diff options
Diffstat (limited to 'BaseTools/Source/C/Common/EfiCompress.c')
| -rw-r--r-- | BaseTools/Source/C/Common/EfiCompress.c | 1598 |
1 files changed, 1598 insertions, 0 deletions
diff --git a/BaseTools/Source/C/Common/EfiCompress.c b/BaseTools/Source/C/Common/EfiCompress.c new file mode 100644 index 0000000000..ed491ae36d --- /dev/null +++ b/BaseTools/Source/C/Common/EfiCompress.c @@ -0,0 +1,1598 @@ +/** @file
+
+Copyright (c) 2006 - 2008, Intel Corporation. All rights reserved.<BR>
+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:
+
+ EfiCompress.c
+
+Abstract:
+
+ Compression routine. The compression algorithm is a mixture of
+ LZ77 and Huffman coding. LZ77 transforms the source data into a
+ sequence of Original Characters and Pointers to repeated strings.
+ This sequence is further divided into Blocks and Huffman codings
+ are applied to each Block.
+
+**/
+
+#include "Compress.h"
+
+
+//
+// Macro Definitions
+//
+
+#undef UINT8_MAX
+typedef INT16 NODE;
+#define UINT8_MAX 0xff
+#define UINT8_BIT 8
+#define THRESHOLD 3
+#define INIT_CRC 0
+#define WNDBIT 13
+#define WNDSIZ (1U << WNDBIT)
+#define MAXMATCH 256
+#define PERC_FLAG 0x8000U
+#define CODE_BIT 16
+#define NIL 0
+#define MAX_HASH_VAL (3 * WNDSIZ + (WNDSIZ / 512 + 1) * UINT8_MAX)
+#define HASH(p, c) ((p) + ((c) << (WNDBIT - 9)) + WNDSIZ * 2)
+#define CRCPOLY 0xA001
+#define UPDATE_CRC(c) mCrc = mCrcTable[(mCrc ^ (c)) & 0xFF] ^ (mCrc >> UINT8_BIT)
+
+//
+// C: the Char&Len Set; P: the Position Set; T: the exTra Set
+//
+
+#define NC (UINT8_MAX + MAXMATCH + 2 - THRESHOLD)
+#define CBIT 9
+#define NP (WNDBIT + 1)
+#define PBIT 4
+#define NT (CODE_BIT + 3)
+#define TBIT 5
+#if NT > NP
+ #define NPT NT
+#else
+ #define NPT NP
+#endif
+
+//
+// Function Prototypes
+//
+
+STATIC
+VOID
+PutDword(
+ IN UINT32 Data
+ );
+
+STATIC
+EFI_STATUS
+AllocateMemory (
+ );
+
+STATIC
+VOID
+FreeMemory (
+ );
+
+STATIC
+VOID
+InitSlide (
+ );
+
+STATIC
+NODE
+Child (
+ IN NODE q,
+ IN UINT8 c
+ );
+
+STATIC
+VOID
+MakeChild (
+ IN NODE q,
+ IN UINT8 c,
+ IN NODE r
+ );
+
+STATIC
+VOID
+Split (
+ IN NODE Old
+ );
+
+STATIC
+VOID
+InsertNode (
+ );
+
+STATIC
+VOID
+DeleteNode (
+ );
+
+STATIC
+VOID
+GetNextMatch (
+ );
+
+STATIC
+EFI_STATUS
+Encode (
+ );
+
+STATIC
+VOID
+CountTFreq (
+ );
+
+STATIC
+VOID
+WritePTLen (
+ IN INT32 n,
+ IN INT32 nbit,
+ IN INT32 Special
+ );
+
+STATIC
+VOID
+WriteCLen (
+ );
+
+STATIC
+VOID
+EncodeC (
+ IN INT32 c
+ );
+
+STATIC
+VOID
+EncodeP (
+ IN UINT32 p
+ );
+
+STATIC
+VOID
+SendBlock (
+ );
+
+STATIC
+VOID
+Output (
+ IN UINT32 c,
+ IN UINT32 p
+ );
+
+STATIC
+VOID
+HufEncodeStart (
+ );
+
+STATIC
+VOID
+HufEncodeEnd (
+ );
+
+STATIC
+VOID
+MakeCrcTable (
+ );
+
+STATIC
+VOID
+PutBits (
+ IN INT32 n,
+ IN UINT32 x
+ );
+
+STATIC
+INT32
+FreadCrc (
+ OUT UINT8 *p,
+ IN INT32 n
+ );
+
+STATIC
+VOID
+InitPutBits (
+ );
+
+STATIC
+VOID
+CountLen (
+ IN INT32 i
+ );
+
+STATIC
+VOID
+MakeLen (
+ IN INT32 Root
+ );
+
+STATIC
+VOID
+DownHeap (
+ IN INT32 i
+ );
+
