1 /* Indentation functions.
2 Copyright (C) 1985, 1986, 1987, 1988, 1993, 1994, 1995, 1998, 2000, 2001,
3 2002, 2003, 2004, 2005, 2006 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 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 The column of a character is calculated by adding together the widths
915 as displayed of the previous characters in the line.
916 This function ignores line-continuation;
917 there is no upper limit on the column number a character can have
918 and horizontal scrolling has no effect.
920 If specified column is within a character, point goes after that character.
921 If it's past end of line, point goes to end of line.
923 A non-nil second (optional) argument FORCE means,
924 if COLUMN is in the middle of a tab character, change it to spaces.
925 In addition, if FORCE is t, and the line is too short
926 to reach column COLUMN, add spaces/tabs to get there.
928 The return value is the current column. */)
930 Lisp_Object column
, force
;
933 register int col
= current_column ();
936 register int tab_width
= XINT (current_buffer
->tab_width
);
937 register int ctl_arrow
= !NILP (current_buffer
->ctl_arrow
);
938 register struct Lisp_Char_Table
*dp
= buffer_display_table ();
939 register int multibyte
= !NILP (current_buffer
->enable_multibyte_characters
);
944 int next_boundary
, pos_byte
;
946 if (tab_width
<= 0 || tab_width
> 1000) tab_width
= 8;
947 CHECK_NATNUM (column
);
948 goal
= XINT (column
);
955 /* If we're starting past the desired column,
956 back up to beginning of line and scan from there. */
960 pos
= current_column_bol_cache
;
961 pos_byte
= CHAR_TO_BYTE (pos
);
967 while (pos
== next_boundary
)
970 pos
= skip_invisible (pos
, &next_boundary
, end
, Qnil
);
972 pos_byte
= CHAR_TO_BYTE (pos
);
977 /* Test reaching the goal column. We do this after skipping
978 invisible characters, so that we put point before the
979 character on which the cursor will appear. */
983 /* Check composition sequence. */
985 int len
, len_byte
, width
;
987 if (check_composition (pos
, pos_byte
, Z
, &len
, &len_byte
, &width
))
990 pos_byte
+= len_byte
;
996 c
= FETCH_BYTE (pos_byte
);
998 /* See if there is a display table and it relates
999 to this character. */
1002 && ! (multibyte
&& BASE_LEADING_CODE_P (c
))
1003 && VECTORP (DISP_CHAR_VECTOR (dp
, c
)))
1005 Lisp_Object charvec
;
1008 /* This character is displayed using a vector of glyphs.
1009 Update the position based on those glyphs. */
1011 charvec
= DISP_CHAR_VECTOR (dp
, c
);
1012 n
= ASIZE (charvec
);
1014 for (i
= 0; i
< n
; i
++)
1016 /* This should be handled the same as
1017 next_element_from_display_vector does it. */
1020 entry
= AREF (charvec
, i
);
1022 if (INTEGERP (entry
)
1023 && GLYPH_CHAR_VALID_P (XFASTINT (entry
)))
1024 c
= FAST_GLYPH_CHAR (XFASTINT (entry
));
1030 if (c
== '\r' && EQ (current_buffer
->selective_display
, Qt
))
1036 col
= col
/ tab_width
* tab_width
;
1044 /* The display table doesn't affect this character;
1045 it displays as itself. */
1049 if (c
== '\r' && EQ (current_buffer
->selective_display
, Qt
))
1055 col
= col
/ tab_width
* tab_width
;
1057 else if (ctl_arrow
&& (c
< 040 || c
== 0177))
1059 else if (c
< 040 || c
== 0177)
1063 else if (multibyte
&& BASE_LEADING_CODE_P (c
))
1065 /* Start of multi-byte form. */
1067 int bytes
, width
, wide_column
;
1069 ptr
= BYTE_POS_ADDR (pos_byte
);
1070 MULTIBYTE_BYTES_WIDTH (ptr
, dp
);
1071 pos_byte
+= bytes
- 1;
1083 SET_PT_BOTH (pos
, pos_byte
);
1085 /* If a tab char made us overshoot, change it to spaces
1086 and scan through it again. */
1087 if (!NILP (force
) && col
> goal
&& c
== '\t' && prev_col
< goal
)
1089 int goal_pt
, goal_pt_byte
;
1091 /* Insert spaces in front of the tab to reach GOAL. Do this
1092 first so that a marker at the end of the tab gets
1094 SET_PT_BOTH (PT
- 1, PT_BYTE
- 1);
1095 Finsert_char (make_number (' '), make_number (goal
- prev_col
), Qt
);
1097 /* Now delete the tab, and indent to COL. */
1098 del_range (PT
, PT
+ 1);
1100 goal_pt_byte
= PT_BYTE
;
1101 Findent_to (make_number (col
), Qnil
);
1102 SET_PT_BOTH (goal_pt
, goal_pt_byte
);
1104 /* Set the last_known... vars consistently. */
1108 /* If line ends prematurely, add space to the end. */
1109 if (col
< goal
&& EQ (force
, Qt
))
1110 Findent_to (make_number (col
= goal
), Qnil
);
1112 last_known_column
= col
;
1113 last_known_column_point
= PT
;
1114 last_known_column_modified
= MODIFF
;
1116 XSETFASTINT (val
, col
);
1120 /* compute_motion: compute buffer posn given screen posn and vice versa */
1122 struct position val_compute_motion
;
1124 /* Scan the current buffer forward from offset FROM, pretending that
1125 this is at line FROMVPOS, column FROMHPOS, until reaching buffer
1126 offset TO or line TOVPOS, column TOHPOS (whichever comes first),
1127 and return the ending buffer position and screen location. If we
1128 can't hit the requested column exactly (because of a tab or other
1129 multi-column character), overshoot.
