1 files changed, 319 insertions, 0 deletions
diff --git a/contrib/zstd/zbuff_compress.c b/contrib/zstd/zbuff_compress.c
new file mode 100644
index 000000000..5095b43e6
--- /dev/null
+++ b/contrib/zstd/zbuff_compress.c
@@ -0,0 +1,319 @@
+/**
+ * Copyright (c) 2016-present, Yann Collet, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+
+
+
+/* *************************************
+*  Dependencies
+***************************************/
+#include <stdlib.h>
+#include "error_private.h"
+#include "zstd_internal.h"  /* MIN, ZSTD_BLOCKHEADERSIZE, defaultCustomMem */
+#define ZBUFF_STATIC_LINKING_ONLY
+#include "zbuff.h"
+
+
+/* *************************************
+*  Constants
+***************************************/
+static size_t const ZBUFF_endFrameSize = ZSTD_BLOCKHEADERSIZE;
+
+
+/*-***********************************************************
+*  Streaming compression
+*
+*  A ZBUFF_CCtx object is required to track streaming operation.
+*  Use ZBUFF_createCCtx() and ZBUFF_freeCCtx() to create/release resources.
+*  Use ZBUFF_compressInit() to start a new compression operation.
+*  ZBUFF_CCtx objects can be reused multiple times.
+*
+*  Use ZBUFF_compressContinue() repetitively to consume your input.
+*  *srcSizePtr and *dstCapacityPtr can be any size.
+*  The function will report how many bytes were read or written by modifying *srcSizePtr and *dstCapacityPtr.
+*  Note that it may not consume the entire input, in which case it's up to the caller to call again the function with remaining input.
+*  The content of dst will be overwritten (up to *dstCapacityPtr) at each function call, so save its content if it matters or change dst .
+*  @return : a hint to preferred nb of bytes to use as input for next function call (it's only a hint, to improve latency)
+*            or an error code, which can be tested using ZBUFF_isError().
+*
+*  ZBUFF_compressFlush() can be used to instruct ZBUFF to compress and output whatever remains within its buffer.
+*  Note that it will not output more than *dstCapacityPtr.
+*  Therefore, some content might still be left into its internal buffer if dst buffer is too small.
+*  @return : nb of bytes still present into internal buffer (0 if it's empty)
+*            or an error code, which can be tested using ZBUFF_isError().
+*
+*  ZBUFF_compressEnd() instructs to finish a frame.
+*  It will perform a flush and write frame epilogue.
+*  Similar to ZBUFF_compressFlush(), it may not be able to output the entire internal buffer content if *dstCapacityPtr is too small.
+*  @return : nb of bytes still present into internal buffer (0 if it's empty)
+*            or an error code, which can be tested using ZBUFF_isError().
+*
+*  Hint : recommended buffer sizes (not compulsory)
+*  input : ZSTD_BLOCKSIZE_MAX (128 KB), internal unit size, it improves latency to use this value.
+*  output : ZSTD_compressBound(ZSTD_BLOCKSIZE_MAX) + ZSTD_blockHeaderSize + ZBUFF_endFrameSize : ensures it's always possible to write/flush/end a full block at best speed.
