From a3cdd0753bf578cd4e6db7c6507481f3b5c38aea Mon Sep 17 00:00:00 2001
From: Steve Ward <planet36@gmail.com>
Date: Tue, 16 Nov 2021 14:15:06 -0500
Subject: [PATCH] Allow blinking cursor

---
 config.def.h | 19 +++++++++++++------
 x.c          | 47 +++++++++++++++++++++++++++++++++++------------
 2 files changed, 48 insertions(+), 18 deletions(-)

diff --git a/config.def.h b/config.def.h
index 6f05dce..1a5fed0 100644
--- a/config.def.h
+++ b/config.def.h
@@ -133,13 +133,20 @@ static unsigned int defaultcs = 256;
 static unsigned int defaultrcs = 257;
 
 /*
- * Default shape of cursor
- * 2: Block ("█")
- * 4: Underline ("_")
- * 6: Bar ("|")
- * 7: Snowman ("☃")
+ * 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: blinking st cursor
+ * 8: steady st cursor
  */
-static unsigned int cursorshape = 2;
+static unsigned int cursorstyle = 1;
+static Rune stcursor = 0x2603; /* snowman ("☃") */
 
 /*
  * Default columns and rows numbers
diff --git a/x.c b/x.c
index 89786b8..7d2447d 100644
--- a/x.c
+++ b/x.c
@@ -253,6 +253,7 @@ static char *opt_name  = NULL;
 static char *opt_title = NULL;
 
 static int oldbutton = 3; /* button event on startup: 3 = release */
+static int cursorblinks = 0;
 
 void
 clipcopy(const Arg *dummy)
@@ -1529,29 +1530,44 @@ xdrawcursor(int cx, int cy, Glyph g, int ox, int oy, Glyph og)
 	/* draw the new one */
 	if (IS_SET(MODE_FOCUSED)) {
 		switch (win.cursor) {
-		case 7: /* st extension */
-			g.u = 0x2603; /* snowman (U+2603) */
+		default:
+		case 0: /* blinking block */
+		case 1: /* blinking block (default) */
+			if (IS_SET(MODE_BLINK))
+				break;
 			/* FALLTHROUGH */
-		case 0: /* Blinking Block */
-		case 1: /* Blinking Block (Default) */
-		case 2: /* Steady Block */
+		case 2: /* steady block */
 			xdrawglyph(g, cx, cy);
 			break;
-		case 3: /* Blinking Underline */
-		case 4: /* Steady Underline */
+		case 3: /* blinking underline */
+			if (IS_SET(MODE_BLINK))
+				break;
+			/* FALLTHROUGH */
+		case 4: /* steady underline */
 			XftDrawRect(xw.draw, &drawcol,
 					borderpx + cx * win.cw,
 					borderpx + (cy + 1) * win.ch - \
 						cursorthickness,
 					win.cw, cursorthickness);
 			break;
-		case 5: /* Blinking bar */
-		case 6: /* Steady bar */
+		case 5: /* blinking bar */
+			if (IS_SET(MODE_BLINK))
+				break;
+			/* FALLTHROUGH */
+		case 6: /* steady bar */
 			XftDrawRect(xw.draw, &drawcol,
 					borderpx + cx * win.cw,
 					borderpx + cy * win.ch,
 					cursorthickness, win.ch);
 			break;
+		case 7: /* blinking st cursor */
+			if (IS_SET(MODE_BLINK))
+				break;
+			/* FALLTHROUGH */
+		case 8: /* steady st cursor */
+			g.u = stcursor;
+			xdrawglyph(g, cx, cy);
+			break;
 		}
 	} else {
 		XftDrawRect(xw.draw, &drawcol,
@@ -1708,9 +1724,12 @@ xsetmode(int set, unsigned int flags)
 int
 xsetcursor(int cursor)
 {
-	if (!BETWEEN(cursor, 0, 7)) /* 7: st extension */
+	if (!BETWEEN(cursor, 0, 8)) /* 7-8: st extensions */
 		return 1;
 	win.cursor = cursor;
+	cursorblinks = win.cursor == 0 || win.cursor == 1 ||
+	               win.cursor == 3 || win.cursor == 5 ||
+	               win.cursor == 7;
 	return 0;
 }
 
@@ -1954,6 +1973,10 @@ 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)) \
@@ -1964,7 +1987,7 @@ run(void)
 
 		/* idle detected or maxlatency exhausted -> draw */
 		timeout = -1;
-		if (blinktimeout && tattrset(ATTR_BLINK)) {
+		if (blinktimeout && (cursorblinks || tattrset(ATTR_BLINK))) {
 			timeout = blinktimeout - TIMEDIFF(now, lastblink);
 			if (timeout <= 0) {
 				if (-timeout > blinktimeout) /* start visible */
@@ -2000,7 +2023,7 @@ main(int argc, char *argv[])
 {
 	xw.l = xw.t = 0;
 	xw.isfixed = False;
-	xsetcursor(cursorshape);
+	xsetcursor(cursorstyle);
 
 	ARGBEGIN {
 	case 'a':
-- 
2.34.0