cpp-ch/local-engine/IO/SplittableBzip2ReadBuffer.h

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#pragma once

#include "config.h"

#if USE_BZIP2
#include <vector>
#include <IO/CompressedReadBufferWrapper.h>
#include <base/StringRef.h>
#include <iostream>

namespace DB
{

class BZip2Constants
{
public:
    static constexpr Int32 BASE_BLOCK_SIZE = 100000;
    static constexpr Int32 MAX_ALPHA_SIZE = 258;
    static constexpr Int32 MAX_CODE_LEN = 23;
    static constexpr Int32 RUNA = 0;
    static constexpr Int32 RUNB = 1;
    static constexpr Int32 N_GROUPS = 6;
    static constexpr Int32 G_SIZE = 50;
    static constexpr Int32 N_ITERS = 4;
    static constexpr Int32 MAX_SELECTORS = (2 + (900000 / G_SIZE));
    static constexpr Int32 NUM_OVERSHOOT_BYTES = 20;
    static constexpr Int32 END_OF_BLOCK = -2;
    static constexpr Int32 END_OF_STREAM = -1;
    static constexpr Int32 rNums[]
        = {619, 720, 127, 481, 931, 816, 813, 233, 566, 247, 985, 724, 205, 454, 863, 491, 741, 242, 949, 214, 733, 859, 335, 708, 621, 574,
           73,  654, 730, 472, 419, 436, 278, 496, 867, 210, 399, 680, 480, 51,  878, 465, 811, 169, 869, 675, 611, 697, 867, 561, 862, 687,
           507, 283, 482, 129, 807, 591, 733, 623, 150, 238, 59,  379, 684, 877, 625, 169, 643, 105, 170, 607, 520, 932, 727, 476, 693, 425,
           174, 647, 73,  122, 335, 530, 442, 853, 695, 249, 445, 515, 909, 545, 703, 919, 874, 474, 882, 500, 594, 612, 641, 801, 220, 162,
           819, 984, 589, 513, 495, 799, 161, 604, 958, 533, 221, 400, 386, 867, 600, 782, 382, 596, 414, 171, 516, 375, 682, 485, 911, 276,
           98,  553, 163, 354, 666, 933, 424, 341, 533, 870, 227, 730, 475, 186, 263, 647, 537, 686, 600, 224, 469, 68,  770, 919, 190, 373,
           294, 822, 808, 206, 184, 943, 795, 384, 383, 461, 404, 758, 839, 887, 715, 67,  618, 276, 204, 918, 873, 777, 604, 560, 951, 160,
           578, 722, 79,  804, 96,  409, 713, 940, 652, 934, 970, 447, 318, 353, 859, 672, 112, 785, 645, 863, 803, 350, 139, 93,  354, 99,
           820, 908, 609, 772, 154, 274, 580, 184, 79,  626, 630, 742, 653, 282, 762, 623, 680, 81,  927, 626, 789, 125, 411, 521, 938, 300,
           821, 78,  343, 175, 128, 250, 170, 774, 972, 275, 999, 639, 495, 78,  352, 126, 857, 956, 358, 619, 580, 124, 737, 594, 701, 612,
           669, 112, 134, 694, 363, 992, 809, 743, 168, 974, 944, 375, 748, 52,  600, 747, 642, 182, 862, 81,  344, 805, 988, 739, 511, 655,
           814, 334, 249, 515, 897, 955, 664, 981, 649, 113, 974, 459, 893, 228, 433, 837, 553, 268, 926, 240, 102, 654, 459, 51,  686, 754,
           806, 760, 493, 403, 415, 394, 687, 700, 946, 670, 656, 610, 738, 392, 760, 799, 887, 653, 978, 321, 576, 617, 626, 502, 894, 679,
           243, 440, 680, 879, 194, 572, 640, 724, 926, 56,  204, 700, 707, 151, 457, 449, 797, 195, 791, 558, 945, 679, 297, 59,  87,  824,
           713, 663, 412, 693, 342, 606, 134, 108, 571, 364, 631, 212, 174, 643, 304, 329, 343, 97,  430, 751, 497, 314, 983, 374, 822, 928,
           140, 206, 73,  263, 980, 736, 876, 478, 430, 305, 170, 514, 364, 692, 829, 82,  855, 953, 676, 246, 369, 970, 294, 750, 807, 827,
           150, 790, 288, 923, 804, 378, 215, 828, 592, 281, 565, 555, 710, 82,  896, 831, 547, 261, 524, 462, 293, 465, 502, 56,  661, 821,
           976, 991, 658, 869, 905, 758, 745, 193, 768, 550, 608, 933, 378, 286, 215, 979, 792, 961, 61,  688, 793, 644, 986, 403, 106, 366,
           905, 644, 372, 567, 466, 434, 645, 210, 389, 550, 919, 135, 780, 773, 635, 389, 707, 100, 626, 958, 165, 504, 920, 176, 193, 713,
           857, 265, 203, 50,  668, 108, 645, 990, 626, 197, 510, 357, 358, 850, 858, 364, 936, 638};
};