+* ***********************************************************/
+
+typedef enum { ZBUFFcs_init, ZBUFFcs_load, ZBUFFcs_flush, ZBUFFcs_final } ZBUFF_cStage;
+
+/* *** Resources *** */
+struct ZBUFF_CCtx_s {
+    ZSTD_CCtx* zc;
+    char*  inBuff;
+    size_t inBuffSize;
+    size_t inToCompress;
+    size_t inBuffPos;
+    size_t inBuffTarget;
+    size_t blockSize;
+    char*  outBuff;
+    size_t outBuffSize;
+    size_t outBuffContentSize;
+    size_t outBuffFlushedSize;
+    ZBUFF_cStage stage;
+    U32    checksum;
+    U32    frameEnded;
+    ZSTD_customMem customMem;
+};   /* typedef'd tp ZBUFF_CCtx within "zbuff.h" */
+
+ZBUFF_CCtx* ZBUFF_createCCtx(void)
+{
+    return ZBUFF_createCCtx_advanced(defaultCustomMem);
+}
+
+ZBUFF_CCtx* ZBUFF_createCCtx_advanced(ZSTD_customMem customMem)
+{
+    ZBUFF_CCtx* zbc;
+
+    if (!customMem.customAlloc && !customMem.customFree)
+        customMem = defaultCustomMem;
+
+    if (!customMem.customAlloc || !customMem.customFree)
+        return NULL;
+
+    zbc = (ZBUFF_CCtx*)customMem.customAlloc(customMem.opaque, sizeof(ZBUFF_CCtx));
+    if (zbc==NULL) return NULL;
+    memset(zbc, 0, sizeof(ZBUFF_CCtx));
+    memcpy(&zbc->customMem, &customMem, sizeof(ZSTD_customMem));
+    zbc->zc = ZSTD_createCCtx_advanced(customMem);
+    if (zbc->zc == NULL) { ZBUFF_freeCCtx(zbc); return NULL; }
+    return zbc;
+}
+
+size_t ZBUFF_freeCCtx(ZBUFF_CCtx* zbc)
+{
+    if (zbc==NULL) return 0;   /* support free on NULL */
+    ZSTD_freeCCtx(zbc->zc);
+    if (zbc->inBuff) zbc->customMem.customFree(zbc->customMem.opaque, zbc->inBuff);
+    if (zbc->outBuff) zbc->customMem.customFree(zbc->customMem.opaque, zbc->outBuff);
+    zbc->customMem.customFree(zbc->customMem.opaque, zbc);
+    return 0;
+}
+
+
+/* ======   Initialization   ====== */
+
+size_t ZBUFF_compressInit_advanced(ZBUFF_CCtx* zbc,
+                                   const void* dict, size_t dictSize,
+                                   ZSTD_parameters params, unsigned long long pledgedSrcSize)
+{
+    /* allocate buffers */
+    {   size_t const neededInBuffSize = (size_t)1 << params.cParams.windowLog;
+        if (zbc->inBuffSize < neededInBuffSize) {
+            zbc->inBuffSize = neededInBuffSize;
+            zbc->customMem.customFree(zbc->customMem.opaque, zbc->inBuff);   /* should not be necessary */
+            zbc->inBuff = (char*)zbc->customMem.customAlloc(zbc->customMem.opaque, neededInBuffSize);
+            if (zbc->inBuff == NULL) return ERROR(memory_allocation);
+        }
+        zbc->blockSize = MIN(ZSTD_BLOCKSIZE_ABSOLUTEMAX, neededInBuffSize);
+    }
+    if (zbc->outBuffSize < ZSTD_compressBound(zbc->blockSize)+1) {
+        zbc->outBuffSize = ZSTD_compressBound(zbc->blockSize)+1;
+        zbc->customMem.customFree(zbc->customMem.opaque, zbc->outBuff);   /* should not be necessary */
+        zbc->outBuff = (char*)zbc->customMem.customAlloc(zbc->customMem.opaque, zbc->outBuffSize);
+        if (zbc->outBuff == NULL) return ERROR(memory_allocation);
+    }
+
+    { size_t const errorCode = ZSTD_compressBegin_advanced(zbc->zc, dict, dictSize, params, pledgedSrcSize);
+      if (ZSTD_isError(errorCode)) return errorCode; }
+
+    zbc->inToCompress = 0;
+    zbc->inBuffPos = 0;
+    zbc->inBuffTarget = zbc->blockSize;
+    zbc->outBuffContentSize = zbc->outBuffFlushedSize = 0;
+    zbc->stage = ZBUFFcs_load;
+    zbc->checksum = params.fParams.checksumFlag > 0;
+    zbc->frameEnded = 0;
+    return 0;   /* ready to go */
+}
+
+