1131 DID_MOTION is 1 if FROMHPOS has already accounted for overlay strings
1132 at FROM. This is the case if FROMVPOS and FROMVPOS came from an
1133 earlier call to compute_motion. The other common case is that FROMHPOS
1134 is zero and FROM is a position that "belongs" at column zero, but might
1135 be shifted by overlay strings; in this case DID_MOTION should be 0.
1137 WIDTH is the number of columns available to display text;
1138 compute_motion uses this to handle continuation lines and such.
1139 If WIDTH is -1, use width of window's text area adjusted for
1140 continuation glyph when needed.
1142 HSCROLL is the number of columns not being displayed at the left
1143 margin; this is usually taken from a window's hscroll member.
1144 TAB_OFFSET is the number of columns of the first tab that aren't
1145 being displayed, perhaps because of a continuation line or
1148 compute_motion returns a pointer to a struct position. The bufpos
1149 member gives the buffer position at the end of the scan, and hpos
1150 and vpos give its cartesian location. prevhpos is the column at
1151 which the character before bufpos started, and contin is non-zero
1152 if we reached the current line by continuing the previous.
1154 Note that FROMHPOS and TOHPOS should be expressed in real screen
1155 columns, taking HSCROLL and the truncation glyph at the left margin
1156 into account. That is, beginning-of-line moves you to the hpos
1157 -HSCROLL + (HSCROLL > 0).
1159 For example, to find the buffer position of column COL of line LINE
1160 of a certain window, pass the window's starting location as FROM
1161 and the window's upper-left coordinates as FROMVPOS and FROMHPOS.
1162 Pass the buffer's ZV as TO, to limit the scan to the end of the
1163 visible section of the buffer, and pass LINE and COL as TOVPOS and
1166 When displaying in window w, a typical formula for WIDTH is:
1169 - (has_vertical_scroll_bars
1170 ? WINDOW_CONFIG_SCROLL_BAR_COLS (window)
1171 : (window_width + window_left != frame_cols))
1174 window_width is XFASTINT (w->total_cols),
1175 window_left is XFASTINT (w->left_col),
1176 has_vertical_scroll_bars is
1177 WINDOW_HAS_VERTICAL_SCROLL_BAR (window)
1178 and frame_cols = FRAME_COLS (XFRAME (window->frame))
1180 Or you can let window_box_text_cols do this all for you, and write:
1181 window_box_text_cols (w) - 1
1183 The `-1' accounts for the continuation-line backslashes; the rest
1184 accounts for window borders if the window is split horizontally, and
1185 the scroll bars if they are turned on. */
1188 compute_motion (from
, fromvpos
, fromhpos
, did_motion
, to
, tovpos
, tohpos
, width
, hscroll
, tab_offset
, win
)
1189 int from
, fromvpos
, fromhpos
, to
, tovpos
, tohpos
;
1192 int hscroll
, tab_offset
;
1195 register int hpos
= fromhpos
;
1196 register int vpos
= fromvpos
;
1201 register int tab_width
= XFASTINT (current_buffer
->tab_width
);
1202 register int ctl_arrow
= !NILP (current_buffer
->ctl_arrow
);
1203 register struct Lisp_Char_Table
*dp
= window_display_table (win
);
1205 = (INTEGERP (current_buffer
->selective_display
)
1206 ? XINT (current_buffer
->selective_display
)
1207 : !NILP (current_buffer
->selective_display
) ? -1 : 0);
1209 = (selective
&& dp
&& VECTORP (DISP_INVIS_VECTOR (dp
))
1210 ? XVECTOR (DISP_INVIS_VECTOR (dp
))->size
: 0);
1211 /* The next location where the `invisible' property changes, or an
1212 overlay starts or ends. */
1213 int next_boundary
= from
;
1215 /* For computing runs of characters with similar widths.
