/* Indentation functions. Copyright (C) 1985, 1986, 1987, 1988, 1993, 1994, 1995, 1998, 2000, 2001, 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc. This file is part of GNU Emacs. GNU Emacs is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version. GNU Emacs is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with GNU Emacs; see the file COPYING. If not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ #include #include "lisp.h" #include "buffer.h" #include "charset.h" #include "category.h" #include "indent.h" #include "keyboard.h" #include "frame.h" #include "window.h" #include "termchar.h" #include "termopts.h" #include "disptab.h" #include "intervals.h" #include "region-cache.h" /* Indentation can insert tabs if this is non-zero; otherwise always uses spaces. */ int indent_tabs_mode; #define CR 015 /* These three values memorize the current column to avoid recalculation. */ /* Last value returned by current_column. Some things in set last_known_column_point to -1 to mark the memorized value as invalid. */ double last_known_column; /* Value of point when current_column was called. */ int last_known_column_point; /* Value of MODIFF when current_column was called. */ int last_known_column_modified; static double current_column_1 P_ ((void)); static double position_indentation P_ ((int)); /* Cache of beginning of line found by the last call of current_column. */ int current_column_bol_cache; /* Get the display table to use for the current buffer. */ struct Lisp_Char_Table * buffer_display_table () { Lisp_Object thisbuf; thisbuf = current_buffer->display_table; if (DISP_TABLE_P (thisbuf)) return XCHAR_TABLE (thisbuf); if (DISP_TABLE_P (Vstandard_display_table)) return XCHAR_TABLE (Vstandard_display_table); return 0; } /* Width run cache considerations. */ /* Return the width of character C under display table DP. */ static int character_width (c, dp) int c; struct Lisp_Char_Table *dp; { Lisp_Object elt; /* These width computations were determined by examining the cases in display_text_line. */ /* Everything can be handled by the display table, if it's present and the element is right. */ if (dp && (elt = DISP_CHAR_VECTOR (dp, c), VECTORP (elt))) return XVECTOR (elt)->size; /* Some characters are special. */ if (c == '\n' || c == '\t' || c == '\015') return 0; /* Printing characters have width 1. */ else if (c >= 040 && c < 0177) return 1; /* Everybody else (control characters, metacharacters) has other widths. We could return their actual widths here, but they depend on things like ctl_arrow and crud like that, and they're not very common at all. So we'll just claim we don't know their widths. */ else return 0; } /* Return true iff the display table DISPTAB specifies the same widths for characters as WIDTHTAB. We use this to decide when to invalidate the buffer's width_run_cache. */ int disptab_matches_widthtab (disptab, widthtab) struct Lisp_Char_Table *disptab; struct Lisp_Vector *widthtab; { int i; if (widthtab->size != 256) abort (); for (i = 0; i < 256; i++) if (character_width (i, disptab) != XFASTINT (widthtab->contents[i])) return 0; return 1; } /* Recompute BUF's width table, using the display table DISPTAB. */ void recompute_width_table (buf, disptab) struct buffer *buf; struct Lisp_Char_Table *disptab; { int i; struct Lisp_Vector *widthtab; if (!VECTORP (buf->width_table)) buf->width_table = Fmake_vector (make_number (256), make_number (0)); widthtab = XVECTOR (buf->width_table); if (widthtab->size != 256) abort (); for (i = 0; i < 256; i++) XSETFASTINT (widthtab->contents[i], character_width (i, disptab)); } /* Allocate or free the width run cache, as requested by the current state of current_buffer's cache_long_line_scans variable. */ static void width_run_cache_on_off () { if (NILP (current_buffer->cache_long_line_scans) /* And, for the moment, this feature doesn't work on multibyte characters. */ || !NILP (current_buffer->enable_multibyte_characters)) { /* It should be off. */ if (current_buffer->width_run_cache) { free_region_cache (current_buffer->width_run_cache); current_buffer->width_run_cache = 0; current_buffer->width_table = Qnil; } } else { /* It should be on. */ if (current_buffer->width_run_cache == 0) { current_buffer->width_run_cache = new_region_cache (); recompute_width_table (current_buffer, buffer_display_table ()); } } } /* Skip some invisible characters starting from POS. This includes characters invisible because of text properties and characters invisible because of overlays. If position POS is followed by invisible characters, skip some of them and return the position after them. Otherwise return POS itself. Set *NEXT_BOUNDARY_P to the next position at which it will be necessary to call this function again. Don't scan past TO, and don't set *NEXT_BOUNDARY_P to a value greater than TO. If WINDOW is non-nil, and this buffer is displayed in WINDOW, take account of overlays that apply only in WINDOW. We don't necessarily skip all the invisible characters after POS because that could take a long time. We skip a reasonable number which can be skipped quickly. If there might be more invisible characters immediately following, then *NEXT_BOUNDARY_P will equal the return value. */ int skip_invisible (pos, next_boundary_p, to, window) int pos; int *next_boundary_p; int to; Lisp_Object window; { Lisp_Object prop, position, overlay_limit, proplimit; Lisp_Object buffer, tmp; int end, inv_p; XSETFASTINT (position, pos); XSETBUFFER (buffer, current_buffer); /* Give faster response for overlay lookup near POS. */ recenter_overlay_lists (current_buffer, pos); /* We must not advance farther than the next overlay change. The overlay change might change the invisible property; or there might be overlay strings to be displayed there. */ overlay_limit = Fnext_overlay_change (position); /* As for text properties, this gives a lower bound for where the invisible text property could change. */ proplimit = Fnext_property_change (position, buffer, Qt); if (XFASTINT (overlay_limit) < XFASTINT (proplimit)) proplimit = overlay_limit; /* PROPLIMIT is now a lower bound for the next change in invisible status. If that is plenty far away, use that lower bound. */ if (XFASTINT (proplimit) > pos + 100 || XFASTINT (proplimit) >= to) *next_boundary_p = XFASTINT (proplimit); /* Otherwise, scan for the next `invisible' property change. */ else { /* Don't scan terribly far. */ XSETFASTINT (proplimit, min (pos + 100, to)); /* No matter what. don't go past next overlay change. */ if (XFASTINT (overlay_limit) < XFASTINT (proplimit)) proplimit = overlay_limit; tmp = Fnext_single_property_change (position, Qinvisible, buffer, proplimit); end = XFASTINT (tmp); #if 0 /* Don't put the boundary in the middle of multibyte