+STATIC
+VOID
+MakeCode (
+ IN INT32 n,
+ IN UINT8 Len[],
+ OUT UINT16 Code[]
+ );
+
+STATIC
+INT32
+MakeTree (
+ IN INT32 NParm,
+ IN UINT16 FreqParm[],
+ OUT UINT8 LenParm[],
+ OUT UINT16 CodeParm[]
+ );
+
+
+//
+// Global Variables
+//
+
+STATIC UINT8 *mSrc, *mDst, *mSrcUpperLimit, *mDstUpperLimit;
+
+STATIC UINT8 *mLevel, *mText, *mChildCount, *mBuf, mCLen[NC], mPTLen[NPT], *mLen;
+STATIC INT16 mHeap[NC + 1];
+STATIC INT32 mRemainder, mMatchLen, mBitCount, mHeapSize, mN;
+STATIC UINT32 mBufSiz = 0, mOutputPos, mOutputMask, mSubBitBuf, mCrc;
+STATIC UINT32 mCompSize, mOrigSize;
+
+STATIC UINT16 *mFreq, *mSortPtr, mLenCnt[17], mLeft[2 * NC - 1], mRight[2 * NC - 1],
+ mCrcTable[UINT8_MAX + 1], mCFreq[2 * NC - 1],mCCode[NC],
+ mPFreq[2 * NP - 1], mPTCode[NPT], mTFreq[2 * NT - 1];
+
+STATIC NODE mPos, mMatchPos, mAvail, *mPosition, *mParent, *mPrev, *mNext = NULL;
+
+
+//
+// functions
+//
+
+EFI_STATUS
+EfiCompress (
+ IN UINT8 *SrcBuffer,
+ IN UINT32 SrcSize,
+ IN UINT8 *DstBuffer,
+ IN OUT UINT32 *DstSize
+ )
+/*++
+
+Routine Description:
+
+ The main compression routine.
+
+Arguments:
+
+ SrcBuffer - The buffer storing the source data
+ SrcSize - The size of source data
+ DstBuffer - The buffer to store the compressed data
+ DstSize - On input, the size of DstBuffer; On output,
+ the size of the actual compressed data.
+
+Returns:
+
+ EFI_BUFFER_TOO_SMALL - The DstBuffer is too small. In this case,
+ DstSize contains the size needed.
+ EFI_SUCCESS - Compression is successful.
+
+--*/
+{
+ EFI_STATUS Status = EFI_SUCCESS;
+
+ //
+ // Initializations
+ //
+ mBufSiz = 0;
+ mBuf = NULL;
+ mText = NULL;
+ mLevel = NULL;
+ mChildCount = NULL;
+ mPosition = NULL;
+ mParent = NULL;
+ mPrev = NULL;
+ mNext = NULL;
+
+
+ mSrc = SrcBuffer;
+ mSrcUpperLimit = mSrc + SrcSize;
+ mDst = DstBuffer;
+ mDstUpperLimit = mDst + *DstSize;
+
+ PutDword(0L);
+ PutDword(0L);
+
+ MakeCrcTable ();
+
+ mOrigSize = mCompSize = 0;
+ mCrc = INIT_CRC;
+
+ //
+ // Compress it
+ //
+
+ Status = Encode();
+ if (EFI_ERROR (Status)) {
+ return EFI_OUT_OF_RESOURCES;
+ }
+
+ //
+ // Null terminate the compressed data
+ //
+ if (mDst < mDstUpperLimit) {
+ *mDst++ = 0;
+ }
+
+ //
+ // Fill in compressed size and original size
+ //
+ mDst = DstBuffer;
+ PutDword(mCompSize+1);
+ PutDword(mOrigSize);
+
+ //
+ // Return
+ //
+
+ if (mCompSize + 1 + 8 > *DstSize) {
+ *DstSize = mCompSize + 1 + 8;
+ return EFI_BUFFER_TOO_SMALL;
+ } else {
+ *DstSize = mCompSize + 1 + 8;
+ return EFI_SUCCESS;
+ }
+
+}
+
+STATIC
+VOID
+PutDword(
+ IN UINT32 Data
+ )
+/*++
+
+Routine Description:
+
+ Put a dword to output stream
+
+Arguments:
+
+ Data - the dword to put
+
+Returns: (VOID)
+
+--*/
+{
+ if (mDst < mDstUpperLimit) {
+ *mDst++ = (UINT8)(((UINT8)(Data )) & 0xff);
+ }
+
+ if (mDst < mDstUpperLimit) {
+ *mDst++ = (UINT8)(((UINT8)(Data >> 0x08)) & 0xff);
+ }
+
+ if (mDst < mDstUpperLimit) {
+ *mDst++ = (UINT8)(((UINT8)(Data >> 0x10)) & 0xff);
+ }
+
+ if (mDst < mDstUpperLimit) {
