Publish the files

Sources/Platform/EFI/EfiBitmap.c

@@ -0,0 +1,98 @@
+/*!
+    @file EfiBitmap.c
+
+    @brief EFI specific implementation of bitmap algorithm.
+
+    @details Implementation of algorithm is good enough for the current use of
+        those API but is incomplete and broken, for example, bits are NEVER
+        reused once they are set, even after they are "cleared".
+
+        For complete implementation, one can copy ReactOS's implementation if
+        licensing the project under GPL is acceptable. hvpp by wbenny has its own
+        implementation of bitmap but is actually influenced by ReactOS
+        implementation and such should be treated as GPL.
+
+    @author Satoshi Tanda
+
+    @copyright Copyright (c) 2020 - , Satoshi Tanda. All rights reserved.
+ */
+#include "EfiBitmap.h"
+
+VOID
+RtlInitializeBitMap (
+    RTL_BITMAP* BitMapHeader,
+    UINT32* BitMapBuffer,
+    UINT32 SizeOfBitMap
+    )
+{
+    BitMapHeader->SizeOfBitMap = SizeOfBitMap;
+    BitMapHeader->Buffer = BitMapBuffer;
+    BitMapHeader->NextAvailableBitIndex = 0;
+    BitMapHeader->SetBitCount = 0;
+}
+
+UINT32
+RtlFindClearBitsAndSet (
+    RTL_BITMAP* BitMapHeader,
+    UINT32 NumberToFind,
+    UINT32 HintIndex
+    )
+{
+    UINT32 clearBitIndex;
+
+    //
+    // Return error if the bitmap does not have enough bits after the current
+    // index. In other words, it never search from the index 0 because implementation
+    // never clears bits.
+    //
+    if (BitMapHeader->NextAvailableBitIndex + NumberToFind > BitMapHeader->SizeOfBitMap)
+    {
+        clearBitIndex = MAXUINT32;
+        goto Exit;
+    }
+
+    //
+    // "Find" clear bits, which is just using bits from the current position.
+    //
+    clearBitIndex = BitMapHeader->NextAvailableBitIndex;
+
+    //
+    // "Set" requested bits, which is just moving the index further.
+    //
+    BitMapHeader->SetBitCount += NumberToFind;
+    BitMapHeader->NextAvailableBitIndex += NumberToFind;
+
+Exit:
+    return clearBitIndex;
+}
+
+BOOLEAN
+RtlAreBitsClear (
+    RTL_BITMAP* BitMapHeader,
+    UINT32 StartingIndex,
+    UINT32 Length
+    )
+{
+    //
+    // This implementation support checking only whether an entire bitmap is
+    // cleared.
+    //
+    ASSERT(StartingIndex == 0);
+    ASSERT(Length == BitMapHeader->SizeOfBitMap);
+
+    return (BitMapHeader->SetBitCount == 0);
+}
+
+VOID
+RtlClearBits (
+    RTL_BITMAP* BitMapHeader,
+    UINT32 StartingIndex,
+    UINT32 NumberToClear
+    )
+{
+    //
+    // This implementation only change this counter, and never actually clear
+    // bits and let them to be re-set.
+    //
+    BitMapHeader->SetBitCount -= NumberToClear;
+}