+From 94353eb52055927d9079f3d9e33da1c954abf386 Mon Sep 17 00:00:00 2001
+Date: Wed, 26 Jun 2019 13:25:10 +0200
+Subject: [PATCH] Add support for fuzzy-matching
+
+---
+ config.def.h | 1 +
+ config.mk | 2 +-
+ dmenu.c | 89 ++++++++++++++++++++++++++++++++++++++++++++++++++++
+ 3 files changed, 91 insertions(+), 1 deletion(-)
+
+diff --git a/config.def.h b/config.def.h
+index 1edb647..51612b9 100644
+--- a/config.def.h
++++ b/config.def.h
+@@ -2,6 +2,7 @@
+ /* Default settings; can be overriden by command line. */
+
+ static int topbar = 1; /* -b option; if 0, dmenu appears at bottom */
++static int fuzzy = 1; /* -F option; if 0, dmenu doesn't use fuzzy matching */
+ /* -fn option overrides fonts[0]; default X11 font or font set */
+ static const char *fonts[] = {
+ "monospace:size=10"
+diff --git a/config.mk b/config.mk
+index 0929b4a..d14309a 100644
+--- a/config.mk
++++ b/config.mk
+@@ -20,7 +20,7 @@ FREETYPEINC = /usr/include/freetype2
+
+ # includes and libs
+ INCS = -I$(X11INC) -I$(FREETYPEINC)
+-LIBS = -L$(X11LIB) -lX11 $(XINERAMALIBS) $(FREETYPELIBS)
++LIBS = -L$(X11LIB) -lX11 $(XINERAMALIBS) $(FREETYPELIBS) -lm
+
+ # flags
+ CPPFLAGS = -D_DEFAULT_SOURCE -D_BSD_SOURCE -D_XOPEN_SOURCE=700 -D_POSIX_C_SOURCE=200809L -DVERSION=\"$(VERSION)\" $(XINERAMAFLAGS)
+diff --git a/dmenu.c b/dmenu.c
+index 6b8f51b..96ddc98 100644
+--- a/dmenu.c
++++ b/dmenu.c
+@@ -1,6 +1,7 @@
+ /* See LICENSE file for copyright and license details. */
+ #include <ctype.h>
+ #include <locale.h>
++#include <math.h>
+ #include <stdio.h>
+ #include <stdlib.h>
+ #include <string.h>
+@@ -32,6 +33,7 @@ struct item {
+ char *text;
+ struct item *left, *right;
+ int out;
++ double distance;
+ };
+
+ static char text[BUFSIZ] = "";
+@@ -210,9 +212,94 @@ grabkeyboard(void)
+ die("cannot grab keyboard");
+ }
+
++int
++compare_distance(const void *a, const void *b)
++{
++ struct item *da = *(struct item **) a;
++ struct item *db = *(struct item **) b;
++
++ if (!db)
++ return 1;
++ if (!da)
++ return -1;
++
++ return da->distance == db->distance ? 0 : da->distance < db->distance ? -1 : 1;
++}
++
++void
++fuzzymatch(void)
++{
++ /* bang - we have so much memory */
++ struct item *it;
++ struct item **fuzzymatches = NULL;
++ char c;
++ int number_of_matches = 0, i, pidx, sidx, eidx;
++ int text_len = strlen(text), itext_len;
++
++ matches = matchend = NULL;
++
++ /* walk through all items */
++ for (it = items; it && it->text; it++) {
++ if (text_len) {
++ itext_len = strlen(it->text);
++ pidx = 0; /* pointer */
++ sidx = eidx = -1; /* start of match, end of match */
++ /* walk through item text */
++ for (i = 0; i < itext_len && (c = it->text[i]); i++) {
++ /* fuzzy match pattern */
++ if (!fstrncmp(&text[pidx], &c, 1)) {
++ if(sidx == -1)
++ sidx = i;
++ pidx++;
++ if (pidx == text_len) {
++ eidx = i;
++ break;
++ }
++ }
++ }
++ /* build list of matches */
++ if (eidx != -1) {
++ /* compute distance */
++ /* add penalty if match starts late (log(sidx+2))
++ * add penalty for long a match without many matching characters */
++ it->distance = log(sidx + 2) + (double)(eidx - sidx - text_len);
++ /* fprintf(stderr, "distance %s %f\n", it->text, it->distance); */
++ appenditem(it, &matches, &matchend);
++ number_of_matches++;
++ }
++ } else {
++ appenditem(it, &matches, &matchend);
++ }
++ }
++
++ if (number_of_matches) {
++ /* initialize array with matches */
++ if (!(fuzzymatches = realloc(fuzzymatches, number_of_matches * sizeof(struct item*))))
++ die("cannot realloc %u bytes:", number_of_matches * sizeof(struct item*));
++ for (i = 0, it = matches; it && i < number_of_matches; i++, it = it->right) {
++ fuzzymatches[i] = it;
++ }
++ /* sort matches according to distance */
++ qsort(fuzzymatches, number_of_matches, sizeof(struct item*), compare_distance);
++ /* rebuild list of matches */
++ matches = matchend = NULL;
++ for (i = 0, it = fuzzymatches[i]; i < number_of_matches && it && \
++ it->text; i++, it = fuzzymatches[i]) {
++ appenditem(it, &matches, &matchend);
++ }
++ free(fuzzymatches);
++ }
++ curr = sel = matches;
++ calcoffsets();
++}
++
+ static void
+ match(void)
+ {
++ if (fuzzy) {
++ fuzzymatch();
++ return;
++ }
+ static char **tokv = NULL;
+ static int tokn = 0;
+
+@@ -702,6 +789,8 @@ main(int argc, char *argv[])
+ topbar = 0;
+ else if (!strcmp(argv[i], "-f")) /* grabs keyboard before reading stdin */
+ fast = 1;
++ else if (!strcmp(argv[i], "-F")) /* grabs keyboard before reading stdin */
++ fuzzy = 0;
+ else if (!strcmp(argv[i], "-i")) { /* case-insensitive item matching */
+ fstrncmp = strncasecmp;
+ fstrstr = cistrstr;
+--
+2.22.0
+