+ *mDst++ = (UINT8)(((UINT8)(Data >> 0x18)) & 0xff);
+ }
+}
+
+STATIC
+EFI_STATUS
+AllocateMemory ()
+/*++
+
+Routine Description:
+
+ Allocate memory spaces for data structures used in compression process
+
+Argements: (VOID)
+
+Returns:
+
+ EFI_SUCCESS - Memory is allocated successfully
+ EFI_OUT_OF_RESOURCES - Allocation fails
+
+--*/
+{
+ UINT32 i;
+
+ mText = malloc (WNDSIZ * 2 + MAXMATCH);
+ for (i = 0 ; i < WNDSIZ * 2 + MAXMATCH; i ++) {
+ mText[i] = 0;
+ }
+
+ mLevel = malloc ((WNDSIZ + UINT8_MAX + 1) * sizeof(*mLevel));
+ mChildCount = malloc ((WNDSIZ + UINT8_MAX + 1) * sizeof(*mChildCount));
+ mPosition = malloc ((WNDSIZ + UINT8_MAX + 1) * sizeof(*mPosition));
+ mParent = malloc (WNDSIZ * 2 * sizeof(*mParent));
+ mPrev = malloc (WNDSIZ * 2 * sizeof(*mPrev));
+ mNext = malloc ((MAX_HASH_VAL + 1) * sizeof(*mNext));
+
+ mBufSiz = 16 * 1024U;
+ while ((mBuf = malloc(mBufSiz)) == NULL) {
+ mBufSiz = (mBufSiz / 10U) * 9U;
+ if (mBufSiz < 4 * 1024U) {
+ return EFI_OUT_OF_RESOURCES;
+ }
+ }
+ mBuf[0] = 0;
+
+ return EFI_SUCCESS;
+}
+
+VOID
+FreeMemory ()
+/*++
+
+Routine Description:
+
+ Called when compression is completed to free memory previously allocated.
+
+Arguments: (VOID)
+
+Returns: (VOID)
+
+--*/
+{
+ if (mText) {
+ free (mText);
+ }
+
+ if (mLevel) {
+ free (mLevel);
+ }
+
+ if (mChildCount) {
+ free (mChildCount);
+ }
+
+ if (mPosition) {
+ free (mPosition);
+ }
+
+ if (mParent) {
+ free (mParent);
+ }
+
+ if (mPrev) {
+ free (mPrev);
+ }
+
+ if (mNext) {
+ free (mNext);
+ }
+
+ if (mBuf) {
+ free (mBuf);
+ }
+
+ return;
+}
+
+
+STATIC
+VOID
+InitSlide ()
+/*++
+
+Routine Description:
+
+ Initialize String Info Log data structures
+
+Arguments: (VOID)
+
+Returns: (VOID)
+
+--*/
+{
+ NODE i;
+
+ for (i = WNDSIZ; i <= WNDSIZ + UINT8_MAX; i++) {
+ mLevel[i] = 1;
+ mPosition[i] = NIL; /* sentinel */
+ }
+ for (i = WNDSIZ; i < WNDSIZ * 2; i++) {
+ mParent[i] = NIL;
+ }
+ mAvail = 1;
+ for (i = 1; i < WNDSIZ - 1; i++) {
+ mNext[i] = (NODE)(i + 1);
+ }
+
+ mNext[WNDSIZ - 1] = NIL;
+ for (i = WNDSIZ * 2; i <= MAX_HASH_VAL; i++) {
+ mNext[i] = NIL;
+ }
+}
+
+
+STATIC
+NODE
+Child (
+ IN NODE q,
+ IN UINT8 c
+ )
+/*++
+
+Routine Description:
+
+ Find child node given the parent node and the edge character
+
+Arguments:
+
+ q - the parent node
+ c - the edge character
+
+Returns:
+
+ The child node (NIL if not found)
+
+--*/
+{
+ NODE r;
+
+ r = mNext[HASH(q, c)];
+ mParent[NIL] = q; /* sentinel */
+ while (mParent[r] != q) {
+ r = mNext[r];
+ }
+
+ return r;
+}
+
+STATIC
+VOID
+MakeChild (
+ IN NODE q,
+ IN UINT8 c,
+ IN NODE r
+ )
+/*++
+
+Routine Description:
+
+ Create a new child for a given parent node.
+
+Arguments:
+
+ q - the parent node
+ c - the edge character
+ r - the child node
+
+Returns: (VOID)
+
+--*/
+{
+ NODE h, t;
+
+ h = (NODE)HASH(q, c);
+ t = mNext[h];
+ mNext[h] = r;
+ mNext[r] = t;
+ mPrev[t] = r;
+ mPrev[r] = h;
+ mParent[r] = q;
+ mChildCount[q]++;
+}
+
+STATIC
+VOID
+Split (
+ NODE Old
+ )
+/*++
+
+Routine Description:
+
+ Split a node.