form if there is no actual property change. */ if (end == pos + 100 && !NILP (current_buffer->enable_multibyte_characters) && end < ZV) while (pos < end && !CHAR_HEAD_P (POS_ADDR (end))) end--; #endif *next_boundary_p = end; } /* if the `invisible' property is set, we can skip to the next property change */ prop = Fget_char_property (position, Qinvisible, (!NILP (window) && EQ (XWINDOW (window)->buffer, buffer)) ? window : buffer); inv_p = TEXT_PROP_MEANS_INVISIBLE (prop); /* When counting columns (window == nil), don't skip over ellipsis text. */ if (NILP (window) ? inv_p == 1 : inv_p) return *next_boundary_p; return pos; } /* If a composition starts at POS/POS_BYTE and it doesn't stride over POINT, set *LEN / *LEN_BYTE to the character and byte lengths, *WIDTH to the width, and return 1. Otherwise, return 0. */ static int check_composition (pos, pos_byte, point, len, len_byte, width) int pos, pos_byte, point; int *len, *len_byte, *width; { Lisp_Object prop; int start, end; int id; if (! find_composition (pos, -1, &start, &end, &prop, Qnil) || pos != start || point < end || !COMPOSITION_VALID_P (start, end, prop)) return 0; if ((id = get_composition_id (pos, pos_byte, end - pos, prop, Qnil)) < 0) return 0; *len = COMPOSITION_LENGTH (prop); *len_byte = CHAR_TO_BYTE (end) - pos_byte; *width = composition_table[id]->width; return 1; } /* Set variables WIDTH and BYTES for a multibyte sequence starting at P. DP is a display table or NULL. This macro is used in current_column_1, Fmove_to_column, and compute_motion. */ #define MULTIBYTE_BYTES_WIDTH(p, dp) \ do { \ int c; \ \ wide_column = 0; \ c = STRING_CHAR_AND_LENGTH (p, MAX_MULTIBYTE_LENGTH, bytes); \ if (BYTES_BY_CHAR_HEAD (*p) != bytes) \ width = bytes * 4; \ else \ { \ if (dp != 0 && VECTORP (DISP_CHAR_VECTOR (dp, c))) \ width = XVECTOR (DISP_CHAR_VECTOR (dp, c))->size; \ else \ width = WIDTH_BY_CHAR_HEAD (*p); \ if (width > 1) \ wide_column = width; \ } \ } while (0) DEFUN ("current-column", Fcurrent_column, Scurrent_column, 0, 0, 0, doc: /* Return the horizontal position of point. Beginning of line is column 0. This is calculated by adding together the widths of all the displayed representations of the character between the start of the previous line and point (eg. control characters will have a width of 2 or 4, tabs will have a variable width). Ignores finite width of frame, which means that this function may return values greater than (frame-width). Whether the line is visible (if `selective-display' is t) has no effect; however, ^M is treated as end of line when `selective-display' is t. Text that has an invisible property is considered as having width 0, unless `buffer-invisibility-spec' specifies that it is replaced by an ellipsis. */) () { Lisp_Object temp; XSETFASTINT (temp, (int) current_column ()); /* iftc */ return temp; } /* Cancel any recorded value of the horizontal position. */ void invalidate_current_column () { last_known_column_point = 0; } double current_column () { register int col; register unsigned char *ptr, *stop; register int tab_seen; int post_tab; register int c; register int tab_width = XINT (current_buffer->tab_width); int ctl_arrow = !NILP (current_buffer->ctl_arrow); register struct Lisp_Char_Table *dp = buffer_display_table (); if (PT == last_known_column_point && MODIFF == last_known_column_modified) return last_known_column; /* If the buffer has overlays, text properties, or multibyte characters, use a more general algorithm. */ if (BUF_INTERVALS (current_buffer) || current_buffer->overlays_before || current_buffer->overlays_after || Z != Z_BYTE) return current_column_1 (); /* Scan backwards from point to the previous newline, counting width. Tab characters are the only complicated case. */ /* Make a pointer for decrementing through the chars before point. */ ptr = BYTE_POS_ADDR (PT_BYTE - 1) + 1; /* Make a pointer to where consecutive chars leave off, going backwards from point. */ if (PT == BEGV) stop = ptr; else if (PT <= GPT || BEGV > GPT) stop = BEGV_ADDR; else stop = GAP_END_ADDR; if (tab_width <= 0 || tab_width > 1000) tab_width = 8; col = 0, tab_seen = 0, post_tab = 0; while (1) { EMACS_INT i, n; Lisp_Object charvec; if (ptr == stop) { /* We stopped either for the beginning of the buffer or for the gap. */ if (ptr == BEGV_ADDR) break; /* It was the gap. Jump back over it. */ stop = BEGV_ADDR; ptr = GPT_ADDR; /* Check whether that brings us to beginning of buffer. */ if (BEGV >= GPT) break; } c = *--ptr; if (dp && VECTORP (DISP_CHAR_VECTOR (dp, c))) { charvec = DISP_CHAR_VECTOR (dp, c); n = ASIZE (charvec); } else { charvec = Qnil; n = 1; } for (i = n - 1; i >= 0; --i) { if (VECTORP (charvec)) { /* This should be handled the same as next_element_from_display_vector does it. */ Lisp_Object entry = AREF (charvec, i); if (INTEGERP (entry) && GLYPH_CHAR_VALID_P (XFASTINT (entry))) c = FAST_GLYPH_CHAR (XFASTINT (entry)); else c = ' '; } if (c >= 040 && c < 0177) col++; else if (c == '\n' || (c == '\r' && EQ (current_buffer->selective_display, Qt))) { ptr++; goto start_of_line_found; } else if (c == '\t') { if (tab_seen) col = ((col + tab_width) / tab_width) * tab_width; post_tab += col; col = 0; tab_seen = 1; } else if (VECTORP (charvec)) /* With a display table entry, C is displayed as is, and not displayed as \NNN or as ^N. If C is a single-byte character, it takes one column. If C is multi-byte in an unibyte buffer, it's translated to unibyte, so it also takes one column. */ ++col; else col += (ctl_arrow && c < 0200) ? 2 : 4; } } start_of_line_found: if (tab_seen) { col = ((col + tab_width) / tab_width) * tab_width; col += post_tab; } if (ptr == BEGV_ADDR) current_column_bol_cache = BEGV; else current_column_bol_cache = BYTE_TO_CHAR (PTR_BYTE_POS (ptr)); last_known_column = col; last_known_column_point = PT; last_known_column_modified = MODIFF; return col; } /* Return the column number of position POS by scanning forward from the beginning of the line. This function handles characters that are invisible due to text properties or overlays. */ static double current_column_1 () { register int tab_width = XINT (current_buffer->tab_width); register int ctl_arrow = !NILP (current_buffer->ctl_arrow); register struct Lisp_Char_Table *dp = buffer_display_table (); int multibyte = !NILP (current_buffer->enable_multibyte_characters); /* Start the scan at the beginning of this line with column number 0. */ register int col = 0; int scan, scan_byte; int next_boundary; int opoint = PT, opoint_byte = PT_BYTE; scan_newline (PT, PT_BYTE, BEGV, BEGV_BYTE, -1, 1); current_column_bol_cache = PT; scan = PT, scan_byte = PT_BYTE; SET_PT_BOTH (opoint, opoint_byte); next_boundary = scan; if (tab_width <= 0 || tab_width > 1000) tab_width = 8; /* Scan forward to