+size_t ZBUFF_compressInitDictionary(ZBUFF_CCtx* zbc, const void* dict, size_t dictSize, int compressionLevel)
+{
+    ZSTD_parameters const params = ZSTD_getParams(compressionLevel, 0, dictSize);
+    return ZBUFF_compressInit_advanced(zbc, dict, dictSize, params, 0);
+}
+
+size_t ZBUFF_compressInit(ZBUFF_CCtx* zbc, int compressionLevel)
+{
+    return ZBUFF_compressInitDictionary(zbc, NULL, 0, compressionLevel);
+}
+
+
+/* internal util function */
+MEM_STATIC size_t ZBUFF_limitCopy(void* dst, size_t dstCapacity, const void* src, size_t srcSize)
+{
+    size_t const length = MIN(dstCapacity, srcSize);
+    memcpy(dst, src, length);
+    return length;
+}
+
+
+/* ======   Compression   ====== */
+
+typedef enum { zbf_gather, zbf_flush, zbf_end } ZBUFF_flush_e;
+
+static size_t ZBUFF_compressContinue_generic(ZBUFF_CCtx* zbc,
+                              void* dst, size_t* dstCapacityPtr,
+                        const void* src, size_t* srcSizePtr,
+                              ZBUFF_flush_e const flush)
+{
+    U32 someMoreWork = 1;
+    const char* const istart = (const char*)src;
+    const char* const iend = istart + *srcSizePtr;
+    const char* ip = istart;
+    char* const ostart = (char*)dst;
+    char* const oend = ostart + *dstCapacityPtr;
+    char* op = ostart;
+
+    while (someMoreWork) {
+        switch(zbc->stage)
+        {
+        case ZBUFFcs_init: return ERROR(init_missing);   /* call ZBUFF_compressInit() first ! */
+
+        case ZBUFFcs_load:
+            /* complete inBuffer */
+            {   size_t const toLoad = zbc->inBuffTarget - zbc->inBuffPos;
+                size_t const loaded = ZBUFF_limitCopy(zbc->inBuff + zbc->inBuffPos, toLoad, ip, iend-ip);
+                zbc->inBuffPos += loaded;
+                ip += loaded;
+                if ( (zbc->inBuffPos==zbc->inToCompress) || (!flush && (toLoad != loaded)) ) {
+                    someMoreWork = 0; break;  /* not enough input to get a full block : stop there, wait for more */
+            }   }
+            /* compress current block (note : this stage cannot be stopped in the middle) */
+            {   void* cDst;
+                size_t cSize;
+                size_t const iSize = zbc->inBuffPos - zbc->inToCompress;
+                size_t oSize = oend-op;
+                if (oSize >= ZSTD_compressBound(iSize))
+                    cDst = op;   /* compress directly into output buffer (avoid flush stage) */
+                else
+                    cDst = zbc->outBuff, oSize = zbc->outBuffSize;
+                cSize = (flush == zbf_end) ?
+                        ZSTD_compressEnd(zbc->zc, cDst, oSize, zbc->inBuff + zbc->inToCompress, iSize) :
+                        ZSTD_compressContinue(zbc->zc, cDst, oSize, zbc->inBuff + zbc->inToCompress, iSize);
+                if (ZSTD_isError(cSize)) return cSize;
+                if (flush == zbf_end) zbc->frameEnded = 1;
+                /* prepare next block */
+                zbc->inBuffTarget = zbc->inBuffPos + zbc->blockSize;
+                if (zbc->inBuffTarget > zbc->inBuffSize)
+                    zbc->inBuffPos = 0, zbc->inBuffTarget = zbc->blockSize;   /* note : inBuffSize >= blockSize */
+                zbc->inToCompress = zbc->inBuffPos;
+                if (cDst == op) { op += cSize; break; }   /* no need to flush */
+                zbc->outBuffContentSize = cSize;
+                zbc->outBuffFlushedSize = 0;
+                zbc->stage = ZBUFFcs_flush;   /* continue to flush stage */
+            }
+
