patch 8.0.0643: when a pattern search is slow Vim becomes unusable

Problem:    When 'hlsearch' is set and matching with the last search pattern
            is very slow, Vim becomes unusable.  Cannot quit search by
            pressing CTRL-C.
Solution:   When the search times out set a flag and don't try again.  Check
            for timeout and CTRL-C in NFA loop that adds states.

Author: brammool

src/edit.c

@@ -4512,7 +4512,7 @@ ins_compl_get_exp(pos_T *ini)
 		    found_new_match = searchit(NULL, ins_buf, pos,
 							      compl_direction,
 				 compl_pattern, 1L, SEARCH_KEEP + SEARCH_NFMSG,
-						  RE_LAST, (linenr_T)0, NULL);
+					     RE_LAST, (linenr_T)0, NULL, NULL);
 		--msg_silent;
 		if (!compl_started || set_match_pos)
 		{

src/evalfunc.c

@@ -9281,7 +9281,7 @@ search_cmn(typval_T *argvars, pos_T *match_pos, int *flagsp)
 
     pos = save_cursor = curwin->w_cursor;
     subpatnum = searchit(curwin, curbuf, &pos, dir, pat, 1L,
-				options, RE_SEARCH, (linenr_T)lnum_stop, &tm);
+			   options, RE_SEARCH, (linenr_T)lnum_stop, &tm, NULL);
     if (subpatnum != FAIL)
     {
 	if (flags & SP_SUBPAT)
@@ -9619,7 +9619,7 @@ do_searchpair(
     for (;;)
     {
 	n = searchit(curwin, curbuf, &pos, dir, pat, 1L,
-					   options, RE_SEARCH, lnum_stop, &tm);
+				     options, RE_SEARCH, lnum_stop, &tm, NULL);
 	if (n == FAIL || (firstpos.lnum != 0 && EQUAL_POS(pos, firstpos)))
 	    /* didn't find it or found the first match again: FAIL */
 	    break;

src/ex_cmds.c

@@ -5096,7 +5096,7 @@ do_sub(exarg_T *eap)
 		); ++lnum)
     {
 	nmatch = vim_regexec_multi(&regmatch, curwin, curbuf, lnum,
-							    (colnr_T)0, NULL);
+						       (colnr_T)0, NULL, NULL);
 	if (nmatch)
 	{
 	    colnr_T	copycol;
@@ -5695,7 +5695,7 @@ do_sub(exarg_T *eap)
 			|| nmatch_tl > 0
 			|| (nmatch = vim_regexec_multi(&regmatch, curwin,
 							curbuf, sub_firstlnum,
-							 matchcol, NULL)) == 0
+						    matchcol, NULL, NULL)) == 0
 			|| regmatch.startpos[0].lnum > 0)
 		{
 		    if (new_start != NULL)
@@ -5760,7 +5760,7 @@ do_sub(exarg_T *eap)
 		    }
 		    if (nmatch == -1 && !lastone)
 			nmatch = vim_regexec_multi(&regmatch, curwin, curbuf,
-					       sub_firstlnum, matchcol, NULL);
+					  sub_firstlnum, matchcol, NULL, NULL);
 
 		    /*
 		     * 5. break if there isn't another match in this line
@@ -6012,7 +6012,7 @@ ex_global(exarg_T *eap)
     {
 	lnum = curwin->w_cursor.lnum;
 	match = vim_regexec_multi(&regmatch, curwin, curbuf, lnum,
-							     (colnr_T)0, NULL);
+						       (colnr_T)0, NULL, NULL);
 	if ((type == 'g' && match) || (type == 'v' && !match))
 	    global_exe_one(cmd, lnum);
     }
@@ -6025,7 +6025,7 @@ ex_global(exarg_T *eap)
 	{
 	    /* a match on this line? */
 	    match = vim_regexec_multi(&regmatch, curwin, curbuf, lnum,
-							     (colnr_T)0, NULL);
+						       (colnr_T)0, NULL, NULL);
 	    if ((type == 'g' && match) || (type == 'v' && !match))
 	    {
 		ml_setmarked(lnum);

src/ex_docmd.c

@@ -4556,7 +4556,7 @@ get_address(
 			curwin->w_cursor.col = 0;
 		    searchcmdlen = 0;
 		    if (!do_search(NULL, c, cmd, 1L,
-				       SEARCH_HIS | SEARCH_MSG, NULL))
+					  SEARCH_HIS | SEARCH_MSG, NULL, NULL))
 		    {
 			curwin->w_cursor = pos;
 			cmd = NULL;
@@ -4613,7 +4613,7 @@ get_address(
 		    if (searchit(curwin, curbuf, &pos,
 				*cmd == '?' ? BACKWARD : FORWARD,
 				(char_u *)"", 1L, SEARCH_MSG,
-					i, (linenr_T)0, NULL) != FAIL)
+					i, (linenr_T)0, NULL, NULL) != FAIL)
 			lnum = pos.lnum;
 		    else
 		    {