+
+Arguments:
+
+ Old - the node to split
+
+Returns: (VOID)
+
+--*/
+{
+ NODE New, t;
+
+ New = mAvail;
+ mAvail = mNext[New];
+ mChildCount[New] = 0;
+ t = mPrev[Old];
+ mPrev[New] = t;
+ mNext[t] = New;
+ t = mNext[Old];
+ mNext[New] = t;
+ mPrev[t] = New;
+ mParent[New] = mParent[Old];
+ mLevel[New] = (UINT8)mMatchLen;
+ mPosition[New] = mPos;
+ MakeChild(New, mText[mMatchPos + mMatchLen], Old);
+ MakeChild(New, mText[mPos + mMatchLen], mPos);
+}
+
+STATIC
+VOID
+InsertNode ()
+/*++
+
+Routine Description:
+
+ Insert string info for current position into the String Info Log
+
+Arguments: (VOID)
+
+Returns: (VOID)
+
+--*/
+{
+ NODE q, r, j, t;
+ UINT8 c, *t1, *t2;
+
+ if (mMatchLen >= 4) {
+
+ //
+ // We have just got a long match, the target tree
+ // can be located by MatchPos + 1. Travese the tree
+ // from bottom up to get to a proper starting point.
+ // The usage of PERC_FLAG ensures proper node deletion
+ // in DeleteNode() later.
+ //
+
+ mMatchLen--;
+ r = (INT16)((mMatchPos + 1) | WNDSIZ);
+ while ((q = mParent[r]) == NIL) {
+ r = mNext[r];
+ }
+ while (mLevel[q] >= mMatchLen) {
+ r = q; q = mParent[q];
+ }
+ t = q;
+ while (mPosition[t] < 0) {
+ mPosition[t] = mPos;
+ t = mParent[t];
+ }
+ if (t < WNDSIZ) {
+ mPosition[t] = (NODE)(mPos | PERC_FLAG);
+ }
+ } else {
+
+ //
+ // Locate the target tree
+ //
+
+ q = (INT16)(mText[mPos] + WNDSIZ);
+ c = mText[mPos + 1];
+ if ((r = Child(q, c)) == NIL) {
+ MakeChild(q, c, mPos);
+ mMatchLen = 1;
+ return;
+ }
+ mMatchLen = 2;
+ }
+
+ //
+ // Traverse down the tree to find a match.
+ // Update Position value along the route.
+ // Node split or creation is involved.
+ //
+
+ for ( ; ; ) {
+ if (r >= WNDSIZ) {
+ j = MAXMATCH;
+ mMatchPos = r;
+ } else {
+ j = mLevel[r];
+ mMatchPos = (NODE)(mPosition[r] & ~PERC_FLAG);
+ }
+ if (mMatchPos >= mPos) {
+ mMatchPos -= WNDSIZ;
+ }
+ t1 = &mText[mPos + mMatchLen];
+ t2 = &mText[mMatchPos + mMatchLen];
+ while (mMatchLen < j) {
+ if (*t1 != *t2) {
+ Split(r);
+ return;
+ }
+ mMatchLen++;
+ t1++;
+ t2++;
+ }
+ if (mMatchLen >= MAXMATCH) {
+ break;
+ }
+ mPosition[r] = mPos;
+ q = r;
+ if ((r = Child(q, *t1)) == NIL) {
+ MakeChild(q, *t1, mPos);
+ return;
+ }
+ mMatchLen++;
+ }
+ t = mPrev[r];
+ mPrev[mPos] = t;
+ mNext[t] = mPos;
+ t = mNext[r];
+ mNext[mPos] = t;
+ mPrev[t] = mPos;
+ mParent[mPos] = q;
+ mParent[r] = NIL;
+
+ //
+ // Special usage of 'next'
+ //
+ mNext[r] = mPos;
+
+}
+
+STATIC
+VOID
+DeleteNode ()
+/*++
+
+Routine Description:
+
+ Delete outdated string info. (The Usage of PERC_FLAG
+ ensures a clean deletion)
+
+Arguments: (VOID)
+
+Returns: (VOID)
+
+--*/
+{
+ NODE q, r, s, t, u;
+
+ if (mParent[mPos] == NIL) {
+ return;
+ }
+
+ r = mPrev[mPos];
+ s = mNext[mPos];
+ mNext[r] = s;
+ mPrev[s] = r;
+ r = mParent[mPos];
+ mParent[mPos] = NIL;
+ if (r >= WNDSIZ || --mChildCount[r] > 1) {
+ return;
+ }
+ t = (NODE)(mPosition[r] & ~PERC_FLAG);
+ if (t >= mPos) {
+ t -= WNDSIZ;
+ }
+ s = t;
+ q = mParent[r];
+ while ((u = mPosition[q]) & PERC_FLAG) {
+ u &= ~PERC_FLAG;
+ if (u >= mPos) {
+ u -= WNDSIZ;
+ }
+ if (u > s) {
+ s = u;
+ }
+ mPosition[q] = (INT16)(s | WNDSIZ);
+ q = mParent[q];
+ }
+ if (q < WNDSIZ) {
+ if (u >= mPos) {
+ u -= WNDSIZ;
+ }
+ if (u > s) {
+ s = u;
+ }
+ mPosition[q] = (INT16)(s | WNDSIZ | PERC_FLAG);
+ }
+ s = Child(r, mText[t + mLevel[r]]);
+ t = mPrev[s];
+ u = mNext[s];
+ mNext[t] = u;
+ mPrev[u] = t;
+ t = mPrev[r];
+ mNext[t] = s;
+ mPrev[s] = t;
+ t = mNext[r];
+ mPrev[t] = s;
+ mNext[s] = t;
+ mParent[s] = mParent[r];
+ mParent[r] = NIL;
+ mNext[r] = mAvail;
+ mAvail = r;
+}
+
+STATIC
+VOID
+GetNextMatch ()
+/*++
+
+Routine Description:
+
+ Advance the current position (read in new data if needed).
