2 * Copyright (C) 1984-2014 Mark Nudelman
4 * You may distribute under the terms of either the GNU General Public
5 * License or the Less License, as specified in the README file.
7 * For more information, see the README file.
12 * Routines to search a file for a pattern.
20 #define MINPOS(a,b) (((a) < (b)) ? (a) : (b))
21 #define MAXPOS(a,b) (((a) > (b)) ? (a) : (b))
24 extern int how_search;
28 extern int jump_sline;
31 extern int status_col;
32 extern void * constant ml_search;
33 extern POSITION start_attnpos;
34 extern POSITION end_attnpos;
36 extern int screen_trashed;
38 extern int hilite_search;
39 extern int size_linebuf;
41 extern int can_goto_line;
42 static int hide_hilite;
43 static POSITION prep_startpos;
44 static POSITION prep_endpos;
45 static int is_caseless;
46 static int is_ucase_pattern;
49 * Structures for maintaining a set of ranges for hilites and filtered-out
50 * lines. Each range is stored as a node within a red-black tree, and we
51 * try to extend existing ranges (without creating overlaps) rather than
52 * create new nodes if possible. We remember the last node found by a
53 * search for constant-time lookup if the next search is near enough to
54 * the previous. To aid that, we overlay a secondary doubly-linked list
55 * on top of the red-black tree so we can find the preceding/succeeding
56 * nodes also in constant time.
58 * Each node is allocated from a series of pools, each pool double the size
59 * of the previous (for amortised constant time allocation). Since our only
60 * tree operations are clear and node insertion, not node removal, we don't
61 * need to maintain a usage bitmap or freelist and can just return nodes
62 * from the pool in-order until capacity is reached.
71 struct hilite_node *parent;
72 struct hilite_node *left;
73 struct hilite_node *right;
74 struct hilite_node *prev;
75 struct hilite_node *next;
84 struct hilite_storage *next;
88 struct hilite_storage *first;
89 struct hilite_storage *current;
90 struct hilite_node *root;
92 struct hilite_node *lookaside;
94 #define HILITE_INITIALIZER() { NULL, NULL, NULL, NULL }
95 #define HILITE_LOOKASIDE_STEPS 2
97 static struct hilite_tree hilite_anchor = HILITE_INITIALIZER();
98 static struct hilite_tree filter_anchor = HILITE_INITIALIZER();
103 * These are the static variables that represent the "remembered"
104 * search pattern and filter pattern.
106 struct pattern_info {
107 DEFINE_PATTERN(compiled);
113 #define info_compiled(info) ((void*)0)
115 #define info_compiled(info) ((info)->compiled)
118 static struct pattern_info search_info;
119 static struct pattern_info filter_info;
122 * Are there any uppercase letters in this string?
128 char *str_end = str + strlen(str);
131 while (str < str_end)
133 ch = step_char(&str, +1, str_end);
141 * Compile and save a search pattern.
144 set_pattern(info, pattern, search_type)
145 struct pattern_info *info;
151 CLEAR_PATTERN(info->compiled);
152 else if (compile_pattern(pattern, search_type, &info->compiled) < 0)
155 /* Pattern compiled successfully; save the text too. */
156 if (info->text != NULL)
161 info->text = (char *) ecalloc(1, strlen(pattern)+1);
162 strcpy(info->text, pattern);
164 info->search_type = search_type;
167 * Ignore case if -I is set OR
168 * -i is set AND the pattern is all lowercase.
170 is_ucase_pattern = is_ucase(pattern);
171 if (is_ucase_pattern && caseless != OPT_ONPLUS)
174 is_caseless = caseless;
179 * Discard a saved pattern.
183 struct pattern_info *info;
185 if (info->text != NULL)
189 uncompile_pattern(&info->compiled);
194 * Initialize saved pattern to nothing.
198 struct pattern_info *info;
200 CLEAR_PATTERN(info->compiled);
202 info->search_type = 0;
206 * Initialize search variables.
211 init_pattern(&search_info);
212 init_pattern(&filter_info);
216 * Determine which text conversions to perform before pattern matching.
222 if (is_caseless || bs_mode == BS_SPECIAL)
226 if (bs_mode == BS_SPECIAL)
228 if (bs_mode != BS_CONTROL)
230 } else if (bs_mode != BS_CONTROL)
234 if (ctldisp == OPT_ONPLUS)
240 * Is there a previous (remembered) search pattern?