class SplittableBzip2ReadBuffer : public CompressedReadBufferWrapper
{
public:
    static constexpr Int64 BLOCK_DELIMITER = 0X314159265359L;
    static constexpr Int64 EOS_DELIMITER = 0X177245385090L;
    static constexpr Int32 DELIMITER_BIT_LENGTH = 48;

private:
    struct Data
    {
        bool inUse[256] = {false};

        char seqToUnseq[256] = {0};
        char selector[BZip2Constants::MAX_SELECTORS] = {0};
        char selectorMtf[BZip2Constants::MAX_SELECTORS] = {0};

        Int32 unzftab[256] = {0};

        Int32 limit[BZip2Constants::N_GROUPS][BZip2Constants::MAX_ALPHA_SIZE] = {{0}};
        Int32 base[BZip2Constants::N_GROUPS][BZip2Constants::MAX_ALPHA_SIZE] = {{0}};
        Int32 perm[BZip2Constants::N_GROUPS][BZip2Constants::MAX_ALPHA_SIZE] = {{0}};
        Int32 minLens[BZip2Constants::N_GROUPS] = {0};

        Int32 cftab[257] = {0};
        UInt16 getAndMoveToFrontDecode_yy[256] = {0};
        UInt16 temp_charArray2d[BZip2Constants::N_GROUPS][BZip2Constants::MAX_ALPHA_SIZE] = {{0}};

        char recvDecodingTables_pos[BZip2Constants::N_GROUPS] = {0};

        std::vector<Int32> tt;
        std::vector<char> ll8;

        explicit Data(Int32 blockSize100k_) : ll8(blockSize100k_ * BZip2Constants::BASE_BLOCK_SIZE) { }

        std::vector<Int32> & initTT(Int32 length);
        std::string toString();

    private:
        /// Helper static functions for toString()
        template <typename T>
        static std::string arrayToString(const std::vector<T> & arr);
        template <typename T>
        static std::string array2DToString(T arr[BZip2Constants::N_GROUPS][BZip2Constants::MAX_ALPHA_SIZE]);
        template <typename T>
        static std::string arrayToString(const T * arr, size_t size);
    };

