From 69f14e7d37b4d074e740797e51d99ea82b39ec33 Mon Sep 17 00:00:00 2001
From: Raheman Vaiya <r.vaiya@gmail.com>
Date: Sun, 26 Dec 2021 18:57:04 +0100
Subject: [PATCH] Add support for OSC color sequences

---
 config.def.h |  5 +--
 st.c         | 90 +++++++++++++++++++++++++++++++++++-----------------
 st.h         |  2 ++
 3 files changed, 66 insertions(+), 31 deletions(-)

diff --git a/config.def.h b/config.def.h
index bb5bda8..e282b67 100644
--- a/config.def.h
+++ b/config.def.h
@@ -123,6 +123,7 @@ static const char *colorname[] = {
 	/* more colors can be added after 255 to use with DefaultXX */
 	"#cccccc",
 	"#555555",
+	"gray90", /* default foreground colour */
 	"black", /* default background colour */
 };
 
@@ -131,8 +132,8 @@ static const char *colorname[] = {
  * Default colors (colorname index)
  * foreground, background, cursor, reverse cursor
  */
-unsigned int defaultfg = 7;
-unsigned int defaultbg = 258;
+unsigned int defaultfg = 258;
+unsigned int defaultbg = 259;
 unsigned int defaultcs = 256;
 static unsigned int defaultrcs = 257;
 
diff --git a/st.c b/st.c
index 332d73e..93fdbf1 100644
--- a/st.c
+++ b/st.c
@@ -168,7 +168,7 @@ static void csidump(void);
 static void csihandle(void);
 static void csiparse(void);
 static void csireset(void);
-static void osc_color_response(int, int, int);
+static void osc_color_response(int, int);
 static int eschandle(uchar);
 static void strdump(void);
 static void strhandle(void);
@@ -1898,28 +1898,39 @@ csireset(void)
 }
 
 void
-osc_color_response(int num, int index, int is_osc4)
+osc4_color_response(int num)
 {
 	int n;
 	char buf[32];
 	unsigned char r, g, b;
 
-	if (xgetcolor(is_osc4 ? num : index, &r, &g, &b)) {
-		fprintf(stderr, "erresc: failed to fetch %s color %d\n",
-		        is_osc4 ? "osc4" : "osc",
-		        is_osc4 ? num : index);
+	if (xgetcolor(num, &r, &g, &b)) {
+		fprintf(stderr, "erresc: failed to fetch osc4 color %d\n", num);
 		return;
 	}
 
-	n = snprintf(buf, sizeof buf, "\033]%s%d;rgb:%02x%02x/%02x%02x/%02x%02x\007",
-	             is_osc4 ? "4;" : "", num, r, r, g, g, b, b);
-	if (n < 0 || n >= sizeof(buf)) {
-		fprintf(stderr, "error: %s while printing %s response\n",
-		        n < 0 ? "snprintf failed" : "truncation occurred",
-		        is_osc4 ? "osc4" : "osc");
-	} else {
-		ttywrite(buf, n, 1);
+	n = snprintf(buf, sizeof buf, "\033]4;%d;rgb:%02x%02x/%02x%02x/%02x%02x\007",
+		     num, r, r, g, g, b, b);
+
+	ttywrite(buf, n, 1);
+}
+
+void
+osc_color_response(int index, int num)
+{
+	int n;
+	char buf[32];
+	unsigned char r, g, b;
+
+	if (xgetcolor(index, &r, &g, &b)) {
+		fprintf(stderr, "erresc: failed to fetch osc color %d\n", index);
+		return;
 	}
+
+	n = snprintf(buf, sizeof buf, "\033]%d;rgb:%02x%02x/%02x%02x/%02x%02x\007",
+		     num, r, r, g, g, b, b);
+
+	ttywrite(buf, n, 1);
 }
 
 void
@@ -1966,23 +1977,44 @@ strhandle(void)
 			}
 			return;
 		case 10:
+			if (narg < 2)
+				break;
+
+			p = strescseq.args[1];
+
+			if (!strcmp(p, "?"))
+				osc_color_response(defaultfg, 10);
+			else if (xsetcolorname(defaultfg, p))
+				fprintf(stderr, "erresc: invalid foreground color: %s\n", p);
+			else
+				redraw();
+			break;
 		case 11:
+			if (narg < 2)
+				break;
+
+			p = strescseq.args[1];
+
+			if (!strcmp(p, "?"))
+				osc_color_response(defaultbg, 11);
+			else if (xsetcolorname(defaultbg, p))
+				fprintf(stderr, "erresc: invalid background color: %s\n", p);
+			else
+				redraw();
+			break;
 		case 12:
 			if (narg < 2)
 				break;
+
 			p = strescseq.args[1];
-			if ((j = par - 10) < 0 || j >= LEN(osc_table))
-				break; /* shouldn't be possible */
-
-			if (!strcmp(p, "?")) {
-				osc_color_response(par, osc_table[j].idx, 0);
-			} else if (xsetcolorname(osc_table[j].idx, p)) {
-				fprintf(stderr, "erresc: invalid %s color: %s\n",
-				        osc_table[j].str, p);
-			} else {
-				tfulldirt();
-			}
-			return;
+
+			if (!strcmp(p, "?"))
+				osc_color_response(defaultcs, 12);
+			else if (xsetcolorname(defaultcs, p))
+				fprintf(stderr, "erresc: invalid cursor color: %s\n", p);
+			else
+				redraw();
+			break;
 		case 4: /* color set */
 			if (narg < 3)
 				break;
@@ -1991,9 +2023,9 @@ strhandle(void)
 		case 104: /* color reset */
 			j = (narg > 1) ? atoi(strescseq.args[1]) : -1;
 
-			if (p && !strcmp(p, "?")) {
-				osc_color_response(j, 0, 1);
-			} else if (xsetcolorname(j, p)) {
+			if (!strcmp(p, "?"))
+				osc4_color_response(j);
+			else if (xsetcolorname(j, p)) {
 				if (par == 104 && narg <= 1)
 					return; /* color reset without parameter */
 				fprintf(stderr, "erresc: invalid color j=%d, p=%s\n",
diff --git a/st.h b/st.h
index bb2caa8..1d5693b 100644
--- a/st.h
+++ b/st.h
@@ -114,6 +114,8 @@ void *xmalloc(size_t);
 void *xrealloc(void *, size_t);
 char *xstrdup(const char *);
 
+int xgetcolor(int x, unsigned char *r, unsigned char *g, unsigned char *b);
+
 /* config.h globals */
 extern char *utmp;
 extern char *scroll;
-- 
2.43.0