244 struct pattern_info *info;
247 if ((info->search_type & SRCH_NO_REGEX) == 0)
248 return (!is_null_pattern(info->compiled));
250 return (info->text != NULL);
255 * Repaint the hilites currently displayed on the screen.
256 * Repaint each line which contains highlighted text.
257 * If on==0, force all hilites off.
265 int save_hide_hilite;
270 save_hide_hilite = hide_hilite;
281 hide_hilite = save_hide_hilite;
285 for (slinenum = TOP; slinenum < TOP + sc_height-1; slinenum++)
287 pos = position(slinenum);
288 if (pos == NULL_POSITION)
290 (void) forw_line(pos);
295 hide_hilite = save_hide_hilite;
299 * Clear the attn hilite.
305 POSITION old_start_attnpos;
306 POSITION old_end_attnpos;
311 if (start_attnpos == NULL_POSITION)
313 old_start_attnpos = start_attnpos;
314 old_end_attnpos = end_attnpos;
315 start_attnpos = end_attnpos = NULL_POSITION;
325 for (slinenum = TOP; slinenum < TOP + sc_height-1; slinenum++)
327 pos = position(slinenum);
328 if (pos == NULL_POSITION)
330 epos = position(slinenum+1);
331 if (pos < old_end_attnpos &&
332 (epos == NULL_POSITION || epos > old_start_attnpos))
334 (void) forw_line(pos);
346 * Hide search string highlighting.
351 if (!prev_pattern(&search_info))
353 error("No previous regular expression", NULL_PARG);
357 hide_hilite = !hide_hilite;
364 * Clear the hilite list.
368 struct hilite_tree *anchor;
370 struct hilite_storage *hls;
371 struct hilite_storage *nexthls;
373 for (hls = anchor->first; hls != NULL; hls = nexthls)
378 anchor->first = NULL;
379 anchor->current = NULL;
382 anchor->lookaside = NULL;
384 prep_startpos = prep_endpos = NULL_POSITION;
390 clr_hlist(&hilite_anchor);
396 clr_hlist(&filter_anchor);
401 struct hilite_tree *anchor;
403 struct hilite_node *n = anchor->root;
404 while (n != NULL && n->right != NULL)
411 struct hilite_node *n;
418 struct hilite_node *n;
424 * Find the node covering pos, or the node after it if no node covers it,
425 * or return NULL if pos is after the last range. Remember the found node,
426 * to speed up subsequent searches for the same or similar positions (if
427 * we return NULL, remember the last node.)
430 hlist_find(anchor, pos)
431 struct hilite_tree *anchor;
434 struct hilite_node *n, *m;
436 if (anchor->lookaside)
441 n = anchor->lookaside;
445 if (pos < n->r.hl_endpos)
447 if (n->prev == NULL || pos >= n->prev->r.hl_endpos)
452 } else if (n->next == NULL)
460 * If we don't find the right node within a small
461 * distance, don't keep doing a linear search!
463 if (steps >= HILITE_LOOKASIDE_STEPS)
467 if (pos < n->r.hl_endpos)
468 anchor->lookaside = n = n->prev;
470 anchor->lookaside = n = n->next;
482 if (pos < n->r.hl_startpos)
492 if (pos >= n->r.hl_endpos)
494 if (n->right != NULL)
512 anchor->lookaside = n;
514 anchor->lookaside = m;
520 * Should any characters in a specified range be highlighted?
523 is_hilited_range(pos, epos)
527 struct hilite_node *n = hlist_find(&hilite_anchor, pos);
528 return (n != NULL && (epos == NULL_POSITION || epos > n->r.hl_startpos));
532 * Is a line "filtered" -- that is, should it be hidden?
538 struct hilite_node *n;
540 if (ch_getflags() & CH_HELPFILE)
543 n = hlist_find(&filter_anchor, pos);
544 return (n != NULL && pos >= n->r.hl_startpos);
548 * If pos is hidden, return the next position which isn't, otherwise
555 struct hilite_node *n;
557 if (ch_getflags() & CH_HELPFILE)
560 n = hlist_find(&filter_anchor, pos);
561 while (n != NULL && pos >= n->r.hl_startpos)
563 pos = n->r.hl_endpos;
570 * If pos is hidden, return the previous position which isn't or 0 if
571 * we're filtered right to the beginning, otherwise just return pos.
