From 7b2ee699f5e5759ac034765d82cbe9ebab65f30a Mon Sep 17 00:00:00 2001
From: Steve Ward <planet36@gmail.com>
Date: Fri, 15 May 2020 22:50:00 -0400
Subject: [PATCH] Enable blinking cursor

Adapted from this patch
https://lists.suckless.org/hackers/1708/15376.html

Idea to inhibit blinking cursor during drawing inspired by this patch
https://lists.suckless.org/hackers/2005/17339.html

Rename cursorshape to cursorstyle
---
 config.def.h | 15 ++++++++++-----
 x.c          | 23 ++++++++++++++++++++---
 2 files changed, 30 insertions(+), 8 deletions(-)

diff --git a/config.def.h b/config.def.h
index fdbacfd..f404201 100644
--- a/config.def.h
+++ b/config.def.h
@@ -129,13 +129,18 @@ static unsigned int defaultcs = 256;
 static unsigned int defaultrcs = 257;
 
 /*
- * Default shape of cursor
- * 2: Block ("█")
- * 4: Underline ("_")
- * 6: Bar ("|")
+ * https://invisible-island.net/xterm/ctlseqs/ctlseqs.html#h4-Functions-using-CSI-_-ordered-by-the-final-character-lparen-s-rparen:CSI-Ps-SP-q.1D81
+ * Default style of cursor
+ * 0: blinking block
+ * 1: blinking block (default)
+ * 2: steady block ("█")
+ * 3: blinking underline
+ * 4: steady underline ("_")
+ * 5: blinking bar
+ * 6: steady bar ("|")
  * 7: Snowman ("☃")
  */
-static unsigned int cursorshape = 2;
+static unsigned int cursorstyle = 1;
 
 /*
  * Default columns and rows numbers
diff --git a/x.c b/x.c
index 1dc44d6..bf280fe 100644
--- a/x.c
+++ b/x.c
@@ -1528,13 +1528,20 @@ xdrawcursor(int cx, int cy, Glyph g, int ox, int oy, Glyph og)
 		switch (win.cursor) {
 		case 7: /* st extension: snowman (U+2603) */
 			g.u = 0x2603;
-			/* FALLTHROUGH */
+			xdrawglyph(g, cx, cy);
+			break;
 		case 0: /* Blinking Block */
 		case 1: /* Blinking Block (Default) */
+			if (IS_SET(MODE_BLINK))
+				break;
+			/* FALLTHROUGH */
 		case 2: /* Steady Block */
 			xdrawglyph(g, cx, cy);
 			break;
 		case 3: /* Blinking Underline */
+			if (IS_SET(MODE_BLINK))
+				break;
+			/* FALLTHROUGH */
 		case 4: /* Steady Underline */
 			XftDrawRect(xw.draw, &drawcol,
 					borderpx + cx * win.cw,
@@ -1543,6 +1550,9 @@ xdrawcursor(int cx, int cy, Glyph g, int ox, int oy, Glyph og)
 					win.cw, cursorthickness);
 			break;
 		case 5: /* Blinking bar */
+			if (IS_SET(MODE_BLINK))
+				break;
+			/* FALLTHROUGH */
 		case 6: /* Steady bar */
 			XftDrawRect(xw.draw, &drawcol,
 					borderpx + cx * win.cw,
@@ -1871,6 +1881,7 @@ run(void)
 	int xfd = XConnectionNumber(xw.dpy), ttyfd, xev, drawing;
 	struct timespec seltv, *tv, now, lastblink, trigger;
 	double timeout;
+	int blinkcursor;
 
 	/* Waiting for window mapping */
 	do {
@@ -1937,6 +1948,10 @@ run(void)
 		if (FD_ISSET(ttyfd, &rfd) || xev) {
 			if (!drawing) {
 				trigger = now;
+				if (IS_SET(MODE_BLINK)) {
+					win.mode ^= MODE_BLINK;
+				}
+				lastblink = now;
 				drawing = 1;
 			}
 			timeout = (maxlatency - TIMEDIFF(now, trigger)) \
@@ -1947,7 +1962,9 @@ run(void)
 
 		/* idle detected or maxlatency exhausted -> draw */
 		timeout = -1;
-		if (blinktimeout && tattrset(ATTR_BLINK)) {
+		blinkcursor = win.cursor == 0 || win.cursor == 1 ||
+		              win.cursor == 3 || win.cursor == 5;
+		if (blinktimeout && (blinkcursor || tattrset(ATTR_BLINK))) {
 			timeout = blinktimeout - TIMEDIFF(now, lastblink);
 			if (timeout <= 0) {
 				if (-timeout > blinktimeout) /* start visible */
@@ -1983,7 +2000,7 @@ main(int argc, char *argv[])
 {
 	xw.l = xw.t = 0;
 	xw.isfixed = False;
-	win.cursor = cursorshape;
+	win.cursor = cursorstyle;
 
 	ARGBEGIN {
 	case 'a':
-- 
2.20.1