From: Hermès BÉLUSCA - MAÏTO <hermes.belusca@sfr.fr>
Subject: shell32: Automatically expand CPL applet path string (try 2)
Message-Id: <003701cf53f7$75e56870$61b03950$@sfr.fr>
Date: Wed, 9 Apr 2014 15:27:31 +0200

Symptom: when running �control.exe
%systemroot%\system32\some_custom_cpl.cpl� (or �rundll32.exe
shell32.dll,Control_RunDLL %systemroot%\system32\some_custom_cpl.cpl�, or
even, loading a CPL registered in HKLM\Software\Microsoft\Windows\Control
Panel\Cpls), it fails because the path string is not expanded.
Solution: always expand the CPL applet path string, so that, if it contains
environment variables, they get expanded, and if not, the usual behaviour is
obtained.

 dlls/shell32/control.c |   24 +++++++++++++++++-------
 1 file changed, 17 insertions(+), 7 deletions(-)

diff --git a/dlls/shell32/control.c b/dlls/shell32/control.c
index fe392e3..b393154 100644
--- a/dlls/shell32/control.c
+++ b/dlls/shell32/control.c
@@ -62,6 +62,7 @@ void Control_UnloadApplet(CPlApplet* applet)
 CPlApplet*	Control_LoadApplet(HWND hWnd, LPCWSTR cmd, CPanel* panel)
 {
     CPlApplet*	applet;
+    DWORD len;
     unsigned 	i;
     CPLINFO	info;
     NEWCPLINFOW newinfo;
@@ -69,21 +70,30 @@ CPlApplet*	Control_LoadApplet(HWND hWnd, LPCWSTR cmd, CPanel* panel)
     if (!(applet = HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, sizeof(*applet))))
        return applet;
 
-    if (!(applet->cmd = HeapAlloc(GetProcessHeap(), 0, (lstrlenW(cmd)+1) * sizeof(WCHAR)))) {
-        WARN("Cannot allocate memory for applet path\n");
+    len = ExpandEnvironmentStringsW(cmd, NULL, 0);
+    if (len > 0)
+    {
+        if (!(applet->cmd = HeapAlloc(GetProcessHeap(), 0, (len+1) * sizeof(WCHAR))))
+        {
+            WARN("Cannot allocate memory for applet path\n");
+            goto theError;
+        }
+        ExpandEnvironmentStringsW(cmd, applet->cmd, len+1);
+    }
+    else
+    {
+        WARN("Cannot expand applet path\n");
         goto theError;
     }
 
-    lstrcpyW(applet->cmd, cmd);
-
     applet->hWnd = hWnd;
 
-    if (!(applet->hModule = LoadLibraryW(cmd))) {
-        WARN("Cannot load control panel applet %s\n", debugstr_w(cmd));
+    if (!(applet->hModule = LoadLibraryW(applet->cmd))) {
+        WARN("Cannot load control panel applet %s\n", debugstr_w(applet->cmd));
 	goto theError;
     }
     if (!(applet->proc = (APPLET_PROC)GetProcAddress(applet->hModule, "CPlApplet"))) {
-        WARN("Not a valid control panel applet %s\n", debugstr_w(cmd));
+        WARN("Not a valid control panel applet %s\n", debugstr_w(applet->cmd));
 	goto theError;
     }
     if (!applet->proc(hWnd, CPL_INIT, 0L, 0L)) {