tsdbReadImpl.c

/*
 * Copyright (c) 2019 TAOS Data, Inc. <jhtao@taosdata.com>
 *
 * This program is free software: you can use, redistribute, and/or modify
 * it under the terms of the GNU Affero General Public License, version 3
 * or later ("AGPL"), as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */

#include "tsdb.h"

#define TSDB_KEY_COL_OFFSET 0

static void tsdbResetReadTable(SReadH *pReadh);
static void tsdbResetReadFile(SReadH *pReadh);
static int  tsdbLoadBlockOffset(SReadH *pReadh, SBlock *pBlock);
static int  tsdbLoadBlockDataImpl(SReadH *pReadh, SBlock *pBlock, SDataCols *pDataCols, int8_t bitmapMode);
static int  tsdbCheckAndDecodeColumnData(SDataCol *pDataCol, void *content, int32_t len, int32_t bitmapLen, int8_t comp,
                                         int numOfRows, int numOfBitmaps, int maxPoints, char *buffer, int bufferSize);
static int  tsdbLoadBlockDataColsImpl(SReadH *pReadh, SBlock *pBlock, SDataCols *pDataCols, const int16_t *colIds,
                                      int numOfColIds, int8_t bitmapMode);
static int  tsdbLoadColData(SReadH *pReadh, SDFile *pDFile, SBlock *pBlock, SBlockCol *pBlockCol, SDataCol *pDataCol);

int tsdbInitReadH(SReadH *pReadh, STsdb *pRepo) {
  ASSERT(pReadh != NULL && pRepo != NULL);

  STsdbCfg *pCfg = REPO_CFG(pRepo);

  memset((void *)pReadh, 0, sizeof(*pReadh));
  pReadh->pRepo = pRepo;

  TSDB_FSET_SET_CLOSED(TSDB_READ_FSET(pReadh));

  pReadh->aBlkIdx = taosArrayInit(1024, sizeof(SBlockIdx));
  if (pReadh->aBlkIdx == NULL) {
    terrno = TSDB_CODE_TDB_OUT_OF_MEMORY;
    return -1;
  }

  pReadh->pDCols[0] = tdNewDataCols(0, pCfg->maxRows);
  if (pReadh->pDCols[0] == NULL) {
    terrno = TSDB_CODE_TDB_OUT_OF_MEMORY;
    tsdbDestroyReadH(pReadh);
    return -1;
  }

  pReadh->pDCols[1] = tdNewDataCols(0, pCfg->maxRows);
  if (pReadh->pDCols[1] == NULL) {
    terrno = TSDB_CODE_TDB_OUT_OF_MEMORY;
    tsdbDestroyReadH(pReadh);
    return -1;
  }

  return 0;
}

void tsdbDestroyReadH(SReadH *pReadh) {
  if (pReadh == NULL) return;

  pReadh->pExBuf = taosTZfree(pReadh->pExBuf);
  pReadh->pCBuf = taosTZfree(pReadh->pCBuf);
  pReadh->pBuf = taosTZfree(pReadh->pBuf);
  pReadh->pDCols[0] = tdFreeDataCols(pReadh->pDCols[0]);
  pReadh->pDCols[1] = tdFreeDataCols(pReadh->pDCols[1]);
  pReadh->pAggrBlkData = taosTZfree(pReadh->pAggrBlkData);
  pReadh->pBlkData = taosTZfree(pReadh->pBlkData);
  pReadh->pBlkInfo = taosTZfree(pReadh->pBlkInfo);
  pReadh->cidx = 0;
  pReadh->pBlkIdx = NULL;
  pReadh->pTable = NULL;
  pReadh->aBlkIdx = taosArrayDestroy(pReadh->aBlkIdx);
  tsdbCloseDFileSet(TSDB_READ_FSET(pReadh));
  pReadh->pRepo = NULL;
}

int tsdbSetAndOpenReadFSet(SReadH *pReadh, SDFileSet *pSet) {
  ASSERT(pSet != NULL);
  tsdbResetReadFile(pReadh);