the target position. */ while (scan < opoint) { int c; /* Occasionally we may need to skip invisible text. */ while (scan == next_boundary) { int old_scan = scan; /* This updates NEXT_BOUNDARY to the next place where we might need to skip more invisible text. */ scan = skip_invisible (scan, &next_boundary, opoint, Qnil); if (scan >= opoint) goto endloop; if (scan != old_scan) scan_byte = CHAR_TO_BYTE (scan); } /* Check composition sequence. */ { int len, len_byte, width; if (check_composition (scan, scan_byte, opoint, &len, &len_byte, &width)) { scan += len; scan_byte += len_byte; if (scan <= opoint) col += width; continue; } } c = FETCH_BYTE (scan_byte); if (dp != 0 && ! (multibyte && BASE_LEADING_CODE_P (c)) && VECTORP (DISP_CHAR_VECTOR (dp, c))) { Lisp_Object charvec; EMACS_INT i, n; /* This character is displayed using a vector of glyphs. Update the column based on those glyphs. */ charvec = DISP_CHAR_VECTOR (dp, c); n = ASIZE (charvec); for (i = 0; i < n; i++) { /* This should be handled the same as next_element_from_display_vector does it. */ Lisp_Object entry; entry = AREF (charvec, i); if (INTEGERP (entry) && GLYPH_CHAR_VALID_P (XFASTINT (entry))) c = FAST_GLYPH_CHAR (XFASTINT (entry)); else c = ' '; if (c == '\n') goto endloop; if (c == '\r' && EQ (current_buffer->selective_display, Qt)) goto endloop; if (c == '\t') { col += tab_width; col = col / tab_width * tab_width; } else ++col; } } else { /* The display table says nothing for this character. Display it as itself. */ if (c == '\n') goto endloop; if (c == '\r' && EQ (current_buffer->selective_display, Qt)) goto endloop; if (c == '\t') { col += tab_width; col = col / tab_width * tab_width; } else if (multibyte && BASE_LEADING_CODE_P (c)) { unsigned char *ptr; int bytes, width, wide_column; ptr = BYTE_POS_ADDR (scan_byte); MULTIBYTE_BYTES_WIDTH (ptr, dp); scan_byte += bytes; /* Subtract one to compensate for the increment that is going to happen below. */ scan_byte--; col += width; } else if (ctl_arrow && (c < 040 || c == 0177)) col += 2; else if (c < 040 || c >= 0177) col += 4; else col++; } scan++; scan_byte++; } endloop: last_known_column = col; last_known_column_point = PT; last_known_column_modified = MODIFF; return col; } #if 0 /* Not used. */ /* Return the width in columns of the part of STRING from BEG to END. If BEG is nil, that stands for the beginning of STRING. If END is nil, that stands for the end of STRING. */ static double string_display_width (string, beg, end) Lisp_Object string, beg, end; { register int col; register unsigned char *ptr, *stop; register int tab_seen; int post_tab; register int c; register int tab_width = XINT (current_buffer->tab_width); int ctl_arrow = !NILP (current_buffer->ctl_arrow); register struct Lisp_Char_Table *dp = buffer_display_table (); int b, e; if (NILP (end)) e = SCHARS (string); else { CHECK_NUMBER (end); e = XINT (end); } if (NILP (beg)) b = 0; else { CHECK_NUMBER (beg); b = XINT (beg); } /* Make a pointer for decrementing through the chars before point. */ ptr = SDATA (string) + e; /* Make a pointer to where consecutive chars leave off, going backwards from point. */ stop = SDATA (string) + b; if (tab_width <= 0 || tab_width > 1000) tab_width = 8; col = 0, tab_seen = 0, post_tab = 0; while (1) { if (ptr == stop) break; c = *--ptr; if (dp != 0 && VECTORP (DISP_CHAR_VECTOR (dp, c))) col += XVECTOR (DISP_CHAR_VECTOR (dp, c))->size; else if (c >= 040 && c < 0177) col++; else if (c == '\n') break; else if (c == '\t') { if (tab_seen) col = ((col + tab_width) / tab_width) * tab_width; post_tab += col; col = 0; tab_seen = 1; } else col += (ctl_arrow && c < 0200) ? 2 : 4; } if (tab_seen) { col = ((col + tab_width) / tab_width) * tab_width; col += post_tab; } return col; } #endif /* 0 */ DEFUN ("indent-to", Findent_to, Sindent_to, 1, 2, "NIndent to column: ", doc: /* Indent from point with tabs and spaces until COLUMN is reached. Optional second argument MINIMUM says always do at least MINIMUM spaces even if that goes past COLUMN; by default, MINIMUM is zero. */) (column, minimum) Lisp_Object column, minimum; { int mincol; register int fromcol; register int tab_width = XINT (current_buffer->tab_width); CHECK_NUMBER (column); if (NILP (minimum)) XSETFASTINT (minimum, 0); CHECK_NUMBER (minimum); fromcol = current_column (); mincol = fromcol + XINT (minimum); if (mincol < XINT (column)) mincol = XINT (column); if (fromcol == mincol) return make_number (mincol); if (tab_width <= 0 || tab_width > 1000) tab_width = 8; if (indent_tabs_mode) { Lisp_Object n; XSETFASTINT (n, mincol / tab_width - fromcol / tab_width); if (XFASTINT (n) != 0) { Finsert_char (make_number ('\t'), n, Qt); fromcol = (mincol / tab_width) * tab_width; } } XSETFASTINT (column, mincol - fromcol); Finsert_char (make_number (' '), column, Qt); last_known_column = mincol; last_known_column_point = PT; last_known_column_modified = MODIFF; XSETINT (column, mincol); return column; } static double position_indentation P_ ((int)); DEFUN ("current-indentation", Fcurrent_indentation, Scurrent_indentation, 0, 0, 0, doc: /* Return the indentation of the current line. This is the horizontal position of the character following any initial whitespace. */) () { Lisp_Object val; int opoint = PT, opoint_byte = PT_BYTE; scan_newline (PT, PT_BYTE, BEGV, BEGV_BYTE, -1, 1); XSETFASTINT (val, (int) position_indentation (PT_BYTE)); /* iftc */ SET_PT_BOTH (opoint, opoint_byte); return val; } static double position_indentation (pos_byte) register int pos_byte; { register int column = 0; register int tab_width = XINT (current_buffer->tab_width); register unsigned char *p; register unsigned char *stop; unsigned char *start; int next_boundary_byte = pos_byte; int ceiling = next_boundary_byte; if (tab_width <= 0 || tab_width > 1000) tab_width = 8; p = BYTE_POS_ADDR (pos_byte); /* STOP records the value of P at which we will need to think about the gap, or about invisible text, or about the end of the buffer. */ stop = p; /* START records the starting value of P. */ start = p; while (1) { while (p == stop) { int stop_pos_byte; /* If we have updated P, set POS_BYTE to match. The first time we enter the loop, POS_BYTE is already right. */ if (p != start) pos_byte = PTR_BYTE_POS (p); /* Consider the various reasons STOP might have been set here. */ if (pos_byte == ZV_BYTE) return column; if (pos_byte == next_boundary_byte) { int next_boundary; int pos = BYTE_TO_CHAR (pos_byte); pos = skip_invisible (pos, &next_boundary, ZV, Qnil); pos_byte = CHAR_TO_BYTE (pos); next_boundary_byte = CHAR_TO_BYTE (next_boundary); } if (pos_byte >= ceiling) ceiling = BUFFER_CEILING_OF (pos_byte) + 1; /* Compute the next place we need to stop and think, and set STOP accordingly. */ stop_pos_byte = min (ceiling, next_boundary_byte); /* The -1 and +1 arrange to point at the first byte of gap (if STOP_POS_BYTE is the position of the gap) rather than at the data after the gap. */ stop = BYTE_POS_ADDR (stop_pos_byte - 1) + 1; p = BYTE_POS_ADDR (pos_byte); } switch (*p++) { case 0240: if (! NILP (current_buffer->enable_multibyte_characters)) return column; case ' ': column++; break; case '\t': column += tab_width - column % tab_width; break; default: if (ASCII_BYTE_P (p[-1]) || NILP (current_buffer->enable_multibyte_characters)) return column; { int c; pos_byte = PTR_BYTE_POS (p - 1); c = FETCH_MULTIBYTE_CHAR (pos_byte); if (CHAR_HAS_CATEGORY (c, ' ')) { column++; INC_POS (pos_byte); p = BYTE_POS_ADDR (pos_byte); } else return column; } } } } /* Test whether the line beginning at POS is indented beyond COLUMN. Blank lines are treated as if they had the same indentation as the preceding line. */ int indented_beyond_p (pos, pos_byte, column) int pos, pos_byte; double column; { double val; int opoint = PT, opoint_byte = PT_BYTE; SET_PT_BOTH (pos, pos_byte); while (PT > BEGV && FETCH_BYTE (PT_BYTE) == '\n') scan_newline (PT - 1, PT_BYTE - 1, BEGV, BEGV_BYTE, -1, 0); val = position_indentation (PT_BYTE); SET_PT_BOTH (opoint, opoint_byte); return val >= column; /* hmm, float comparison */ } DEFUN ("move-to-column", Fmove_to_column, Smove_to_column, 1, 2, "p", doc: /* Move point to column COLUMN in the current line. The column of a character is calculated by adding together the widths as displayed of the previous characters in the line. This function ignores line-continuation; there is no upper limit on the column number a character can have and horizontal scrolling has no effect. If specified column is within a character, point goes after that character. If it's past end of line, point goes to end of line. A non-nil second (optional) argument FORCE means, if COLUMN is in the middle of a tab character, change it to spaces. In addition, if FORCE is t, and the line is too short to reach column COLUMN, add spaces/tabs to get there. The return value is the current column. */) (column, force) Lisp_Object column, force; { register int pos; register int col = current_column (); register int goal; register int end; register int tab_width = XINT (current_buffer->tab_width); register int ctl_arrow = !NILP (current_buffer->ctl_arrow); register struct Lisp_Char_Table *dp = buffer_display_table (); register int multibyte = !NILP (current_buffer->enable_multibyte_characters); Lisp_Object val; int prev_col = 0; int c = 0; int next_boundary, pos_byte; if (tab_width <= 0 || tab_width > 1000) tab_width = 8; CHECK_NATNUM (column); goal = XINT (column); pos = PT; pos_byte = PT_BYTE; end = ZV; next_boundary = pos; /* If we're starting past the desired column, back up to beginning of line and scan from there. */ if (col > goal) { end = pos; pos = current_column_bol_cache; pos_byte = CHAR_TO_BYTE (pos); col = 0; } while (pos < end) { while (pos == next_boundary) { int prev = pos; pos = skip_invisible (pos, &next_boundary, end, Qnil); if (pos != prev) pos_byte = CHAR_TO_BYTE (pos); if (pos >= end) goto endloop; } /* Test reaching the goal column. We do this after skipping invisible characters, so that we put point before the character on which the cursor will appear. */ if (col >= goal) break; /* Check composition sequence. */ { int len, len_byte, width; if (check_composition (pos, pos_byte, Z, &len, &len_byte, &width)) { pos += len; pos_byte += len_byte; col += width; continue; } } c = FETCH_BYTE (pos_byte); /* See if there is a display table and it relates to this character. */ if (dp != 0 && ! (multibyte && BASE_LEADING_CODE_P (c)) && VECTORP (DISP_CHAR_VECTOR (dp, c))) { Lisp_Object charvec; EMACS_INT i, n; /* This character is displayed using a vector of glyphs. Update the position based on those glyphs. */ charvec = DISP_CHAR_VECTOR (dp, c); n = ASIZE (charvec); for (i = 0; i < n; i++) { /* This should be handled the same as next_element_from_display_vector does it. */ Lisp_Object entry; entry = AREF (charvec, i); if (INTEGERP (entry) && GLYPH_CHAR_VALID_P (XFASTINT (entry))) c = FAST_GLYPH_CHAR (XFASTINT (entry)); else c = ' '; if (c == '\n') goto endloop; if (c == '\r' && EQ (current_buffer->selective_display, Qt)) goto endloop; if (c == '\t') { prev_col = col; col += tab_width; col = col / tab_width * tab_width; } else ++col; } } else { /* The display table doesn't affect this character; it displays as itself. */ if (c == '\n') goto endloop; if (c == '\r' && EQ (current_buffer->selective_display, Qt)) goto endloop; if (c == '\t') { prev_col = col; col += tab_width; col = col / tab_width * tab_width; } else if (ctl_arrow && (c < 040 || c == 0177)) col += 2; else if (c < 040 || c == 0177) col += 4; else if (c < 0177) col++; else if (multibyte && BASE_LEADING_CODE_P (c)) { /* Start of multi-byte form. */ unsigned char *ptr; int bytes, width, wide_column; ptr = BYTE_POS_ADDR (pos_byte); MULTIBYTE_BYTES_WIDTH (ptr, dp); pos_byte += bytes - 1; col += width; } else col += 4; } pos++; pos_byte++; } endloop: SET_PT_BOTH (pos, pos_byte); /* If a tab char made us overshoot, change it to spaces and scan through it again. */ if (!NILP (force) && col > goal && c == '\t' && prev_col < goal) { int goal_pt, goal_pt_byte; /* Insert spaces in front of the tab to reach GOAL. Do this first so that a marker at the end of the tab gets adjusted. */ SET_PT_BOTH (PT - 1, PT_BYTE - 1); Finsert_char (make_number (' '), make_number (goal - prev_col), Qt); /* Now delete the tab, and indent to COL. */ del_range (PT, PT + 1); goal_pt = PT; goal_pt_byte = PT_BYTE; Findent_to (make_number (col), Qnil); SET_PT_BOTH (goal_pt, goal_pt_byte); /* Set the last_known... vars consistently. */ col = goal; } /* If line ends prematurely, add space to the end. */ if (col < goal && EQ (force, Qt)) Findent_to (make_number (col = goal), Qnil); last_known_column = col; last_known_column_point = PT; last_known_column_modified = MODIFF; XSETFASTINT (val, col); return val; } /* compute_motion: compute buffer posn given screen posn and vice versa */ struct position val_compute_motion; /* Scan the current buffer forward from offset FROM, pretending that this is at line FROMVPOS, column FROMHPOS, until reaching buffer offset TO or line TOVPOS, column TOHPOS (whichever comes first), and return the ending buffer position and screen location. If we can't hit the requested column exactly (because of a tab or other multi-column character), overshoot. DID_MOTION is 1 if FROMHPOS has already accounted for overlay strings at FROM. This is the case if FROMVPOS and FROMVPOS came from an earlier call to compute_motion. The other common case is that FROMHPOS is zero and FROM is a position that "belongs" at column zero, but might