1/* $Id: search.c,v 1.197.2.1 2007/04/19 03:15:04 dolorous Exp $ */
2/**************************************************************************
3 *   search.c                                                             *
4 *                                                                        *
5 *   Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004 Chris Allegretta    *
6 *   Copyright (C) 2005, 2006, 2007 David Lawrence Ramsey                 *
7 *   This program 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)  *
10 *   any later version.                                                   *
11 *                                                                        *
12 *   This program is distributed in the hope that it will be useful, but  *
13 *   WITHOUT ANY WARRANTY; without even the implied warranty of           *
14 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU    *
15 *   General Public License for more details.                             *
16 *                                                                        *
17 *   You should have received a copy of the GNU General Public License    *
18 *   along with this program; if not, write to the Free Software          *
19 *   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA            *
20 *   02110-1301, USA.                                                     *
21 *                                                                        *
22 **************************************************************************/
23
24#include "proto.h"
25
26#include <string.h>
27#include <stdio.h>
28#include <unistd.h>
29#include <ctype.h>
30#include <errno.h>
31
32static bool search_last_line = FALSE;
33	/* Have we gone past the last line while searching? */
34#if !defined(NANO_TINY) && defined(ENABLE_NANORC)
35static bool history_changed = FALSE;
36	/* Have any of the history lists changed? */
37#endif
38#ifdef HAVE_REGEX_H
39static bool regexp_compiled = FALSE;
40	/* Have we compiled any regular expressions? */
41
42/* Compile the regular expression regexp to see if it's valid.  Return
43 * TRUE if it is, or FALSE otherwise. */
44bool regexp_init(const char *regexp)
45{
46    int rc;
47
48    assert(!regexp_compiled);
49
50    rc = regcomp(&search_regexp, regexp, REG_EXTENDED
51#ifndef NANO_TINY
52	| (ISSET(CASE_SENSITIVE) ? 0 : REG_ICASE)
53#endif
54	);
55
56    if (rc != 0) {
57	size_t len = regerror(rc, &search_regexp, NULL, 0);
58	char *str = charalloc(len);
59
60	regerror(rc, &search_regexp, str, len);
61	statusbar(_("Bad regex \"%s\": %s"), regexp, str);
62	free(str);
63
64	return FALSE;
65    }
66
67    regexp_compiled = TRUE;
68
69    return TRUE;
70}
71
72/* Decompile the compiled regular expression we used in the last
73 * search, if any. */
74void regexp_cleanup(void)
75{
76    if (regexp_compiled) {
77	regexp_compiled = FALSE;
78	regfree(&search_regexp);
79    }
80}
81#endif
82
83/* Indicate on the statusbar that the string at str was not found by the
84 * last search. */
85void not_found_msg(const char *str)
86{
87    char *disp;
88    int numchars;
89
90    assert(str != NULL);
91
92    disp = display_string(str, 0, (COLS / 2) + 1, FALSE);
93    numchars = actual_x(disp, mbstrnlen(disp, COLS / 2));
94
95    statusbar(_("\"%.*s%s\" not found"), numchars, disp,
96	(disp[numchars] == '\0') ? "" : "...");
97
98    free(disp);
99}
100
101/* Abort the current search or replace.  Clean up by displaying the main
102 * shortcut list, updating the screen if the mark was on before, and
103 * decompiling the compiled regular expression we used in the last
104 * search, if any. */
105void search_replace_abort(void)
106{
107    display_main_list();
108#ifndef NANO_TINY
109    if (openfile->mark_set)
110	edit_refresh();
111#endif
112#ifdef HAVE_REGEX_H
113    regexp_cleanup();
114#endif
115}
116
117/* Initialize the global search and replace strings. */
118void search_init_globals(void)
119{
120    if (last_search == NULL)
121	last_search = mallocstrcpy(NULL, "");
122    if (last_replace == NULL)
123	last_replace = mallocstrcpy(NULL, "");
124}
125
126/* Set up the system variables for a search or replace.  If use_answer
127 * is TRUE, only set backupstring to answer.  Return -2 to run the
128 * opposite program (search -> replace, replace -> search), return -1 if
129 * the search should be canceled (due to Cancel, a blank search string,
130 * Go to Line, or a failed regcomp()), return 0 on success, and return 1
131 * on rerun calling program.
132 *
133 * replacing is TRUE if we call from do_replace(), and FALSE if called
134 * from do_search(). */
135int search_init(bool replacing, bool use_answer)
136{
137    int i = 0;
138    char *buf;
139    static char *backupstring = NULL;
140	/* The search string we'll be using. */
141
142    /* If backupstring doesn't exist, initialize it to "". */
143    if (backupstring == NULL)
144	backupstring = mallocstrcpy(NULL, "");
145
146    /* If use_answer is TRUE, set backupstring to answer and get out. */
147    if (use_answer) {
148	backupstring = mallocstrcpy(backupstring, answer);
149	return 0;
150    }
151
152    /* We display the search prompt below.  If the user types a partial
153     * search string and then Replace or a toggle, we will return to
154     * do_search() or do_replace() and be called again.  In that case,
155     * we should put the same search string back up. */
156
157    search_init_globals();
158
159    if (last_search[0] != '\0') {
160	char *disp = display_string(last_search, 0, COLS / 3, FALSE);
161
162	buf = charalloc(strlen(disp) + 7);
163	/* We use (COLS / 3) here because we need to see more on the
164	 * line. */
165	sprintf(buf, " [%s%s]", disp,
166		(strlenpt(last_search) > COLS / 3) ? "..." : "");
167	free(disp);
168    } else
169	buf = mallocstrcpy(NULL, "");
170
171    /* This is now one simple call.  It just does a lot. */
172    i = do_prompt(FALSE,
173#ifndef DISABLE_TABCOMP
174	TRUE,
175#endif
176	replacing ? replace_list : whereis_list, backupstring,
177#ifndef NANO_TINY
178	&search_history,
179#endif
180	edit_refresh, "%s%s%s%s%s%s", _("Search"),
181#ifndef NANO_TINY
182	/* TRANSLATORS: This string is just a modifier for the search
183	 * prompt; no grammar is implied. */
184	ISSET(CASE_SENSITIVE) ? _(" [Case Sensitive]") :
185#endif
186	"",
187#ifdef HAVE_REGEX_H
188	/* TRANSLATORS: This string is just a modifier for the search
189	 * prompt; no grammar is implied. */
190	ISSET(USE_REGEXP) ? _(" [Regexp]") :
191#endif
192	"",
193#ifndef NANO_TINY
194	/* TRANSLATORS: This string is just a modifier for the search
195	 * prompt; no grammar is implied. */
196	ISSET(BACKWARDS_SEARCH) ? _(" [Backwards]") :
197#endif
198	"", replacing ?
