[hackers] [st][PATCH] Fix crash on IME restart

From: Ivan Tham <pickfire_AT_riseup.net>
Date: Tue, 29 Jan 2019 13:41:13 +0800

Register XNDestroyCallback on IME to reinstatiate XIM.

This does not solve:
- IME not usable if st started before IME
- st goes blank with two st in a dwm tag after restarting IME, might be
  dwm bug as it is happens to other terminal as well

Steps to reproduce (using dwm):
1. Open `fcitx`
2. Open `st`
3. Close `fcitx`
4. `st` crashed

---
 x.c | 61 +++++++++++++++++++++++++++++++++++++++++++++----------------
 1 file changed, 45 insertions(+), 16 deletions(-)
diff --git a/x.c b/x.c
index 0422421..e5ae6a2 100644
--- a/x.c
+++ b/x.c
_AT_@ -139,6 +139,9 @@ static void xdrawglyphfontspecs(const XftGlyphFontSpec *, Glyph, int, int, int);
 static void xdrawglyph(Glyph, int, int);
 static void xclear(int, int, int, int);
 static int xgeommasktogravity(int);
+static void ximopen(Display *);
+static void ximinstantiate(Display *, XPointer, XPointer);
+static void ximdestroy(XIM, XPointer, XPointer);
 static void xinit(int, int);
 static void cresize(int, int);
 static void xresize(int, int);
_AT_@ -996,6 +999,47 @@ xunloadfonts(void)
 	xunloadfont(&dc.ibfont);
 }
 
+void
+ximopen(Display *dpy)
+{
+	XIMCallback destroy = { .client_data = NULL, .callback = ximdestroy };
+
+	if ((xw.xim = XOpenIM(xw.dpy, NULL, NULL, NULL)) == NULL) {
+		XSetLocaleModifiers("_AT_im=local");
+		if ((xw.xim =  XOpenIM(xw.dpy, NULL, NULL, NULL)) == NULL) {
+			XSetLocaleModifiers("_AT_im=");
+			if ((xw.xim = XOpenIM(xw.dpy,
+					NULL, NULL, NULL)) == NULL) {
+				die("XOpenIM failed. Could not open input"
+					" device.\n");
+			}
+		}
+	}
+	if (XSetIMValues(xw.xim, XNDestroyCallback, &destroy, NULL) != NULL)
+		die("XSetIMValues failed. Could not set input method value.\n");
+	xw.xic = XCreateIC(xw.xim, XNInputStyle,
+				XIMPreeditNothing | XIMStatusNothing,
+				XNClientWindow, xw.win, XNFocusWindow, xw.win, NULL);
+	if (xw.xic == NULL)
+		die("XCreateIC failed. Could not obtain input method.\n");
+}
+
+void
+ximinstantiate(Display *dpy, XPointer client, XPointer call)
+{
+	ximopen(dpy);
+	XUnregisterIMInstantiateCallback(xw.dpy, NULL, NULL, NULL,
+					ximinstantiate, NULL);
+}
+
+void
+ximdestroy(XIM xim, XPointer client, XPointer call)
+{
+	xw.xim = NULL;
+	XRegisterIMInstantiateCallback(xw.dpy, NULL, NULL, NULL,
+					ximinstantiate, NULL);
+}
+
 void
 xinit(int cols, int rows)
 {
_AT_@ -1061,22 +1105,7 @@ xinit(int cols, int rows)
 	xw.draw = XftDrawCreate(xw.dpy, xw.buf, xw.vis, xw.cmap);
 
 	/* input methods */
-	if ((xw.xim = XOpenIM(xw.dpy, NULL, NULL, NULL)) == NULL) {
-		XSetLocaleModifiers("_AT_im=local");
-		if ((xw.xim =  XOpenIM(xw.dpy, NULL, NULL, NULL)) == NULL) {
-			XSetLocaleModifiers("_AT_im=");
-			if ((xw.xim = XOpenIM(xw.dpy,
-					NULL, NULL, NULL)) == NULL) {
-				die("XOpenIM failed. Could not open input"
-					" device.\n");
-			}
-		}
-	}
-	xw.xic = XCreateIC(xw.xim, XNInputStyle, XIMPreeditNothing
-					   | XIMStatusNothing, XNClientWindow, xw.win,
-					   XNFocusWindow, xw.win, NULL);
-	if (xw.xic == NULL)
-		die("XCreateIC failed. Could not obtain input method.\n");
+	ximopen(xw.dpy);
 
 	/* white cursor, black outline */
 	cursor = XCreateFontCursor(xw.dpy, mouseshape);
-- 
2.20.1

Received on Tue Jan 29 2019 - 06:41:13 CET