577 struct hilite_node *n;
579 if (ch_getflags() & CH_HELPFILE)
582 n = hlist_find(&filter_anchor, pos);
583 while (n != NULL && pos >= n->r.hl_startpos)
585 pos = n->r.hl_startpos;
596 * Should any characters in a specified range be highlighted?
597 * If nohide is nonzero, don't consider hide_hilite.
600 is_hilited(pos, epos, nohide, p_matches)
608 if (p_matches != NULL)
612 start_attnpos != NULL_POSITION &&
614 (epos == NULL_POSITION || epos > start_attnpos))
616 * The attn line overlaps this range.
620 match = is_hilited_range(pos, epos);
624 if (p_matches != NULL)
626 * Report matches, even if we're hiding highlights.
630 if (hilite_search == 0)
632 * Not doing highlighting.
636 if (!nohide && hide_hilite)
638 * Highlighting is hidden.
646 * Tree node storage: get the current block of nodes if it has spare
647 * capacity, or create a new one if not.
649 static struct hilite_storage*
650 hlist_getstorage(anchor)
651 struct hilite_tree *anchor;
654 int allocsize = sizeof(struct hilite_storage);
655 struct hilite_storage *s;
659 if (anchor->current->used < anchor->current->capacity)
660 return anchor->current;
661 capacity = anchor->current->capacity * 2;
663 allocsize += capacity * sizeof(struct hilite_node);
664 s = ecalloc(1, allocsize);
665 s->capacity = capacity;
669 anchor->current->next = s;
677 * Tree node storage: retrieve a new empty node to be inserted into the
680 static struct hilite_node*
681 hlist_getnode(anchor)
682 struct hilite_tree *anchor;
684 struct hilite_storage *s = hlist_getstorage(anchor);
686 struct hilite_node *n = ((struct hilite_node*)(s+1))+s->used;
692 * Rotate the tree left around a pivot node.
695 hlist_rotate_left(anchor, n)
696 struct hilite_tree *anchor;
697 struct hilite_node *n;
699 struct hilite_node *np = n->parent;
700 struct hilite_node *nr = n->right;
701 struct hilite_node *nrl = n->right->left;
723 * Rotate the tree right around a pivot node.
726 hlist_rotate_right(anchor, n)
727 struct hilite_tree *anchor;
728 struct hilite_node *n;
730 struct hilite_node *np = n->parent;
731 struct hilite_node *nl = n->left;
732 struct hilite_node *nlr = n->left->right;
755 * Add a new hilite to a hilite list.
758 add_hilite(anchor, hl)
759 struct hilite_tree *anchor;
762 struct hilite_node *p, *n, *u;
764 /* Ignore empty ranges. */
765 if (hl->hl_startpos >= hl->hl_endpos)
770 /* Inserting the very first node is trivial. */
773 n = hlist_getnode(anchor);
776 anchor->lookaside = n;
781 * Find our insertion point. If we come across any overlapping
782 * or adjoining existing ranges, shrink our range and discard
783 * if it become empty.
787 if (hl->hl_startpos < p->r.hl_startpos)
789 if (hl->hl_endpos > p->r.hl_startpos)
790 hl->hl_endpos = p->r.hl_startpos;
798 if (hl->hl_startpos < p->r.hl_endpos) {
799 hl->hl_startpos = p->r.hl_endpos;
800 if (hl->hl_startpos >= hl->hl_endpos)
803 if (p->right != NULL)
812 * Now we're at the right leaf, again check for contiguous ranges
813 * and extend the existing node if possible to avoid the
814 * insertion. Otherwise insert a new node at the leaf.
816 if (hl->hl_startpos < p->r.hl_startpos) {
817 if (hl->hl_endpos == p->r.hl_startpos)
819 p->r.hl_startpos = hl->hl_startpos;
822 if (p->prev != NULL && p->prev->r.hl_endpos == hl->hl_startpos)
824 p->prev->r.hl_endpos = hl->hl_endpos;
828 p->left = n = hlist_getnode(anchor);
837 if (p->r.hl_endpos == hl->hl_startpos)
839 p->r.hl_endpos = hl->hl_endpos;
842 if (p->next != NULL && hl->hl_endpos == p->next->r.hl_startpos) {
843 p->next->r.hl_startpos = hl->hl_startpos;
847 p->right = n = hlist_getnode(anchor);
861 * The tree is in the correct order and covers the right ranges
862 * now, but may have become unbalanced. Rebalance it using the
863 * standard red-black tree constraints and operations.