+        case ZBUFFcs_flush:
+            {   size_t const toFlush = zbc->outBuffContentSize - zbc->outBuffFlushedSize;
+                size_t const flushed = ZBUFF_limitCopy(op, oend-op, zbc->outBuff + zbc->outBuffFlushedSize, toFlush);
+                op += flushed;
+                zbc->outBuffFlushedSize += flushed;
+                if (toFlush!=flushed) { someMoreWork = 0; break; } /* dst too small to store flushed data : stop there */
+                zbc->outBuffContentSize = zbc->outBuffFlushedSize = 0;
+                zbc->stage = ZBUFFcs_load;
+                break;
+            }
+
+        case ZBUFFcs_final:
+            someMoreWork = 0;   /* do nothing */
+            break;
+
+        default:
+            return ERROR(GENERIC);   /* impossible */
+        }
+    }
+
+    *srcSizePtr = ip - istart;
+    *dstCapacityPtr = op - ostart;
+    if (zbc->frameEnded) return 0;
+    {   size_t hintInSize = zbc->inBuffTarget - zbc->inBuffPos;
+        if (hintInSize==0) hintInSize = zbc->blockSize;
+        return hintInSize;
+    }
+}
+
+size_t ZBUFF_compressContinue(ZBUFF_CCtx* zbc,
+                              void* dst, size_t* dstCapacityPtr,
+                        const void* src, size_t* srcSizePtr)
+{
+    return ZBUFF_compressContinue_generic(zbc, dst, dstCapacityPtr, src, srcSizePtr, zbf_gather);
+}
+
+
+
+/* ======   Finalize   ====== */
+
+size_t ZBUFF_compressFlush(ZBUFF_CCtx* zbc, void* dst, size_t* dstCapacityPtr)
+{
+    size_t srcSize = 0;
+    ZBUFF_compressContinue_generic(zbc, dst, dstCapacityPtr, &srcSize, &srcSize, zbf_flush);  /* use a valid src address instead of NULL */
+    return zbc->outBuffContentSize - zbc->outBuffFlushedSize;
+}
+
+
+size_t ZBUFF_compressEnd(ZBUFF_CCtx* zbc, void* dst, size_t* dstCapacityPtr)
+{
+    BYTE* const ostart = (BYTE*)dst;
+    BYTE* const oend = ostart + *dstCapacityPtr;
+    BYTE* op = ostart;
+
+    if (zbc->stage != ZBUFFcs_final) {
+        /* flush whatever remains */
+        size_t outSize = *dstCapacityPtr;
+        size_t srcSize = 0;
+        size_t const notEnded = ZBUFF_compressContinue_generic(zbc, dst, &outSize, &srcSize, &srcSize, zbf_end);  /* use a valid address instead of NULL */
+        size_t const remainingToFlush = zbc->outBuffContentSize - zbc->outBuffFlushedSize;
+        op += outSize;
+        if (remainingToFlush) {
+            *dstCapacityPtr = op-ostart;
+            return remainingToFlush + ZBUFF_endFrameSize + (zbc->checksum * 4);
+        }
+        /* create epilogue */
+        zbc->stage = ZBUFFcs_final;
+        zbc->outBuffContentSize = !notEnded ? 0 :
+            ZSTD_compressEnd(zbc->zc, zbc->outBuff, zbc->outBuffSize, NULL, 0);  /* write epilogue into outBuff */
+    }
+
+    /* flush epilogue */
+    {   size_t const toFlush = zbc->outBuffContentSize - zbc->outBuffFlushedSize;
+        size_t const flushed = ZBUFF_limitCopy(op, oend-op, zbc->outBuff + zbc->outBuffFlushedSize, toFlush);
+        op += flushed;
+        zbc->outBuffFlushedSize += flushed;
+        *dstCapacityPtr = op-ostart;
+        if (toFlush==flushed) zbc->stage = ZBUFFcs_init;  /* end reached */
+        return toFlush - flushed;
+    }
+}
+
+
+
+/* *************************************
+*  Tool functions
+***************************************/
+size_t ZBUFF_recommendedCInSize(void)  { return ZSTD_BLOCKSIZE_ABSOLUTEMAX; }
+size_t ZBUFF_recommendedCOutSize(void) { return ZSTD_compressBound(ZSTD_BLOCKSIZE_ABSOLUTEMAX) + ZSTD_blockHeaderSize + ZBUFF_endFrameSize; }