be shifted by overlay strings; in this case DID_MOTION should be 0. WIDTH is the number of columns available to display text; compute_motion uses this to handle continuation lines and such. If WIDTH is -1, use width of window's text area adjusted for continuation glyph when needed. HSCROLL is the number of columns not being displayed at the left margin; this is usually taken from a window's hscroll member. TAB_OFFSET is the number of columns of the first tab that aren't being displayed, perhaps because of a continuation line or something. compute_motion returns a pointer to a struct position. The bufpos member gives the buffer position at the end of the scan, and hpos and vpos give its cartesian location. prevhpos is the column at which the character before bufpos started, and contin is non-zero if we reached the current line by continuing the previous. Note that FROMHPOS and TOHPOS should be expressed in real screen columns, taking HSCROLL and the truncation glyph at the left margin into account. That is, beginning-of-line moves you to the hpos -HSCROLL + (HSCROLL > 0). For example, to find the buffer position of column COL of line LINE of a certain window, pass the window's starting location as FROM and the window's upper-left coordinates as FROMVPOS and FROMHPOS. Pass the buffer's ZV as TO, to limit the scan to the end of the visible section of the buffer, and pass LINE and COL as TOVPOS and TOHPOS. When displaying in window w, a typical formula for WIDTH is: window_width - 1 - (has_vertical_scroll_bars ? WINDOW_CONFIG_SCROLL_BAR_COLS (window) : (window_width + window_left != frame_cols)) where window_width is XFASTINT (w->total_cols), window_left is XFASTINT (w->left_col), has_vertical_scroll_bars is WINDOW_HAS_VERTICAL_SCROLL_BAR (window) and frame_cols = FRAME_COLS (XFRAME (window->frame)) Or you can let window_box_text_cols do this all for you, and write: window_box_text_cols (w) - 1 The `-1' accounts for the continuation-line backslashes; the rest accounts for window borders if the window is split horizontally, and the scroll bars if they are turned on. */ struct position * compute_motion (from, fromvpos, fromhpos, did_motion, to, tovpos, tohpos, width, hscroll, tab_offset, win) int from, fromvpos, fromhpos, to, tovpos, tohpos; int did_motion; register int width; int hscroll, tab_offset; struct window *win; { register int hpos = fromhpos; register int vpos = fromvpos; register int pos; int pos_byte; register int c = 0; register int tab_width = XFASTINT (current_buffer->tab_width); register int ctl_arrow = !NILP (current_buffer->ctl_arrow); register struct Lisp_Char_Table *dp = window_display_table (win); int selective = (INTEGERP (current_buffer->selective_display) ? XINT (current_buffer->selective_display) : !NILP (current_buffer->selective_display) ? -1 : 0); int selective_rlen = (selective && dp && VECTORP (DISP_INVIS_VECTOR (dp)) ? XVECTOR (DISP_INVIS_VECTOR (dp))->size : 0); /* The next location where the `invisible' property changes, or an overlay starts or ends. */ int next_boundary = from; /* For computing runs of characters with similar widths. Invariant: width_run_width is zero, or all the characters from width_run_start to width_run_end have a fixed width of width_run_width. */ int width_run_start = from; int width_run_end = from; int width_run_width = 0; Lisp_Object *width_table; Lisp_Object buffer; /* The next buffer pos where we should consult the width run cache. */ int next_width_run = from; Lisp_Object window; int multibyte = !NILP (current_buffer->enable_multibyte_characters); /* If previous char scanned was a wide character, this is the column where it ended. Otherwise, this is 0. */ int wide_column_end_hpos = 0; int prev_pos; /* Previous buffer position. */ int prev_pos_byte; /* Previous buffer position. */ int prev_hpos = 0; int prev_vpos = 0; int contin_hpos; /* HPOS of last column of continued line. */ int prev_tab_offset; /* Previous tab offset. */ int continuation_glyph_width; XSETBUFFER (buffer, current_buffer); XSETWINDOW (window, win); width_run_cache_on_off (); if (dp == buffer_display_table ()) width_table = (VECTORP (current_buffer->width_table) ? XVECTOR (current_buffer->width_table)->contents : 0); else /* If the window has its own display table, we can't use the width run cache, because that's based on the buffer's display table. */ width_table = 0; if (tab_width <= 0 || tab_width > 1000) tab_width = 8; /* Negative width means use all available text columns. */ if (width < 0) { width = window_box_text_cols (win); /* We must make room for continuation marks if we don't have fringes. */ #ifdef HAVE_WINDOW_SYSTEM if (!FRAME_WINDOW_P (XFRAME (win->frame))) #endif width -= 1; } continuation_glyph_width = 1; #ifdef HAVE_WINDOW_SYSTEM if (FRAME_WINDOW_P (XFRAME (win->frame))) continuation_glyph_width = 0; /* In the fringe. */ #endif immediate_quit = 1; QUIT; pos = prev_pos = from; pos_byte = prev_pos_byte = CHAR_TO_BYTE (from); contin_hpos = 0; prev_tab_offset = tab_offset; while (1) { while (pos == next_boundary) { int pos_here = pos; int newpos; /* Don't skip invisible if we are already at the margin. */ if (vpos > tovpos || (vpos == tovpos && hpos >= tohpos)) { if (contin_hpos && prev_hpos == 0 && hpos > tohpos && (contin_hpos == width || wide_column_end_hpos > width)) { /* Line breaks because we can't put the character at the previous line any more. It is not the multi-column character continued in middle. Go back to previous buffer position, screen position, and set tab offset to previous value. It's the beginning of the line. */ pos = prev_pos; pos_byte = prev_pos_byte; hpos = prev_hpos; vpos = prev_vpos; tab_offset = prev_tab_offset; } break; } /* If the caller says that the screen position came from an earlier call to compute_motion, then we've already accounted for the overlay strings at point. This is only true the first time through, so clear the flag after testing it. */ if (!did_motion) /* We need to skip past the overlay strings. Currently those strings must not contain TAB; if we want to relax that restriction, something will have to be changed here. */ { unsigned char *ovstr; int ovlen = overlay_strings (pos, win, &ovstr); hpos += ((multibyte && ovlen > 0) ? strwidth (ovstr, ovlen) : ovlen); } did_motion = 0; if (pos >= to) break; /* Advance POS past invisible characters (but not necessarily all that there are here), and store in next_boundary the next position where we need to call skip_invisible. */ newpos = skip_invisible (pos, &next_boundary, to, window); if (newpos >= to) { pos = min (to, newpos); pos_byte = CHAR_TO_BYTE (pos); goto after_loop; } if (newpos != pos_here) { pos = newpos; pos_byte = CHAR_TO_BYTE (pos); } } /* Handle right margin. */ /* Note on a wide-column