1216 Invariant: width_run_width is zero, or all the characters
1217 from width_run_start to width_run_end have a fixed width of
1219 int width_run_start
= from
;
1220 int width_run_end
= from
;
1221 int width_run_width
= 0;
1222 Lisp_Object
*width_table
;
1225 /* The next buffer pos where we should consult the width run cache. */
1226 int next_width_run
= from
;
1229 int multibyte
= !NILP (current_buffer
->enable_multibyte_characters
);
1230 /* If previous char scanned was a wide character,
1231 this is the column where it ended. Otherwise, this is 0. */
1232 int wide_column_end_hpos
= 0;
1233 int prev_pos
; /* Previous buffer position. */
1234 int prev_pos_byte
; /* Previous buffer position. */
1237 int contin_hpos
; /* HPOS of last column of continued line. */
1238 int prev_tab_offset
; /* Previous tab offset. */
1239 int continuation_glyph_width
;
1241 XSETBUFFER (buffer
, current_buffer
);
1242 XSETWINDOW (window
, win
);
1244 width_run_cache_on_off ();
1245 if (dp
== buffer_display_table ())
1246 width_table
= (VECTORP (current_buffer
->width_table
)
1247 ? XVECTOR (current_buffer
->width_table
)->contents
1250 /* If the window has its own display table, we can't use the width
1251 run cache, because that's based on the buffer's display table. */
1254 if (tab_width
<= 0 || tab_width
> 1000)
1257 /* Negative width means use all available text columns. */
1260 width
= window_box_text_cols (win
);
1261 /* We must make room for continuation marks if we don't have fringes. */
1262 #ifdef HAVE_WINDOW_SYSTEM
1263 if (!FRAME_WINDOW_P (XFRAME (win
->frame
)))
1268 continuation_glyph_width
= 1;
1269 #ifdef HAVE_WINDOW_SYSTEM
1270 if (FRAME_WINDOW_P (XFRAME (win
->frame
)))
1271 continuation_glyph_width
= 0; /* In the fringe. */
1277 pos
= prev_pos
= from
;
1278 pos_byte
= prev_pos_byte
= CHAR_TO_BYTE (from
);
1280 prev_tab_offset
= tab_offset
;
1283 while (pos
== next_boundary
)
1288 /* Don't skip invisible if we are already at the margin. */
1289 if (vpos
> tovpos
|| (vpos
== tovpos
&& hpos
>= tohpos
))
1291 if (contin_hpos
&& prev_hpos
== 0
1293 && (contin_hpos
== width
|| wide_column_end_hpos
> width
))
1294 { /* Line breaks because we can't put the character at the
1295 previous line any more. It is not the multi-column
1296 character continued in middle. Go back to previous
1297 buffer position, screen position, and set tab offset
1298 to previous value. It's the beginning of the
1301 pos_byte
= prev_pos_byte
;
1304 tab_offset
= prev_tab_offset
;
1309 /* If the caller says that the screen position came from an earlier
1310 call to compute_motion, then we've already accounted for the
1311 overlay strings at point. This is only true the first time
1312 through, so clear the flag after testing it. */
1314 /* We need to skip past the overlay strings. Currently those
1315 strings must not contain TAB;
1316 if we want to relax that restriction, something will have
1317 to be changed here. */
1319 unsigned char *ovstr
;
1320 int ovlen
= overlay_strings (pos
, win
, &ovstr
);
1321 hpos
+= ((multibyte
&& ovlen
> 0)
1322 ? strwidth (ovstr
, ovlen
) : ovlen
);
1329 /* Advance POS past invisible characters
1330 (but not necessarily all that there are here),
1331 and store in next_boundary the next position where
1332 we need to call skip_invisible. */
1333 newpos
= skip_invisible (pos
, &next_boundary
, to
, window
);
1337 pos
= min (to
, newpos
);
1338 pos_byte
= CHAR_TO_BYTE (pos
);
1342 if (newpos
!= pos_here
)
1345 pos_byte
= CHAR_TO_BYTE (pos
);
1349 /* Handle right margin. */
1350 /* Note on a wide-column character.
1352 Characters are classified into the following three categories
1353 according to the width (columns occupied on screen).
1355 (1) single-column character: ex. `a'
1356 (2) multi-column character: ex. `^A', TAB, `\033'
1357 (3) wide-column character: ex. Japanese character, Chinese character
1358 (In the following example, `W_' stands for them.)
1360 Multi-column characters can be divided around the right margin,
1361 but wide-column characters cannot.
1365 (*) The cursor is placed on the next character after the point.
1369 j ^---- next after the point
1370 ^--- next char. after the point.
1372 In case of sigle-column character
1376 033 ^---- next after the point, next char. after the point.
1378 In case of multi-column character
1382 W_ ^---- next after the point
1383 ^---- next char. after the point.
