[PATCH v8 0/2] MR5238: krnl386, mmsystem: Simulate a hardware interrupt in MMSYSTDRV_Callback3216.

[Alex Henrie (＠alexhenrie)]

Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=56260

--
  v8: mmsystem: Simulate a hardware interrupt in MMSYSTDRV_Callback3216.
      krnl386: Add a WOWCallback16Ex flag to simulate a hardware interrupt.

https://gitlab.winehq.org/wine/wine/-/merge_requests/5238

[PATCH v8 1/2] krnl386: Add a WOWCallback16Ex flag to simulate a hardware interrupt.

[Alex Henrie]

From: Alex Henrie

Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=56260
---
 dlls/krnl386.exe16/wowthunk.c | 8 ++++----
 include/wownt32.h             | 3 +++
 2 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/dlls/krnl386.exe16/wowthunk.c b/dlls/krnl386.exe16/wowthunk.c
index b729c38e8f1..6962e041fc8 100644
--- a/dlls/krnl386.exe16/wowthunk.c
+++ b/dlls/krnl386.exe16/wowthunk.c
@@ -460,9 +460,9 @@ BOOL WINAPI K32WOWCallback16Ex( DWORD vpfn16, DWORD dwFlags,
         *((SEGPTR *)stack) = call16_ret_addr;
         cbArgs += sizeof(SEGPTR);

-        _EnterWin16Lock();
+        if (!(dwFlags & WCB16_INTERRUPT)) _EnterWin16Lock();
         wine_call_to_16_regs( context, cbArgs, call16_handler );
-        _LeaveWin16Lock();
+        if (!(dwFlags & WCB16_INTERRUPT)) _LeaveWin16Lock();

if (TRACE_ON(relay))
         {
@@ -500,10 +500,10 @@ BOOL WINAPI K32WOWCallback16Ex( DWORD vpfn16, DWORD dwFlags,
          * the callee to do so; after the routine has returned, the 16-bit
          * stack pointer is always reset to the position it had before.
          */
-        _EnterWin16Lock();
+        if (!(dwFlags & WCB16_INTERRUPT)) _EnterWin16Lock();
         ret = wine_call_to_16( (FARPROC16)vpfn16, cbArgs, call16_handler );
         if (pdwRetCode) *pdwRetCode = ret;
-        _LeaveWin16Lock();
+        if (!(dwFlags & WCB16_INTERRUPT)) _LeaveWin16Lock();

if (TRACE_ON(relay))
         {
diff --git a/include/wownt32.h b/include/wownt32.h
index 0afe23d360a..b95dce97171 100644
--- a/include/wownt32.h
+++ b/include/wownt32.h
@@ -149,6 +149,9 @@ WORD   WINAPI WOWHandle16(HANDLE,WOW_HANDLE_TYPE);

/* Wine extensions: call register function, context ptr is passed in the return value LPDWORD */
 #define WCB16_REGS       2
+/* Wine extension: simulate a hardware interrupt by running the callback without waiting for the
+ * current task to yield */
+#define WCB16_INTERRUPT  4

DWORD WINAPI WOWCallback16(DWORD,DWORD);
 BOOL  WINAPI WOWCallback16Ex(DWORD,DWORD,DWORD,LPVOID,LPDWORD);

[PATCH v8 2/2] mmsystem: Simulate a hardware interrupt in MMSYSTDRV_Callback3216.

[Alex Henrie]

From: Alex Henrie

Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=56260
---
 dlls/mmsystem.dll16/message16.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/dlls/mmsystem.dll16/message16.c b/dlls/mmsystem.dll16/message16.c
index b12b9b94327..f201b807c3f 100644
--- a/dlls/mmsystem.dll16/message16.c
+++ b/dlls/mmsystem.dll16/message16.c
@@ -838,7 +838,7 @@ static LRESULT CALLBACK MMSYSTDRV_Callback3216(struct mmsystdrv_thunk* thunk, HD
         args[2] = LOWORD(dwParam1);
         args[1] = HIWORD(dwParam2);
         args[0] = LOWORD(dwParam2);
-        return WOWCallback16Ex(thunk->callback, WCB16_PASCAL, sizeof(args), args, NULL);
+        return WOWCallback16Ex(thunk->callback, WCB16_PASCAL | WCB16_INTERRUPT, sizeof(args), args, NULL);
     case CALLBACK_EVENT:
         TRACE("Event(%08lx) !\n", thunk->callback);
         SetEvent((HANDLE)thunk->callback);

[Alex Henrie (＠alexhenrie)]

On Thu Feb 20 04:41:23 2025 +0000, Alexandre Julliard wrote:
> Please don't add Wine-specific exports. You could simply pass a new flag
> to WOWCallback16Ex.

Thanks for the suggestion. I didn't realize that there was precedent for Wine-specific WOWCallback16Ex flags, but now I see that `WCB16_REGS` is also a Wine extension.