199#ifndef NANO_TINY
200	openfile->mark_set ? _(" (to replace) in selection") :
201#endif
202	_(" (to replace)") : "", buf);
203
204    /* Release buf now that we don't need it anymore. */
205    free(buf);
206
207    free(backupstring);
208    backupstring = NULL;
209
210    /* Cancel any search, or just return with no previous search. */
211    if (i == -1 || (i < 0 && last_search[0] == '\0') ||
212	    (!replacing && i == 0 && answer[0] == '\0')) {
213	statusbar(_("Cancelled"));
214	return -1;
215    } else {
216	switch (i) {
217	    case -2:		/* It's an empty string. */
218	    case 0:		/* It's a new string. */
219#ifdef HAVE_REGEX_H
220		/* Use last_search if answer is an empty string, or
221		 * answer if it isn't. */
222		if (ISSET(USE_REGEXP) && !regexp_init((i == -2) ?
223			last_search : answer))
224		    return -1;
225#endif
226		break;
227#ifndef NANO_TINY
228	    case TOGGLE_CASE_KEY:
229		TOGGLE(CASE_SENSITIVE);
230		backupstring = mallocstrcpy(backupstring, answer);
231		return 1;
232	    case TOGGLE_BACKWARDS_KEY:
233		TOGGLE(BACKWARDS_SEARCH);
234		backupstring = mallocstrcpy(backupstring, answer);
235		return 1;
236#endif
237#ifdef HAVE_REGEX_H
238	    case NANO_REGEXP_KEY:
239		TOGGLE(USE_REGEXP);
240		backupstring = mallocstrcpy(backupstring, answer);
241		return 1;
242#endif
243	    case NANO_TOOTHERSEARCH_KEY:
244		backupstring = mallocstrcpy(backupstring, answer);
245		return -2;	/* Call the opposite search function. */
246	    case NANO_TOGOTOLINE_KEY:
247		do_gotolinecolumn(openfile->current->lineno,
248			openfile->placewewant + 1, TRUE, TRUE, FALSE,
249			TRUE);
250				/* Put answer up on the statusbar and
251				 * fall through. */
252	    default:
253		return -1;
254	}
255    }
256
257    return 0;
258}
259
260/* Look for needle, starting at (current, current_x).  If no_sameline is
261 * TRUE, skip over begin when looking for needle.  begin is the line
262 * where we first started searching, at column begin_x.  The return
263 * value specifies whether we found anything.  If we did, set needle_len
264 * to the length of the string we found if it isn't NULL. */
265bool findnextstr(
266#ifndef DISABLE_SPELLER
267	bool whole_word,
268#endif
269	bool no_sameline, const filestruct *begin, size_t begin_x, const
270	char *needle, size_t *needle_len)
271{
272    size_t found_len;
273	/* The length of the match we find. */
274    size_t current_x_find = 0;
275	/* The location in the current line of the match we find. */
276    ssize_t current_y_find = openfile->current_y;
277    filestruct *fileptr = openfile->current;
278    const char *rev_start = fileptr->data, *found = NULL;
279
280    /* rev_start might end up 1 character before the start or after the
281     * end of the line.  This won't be a problem because strstrwrapper()
282     * will return immediately and say that no match was found, and
283     * rev_start will be properly set when the search continues on the
284     * previous or next line. */
285    rev_start +=
286#ifndef NANO_TINY
287	ISSET(BACKWARDS_SEARCH) ?
288	openfile->current_x - 1 :
289#endif
290	openfile->current_x + 1;
291
292    /* Look for needle in the current line we're searching. */
293    while (TRUE) {
294	found = strstrwrapper(fileptr->data, needle, rev_start);
295
296	/* We've found a potential match. */
297	if (found != NULL) {
298#ifndef DISABLE_SPELLER
299	    bool found_whole = FALSE;