  pReadh->rSet = *pSet;
  TSDB_FSET_SET_CLOSED(TSDB_READ_FSET(pReadh));
  // if (tsdbOpenDFileSet(TSDB_READ_FSET(pReadh), O_RDONLY) < 0) {
  if (tsdbOpenDFileSet(TSDB_READ_FSET(pReadh), TD_FILE_READ) < 0) {
    tsdbError("vgId:%d, failed to open file set %d since %s", TSDB_READ_REPO_ID(pReadh), TSDB_FSET_FID(pSet),
              tstrerror(terrno));
    return -1;
  }

  return 0;
}

void tsdbCloseAndUnsetFSet(SReadH *pReadh) { tsdbResetReadFile(pReadh); }

int tsdbLoadBlockIdx(SReadH *pReadh) {
  SDFile   *pHeadf = TSDB_READ_HEAD_FILE(pReadh);
  SBlockIdx blkIdx;

  ASSERT(taosArrayGetSize(pReadh->aBlkIdx) == 0);

  // No data at all, just return
  if (pHeadf->info.offset <= 0) return 0;

  if (tsdbSeekDFile(pHeadf, pHeadf->info.offset, SEEK_SET) < 0) {
    tsdbError("vgId:%d, failed to load SBlockIdx part while seek file %s since %s, offset:%u len :%u",
              TSDB_READ_REPO_ID(pReadh), TSDB_FILE_FULL_NAME(pHeadf), tstrerror(terrno), pHeadf->info.offset,
              pHeadf->info.len);
    return -1;
  }

  if (tsdbMakeRoom((void **)(&TSDB_READ_BUF(pReadh)), pHeadf->info.len) < 0) return -1;

  int64_t nread = tsdbReadDFile(pHeadf, TSDB_READ_BUF(pReadh), pHeadf->info.len);
  if (nread < 0) {
    tsdbError("vgId:%d, failed to load SBlockIdx part while read file %s since %s, offset:%u len :%u",
              TSDB_READ_REPO_ID(pReadh), TSDB_FILE_FULL_NAME(pHeadf), tstrerror(terrno), pHeadf->info.offset,
              pHeadf->info.len);
    return -1;
  }

  if (nread < pHeadf->info.len) {
    terrno = TSDB_CODE_TDB_FILE_CORRUPTED;
    tsdbError("vgId:%d, SBlockIdx part in file %s is corrupted, offset:%u expected bytes:%u read bytes: %" PRId64,
              TSDB_READ_REPO_ID(pReadh), TSDB_FILE_FULL_NAME(pHeadf), pHeadf->info.offset, pHeadf->info.len, nread);
    return -1;
  }

  if (!taosCheckChecksumWhole((uint8_t *)TSDB_READ_BUF(pReadh), pHeadf->info.len)) {
    terrno = TSDB_CODE_TDB_FILE_CORRUPTED;
    tsdbError("vgId:%d, SBlockIdx part in file %s is corrupted since wrong checksum, offset:%u len :%u",
              TSDB_READ_REPO_ID(pReadh), TSDB_FILE_FULL_NAME(pHeadf), pHeadf->info.offset, pHeadf->info.len);
    return -1;
  }

  void *ptr = TSDB_READ_BUF(pReadh);
  int   tsize = 0;
  while (POINTER_DISTANCE(ptr, TSDB_READ_BUF(pReadh)) < (pHeadf->info.len - sizeof(TSCKSUM))) {
    ptr = tsdbDecodeSBlockIdx(ptr, &blkIdx);
    ASSERT(ptr != NULL);

    if (taosArrayPush(pReadh->aBlkIdx, (void *)(&blkIdx)) == NULL) {
      terrno = TSDB_CODE_TDB_OUT_OF_MEMORY;
      return -1;
    }

    tsize++;
    // ASSERT(tsize == 1 || ((SBlockIdx *)taosArrayGet(pReadh->aBlkIdx, tsize - 2))->tid <
    //                          ((SBlockIdx *)taosArrayGet(pReadh->aBlkIdx, tsize - 1))->tid);
  }

  return 0;
}

int tsdbSetReadTable(SReadH *pReadh, STable *pTable) {
  STSchema *pSchema = tsdbGetTableSchemaImpl(TSDB_READ_REPO(pReadh), pTable, false, false, -1);

