[PATCH] riched20: Check for NULL in fnTextSrv_TxSetText and add test

[Fabian Maurer]

Fixes https://bugs.winehq.org/show_bug.cgi?id=12185

Signed-off-by: Fabian Maurer <dark.shadow4 at web.de>
---
 dlls/riched20/tests/txtsrv.c | 3 +++
 dlls/riched20/txtsrv.c       | 7 +++----
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/dlls/riched20/tests/txtsrv.c b/dlls/riched20/tests/txtsrv.c
index 1a6ca61052..6fd77d1b59 100644
--- a/dlls/riched20/tests/txtsrv.c
+++ b/dlls/riched20/tests/txtsrv.c
@@ -681,6 +681,9 @@ static void test_TxSetText(void)
     ok(memcmp(rettext,settext,SysStringByteLen(rettext)) == 0,
                  "String returned differs\n");
 
+    /* Test if we crash when using NULL as text */
+    ITextServices_TxSetText(txtserv, NULL);
+
     SysFreeString(rettext);
     ITextServices_Release(txtserv);
     ITextHost_Release(host);
diff --git a/dlls/riched20/txtsrv.c b/dlls/riched20/txtsrv.c
index 3df779834b..307b484352 100644
--- a/dlls/riched20/txtsrv.c
+++ b/dlls/riched20/txtsrv.c
@@ -286,10 +286,9 @@ DECLSPEC_HIDDEN HRESULT WINAPI fnTextSrv_TxSetText(ITextServices *iface, LPCWSTR
    ME_Cursor cursor;
 
    ME_SetCursorToStart(This->editor, &cursor);
-   ME_InternalDeleteText(This->editor, &cursor,
-                         ME_GetTextLength(This->editor), FALSE);
-   ME_InsertTextFromCursor(This->editor, 0, pszText, -1,
-                           This->editor->pBuffer->pDefaultStyle);
+   ME_InternalDeleteText(This->editor, &cursor, ME_GetTextLength(This->editor), FALSE);
+   if(pszText)
+       ME_InsertTextFromCursor(This->editor, 0, pszText, -1, This->editor->pBuffer->pDefaultStyle);
    ME_SetSelection(This->editor, 0, 0);
    This->editor->nModifyStep = 0;
    OleFlushClipboard();
-- 
2.11.0