/** @file\r
- UEFI Decompress Library.\r
+ UEFI Decompress Library implementation refer to UEFI specification.\r
\r
- Copyright (c) 2006, Intel Corporation\r
+ Copyright (c) 2006 - 2008, Intel Corporation\r
All rights reserved. This program and the accompanying materials\r
are licensed and made available under the terms and conditions of the BSD License\r
which accompanies this distribution. The full text of the license may be found at\r
THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
\r
- Module Name: UefiDecompressLib.c\r
-\r
**/\r
\r
-//\r
-// Decompression algorithm begins here\r
-//\r
-#define BITBUFSIZ 32\r
-#define MAXMATCH 256\r
-#define THRESHOLD 3\r
-#define CODE_BIT 16\r
-#define BAD_TABLE - 1\r
-\r
-//\r
-// C: Char&Len Set; P: Position Set; T: exTra Set\r
-//\r
-#define NC (0xff + MAXMATCH + 2 - THRESHOLD)\r
-#define CBIT 9\r
-#define MAXPBIT 5\r
-#define TBIT 5\r
-#define MAXNP ((1U << MAXPBIT) - 1)\r
-#define NT (CODE_BIT + 3)\r
-#if NT > MAXNP\r
-#define NPT NT\r
-#else\r
-#define NPT MAXNP\r
-#endif\r
-\r
-typedef struct {\r
- UINT8 *mSrcBase; ///< Starting address of compressed data\r
- UINT8 *mDstBase; ///< Starting address of decompressed data\r
- UINT32 mOutBuf;\r
- UINT32 mInBuf;\r
-\r
- UINT16 mBitCount;\r
- UINT32 mBitBuf;\r
- UINT32 mSubBitBuf;\r
- UINT16 mBlockSize;\r
- UINT32 mCompSize;\r
- UINT32 mOrigSize;\r
-\r
- UINT16 mBadTableFlag;\r
-\r
- UINT16 mLeft[2 * NC - 1];\r
- UINT16 mRight[2 * NC - 1];\r
- UINT8 mCLen[NC];\r
- UINT8 mPTLen[NPT];\r
- UINT16 mCTable[4096];\r
- UINT16 mPTTable[256];\r
-\r
- ///\r
- /// The length of the field 'Position Set Code Length Array Size' in Block Header.\r
- /// For EFI 1.1 de/compression algorithm, mPBit = 4\r
- /// For Tiano de/compression algorithm, mPBit = 5\r
- ///\r
- UINT8 mPBit;\r
-} SCRATCH_DATA;\r
+\r
+#include <Base.h>\r
+\r
+\r
+#include <Library/BaseLib.h>\r
+#include <Library/UefiDecompressLib.h>\r
+#include <Library/DebugLib.h>\r
+\r
+#include "BaseUefiDecompressLibInternals.h"\r
\r
/**\r
+ Read NumOfBit of bits from source into mBitBuf.\r
+\r
Shift mBitBuf NumOfBits left. Read in NumOfBits of bits from source.\r
\r
- @param Sd The global scratch data\r
+ @param Sd The global scratch data\r
@param NumOfBits The number of bits to shift and read.\r
\r
**/\r
IN UINT16 NumOfBits\r
)\r
{\r
+ //\r
+ // Left shift NumOfBits of bits in advance\r
+ //\r
Sd->mBitBuf = (UINT32) (Sd->mBitBuf << NumOfBits);\r
\r
+ //\r
+ // Copy data needed in bytes into mSbuBitBuf\r
+ //\r
while (NumOfBits > Sd->mBitCount) {\r
\r
Sd->mBitBuf |= (UINT32) (Sd->mSubBitBuf << (NumOfBits = (UINT16) (NumOfBits - Sd->mBitCount)));\r
// Get 1 byte into SubBitBuf\r
//\r
Sd->mCompSize--;\r
- Sd->mSubBitBuf = 0;\r
Sd->mSubBitBuf = Sd->mSrcBase[Sd->mInBuf++];\r
Sd->mBitCount = 8;\r
\r
}\r
}\r
\r
+ //\r
+ // Caculate additional bit count read to update mBitCount\r
+ //\r
Sd->mBitCount = (UINT16) (Sd->mBitCount - NumOfBits);\r
+ \r
+ //\r
+ // Copy NumOfBits of bits from mSubBitBuf into mBitBuf\r
+ //\r
Sd->mBitBuf |= Sd->mSubBitBuf >> Sd->mBitCount;\r
}\r
\r
/**\r
+ Get NumOfBits of bits out from mBitBuf.\r
+\r
Get NumOfBits of bits out from mBitBuf. Fill mBitBuf with subsequent \r