+ Delete outdated string info. Find a match string for current position.
+
+Arguments: (VOID)
+
+Returns: (VOID)
+
+--*/
+{
+ INT32 n;
+
+ mRemainder--;
+ if (++mPos == WNDSIZ * 2) {
+ memmove(&mText[0], &mText[WNDSIZ], WNDSIZ + MAXMATCH);
+ n = FreadCrc(&mText[WNDSIZ + MAXMATCH], WNDSIZ);
+ mRemainder += n;
+ mPos = WNDSIZ;
+ }
+ DeleteNode();
+ InsertNode();
+}
+
+STATIC
+EFI_STATUS
+Encode ()
+/*++
+
+Routine Description:
+
+ The main controlling routine for compression process.
+
+Arguments: (VOID)
+
+Returns:
+
+ EFI_SUCCESS - The compression is successful
+ EFI_OUT_0F_RESOURCES - Not enough memory for compression process
+
+--*/
+{
+ EFI_STATUS Status;
+ INT32 LastMatchLen;
+ NODE LastMatchPos;
+
+ Status = AllocateMemory();
+ if (EFI_ERROR(Status)) {
+ FreeMemory();
+ return Status;
+ }
+
+ InitSlide();
+
+ HufEncodeStart();
+
+ mRemainder = FreadCrc(&mText[WNDSIZ], WNDSIZ + MAXMATCH);
+
+ mMatchLen = 0;
+ mPos = WNDSIZ;
+ InsertNode();
+ if (mMatchLen > mRemainder) {
+ mMatchLen = mRemainder;
+ }
+ while (mRemainder > 0) {
+ LastMatchLen = mMatchLen;
+ LastMatchPos = mMatchPos;
+ GetNextMatch();
+ if (mMatchLen > mRemainder) {
+ mMatchLen = mRemainder;
+ }
+
+ if (mMatchLen > LastMatchLen || LastMatchLen < THRESHOLD) {
+
+ //
+ // Not enough benefits are gained by outputting a pointer,
+ // so just output the original character
+ //
+
+ Output(mText[mPos - 1], 0);
+ } else {
+
+ //
+ // Outputting a pointer is beneficial enough, do it.
+ //
+
+ Output(LastMatchLen + (UINT8_MAX + 1 - THRESHOLD),
+ (mPos - LastMatchPos - 2) & (WNDSIZ - 1));
+ while (--LastMatchLen > 0) {
+ GetNextMatch();
+ }
+ if (mMatchLen > mRemainder) {
+ mMatchLen = mRemainder;
+ }
+ }
+ }
+
+ HufEncodeEnd();
+ FreeMemory();
+ return EFI_SUCCESS;
+}
+
+STATIC
+VOID
+CountTFreq ()
+/*++
+
+Routine Description:
+
+ Count the frequencies for the Extra Set
+
+Arguments: (VOID)
+
+Returns: (VOID)
+
+--*/
+{
+ INT32 i, k, n, Count;
+
+ for (i = 0; i < NT; i++) {
+ mTFreq[i] = 0;
+ }
+ n = NC;
+ while (n > 0 && mCLen[n - 1] == 0) {
+ n--;
+ }
+ i = 0;
+ while (i < n) {
+ k = mCLen[i++];
+ if (k == 0) {
+ Count = 1;
+ while (i < n && mCLen[i] == 0) {
+ i++;
+ Count++;
+ }
+ if (Count <= 2) {
+ mTFreq[0] = (UINT16)(mTFreq[0] + Count);
+ } else if (Count <= 18) {
+ mTFreq[1]++;
+ } else if (Count == 19) {
+ mTFreq[0]++;
+ mTFreq[1]++;
+ } else {
+ mTFreq[2]++;
+ }
+ } else {
+ mTFreq[k + 2]++;
+ }
+ }
+}
+
+STATIC
+VOID
+WritePTLen (
+ IN INT32 n,
+ IN INT32 nbit,
+ IN INT32 Special
+ )
+/*++
+
+Routine Description:
+
+ Outputs the code length array for the Extra Set or the Position Set.
