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Diffstat (limited to 'EDK/Foundation/Library/EdkIIGlueLib/Library/BaseUefiDecompressLib/BaseUefiDecompressLib.c')
-rw-r--r--EDK/Foundation/Library/EdkIIGlueLib/Library/BaseUefiDecompressLib/BaseUefiDecompressLib.c892
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diff --git a/EDK/Foundation/Library/EdkIIGlueLib/Library/BaseUefiDecompressLib/BaseUefiDecompressLib.c b/EDK/Foundation/Library/EdkIIGlueLib/Library/BaseUefiDecompressLib/BaseUefiDecompressLib.c
new file mode 100644
index 0000000..72a64b5
--- /dev/null
+++ b/EDK/Foundation/Library/EdkIIGlueLib/Library/BaseUefiDecompressLib/BaseUefiDecompressLib.c
@@ -0,0 +1,892 @@
+/*++
+
+Copyright (c) 2004 - 2011, Intel Corporation
+All rights reserved. This program and the accompanying materials
+are licensed and made available under the terms and conditions of the BSD License
+which accompanies this distribution. The full text of the license may be found at
+http://opensource.org/licenses/bsd-license.php
+
+THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+
+Module Name:
+
+ BaseUefiDecompressLib.c
+
+Abstract:
+
+ UEFI Decompress Library.
+
+--*/
+
+#include "EdkIIGlueBase.h"
+
+//
+// Decompression algorithm begins here
+//
+#define BITBUFSIZ 32
+#define MAXMATCH 256
+#define THRESHOLD 3
+#define CODE_BIT 16
+#define BAD_TABLE - 1
+
+//
+// C: Char&Len Set; P: Position Set; T: exTra Set
+//
+#define NC (0xff + MAXMATCH + 2 - THRESHOLD)
+#define CBIT 9
+#define MAXPBIT 5
+#define TBIT 5
+#define MAXNP ((1U << MAXPBIT) - 1)
+#define NT (CODE_BIT + 3)
+#if NT > MAXNP
+#define NPT NT
+#else
+#define NPT MAXNP
+#endif
+
+typedef struct {
+ UINT8 *mSrcBase; ///< Starting address of compressed data
+ UINT8 *mDstBase; ///< Starting address of decompressed data
+ UINT32 mOutBuf;
+ UINT32 mInBuf;
+
+ UINT16 mBitCount;
+ UINT32 mBitBuf;
+ UINT32 mSubBitBuf;
+ UINT16 mBlockSize;
+ UINT32 mCompSize;
+ UINT32 mOrigSize;
+
+ UINT16 mBadTableFlag;
+
+ UINT16 mLeft[2 * NC - 1];
+ UINT16 mRight[2 * NC - 1];
+ UINT8 mCLen[NC];
+ UINT8 mPTLen[NPT];
+ UINT16 mCTable[4096];
+ UINT16 mPTTable[256];
+
+ ///
+ /// The length of the field 'Position Set Code Length Array Size' in Block Header.
+ /// For EFI 1.1 de/compression algorithm, mPBit = 4
+ /// For Tiano de/compression algorithm, mPBit = 5
+ ///
+ UINT8 mPBit;
+} SCRATCH_DATA;
+
+/**
+ Read NumOfBit of bits from source into mBitBuf
+
+ Shift mBitBuf NumOfBits left. Read in NumOfBits of bits from source.
+
+ @param Sd The global scratch data
+ @param NumOfBits The number of bits to shift and read.
+
+**/
+VOID
+GlueFillBuf (
+ IN SCRATCH_DATA *Sd,
+ IN UINT16 NumOfBits
+ )
+{
+ //
+ // Left shift NumOfBits of bits in advance
+ //
+ Sd->mBitBuf = (UINT32) (Sd->mBitBuf << NumOfBits);
+
+ //
+ // Copy data needed in bytes into mSbuBitBuf
+ //
+ while (NumOfBits > Sd->mBitCount) {
+
+ Sd->mBitBuf |= (UINT32) (Sd->mSubBitBuf << (NumOfBits = (UINT16) (NumOfBits - Sd->mBitCount)));
+
+ if (Sd->mCompSize > 0) {
+ //
+ // Get 1 byte into SubBitBuf
+ //
+ Sd->mCompSize--;
+ Sd->mSubBitBuf = Sd->mSrcBase[Sd->mInBuf++];
+ Sd->mBitCount = 8;
+
+ } else {
+ //
+ // No more bits from the source, just pad zero bit.