  pReadh->pTable = pTable;

  if (tdInitDataCols(pReadh->pDCols[0], pSchema) < 0) {
    terrno = TSDB_CODE_TDB_OUT_OF_MEMORY;
    return -1;
  }

  if (tdInitDataCols(pReadh->pDCols[1], pSchema) < 0) {
    terrno = TSDB_CODE_TDB_OUT_OF_MEMORY;
    return -1;
  }

  size_t size = taosArrayGetSize(pReadh->aBlkIdx);
  if (size > 0) {
    while (true) {
      if (pReadh->cidx >= size) {
        pReadh->pBlkIdx = NULL;
        break;
      }

      SBlockIdx *pBlkIdx = taosArrayGet(pReadh->aBlkIdx, pReadh->cidx);
      if (pBlkIdx->uid == TABLE_TID(pTable)) {
        if (pBlkIdx->uid == TABLE_UID(pTable)) {
          pReadh->pBlkIdx = pBlkIdx;
        } else {
          pReadh->pBlkIdx = NULL;
        }
        pReadh->cidx++;
        break;
      } else if (pBlkIdx->uid > TABLE_TID(pTable)) {
        pReadh->pBlkIdx = NULL;
        break;
      } else {
        pReadh->cidx++;
      }
    }
  } else {
    pReadh->pBlkIdx = NULL;
  }

  return 0;
}

int tsdbLoadBlockInfo(SReadH *pReadh, void *pTarget) {
  ASSERT(pReadh->pBlkIdx != NULL);

  SDFile    *pHeadf = TSDB_READ_HEAD_FILE(pReadh);
  SBlockIdx *pBlkIdx = pReadh->pBlkIdx;

  if (tsdbSeekDFile(pHeadf, pBlkIdx->offset, SEEK_SET) < 0) {
    tsdbError("vgId:%d, failed to load SBlockInfo part while seek file %s since %s, offset:%u len:%u",
              TSDB_READ_REPO_ID(pReadh), TSDB_FILE_FULL_NAME(pHeadf), tstrerror(terrno), pBlkIdx->offset, pBlkIdx->len);
    return -1;
  }

  if (tsdbMakeRoom((void **)(&(pReadh->pBlkInfo)), pBlkIdx->len) < 0) return -1;

  int64_t nread = tsdbReadDFile(pHeadf, (void *)(pReadh->pBlkInfo), pBlkIdx->len);
  if (nread < 0) {
    tsdbError("vgId:%d, failed to load SBlockInfo part while read file %s since %s, offset:%u len :%u",
              TSDB_READ_REPO_ID(pReadh), TSDB_FILE_FULL_NAME(pHeadf), tstrerror(terrno), pBlkIdx->offset, pBlkIdx->len);
    return -1;
  }

  if (nread < pBlkIdx->len) {
    terrno = TSDB_CODE_TDB_FILE_CORRUPTED;
    tsdbError("vgId:%d, SBlockInfo part in file %s is corrupted, offset:%u expected bytes:%u read bytes:%" PRId64,
              TSDB_READ_REPO_ID(pReadh), TSDB_FILE_FULL_NAME(pHeadf), pBlkIdx->offset, pBlkIdx->len, nread);
    return -1;
  }

  if (!taosCheckChecksumWhole((uint8_t *)(pReadh->pBlkInfo), pBlkIdx->len)) {
    terrno = TSDB_CODE_TDB_FILE_CORRUPTED;
    tsdbError("vgId:%d, SBlockInfo part in file %s is corrupted since wrong checksum, offset:%u len :%u",
              TSDB_READ_REPO_ID(pReadh), TSDB_FILE_FULL_NAME(pHeadf), pBlkIdx->offset, pBlkIdx->len);
    return -1;
  }