+
+Arguments:
+
+ n - the number of symbols
+ nbit - the number of bits needed to represent 'n'
+ Special - the special symbol that needs to be take care of
+
+Returns: (VOID)
+
+--*/
+{
+ INT32 i, k;
+
+ while (n > 0 && mPTLen[n - 1] == 0) {
+ n--;
+ }
+ PutBits(nbit, n);
+ i = 0;
+ while (i < n) {
+ k = mPTLen[i++];
+ if (k <= 6) {
+ PutBits(3, k);
+ } else {
+ PutBits(k - 3, (1U << (k - 3)) - 2);
+ }
+ if (i == Special) {
+ while (i < 6 && mPTLen[i] == 0) {
+ i++;
+ }
+ PutBits(2, (i - 3) & 3);
+ }
+ }
+}
+
+STATIC
+VOID
+WriteCLen ()
+/*++
+
+Routine Description:
+
+ Outputs the code length array for Char&Length Set
+
+Arguments: (VOID)
+
+Returns: (VOID)
+
+--*/
+{
+ INT32 i, k, n, Count;
+
+ n = NC;
+ while (n > 0 && mCLen[n - 1] == 0) {
+ n--;
+ }
+ PutBits(CBIT, n);
+ i = 0;
+ while (i < n) {
+ k = mCLen[i++];
+ if (k == 0) {
+ Count = 1;
+ while (i < n && mCLen[i] == 0) {
+ i++;
+ Count++;
+ }
+ if (Count <= 2) {
+ for (k = 0; k < Count; k++) {
+ PutBits(mPTLen[0], mPTCode[0]);
+ }
+ } else if (Count <= 18) {
+ PutBits(mPTLen[1], mPTCode[1]);
+ PutBits(4, Count - 3);
+ } else if (Count == 19) {
+ PutBits(mPTLen[0], mPTCode[0]);
+ PutBits(mPTLen[1], mPTCode[1]);
+ PutBits(4, 15);
+ } else {
+ PutBits(mPTLen[2], mPTCode[2]);
+ PutBits(CBIT, Count - 20);
+ }
+ } else {
+ PutBits(mPTLen[k + 2], mPTCode[k + 2]);
+ }
+ }
+}
+
+STATIC
+VOID
+EncodeC (
+ IN INT32 c
+ )
+{
+ PutBits(mCLen[c], mCCode[c]);
+}
+
+STATIC
+VOID
+EncodeP (
+ IN UINT32 p
+ )
+{
+ UINT32 c, q;
+
+ c = 0;
+ q = p;
+ while (q) {
+ q >>= 1;
+ c++;
+ }
+ PutBits(mPTLen[c], mPTCode[c]);
+ if (c > 1) {
+ PutBits(c - 1, p & (0xFFFFU >> (17 - c)));
+ }
+}
+
+STATIC
+VOID
+SendBlock ()
+/*++
+
+Routine Description:
+
+ Huffman code the block and output it.
+
+Argument: (VOID)
+
+Returns: (VOID)
+
+--*/
+{
+ UINT32 i, k, Flags, Root, Pos, Size;
+ Flags = 0;
+
+ Root = MakeTree(NC, mCFreq, mCLen, mCCode);
+ Size = mCFreq[Root];
+ PutBits(16, Size);
+ if (Root >= NC) {
+ CountTFreq();
+ Root = MakeTree(NT, mTFreq, mPTLen, mPTCode);
+ if (Root >= NT) {
+ WritePTLen(NT, TBIT, 3);
+ } else {
+ PutBits(TBIT, 0);
+ PutBits(TBIT, Root);
+ }
+ WriteCLen();
+ } else {
+ PutBits(TBIT, 0);
+ PutBits(TBIT, 0);
+ PutBits(CBIT, 0);
+ PutBits(CBIT, Root);
+ }
+ Root = MakeTree(NP, mPFreq, mPTLen, mPTCode);
+ if (Root >= NP) {
+ WritePTLen(NP, PBIT, -1);
+ } else {
+ PutBits(PBIT, 0);
+ PutBits(PBIT, Root);
+ }
+ Pos = 0;
+ for (i = 0; i < Size; i++) {
+ if (i % UINT8_BIT == 0) {
+ Flags = mBuf[Pos++];
+ } else {
+ Flags <<= 1;
+ }
+ if (Flags & (1U << (UINT8_BIT - 1))) {
+ EncodeC(mBuf[Pos++] + (1U << UINT8_BIT));
+ k = mBuf[Pos++] << UINT8_BIT;
+ k += mBuf[Pos++];
+ EncodeP(k);
+ } else {
+ EncodeC(mBuf[Pos++]);
+ }
+ }
+ for (i = 0; i < NC; i++) {
+ mCFreq[i] = 0;
+ }