300		/* Is this potential match a whole word? */
301#endif
302
303	    /* Set found_len to the length of the potential match. */
304	    found_len =
305#ifdef HAVE_REGEX_H
306		ISSET(USE_REGEXP) ?
307		regmatches[0].rm_eo - regmatches[0].rm_so :
308#endif
309		strlen(needle);
310
311#ifndef DISABLE_SPELLER
312	    /* If we're searching for whole words, see if this potential
313	     * match is a whole word. */
314	    if (whole_word) {
315		char *word = mallocstrncpy(NULL, found, found_len + 1);
316		word[found_len] = '\0';
317
318		found_whole = is_whole_word(found - fileptr->data,
319			fileptr->data, word);
320		free(word);
321	    }
322#endif
323
324	    /* If we're searching for whole words and this potential
325	     * match isn't a whole word, or if we're not allowed to find
326	     * a match on the same line we started on and this potential
327	     * match is on that line, continue searching. */
328	    if (
329#ifndef DISABLE_SPELLER
330		(!whole_word || found_whole) &&
331#endif
332		(!no_sameline || fileptr != openfile->current))
333		break;
334	}
335
336	/* We've finished processing the file, so get out. */
337	if (search_last_line) {
338	    not_found_msg(needle);
339	    return FALSE;
340	}
341
342	/* Move to the previous or next line in the file. */
343#ifndef NANO_TINY
344	if (ISSET(BACKWARDS_SEARCH)) {
345	    fileptr = fileptr->prev;
346	    current_y_find--;
347	} else {
348#endif
349	    fileptr = fileptr->next;
350	    current_y_find++;
351#ifndef NANO_TINY
352	}
353#endif
354
355	/* We've reached the start or end of the buffer, so wrap
356	 * around. */
357	if (fileptr == NULL) {
358#ifndef NANO_TINY
359	    if (ISSET(BACKWARDS_SEARCH)) {
360		fileptr = openfile->filebot;
361		current_y_find = editwinrows - 1;
362	    } else {
363#endif
364		fileptr = openfile->fileage;
365		current_y_find = 0;
366#ifndef NANO_TINY
367	    }
368#endif
369	    statusbar(_("Search Wrapped"));
370	}
371
372	/* We've reached the original starting line. */
373	if (fileptr == begin)
374	    search_last_line = TRUE;
375
376	rev_start = fileptr->data;
377#ifndef NANO_TINY
378	if (ISSET(BACKWARDS_SEARCH))
379	    rev_start += strlen(fileptr->data);
380#endif
381    }
382
383    /* We found an instance. */
384    current_x_find = found - fileptr->data;
385
386    /* Ensure we haven't wrapped around again! */
387    if (search_last_line &&
388#ifndef NANO_TINY
389	((!ISSET(BACKWARDS_SEARCH) && current_x_find > begin_x) ||
390	(ISSET(BACKWARDS_SEARCH) && current_x_find < begin_x))
391#else
392	current_x_find > begin_x
393#endif
394	) {
395	not_found_msg(needle);
396	return FALSE;
397    }
398
399    /* We've definitely found something. */
400    openfile->current = fileptr;
401    openfile->current_x = current_x_find;
402    openfile->placewewant = xplustabs();
403    openfile->current_y = current_y_find;
404
405    /* needle_len holds the length of needle. */
406    if (needle_len != NULL)
407	*needle_len = found_len;
408
409    return TRUE;
410}
411
412/* Clear the flag indicating that a search reached the last line of the
413 * file.  We need to do this just before a new search. */
414void findnextstr_wrap_reset(void)
415{
416    search_last_line = FALSE;
417}
418
419/* Search for a string. */
420void do_search(void)
421{
422    filestruct *fileptr = openfile->current;
423    size_t fileptr_x = openfile->current_x;
424    size_t pww_save = openfile->placewewant;
425    int i;
426    bool didfind;
427
428    i = search_init(FALSE, FALSE);
429
430    if (i == -1)
431	/* Cancel, Go to Line, blank search string, or regcomp()
432	 * failed. */
433	search_replace_abort();
434    else if (i == -2)
435	/* Replace. */
436	do_replace();
437#if !defined(NANO_TINY) || defined(HAVE_REGEX_H)
438    else if (i == 1)
439	/* Case Sensitive, Backwards, or Regexp search toggle. */
440	do_search();
441#endif
442
443    if (i != 0)
444	return;
445
446    /* If answer is now "", copy last_search into answer. */
447    if (answer[0] == '\0')
448	answer = mallocstrcpy(answer, last_search);
449    else
450	last_search = mallocstrcpy(last_search, answer);
451
452#ifndef NANO_TINY
453    /* If answer is not "", add this search string to the search history
454     * list. */
455    if (answer[0] != '\0')
456	update_history(&search_history, answer);
457#endif
458
459    findnextstr_wrap_reset();
460    didfind = findnextstr(
461#ifndef DISABLE_SPELLER
462	FALSE,
463#endif
464	FALSE, openfile->current, openfile->current_x, answer, NULL);
465
466    /* Check to see if there's only one occurrence of the string and
467     * we're on it now. */
468    if (fileptr == openfile->current && fileptr_x ==
469	openfile->current_x && didfind) {
470#ifdef HAVE_REGEX_H
471	/* Do the search again, skipping over the current line, if we're
472	 * doing a bol and/or eol regex search ("^", "$", or "^$"), so
473	 * that we find one only once per line.  We should only end up
474	 * back at the same position if the string isn't found again, in
475	 * which case it's the only occurrence. */
476	if (ISSET(USE_REGEXP) && regexp_bol_or_eol(&search_regexp,
477		last_search)) {
478	    didfind = findnextstr(
479#ifndef DISABLE_SPELLER
480		FALSE,
481#endif
482		TRUE, openfile->current,
483		openfile->current_x, answer, NULL);
484	    if (fileptr == openfile->current && fileptr_x ==
485		openfile->current_x && !didfind)
486		statusbar(_("This is the only occurrence"));
487	} else {
488#endif
489	    statusbar(_("This is the only occurrence"));
490#ifdef HAVE_REGEX_H
491	}
492#endif
493    }
494
495    openfile->placewewant = xplustabs();
496    edit_redraw(fileptr, pww_save);
497    search_replace_abort();
498}
499
500#ifndef NANO_TINY
501/* Search for the last string without prompting. */
502void do_research(void)
503{
504    filestruct *fileptr = openfile->current;
505    size_t fileptr_x = openfile->current_x;
506    size_t pww_save = openfile->placewewant;
507    bool didfind;
508
509    search_init_globals();
510
511    if (last_search[0] != '\0') {
512#ifdef HAVE_REGEX_H
513	/* Since answer is "", use last_search! */
514	if (ISSET(USE_REGEXP) && !regexp_init(last_search))
515	    return;
516#endif
517
518	findnextstr_wrap_reset();
519	didfind = findnextstr(
520#ifndef DISABLE_SPELLER
521		FALSE,
522#endif
523		FALSE, openfile->current, openfile->current_x,
524		last_search, NULL);
525
526	/* Check to see if there's only one occurrence of the string and
527	 * we're on it now. */
528	if (fileptr == openfile->current && fileptr_x ==
529		openfile->current_x && didfind) {
530#ifdef HAVE_REGEX_H
531	    /* Do the search again, skipping over the current line, if