    class CRC
    {
    public:
        static constexpr UInt32 crc32Table[]
            = {0x00000000, 0x04c11db7, 0x09823b6e, 0x0d4326d9, 0x130476dc, 0x17c56b6b, 0x1a864db2, 0x1e475005, 0x2608edb8, 0x22c9f00f,
               0x2f8ad6d6, 0x2b4bcb61, 0x350c9b64, 0x31cd86d3, 0x3c8ea00a, 0x384fbdbd, 0x4c11db70, 0x48d0c6c7, 0x4593e01e, 0x4152fda9,
               0x5f15adac, 0x5bd4b01b, 0x569796c2, 0x52568b75, 0x6a1936c8, 0x6ed82b7f, 0x639b0da6, 0x675a1011, 0x791d4014, 0x7ddc5da3,
               0x709f7b7a, 0x745e66cd, 0x9823b6e0, 0x9ce2ab57, 0x91a18d8e, 0x95609039, 0x8b27c03c, 0x8fe6dd8b, 0x82a5fb52, 0x8664e6e5,
               0xbe2b5b58, 0xbaea46ef, 0xb7a96036, 0xb3687d81, 0xad2f2d84, 0xa9ee3033, 0xa4ad16ea, 0xa06c0b5d, 0xd4326d90, 0xd0f37027,
               0xddb056fe, 0xd9714b49, 0xc7361b4c, 0xc3f706fb, 0xceb42022, 0xca753d95, 0xf23a8028, 0xf6fb9d9f, 0xfbb8bb46, 0xff79a6f1,
               0xe13ef6f4, 0xe5ffeb43, 0xe8bccd9a, 0xec7dd02d, 0x34867077, 0x30476dc0, 0x3d044b19, 0x39c556ae, 0x278206ab, 0x23431b1c,
               0x2e003dc5, 0x2ac12072, 0x128e9dcf, 0x164f8078, 0x1b0ca6a1, 0x1fcdbb16, 0x018aeb13, 0x054bf6a4, 0x0808d07d, 0x0cc9cdca,
               0x7897ab07, 0x7c56b6b0, 0x71159069, 0x75d48dde, 0x6b93dddb, 0x6f52c06c, 0x6211e6b5, 0x66d0fb02, 0x5e9f46bf, 0x5a5e5b08,
               0x571d7dd1, 0x53dc6066, 0x4d9b3063, 0x495a2dd4, 0x44190b0d, 0x40d816ba, 0xaca5c697, 0xa864db20, 0xa527fdf9, 0xa1e6e04e,
               0xbfa1b04b, 0xbb60adfc, 0xb6238b25, 0xb2e29692, 0x8aad2b2f, 0x8e6c3698, 0x832f1041, 0x87ee0df6, 0x99a95df3, 0x9d684044,
               0x902b669d, 0x94ea7b2a, 0xe0b41de7, 0xe4750050, 0xe9362689, 0xedf73b3e, 0xf3b06b3b, 0xf771768c, 0xfa325055, 0xfef34de2,
               0xc6bcf05f, 0xc27dede8, 0xcf3ecb31, 0xcbffd686, 0xd5b88683, 0xd1799b34, 0xdc3abded, 0xd8fba05a, 0x690ce0ee, 0x6dcdfd59,
               0x608edb80, 0x644fc637, 0x7a089632, 0x7ec98b85, 0x738aad5c, 0x774bb0eb, 0x4f040d56, 0x4bc510e1, 0x46863638, 0x42472b8f,
               0x5c007b8a, 0x58c1663d, 0x558240e4, 0x51435d53, 0x251d3b9e, 0x21dc2629, 0x2c9f00f0, 0x285e1d47, 0x36194d42, 0x32d850f5,
               0x3f9b762c, 0x3b5a6b9b, 0x0315d626, 0x07d4cb91, 0x0a97ed48, 0x0e56f0ff, 0x1011a0fa, 0x14d0bd4d, 0x19939b94, 0x1d528623,
               0xf12f560e, 0xf5ee4bb9, 0xf8ad6d60, 0xfc6c70d7, 0xe22b20d2, 0xe6ea3d65, 0xeba91bbc, 0xef68060b, 0xd727bbb6, 0xd3e6a601,
               0xdea580d8, 0xda649d6f, 0xc423cd6a, 0xc0e2d0dd, 0xcda1f604, 0xc960ebb3, 0xbd3e8d7e, 0xb9ff90c9, 0xb4bcb610, 0xb07daba7,
               0xae3afba2, 0xaafbe615, 0xa7b8c0cc, 0xa379dd7b, 0x9b3660c6, 0x9ff77d71, 0x92b45ba8, 0x9675461f, 0x8832161a, 0x8cf30bad,
               0x81b02d74, 0x857130c3, 0x5d8a9099, 0x594b8d2e, 0x5408abf7, 0x50c9b640, 0x4e8ee645, 0x4a4ffbf2, 0x470cdd2b, 0x43cdc09c,
               0x7b827d21, 0x7f436096, 0x7200464f, 0x76c15bf8, 0x68860bfd, 0x6c47164a, 0x61043093, 0x65c52d24, 0x119b4be9, 0x155a565e,
               0x18197087, 0x1cd86d30, 0x029f3d35, 0x065e2082, 0x0b1d065b, 0x0fdc1bec, 0x3793a651, 0x3352bbe6, 0x3e119d3f, 0x3ad08088,
               0x2497d08d, 0x2056cd3a, 0x2d15ebe3, 0x29d4f654, 0xc5a92679, 0xc1683bce, 0xcc2b1d17, 0xc8ea00a0, 0xd6ad50a5, 0xd26c4d12,
               0xdf2f6bcb, 0xdbee767c, 0xe3a1cbc1, 0xe760d676, 0xea23f0af, 0xeee2ed18, 0xf0a5bd1d, 0xf464a0aa, 0xf9278673, 0xfde69bc4,
               0x89b8fd09, 0x8d79e0be, 0x803ac667, 0x84fbdbd0, 0x9abc8bd5, 0x9e7d9662, 0x933eb0bb, 0x97ffad0c, 0xafb010b1, 0xab710d06,
               0xa6322bdf, 0xa2f33668, 0xbcb4666d, 0xb8757bda, 0xb5365d03, 0xb1f740b4};