  // ASSERT(pBlkIdx->tid == pReadh->pBlkInfo->tid && pBlkIdx->uid == pReadh->pBlkInfo->uid);

  if (pTarget) {
    memcpy(pTarget, (void *)(pReadh->pBlkInfo), pBlkIdx->len);
  }

  return 0;
}

static FORCE_INLINE void tsdbSwapDataCols(SDataCols *pDest, SDataCols *pSrc) {
  SDataCol *pCols = pDest->cols;
  memcpy(pDest, pSrc, sizeof(SDataCols));
  pSrc->cols = pCols;
}

static void printTsdbLoadBlkData(SReadH *readh, SDataCols *pDCols, SBlock *pBlock, const char *tag, int32_t ln) {
  printf("%s:%d:%" PRIi64 " ================\n", tag, ln, taosGetSelfPthreadId());
  if (pBlock) {
    SDFile *pHeadf = TSDB_READ_HEAD_FILE(readh);
    printf("%s:%d:%" PRIi64 ":%p:%d %s\n", tag, ln, taosGetSelfPthreadId(), pBlock, (int32_t)pBlock->len,
           pHeadf->f.aname);
    SDFile *pDFile = pBlock->last ? TSDB_READ_LAST_FILE(readh) : TSDB_READ_DATA_FILE(readh);
    printf("%s:%d:%" PRIi64 ":%p:%d %s\n", tag, ln, taosGetSelfPthreadId(), pBlock, (int32_t)pBlock->len,
           pDFile->f.aname);
  }
  SDataCol *pDCol = pDCols->cols + 0;
  if (TSKEY_MIN == *(int64_t *)pDCol->pData) {
    ASSERT(0);
  }

  int rows = pDCols->numOfRows;
  for (int r = 0; r < rows; ++r) {
    if (pBlock) {
      printf("%s:%d:%" PRIi64 ":%p:%d rows[%d][%d] ", tag, ln, taosGetSelfPthreadId(), pBlock, (int32_t)pBlock->len,
             rows, r);
    } else {
      printf("%s:%d:%" PRIi64 ":%s rows[%d][%d] ", tag, ln, taosGetSelfPthreadId(), "=== merge === ", rows, r);
    }

    int      nDataCols = pDCols->numOfCols;
    int      j = 0;
    SCellVal sVal = {0};
    while (j < nDataCols) {
      SDataCol *pDataCol = pDCols->cols + j;
      tdGetColDataOfRow(&sVal, pDataCol, r, pDCols->bitmapMode);
      tdSCellValPrint(&sVal, pDataCol->type);
      ++j;
    }
    printf("\n");
  }

  fflush(stdout);
}

int tsdbLoadBlockData(SReadH *pReadh, SBlock *pBlock, SBlockInfo *pBlkInfo) {
  ASSERT(pBlock->numOfSubBlocks > 0);
  STsdbCfg *pCfg = REPO_CFG(pReadh->pRepo);
  int8_t    update = pCfg->update;

  SBlock *iBlock = pBlock;
  if (pBlock->numOfSubBlocks > 1) {
    if (pBlkInfo) {
      iBlock = (SBlock *)POINTER_SHIFT(pBlkInfo, pBlock->offset);
    } else {
      iBlock = (SBlock *)POINTER_SHIFT(pReadh->pBlkInfo, pBlock->offset);
    }
  }