532	     * we're doing a bol and/or eol regex search ("^", "$", or
533	     * "^$"), so that we find one only once per line.  We should
534	     * only end up back at the same position if the string isn't
535	     * found again, in which case it's the only occurrence. */
536	    if (ISSET(USE_REGEXP) && regexp_bol_or_eol(&search_regexp,
537		last_search)) {
538		didfind = findnextstr(
539#ifndef DISABLE_SPELLER
540			FALSE,
541#endif
542			TRUE, openfile->current, openfile->current_x,
543			answer, NULL);
544		if (fileptr == openfile->current && fileptr_x ==
545			openfile->current_x && !didfind)
546		    statusbar(_("This is the only occurrence"));
547	    } else {
548#endif
549		statusbar(_("This is the only occurrence"));
550#ifdef HAVE_REGEX_H
551	    }
552#endif
553	}
554    } else
555        statusbar(_("No current search pattern"));
556
557    openfile->placewewant = xplustabs();
558    edit_redraw(fileptr, pww_save);
559    search_replace_abort();
560}
561#endif
562
563#ifdef HAVE_REGEX_H
564int replace_regexp(char *string, bool create)
565{
566    /* We have a split personality here.  If create is FALSE, just
567     * calculate the size of the replacement line (necessary because of
568     * subexpressions \1 to \9 in the replaced text). */
569
570    const char *c = last_replace;
571    size_t search_match_count = regmatches[0].rm_eo -
572	regmatches[0].rm_so;
573    size_t new_line_size = strlen(openfile->current->data) + 1 -
574	search_match_count;
575
576    /* Iterate through the replacement text to handle subexpression
577     * replacement using \1, \2, \3, etc. */
578    while (*c != '\0') {
579	int num = (*(c + 1) - '0');
580
581	if (*c != '\\' || num < 1 || num > 9 || num >
582		search_regexp.re_nsub) {
583	    if (create)
584		*string++ = *c;
585	    c++;
586	    new_line_size++;
587	} else {
588	    size_t i = regmatches[num].rm_eo - regmatches[num].rm_so;
589
590	    /* Skip over the replacement expression. */
591	    c += 2;
592
593	    /* But add the length of the subexpression to new_size. */
594	    new_line_size += i;
595
596	    /* And if create is TRUE, append the result of the
597	     * subexpression match to the new line. */
598	    if (create) {
599		strncpy(string, openfile->current->data +
600			openfile->current_x + regmatches[num].rm_so, i);
601		string += i;
602	    }
603	}
604    }
605
606    if (create)
607	*string = '\0';
608
609    return new_line_size;
610}
611#endif
612
613char *replace_line(const char *needle)
614{
615    char *copy;
616    size_t new_line_size, search_match_count;
617
618    /* Calculate the size of the new line. */
619#ifdef HAVE_REGEX_H
620    if (ISSET(USE_REGEXP)) {
621	search_match_count = regmatches[0].rm_eo - regmatches[0].rm_so;
622	new_line_size = replace_regexp(NULL, FALSE);
623    } else {
624#endif
625	search_match_count = strlen(needle);
626	new_line_size = strlen(openfile->current->data) -
627		search_match_count + strlen(answer) + 1;
628#ifdef HAVE_REGEX_H
629    }
630#endif
631
632    /* Create the buffer. */
633    copy = charalloc(new_line_size);
634
635    /* The head of the original line. */
636    strncpy(copy, openfile->current->data, openfile->current_x);
637
638    /* The replacement text. */
639#ifdef HAVE_REGEX_H
640    if (ISSET(USE_REGEXP))
641	replace_regexp(copy + openfile->current_x, TRUE);
642    else
643#endif
644	strcpy(copy + openfile->current_x, answer);
645
646    /* The tail of the original line. */
647    assert(openfile->current_x + search_match_count <= strlen(openfile->current->data));
648
649    strcat(copy, openfile->current->data + openfile->current_x +
650	search_match_count);
651
652    return copy;
653}
654
655/* Step through each replace word and prompt user before replacing.
656 * Parameters real_current and real_current_x are needed in order to
657 * allow the cursor position to be updated when a word before the cursor
658 * is replaced by a shorter word.
659 *
660 * needle is the string to seek.  We replace it with answer.  Return -1
661 * if needle isn't found, else the number of replacements performed.  If
662 * canceled isn't NULL, set it to TRUE if we canceled. */
663ssize_t do_replace_loop(
664#ifndef DISABLE_SPELLER
665	bool whole_word,
666#endif
667	bool *canceled, const filestruct *real_current, size_t
668	*real_current_x, const char *needle)
669{
670    ssize_t numreplaced = -1;
671    size_t match_len;
672    bool replaceall = FALSE;
673#ifdef HAVE_REGEX_H
674    /* The starting-line match and bol/eol regex flags. */
675    bool begin_line = FALSE, bol_or_eol = FALSE;
676#endif
677#ifndef NANO_TINY
678    bool old_mark_set = openfile->mark_set;
679    filestruct *edittop_save = openfile->edittop, *top, *bot;
680    size_t top_x, bot_x;
681    bool right_side_up = FALSE;
682	/* TRUE if (mark_begin, mark_begin_x) is the top of the mark,
683	 * FALSE if (current, current_x) is. */
684
685    if (old_mark_set) {
686	/* If the mark is on, partition the filestruct so that it
687	 * contains only the marked text, set edittop to the top of the
688	 * partition, turn the mark off, and refresh the screen. */
689	mark_order((const filestruct **)&top, &top_x,
690	    (const filestruct **)&bot, &bot_x, &right_side_up);
691	filepart = partition_filestruct(top, top_x, bot, bot_x);
692	openfile->edittop = openfile->fileage;
693	openfile->mark_set = FALSE;
694	edit_refresh();
695    }
696#endif
697
698    if (canceled != NULL)
699	*canceled = FALSE;
700
701    findnextstr_wrap_reset();
702    while (findnextstr(
703#ifndef DISABLE_SPELLER
704	whole_word,
705#endif
706#ifdef HAVE_REGEX_H
707	/* We should find a bol and/or eol regex only once per line.  If
708	 * the bol_or_eol flag is set, it means that the last search
709	 * found one on the beginning line, so we should skip over the
710	 * beginning line when doing this search. */
711	bol_or_eol
712#else
713	FALSE
714#endif
715	, real_current, *real_current_x, needle, &match_len)) {
716	int i = 0;
717
718#ifdef HAVE_REGEX_H
719	/* If the bol_or_eol flag is set, we've found a match on the
720	 * beginning line already, and we're still on the beginning line
721	 * after the search, it means that we've wrapped around, so
722	 * we're done. */
723	if (bol_or_eol && begin_line && openfile->current ==
724		real_current)
725	    break;
726	/* Otherwise, set the begin_line flag if we've found a match on
727	 * the beginning line, reset the bol_or_eol flag, and
728	 * continue. */
729	else {
730	    if (openfile->current == real_current)
731		begin_line = TRUE;
732	    bol_or_eol = FALSE;
733	}
734#endif
735
736	if (!replaceall)