+ for (i = 0; i < NP; i++) {
+ mPFreq[i] = 0;
+ }
+}
+
+
+STATIC
+VOID
+Output (
+ IN UINT32 c,
+ IN UINT32 p
+ )
+/*++
+
+Routine Description:
+
+ Outputs an Original Character or a Pointer
+
+Arguments:
+
+ c - The original character or the 'String Length' element of a Pointer
+ p - The 'Position' field of a Pointer
+
+Returns: (VOID)
+
+--*/
+{
+ STATIC UINT32 CPos;
+
+ if ((mOutputMask >>= 1) == 0) {
+ mOutputMask = 1U << (UINT8_BIT - 1);
+ if (mOutputPos >= mBufSiz - 3 * UINT8_BIT) {
+ SendBlock();
+ mOutputPos = 0;
+ }
+ CPos = mOutputPos++;
+ mBuf[CPos] = 0;
+ }
+ mBuf[mOutputPos++] = (UINT8) c;
+ mCFreq[c]++;
+ if (c >= (1U << UINT8_BIT)) {
+ mBuf[CPos] |= mOutputMask;
+ mBuf[mOutputPos++] = (UINT8)(p >> UINT8_BIT);
+ mBuf[mOutputPos++] = (UINT8) p;
+ c = 0;
+ while (p) {
+ p >>= 1;
+ c++;
+ }
+ mPFreq[c]++;
+ }
+}
+
+STATIC
+VOID
+HufEncodeStart ()
+{
+ INT32 i;
+
+ for (i = 0; i < NC; i++) {
+ mCFreq[i] = 0;
+ }
+ for (i = 0; i < NP; i++) {
+ mPFreq[i] = 0;
+ }
+ mOutputPos = mOutputMask = 0;
+ InitPutBits();
+ return;
+}
+
+STATIC
+VOID
+HufEncodeEnd ()
+{
+ SendBlock();
+
+ //
+ // Flush remaining bits
+ //
+ PutBits(UINT8_BIT - 1, 0);
+
+ return;
+}
+
+
+STATIC
+VOID
+MakeCrcTable ()
+{
+ UINT32 i, j, r;
+
+ for (i = 0; i <= UINT8_MAX; i++) {
+ r = i;
+ for (j = 0; j < UINT8_BIT; j++) {
+ if (r & 1) {
+ r = (r >> 1) ^ CRCPOLY;
+ } else {
+ r >>= 1;
+ }
+ }
+ mCrcTable[i] = (UINT16)r;
+ }
+}
+
+STATIC
+VOID
+PutBits (
+ IN INT32 n,
+ IN UINT32 x
+ )
+/*++
+
+Routine Description:
+
+ Outputs rightmost n bits of x
+
+Argments:
+
+ n - the rightmost n bits of the data is used
+ x - the data
+
+Returns: (VOID)
+
+--*/
+{
+ UINT8 Temp;
+
+ if (n < mBitCount) {
+ mSubBitBuf |= x << (mBitCount -= n);
+ } else {
+
+ Temp = (UINT8)(mSubBitBuf | (x >> (n -= mBitCount)));
+ if (mDst < mDstUpperLimit) {
+ *mDst++ = Temp;
+ }
+ mCompSize++;
+
+ if (n < UINT8_BIT) {
+ mSubBitBuf = x << (mBitCount = UINT8_BIT - n);
+ } else {
+
+ Temp = (UINT8)(x >> (n - UINT8_BIT));
+ if (mDst < mDstUpperLimit) {
+ *mDst++ = Temp;
+ }
+ mCompSize++;
+
+ mSubBitBuf = x << (mBitCount = 2 * UINT8_BIT - n);
+ }
+ }
+}
+
+STATIC
+INT32
+FreadCrc (
+ OUT UINT8 *p,
+ IN INT32 n
+ )
+/*++
+
+Routine Description:
+
+ Read in source data
+
+Arguments:
+
+ p - the buffer to hold the data
+ n - number of bytes to read
+
+Returns:
+
+ number of bytes actually read
+
+--*/
+{
+ INT32 i;
+
+ for (i = 0; mSrc < mSrcUpperLimit && i < n; i++) {
+ *p++ = *mSrc++;
+ }
+ n = i;
+
+ p -= n;
+ mOrigSize += n;
+ while (--i >= 0) {
+ UPDATE_CRC(*p++);
+ }
+ return n;
+}
+
+
+STATIC
+VOID
+InitPutBits ()
+{
+ mBitCount = UINT8_BIT;
+ mSubBitBuf = 0;
+}
+
+STATIC
+VOID
+CountLen (
+ IN INT32 i
+ )
+/*++
+
+Routine Description:
+
+ Count the number of each code length for a Huffman tree.