1385 In case of wide-column character
1387 The problem here is continuation at a wide-column character.
1388 In this case, the line may shorter less than WIDTH.
1389 And we find the continuation AFTER it occurs.
1396 || (truncate_partial_width_windows
1397 && ((width
+ continuation_glyph_width
)
1398 < FRAME_COLS (XFRAME (WINDOW_FRAME (win
)))))
1399 || !NILP (current_buffer
->truncate_lines
))
1401 /* Truncating: skip to newline, unless we are already past
1402 TO (we need to go back below). */
1405 pos
= find_before_next_newline (pos
, to
, 1);
1406 pos_byte
= CHAR_TO_BYTE (pos
);
1408 /* If we just skipped next_boundary,
1409 loop around in the main while
1411 if (pos
>= next_boundary
)
1412 next_boundary
= pos
+ 1;
1415 prev_tab_offset
= tab_offset
;
1421 /* Remember the previous value. */
1422 prev_tab_offset
= tab_offset
;
1424 if (wide_column_end_hpos
> width
)
1427 tab_offset
+= prev_hpos
;
1431 tab_offset
+= width
;
1435 contin_hpos
= prev_hpos
;
1441 /* Stop if past the target buffer position or screen position. */
1444 /* Go back to the previous position. */
1446 pos_byte
= prev_pos_byte
;
1449 tab_offset
= prev_tab_offset
;
1451 /* NOTE on contin_hpos, hpos, and prev_hpos.
1455 W_ ^---- contin_hpos
1461 if (contin_hpos
&& prev_hpos
== 0
1462 && contin_hpos
< width
&& !wide_column_end_hpos
)
1464 /* Line breaking occurs in the middle of multi-column
1465 character. Go back to previous line. */
1472 if (vpos
> tovpos
|| (vpos
== tovpos
&& hpos
>= tohpos
))
1474 if (contin_hpos
&& prev_hpos
== 0
1476 && (contin_hpos
== width
|| wide_column_end_hpos
> width
))
1477 { /* Line breaks because we can't put the character at the
1478 previous line any more. It is not the multi-column
1479 character continued in middle. Go back to previous
1480 buffer position, screen position, and set tab offset
1481 to previous value. It's the beginning of the
1484 pos_byte
= prev_pos_byte
;
1487 tab_offset
= prev_tab_offset
;
1491 if (pos
== ZV
) /* We cannot go beyond ZV. Stop here. */
1497 prev_pos_byte
= pos_byte
;
1498 wide_column_end_hpos
= 0;
1500 /* Consult the width run cache to see if we can avoid inspecting
1501 the text character-by-character. */
1502 if (current_buffer
->width_run_cache
&& pos
>= next_width_run
)
1506 = region_cache_forward (current_buffer
,
1507 current_buffer
->width_run_cache
,
1510 /* A width of zero means the character's width varies (like
1511 a tab), is meaningless (like a newline), or we just don't
1512 want to skip over it for some other reason. */
1513 if (common_width
!= 0)
1517 /* Don't go past the final buffer posn the user
1522 run_end_hpos
= hpos
+ (run_end
- pos
) * common_width
;
1524 /* Don't go past the final horizontal position the user
1526 if (vpos
== tovpos
&& run_end_hpos
> tohpos
)
1528 run_end
= pos
+ (tohpos
- hpos
) / common_width
;
1529 run_end_hpos
= hpos
+ (run_end
- pos
) * common_width
;
1532 /* Don't go past the margin. */
1533 if (run_end_hpos
>= width
)
1535 run_end
= pos
+ (width
- hpos
) / common_width
;
1536 run_end_hpos
= hpos
+ (run_end
- pos
) * common_width
;
1539 hpos
= run_end_hpos
;
1541 prev_hpos
= hpos
- common_width
;
1545 pos_byte
= CHAR_TO_BYTE (pos
);
1549 next_width_run
= run_end
+ 1;
1552 /* We have to scan the text character-by-character. */
1556 Lisp_Object charvec
;
1558 c
= FETCH_BYTE (pos_byte
);
1560 /* Check composition sequence. */
1562 int len
, len_byte
, width
;
1564 if (check_composition (pos
, pos_byte
, to
, &len
, &len_byte
, &width
))
1567 pos_byte
+= len_byte
;
1575 /* Perhaps add some info to the width_run_cache. */
1576 if (current_buffer
->width_run_cache
)
1578 /* Is this character part of the current run? If so, extend
1580 if (pos
- 1 == width_run_end
1581 && XFASTINT (width_table
[c
]) == width_run_width
)
1582 width_run_end
= pos
;
1584 /* The previous run is over, since this is a character at a
1585 different position, or a different width. */
1588 /* Have we accumulated a run to put in the cache?
