(Unicode C) Decompress Large Binary File in Blocks

Decompresses a large binary file in blocks. This example uses BeginDecompressBytes, MoreDecompressBytes, and EndDecompressBytes.

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#include <C_CkFileAccessW.h>
#include <C_CkCompressionW.h>
#include <C_CkByteData.h>

void ChilkatSample(void)
    {
    HCkFileAccessW facSrc;
    HCkFileAccessW facDest;
    BOOL success;
    int blockSize;
    int numBlocks;
    HCkCompressionW compress;
    HCkByteData decompressedBytes;
    HCkByteData compressedBytes;
    int i;

    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    facSrc = CkFileAccessW_Create();
    facDest = CkFileAccessW_Create();

    // Open a previously compressed file for decompressing.
    // See Compress Large File in Blocks

    success = CkFileAccessW_OpenForRead(facSrc,L"qa_data/bmp/compressedBmp.dat");
    if (success != TRUE) {
        wprintf(L"%s\n",CkFileAccessW_lastErrorText(facSrc));
        CkFileAccessW_Dispose(facSrc);
        CkFileAccessW_Dispose(facDest);
        return;
    }

    // If we compress in 32K chunks, find out how many blocks there will be.
    blockSize = 32768;
    numBlocks = CkFileAccessW_GetNumBlocks(facSrc,blockSize);

    // Open an output file for the decompressed data.
    success = CkFileAccessW_OpenForWrite(facDest,L"qa_output/decompressed.bmp");
    if (success != TRUE) {
        wprintf(L"%s\n",CkFileAccessW_lastErrorText(facDest));
        CkFileAccessW_Dispose(facSrc);
        CkFileAccessW_Dispose(facDest);
        return;
    }

    compress = CkCompressionW_Create();
    CkCompressionW_putAlgorithm(compress,L"deflate");

    decompressedBytes = CkByteData_Create();
    compressedBytes = CkByteData_Create();

    i = 0;
    while (i < numBlocks) {
        success = CkFileAccessW_ReadBlock(facSrc,i,blockSize,compressedBytes);
        if (i == 0) {
            success = CkCompressionW_BeginDecompressBytes(compress,compressedBytes,decompressedBytes);
        }
        else {
            success = CkCompressionW_MoreDecompressBytes(compress,compressedBytes,decompressedBytes);
        }

        CkFileAccessW_FileWrite(facDest,decompressedBytes);

        i = i + 1;
    }

    // At the very end, flush any remaining decompressed bytes, if any.
    success = CkCompressionW_EndDecompressBytes(compress,decompressedBytes);
    CkFileAccessW_FileWrite(facDest,decompressedBytes);

    CkFileAccessW_FileClose(facSrc);
    CkFileAccessW_FileClose(facDest);

    wprintf(L"Finished decompressing file.\n");


    CkFileAccessW_Dispose(facSrc);
    CkFileAccessW_Dispose(facDest);
    CkCompressionW_Dispose(compress);
    CkByteData_Dispose(decompressedBytes);
    CkByteData_Dispose(compressedBytes);

    }