+ //
+ Sd->mSubBitBuf = 0;
+ Sd->mBitCount = 8;
+
+ }
+ }
+
+ //
+ // Caculate additional bit count read to update mBitCount
+ //
+ Sd->mBitCount = (UINT16) (Sd->mBitCount - NumOfBits);
+
+ //
+ // Copy NumOfBits of bits from mSubBitBuf into mBitBuf
+ //
+ Sd->mBitBuf |= Sd->mSubBitBuf >> Sd->mBitCount;
+}
+
+/**
+ Get NumOfBits of bits out from mBitBuf
+
+ Get NumOfBits of bits out from mBitBuf. Fill mBitBuf with subsequent
+ NumOfBits of bits from source. Returns NumOfBits of bits that are
+ popped out.
+
+ @param Sd The global scratch data.
+ @param NumOfBits The number of bits to pop and read.
+
+ @return The bits that are popped out.
+
+**/
+UINT32
+GlueGetBits (
+ IN SCRATCH_DATA *Sd,
+ IN UINT16 NumOfBits
+ )
+{
+ UINT32 OutBits;
+
+ //
+ // Pop NumOfBits of Bits from Left
+ //
+ OutBits = (UINT32) (Sd->mBitBuf >> (BITBUFSIZ - NumOfBits));
+
+ //
+ // Fill up mBitBuf from source
+ //
+ FillBuf (Sd, NumOfBits);
+
+ return OutBits;
+}
+
+/**
+ Creates Huffman Code mapping table according to code length array.
+
+ Creates Huffman Code mapping table for Extra Set, Char&Len Set
+ and Position Set according to code length array.
+
+ @param Sd The global scratch data
+ @param NumOfChar Number of symbols in the symbol set
+ @param BitLen Code length array
+ @param TableBits The width of the mapping table
+ @param Table The table
+
+ @retval 0 OK.
+ @retval BAD_TABLE The table is corrupted.
+
+**/
+UINT16
+GlueMakeTable (
+ IN SCRATCH_DATA *Sd,
+ IN UINT16 NumOfChar,
+ IN UINT8 *BitLen,
+ IN UINT16 TableBits,
+ OUT UINT16 *Table
+ )
+{
+ UINT16 Count[17];
+ UINT16 Weight[17];
+ UINT16 Start[18];
+ UINT16 *Pointer;
+ UINT16 Index3;
+ volatile UINT16 Index;
+ UINT16 Len;
+ UINT16 Char;
+ UINT16 JuBits;
+ UINT16 Avail;
+ UINT16 NextCode;
+ UINT16 Mask;
+
+ //
+ // TableBits should not be greater than 16.
+ //
+ if (TableBits >= (sizeof (Count)/sizeof (UINT16))) {
+ return (UINT16) BAD_TABLE;
+ }
+
+ //
+ // Initializing Start
+ //
+ for (Index = 0; Index <= 17; Index++) {
+ Start[Index] = 0;
+ }
+
+ //
+ // Initialize Count array starting from Index 0, as there is a possibility of Count array being uninitialized.
+ //
+ for (Index = 0; Index <= 16; Index++) {
+ Count[Index] = 0;
+ }
+
+ for (Index = 0; Index < NumOfChar; Index++) {
+ //
+ // Count array index should not be greater than or equal to its size.