1589 (Currently, we only cache runs of width == 1). */
1590 if (width_run_start
< width_run_end
1591 && width_run_width
== 1)
1592 know_region_cache (current_buffer
,
1593 current_buffer
->width_run_cache
,
1594 width_run_start
, width_run_end
);
1596 /* Start recording a new width run. */
1597 width_run_width
= XFASTINT (width_table
[c
]);
1598 width_run_start
= pos
- 1;
1599 width_run_end
= pos
;
1604 && ! (multibyte
&& BASE_LEADING_CODE_P (c
))
1605 && VECTORP (DISP_CHAR_VECTOR (dp
, c
)))
1607 charvec
= DISP_CHAR_VECTOR (dp
, c
);
1608 n
= ASIZE (charvec
);
1616 for (i
= n
- 1; i
>= 0; --i
)
1618 if (VECTORP (charvec
))
1620 /* This should be handled the same as
1621 next_element_from_display_vector does it. */
1622 Lisp_Object entry
= AREF (charvec
, i
);
1624 if (INTEGERP (entry
)
1625 && GLYPH_CHAR_VALID_P (XFASTINT (entry
)))
1626 c
= FAST_GLYPH_CHAR (XFASTINT (entry
));
1631 if (c
>= 040 && c
< 0177)
1635 int tem
= ((hpos
+ tab_offset
+ hscroll
- (hscroll
> 0))
1639 hpos
+= tab_width
- tem
;
1644 && indented_beyond_p (pos
, pos_byte
,
1645 (double) selective
)) /* iftc */
1647 /* If (pos == to), we don't have to take care of
1648 selective display. */
1651 /* Skip any number of invisible lines all at once */
1654 pos
= find_before_next_newline (pos
, to
, 1);
1657 pos_byte
= CHAR_TO_BYTE (pos
);
1660 && indented_beyond_p (pos
, pos_byte
,
1661 (double) selective
)); /* iftc */
1662 /* Allow for the " ..." that is displayed for them. */
1665 hpos
+= selective_rlen
;
1669 DEC_BOTH (pos
, pos_byte
);
1670 /* We have skipped the invis text, but not the
1676 /* A visible line. */
1680 /* Count the truncation glyph on column 0 */
1682 hpos
+= continuation_glyph_width
;
1687 else if (c
== CR
&& selective
< 0)
1689 /* In selective display mode,
1690 everything from a ^M to the end of the line is invisible.
1691 Stop *before* the real newline. */
1694 pos
= find_before_next_newline (pos
, to
, 1);
1695 pos_byte
= CHAR_TO_BYTE (pos
);
1697 /* If we just skipped next_boundary,
1698 loop around in the main while
1700 if (pos
> next_boundary
)
1701 next_boundary
= pos
;
1702 /* Allow for the " ..." that is displayed for them. */
1705 hpos
+= selective_rlen
;
1710 else if (multibyte
&& BASE_LEADING_CODE_P (c
))
1712 /* Start of multi-byte form. */
1714 int bytes
, width
, wide_column
;
1716 pos_byte
--; /* rewind POS_BYTE */
1717 ptr
= BYTE_POS_ADDR (pos_byte
);
1718 MULTIBYTE_BYTES_WIDTH (ptr
, dp
);
1721 wide_column_end_hpos
= hpos
+ wide_column
;
1724 else if (VECTORP (charvec
))
1727 hpos
+= (ctl_arrow
&& c
< 0200) ? 2 : 4;
1734 /* Remember any final width run in the cache. */
1735 if (current_buffer
->width_run_cache
1736 && width_run_width
== 1
1737 && width_run_start
< width_run_end
)
1738 know_region_cache (current_buffer
, current_buffer
->width_run_cache
,
1739 width_run_start
, width_run_end
);
1741 val_compute_motion
.bufpos
= pos
;
1742 val_compute_motion
.bytepos
= pos_byte
;
1743 val_compute_motion
.hpos
= hpos
;
1744 val_compute_motion
.vpos
= vpos
;
1745 if (contin_hpos
&& prev_hpos
== 0)
1746 val_compute_motion
.prevhpos
= contin_hpos
;
1748 val_compute_motion
.prevhpos
= prev_hpos
;
1749 /* We alalways handle all of them here; none of them remain to do. */
1750 val_compute_motion
.ovstring_chars_done
= 0;
1752 /* Nonzero if have just continued a line */
1753 val_compute_motion
.contin
= (contin_hpos
&& prev_hpos
== 0);
1756 return &val_compute_motion
;
1760 DEFUN ("compute-motion", Fcompute_motion
, Scompute_motion
, 7, 7, 0,
1761 doc
: /* Scan through the current buffer, calculating screen position.
1762 Scan the current buffer forward from offset FROM,
1763 assuming it is at position FROMPOS--a cons of the form (HPOS . VPOS)--
1764 to position TO or position TOPOS--another cons of the form (HPOS . VPOS)--
1765 and return the ending buffer position and screen location.