737	    edit_refresh();
738
739	/* Indicate that we found the search string. */
740	if (numreplaced == -1)
741	    numreplaced = 0;
742
743	if (!replaceall) {
744	    size_t xpt = xplustabs();
745	    char *exp_word = display_string(openfile->current->data,
746		xpt, strnlenpt(openfile->current->data,
747		openfile->current_x + match_len) - xpt, FALSE);
748
749	    curs_set(0);
750
751	    do_replace_highlight(TRUE, exp_word);
752
753	    i = do_yesno_prompt(TRUE, _("Replace this instance?"));
754
755	    do_replace_highlight(FALSE, exp_word);
756
757	    free(exp_word);
758
759	    curs_set(1);
760
761	    if (i == -1) {	/* We canceled the replace. */
762		if (canceled != NULL)
763		    *canceled = TRUE;
764		break;
765	    }
766	}
767
768#ifdef HAVE_REGEX_H
769	/* Set the bol_or_eol flag if we're doing a bol and/or eol regex
770	 * replace ("^", "$", or "^$"). */
771	if (ISSET(USE_REGEXP) && regexp_bol_or_eol(&search_regexp,
772		needle))
773	    bol_or_eol = TRUE;
774#endif
775
776	if (i > 0 || replaceall) {	/* Yes, replace it!!!! */
777	    char *copy;
778	    size_t length_change;
779
780	    if (i == 2)
781		replaceall = TRUE;
782
783	    copy = replace_line(needle);
784
785	    length_change = strlen(copy) -
786		strlen(openfile->current->data);
787
788#ifndef NANO_TINY
789	    /* If the mark was on and (mark_begin, mark_begin_x) was the
790	     * top of it, don't change mark_begin_x. */
791	    if (!old_mark_set || !right_side_up) {
792		/* Keep mark_begin_x in sync with the text changes. */
793		if (openfile->current == openfile->mark_begin &&
794			openfile->mark_begin_x > openfile->current_x) {
795		    if (openfile->mark_begin_x < openfile->current_x +
796			match_len)
797			openfile->mark_begin_x = openfile->current_x;
798		    else
799			openfile->mark_begin_x += length_change;
800		}
801	    }
802
803	    /* If the mark was on and (current, current_x) was the top
804	     * of it, don't change real_current_x. */
805	    if (!old_mark_set || right_side_up) {
806#endif
807		/* Keep real_current_x in sync with the text changes. */
808		if (openfile->current == real_current &&
809			openfile->current_x <= *real_current_x) {
810		    if (*real_current_x <
811			openfile->current_x + match_len)
812			*real_current_x = openfile->current_x +
813				match_len;
814		    *real_current_x += length_change;
815		}
816#ifndef NANO_TINY
817	    }
818#endif
819
820	    /* Set the cursor at the last character of the replacement
821	     * text, so searching will resume after the replacement
822	     * text.  Note that current_x might be set to (size_t)-1
823	     * here. */
824#ifndef NANO_TINY
825	    if (!ISSET(BACKWARDS_SEARCH))
826#endif
827		openfile->current_x += match_len + length_change - 1;
828
829	    /* Cleanup. */
830	    openfile->totsize += length_change;
831	    free(openfile->current->data);
832	    openfile->current->data = copy;
833
834	    if (!replaceall) {
835#ifdef ENABLE_COLOR
836		/* If color syntaxes are available and turned on, we
837		 * need to call edit_refresh(). */
838		if (openfile->colorstrings != NULL &&
839			!ISSET(NO_COLOR_SYNTAX))
840		    edit_refresh();
841		else
842#endif
843		    update_line(openfile->current, openfile->current_x);
844	    }
845
846	    set_modified();
847	    numreplaced++;
848	}
849    }
850
851#ifndef NANO_TINY
852    if (old_mark_set) {
853	/* If the mark was on, unpartition the filestruct so that it
854	 * contains all the text again, set edittop back to what it was
855	 * before, turn the mark back on, and refresh the screen. */
856	unpartition_filestruct(&filepart);
857	openfile->edittop = edittop_save;
858	openfile->mark_set = TRUE;
859	edit_refresh();
860    }
861#endif
862
863    /* If the NO_NEWLINES flag isn't set, and text has been added to the
864     * magicline, make a new magicline. */
865    if (!ISSET(NO_NEWLINES) && openfile->filebot->data[0] != '\0')
866	new_magicline();
867
868    return numreplaced;
869}
870
871/* Replace a string. */
872void do_replace(void)
873{
874    filestruct *edittop_save, *begin;
875    size_t begin_x, pww_save;
876    ssize_t numreplaced;
877    int i;
878
879    if (ISSET(VIEW_MODE)) {
880	print_view_warning();
881	search_replace_abort();
882	return;
883    }
884
885    i = search_init(TRUE, FALSE);
886    if (i == -1) {
887	/* Cancel, Go to Line, blank search string, or regcomp()
888	 * failed. */
889	search_replace_abort();
890	return;
891    } else if (i == -2) {
892	/* No Replace. */
893	do_search();
894	return;
895    } else if (i == 1)
896	/* Case Sensitive, Backwards, or Regexp search toggle. */
897	do_replace();
898
899    if (i != 0)
900	return;
901
902    /* If answer is not "", add answer to the search history list and
903     * copy answer into last_search. */
904    if (answer[0] != '\0') {
905#ifndef NANO_TINY
906	update_history(&search_history, answer);
907#endif
908	last_search = mallocstrcpy(last_search, answer);
909    }
910
911    last_replace = mallocstrcpy(last_replace, "");
912
913    i = do_prompt(FALSE,
914#ifndef DISABLE_TABCOMP
915	TRUE,
916#endif
917	replace_list_2, last_replace,
918#ifndef NANO_TINY
919	&replace_history,
920#endif
921	edit_refresh, _("Replace with"));
922
923#ifndef NANO_TINY
924    /* Add this replace string to the replace history list.  i == 0
925     * means that the string is not "". */
926    if (i == 0)
927	update_history(&replace_history, answer);
928#endif
929
930    if (i != 0 && i != -2) {
931	if (i == -1) {		/* Cancel. */
932	    if (last_replace[0] != '\0')
933		answer = mallocstrcpy(answer, last_replace);
934	    statusbar(_("Cancelled"));
935	}
936	search_replace_abort();
937	return;
938    }
939
940    last_replace = mallocstrcpy(last_replace, answer);
941
942    /* Save where we are. */
943    edittop_save = openfile->edittop;
944    begin = openfile->current;
945    begin_x = openfile->current_x;
946    pww_save = openfile->placewewant;
947
948    numreplaced = do_replace_loop(
949#ifndef DISABLE_SPELLER
950	FALSE,
951#endif
952	NULL, begin, &begin_x, last_search);
953
954    /* Restore where we were. */
955    openfile->edittop = edittop_save;
956    openfile->current = begin;
957    openfile->current_x = begin_x;
958    openfile->placewewant = pww_save;
959
960    edit_refresh();
961
962    if (numreplaced >= 0)
963	statusbar(P_("Replaced %lu occurrence",
964		"Replaced %lu occurrences", (unsigned long)numreplaced),
965		(unsigned long)numreplaced);
966
967    search_replace_abort();
968}
969
970/* Go to the specified line and column, or ask for them if interactive
971 * is TRUE.  Save the x-coordinate and y-coordinate if save_pos is TRUE.
