[PATCH 0/1] MR5389: kernel32, ntdll: Don't use debug info presence to detect critical section global status.

[Paul Gofman (＠gofman)]

See https://gitlab.winehq.org/wine/wine/-/merge_requests/5379 , this is an alternative way which doesn't remove MakeCriticalSectionGlobal() functionality.

[PATCH 1/1] kernel32, ntdll: Don't use debug info presence to detect critical section global status.

[Paul Gofman]

From: Paul Gofman

---
 dlls/kernel32/sync.c |  2 +-
 dlls/ntdll/sync.c    | 37 +++++++++++--------------------------
 2 files changed, 12 insertions(+), 27 deletions(-)

diff --git a/dlls/kernel32/sync.c b/dlls/kernel32/sync.c
index 53419cd4618..f1d3a6ef561 100644
--- a/dlls/kernel32/sync.c
+++ b/dlls/kernel32/sync.c
@@ -128,7 +128,7 @@ void WINAPI MakeCriticalSectionGlobal( CRITICAL_SECTION *crit )
 {
     /* let's assume that only one thread at a time will try to do this */
     HANDLE sem = crit->LockSemaphore;
-    if (!sem) NtCreateSemaphore( &sem, SEMAPHORE_ALL_ACCESS, NULL, 0, 1 );
+    if (!sem || ((ULONG_PTR)sem & 3)) NtCreateSemaphore( &sem, SEMAPHORE_ALL_ACCESS, NULL, 0, 1 );
     crit->LockSemaphore = ConvertToGlobalHandle( sem );
     if (crit->DebugInfo != (void *)(ULONG_PTR)-1)
         RtlFreeHeap( GetProcessHeap(), 0, crit->DebugInfo );
diff --git a/dlls/ntdll/sync.c b/dlls/ntdll/sync.c
index 00ab614803f..2c950d2bb91 100644
--- a/dlls/ntdll/sync.c
+++ b/dlls/ntdll/sync.c
@@ -163,29 +163,17 @@ static const char *crit_section_get_name( const RTL_CRITICAL_SECTION *crit )

static inline HANDLE get_semaphore( RTL_CRITICAL_SECTION *crit )
 {
-    HANDLE ret = crit->LockSemaphore;
-    if (!ret)
-    {
-        HANDLE sem;
-        if (NtCreateSemaphore( &sem, SEMAPHORE_ALL_ACCESS, NULL, 0, 1 )) return 0;
-        if (!(ret = InterlockedCompareExchangePointer( &crit->LockSemaphore, sem, 0 )))
-            ret = sem;
-        else
-            NtClose(sem);  /* somebody beat us to it */
-    }
-    return ret;
+    if (crit->LockSemaphore && !((ULONG_PTR)crit->LockSemaphore & 3)) return crit->LockSemaphore;
+    return NULL;
 }

static inline NTSTATUS wait_semaphore( RTL_CRITICAL_SECTION *crit, int timeout )
 {
     LARGE_INTEGER time = {.QuadPart = timeout * (LONGLONG)-10000000};
+    HANDLE sem;

/* debug info is cleared by MakeCriticalSectionGlobal */
-    if (!crit_section_has_debuginfo( crit ))
-    {
-        HANDLE sem = get_semaphore( crit );
-        return NtWaitForSingleObject( sem, FALSE, &time );
-    }
+    if ((sem = get_semaphore( crit ))) return NtWaitForSingleObject( sem, FALSE, &time );
     else
     {
         LONG *lock = (LONG *)&crit->LockSemaphore;
@@ -276,6 +264,8 @@ ULONG WINAPI RtlSetCriticalSectionSpinCount( RTL_CRITICAL_SECTION *crit, ULONG s
  */
 NTSTATUS WINAPI RtlDeleteCriticalSection( RTL_CRITICAL_SECTION *crit )
 {
+    HANDLE sem;
+
     crit->LockCount      = -1;
     crit->RecursionCount = 0;
     crit->OwningThread   = 0;
@@ -288,11 +278,9 @@ NTSTATUS WINAPI RtlDeleteCriticalSection( RTL_CRITICAL_SECTION *crit )
             crit->DebugInfo = NULL;
         }
     }
-    else
-    {
-        NtClose( crit->LockSemaphore );
-        crit->DebugInfo = NULL;
-    }
+    else crit->DebugInfo = NULL;
+
+    if ((sem = get_semaphore( crit ))) NtClose( sem );
     crit->LockSemaphore = 0;
     return STATUS_SUCCESS;
 }
@@ -335,13 +323,10 @@ NTSTATUS WINAPI RtlpWaitForCriticalSection( RTL_CRITICAL_SECTION *crit )
 NTSTATUS WINAPI RtlpUnWaitCriticalSection( RTL_CRITICAL_SECTION *crit )
 {
     NTSTATUS ret;
+    HANDLE sem;

/* debug info is cleared by MakeCriticalSectionGlobal */
-    if (!crit_section_has_debuginfo( crit ))
-    {
-        HANDLE sem = get_semaphore( crit );
-        ret = NtReleaseSemaphore( sem, 1, NULL );
-    }
+    if ((sem = get_semaphore( crit ))) ret = NtReleaseSemaphore( sem, 1, NULL );
     else
     {
         LONG *lock = (LONG *)&crit->LockSemaphore;