+
+Arguments:
+
+ i - the top node
+
+Returns: (VOID)
+
+--*/
+{
+ STATIC INT32 Depth = 0;
+
+ if (i < mN) {
+ mLenCnt[(Depth < 16) ? Depth : 16]++;
+ } else {
+ Depth++;
+ CountLen(mLeft [i]);
+ CountLen(mRight[i]);
+ Depth--;
+ }
+}
+
+STATIC
+VOID
+MakeLen (
+ IN INT32 Root
+ )
+/*++
+
+Routine Description:
+
+ Create code length array for a Huffman tree
+
+Arguments:
+
+ Root - the root of the tree
+
+--*/
+{
+ INT32 i, k;
+ UINT32 Cum;
+
+ for (i = 0; i <= 16; i++) {
+ mLenCnt[i] = 0;
+ }
+ CountLen(Root);
+
+ //
+ // Adjust the length count array so that
+ // no code will be generated longer than its designated length
+ //
+
+ Cum = 0;
+ for (i = 16; i > 0; i--) {
+ Cum += mLenCnt[i] << (16 - i);
+ }
+ while (Cum != (1U << 16)) {
+ mLenCnt[16]--;
+ for (i = 15; i > 0; i--) {
+ if (mLenCnt[i] != 0) {
+ mLenCnt[i]--;
+ mLenCnt[i+1] += 2;
+ break;
+ }
+ }
+ Cum--;
+ }
+ for (i = 16; i > 0; i--) {
+ k = mLenCnt[i];
+ while (--k >= 0) {
+ mLen[*mSortPtr++] = (UINT8)i;
+ }
+ }
+}
+
+STATIC
+VOID
+DownHeap (
+ IN INT32 i
+ )
+{
+ INT32 j, k;
+
+ //
+ // priority queue: send i-th entry down heap
+ //
+
+ k = mHeap[i];
+ while ((j = 2 * i) <= mHeapSize) {
+ if (j < mHeapSize && mFreq[mHeap[j]] > mFreq[mHeap[j + 1]]) {
+ j++;
+ }
+ if (mFreq[k] <= mFreq[mHeap[j]]) {
+ break;
+ }
+ mHeap[i] = mHeap[j];
+ i = j;
+ }
+ mHeap[i] = (INT16)k;
+}
+
+STATIC
+VOID
+MakeCode (
+ IN INT32 n,
+ IN UINT8 Len[],
+ OUT UINT16 Code[]
+ )
+/*++
+
+Routine Description:
+
+ Assign code to each symbol based on the code length array
+
+Arguments:
+
+ n - number of symbols
+ Len - the code length array
+ Code - stores codes for each symbol
+
+Returns: (VOID)
+
+--*/
+{
+ INT32 i;
+ UINT16 Start[18];
+
+ Start[1] = 0;
+ for (i = 1; i <= 16; i++) {
+ Start[i + 1] = (UINT16)((Start[i] + mLenCnt[i]) << 1);
+ }
+ for (i = 0; i < n; i++) {
+ Code[i] = Start[Len[i]]++;
+ }
+}
+
+STATIC
+INT32
+MakeTree (
+ IN INT32 NParm,
+ IN UINT16 FreqParm[],
+ OUT UINT8 LenParm[],
+ OUT UINT16 CodeParm[]
+ )
+/*++
+
+Routine Description:
+
+ Generates Huffman codes given a frequency distribution of symbols
+
+Arguments:
+
+ NParm - number of symbols
+ FreqParm - frequency of each symbol
+ LenParm - code length for each symbol
+ CodeParm - code for each symbol
+
+Returns:
+
+ Root of the Huffman tree.
+
+--*/
+{
+ INT32 i, j, k, Avail;
+
+ //
+ // make tree, calculate len[], return root
+ //
+
+ mN = NParm;
+ mFreq = FreqParm;
+ mLen = LenParm;
+ Avail = mN;
+ mHeapSize = 0;
+ mHeap[1] = 0;
+ for (i = 0; i < mN; i++) {
+ mLen[i] = 0;
+ if (mFreq[i]) {
+ mHeap[++mHeapSize] = (INT16)i;
+ }
+ }
+ if (mHeapSize < 2) {
+ CodeParm[mHeap[1]] = 0;
+ return mHeap[1];
+ }
+ for (i = mHeapSize / 2; i >= 1; i--) {
+
+ //
+ // make priority queue
+ //
+ DownHeap(i);
+ }
+ mSortPtr = CodeParm;
+ do {
+ i = mHeap[1];
+ if (i < mN) {
+ *mSortPtr++ = (UINT16)i;
+ }
+ mHeap[1] = mHeap[mHeapSize--];
+ DownHeap(1);
+ j = mHeap[1];
+ if (j < mN) {
+ *mSortPtr++ = (UINT16)j;
+ }
+ k = Avail++;
+ mFreq[k] = (UINT16)(mFreq[i] + mFreq[j]);
+ mHeap[1] = (INT16)k;
+ DownHeap(1);
+ mLeft[k] = (UINT16)i;
+ mRight[k] = (UINT16)j;
+ } while (mHeapSize > 1);
+
+ mSortPtr = CodeParm;
+ MakeLen(k);
+ MakeCode(NParm, LenParm, CodeParm);
+
+ //
+ // return root
+ //
+ return k;
+}
+
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