972 * Update the screen afterwards if allow_update is TRUE.  Note that both
973 * the line and column numbers should be one-based. */
974void do_gotolinecolumn(ssize_t line, ssize_t column, bool use_answer,
975	bool interactive, bool save_pos, bool allow_update)
976{
977    if (interactive) {
978	char *ans = mallocstrcpy(NULL, answer);
979
980	/* Ask for the line and column. */
981	int i = do_prompt(FALSE,
982#ifndef DISABLE_TABCOMP
983		TRUE,
984#endif
985		gotoline_list, use_answer ? ans : "",
986#ifndef NANO_TINY
987		NULL,
988#endif
989		edit_refresh, _("Enter line number, column number"));
990
991	free(ans);
992
993	/* Cancel, or Enter with blank string. */
994	if (i < 0) {
995	    statusbar(_("Cancelled"));
996	    display_main_list();
997	    return;
998	}
999
1000	if (i == NANO_TOOTHERWHEREIS_KEY) {
1001	    /* Keep answer up on the statusbar. */
1002	    search_init(TRUE, TRUE);
1003
1004	    do_search();
1005	    return;
1006	}
1007
1008	/* Do a bounds check.  Display a warning on an out-of-bounds
1009	 * line or column number only if we hit Enter at the statusbar
1010	 * prompt. */
1011	if (!parse_line_column(answer, &line, &column) || line < 1 ||
1012		column < 1) {
1013	    if (i == 0)
1014		statusbar(_("Come on, be reasonable"));
1015	    display_main_list();
1016	    return;
1017	}
1018    } else {
1019	if (line < 1)
1020	    line = openfile->current->lineno;
1021
1022	if (column < 1)
1023	    column = openfile->placewewant + 1;
1024    }
1025
1026    for (openfile->current = openfile->fileage;
1027	openfile->current != openfile->filebot && line > 1; line--)
1028	openfile->current = openfile->current->next;
1029
1030    openfile->current_x = actual_x(openfile->current->data, column - 1);
1031    openfile->placewewant = column - 1;
1032
1033    /* Put the top line of the edit window in range of the current line.
1034     * If save_pos is TRUE, don't change the cursor position when doing
1035     * it. */
1036    edit_update(save_pos ? NONE : CENTER);
1037
1038    /* If allow_update is TRUE, update the screen. */
1039    if (allow_update)
1040	edit_refresh();
1041
1042    display_main_list();
1043}
1044
1045/* Go to the specified line and column, asking for them beforehand. */
1046void do_gotolinecolumn_void(void)
1047{
1048    do_gotolinecolumn(openfile->current->lineno,
1049	openfile->placewewant + 1, FALSE, TRUE, FALSE, TRUE);
1050}
1051
1052#ifndef DISABLE_SPELLER
1053/* Go to the line with the number specified in pos_line, the
1054 * x-coordinate specified in pos_x, the y-coordinate specified in pos_y,
1055 * and the place we want specified in pos_pww. */
1056void do_gotopos(ssize_t pos_line, size_t pos_x, ssize_t pos_y, size_t
1057	pos_pww)
1058{
1059    /* Since do_gotolinecolumn() resets the x-coordinate but not the
1060     * y-coordinate, set the coordinates up this way. */
1061    openfile->current_y = pos_y;
1062    do_gotolinecolumn(pos_line, pos_x + 1, FALSE, FALSE, TRUE, TRUE);
1063
1064    /* Set the rest of the coordinates up. */
1065    openfile->placewewant = pos_pww;
1066    update_line(openfile->current, pos_x);
1067}
1068#endif
1069
1070#ifndef NANO_TINY
1071/* Search for a match to one of the two characters in bracket_set.  If
1072 * reverse is TRUE, search backwards for the leftmost bracket.
1073 * Otherwise, search forwards for the rightmost bracket.  Return TRUE if
1074 * we found a match, and FALSE otherwise. */
1075bool find_bracket_match(bool reverse, const char *bracket_set)
1076{
1077    filestruct *fileptr = openfile->current;
1078    const char *rev_start = NULL, *found = NULL;
1079    ssize_t current_y_find = openfile->current_y;
1080
1081    assert(mbstrlen(bracket_set) == 2);
1082
1083    /* rev_start might end up 1 character before the start or after the
1084     * end of the line.  This won't be a problem because we'll skip over
1085     * it below in that case, and rev_start will be properly set when
1086     * the search continues on the previous or next line. */
1087    rev_start = reverse ? fileptr->data + (openfile->current_x - 1) :
1088	fileptr->data + (openfile->current_x + 1);
1089
1090    /* Look for either of the two characters in bracket_set.  rev_start
1091     * can be 1 character before the start or after the end of the line.