character. Characters are classified into the following three categories according to the width (columns occupied on screen). (1) single-column character: ex. `a' (2) multi-column character: ex. `^A', TAB, `\033' (3) wide-column character: ex. Japanese character, Chinese character (In the following example, `W_' stands for them.) Multi-column characters can be divided around the right margin, but wide-column characters cannot. NOTE: (*) The cursor is placed on the next character after the point. ---------- abcdefghi\ j ^---- next after the point ^--- next char. after the point. ---------- In case of sigle-column character ---------- abcdefgh\\ 033 ^---- next after the point, next char. after the point. ---------- In case of multi-column character ---------- abcdefgh\\ W_ ^---- next after the point ^---- next char. after the point. ---------- In case of wide-column character The problem here is continuation at a wide-column character. In this case, the line may shorter less than WIDTH. And we find the continuation AFTER it occurs. */ if (hpos > width) { if (hscroll || (truncate_partial_width_windows && ((width + continuation_glyph_width) < FRAME_COLS (XFRAME (WINDOW_FRAME (win))))) || !NILP (current_buffer->truncate_lines)) { /* Truncating: skip to newline, unless we are already past TO (we need to go back below). */ if (pos <= to) { pos = find_before_next_newline (pos, to, 1); pos_byte = CHAR_TO_BYTE (pos); hpos = width; /* If we just skipped next_boundary, loop around in the main while and handle it. */ if (pos >= next_boundary) next_boundary = pos + 1; prev_hpos = width; prev_vpos = vpos; prev_tab_offset = tab_offset; } } else { /* Continuing. */ /* Remember the previous value. */ prev_tab_offset = tab_offset; if (wide_column_end_hpos > width) { hpos -= prev_hpos; tab_offset += prev_hpos; } else { tab_offset += width; hpos -= width; } vpos++; contin_hpos = prev_hpos; prev_hpos = 0; prev_vpos = vpos; } } /* Stop if past the target buffer position or screen position. */ if (pos > to) { /* Go back to the previous position. */ pos = prev_pos; pos_byte = prev_pos_byte; hpos = prev_hpos; vpos = prev_vpos; tab_offset = prev_tab_offset; /* NOTE on contin_hpos, hpos, and prev_hpos. ---------- abcdefgh\\ W_ ^---- contin_hpos | ^----- hpos \---- prev_hpos ---------- */ if (contin_hpos && prev_hpos == 0 && contin_hpos < width && !wide_column_end_hpos) { /* Line breaking occurs in the middle of multi-column character. Go back to previous line. */ hpos = contin_hpos; vpos = vpos - 1; } break; } if (vpos > tovpos || (vpos == tovpos && hpos >= tohpos)) { if (contin_hpos && prev_hpos == 0 && hpos > tohpos && (contin_hpos == width || wide_column_end_hpos > width)) { /* Line breaks because we can't put the character at the previous line any more. It is not the multi-column character continued in middle. Go back to previous buffer position, screen position, and set tab offset to previous value. It's the beginning of the line. */ pos = prev_pos; pos_byte = prev_pos_byte; hpos = prev_hpos; vpos = prev_vpos; tab_offset = prev_tab_offset; } break; } if (pos == ZV) /* We cannot go beyond ZV. Stop here. */ break; prev_hpos = hpos; prev_vpos = vpos; prev_pos = pos; prev_pos_byte = pos_byte; wide_column_end_hpos = 0; /* Consult the width run cache to see if we can avoid inspecting the text character-by-character. */ if (current_buffer->width_run_cache && pos >= next_width_run) { int run_end; int common_width = region_cache_forward (current_buffer, current_buffer->width_run_cache, pos, &run_end); /* A width of zero means the character's width varies (like a tab), is meaningless (like a newline), or we just don't want to skip over it for some other reason. */ if (common_width != 0) { int run_end_hpos; /* Don't go past the final buffer posn the user requested. */ if (run_end > to) run_end = to; run_end_hpos = hpos + (run_end - pos) * common_width; /* Don't go past the final horizontal position the user requested. */ if (vpos == tovpos && run_end_hpos > tohpos) { run_end = pos + (tohpos - hpos) / common_width; run_end_hpos = hpos + (run_end - pos) * common_width; } /* Don't go past the margin. */ if (run_end_hpos >= width) { run_end = pos + (width - hpos) / common_width; run_end_hpos = hpos + (run_end - pos) * common_width; } hpos = run_end_hpos; if (run_end > pos) prev_hpos = hpos - common_width; if (pos != run_end) { pos = run_end; pos_byte = CHAR_TO_BYTE (pos); } } next_width_run = run_end + 1; } /* We have to scan the text character-by-character. */ else { EMACS_INT i, n; Lisp_Object charvec; c = FETCH_BYTE (pos_byte); /* Check composition sequence. */ { int len, len_byte, width; if (check_composition (pos, pos_byte, to, &len, &len_byte, &width)) { pos += len; pos_byte += len_byte; hpos += width; continue; } } pos++, pos_byte++; /* Perhaps add some info to the width_run_cache. */ if (current_buffer->width_run_cache) { /* Is this character part of the current run? If so, extend the run. */ if (pos - 1 == width_run_end && XFASTINT (width_table[c]) == width_run_width) width_run_end = pos; /* The previous run is over, since this is a character at a different position, or a different width. */ else { /* Have we accumulated a run to put in the cache? (Currently, we only cache runs of width == 1). */ if (width_run_start < width_run_end && width_run_width == 1) know_region_cache (current_buffer, current_buffer->width_run_cache, width_run_start, width_run_end); /* Start recording a new width run. */ width_run_width = XFASTINT (width_table[c]); width_run_start = pos - 1; width_run_end = pos; } } if (dp != 0 && ! (multibyte && BASE_LEADING_CODE_P (c)) && VECTORP (DISP_CHAR_VECTOR (dp, c))) { charvec = DISP_CHAR_VECTOR (dp, c); n = ASIZE (charvec); } else { charvec = Qnil; n = 1; } for (i = n - 1; i >= 0; --i) { if (VECTORP (charvec)) { /* This should be handled the same as next_element_from_display_vector does it. */ Lisp_Object entry = AREF (charvec, i); if (INTEGERP (entry) && GLYPH_CHAR_VALID_P (XFASTINT (entry))) c = FAST_GLYPH_CHAR (XFASTINT (entry)); else c = ' '; } if (c >= 040 && c < 0177) hpos++; else if (c == '\t') { int tem = ((hpos + tab_offset + hscroll - (hscroll > 0)) % tab_width); if (tem < 0) tem += tab_width; hpos += tab_width - tem; } else if (c == '\n') { if (selective > 0 && indented_beyond_p (pos, pos_byte, (double) selective)) /* iftc */ { /* If (pos == to), we don't have to take care of selective display. */ if (pos < to) { /* Skip any number of invisible lines all at once */ do { pos = find_before_next_newline (pos, to, 1); if (pos < to) pos++; pos_byte = CHAR_TO_BYTE (pos); } while (pos < to && indented_beyond_p (pos, pos_byte, (double) selective)); /* iftc */ /* Allow for the " ..." that is displayed for them. */ if (selective_rlen) { hpos += selective_rlen; if (hpos >= width) hpos = width; } DEC_BOTH (pos, pos_byte); /* We have skipped the invis text, but not the newline after. */ } } else { /* A visible line. */ vpos++; hpos = 0; hpos -= hscroll; /* Count the truncation glyph on column 0 */ if (hscroll > 0) hpos += continuation_glyph_width; tab_offset = 0; } contin_hpos = 0; } else if (c == CR && selective < 0) { /* In selective display mode, everything from a ^M to the end of the line is invisible. Stop *before* the real newline. */ if (pos < to) { pos = find_before_next_newline (pos, to, 1); pos_byte = CHAR_TO_BYTE (pos); } /* If we just skipped next_boundary, loop around in the main while and handle it. */ if (pos > next_boundary) next_boundary = pos; /* Allow for the " ..." that is displayed for them. */ if (selective_rlen) { hpos += selective_rlen; if (hpos >= width) hpos = width; } } else if (multibyte && BASE_LEADING_CODE_P (c)) { /* Start of multi-byte form. */ unsigned char *ptr; int bytes, width, wide_column; pos_byte--; /* rewind POS_BYTE */ ptr = BYTE_POS_ADDR (pos_byte); MULTIBYTE_BYTES_WIDTH (ptr, dp); pos_byte += bytes; if (wide_column) wide_column_end_hpos = hpos + wide_column; hpos += width; } else if (VECTORP (charvec)) ++hpos; else hpos += (ctl_arrow && c < 0200) ? 2 : 4; } } } after_loop: /* Remember any final width run in the cache. */ if (current_buffer->width_run_cache && width_run_width == 1 && width_run_start < width_run_end) know_region_cache (current_buffer, current_buffer->width_run_cache, width_run_start, width_run_end); val_compute_motion.bufpos = pos; val_compute_motion.bytepos = pos_byte; val_compute_motion.hpos = hpos; val_compute_motion.vpos = vpos; if (contin_hpos && prev_hpos == 0) val_compute_motion.prevhpos = contin_hpos; else val_compute_motion.prevhpos = prev_hpos; /* We alalways handle all of them here; none of them remain to do. */ val_compute_motion.ovstring_chars_done = 0; /* Nonzero if have just continued a line */ val_compute_motion.contin = (contin_hpos && prev_hpos == 0); immediate_quit = 0; return &val_compute_motion; } DEFUN ("compute-motion", Fcompute_motion, Scompute_motion, 7, 7, 0, doc: /* Scan through the current buffer, calculating screen position. Scan the current buffer forward from offset FROM, assuming it is at position FROMPOS--a cons of the form (HPOS . VPOS)-- to position TO or position TOPOS--another cons of the form (HPOS . VPOS)-- and return the ending buffer position and screen location. If TOPOS is nil, the actual width and height of the window's text area are used. There are three additional arguments: WIDTH is the number of columns available to display text; this affects handling of continuation lines. A value of nil corresponds to the actual number of available text columns. OFFSETS is either nil or a cons cell (HSCROLL . TAB-OFFSET). HSCROLL is the number of columns not being displayed at the left margin; this is usually taken from a window's hscroll member. TAB-OFFSET is the number of columns of the first tab that aren't being displayed, perhaps because the line was continued within it. If OFFSETS is nil, HSCROLL and TAB-OFFSET are assumed to be zero. WINDOW is the window to operate on. It is used to choose the display table; if it is showing the current buffer, it is used also for deciding which overlay properties apply. Note that `compute-motion' always operates on the current buffer. The value is a list of five elements: (POS HPOS VPOS PREVHPOS CONTIN) POS is the buffer position where the scan stopped. VPOS is the vertical position where the scan stopped. HPOS is the horizontal position where the scan stopped. PREVHPOS is the horizontal position one character back from POS. CONTIN is t if a line was continued after (or within) the previous character. For example, to find the buffer position of column COL of line LINE of a certain window, pass the window's starting location as FROM and the window's upper-left coordinates as FROMPOS. Pass the buffer's (point-max) as TO, to limit the scan to the end of the visible section of the buffer, and pass LINE and COL as TOPOS. */) (from, frompos, to, topos, width, offsets, window) Lisp_Object from, frompos, to, topos; Lisp_Object width, offsets, window; { struct window *w; Lisp_Object bufpos, hpos, vpos, prevhpos; struct position *pos; int hscroll, tab_offset; CHECK_NUMBER_COERCE_MARKER (from); CHECK_CONS (frompos); CHECK_NUMBER_CAR (frompos); CHECK_NUMBER_CDR (frompos); CHECK_NUMBER_COERCE_MARKER (to); if (!NILP (topos)) { CHECK_CONS (topos); CHECK_NUMBER_CAR (topos); CHECK_NUMBER_CDR (topos); } if (!NILP (width)) CHECK_NUMBER (width); if (!NILP (offsets)) { CHECK_CONS (offsets); CHECK_NUMBER_CAR (offsets); CHECK_NUMBER_CDR (offsets); hscroll = XINT (XCAR (offsets)); tab_offset = XINT (XCDR (offsets)); } else hscroll = tab_offset = 0; if (NILP (window)) window = Fselected_window (); else CHECK_LIVE_WINDOW (window); w = XWINDOW (window); if (XINT (from) < BEGV || XINT (from) > ZV) args_out_of_range_3 (from, make_number (BEGV), make_number (ZV)); if (XINT (to) < BEGV || XINT (to) > ZV) args_out_of_range_3 (to, make_number (BEGV), make_number (ZV)); pos = compute_motion (XINT (from), XINT (XCDR (frompos)), XINT (XCAR (frompos)), 0, XINT (to), (NILP (topos) ? window_internal_height (w) : XINT (XCDR (topos))), (NILP (topos) ? (window_box_text_cols (w) - ( #ifdef HAVE_WINDOW_SYSTEM FRAME_WINDOW_P (XFRAME (w->frame)) ? 0 : #endif 1)) : XINT (XCAR (topos))), (NILP (width) ? -1 : XINT (width)), hscroll, tab_offset, XWINDOW (window)); XSETFASTINT (bufpos, pos->bufpos); XSETINT (hpos, pos->hpos); XSETINT (vpos, pos->vpos); XSETINT (prevhpos, pos->prevhpos); return Fcons (bufpos, Fcons (hpos, Fcons (vpos, Fcons (prevhpos, Fcons (pos->contin ? Qt : Qnil, Qnil))))); } /* Fvertical_motion and vmotion */ struct position val_vmotion; struct position * vmotion (from, vtarget, w) register int from, vtarget; struct window *w; { int hscroll = XINT (w->hscroll); struct position pos; /* vpos is cumulative vertical position, changed as from is changed */ register int vpos = 0; int prevline; register int first; int from_byte; int lmargin = hscroll > 0 ? 