  if (tsdbLoadBlockDataImpl(pReadh, iBlock, pReadh->pDCols[0], TSDB_BITMODE_ONE_BIT) < 0) return -1;
#ifdef TD_DEBUG_PRINT_TSDB_LOAD_DCOLS
  printTsdbLoadBlkData(pReadh, pReadh->pDCols[0], iBlock, __func__, __LINE__);
#endif
  for (int i = 1; i < pBlock->numOfSubBlocks; i++) {
    iBlock++;
    if (tsdbLoadBlockDataImpl(pReadh, iBlock, pReadh->pDCols[1], TSDB_BITMODE_DEFAULT) < 0) return -1;
#ifdef TD_DEBUG_PRINT_TSDB_LOAD_DCOLS
    printTsdbLoadBlkData(pReadh, pReadh->pDCols[1], iBlock, __func__, __LINE__);
#endif
    // TODO: use the real maxVersion to replace the UINT64_MAX to support Multi-Version
    if (tdMergeDataCols(pReadh->pDCols[0], pReadh->pDCols[1], pReadh->pDCols[1]->numOfRows, NULL,
                        TD_SUPPORT_UPDATE(update), TD_VER_MAX) < 0)
      return -1;
#ifdef TD_DEBUG_PRINT_TSDB_LOAD_DCOLS
    printTsdbLoadBlkData(pReadh, pReadh->pDCols[0], iBlock, " === MERGE === ", __LINE__);
#endif
  }
  // if ((pBlock->numOfSubBlocks == 1) && (iBlock->hasDupKey)) { // TODO: use this line
  if (pBlock->numOfSubBlocks == 1) {
    tdResetDataCols(pReadh->pDCols[1]);
    pReadh->pDCols[1]->bitmapMode = pReadh->pDCols[0]->bitmapMode;
    if (tdMergeDataCols(pReadh->pDCols[1], pReadh->pDCols[0], pReadh->pDCols[0]->numOfRows, NULL,
                        TD_SUPPORT_UPDATE(update), TD_VER_MAX) < 0) {
      return -1;
    }
    tsdbSwapDataCols(pReadh->pDCols[0], pReadh->pDCols[1]);
    ASSERT(pReadh->pDCols[0]->bitmapMode != 0);
#ifdef TD_DEBUG_PRINT_TSDB_LOAD_DCOLS
    printTsdbLoadBlkData(pReadh, pReadh->pDCols[0], iBlock, " === UPDATE FILTER === ", __LINE__);
#endif
  }

  ASSERT(pReadh->pDCols[0]->numOfRows <= pBlock->numOfRows);
  ASSERT(dataColsKeyFirst(pReadh->pDCols[0]) == pBlock->minKey.ts);
  ASSERT(dataColsKeyLast(pReadh->pDCols[0]) == pBlock->maxKey.ts);

  return 0;
}

static void printTsdbLoadBlkDataCols(SReadH *readh, SDataCols *pDCols, SBlock *pBlock, const int16_t *colIds,
                                     int numOfColsIds, const char *tag, int32_t ln) {
  printf("%s:%d:%" PRIi64 " ================\n", tag, ln, taosGetSelfPthreadId());
  if (pBlock) {
    SDFile *pHeadf = TSDB_READ_HEAD_FILE(readh);
    printf("%s:%d:%" PRIi64 ":%p:%d %s\n", tag, ln, taosGetSelfPthreadId(), pBlock, (int32_t)pBlock->len,
           pHeadf->f.aname);
    SDFile *pDFile = pBlock->last ? TSDB_READ_LAST_FILE(readh) : TSDB_READ_DATA_FILE(readh);
    printf("%s:%d:%" PRIi64 ":%p:%d %s\n", tag, ln, taosGetSelfPthreadId(), pBlock, (int32_t)pBlock->len,
           pDFile->f.aname);
  }

  int rows = pDCols->numOfRows;
  for (int r = 0; r < rows; ++r) {
    if (pBlock) {
      printf("%s:%d:%" PRIi64 ":%p:%d  rows[%d][%d] ", tag, ln, taosGetSelfPthreadId(), pBlock, (int32_t)pBlock->len,
             rows, r);
    } else {
      printf("%s:%d:%" PRIi64 ":%s rows[%d][%d] ", tag, ln, taosGetSelfPthreadId(), "=== merge === ", rows, r);
    }

    int      nDataCols = pDCols->numOfCols;
    int      j = 0, k = 0;
    SCellVal sVal = {0};
    while (j < nDataCols) {
      if (k >= numOfColsIds) break;
      SDataCol *pDataCol = pDCols->cols + j;
      int16_t   colId1 = pDataCol->colId;
      int16_t   colId2 = *(colIds + k);
      if (colId1 < colId2) {
        ++j;
      } else if (colId1 > colId2) {
        ++k;  // colId2 not exists in SDataCols
        printf("NotExists ");
      } else {
        tdGetColDataOfRow(&sVal, pDataCol, r, pDCols->bitmapMode);
        tdSCellValPrint(&sVal, pDataCol->type);
        ++j;
        ++k;
      }
    }
    printf("\n");
  }

  fflush(stdout);
}

// TODO: filter by Multi-Version
int tsdbLoadBlockDataCols(SReadH *pReadh, SBlock *pBlock, SBlockInfo *pBlkInfo, const int16_t *colIds, int numOfColsIds,
                          bool mergeBitmap) {
  ASSERT(pBlock->numOfSubBlocks > 0);
  int8_t update = pReadh->pRepo->pVnode->config.tsdbCfg.update;