1092     * In either case, just act as though no match is found. */
1093    while (TRUE) {
1094	found = ((rev_start > fileptr->data && *(rev_start - 1) ==
1095		'\0') || rev_start < fileptr->data) ? NULL : (reverse ?
1096		mbrevstrpbrk(fileptr->data, bracket_set, rev_start) :
1097		mbstrpbrk(rev_start, bracket_set));
1098
1099	/* We've found a potential match. */
1100	if (found != NULL)
1101	    break;
1102
1103	if (reverse) {
1104	    fileptr = fileptr->prev;
1105	    current_y_find--;
1106	} else {
1107	    fileptr = fileptr->next;
1108	    current_y_find++;
1109	}
1110
1111	/* We've reached the start or end of the buffer, so get out. */
1112	if (fileptr == NULL)
1113	    return FALSE;
1114
1115	rev_start = fileptr->data;
1116	if (reverse)
1117	    rev_start += strlen(fileptr->data);
1118    }
1119
1120    /* We've definitely found something. */
1121    openfile->current = fileptr;
1122    openfile->current_x = found - fileptr->data;
1123    openfile->placewewant = xplustabs();
1124    openfile->current_y = current_y_find;
1125
1126    return TRUE;
1127}
1128
1129/* Search for a match to the bracket at the current cursor position, if
1130 * there is one. */
1131void do_find_bracket(void)
1132{
1133    filestruct *current_save;
1134    size_t current_x_save, pww_save;
1135    const char *ch;
1136	/* The location in matchbrackets of the bracket at the current
1137	 * cursor position. */
1138    int ch_len;
1139	/* The length of ch in bytes. */
1140    const char *wanted_ch;
1141	/* The location in matchbrackets of the bracket complementing
1142	 * the bracket at the current cursor position. */
1143    int wanted_ch_len;
1144	/* The length of wanted_ch in bytes. */
1145    char *bracket_set;
1146	/* The pair of characters in ch and wanted_ch. */
1147    size_t i;
1148	/* Generic loop variable. */
1149    size_t matchhalf;
1150	/* The number of single-byte characters in one half of
1151	 * matchbrackets. */
1152    size_t mbmatchhalf;
1153	/* The number of multibyte characters in one half of
1154	 * matchbrackets. */
1155    size_t count = 1;
1156	/* The initial bracket count. */
1157    bool reverse;
1158	/* The direction we search. */
1159    char *found_ch;
1160	/* The character we find. */
1161
1162    assert(mbstrlen(matchbrackets) % 2 == 0);
1163
1164    ch = openfile->current->data + openfile->current_x;
1165
1166    if (ch == '\0' || (ch = mbstrchr(matchbrackets, ch)) == NULL) {
1167	statusbar(_("Not a bracket"));
1168	return;
1169    }
1170
1171    /* Save where we are. */
1172    current_save = openfile->current;
1173    current_x_save = openfile->current_x;
1174    pww_save = openfile->placewewant;
1175
1176    /* If we're on an opening bracket, which must be in the first half
1177     * of matchbrackets, we want to search forwards for a closing
1178     * bracket.  If we're on a closing bracket, which must be in the
1179     * second half of matchbrackets, we want to search backwards for an
1180     * opening bracket. */
1181    matchhalf = 0;
1182    mbmatchhalf = mbstrlen(matchbrackets) / 2;
1183
1184    for (i = 0; i < mbmatchhalf; i++)
1185	matchhalf += parse_mbchar(matchbrackets + matchhalf, NULL,
1186		NULL);
1187
1188    reverse = ((ch - matchbrackets) >= matchhalf);
1189
1190    /* If we're on an opening bracket, set wanted_ch to the character
1191     * that's matchhalf characters after ch.  If we're on a closing
1192     * bracket, set wanted_ch to the character that's matchhalf
1193     * characters before ch. */
1194    wanted_ch = ch;
1195
1196    while (mbmatchhalf > 0) {
1197	if (reverse)
1198	    wanted_ch = matchbrackets + move_mbleft(matchbrackets,
1199		wanted_ch - matchbrackets);
1200	else
1201	    wanted_ch += move_mbright(wanted_ch, 0);
1202
1203	mbmatchhalf--;
1204    }
1205
1206    ch_len = parse_mbchar(ch, NULL, NULL);
1207    wanted_ch_len = parse_mbchar(wanted_ch, NULL, NULL);
1208
1209    /* Fill bracket_set in with the values of ch and wanted_ch. */
1210    bracket_set = charalloc((mb_cur_max() * 2) + 1);
1211    strncpy(bracket_set, ch, ch_len);
1212    strncpy(bracket_set + ch_len, wanted_ch, wanted_ch_len);
1213    null_at(&bracket_set, ch_len + wanted_ch_len);
1214
1215    found_ch = charalloc(mb_cur_max() + 1);
1216
1217    while (TRUE) {
1218	if (find_bracket_match(reverse, bracket_set)) {
1219	    /* If we found an identical bracket, increment count.  If we
1220	     * found a complementary bracket, decrement it. */
1221	    parse_mbchar(openfile->current->data + openfile->current_x,
1222		found_ch, NULL);
1223	    count += (strncmp(found_ch, ch, ch_len) == 0) ? 1 : -1;
1224
1225	    /* If count is zero, we've found a matching bracket.  Update
1226	     * the screen and get out. */
1227	    if (count == 0) {
1228		edit_redraw(current_save, pww_save);
1229		break;
1230	    }
1231	} else {
1232	    /* We didn't find either an opening or closing bracket.