1 - hscroll : 0; int selective = (INTEGERP (current_buffer->selective_display) ? XINT (current_buffer->selective_display) : !NILP (current_buffer->selective_display) ? -1 : 0); Lisp_Object window; int start_hpos = 0; int did_motion; /* This is the object we use for fetching character properties. */ Lisp_Object text_prop_object; XSETWINDOW (window, w); /* If the window contains this buffer, use it for getting text properties. Otherwise use the current buffer as arg for doing that. */ if (EQ (w->buffer, Fcurrent_buffer ())) text_prop_object = window; else text_prop_object = Fcurrent_buffer (); if (vpos >= vtarget) { /* To move upward, go a line at a time until we have gone at least far enough. */ first = 1; while ((vpos > vtarget || first) && from > BEGV) { Lisp_Object propval; prevline = find_next_newline_no_quit (from - 1, -1); while (prevline > BEGV && ((selective > 0 && indented_beyond_p (prevline, CHAR_TO_BYTE (prevline), (double) selective)) /* iftc */ /* Watch out for newlines with `invisible' property. When moving upward, check the newline before. */ || (propval = Fget_char_property (make_number (prevline - 1), Qinvisible, text_prop_object), TEXT_PROP_MEANS_INVISIBLE (propval)))) prevline = find_next_newline_no_quit (prevline - 1, -1); pos = *compute_motion (prevline, 0, lmargin + (prevline == BEG ? start_hpos : 0), 0, from, /* Don't care for VPOS... */ 1 << (BITS_PER_SHORT - 1), /* ... nor HPOS. */ 1 << (BITS_PER_SHORT - 1), -1, hscroll, /* This compensates for start_hpos so that a tab as first character still occupies 8 columns. */ (prevline == BEG ? -start_hpos : 0), w); vpos -= pos.vpos; first = 0; from = prevline; } /* If we made exactly the desired vertical distance, or if we hit beginning of buffer, return point found */ if (vpos >= vtarget) { val_vmotion.bufpos = from; val_vmotion.bytepos = CHAR_TO_BYTE (from); val_vmotion.vpos = vpos; val_vmotion.hpos = lmargin; val_vmotion.contin = 0; val_vmotion.prevhpos = 0; val_vmotion.ovstring_chars_done = 0; val_vmotion.tab_offset = 0; /* For accumulating tab offset. */ return &val_vmotion; } /* Otherwise find the correct spot by moving down */ } /* Moving downward is simple, but must calculate from beg of line to determine hpos of starting point */ from_byte = CHAR_TO_BYTE (from); if (from > BEGV && FETCH_BYTE (from_byte - 1) != '\n') { Lisp_Object propval; prevline = find_next_newline_no_quit (from, -1); while (prevline > BEGV && ((selective > 0 && indented_beyond_p (prevline, CHAR_TO_BYTE (prevline), (double) selective)) /* iftc */ /* Watch out for newlines with `invisible' property. When moving downward, check the newline after. */ || (propval = Fget_char_property (make_number (prevline), Qinvisible, text_prop_object), TEXT_PROP_MEANS_INVISIBLE (propval)))) prevline = find_next_newline_no_quit (prevline - 1, -1); pos = *compute_motion (prevline, 0, lmargin + (prevline == BEG ? start_hpos : 0), 0, from, /* Don't care for VPOS... */ 1 << (BITS_PER_SHORT - 1), /* ... nor HPOS. */ 1 << (BITS_PER_SHORT - 1), -1, hscroll, (prevline == BEG ? -start_hpos : 0), w); did_motion = 1; } else { pos.hpos = lmargin + (from == BEG ? start_hpos : 0); pos.vpos = 0; pos.tab_offset = 0; did_motion = 0; } return compute_motion (from, vpos, pos.hpos, did_motion, ZV, vtarget, - (1 << (BITS_PER_SHORT - 1)), -1, hscroll, pos.tab_offset - (from == BEG ? start_hpos : 0), w); } DEFUN ("vertical-motion", Fvertical_motion, Svertical_motion, 1, 2, 0, doc: /* Move point to start of the screen line LINES lines down. If LINES is negative, this means moving up. This function is an ordinary cursor motion function which calculates the new position based on how text would be displayed. The new position may be the start of a line, or just the start of a continuation line. The function returns number of screen lines moved over; that usually equals LINES, but may be closer to zero if beginning or end of buffer was reached. The optional second argument WINDOW specifies the window to use for parameters such as width, horizontal scrolling, and so on. The default is to use the selected window's parameters. `vertical-motion' always uses the current buffer, regardless of which buffer is displayed in WINDOW. This is consistent with other cursor motion functions and makes it possible to use `vertical-motion' in any buffer, whether or not it is currently displayed in some window. */) (lines, window) Lisp_Object lines, window; { struct it it; struct text_pos pt; struct window *w; Lisp_Object old_buffer; struct gcpro gcpro1; CHECK_NUMBER (lines); if (! NILP (window)) CHECK_WINDOW (window); else window = selected_window; w = XWINDOW (window); old_buffer = Qnil; GCPRO1 (old_buffer); if (XBUFFER (w->buffer) != current_buffer) { /* Set the window's buffer temporarily to the current buffer. */ old_buffer = w->buffer; XSETBUFFER (w->buffer, current_buffer); } if (noninteractive) { struct position pos; pos = *vmotion (PT, XINT (lines), w); SET_PT_BOTH (pos.bufpos, pos.bytepos); } else { int it_start; int oselective; int it_overshoot_expected_p; SET_TEXT_POS (pt, PT, PT_BYTE); start_display (&it, w, pt); /* Scan from the start of the line containing PT. If we don't do this, we start moving with IT->current_x == 0, while PT is really at some x > 0. The effect is, in continuation lines, that we end up with the iterator placed at where it thinks X is 0, while the end position is really at some X > 0, the same X that PT had. */ it_start = IT_CHARPOS (it); /* We expect the call to move_it_to, further down, to overshoot if the starting point is on an image, stretch glyph, or Lisp string. We won't need to backtrack in this situation, except for one corner case: when the Lisp string contains a newline. */ if (it.method == GET_FROM_STRING) { const char *s = SDATA (it.string); const char *e = s + SBYTES (it.string); while (s < e && *s != '\n') ++s; it_overshoot_expected_p = (s == e); } else it_overshoot_expected_p = (it.method == GET_FROM_IMAGE || it.method == GET_FROM_STRETCH); reseat_at_previous_visible_line_start (&it); it.current_x = it.hpos = 0; /* Temporarily disable selective display so we don't move too far */ oselective = it.selective; it.selective = 0; move_it_to (&it, PT, -1, -1, -1, MOVE_TO_POS); it.selective = oselective; /* Move back if we got too far. This may happen if truncate-lines is on and PT is beyond right margin. Don't go back if the overshoot is expected (see above). */ if (IT_CHARPOS (it) > it_start && XINT (lines) > 0 && !it_overshoot_expected_p) move_it_by_lines (&it, -1, 0); it.vpos = 0; /* Do this even if LINES is 0, so that we move back to the beginning of the current line as we ought. */ if (XINT (lines) >= 0 || IT_CHARPOS (it) > 0) move_it_by_lines (&it, XINT (lines), 0); SET_PT_BOTH (IT_CHARPOS (it), IT_BYTEPOS (it)); } if (BUFFERP (old_buffer)) w->buffer = old_buffer; RETURN_UNGCPRO (make_number (it.vpos)); } /* File's initialization. */ void syms_of_indent () { DEFVAR_BOOL ("indent-tabs-mode", &indent_tabs_mode, doc: /* *Indentation can insert tabs if this is non-nil. Setting this variable automatically makes it local to the current buffer. */); indent_tabs_mode = 1; defsubr (&Scurrent_indentation); defsubr (&Sindent_to); defsubr (&Scurrent_column); defsubr (&Smove_to_column); defsubr (&Svertical_motion); defsubr (&Scompute_motion); } /* arch-tag: 9adfea44-71f7-4988-8ee3-96da15c502cc (do not change this comment) */