1767 If TOPOS is nil, the actual width and height of the window's
1770 There are three additional arguments:
1772 WIDTH is the number of columns available to display text;
1773 this affects handling of continuation lines. A value of nil
1774 corresponds to the actual number of available text columns.
1776 OFFSETS is either nil or a cons cell (HSCROLL . TAB-OFFSET).
1777 HSCROLL is the number of columns not being displayed at the left
1778 margin; this is usually taken from a window's hscroll member.
1779 TAB-OFFSET is the number of columns of the first tab that aren't
1780 being displayed, perhaps because the line was continued within it.
1781 If OFFSETS is nil, HSCROLL and TAB-OFFSET are assumed to be zero.
1783 WINDOW is the window to operate on. It is used to choose the display table;
1784 if it is showing the current buffer, it is used also for
1785 deciding which overlay properties apply.
1786 Note that `compute-motion' always operates on the current buffer.
1788 The value is a list of five elements:
1789 (POS HPOS VPOS PREVHPOS CONTIN)
1790 POS is the buffer position where the scan stopped.
1791 VPOS is the vertical position where the scan stopped.
1792 HPOS is the horizontal position where the scan stopped.
1794 PREVHPOS is the horizontal position one character back from POS.
1795 CONTIN is t if a line was continued after (or within) the previous character.
1797 For example, to find the buffer position of column COL of line LINE
1798 of a certain window, pass the window's starting location as FROM
1799 and the window's upper-left coordinates as FROMPOS.
1800 Pass the buffer's (point-max) as TO, to limit the scan to the end of the
1801 visible section of the buffer, and pass LINE and COL as TOPOS. */)
1802 (from
, frompos
, to
, topos
, width
, offsets
, window
)
1803 Lisp_Object from
, frompos
, to
, topos
;
1804 Lisp_Object width
, offsets
, window
;
1807 Lisp_Object bufpos
, hpos
, vpos
, prevhpos
;
1808 struct position
*pos
;
1809 int hscroll
, tab_offset
;
1811 CHECK_NUMBER_COERCE_MARKER (from
);
1812 CHECK_CONS (frompos
);
1813 CHECK_NUMBER_CAR (frompos
);
1814 CHECK_NUMBER_CDR (frompos
);
1815 CHECK_NUMBER_COERCE_MARKER (to
);
1819 CHECK_NUMBER_CAR (topos
);
1820 CHECK_NUMBER_CDR (topos
);
1823 CHECK_NUMBER (width
);
1825 if (!NILP (offsets
))
1827 CHECK_CONS (offsets
);
1828 CHECK_NUMBER_CAR (offsets
);
1829 CHECK_NUMBER_CDR (offsets
);
1830 hscroll
= XINT (XCAR (offsets
));
1831 tab_offset
= XINT (XCDR (offsets
));
1834 hscroll
= tab_offset
= 0;
1837 window
= Fselected_window ();
1839 CHECK_LIVE_WINDOW (window
);
1840 w
= XWINDOW (window
);
1842 if (XINT (from
) < BEGV
|| XINT (from
) > ZV
)
1843 args_out_of_range_3 (from
, make_number (BEGV
), make_number (ZV
));
1844 if (XINT (to
) < BEGV
|| XINT (to
) > ZV
)
1845 args_out_of_range_3 (to
, make_number (BEGV
), make_number (ZV
));
1847 pos
= compute_motion (XINT (from
), XINT (XCDR (frompos
)),
1848 XINT (XCAR (frompos
)), 0,
1851 ? window_internal_height (w
)
1852 : XINT (XCDR (topos
))),
1854 ? (window_box_text_cols (w
)
1856 #ifdef HAVE_WINDOW_SYSTEM
1857 FRAME_WINDOW_P (XFRAME (w
->frame
)) ? 0 :
1860 : XINT (XCAR (topos
))),
1861 (NILP (width
) ? -1 : XINT (width
)),
1862 hscroll
, tab_offset
,
1865 XSETFASTINT (bufpos
, pos
->bufpos
);
1866 XSETINT (hpos
, pos
->hpos
);
1867 XSETINT (vpos
, pos
->vpos
);
1868 XSETINT (prevhpos
, pos
->prevhpos
);
1870 return Fcons (bufpos
,
1874 Fcons (pos
->contin
? Qt
: Qnil
, Qnil
)))));
1878 /* Fvertical_motion and vmotion */
1880 struct position val_vmotion
;
1883 vmotion (from
, vtarget
, w
)
1884 register int from
, vtarget
;
1887 int hscroll
= XINT (w
->hscroll
);
1888 struct position pos
;
1889 /* vpos is cumulative vertical position, changed as from is changed */
1890 register int vpos
= 0;
1894 int lmargin
= hscroll
> 0 ? 1 - hscroll
: 0;
1896 = (INTEGERP (current_buffer
->selective_display
)
1897 ? XINT (current_buffer
->selective_display
)
1898 : !NILP (current_buffer
->selective_display
) ? -1 : 0);
1902 /* This is the object we use for fetching character properties. */
1903 Lisp_Object text_prop_object
;
1905 XSETWINDOW (window
, w
);
1907 /* If the window contains this buffer, use it for getting text properties.