+ //
+ if (BitLen[Index] < (sizeof (Count)/sizeof (UINT16))) {
+ Count[BitLen[Index]]++;
+ } else {
+ return (UINT16) BAD_TABLE;
+ }
+ }
+
+ Start[1] = 0;
+
+ for (Index = 1; Index <= 16; Index++) {
+ Start[Index + 1] = (UINT16) (Start[Index] + (Count[Index] << (16 - Index)));
+ }
+
+ if (Start[17] != 0) {
+ /*(1U << 16)*/
+ return (UINT16) BAD_TABLE;
+ }
+
+ JuBits = (UINT16) (16 - TableBits);
+
+ for (Index = 1; Index <= TableBits; Index++) {
+ Start[Index] >>= JuBits;
+ Weight[Index] = (UINT16) (1U << (TableBits - Index));
+ }
+
+ while (Index <= 16) {
+ Weight[Index] = (UINT16) (1U << (16 - Index));
+ Index++;
+ }
+
+ Index = (UINT16) (Start[TableBits + 1] >> JuBits);
+
+ if (Index != 0) {
+ Index3 = (UINT16) (1U << TableBits);
+ while (Index != Index3) {
+ Table[Index++] = 0;
+ }
+ }
+
+ Avail = NumOfChar;
+ Mask = (UINT16) (1U << (15 - TableBits));
+
+ for (Char = 0; Char < NumOfChar; Char++) {
+
+ Len = BitLen[Char];
+ if (Len == 0) {
+ continue;
+ }
+
+ NextCode = (UINT16) (Start[Len] + Weight[Len]);
+
+ if (Len <= TableBits) {
+
+ for (Index = Start[Len]; Index < NextCode; Index++) {
+ Table[Index] = Char;
+ }
+
+ } else {
+
+ Index3 = Start[Len];
+ Pointer = &Table[Index3 >> JuBits];
+ Index = (UINT16) (Len - TableBits);
+
+ while (Index != 0) {
+ //
+ // Avail should be lesser than size of mRight and mLeft to prevent buffer overflow.
+ //
+ if ((*Pointer == 0) && (Avail < sizeof (Sd->mRight)/sizeof (UINT16)) && (Avail < sizeof (Sd->mLeft)/sizeof (UINT16))) {
+ Sd->mRight[Avail] = Sd->mLeft[Avail] = 0;
+ *Pointer = Avail++;
+ }
+
+ //
+ // *Pointer should be lesser than size of mRight and mLeft to prevent buffer overflow.
+ //
+ if ((Index3 & Mask) && (*Pointer < (sizeof (Sd->mRight)/sizeof (UINT16)))) {
+ Pointer = &Sd->mRight[*Pointer];
+ } else if (*Pointer < (sizeof (Sd->mLeft)/sizeof (UINT16))) {
+ Pointer = &Sd->mLeft[*Pointer];
+ }
+
+ Index3 <<= 1;
+ Index--;
+ }
+
+ *Pointer = Char;
+
+ }
+
+ Start[Len] = NextCode;
+ }
+ //
+ // Succeeds
+ //
+ return 0;
+}
+
+/**
+ Decodes a position value.
+
+ Get a position value according to Position Huffman Table.
+
+ @param Sd the global scratch data
+
+ @return The position value decoded.
+
+**/
+UINT32
+GlueDecodeP (
+ IN SCRATCH_DATA *Sd
+ )
+{
+ UINT16 Val;
+ UINT32 Mask;
+ UINT32 Pos;
+
+ Val = Sd->mPTTable[Sd->mBitBuf >> (BITBUFSIZ - 8)];
+
+ if (Val >= MAXNP) {
+ Mask = 1U << (BITBUFSIZ - 1 - 8);
+
+ do {
+
+ if (Sd->mBitBuf & Mask) {
+ Val = Sd->mRight[Val];
+ } else {
+ Val = Sd->mLeft[Val];
+ }
+
+ Mask >>= 1;
+ } while (Val >= MAXNP);
+ }
+ //
+ // Advance what we have read
+ //
+ FillBuf (Sd, Sd->mPTLen[Val]);
+
+ Pos = Val;
+ if (Val > 1) {
+ Pos = (UINT32) ((1U << (Val - 1)) + GetBits (Sd, (UINT16) (Val - 1)));
+ }
+
+ return Pos;
+}
+
+/**
+ Reads code lengths for the Extra Set or the Position Set.