867 /* case 1 - current is root, root is always black */
868 if (n->parent == NULL)
874 /* case 2 - parent is black, we can always be red */
879 * constraint: because the root must be black, if our
880 * parent is red it cannot be the root therefore we must
885 * case 3 - parent and uncle are red, repaint them black,
886 * the grandparent red, and start again at the grandparent.
888 u = n->parent->parent->left;
890 u = n->parent->parent->right;
891 if (u != NULL && u->red)
895 n = n->parent->parent;
901 * case 4 - parent is red but uncle is black, parent and
902 * grandparent on opposite sides. We need to start
903 * changing the structure now. This and case 5 will shorten
904 * our branch and lengthen the sibling, between them
907 if (n == n->parent->right &&
908 n->parent == n->parent->parent->left)
910 hlist_rotate_left(anchor, n->parent);
912 } else if (n == n->parent->left &&
913 n->parent == n->parent->parent->right)
915 hlist_rotate_right(anchor, n->parent);
920 * case 5 - parent is red but uncle is black, parent and
921 * grandparent on same side
924 n->parent->parent->red = 1;
925 if (n == n->parent->left)
926 hlist_rotate_right(anchor, n->parent->parent);
928 hlist_rotate_left(anchor, n->parent->parent);
934 * Hilight every character in a range of displayed characters.
937 create_hilites(linepos, start_index, end_index, chpos)
946 /* Start the first hilite. */
947 hl.hl_startpos = linepos + chpos[start_index];
950 * Step through the displayed chars.
951 * If the source position (before cvt) of the char is one more
952 * than the source pos of the previous char (the usual case),
953 * just increase the size of the current hilite by one.
954 * Otherwise (there are backspaces or something involved),
955 * finish the current hilite and start a new one.
957 for (i = start_index+1; i <= end_index; i++)
959 if (chpos[i] != chpos[i-1] + 1 || i == end_index)
961 hl.hl_endpos = linepos + chpos[i-1] + 1;
962 add_hilite(&hilite_anchor, &hl);
963 /* Start new hilite unless this is the last char. */
966 hl.hl_startpos = linepos + chpos[i];
973 * Make a hilite for each string in a physical line which matches
974 * the current pattern.
975 * sp,ep delimit the first match already found.
978 hilite_line(linepos, line, line_len, chpos, sp, ep, cvt_ops)
988 char *line_end = line + line_len;
990 if (sp == NULL || ep == NULL)
993 * sp and ep delimit the first match in the line.
994 * Mark the corresponding file positions, then
995 * look for further matches and mark them.
996 * {{ This technique, of calling match_pattern on subsequent
997 * substrings of the line, may mark more than is correct
998 * if the pattern starts with "^". This bug is fixed
999 * for those regex functions that accept a notbol parameter
1000 * (currently POSIX, PCRE and V8-with-regexec2). }}
1004 create_hilites(linepos, sp-line, ep-line, chpos);
1006 * If we matched more than zero characters,
1007 * move to the first char after the string we matched.
1008 * If we matched zero, just move to the next char.
1012 else if (searchp != line_end)
1014 else /* end of line */
1016 } while (match_pattern(info_compiled(&search_info), search_info.text,
1017 searchp, line_end - searchp, &sp, &ep, 1, search_info.search_type));
1022 * Change the caseless-ness of searches.
1023 * Updates the internal search state to reflect a change in the -i flag.
1028 if (!is_ucase_pattern)
1030 * Pattern did not have uppercase.
1031 * Just set the search caselessness to the global caselessness.
1033 is_caseless = caseless;
1036 * Pattern did have uppercase.
1037 * Discard the pattern; we can't change search caselessness now.
1039 clear_pattern(&search_info);
1044 * Find matching text which is currently on screen and highlight it.
1049 struct scrpos scrpos;
1051 get_scrpos(&scrpos);
1052 if (scrpos.pos == NULL_POSITION)
1054 prep_hilite(scrpos.pos, position(BOTTOM_PLUS_ONE), -1);
1059 * Change highlighting parameters.
1065 * Erase any highlights currently on screen.
