From e195854e00a726bf5b381e801752b8af47725050 Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Mon, 20 Nov 2017 20:20:48 +0530
Subject: [PATCH] Support for setting WM_CLASS on a per-window basis

---
 include/GLFW/glfw3.h |  7 ++++++-
 src/x11_window.c     | 29 ++++++++++++++++++++++++-----
 2 files changed, 30 insertions(+), 6 deletions(-)

diff --git a/include/GLFW/glfw3.h b/include/GLFW/glfw3.h
index a3f986407..67c2d495b 100644
--- a/include/GLFW/glfw3.h
+++ b/include/GLFW/glfw3.h
@@ -2343,7 +2343,12 @@ GLFWAPI void glfwWindowHint(int hint, int value);
  *  @remark @x11 The name and class of the `WM_CLASS` window property will by
  *  default be set to the window title passed to this function.  Set the @ref
  *  GLFW_X11_WM_CLASS_NAME and @ref GLFW_X11_WM_CLASS_CLASS init hints before
- *  initialization to override this.
+ *  initialization to override this. You can also set the title int he following
+ *  special format, which allows setting the two parts of the WM_CLASS property
+ *  and the window title independently:
+ *  <01> WM_CLASS name <30> WM_CLASS class <30> title
+ *  Here <01> refers to the byte value 01 (ASCII start-of-header) and <30> refers
+ *  to the byte value 30 (ASCII record separator).
  *
  *  @remark @wayland The window frame is currently unimplemented, as if
  *  [GLFW_DECORATED](@ref GLFW_DECORATED_hint) was always set to `GLFW_FALSE`.
diff --git a/src/x11_window.c b/src/x11_window.c
index 32fff63b6..0cc49d744 100644
--- a/src/x11_window.c
+++ b/src/x11_window.c
@@ -703,9 +703,11 @@ static GLFWbool createNativeWindow(_GLFWwindow* window,
 
     updateNormalHints(window, wndconfig->width, wndconfig->height);
 
-    // Set ICCCM WM_CLASS property
+    // Set ICCCM WM_CLASS property and window title
     {
         XClassHint* hint = XAllocClassHint();
+        char *wm_cclass = NULL, *wm_cname = NULL;
+        const char *real_title = wndconfig->title;
 
         if (strlen(_glfw.hints.init.x11.className) &&
             strlen(_glfw.hints.init.x11.classClass))
@@ -713,10 +715,26 @@ static GLFWbool createNativeWindow(_GLFWwindow* window,
             hint->res_name = (char*) _glfw.hints.init.x11.className;
             hint->res_class = (char*) _glfw.hints.init.x11.classClass;
         }
-        else if (strlen(wndconfig->title))
+        else if (strlen(real_title))
         {
-            hint->res_name = (char*) wndconfig->title;
-            hint->res_class = (char*) wndconfig->title;
+            if (*real_title == 1) {
+                char *p = strchr(real_title, 30);
+                if (p && p > real_title + 1) {
+                    wm_cname = calloc(p - real_title + 1, 1);
+                    if (wm_cname) memcpy(wm_cname, real_title + 1, p - real_title - 1);
+                    hint->res_name = wm_cname;
+                    char *q = strchr(p + 1, 30);
+                    if (q && q > p + 1) {
+                        wm_cclass = calloc(q - p + 1, 1);
+                        if (wm_cclass) memcpy(wm_cclass, p + 1, q - p - 1);
+                        hint->res_class = wm_cclass;
+                        real_title = q + 1;
+                    }
+                }
+            } else {
+                hint->res_name = (char*) real_title;
+                hint->res_class = (char*) real_title;
+            }
         }
         else
         {
@@ -726,6 +744,8 @@ static GLFWbool createNativeWindow(_GLFWwindow* window,
 
         XSetClassHint(_glfw.x11.display, window->x11.handle, hint);
         XFree(hint);
+        free(wm_cclass); free(wm_cname);
+        _glfwPlatformSetWindowTitle(window, real_title);
     }
 
     // Announce support for Xdnd (drag and drop)
@@ -736,7 +756,6 @@ static GLFWbool createNativeWindow(_GLFWwindow* window,
                         PropModeReplace, (unsigned char*) &version, 1);
     }
 
-    _glfwPlatformSetWindowTitle(window, wndconfig->title);
 
     if (_glfw.x11.im)
     {