1908 Otherwise use the current buffer as arg for doing that. */
1909 if (EQ (w
->buffer
, Fcurrent_buffer ()))
1910 text_prop_object
= window
;
1912 text_prop_object
= Fcurrent_buffer ();
1914 if (vpos
>= vtarget
)
1916 /* To move upward, go a line at a time until
1917 we have gone at least far enough. */
1921 while ((vpos
> vtarget
|| first
) && from
> BEGV
)
1923 Lisp_Object propval
;
1925 prevline
= find_next_newline_no_quit (from
- 1, -1);
1926 while (prevline
> BEGV
1928 && indented_beyond_p (prevline
,
1929 CHAR_TO_BYTE (prevline
),
1930 (double) selective
)) /* iftc */
1931 /* Watch out for newlines with `invisible' property.
1932 When moving upward, check the newline before. */
1933 || (propval
= Fget_char_property (make_number (prevline
- 1),
1936 TEXT_PROP_MEANS_INVISIBLE (propval
))))
1937 prevline
= find_next_newline_no_quit (prevline
- 1, -1);
1938 pos
= *compute_motion (prevline
, 0,
1939 lmargin
+ (prevline
== BEG
? start_hpos
: 0),
1942 /* Don't care for VPOS... */
1943 1 << (BITS_PER_SHORT
- 1),
1945 1 << (BITS_PER_SHORT
- 1),
1947 /* This compensates for start_hpos
1948 so that a tab as first character
1949 still occupies 8 columns. */
1950 (prevline
== BEG
? -start_hpos
: 0),
1957 /* If we made exactly the desired vertical distance,
1958 or if we hit beginning of buffer,
1959 return point found */
1960 if (vpos
>= vtarget
)
1962 val_vmotion
.bufpos
= from
;
1963 val_vmotion
.bytepos
= CHAR_TO_BYTE (from
);
1964 val_vmotion
.vpos
= vpos
;
1965 val_vmotion
.hpos
= lmargin
;
1966 val_vmotion
.contin
= 0;
1967 val_vmotion
.prevhpos
= 0;
1968 val_vmotion
.ovstring_chars_done
= 0;
1969 val_vmotion
.tab_offset
= 0; /* For accumulating tab offset. */
1970 return &val_vmotion
;
1973 /* Otherwise find the correct spot by moving down */
1975 /* Moving downward is simple, but must calculate from beg of line
1976 to determine hpos of starting point */
1977 from_byte
= CHAR_TO_BYTE (from
);
1978 if (from
> BEGV
&& FETCH_BYTE (from_byte
- 1) != '\n')
1980 Lisp_Object propval
;
1982 prevline
= find_next_newline_no_quit (from
, -1);
1983 while (prevline
> BEGV
1985 && indented_beyond_p (prevline
,
1986 CHAR_TO_BYTE (prevline
),
1987 (double) selective
)) /* iftc */
1988 /* Watch out for newlines with `invisible' property.
1989 When moving downward, check the newline after. */
1990 || (propval
= Fget_char_property (make_number (prevline
),
1993 TEXT_PROP_MEANS_INVISIBLE (propval
))))
1994 prevline
= find_next_newline_no_quit (prevline
- 1, -1);
1995 pos
= *compute_motion (prevline
, 0,
1996 lmargin
+ (prevline
== BEG
2000 /* Don't care for VPOS... */
2001 1 << (BITS_PER_SHORT
- 1),
2003 1 << (BITS_PER_SHORT
- 1),
2005 (prevline
== BEG
? -start_hpos
: 0),
2011 pos
.hpos
= lmargin
+ (from
== BEG
? start_hpos
: 0);
2016 return compute_motion (from
, vpos
, pos
.hpos
, did_motion
,
2017 ZV
, vtarget
, - (1 << (BITS_PER_SHORT
- 1)),
2019 pos
.tab_offset
- (from
== BEG
? start_hpos
: 0),
2023 DEFUN ("vertical-motion", Fvertical_motion
, Svertical_motion
, 1, 2, 0,
2024 doc
: /* Move point to start of the screen line LINES lines down.
2025 If LINES is negative, this means moving up.
2027 This function is an ordinary cursor motion function
2028 which calculates the new position based on how text would be displayed.
2029 The new position may be the start of a line,
2030 or just the start of a continuation line.
2031 The function returns number of screen lines moved over;
2032 that usually equals LINES, but may be closer to zero
2033 if beginning or end of buffer was reached.