1070 if (hilite_search == OPT_ONPLUS)
1072 * Display highlights.
1079 * Figure out where to start a search.
1082 search_pos(search_type)
1091 * Start at the beginning (or end) of the file.
1092 * The empty_screen() case is mainly for
1093 * command line initiated searches;
1094 * for example, "+/xyz" on the command line.
1095 * Also for multi-file (SRCH_PAST_EOF) searches.
1097 if (search_type & SRCH_FORW)
1103 if (pos == NULL_POSITION)
1105 (void) ch_end_seek();
1114 if (how_search == OPT_ON)
1117 * Search does not include current screen.
1119 if (search_type & SRCH_FORW)
1120 linenum = BOTTOM_PLUS_ONE;
1123 } else if (how_search == OPT_ONPLUS && !(search_type & SRCH_AFTER_TARGET))
1126 * Search includes all of displayed screen.
1128 if (search_type & SRCH_FORW)
1131 linenum = BOTTOM_PLUS_ONE;
1135 * Search includes the part of current screen beyond the jump target.
1136 * It starts at the jump target (if searching backwards),
1137 * or at the jump target plus one (if forwards).
1139 linenum = jump_sline;
1140 if (search_type & SRCH_FORW)
1143 linenum = adjsline(linenum);
1144 pos = position(linenum);
1146 pos = forw_raw_line(pos, (char **)NULL, (int *)NULL);
1150 * If the line is empty, look around for a plausible starting place.
1152 if (search_type & SRCH_FORW)
1154 while (pos == NULL_POSITION)
1156 if (++linenum >= sc_height)
1158 pos = position(linenum);
1162 while (pos == NULL_POSITION)
1166 pos = position(linenum);
1173 * Search a subset of the file, specified by start/end position.
1176 search_range(pos, endpos, search_type, matches, maxlines, plinepos, pendpos)
1194 POSITION linepos, oldpos;
1196 linenum = find_linenum(pos);
1201 * Get lines until we find a matching one or until
1202 * we hit end-of-file (or beginning-of-file if we're
1203 * going backwards), or until we hit the end position.
1208 * A signal aborts the search.
1213 if ((endpos != NULL_POSITION && pos >= endpos) || maxlines == 0)
1216 * Reached end position without a match.
1218 if (pendpos != NULL)
1225 if (search_type & SRCH_FORW)
1228 * Read the next line, and save the
1229 * starting position of that line in linepos.
1232 pos = forw_raw_line(pos, &line, &line_len);
1238 * Read the previous line and save the
1239 * starting position of that line in linepos.
1241 pos = back_raw_line(pos, &line, &line_len);
1247 if (pos == NULL_POSITION)
1250 * Reached EOF/BOF without a match.
1252 if (pendpos != NULL)
1258 * If we're using line numbers, we might as well
1259 * remember the information we have now (the position
1260 * and line number of the current line).
1261 * Don't do it for every line because it slows down
1262 * the search. Remember the line number only if
1263 * we're "far" from the last place we remembered it.
1265 if (linenums && abs((int)(pos - oldpos)) > 2048)
1266 add_lnum(linenum, pos);
1269 if (is_filtered(linepos))
1273 * If it's a caseless search, convert the line to lowercase.
1274 * If we're doing backspace processing, delete backspaces.
1276 cvt_ops = get_cvt_ops();
1277 cvt_len = cvt_length(line_len, cvt_ops);
1278 cline = (char *) ecalloc(1, cvt_len);
1279 chpos = cvt_alloc_chpos(cvt_len);
1280 cvt_text(cline, line, chpos, &line_len, cvt_ops);
1284 * Check to see if the line matches the filter pattern.
1285 * If so, add an entry to the filter list.
1287 if (((search_type & SRCH_FIND_ALL) ||
1288 prep_startpos == NULL_POSITION ||
1289 linepos < prep_startpos || linepos >= prep_endpos) &&
1290 prev_pattern(&filter_info)) {
1291 int line_filter = match_pattern(info_compiled(&filter_info), filter_info.text,
1292 cline, line_len, &sp, &ep, 0, filter_info.search_type);
1296 hl.hl_startpos = linepos;
1298 add_hilite(&filter_anchor, &hl);
1305 * Test the next line to see if we have a match.
1306 * We are successful if we either want a match and got one,
1307 * or if we want a non-match and got one.