NumOfBits of bits from source. Returns NumOfBits of bits that are \r
popped out.\r
\r
- @param Sd The global scratch data.\r
+ @param Sd The global scratch data.\r
@param NumOfBits The number of bits to pop and read.\r
\r
@return The bits that are popped out.\r
{\r
UINT32 OutBits;\r
\r
+ //\r
+ // Pop NumOfBits of Bits from Left\r
+ // \r
OutBits = (UINT32) (Sd->mBitBuf >> (BITBUFSIZ - NumOfBits));\r
\r
+ //\r
+ // Fill up mBitBuf from source\r
+ //\r
FillBuf (Sd, NumOfBits);\r
\r
return OutBits;\r
/**\r
Creates Huffman Code mapping table according to code length array.\r
\r
- @param Sd The global scratch data\r
+ Creates Huffman Code mapping table for Extra Set, Char&Len Set \r
+ and Position Set according to code length array.\r
+\r
+ @param Sd The global scratch data\r
@param NumOfChar Number of symbols in the symbol set\r
- @param BitLen Code length array\r
+ @param BitLen Code length array\r
@param TableBits The width of the mapping table\r
- @param Table The table\r
+ @param Table The table to be created\r
\r
@retval 0 OK.\r
@retval BAD_TABLE The table is corrupted.\r
UINT16 Avail;\r
UINT16 NextCode;\r
UINT16 Mask;\r
+ UINT16 WordOfStart;\r
+ UINT16 WordOfCount;\r
+\r
\r
for (Index = 1; Index <= 16; Index++) {\r
Count[Index] = 0;\r
Start[1] = 0;\r
\r
for (Index = 1; Index <= 16; Index++) {\r
- Start[Index + 1] = (UINT16) (Start[Index] + (Count[Index] << (16 - Index)));\r
+ WordOfStart = Start[Index];\r
+ WordOfCount = Count[Index];\r
+ Start[Index + 1] = (UINT16) (WordOfStart + (WordOfCount << (16 - Index)));\r
}\r
\r
if (Start[17] != 0) {\r
*Pointer = Avail++;\r
}\r
\r
- if (Index3 & Mask) {\r
+ if ((Index3 & Mask) != 0) {\r
Pointer = &Sd->mRight[*Pointer];\r
} else {\r
Pointer = &Sd->mLeft[*Pointer];\r
/**\r
Decodes a position value.\r
\r
+ Get a position value according to Position Huffman Table.\r
+ \r
@param Sd the global scratch data\r
\r
@return The position value decoded.\r
\r
do {\r
\r
- if (Sd->mBitBuf & Mask) {\r
+ if ((Sd->mBitBuf & Mask) != 0) {\r
Val = Sd->mRight[Val];\r
} else {\r
Val = Sd->mLeft[Val];\r
/**\r
Reads code lengths for the Extra Set or the Position Set.\r
\r
- @param Sd The global scratch data.\r
- @param nn Number of symbols.\r
- @param nbit Number of bits needed to represent nn.\r
+ Read in the Extra Set or Pointion Set Length Arrary, then\r
+ generate the Huffman code mapping for them.\r
+\r
+ @param Sd The global scratch data.\r
+ @param nn Number of symbols.\r
+ @param nbit Number of bits needed to represent nn.\r
@param Special The special symbol that needs to be taken care of.\r
\r
@retval 0 OK.\r
volatile UINT16 Index;\r
UINT32 Mask;\r
\r
+ //\r
+ // Read Extra Set Code Length Array size \r
+ //\r
Number = (UINT16) GetBits (Sd, nbit);\r
\r
if (Number == 0) {\r
+ //\r
+ // This represents only Huffman code used\r
+ //\r
CharC = (UINT16) GetBits (Sd, nbit);\r
\r
for (Index = 0; Index < 256; Index++) {\r
\r
CharC = (UINT16) (Sd->mBitBuf >> (BITBUFSIZ - 3));\r
\r
+ //\r
+ // If a code length is less than 7, then it is encoded as a 3-bit\r
+ // value. Or it is encoded as a series of "1"s followed by a \r
+ // terminating "0". The number of "1"s = Code length - 4.\r
+ //\r
if (CharC == 7) {\r
