[PATCH v2 3/6] uiautomationcore: Shutdown provider thread when all returned nodes are released.

[Connor McAdams]

From: Connor McAdams

Signed-off-by: Connor McAdams 
---
 dlls/uiautomationcore/uia_client.c   | 18 +++---------------
 dlls/uiautomationcore/uia_private.h  | 20 ++++++++++++++++++++
 dlls/uiautomationcore/uia_provider.c | 22 +++++++++++++++++++++-
 3 files changed, 44 insertions(+), 16 deletions(-)

diff --git a/dlls/uiautomationcore/uia_client.c b/dlls/uiautomationcore/uia_client.c
index 0ff01eba5af..c1fb880c9f1 100644
--- a/dlls/uiautomationcore/uia_client.c
+++ b/dlls/uiautomationcore/uia_client.c
@@ -269,21 +269,6 @@ static IRawElementProviderSimple *get_provider_hwnd_fragment_root(IRawElementPro
 /*
  * IWineUiaNode interface.
  */
-struct uia_node {
-    IWineUiaNode IWineUiaNode_iface;
-    LONG ref;
-
-    IWineUiaProvider *prov;
-    DWORD git_cookie;
-
-    HWND hwnd;
-};
-
-static inline struct uia_node *impl_from_IWineUiaNode(IWineUiaNode *iface)
-{
-    return CONTAINING_RECORD(iface, struct uia_node, IWineUiaNode_iface);
-}
-
 static HRESULT WINAPI uia_node_QueryInterface(IWineUiaNode *iface, REFIID riid, void **ppv)
 {
     *ppv = NULL;
@@ -328,6 +313,9 @@ static ULONG WINAPI uia_node_Release(IWineUiaNode *iface)
         }

IWineUiaProvider_Release(node->prov);
+        if (node->nested_node)
+            uia_stop_provider_thread();
+
         heap_free(node);
     }

diff --git a/dlls/uiautomationcore/uia_private.h b/dlls/uiautomationcore/uia_private.h
index f92d4bd3721..1efc8fbd1e4 100644
--- a/dlls/uiautomationcore/uia_private.h
+++ b/dlls/uiautomationcore/uia_private.h
@@ -29,4 +29,24 @@ enum uia_prop_type {
     PROP_TYPE_SPECIAL,
 };

+struct uia_node {
+    IWineUiaNode IWineUiaNode_iface;
+    LONG ref;
+
+    IWineUiaProvider *prov;
+    DWORD git_cookie;
+
+    HWND hwnd;
+    BOOL nested_node;
+};
+
+static inline struct uia_node *impl_from_IWineUiaNode(IWineUiaNode *iface)
+{
+    return CONTAINING_RECORD(iface, struct uia_node, IWineUiaNode_iface);
+}
+
+/* uia_ids.c */
 const struct uia_prop_info *uia_prop_info_from_id(PROPERTYID prop_id) DECLSPEC_HIDDEN;
+
+/* uia_provider.c */
+void uia_stop_provider_thread(void) DECLSPEC_HIDDEN;
diff --git a/dlls/uiautomationcore/uia_provider.c b/dlls/uiautomationcore/uia_provider.c
index f05a3e1ff8a..94aa1948871 100644
--- a/dlls/uiautomationcore/uia_provider.c
+++ b/dlls/uiautomationcore/uia_provider.c
@@ -1132,6 +1132,7 @@ struct uia_provider_thread
 {
     HANDLE hthread;
     HWND hwnd;
+    LONG ref;
 };

static struct uia_provider_thread provider_thread;
@@ -1145,6 +1146,7 @@ static CRITICAL_SECTION_DEBUG provider_thread_cs_debug =
 static CRITICAL_SECTION provider_thread_cs = { &provider_thread_cs_debug, -1, 0, 0, 0, 0 };

#define WM_GET_OBJECT_UIA_NODE (WM_USER + 1)
+#define WM_UIA_PROVIDER_THREAD_STOP (WM_USER + 2)
 static LRESULT CALLBACK uia_provider_thread_msg_proc(HWND hwnd, UINT msg, WPARAM wparam,
         LPARAM lparam)
 {
@@ -1153,8 +1155,12 @@ static LRESULT CALLBACK uia_provider_thread_msg_proc(HWND hwnd, UINT msg, WPARAM
     case WM_GET_OBJECT_UIA_NODE:
     {
         HUIANODE node = (HUIANODE)lparam;
+        struct uia_node *node_data;
         LRESULT lr;

+        node_data = impl_from_IWineUiaNode((IWineUiaNode *)node);
+        node_data->nested_node = TRUE;
+
         /*
          * LresultFromObject returns an index into the global atom string table,
          * which has a valid range of 0xc000-0xffff.
@@ -1204,6 +1210,8 @@ static DWORD WINAPI uia_provider_thread_proc(void *arg)
     TRACE("Provider thread started.\n");
     while (GetMessageW(&msg, NULL, 0, 0))
     {
+        if (msg.message == WM_UIA_PROVIDER_THREAD_STOP)
+            break;
         TranslateMessage(&msg);
         DispatchMessageW(&msg);
     }
@@ -1220,7 +1228,7 @@ static BOOL uia_start_provider_thread(void)
     BOOL started = TRUE;

EnterCriticalSection(&provider_thread_cs);
-    if (!IsWindow(provider_thread.hwnd))
+    if (++provider_thread.ref == 1)
     {
         HANDLE ready_event;
         HANDLE events[2];
@@ -1261,6 +1269,18 @@ exit:
     return started;
 }

+void uia_stop_provider_thread(void)
+{
+    EnterCriticalSection(&provider_thread_cs);
+    if (!--provider_thread.ref)
+    {
+        PostMessageW(provider_thread.hwnd, WM_UIA_PROVIDER_THREAD_STOP, 0, 0);
+        CloseHandle(provider_thread.hthread);
+        memset(&provider_thread, 0, sizeof(provider_thread));
+    }
+    LeaveCriticalSection(&provider_thread_cs);
+}
+
 /*
  * Pass our IWineUiaNode interface to the provider thread for marshaling. UI
  * Automation has to work regardless of whether or not COM is initialized on