+
+ Read in the Extra Set or Pointion Set Length Arrary, then
+ generate the Huffman code mapping for them.
+
+ @param Sd The global scratch data.
+ @param nn Number of symbols.
+ @param nbit Number of bits needed to represent nn.
+ @param Special The special symbol that needs to be taken care of.
+
+ @retval 0 OK.
+ @retval BAD_TABLE Table is corrupted.
+
+**/
+UINT16
+GlueReadPTLen (
+ IN SCRATCH_DATA *Sd,
+ IN UINT16 nn,
+ IN UINT16 nbit,
+ IN UINT16 Special
+ )
+{
+ UINT16 Number;
+ UINT16 CharC;
+ volatile UINT16 Index;
+ UINT32 Mask;
+
+ //
+ // Read Extra Set Code Length Array size
+ //
+ Number = (UINT16) GetBits (Sd, nbit);
+
+ if ((Number > sizeof (Sd->mPTLen)) || (nn > sizeof (Sd->mPTLen))) {
+ //
+ // Fail if Number or nn is greater than size of mPTLen
+ //
+ return (UINT16) BAD_TABLE;
+ }
+
+ if (Number == 0) {
+ //
+ // This represents only Huffman code used
+ //
+ CharC = (UINT16) GetBits (Sd, nbit);
+
+ for (Index = 0; Index < 256; Index++) {
+ Sd->mPTTable[Index] = CharC;
+ }
+
+ for (Index = 0; Index < nn; Index++) {
+ Sd->mPTLen[Index] = 0;
+ }
+
+ return 0;
+ }
+
+ Index = 0;
+
+ while (Index < Number) {
+
+ CharC = (UINT16) (Sd->mBitBuf >> (BITBUFSIZ - 3));
+
+ //
+ // If a code length is less than 7, then it is encoded as a 3-bit
+ // value. Or it is encoded as a series of "1"s followed by a
+ // terminating "0". The number of "1"s = Code length - 4.
+ //
+ if (CharC == 7) {
+ Mask = 1U << (BITBUFSIZ - 1 - 3);
+ while (Mask & Sd->mBitBuf) {
+ Mask >>= 1;
+ CharC += 1;
+ }
+ }
+
+ FillBuf (Sd, (UINT16) ((CharC < 7) ? 3 : CharC - 3));
+
+ Sd->mPTLen[Index++] = (UINT8) CharC;
+
+ //
+ // For Code&Len Set,
+ // After the third length of the code length concatenation,
+ // a 2-bit value is used to indicated the number of consecutive
+ // zero lengths after the third length.
+ //
+ if (Index == Special) {
+ CharC = (UINT16) GetBits (Sd, 2);
+ while ((INT16) (--CharC) >= 0) {
+ if (Index >= sizeof (Sd->mPTLen)) {
+ //
+ // Fail if Index is greater than or equal to mPTLen
+ //
+ return (UINT16) BAD_TABLE;
+ }
+ Sd->mPTLen[Index++] = 0;
+ }
+ }
+ }
+
+ while (Index < nn) {
+ Sd->mPTLen[Index++] = 0;
+ }
+
+ return MakeTable (Sd, nn, Sd->mPTLen, 8, Sd->mPTTable);
+}
+
+/**
+ Reads code lengths for Char&Len Set.
+
+ Read in and decode the Char&Len Set Code Length Array, then
+ generate the Huffman Code mapping table for the Char&Len Set.