Mask = 1U << (BITBUFSIZ - 1 - 3);\r
while (Mask & Sd->mBitBuf) {\r
CharC += 1;\r
}\r
}\r
-\r
+ \r
FillBuf (Sd, (UINT16) ((CharC < 7) ? 3 : CharC - 3));\r
\r
Sd->mPTLen[Index++] = (UINT8) CharC;\r
-\r
+ \r
+ //\r
+ // For Code&Len Set, \r
+ // After the third length of the code length concatenation,\r
+ // a 2-bit value is used to indicated the number of consecutive \r
+ // zero lengths after the third length.\r
+ //\r
if (Index == Special) {\r
CharC = (UINT16) GetBits (Sd, 2);\r
while ((INT16) (--CharC) >= 0) {\r
while (Index < nn) {\r
Sd->mPTLen[Index++] = 0;\r
}\r
-\r
+ \r
return MakeTable (Sd, nn, Sd->mPTLen, 8, Sd->mPTTable);\r
}\r
\r
/**\r
Reads code lengths for Char&Len Set.\r
+ \r
+ Read in and decode the Char&Len Set Code Length Array, then\r
+ generate the Huffman Code mapping table for the Char&Len Set.\r
\r
@param Sd the global scratch data\r
\r
SCRATCH_DATA *Sd\r
)\r
{\r
- UINT16 Number;\r
- UINT16 CharC;\r
+ UINT16 Number;\r
+ UINT16 CharC;\r
volatile UINT16 Index;\r
- UINT32 Mask;\r
+ UINT32 Mask;\r
\r
Number = (UINT16) GetBits (Sd, CBIT);\r
\r
if (Number == 0) {\r
+ //\r
+ // This represents only Huffman code used\r
+ //\r
CharC = (UINT16) GetBits (Sd, CBIT);\r
\r
for (Index = 0; Index < NC; Index++) {\r
\r
Index = 0;\r
while (Index < Number) {\r
-\r
CharC = Sd->mPTTable[Sd->mBitBuf >> (BITBUFSIZ - 8)];\r
if (CharC >= NT) {\r
Mask = 1U << (BITBUFSIZ - 1 - 8);\r
\r
/**\r
Decode a character/length value.\r
+ \r
+ Read one value from mBitBuf, Get one code from mBitBuf. If it is at block boundary, generates\r
+ Huffman code mapping table for Extra Set, Code&Len Set and\r
+ Position Set.\r
\r
@param Sd The global scratch data.\r
\r
if (Sd->mBlockSize == 0) {\r
//\r
// Starting a new block\r
- //\r
+ // Read BlockSize from block header\r
+ // \r
Sd->mBlockSize = (UINT16) GetBits (Sd, 16);\r
+\r
+ //\r
+ // Read in the Extra Set Code Length Arrary,\r
+ // Generate the Huffman code mapping table for Extra Set.\r
+ //\r
Sd->mBadTableFlag = ReadPTLen (Sd, NT, TBIT, 3);\r
if (Sd->mBadTableFlag != 0) {\r
return 0;\r
}\r
\r
+ //\r
+ // Read in and decode the Char&Len Set Code Length Arrary,\r
+ // Generate the Huffman code mapping table for Char&Len Set.\r
+ //\r
ReadCLen (Sd);\r
\r
+ //\r
+ // Read in the Position Set Code Length Arrary, \r
+ // Generate the Huffman code mapping table for the Position Set.\r
+ //\r
Sd->mBadTableFlag = ReadPTLen (Sd, MAXNP, Sd->mPBit, (UINT16) (-1));\r
if (Sd->mBadTableFlag != 0) {\r
return 0;\r
}\r
}\r
\r
+ //\r
+ // Get one code according to Code&Set Huffman Table\r
+ //\r
Sd->mBlockSize--;\r
Index2 = Sd->mCTable[Sd->mBitBuf >> (BITBUFSIZ - 12)];\r
\r
Mask = 1U << (BITBUFSIZ - 1 - 12);\r
\r
do {\r
- if (Sd->mBitBuf & Mask) {\r
+ if ((Sd->mBitBuf & Mask) != 0) {\r
Index2 = Sd->mRight[Index2];\r
} else {\r
Index2 = Sd->mLeft[Index2];\r
\r
/**\r
Decode the source data and put the resulting data into the destination buffer.\r
-\r
+ \r
@param Sd The global scratch data\r
\r
**/\r
DataIdx = 0;\r
\r
for (;;) {\r
+ //\r
+ // Get one code from mBitBuf\r
+ // \r
CharC = DecodeC (Sd);\r
if (Sd->mBadTableFlag != 0) {\r
- return ;\r
+ goto Done;\r
}\r
\r
if (CharC < 256) {\r
// Process an Original character\r
