Cygwin/X: Make winOverrrideStyle() thread-safe

Make winOverrrideStyle() thread-safe

winOverrideStyle() is called from the internal WM client thread.

Accessing server-internal data structures to get window name and
class is not safe, as there is no lock to ensure we do not collide
with these data structures being updated in the server thread.

Rewrite so the internal client thread uses X client calls to
obtain this data safely

Signed-off-by: Jon TURNEY <jon.turney@dronecode.org.uk>
Reviewed-by: Colin Harrison <colin.harrison@virgin.net>
Tested-by: Colin Harrison <colin.harrison@virgin.net>

3 files changed, 24 insertions, 26 deletions

diff --git a/hw/xwin/winmultiwindowwm.c b/hw/xwin/winmultiwindowwm.c
index ef0c7cf0b..67a58a076 100644
--- a/hw/xwin/winmultiwindowwm.c
+++ b/hw/xwin/winmultiwindowwm.c
@@ -1576,7 +1576,6 @@ winApplyHints (Display *pDisplay, Window iWindow, HWND hWnd, HWND *zstyle)
   Atom			type, *pAtom = NULL;
   int			format;
   unsigned long		hint = 0, maxmin = 0, style, nitems = 0 , left = 0;
-  WindowPtr		pWin = GetProp (hWnd, WIN_WINDOW_PROP);
   MwmHints              *mwm_hint = NULL;
 
   if (!hWnd) return;
@@ -1669,7 +1668,26 @@ winApplyHints (Display *pDisplay, Window iWindow, HWND hWnd, HWND *zstyle)
   }
 
   /* Override hint settings from above with settings from config file */
-  style = winOverrideStyle((unsigned long)pWin);
+  {
+    XClassHint class_hint = {0,0};
+    char *window_name = 0;
+
+    if (XGetClassHint(pDisplay, iWindow, &class_hint))
+      {
+        XFetchName(pDisplay, iWindow, &window_name);
+
+        style = winOverrideStyle(class_hint.res_name, class_hint.res_class, window_name);
+
+        if (class_hint.res_name) XFree(class_hint.res_name);
+        if (class_hint.res_class) XFree(class_hint.res_class);
+        if (window_name) XFree(window_name);
+      }
+    else
+      {
+        style = STYLE_NONE;
+      }
+  }
+
   if (style & STYLE_TOPMOST) *zstyle = HWND_TOPMOST;
   else if (style & STYLE_MAXIMIZE) maxmin = (hint & ~HINT_MIN) | HINT_MAX;
   else if (style & STYLE_MINIMIZE) maxmin = (hint & ~HINT_MAX) | HINT_MIN;
diff --git a/hw/xwin/winprefs.c b/hw/xwin/winprefs.c
index 4ccb4ffc2..d941c5169 100644
--- a/hw/xwin/winprefs.c
+++ b/hw/xwin/winprefs.c
@@ -813,40 +813,20 @@ LoadPreferences (void)
  * STYLES{} section in the prefs file, and return the style type
  */
 unsigned long
-winOverrideStyle (unsigned long longpWin)
+winOverrideStyle (char *res_name, char *res_class, char *wmName)
 {
-  WindowPtr pWin = (WindowPtr) longpWin;
-  char *res_name, *res_class;
   int i;
-  char *wmName;
-
-  if (pWin==NULL)
-    return STYLE_NONE;
-
-  /* If we can't find the class, we can't override from default! */
-  if (!winMultiWindowGetClassHint (pWin, &res_name, &res_class))
-    return STYLE_NONE;
-
-  winMultiWindowGetWMName (pWin, &wmName);
 
   for (i=0; i<pref.styleItems; i++) {
-    if (!strcmp(pref.style[i].match, res_name) ||
-	!strcmp(pref.style[i].match, res_class) ||
+    if ((res_name && !strcmp(pref.style[i].match, res_name)) ||
+	(res_class && !strcmp(pref.style[i].match, res_class)) ||
 	(wmName && strstr(wmName, pref.style[i].match)))
       {
-	free (res_name);
-	free (res_class);
-	free(wmName);
-
 	if (pref.style[i].type)
 	  return pref.style[i].type;
       }
   }
 
   /* Didn't find the style, fail gracefully */
-  free (res_name);
-  free (res_class);
-  free(wmName);
-
   return STYLE_NONE;
 }
diff --git a/hw/xwin/winprefs.h b/hw/xwin/winprefs.h
index 33b496df8..ecd0a3fbd 100644
--- a/hw/xwin/winprefs.h
+++ b/hw/xwin/winprefs.h
@@ -180,7 +180,7 @@ HICON
 winOverrideIcon (unsigned long longpWin);
 
 unsigned long
-winOverrideStyle (unsigned long longpWin);
+winOverrideStyle (char *res_name, char *res_class, char *wmName);
 
 HICON
 winTaskbarIcon(void);