+
+ @param Sd the global scratch data
+
+**/
+VOID
+GlueReadCLen (
+ SCRATCH_DATA *Sd
+ )
+{
+ UINT16 Number;
+ UINT16 CharC;
+ volatile UINT16 Index;
+ UINT32 Mask;
+
+ Number = (UINT16) GetBits (Sd, CBIT);
+
+ if (Number == 0) {
+ //
+ // This represents only Huffman code used
+ //
+ CharC = (UINT16) GetBits (Sd, CBIT);
+
+ for (Index = 0; Index < NC; Index++) {
+ Sd->mCLen[Index] = 0;
+ }
+
+ for (Index = 0; Index < 4096; Index++) {
+ Sd->mCTable[Index] = CharC;
+ }
+
+ return ;
+ }
+
+ Index = 0;
+ while (Index < Number) {
+ CharC = Sd->mPTTable[Sd->mBitBuf >> (BITBUFSIZ - 8)];
+ if (CharC >= NT) {
+ Mask = 1U << (BITBUFSIZ - 1 - 8);
+
+ do {
+
+ if (Mask & Sd->mBitBuf) {
+ CharC = Sd->mRight[CharC];
+ } else {
+ CharC = Sd->mLeft[CharC];
+ }
+
+ Mask >>= 1;
+
+ } while (CharC >= NT);
+ }
+ //
+ // Advance what we have read
+ //
+ FillBuf (Sd, Sd->mPTLen[CharC]);
+
+ if (CharC <= 2) {
+
+ if (CharC == 0) {
+ CharC = 1;
+ } else if (CharC == 1) {
+ CharC = (UINT16) (GetBits (Sd, 4) + 3);
+ } else if (CharC == 2) {
+ CharC = (UINT16) (GetBits (Sd, CBIT) + 20);
+ }
+
+ while ((INT16) (--CharC) >= 0) {
+ Sd->mCLen[Index++] = 0;
+ }
+
+ } else {
+
+ Sd->mCLen[Index++] = (UINT8) (CharC - 2);
+
+ }
+ }
+
+ while (Index < NC) {
+ Sd->mCLen[Index++] = 0;
+ }
+
+ MakeTable (Sd, NC, Sd->mCLen, 12, Sd->mCTable);
+
+ return ;
+}
+
+/**
+ Decode a character/length value.
+
+ Read one value from mBitBuf, Get one code from mBitBuf. If it is at block boundary, generates
+ Huffman code mapping table for Extra Set, Code&Len Set and
+ Position Set.
+
+ @param Sd The global scratch data.
+
+ @return The value decoded.
+
+**/
+UINT16
+GlueDecodeC (
+ SCRATCH_DATA *Sd
+ )
+{
+ UINT16 Index2;
+ UINT32 Mask;
+
+ if (Sd->mBlockSize == 0) {
+ //
+ // Starting a new block
+ // Read BlockSize from block header
+ //
+ Sd->mBlockSize = (UINT16) GetBits (Sd, 16);
+
+ //
+ // Read in the Extra Set Code Length Arrary,
+ // Generate the Huffman code mapping table for Extra Set.
+ //
+ Sd->mBadTableFlag = ReadPTLen (Sd, NT, TBIT, 3);
+ if (Sd->mBadTableFlag != 0) {
+ return 0;
+ }
+
+ //
+ // Read in and decode the Char&Len Set Code Length Arrary,
+ // Generate the Huffman code mapping table for Char&Len Set.
+ //
+ ReadCLen (Sd);
+
+ //
+ // Read in the Position Set Code Length Arrary,
+ // Generate the Huffman code mapping table for the Position Set.
+ //
+ Sd->mBadTableFlag = ReadPTLen (Sd, MAXNP, Sd->mPBit, (UINT16) (-1));
+ if (Sd->mBadTableFlag != 0) {
+ return 0;
+ }
+ }
+
+ //
+ // Get one code according to Code&Set Huffman Table
+ //
+ Sd->mBlockSize--;
+ Index2 = Sd->mCTable[Sd->mBitBuf >> (BITBUFSIZ - 12)];
+
+ if (Index2 >= NC) {
+ Mask = 1U << (BITBUFSIZ - 1 - 12);
+
+ do {
+ if (Sd->mBitBuf & Mask) {
+ Index2 = Sd->mRight[Index2];
+ } else {
+ Index2 = Sd->mLeft[Index2];
+ }
+
+ Mask >>= 1;
+ } while (Index2 >= NC);
+ }
+ //
+ // Advance what we have read
+ //
+ FillBuf (Sd, Sd->mCLen[Index2]);
+
+ return Index2;
+}
+
+/**
+ Decode the source data and put the resulting data into the destination buffer.
