (window
, w
);
1911 /* If the window contains this buffer, use it for getting text properties.
1912 Otherwise use the current buffer as arg for doing that. */
1913 if (EQ (w
->buffer
, Fcurrent_buffer ()))
1914 text_prop_object
= window
;
1916 text_prop_object
= Fcurrent_buffer ();
1918 if (vpos
>= vtarget
)
1920 /* To move upward, go a line at a time until
1921 we have gone at least far enough. */
1925 while ((vpos
> vtarget
|| first
) && from
> BEGV
)
1927 Lisp_Object propval
;
1929 prevline
= find_next_newline_no_quit (from
- 1, -1);
1930 while (prevline
> BEGV
1932 && indented_beyond_p (prevline
,
1933 CHAR_TO_BYTE (prevline
),
1934 (double) selective
)) /* iftc */
1935 /* Watch out for newlines with `invisible' property.
1936 When moving upward, check the newline before. */
1937 || (propval
= Fget_char_property (make_number (prevline
- 1),
1940 TEXT_PROP_MEANS_INVISIBLE (propval
))))
1941 prevline
= find_next_newline_no_quit (prevline
- 1, -1);
1942 pos
= *compute_motion (prevline
, 0,
1943 lmargin
+ (prevline
== BEG
? start_hpos
: 0),
1946 /* Don't care for VPOS... */
1947 1 << (BITS_PER_SHORT
- 1),
1949 1 << (BITS_PER_SHORT
- 1),
1951 /* This compensates for start_hpos
1952 so that a tab as first character
1953 still occupies 8 columns. */
1954 (prevline
== BEG
? -start_hpos
: 0),
1961 /* If we made exactly the desired vertical distance,
1962 or if we hit beginning of buffer,
1963 return point found */
1964 if (vpos
>= vtarget
)
1966 val_vmotion
.bufpos
= from
;
1967 val_vmotion
.bytepos
= CHAR_TO_BYTE (from
);
1968 val_vmotion
.vpos
= vpos
;
1969 val_vmotion
.hpos
= lmargin
;
1970 val_vmotion
.contin
= 0;
1971 val_vmotion
.prevhpos
= 0;
1972 val_vmotion
.ovstring_chars_done
= 0;
1973 val_vmotion
.tab_offset
= 0; /* For accumulating tab offset. */
1974 return &val_vmotion
;
1977 /* Otherwise find the correct spot by moving down */
1979 /* Moving downward is simple, but must calculate from beg of line
1980 to determine hpos of starting point */
1981 from_byte
= CHAR_TO_BYTE (from
);
1982 if (from
> BEGV
&& FETCH_BYTE (from_byte
- 1) != '\n')
1984 Lisp_Object propval
;
1986 prevline
= find_next_newline_no_quit (from
, -1);
1987 while (prevline
> BEGV
1989 && indented_beyond_p (prevline
,
1990 CHAR_TO_BYTE (prevline
),
1991 (double) selective
)) /* iftc */
1992 /* Watch out for newlines with `invisible' property.
1993 When moving downward, check the newline after. */
1994 || (propval
= Fget_char_property (make_number (prevline
),
1997 TEXT_PROP_MEANS_INVISIBLE (propval
))))
1998 prevline
= find_next_newline_no_quit (prevline
- 1, -1);
1999 pos
= *compute_motion (prevline
, 0,
2000 lmargin
+ (prevline
== BEG
2004 /* Don't care for VPOS... */
2005 1 << (BITS_PER_SHORT
- 1),
2007 1 << (BITS_PER_SHORT
- 1),
2009 (prevline
== BEG
? -start_hpos
: 0),
2015 pos
.hpos
= lmargin
+ (from
== BEG
? start_hpos
: 0);
2020 return compute_motion (from
, vpos
, pos
.hpos
, did_motion
,
2021 ZV
, vtarget
, - (1 << (BITS_PER_SHORT
- 1)),
2023 pos
.tab_offset
- (from
== BEG
? start_hpos
: 0),
2027 DEFUN ("vertical-motion", Fvertical_motion
, Svertical_motion
, 1, 2, 0,
2028 doc
: /* Move point to start of the screen line LINES lines down.
2029 If LINES is negative, this means moving up.
2031 This function is an ordinary cursor motion function
2032 which calculates the new position based on how text would be displayed.
2033 The new position may be the start of a line,
2034 or just the start of a continuation line.
2035 The function returns number of screen lines moved over;
2036 that usually equals LINES, but may be closer to zero
2037 if beginning or end of buffer was reached.
2039 The optional second argument WINDOW specifies the window to use for
2040 parameters such as width, horizontal scrolling, and so on.