        CRC() { initialiseCRC(); }
        ~CRC() = default;

        void initialiseCRC() { globalCrc = 0xffffffff; }
        Int32 getFinalCRC() const { return ~globalCrc; }
        Int32 getGlobalCRC() const { return globalCrc; }
        void setGlobalCRC(Int32 newCrc) { globalCrc = newCrc; }
        void updateCRC(Int32 inCh)
        {
            Int32 temp = (globalCrc >> 24) ^ inCh;
            if (temp < 0)
                temp = 256 + temp;
            globalCrc = (globalCrc << 8) ^ static_cast<Int32>(crc32Table[temp]);
            // std::cout << "input:" << inCh << " crc:" << globalCrc << std::endl;
        }
        void updateCRC(Int32 inCh, Int32 repeat)
        {
            Int32 globalCrcShadow = globalCrc;
            while (repeat-- > 0)
            {
                Int32 temp = (globalCrcShadow >> 24) ^ inCh;
                globalCrcShadow = (globalCrcShadow << 8) ^ static_cast<Int32>(crc32Table[(temp >= 0) ? temp : (temp + 256)]);
            }
            globalCrc = globalCrcShadow;
        }

    private:
        Int32 globalCrc;
    };

    enum class STATE : int8_t
    {
        END_OF_FILE = 0,
        START_BLOCK_STATE,
        RAND_PART_A_STATE,
        RAND_PART_B_STATE,
        RAND_PART_C_STATE,
        NO_RAND_PART_A_STATE,
        NO_RAND_PART_B_STATE,
        NO_RAND_PART_C_STATE,
        NO_PROCESS_STATE
    };

    /// If current bzip2 file split is not the fist one, then start_need_special_process should be true.
    /// When it is true, the decompressed result of the first block will be ignored except the last line.
    /// Case1:
    /// e.g. "line1 \n line2 \n line3", line1 and line2 will be ignored because they are processed in the previous split.
    /// We are not sure if line3 is a completed line, so line3 will be concated before the decompressed result of the next block in current split.
    /// Case2:
    /// e.g. "line2 \n line2 \n line3 \n", all lines will be ignored because they are processed in the previous split.
    const bool first_block_need_special_process;

