[SDK] Minor improvements to CRT, RTL, and headers

Signed-off-by: Quinn Stephens <quinn@osmora.org>

SDK/INC/NT/ntrtl.h

@@ -16,9 +16,9 @@ Abstract:
 #ifndef _NTRTL_H
 #define _NTRTL_H
 
-#include <string.h>
-#include <ntdef.h>
-#include <ntstatus.h>
+#ifdef __cplusplus
+extern "C" {
+#endif
 
 //
 // Memory operations.
@@ -28,7 +28,128 @@ Abstract:
 #define RtlFillMemory(Destination, Length, Fill)   memset((Destination), (Fill), (Length))
 #define RtlZeroMemory(Destination, Length)         memset((Destination), 0, (Length))
 
-#define ULONG_ERROR 0xFFFFFFFFUL
+FORCEINLINE
+VOID
+InitializeListHead (
+    IN PLIST_ENTRY Head
+    )
+
+/*++
+
+Routine Description:
+
+    Initializes a list head.
+
+Arguments:
+
+    Head - Pointer to the list's head.
+
+Return Value:
+
+    None.
+
+--*/
+
+{
+    Head->Blink = Head;
+    Head->Flink = Head;
+}
+
+FORCEINLINE
+VOID
+InsertHeadList (
+    IN PLIST_ENTRY Head,
+    IN PLIST_ENTRY Entry
+    )
+
+/*++
+
+Routine Description:
+
+    Inserts an entry at the head of a list.
+
+Arguments:
+
+    Entry - Pointer to the list entry to insert.
+
+Return Value:
+
+    None.
+
+--*/
+
+{
+    Entry->Flink = Head->Flink;
+    Entry->Blink = Head;
+    Head->Flink->Blink = Entry;
+    Head->Flink = Entry;
+}
+
+FORCEINLINE
+VOID
+InsertTailList (
+    IN PLIST_ENTRY Head,
+    IN PLIST_ENTRY Entry
+    )
+
+/*++
+
+Routine Description:
+
+    Inserts an entry at the tail of a list.
+
+Arguments:
+
+    Entry - Pointer to the list entry to insert.
+
+Return Value:
+
+    None.
+
+--*/
+
+{
+    Entry->Blink = Head->Blink;
+    Entry->Flink = Head;
+    Head->Blink->Flink = Entry;
+    Head->Blink = Entry;
+}
+
+FORCEINLINE
+BOOLEAN
+RemoveEntryList (
+    IN PLIST_ENTRY Entry
+    )
+
+/*++
+
+Routine Description:
+
+    Removes an entry from a list.
+
+Arguments:
+
+    Entry - Pointer to the entry to remove.
+
+Return Value:
+
+    TRUE if the list is now empty,
+    FALSE if the list still has at least one entry.
+
+--*/
+
+{
+    PLIST_ENTRY Blink, Flink;
+
+    Blink = Entry->Blink;
+    Flink = Entry->Flink;
+    Blink->Flink = Flink;
+    Flink->Blink = Blink;
+
+    return (BOOLEAN)(Flink == Blink);
+}
+
+#define ULONG_ERROR 0xffffffffUL
 
 FORCEINLINE
 NTSTATUS
@@ -83,4 +204,8 @@ RtlGUIDFromString (
    OUT GUID *Guid
    );
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif /* !_NTRTL_H */