src/ex_getln.c

@@ -1693,7 +1693,7 @@ getcmdline(
 		    i = searchit(curwin, curbuf, &t,
 				 c == Ctrl_G ? FORWARD : BACKWARD,
 				 ccline.cmdbuff, count, search_flags,
-				 RE_SEARCH, 0, NULL);
+				 RE_SEARCH, 0, NULL, NULL);
 		    --emsg_off;
 		    if (i)
 		    {
@@ -1903,9 +1903,9 @@ getcmdline(
 		i = do_search(NULL, firstc, ccline.cmdbuff, count,
 			SEARCH_KEEP + SEARCH_OPT + SEARCH_NOOF + SEARCH_PEEK,
 #ifdef FEAT_RELTIME
-			&tm
+			&tm, NULL
 #else
-			NULL
+			NULL, NULL
 #endif
 			);
 		--emsg_off;

src/gui.c

@@ -5361,7 +5361,7 @@ gui_do_findrepl(
 	    searchflags += SEARCH_START;
 	i = msg_scroll;
 	(void)do_search(NULL, down ? '/' : '?', ga.ga_data, 1L,
-							   searchflags, NULL);
+						      searchflags, NULL, NULL);
 	msg_scroll = i;	    /* don't let an error message set msg_scroll */
     }
 

src/normal.c

@@ -4358,7 +4358,7 @@ find_decl(
     {
 	valid = FALSE;
 	t = searchit(curwin, curbuf, &curwin->w_cursor, FORWARD,
-			    pat, 1L, searchflags, RE_LAST, (linenr_T)0, NULL);
+		       pat, 1L, searchflags, RE_LAST, (linenr_T)0, NULL, NULL);
 	if (curwin->w_cursor.lnum >= old_pos.lnum)
 	    t = FAIL;	/* match after start is failure too */
 
@@ -6380,7 +6380,7 @@ normal_search(
     curwin->w_set_curswant = TRUE;
 
     i = do_search(cap->oap, dir, pat, cap->count1,
-			   opt | SEARCH_OPT | SEARCH_ECHO | SEARCH_MSG, NULL);
+		      opt | SEARCH_OPT | SEARCH_ECHO | SEARCH_MSG, NULL, NULL);
     if (i == 0)
 	clearop(cap->oap);
     else

src/proto/regexp.pro

@@ -16,5 +16,5 @@ void vim_regfree(regprog_T *prog);
 int vim_regexec_prog(regprog_T **prog, int ignore_case, char_u *line, colnr_T col);
 int vim_regexec(regmatch_T *rmp, char_u *line, colnr_T col);
 int vim_regexec_nl(regmatch_T *rmp, char_u *line, colnr_T col);
-long vim_regexec_multi(regmmatch_T *rmp, win_T *win, buf_T *buf, linenr_T lnum, colnr_T col, proftime_T *tm);
+long vim_regexec_multi(regmmatch_T *rmp, win_T *win, buf_T *buf, linenr_T lnum, colnr_T col, proftime_T *tm, int *timed_out);
 /* vim: set ft=c : */

src/proto/search.pro

@@ -19,9 +19,9 @@ char_u *last_search_pat(void);
 void reset_search_dir(void);
 void set_last_search_pat(char_u *s, int idx, int magic, int setlast);
 void last_pat_prog(regmmatch_T *regmatch);
-int searchit(win_T *win, buf_T *buf, pos_T *pos, int dir, char_u *pat, long count, int options, int pat_use, linenr_T stop_lnum, proftime_T *tm);
+int searchit(win_T *win, buf_T *buf, pos_T *pos, int dir, char_u *pat, long count, int options, int pat_use, linenr_T stop_lnum, proftime_T *tm, int *timed_out);
 void set_search_direction(int cdir);
-int do_search(oparg_T *oap, int dirc, char_u *pat, long count, int options, proftime_T *tm);
+int do_search(oparg_T *oap, int dirc, char_u *pat, long count, int options, proftime_T *tm, int *timed_out);
 int search_for_exact_line(buf_T *buf, pos_T *pos, int dir, char_u *pat);
 int searchc(cmdarg_T *cap, int t_cmd);
 pos_T *findmatch(oparg_T *oap, int initc);

src/quickfix.c

@@ -2415,7 +2415,7 @@ qf_jump(
 	    save_cursor = curwin->w_cursor;
 	    curwin->w_cursor.lnum = 0;
 	    if (!do_search(NULL, '/', qf_ptr->qf_pattern, (long)1,
-							   SEARCH_KEEP, NULL))
+						      SEARCH_KEEP, NULL, NULL))
 		curwin->w_cursor = save_cursor;
 	}
 
@@ -4237,7 +4237,7 @@ ex_vimgrep(exarg_T *eap)
 	    {
 		col = 0;
 		while (vim_regexec_multi(&regmatch, curwin, buf, lnum,
-							       col, NULL) > 0)
+							  col, NULL, NULL) > 0)
 		{
 		    /* Pass the buffer number so that it gets used even for a
 		     * dummy buffer, unless duplicate_name is set, then the