+
+ Decode the source data and put the resulting data into the destination buffer.
+
+ @param Sd The global scratch data
+
+**/
+VOID
+GlueDecode (
+ SCRATCH_DATA *Sd
+ )
+{
+ UINT16 BytesRemain;
+ UINT32 DataIdx;
+ UINT16 CharC;
+
+ BytesRemain = (UINT16) (-1);
+
+ DataIdx = 0;
+
+ for (;;) {
+ //
+ // Get one code from mBitBuf
+ //
+ CharC = DecodeC (Sd);
+ if (Sd->mBadTableFlag != 0) {
+ return ;
+ }
+
+ if (CharC < 256) {
+ //
+ // Process an Original character
+ //
+ if (Sd->mOutBuf >= Sd->mOrigSize) {
+ return ;
+ } else {
+ //
+ // Write orignal character into mDstBase
+ //
+ Sd->mDstBase[Sd->mOutBuf++] = (UINT8) CharC;
+ }
+
+ } else {
+ //
+ // Process a Pointer
+ //
+ CharC = (UINT16) (CharC - (UINT8_MAX + 1 - THRESHOLD));
+
+ //
+ // Get string length
+ //
+ BytesRemain = CharC;
+
+ //
+ // Locate string position
+ //
+ DataIdx = Sd->mOutBuf - DecodeP (Sd) - 1;
+
+ //
+ // Write BytesRemain of bytes into mDstBase
+ //
+ BytesRemain--;
+ while ((INT16) (BytesRemain) >= 0) {
+ Sd->mDstBase[Sd->mOutBuf++] = Sd->mDstBase[DataIdx++];
+ if (Sd->mOutBuf >= Sd->mOrigSize) {
+ return ;
+ }
+
+ BytesRemain--;
+ }
+ }
+ }
+
+ return ;
+}
+
+/**
+ Retrieves the size of the uncompressed buffer and the size of the scratch buffer.
+
+ Retrieves the size of the uncompressed buffer and the temporary scratch buffer
+ required to decompress the buffer specified by Source and SourceSize.
+ If the size of the uncompressed buffer or the size of the scratch buffer cannot
+ be determined from the compressed data specified by Source and SourceData,
+ then RETURN_INVALID_PARAMETER is returned. Otherwise, the size of the uncompressed
+ buffer is returned in DestinationSize, the size of the scratch buffer is returned
+ in ScratchSize, and RETURN_SUCCESS is returned.
+ This function does not have scratch buffer available to perform a thorough
+ checking of the validity of the source data. It just retrieves the "Original Size"
+ field from the beginning bytes of the source data and output it as DestinationSize.
+ And ScratchSize is specific to the decompression implementation.
+
+ If Source is NULL, then ASSERT().
+ If DestinationSize is NULL, then ASSERT().
+ If ScratchSize is NULL, then ASSERT().
+
+ @param Source The source buffer containing the compressed data.
+ @param SourceSize The size, in bytes, of the source buffer.
+ @param DestinationSize A pointer to the size, in bytes, of the uncompressed buffer
+ that will be generated when the compressed buffer specified
+ by Source and SourceSize is decompressed..
+ @param ScratchSize A pointer to the size, in bytes, of the scratch buffer that
+ is required to decompress the compressed buffer specified
+ by Source and SourceSize.
+
+ @retval RETURN_SUCCESS The size of destination buffer and the size of scratch
+ buffer are successull retrieved.