1233	     * Indicate this, restore where we were, and get out. */
1234	    statusbar(_("No matching bracket"));
1235	    openfile->current = current_save;
1236	    openfile->current_x = current_x_save;
1237	    openfile->placewewant = pww_save;
1238	    break;
1239	}
1240    }
1241
1242    /* Clean up. */
1243    free(bracket_set);
1244    free(found_ch);
1245}
1246
1247#ifdef ENABLE_NANORC
1248/* Indicate whether any of the history lists have changed. */
1249bool history_has_changed(void)
1250{
1251    return history_changed;
1252}
1253#endif
1254
1255/* Initialize the search and replace history lists. */
1256void history_init(void)
1257{
1258    search_history = make_new_node(NULL);
1259    search_history->data = mallocstrcpy(NULL, "");
1260    searchage = search_history;
1261    searchbot = search_history;
1262
1263    replace_history = make_new_node(NULL);
1264    replace_history->data = mallocstrcpy(NULL, "");
1265    replaceage = replace_history;
1266    replacebot = replace_history;
1267}
1268
1269/* Set the current position in the history list h to the bottom. */
1270void history_reset(const filestruct *h)
1271{
1272    if (h == search_history)
1273	search_history = searchbot;
1274    else if (h == replace_history)
1275	replace_history = replacebot;
1276}
1277
1278/* Return the first node containing the first len characters of the
1279 * string s in the history list, starting at h_start and ending at
1280 * h_end, or NULL if there isn't one. */
1281filestruct *find_history(const filestruct *h_start, const filestruct
1282	*h_end, const char *s, size_t len)
1283{
1284    const filestruct *p;
1285
1286    for (p = h_start; p != h_end->next && p != NULL; p = p->next) {
1287	if (strncmp(s, p->data, len) == 0)
1288	    return (filestruct *)p;
1289    }
1290
1291    return NULL;
1292}
1293
1294/* Update a history list.  h should be the current position in the
1295 * list. */
1296void update_history(filestruct **h, const char *s)
1297{
1298    filestruct **hage = NULL, **hbot = NULL, *p;
1299
1300    assert(h != NULL && s != NULL);
1301
1302    if (*h == search_history) {
1303	hage = &searchage;
1304	hbot = &searchbot;
1305    } else if (*h == replace_history) {
1306	hage = &replaceage;
1307	hbot = &replacebot;
1308    }
1309
1310    assert(hage != NULL && hbot != NULL);
1311
1312    /* If this string is already in the history, delete it. */
1313    p = find_history(*hage, *hbot, s, (size_t)-1);
1314
1315    if (p != NULL) {
1316	filestruct *foo, *bar;
1317
1318	/* If the string is at the beginning, move the beginning down to
1319	 * the next string. */
1320	if (p == *hage)
1321	    *hage = (*hage)->next;
1322
1323	/* Delete the string. */
1324	foo = p;
1325	bar = p->next;
1326	unlink_node(foo);
1327	delete_node(foo);
1328	if (bar != NULL)
1329	    renumber(bar);
1330    }
1331
1332    /* If the history is full, delete the beginning entry to make room
1333     * for the new entry at the end.  We assume that MAX_SEARCH_HISTORY
1334     * is greater than zero. */
1335    if ((*hbot)->lineno == MAX_SEARCH_HISTORY + 1) {
1336	filestruct *foo = *hage;
1337
1338	*hage = (*hage)->next;
1339	unlink_node(foo);
1340	delete_node(foo);
1341	renumber(*hage);
1342    }
1343
1344    /* Add the new entry to the end. */
1345    (*hbot)->data = mallocstrcpy((*hbot)->data, s);
1346    splice_node(*hbot, make_new_node(*hbot), (*hbot)->next);
1347    *hbot = (*hbot)->next;
1348    (*hbot)->data = mallocstrcpy(NULL, "");
1349
1350#ifdef ENABLE_NANORC
1351    /* Indicate that the history's been changed. */
1352    history_changed = TRUE;
1353#endif
1354
1355    /* Set the current position in the list to the bottom. */
1356    *h = *hbot;
1357}
1358
1359/* Move h to the string in the history list just before it, and return
1360 * that string.  If there isn't one, don't move h and return NULL. */
1361char *get_history_older(filestruct **h)
1362{
1363    assert(h != NULL);
1364
1365    if ((*h)->prev == NULL)
1366	return NULL;
1367
1368    *h = (*h)->prev;
1369
1370    return (*h)->data;
1371}
1372
1373/* Move h to the string in the history list just after it, and return
1374 * that string.  If there isn't one, don't move h and return NULL. */
1375char *get_history_newer(filestruct **h)
1376{
1377    assert(h != NULL);
1378
1379    if ((*h)->next == NULL)
1380	return NULL;
1381
1382    *h = (*h)->next;
1383
1384    return (*h)->data;
1385}
1386
1387#ifndef DISABLE_TABCOMP
1388/* Move h to the next string that's a tab completion of the string s,
1389 * looking at only the first len characters of s, and return that
1390 * string.  If there isn't one, or if len is 0, don't move h and return
1391 * s. */
1392char *get_history_completion(filestruct **h, const char *s, size_t len)
1393{
1394    assert(s != NULL);
1395
1396    if (len > 0) {
1397	filestruct *hage = NULL, *hbot = NULL, *p;
1398
1399	assert(h != NULL);
1400
1401	if (*h == search_history) {
1402	    hage = searchage;
1403	    hbot = searchbot;
1404	} else if (*h == replace_history) {
1405	    hage = replaceage;
1406	    hbot = replacebot;
1407	}
1408
1409	assert(hage != NULL && hbot != NULL);
1410
1411	/* Search the history list from the current position to the
1412	 * bottom for a match of len characters.  Skip over an exact
1413	 * match. */
1414	p = find_history((*h)->next, hbot, s, len);
1415
1416	while (p != NULL && strcmp(p->data, s) == 0)
1417	    p = find_history(p->next, hbot, s, len);
1418
1419	if (p != NULL) {
1420	    *h = p;
1421	    return (*h)->data;
1422	}
1423
1424	/* Search the history list from the top to the current position
1425	 * for a match of len characters.  Skip over an exact match. */
1426	p = find_history(hage, *h, s, len);
1427
1428	while (p != NULL && strcmp(p->data, s) == 0)
1429	    p = find_history(p->next, *h, s, len);
1430
1431	if (p != NULL) {
1432	    *h = p;
1433	    return (*h)->data;
1434	}
1435    }
1436
1437    /* If we're here, we didn't find a match, we didn't find an inexact
1438     * match, or len is 0.  Return s. */
1439    return (char *)s;
1440}
1441#endif /* !DISABLE_TABCOMP */
1442#endif /* !NANO_TINY */
1443