//\r
if (Sd->mOutBuf >= Sd->mOrigSize) {\r
- return ;\r
+ goto Done;\r
} else {\r
+ //\r
+ // Write orignal character into mDstBase\r
+ //\r
Sd->mDstBase[Sd->mOutBuf++] = (UINT8) CharC;\r
}\r
\r
// Process a Pointer\r
//\r
CharC = (UINT16) (CharC - (UINT8_MAX + 1 - THRESHOLD));\r
-\r
+ \r
+ //\r
+ // Get string length\r
+ //\r
BytesRemain = CharC;\r
\r
+ //\r
+ // Locate string position\r
+ //\r
DataIdx = Sd->mOutBuf - DecodeP (Sd) - 1;\r
\r
+ //\r
+ // Write BytesRemain of bytes into mDstBase\r
+ //\r
BytesRemain--;\r
while ((INT16) (BytesRemain) >= 0) {\r
Sd->mDstBase[Sd->mOutBuf++] = Sd->mDstBase[DataIdx++];\r
if (Sd->mOutBuf >= Sd->mOrigSize) {\r
- return ;\r
+ goto Done;\r
}\r
\r
BytesRemain--;\r
}\r
}\r
\r
+Done:\r
return ;\r
}\r
\r
/**\r
- The internal implementation of *_DECOMPRESS_PROTOCOL.GetInfo().\r
-\r
- @param Source The source buffer containing the compressed data.\r
- @param SourceSize The size of source buffer\r
- @param DestinationSize The size of destination buffer.\r
- @param ScratchSize The size of scratch buffer.\r
-\r
- @retval RETURN_SUCCESS The size of destination buffer and the size of scratch buffer are successull retrieved.\r
- @retval RETURN_INVALID_PARAMETER The source data is corrupted\r
-\r
+ Given a compressed source buffer, this function retrieves the size of \r
+ the uncompressed buffer and the size of the scratch buffer required \r
+ to decompress the compressed source buffer.\r
+\r
+ Retrieves the size of the uncompressed buffer and the temporary scratch buffer \r
+ required to decompress the buffer specified by Source and SourceSize.\r
+ If the size of the uncompressed buffer or the size of the scratch buffer cannot\r
+ be determined from the compressed data specified by Source and SourceData, \r
+ then RETURN_INVALID_PARAMETER is returned. Otherwise, the size of the uncompressed\r
+ buffer is returned in DestinationSize, the size of the scratch buffer is returned\r
+ in ScratchSize, and RETURN_SUCCESS is returned.\r
+ This function does not have scratch buffer available to perform a thorough \r
+ checking of the validity of the source data. It just retrieves the "Original Size"\r
+ field from the beginning bytes of the source data and output it as DestinationSize.\r
+ And ScratchSize is specific to the decompression implementation.\r
+\r
+ If Source is NULL, then ASSERT().\r
+ If DestinationSize is NULL, then ASSERT().\r
+ If ScratchSize is NULL, then ASSERT().\r
+\r
+ @param Source The source buffer containing the compressed data.\r
+ @param SourceSize The size, in bytes, of the source buffer.\r
+ @param DestinationSize A pointer to the size, in bytes, of the uncompressed buffer\r
+ that will be generated when the compressed buffer specified\r
+ by Source and SourceSize is decompressed..\r
+ @param ScratchSize A pointer to the size, in bytes, of the scratch buffer that\r
+ is required to decompress the compressed buffer specified \r
+ by Source and SourceSize.\r
+\r
+ @retval RETURN_SUCCESS The size of the uncompressed data was returned \r
+ in DestinationSize and the size of the scratch \r
+ buffer was returned in ScratchSize.\r
+ @retval RETURN_INVALID_PARAMETER \r