1309 if (prev_pattern(&search_info))
1311 line_match = match_pattern(info_compiled(&search_info), search_info.text,
1312 cline, line_len, &sp, &ep, 0, search_type);
1318 if (search_type & SRCH_FIND_ALL)
1322 * We are supposed to find all matches in the range.
1323 * Just add the matches in this line to the
1324 * hilite list and keep searching.
1326 hilite_line(linepos, cline, line_len, chpos, sp, ep, cvt_ops);
1328 } else if (--matches <= 0)
1331 * Found the one match we're looking for.
1335 if (hilite_search == OPT_ON)
1338 * Clear the hilite list and add only
1339 * the matches in this one line.
1342 hilite_line(linepos, cline, line_len, chpos, sp, ep, cvt_ops);
1347 if (plinepos != NULL)
1348 *plinepos = linepos;
1359 * search for a pattern in history. If found, compile that pattern.
1362 hist_pattern(search_type)
1368 set_mlist(ml_search, 0);
1369 pattern = cmd_lastpattern();
1370 if (pattern == NULL)
1373 if (set_pattern(&search_info, pattern, search_type) < 0)
1377 if (hilite_search == OPT_ONPLUS && !hide_hilite)
1382 #else /* CMD_HISTORY */
1384 #endif /* CMD_HISTORY */
1388 * Search for the n-th occurrence of a specified pattern,
1389 * either forward or backward.
1390 * Return the number of matches not yet found in this file
1391 * (that is, n minus the number of matches found).
1392 * Return -1 if the search should be aborted.
1393 * Caller may continue the search in another file
1394 * if less than n matches are found in this file.
1397 search(search_type, pattern, n)
1404 if (pattern == NULL || *pattern == '\0')
1407 * A null pattern means use the previously compiled pattern.
1409 search_type |= SRCH_AFTER_TARGET;
1410 if (!prev_pattern(&search_info) && !hist_pattern(search_type))
1412 error("No previous regular expression", NULL_PARG);
1415 if ((search_type & SRCH_NO_REGEX) !=
1416 (search_info.search_type & SRCH_NO_REGEX))
1418 error("Please re-enter search pattern", NULL_PARG);
1422 if (hilite_search == OPT_ON)
1425 * Erase the highlights currently on screen.
1426 * If the search fails, we'll redisplay them later.
1430 if (hilite_search == OPT_ONPLUS && hide_hilite)
1433 * Highlight any matches currently on screen,
1434 * before we actually start the search.
1444 * Compile the pattern.
1446 if (set_pattern(&search_info, pattern, search_type) < 0)
1452 * Erase the highlights currently on screen.
1453 * Also permanently delete them from the hilite list.
1459 if (hilite_search == OPT_ONPLUS)
1462 * Highlight any matches currently on screen,
1463 * before we actually start the search.
1471 * Figure out where to start the search.
1473 pos = search_pos(search_type);
1474 if (pos == NULL_POSITION)
1477 * Can't find anyplace to start searching from.
1479 if (search_type & SRCH_PAST_EOF)
1481 /* repaint(); -- why was this here? */
1482 error("Nothing to search", NULL_PARG);
1486 n = search_range(pos, NULL_POSITION, search_type, n, -1,
1487 &pos, (POSITION*)NULL);
1491 * Search was unsuccessful.
1494 if (hilite_search == OPT_ON && n > 0)
1496 * Redisplay old hilites.
1503 if (!(search_type & SRCH_NO_MOVE))
1506 * Go to the matching line.
1508 jump_loc(pos, jump_sline);
1512 if (hilite_search == OPT_ON)
1514 * Display new hilites in the matching line.
1524 * Prepare hilites in a given range of the file.
1526 * The pair (prep_startpos,prep_endpos) delimits a contiguous region
1527 * of the file that has been "prepared"; that is, scanned for matches for
1528 * the current search pattern, and hilites have been created for such matches.
1529 * If prep_startpos == NULL_POSITION, the prep region is empty.
1530 * If prep_endpos == NULL_POSITION, the prep region extends to EOF.
1531 * prep_hilite asks that the range (spos,epos) be covered by the prep region.
1534 prep_hilite(spos, epos, maxlines)
1539 POSITION nprep_startpos = prep_startpos;
1540 POSITION nprep_endpos = prep_endpos;
1547 * Search beyond where we're asked to search, so the prep region covers
1548 * more than we need. Do one big search instead of a bunch of small ones.