  SBlock *iBlock = pBlock;
  if (pBlock->numOfSubBlocks > 1) {
    if (pBlkInfo) {
      iBlock = POINTER_SHIFT(pBlkInfo, pBlock->offset);
    } else {
      iBlock = POINTER_SHIFT(pReadh->pBlkInfo, pBlock->offset);
    }
  }

  if (tsdbLoadBlockDataColsImpl(pReadh, iBlock, pReadh->pDCols[0], colIds, numOfColsIds, TSDB_BITMODE_ONE_BIT) < 0)
    return -1;
#ifdef TD_DEBUG_PRINT_TSDB_LOAD_DCOLS
  printTsdbLoadBlkDataCols(pReadh, pReadh->pDCols[0], iBlock, colIds, numOfColsIds, __func__, __LINE__);
#endif
  for (int i = 1; i < pBlock->numOfSubBlocks; i++) {
    iBlock++;
    if (tsdbLoadBlockDataColsImpl(pReadh, iBlock, pReadh->pDCols[1], colIds, numOfColsIds, TSDB_BITMODE_DEFAULT) < 0)
      return -1;
#ifdef TD_DEBUG_PRINT_TSDB_LOAD_DCOLS
    printTsdbLoadBlkDataCols(pReadh, pReadh->pDCols[1], iBlock, colIds, numOfColsIds, __func__, __LINE__);
#endif
    // TODO: use the real maxVersion to replace the UINT64_MAX to support Multi-Version
    if (tdMergeDataCols(pReadh->pDCols[0], pReadh->pDCols[1], pReadh->pDCols[1]->numOfRows, NULL,
                        TD_SUPPORT_UPDATE(update), TD_VER_MAX) < 0)
      return -1;
#ifdef TD_DEBUG_PRINT_TSDB_LOAD_DCOLS
    printTsdbLoadBlkDataCols(pReadh, pReadh->pDCols[0], NULL, colIds, numOfColsIds, __func__, __LINE__);
#endif
  }
  // if ((pBlock->numOfSubBlocks == 1) && (iBlock->hasDupKey)) { // TODO: use this line
  if (pBlock->numOfSubBlocks == 1) {
    tdResetDataCols(pReadh->pDCols[1]);
    pReadh->pDCols[1]->bitmapMode = pReadh->pDCols[0]->bitmapMode;
    if (tdMergeDataCols(pReadh->pDCols[1], pReadh->pDCols[0], pReadh->pDCols[0]->numOfRows, NULL,
                        TD_SUPPORT_UPDATE(update), TD_VER_MAX) < 0) {
      return -1;
    }
    tsdbSwapDataCols(pReadh->pDCols[0], pReadh->pDCols[1]);
    ASSERT(pReadh->pDCols[0]->bitmapMode != 0);
#ifdef TD_DEBUG_PRINT_TSDB_LOAD_DCOLS
    printTsdbLoadBlkDataCols(pReadh, pReadh->pDCols[0], NULL, colIds, numOfColsIds,
                             " === update filter === ", __LINE__);
#endif
  }

  if (mergeBitmap && !tdDataColsIsBitmapI(pReadh->pDCols[0])) {
    for (int i = 0; i < numOfColsIds; ++i) {
      SDataCol *pDataCol = pReadh->pDCols[0]->cols + i;
      if (pDataCol->len > 0 && pDataCol->bitmap) {
        tdMergeBitmap(pDataCol->pBitmap, pReadh->pDCols[0]->numOfRows, pDataCol->pBitmap);
        tdDataColsSetBitmapI(pReadh->pDCols[0]);
      }
    }
#ifdef TD_DEBUG_PRINT_TSDB_LOAD_DCOLS
    printTsdbLoadBlkDataCols(pReadh, pReadh->pDCols[0], NULL, colIds, numOfColsIds, " === merge bitmap === ", __LINE__);
#endif
  }