    /// If current bzip2 file split is not the last one, then end_need_special_process should be true.
    /// When it is true, the decompressed result of the last block will be processed except the last line.
    /// Case1:
    /// e.g. "line1 \n line2 \n line3", line3 will be ignored because it is processed in the next split.
    /// Case2:
    /// e.g. "line1 \n line2 \n line3 \n", all lines will be processed because we are pretty sure that line3 is a completed line.
    const bool last_block_need_special_process;

    /// Whether the compressed block is the first one. It is used to apply special process for the first block.
    bool is_first_block;

    /// Record the last incomplete line in the latest `nextImpl`
    /// It is excluded from the output of latest `nextImpl` because we are not sure if it is completed in the lifetime of the current split until next `nextImpl`.
    String last_incomplete_line;


    Int32 blockSize100k;
    STATE currentState;
    bool skipResult;
    Int32 currentChar;
    Int32 storedBlockCRC;
    bool blockRandomised;
    std::unique_ptr<Data> data;
    CRC crc;
    Int32 computedBlockCRC;
    Int32 storedCombinedCRC;
    Int32 computedCombinedCRC;

    Int32 origPtr;
    Int32 nInUse;
    Int64 bsBuff;
    Int64 bsLive;
    Int32 last;

    Int32 su_count;
    Int32 su_ch2;
    Int32 su_chPrev;
    Int32 su_i2;
    Int32 su_j2;
    Int32 su_rNToGo;
    Int32 su_rTPos;
    Int32 su_tPos;
    UInt16 su_z;

    /// SplittableBzip2ReadBuffer will skip bytes before the first block header. adjusted_start records file position after skipping.
    /// It is only valid when input stream is seekable and block header could be found in input stream.
    std::optional<size_t> adjusted_start;

    static void hbCreateDecodeTables(
        Int32 * __restrict limit,
        Int32 * __restrict base,
        Int32 * __restrict perm,
        const UInt16 * __restrict length,
        Int32 minLen,
        Int32 maxLen,
        Int32 alphaSize);

public:
    explicit SplittableBzip2ReadBuffer(
        std::unique_ptr<ReadBuffer> in_,
        bool first_block_need_special_process_ = false,
        bool last_block_need_special_process_ = false,
        size_t buf_size = DBMS_DEFAULT_BUFFER_SIZE,
        char * existing_memory = nullptr,
        size_t alignment = 0);

    ~SplittableBzip2ReadBuffer() override = default;

    std::optional<size_t> getAdjustedStart() const { return adjusted_start; }

    bool nextImpl() override;

    static bool skipToNextMarker(Int64 marker, Int32 markerBitLength, ReadBuffer & in_, Int64 & bsBuff_, Int64 & bsLive_);

private:
    Int32 read(char * dest, size_t dest_size, size_t offs, size_t len);
    Int32 read0();
    static Int32 readAByte(ReadBuffer & in_);

    bool skipToNextMarker(Int64 marker, Int32 markerBitLength);

    [[noreturn]] void reportCRCError();

    void makeMaps();

    void changeStateToProcessABlock();

    void initBlock();

    void endBlock();

    void complete();

    static Int64 bsR(Int64 n, ReadBuffer & in_, Int64 & bsBuff_, Int64 & bsLive_);
    Int64 bsR(Int64 n);
    bool bsGetBit();
    char bsGetUByte() { return bsR(8); }
    Int32 bsGetInt() { return static_cast<Int32>((((((bsR(8) << 8) | bsR(8)) << 8) | bsR(8)) << 8) | bsR(8)); }

    void recvDecodingTables();

    void createHuffmanDecodingTables(Int32 alphaSize, Int32 nGroups);

    void getAndMoveToFrontDecode();
    Int32 getAndMoveToFrontDecode0(Int32 groupNo);

    void setupBlock();
    void setupRandPartA();
    void setupNoRandPartA();
    void setupRandPartB();
    void setupRandPartC();
    void setupNoRandPartB();
    void setupNoRandPartC();
};

}
#endif