1550 #define SEARCH_MORE (3*size_linebuf)
1552 if (!prev_pattern(&search_info) && !is_filtering())
1556 * Make sure our prep region always starts at the beginning of
1557 * a line. (search_range takes care of the end boundary below.)
1559 spos = back_raw_line(spos+1, (char **)NULL, (int *)NULL);
1562 * If we're limited to a max number of lines, figure out the
1563 * file position we should stop at.
1566 max_epos = NULL_POSITION;
1570 for (i = 0; i < maxlines; i++)
1571 max_epos = forw_raw_line(max_epos, (char **)NULL, (int *)NULL);
1576 * The range that we need to search (spos,epos); and the range that
1577 * the "prep" region will then cover (nprep_startpos,nprep_endpos).
1580 if (prep_startpos == NULL_POSITION ||
1581 (epos != NULL_POSITION && epos < prep_startpos) ||
1585 * New range is not contiguous with old prep region.
1586 * Discard the old prep region and start a new one.
1590 if (epos != NULL_POSITION)
1591 epos += SEARCH_MORE;
1592 nprep_startpos = spos;
1596 * New range partially or completely overlaps old prep region.
1598 if (epos == NULL_POSITION)
1601 * New range goes to end of file.
1604 } else if (epos > prep_endpos)
1607 * New range ends after old prep region.
1608 * Extend prep region to end at end of new range.
1610 epos += SEARCH_MORE;
1611 } else /* (epos <= prep_endpos) */
1614 * New range ends within old prep region.
1615 * Truncate search to end at start of old prep region.
1617 epos = prep_startpos;
1620 if (spos < prep_startpos)
1623 * New range starts before old prep region.
1624 * Extend old prep region backwards to start at
1625 * start of new range.
1627 if (spos < SEARCH_MORE)
1630 spos -= SEARCH_MORE;
1631 nprep_startpos = spos;
1632 } else /* (spos >= prep_startpos) */
1635 * New range starts within or after old prep region.
1636 * Trim search to start at end of old prep region.
1642 if (epos != NULL_POSITION && max_epos != NULL_POSITION &&
1645 * Don't go past the max position we're allowed.
1649 if (epos == NULL_POSITION || epos > spos)
1651 int search_type = SRCH_FORW | SRCH_FIND_ALL;
1652 search_type |= (search_info.search_type & SRCH_NO_REGEX);
1655 result = search_range(spos, epos, search_type, 0, maxlines, (POSITION*)NULL, &new_epos);
1658 if (prep_endpos == NULL_POSITION || new_epos > prep_endpos)
1659 nprep_endpos = new_epos;
1662 * Check both ends of the resulting prep region to
1663 * make sure they're not filtered. If they are,
1664 * keep going at least one more line until we find
1665 * something that isn't filtered, or hit the end.
1667 if (prep_endpos == NULL_POSITION || nprep_endpos > prep_endpos)
1669 if (new_epos >= nprep_endpos && is_filtered(new_epos-1))
1671 spos = nprep_endpos;
1672 epos = forw_raw_line(nprep_endpos, (char **)NULL, (int *)NULL);
1673 if (epos == NULL_POSITION)
1680 if (prep_startpos == NULL_POSITION || nprep_startpos < prep_startpos)
1682 if (nprep_startpos > 0 && is_filtered(nprep_startpos))
1684 epos = nprep_startpos;
1685 spos = back_raw_line(nprep_startpos, (char **)NULL, (int *)NULL);
1686 if (spos == NULL_POSITION)
1688 nprep_startpos = spos;
1696 prep_startpos = nprep_startpos;
1697 prep_endpos = nprep_endpos;
1701 * Set the pattern to be used for line filtering.
1704 set_filter_pattern(pattern, search_type)
1709 if (pattern == NULL || *pattern == '\0')
1710 clear_pattern(&filter_info);
1712 set_pattern(&filter_info, pattern, search_type);
1717 * Is there a line filter in effect?
1722 if (ch_getflags() & CH_HELPFILE)
1724 return prev_pattern(&filter_info);
1730 * This function is called by the V8 regcomp to report
1731 * errors in regular expressions.
1733 public int reg_show_error = 1;
1741 if (!reg_show_error)