+ The size of the uncompressed data or the size of \r
+ the scratch buffer cannot be determined from \r
+ the compressed data specified by Source \r
+ and SourceSize.\r
**/\r
RETURN_STATUS\r
EFIAPI\r
ASSERT (DestinationSize != NULL);\r
ASSERT (ScratchSize != NULL);\r
\r
- *ScratchSize = sizeof (SCRATCH_DATA);\r
-\r
if (SourceSize < 8) {\r
return RETURN_INVALID_PARAMETER;\r
}\r
\r
- CopyMem (&CompressedSize, Source, sizeof (UINT32));\r
- CopyMem (DestinationSize, (VOID *)((UINT8 *)Source + 4), sizeof (UINT32));\r
-\r
+ CompressedSize = ReadUnaligned32 ((UINT32 *)Source);\r
if (SourceSize < (CompressedSize + 8)) {\r
return RETURN_INVALID_PARAMETER;\r
}\r
\r
+ *ScratchSize = sizeof (SCRATCH_DATA);\r
+ *DestinationSize = ReadUnaligned32 ((UINT32 *)Source + 1);\r
+\r
return RETURN_SUCCESS;\r
}\r
\r
/**\r
- The internal implementation of *_DECOMPRESS_PROTOCOL.Decompress().\r
-\r
- @param Source The source buffer containing the compressed data.\r
+ Decompresses a compressed source buffer.\r
+\r
+ Extracts decompressed data to its original form.\r
+ This function is designed so that the decompression algorithm can be implemented\r
+ without using any memory services. As a result, this function is not allowed to\r
+ call any memory allocation services in its implementation. It is the caller's r\r
+ esponsibility to allocate and free the Destination and Scratch buffers.\r
+ If the compressed source data specified by Source is sucessfully decompressed \r
+ into Destination, then RETURN_SUCCESS is returned. If the compressed source data \r
+ specified by Source is not in a valid compressed data format,\r
+ then RETURN_INVALID_PARAMETER is returned.\r
+\r
+ If Source is NULL, then ASSERT().\r
+ If Destination is NULL, then ASSERT().\r
+ If the required scratch buffer size > 0 and Scratch is NULL, then ASSERT().\r
+\r
+ @param Source The source buffer containing the compressed data.\r
@param Destination The destination buffer to store the decompressed data\r
- @param Scratch The buffer used internally by the decompress routine. This buffer is needed to store intermediate data.\r
-\r
- @retval RETURN_SUCCESS Decompression is successfull\r
- @retval RETURN_INVALID_PARAMETER The source data is corrupted\r
-\r
+ @param Scratch A temporary scratch buffer that is used to perform the decompression.\r
+ This is an optional parameter that may be NULL if the \r
+ required scratch buffer size is 0.\r
+ \r
+ @retval RETURN_SUCCESS Decompression completed successfully, and \r
+ the uncompressed buffer is returned in Destination.\r
+ @retval RETURN_INVALID_PARAMETER \r
+ The source buffer specified by Source is corrupted \r
+ (not in a valid compressed format).\r
**/\r
RETURN_STATUS\r
EFIAPI\r
}\r
//\r
// The length of the field 'Position Set Code Length Array Size' in Block Header.\r
- // For EFI 1.1 de/compression algorithm(Version 1), mPBit = 4\r
- // For Tiano de/compression algorithm(Version 2), mPBit = 5\r
+ // For UEFI 2.0 de/compression algorithm(Version 1), mPBit = 4\r
//\r
Sd->mPBit = 4;\r
Sd->mSrcBase = (UINT8 *)Src;\r
Sd->mDstBase = Dst;\r
+ //\r
+ // CompSize and OrigSize are caculated in bytes\r
+ //\r
Sd->mCompSize = CompSize;\r
Sd->mOrigSize = OrigSize;\r
\r