+ @retval RETURN_INVALID_PARAMETER The source data is corrupted
+
+**/
+RETURN_STATUS
+EFIAPI
+UefiDecompressGetInfo (
+ IN CONST VOID *Source,
+ IN UINT32 SourceSize,
+ OUT UINT32 *DestinationSize,
+ OUT UINT32 *ScratchSize
+ )
+{
+ UINT32 CompressedSize;
+
+ ASSERT (Source != NULL);
+ ASSERT (DestinationSize != NULL);
+ ASSERT (ScratchSize != NULL);
+
+ *ScratchSize = sizeof (SCRATCH_DATA);
+
+ if (SourceSize < 8) {
+ return RETURN_INVALID_PARAMETER;
+ }
+
+ CopyMem (&CompressedSize, Source, sizeof (UINT32));
+ CopyMem (DestinationSize, (VOID *)((UINT8 *)Source + 4), sizeof (UINT32));
+
+ if (SourceSize < (CompressedSize + 8)) {
+ return RETURN_INVALID_PARAMETER;
+ }
+
+ return RETURN_SUCCESS;
+}
+
+/**
+ Decompresses a compressed source buffer.
+
+ This function is designed so that the decompression algorithm can be implemented
+ without using any memory services. As a result, this function is not allowed to
+ call any memory allocation services in its implementation. It is the caller¡¯s r
+ esponsibility to allocate and free the Destination and Scratch buffers.
+ If the compressed source data specified by Source is sucessfully decompressed
+ into Destination, then RETURN_SUCCESS is returned. If the compressed source data
+ specified by Source is not in a valid compressed data format,
+ then RETURN_INVALID_PARAMETER is returned.
+
+ If Source is NULL, then ASSERT().
+ If Destination is NULL, then ASSERT().
+ If the required scratch buffer size > 0 and Scratch is NULL, then ASSERT().
+
+ @param Source The source buffer containing the compressed data.
+ @param Destination The destination buffer to store the decompressed data
+ @param Scratch A temporary scratch buffer that is used to perform the decompression.
+ This is an optional parameter that may be NULL if the
+ required scratch buffer size is 0.
+
+ @retval RETURN_SUCCESS Decompression is successfull
+ @retval RETURN_INVALID_PARAMETER The source data is corrupted
+
+**/
+RETURN_STATUS
+EFIAPI
+UefiDecompress (
+ IN CONST VOID *Source,
+ IN OUT VOID *Destination,
+ IN OUT VOID *Scratch
+ )
+{
+ volatile UINT32 Index;
+ UINT32 CompSize;
+ UINT32 OrigSize;
+ SCRATCH_DATA *Sd;
+ CONST UINT8 *Src;
+ UINT8 *Dst;
+
+ ASSERT (Source != NULL);
+ ASSERT (Destination != NULL);
+ ASSERT (Scratch != NULL);
+
+ Src = Source;
+ Dst = Destination;
+
+ Sd = (SCRATCH_DATA *) Scratch;
+
+ CompSize = Src[0] + (Src[1] << 8) + (Src[2] << 16) + (Src[3] << 24);
+ OrigSize = Src[4] + (Src[5] << 8) + (Src[6] << 16) + (Src[7] << 24);
+
+ //
+ // If compressed file size is 0, return
+ //
+ if (OrigSize == 0) {
+ return RETURN_SUCCESS;
+ }
+
+ Src = Src + 8;
+
+ for (Index = 0; Index < sizeof (SCRATCH_DATA); Index++) {
+ ((UINT8 *) Sd)[Index] = 0;
+ }
+ //
+ // The length of the field 'Position Set Code Length Array Size' in Block Header.
+ // For EFI 1.1 de/compression algorithm(Version 1), mPBit = 4
+ // For Tiano de/compression algorithm(Version 2), mPBit = 5
+ //
+ Sd->mPBit = 4;
+ Sd->mSrcBase = (UINT8 *)Src;
+ Sd->mDstBase = Dst;
+ //
+ // CompSize and OrigSize are caculated in bytes
+ //
+ Sd->mCompSize = CompSize;
+ Sd->mOrigSize = OrigSize;
+
+ //
+ // Fill the first BITBUFSIZ bits
+ //
+ FillBuf (Sd, BITBUFSIZ);
+
+ //
+ // Decompress it
+ //
+ Decode (Sd);
+
+ if (Sd->mBadTableFlag != 0) {
+ //
+ // Something wrong with the source
+ //
+ return RETURN_INVALID_PARAMETER;
+ }
+
+ return RETURN_SUCCESS;
+}