[PATCH 0/1] MR2941: riched20: Set empty text by default in CreateTextServices.

[Santino Mazza (＠tati1454)]

This is to prevent NULL pointers when creating a standalone text service
that doesn't have any text set and then using functions like EM_SETSEL.
This NULL pointers doesn't happen when creating a richedit windows, because
it sets an empty text when the richedit window procedure handles the WM_CREATE event.

-- 
https://gitlab.winehq.org/wine/wine/-/merge_requests/2941

[PATCH 1/1] riched20: Set empty text by default in CreateTextServices.

[Santino Mazza]

From: Santino Mazza <smazza(a)codeweavers.com>

This is to prevent NULL pointers when creating a standalone text service
that doesn't have any text set and then using functions like EM_SETSEL.
This NULL pointers doesn't happen when creating a richedit windows, because
it sets an empty text when the richedit window procedure handles the WM_CREATE event.
---
 dlls/riched20/tests/txtsrv.c | 22 +++++++++++++++++++++-
 dlls/riched20/txtsrv.c       | 14 +++++++++++++-
 2 files changed, 34 insertions(+), 2 deletions(-)

diff --git a/dlls/riched20/tests/txtsrv.c b/dlls/riched20/tests/txtsrv.c
index d75db465ce4..79f0cee6f55 100644
--- a/dlls/riched20/tests/txtsrv.c
+++ b/dlls/riched20/tests/txtsrv.c
@@ -620,7 +620,7 @@ static BOOL init_texthost(ITextServices **txtserv, ITextHost **ret)
     memset(&dummyTextHost->char_format, 0, sizeof(dummyTextHost->char_format));
     dummyTextHost->char_format.cbSize = sizeof(dummyTextHost->char_format);
     dummyTextHost->char_format.dwMask = CFM_ALL2;
-    dummyTextHost->scrollbars = 0;
+    dummyTextHost->scrollbars = ES_AUTOVSCROLL;
     dummyTextHost->props = 0;
     hf = GetStockObject(DEFAULT_GUI_FONT);
     hf_to_cf(hf, &dummyTextHost->char_format);
@@ -746,6 +746,25 @@ static void test_TxSetText(void)
     ITextHost_Release(host);
 }
 
+static void test_set_selection_message(void)
+{
+    ITextServices *txtserv;
+    ITextHost *host;
+    HRESULT result;
+
+    if (!init_texthost(&txtserv, &host))
+        return;
+
+    result = ITextServices_TxSendMessage(txtserv, EM_SETSEL, 0, 20, NULL);
+    ok(result == S_OK, "ITextServices_TxSendMessaage failed (result = %lx)\n", result);
+
+    result = ITextServices_TxSendMessage(txtserv, EM_SETSEL, 20, 0, NULL);
+    ok(result == S_OK, "ITextServices_TxSendMessaage failed (result = %lx)\n", result);
+
+    ITextServices_Release(txtserv);
+    ITextHost_Release(host);
+}
+
 #define CHECK_TXGETNATURALSIZE(res,width,height,hdc,rect,string) \
     _check_txgetnaturalsize(res, width, height, hdc, rect, string, __LINE__)
 static void _check_txgetnaturalsize(HRESULT res, LONG width, LONG height, HDC hdc, RECT rect, LPCWSTR string, int line)
@@ -1267,6 +1286,7 @@ START_TEST( txtsrv )
 
         test_TxGetText();
         test_TxSetText();
+        test_set_selection_message();
         test_TxGetNaturalSize();
         test_TxDraw();
         test_QueryInterface();
diff --git a/dlls/riched20/txtsrv.c b/dlls/riched20/txtsrv.c
index 55e0c7e64bb..f232f9ec95c 100644
--- a/dlls/riched20/txtsrv.c
+++ b/dlls/riched20/txtsrv.c
@@ -608,5 +608,17 @@ HRESULT create_text_services( IUnknown *outer, ITextHost *text_host, IUnknown **
  */
 HRESULT WINAPI CreateTextServices( IUnknown *outer, ITextHost *text_host, IUnknown **unk )
 {
-    return create_text_services( outer, text_host, unk, FALSE );
+    HRESULT hr;
+    ITextServices *serv;
+
+    hr = create_text_services( outer, text_host, unk, FALSE );
+    if (hr != S_OK) return hr;
+
+    hr = IUnknown_QueryInterface(*unk, &IID_ITextServices, (void**)&serv);
+    if (hr != S_OK) return hr;
+
+    ITextServices_TxSetText(serv, NULL);
+    ITextServices_Release(serv);
+
+    return S_OK;
 }
-- 
GitLab

https://gitlab.winehq.org/wine/wine/-/merge_requests/2941

[PATCH 1/1] riched20: Set empty text by default in CreateTextServices.

[Jactry Zeng]

Hi Santino,

On 5/31/23 14:29, Santino Mazza wrote:
> +    hr = IUnknown_QueryInterface(*unk, &IID_ITextServices, (void**)&serv);
> +    if (hr != S_OK) return hr;
> +

Likely memory that is allocated in create_text_services() will be leaked 
while returning from here.