2035 The optional second argument WINDOW specifies the window to use for
2036 parameters such as width, horizontal scrolling, and so on.
2037 The default is to use the selected window's parameters.
2039 `vertical-motion' always uses the current buffer,
2040 regardless of which buffer is displayed in WINDOW.
2041 This is consistent with other cursor motion functions
2042 and makes it possible to use `vertical-motion' in any buffer,
2043 whether or not it is currently displayed in some window. */)
2045 Lisp_Object lines
, window
;
2050 Lisp_Object old_buffer
;
2051 struct gcpro gcpro1
;
2053 CHECK_NUMBER (lines
);
2054 if (! NILP (window
))
2055 CHECK_WINDOW (window
);
2057 window
= selected_window
;
2058 w
= XWINDOW (window
);
2061 GCPRO1 (old_buffer
);
2062 if (XBUFFER (w
->buffer
) != current_buffer
)
2064 /* Set the window's buffer temporarily to the current buffer. */
2065 old_buffer
= w
->buffer
;
2066 XSETBUFFER (w
->buffer
, current_buffer
);
2071 struct position pos
;
2072 pos
= *vmotion (PT
, XINT (lines
), w
);
2073 SET_PT_BOTH (pos
.bufpos
, pos
.bytepos
);
2079 int it_overshoot_expected
;
2081 SET_TEXT_POS (pt
, PT
, PT_BYTE
);
2082 start_display (&it
, w
, pt
);
2084 /* Scan from the start of the line containing PT. If we don't
2085 do this, we start moving with IT->current_x == 0, while PT is
2086 really at some x > 0. The effect is, in continuation lines, that
2087 we end up with the iterator placed at where it thinks X is 0,
2088 while the end position is really at some X > 0, the same X that
2090 it_start
= IT_CHARPOS (it
);
2092 /* We expect the call to move_it_to, further down, to overshoot
2093 if the starting point is on an image, stretch glyph,
2094 composition, or Lisp string. We won't need to backtrack in
2095 this situation, except for one corner case: when the Lisp
2096 string contains a newline. */
2097 if (it
.method
== GET_FROM_STRING
)
2099 const char *s
= SDATA (it
.string
);
2100 const char *e
= s
+ SBYTES (it
.string
);
2102 while (s
< e
&& *s
!= '\n')
2105 /* If there is no newline in the string, we need to check
2106 whether there is a newline immediately after the string
2107 in move_it_to below. This may happen if there is an
2108 overlay with an after-string just before the newline. */
2109 it_overshoot_expected
= (s
== e
) ? -1 : 0;
2112 it_overshoot_expected
= (it
.method
== GET_FROM_IMAGE
2113 || it
.method
== GET_FROM_STRETCH
2114 || it
.method
== GET_FROM_COMPOSITION
);
2116 reseat_at_previous_visible_line_start (&it
);
2117 it
.current_x
= it
.hpos
= 0;
2118 /* Temporarily disable selective display so we don't move too far */
2119 oselective
= it
.selective
;
2121 move_it_to (&it
, PT
, -1, -1, -1, MOVE_TO_POS
);
2122 it
.selective
= oselective
;
2124 /* Move back if we got too far. This may happen if
2125 truncate-lines is on and PT is beyond right margin.
2126 Don't go back if the overshoot is expected (see above). */
2127 if (IT_CHARPOS (it
) > it_start
&& XINT (lines
) > 0
2128 && (!it_overshoot_expected
2129 || (it_overshoot_expected
< 0
2130 && it
.method
== GET_FROM_BUFFER
2132 move_it_by_lines (&it
, -1, 0);
2135 /* Do this even if LINES is 0, so that we move back
2136 to the beginning of the current line as we ought. */
2137 if (XINT (lines
) >= 0 || IT_CHARPOS (it
) > 0)
2138 move_it_by_lines (&it
, XINT (lines
), 0);
2140 SET_PT_BOTH (IT_CHARPOS (it
), IT_BYTEPOS (it
));
2143 if (BUFFERP (old_buffer
))
2144 w
->buffer
= old_buffer
;
2146 RETURN_UNGCPRO (make_number (it
.vpos
));
2151 /* File's initialization. */
2156 DEFVAR_BOOL ("indent-tabs-mode", &indent_tabs_mode
,
2157 doc
: /* *Indentation can insert tabs if this is non-nil.
2158 Setting this variable automatically makes it local to the current buffer. */);
2159 indent_tabs_mode
= 1;
2161 defsubr (&Scurrent_indentation
);
2162 defsubr (&Sindent_to
);
2163 defsubr (&Scurrent_column
);
2164 defsubr (&Smove_to_column
);
2165 defsubr (&Svertical_motion
);
2166 defsubr (&Scompute_motion
);
2169 /* arch-tag: 9adfea44-71f7-4988-8ee3-96da15c502cc
2170 (do not change this comment) */