2041 The default is to use the selected window's parameters.
2043 `vertical-motion' always uses the current buffer,
2044 regardless of which buffer is displayed in WINDOW.
2045 This is consistent with other cursor motion functions
2046 and makes it possible to use `vertical-motion' in any buffer,
2047 whether or not it is currently displayed in some window. */)
2049 Lisp_Object lines
, window
;
2054 Lisp_Object old_buffer
;
2055 struct gcpro gcpro1
;
2057 CHECK_NUMBER (lines
);
2058 if (! NILP (window
))
2059 CHECK_WINDOW (window
);
2061 window
= selected_window
;
2062 w
= XWINDOW (window
);
2065 GCPRO1 (old_buffer
);
2066 if (XBUFFER (w
->buffer
) != current_buffer
)
2068 /* Set the window's buffer temporarily to the current buffer. */
2069 old_buffer
= w
->buffer
;
2070 XSETBUFFER (w
->buffer
, current_buffer
);
2075 struct position pos
;
2076 pos
= *vmotion (PT
, XINT (lines
), w
);
2077 SET_PT_BOTH (pos
.bufpos
, pos
.bytepos
);
2083 int it_overshoot_expected
;
2085 SET_TEXT_POS (pt
, PT
, PT_BYTE
);
2086 start_display (&it
, w
, pt
);
2088 /* Scan from the start of the line containing PT. If we don't
2089 do this, we start moving with IT->current_x == 0, while PT is
2090 really at some x > 0. The effect is, in continuation lines, that
2091 we end up with the iterator placed at where it thinks X is 0,
2092 while the end position is really at some X > 0, the same X that
2094 it_start
= IT_CHARPOS (it
);
2096 /* We expect the call to move_it_to, further down, to overshoot
2097 if the starting point is on an image, stretch glyph,
2098 composition, or Lisp string. We won't need to backtrack in
2099 this situation, except for one corner case: when the Lisp
2100 string contains a newline. */
2101 if (it
.method
== GET_FROM_STRING
)
2103 const char *s
= SDATA (it
.string
);
2104 const char *e
= s
+ SBYTES (it
.string
);
2106 while (s
< e
&& *s
!= '\n')
2109 /* If there is no newline in the string, we need to check
2110 whether there is a newline immediately after the string
2111 in move_it_to below. This may happen if there is an
2112 overlay with an after-string just before the newline. */
2113 it_overshoot_expected
= (s
== e
) ? -1 : 0;
2116 it_overshoot_expected
= (it
.method
== GET_FROM_IMAGE
2117 || it
.method
== GET_FROM_STRETCH
2118 || it
.method
== GET_FROM_COMPOSITION
);
2120 reseat_at_previous_visible_line_start (&it
);
2121 it
.current_x
= it
.hpos
= 0;
2122 /* Temporarily disable selective display so we don't move too far */
2123 oselective
= it
.selective
;
2125 move_it_to (&it
, PT
, -1, -1, -1, MOVE_TO_POS
);
2126 it
.selective
= oselective
;
2128 /* Move back if we got too far. This may happen if
2129 truncate-lines is on and PT is beyond right margin.
2130 Don't go back if the overshoot is expected (see above). */
2131 if (IT_CHARPOS (it
) > it_start
&& XINT (lines
) > 0
2132 && (!it_overshoot_expected
2133 || (it_overshoot_expected
< 0
2134 && it
.method
== GET_FROM_BUFFER
2136 move_it_by_lines (&it
, -1, 0);
2139 /* Do this even if LINES is 0, so that we move back
2140 to the beginning of the current line as we ought. */
2141 if (XINT (lines
) >= 0 || IT_CHARPOS (it
) > 0)
2142 move_it_by_lines (&it
, XINT (lines
), 0);
2144 SET_PT_BOTH (IT_CHARPOS (it
), IT_BYTEPOS (it
));
2147 if (BUFFERP (old_buffer
))
2148 w
->buffer
= old_buffer
;
2150 RETURN_UNGCPRO (make_number (it
.vpos
));
2155 /* File's initialization. */
2160 DEFVAR_BOOL ("indent-tabs-mode", &indent_tabs_mode
,
2161 doc
: /* *Indentation can insert tabs if this is non-nil.
2162 Setting this variable automatically makes it local to the current buffer. */);
2163 indent_tabs_mode
= 1;
2165 defsubr (&Scurrent_indentation
);
2166 defsubr (&Sindent_to
);
2167 defsubr (&Scurrent_column
);
2168 defsubr (&Smove_to_column
);
2169 defsubr (&Svertical_motion
);
2170 defsubr (&Scompute_motion
);
2173 /* arch-tag: 9adfea44-71f7-4988-8ee3-96da15c502cc
2174 (do not change this comment) */