[PATCH v7 1/1] imm32: Prevent deadlock on unload

[Fabian Maurer]

From: Fabian Maurer

ole32 is delay loaded, which can cause race conditions against
krnl386.exe when unloading.
This is because imm32 tries to get the loader lock while holding the win16 mutex,
and kernel386 does the opposite.

Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=52511
Signed-off-by: Fabian Maurer 
---
 dlls/imm32/imm.c | 22 ++++++++++++++++++++--
 1 file changed, 20 insertions(+), 2 deletions(-)

diff --git a/dlls/imm32/imm.c b/dlls/imm32/imm.c
index 780d544c0e9..d58376048f4 100644
--- a/dlls/imm32/imm.c
+++ b/dlls/imm32/imm.c
@@ -80,6 +80,9 @@ typedef struct _tagImmHkl{
     DWORD (WINAPI *pImeGetImeMenuItems)(HIMC, DWORD, DWORD, IMEMENUITEMINFOW *, IMEMENUITEMINFOW *, DWORD);
 } ImmHkl;

+static HRESULT (WINAPI *pCoRevokeInitializeSpy)(ULARGE_INTEGER cookie);
+static void (WINAPI *pCoUninitialize)(void);
+
 typedef struct tagInputContextData
 {
         HIMC            handle;
@@ -249,7 +252,7 @@ static void imm_couninit_thread(BOOL cleanup)

if (cleanup && spy->cookie.QuadPart)
     {
-        CoRevokeInitializeSpy(spy->cookie);
+        pCoRevokeInitializeSpy(spy->cookie);
         spy->cookie.QuadPart = 0;
     }

@@ -261,7 +264,7 @@ static void imm_couninit_thread(BOOL cleanup)
     {
         spy->apt_flags &= ~IMM_APT_CREATED;
         if (spy->apt_flags & IMM_APT_CAN_FREE)
-            CoUninitialize();
+            pCoUninitialize();
     }
     if (cleanup)
         spy->apt_flags = 0;
@@ -359,13 +362,28 @@ static const IInitializeSpyVtbl InitializeSpyVtbl =
     InitializeSpy_PostUninitialize,
 };

+static BOOL WINAPI init_ole32_funcs( INIT_ONCE *once, void *param, void **context )
+{
+    HMODULE module_ole32 = GetModuleHandleA("ole32");
+    pCoRevokeInitializeSpy = (void*)GetProcAddress(module_ole32, "CoRevokeInitializeSpy");
+    pCoUninitialize = (void*)GetProcAddress(module_ole32, "CoUninitialize");
+    return pCoRevokeInitializeSpy && pCoUninitialize;
+}
+
 static void imm_coinit_thread(void)
 {
     struct coinit_spy *spy;
     HRESULT hr;
+    static INIT_ONCE init_ole32_once = INIT_ONCE_STATIC_INIT;

TRACE("implicit COM initialization\n");

+    if (!InitOnceExecuteOnce(&init_ole32_once, init_ole32_funcs, NULL, NULL))
+    {
+        ERR("Initialization failed\n");
+        return;
+    }
+
     if (!(spy = get_thread_coinit_spy()))
     {
         if (!(spy = HeapAlloc(GetProcessHeap(), 0, sizeof(*spy)))) return;