CSI 22, 23

This patch adds support for CSI escape sequences 22 and 23,
which save and restore window title (for instance nvim does
this when opening and closing).

https://st.suckless.org/patches/csi_22_23/

1 files changed, 38 insertions, 3 deletions

diff --git a/x.c b/x.c
index 6b55d05..80b5d12 100644
--- a/x.c
+++ b/x.c
@@ -64,6 +64,9 @@ static void ttysend(const Arg *);
 /* config.h for applying patches and the configuration. */
 #include "config.h"
 
+/* size of title stack */
+#define TITLESTACKSIZE 8
+
 /* XEMBED messages */
 #define XEMBED_FOCUS_IN  4
 #define XEMBED_FOCUS_OUT 5
@@ -224,6 +227,8 @@ static DC dc;
 static XWindow xw;
 static XSelection xsel;
 static TermWindow win;
+static int tstki; /* title stack index */
+static char *titlestack[TITLESTACKSIZE]; /* title stack */
 
 /* Font Ring Cache */
 enum {
@@ -1752,10 +1757,30 @@ xseticontitle(char *p)
 }
 
 void
-xsettitle(char *p)
+xfreetitlestack(void)
 {
-	XTextProperty prop;
-	DEFAULT(p, opt_title);
+	for (int i = 0; i < LEN(titlestack); i++) {
+		free(titlestack[i]);
+		titlestack[i] = NULL;
+	}
+}
+
+void
+xsettitle(char *p, int pop)
+{
+ 	XTextProperty prop;
+ 
+	free(titlestack[tstki]);
+	if (pop) {
+		titlestack[tstki] = NULL;
+		tstki = (tstki - 1 + TITLESTACKSIZE) % TITLESTACKSIZE;
+		p = titlestack[tstki] ? titlestack[tstki] : opt_title;
+	} else if (p) {
+		titlestack[tstki] = xstrdup(p);
+	} else {
+		titlestack[tstki] = NULL;
+		p = opt_title;
+	}
 
 	if (p[0] == '\0')
 		p = opt_title;
@@ -1768,6 +1793,16 @@ xsettitle(char *p)
 	XFree(prop.value);
 }
 
+void
+xpushtitle(void)
+{
+	int tstkin = (tstki + 1) % TITLESTACKSIZE;
+
+	free(titlestack[tstkin]);
+	titlestack[tstkin] = titlestack[tstki] ? xstrdup(titlestack[tstki]) : NULL;
+	tstki = tstkin;
+}
+
 int
 xstartdraw(void)
 {