  ASSERT(pReadh->pDCols[0]->numOfRows <= pBlock->numOfRows);
  ASSERT(dataColsKeyFirst(pReadh->pDCols[0]) == pBlock->minKey.ts);
  ASSERT(dataColsKeyLast(pReadh->pDCols[0]) == pBlock->maxKey.ts);

  return 0;
}

int tsdbLoadBlockStatis(SReadH *pReadh, SBlock *pBlock) {
  ASSERT(pBlock->numOfSubBlocks <= 1);

  if (!pBlock->aggrStat) {
    tsdbDebug("vgId:%d, no need to load block statis part for uid %" PRIu64 " since not exist", REPO_ID(pReadh->pRepo),
              TSDB_READ_TABLE_UID(pReadh));
    return TSDB_STATIS_NONE;
  }

  SDFile *pDFileAggr = pBlock->last ? TSDB_READ_SMAL_FILE(pReadh) : TSDB_READ_SMAD_FILE(pReadh);

  if (tsdbSeekDFile(pDFileAggr, pBlock->aggrOffset, SEEK_SET) < 0) {
    tsdbError("vgId:%d, failed to load block statis part for uid %" PRIu64 " while seek file %s to offset %" PRIu64
              " since %s",
              TSDB_READ_REPO_ID(pReadh), TSDB_READ_TABLE_UID(pReadh), TSDB_FILE_FULL_NAME(pDFileAggr),
              (uint64_t)pBlock->aggrOffset, tstrerror(terrno));
    return -1;
  }

  size_t sizeAggr = tsdbBlockAggrSize(pBlock->numOfBSma, (uint32_t)pBlock->blkVer);
  if (tsdbMakeRoom((void **)(&(pReadh->pAggrBlkData)), sizeAggr) < 0) return -1;

  int64_t nreadAggr = tsdbReadDFile(pDFileAggr, (void *)(pReadh->pAggrBlkData), sizeAggr);
  if (nreadAggr < 0) {
    tsdbError("vgId:%d, failed to load block statis part for uid %" PRIu64
              " while read file %s since %s, offset:%" PRIu64 " len :%" PRIzu,
              TSDB_READ_REPO_ID(pReadh), TSDB_READ_TABLE_UID(pReadh), TSDB_FILE_FULL_NAME(pDFileAggr),
              tstrerror(terrno), (uint64_t)pBlock->aggrOffset, sizeAggr);
    return -1;
  }

  if (nreadAggr < sizeAggr) {
    terrno = TSDB_CODE_TDB_FILE_CORRUPTED;
    tsdbError("vgId:%d, block statis part for uid %" PRIu64 " in file %s is corrupted, offset:%" PRIu64
              " expected bytes:%" PRIzu " read bytes: %" PRId64,
              TSDB_READ_REPO_ID(pReadh), TSDB_READ_TABLE_UID(pReadh), TSDB_FILE_FULL_NAME(pDFileAggr),
              (uint64_t)pBlock->aggrOffset, sizeAggr, nreadAggr);
    return -1;
  }

  if (!taosCheckChecksumWhole((uint8_t *)(pReadh->pAggrBlkData), (uint32_t)sizeAggr)) {
    terrno = TSDB_CODE_TDB_FILE_CORRUPTED;
    tsdbError("vgId:%d, block statis part for uid %" PRIu64
              "in file %s is corrupted since wrong checksum, offset:%" PRIu64 " len :%" PRIzu,
              TSDB_READ_REPO_ID(pReadh), TSDB_READ_TABLE_UID(pReadh), TSDB_FILE_FULL_NAME(pDFileAggr),
              (uint64_t)pBlock->aggrOffset, sizeAggr);
    return -1;
  }
  return 0;
}

static int tsdbLoadBlockOffset(SReadH *pReadh, SBlock *pBlock) {
  ASSERT(pBlock->numOfSubBlocks <= 1);
  SDFile *pDFile = (pBlock->last) ? TSDB_READ_LAST_FILE(pReadh) : TSDB_READ_DATA_FILE(pReadh);
  if (tsdbSeekDFile(pDFile, pBlock->offset, SEEK_SET) < 0) {
    tsdbError("vgId:%d, failed to load block head part while seek file %s to offset %" PRId64 " since %s",
              TSDB_READ_REPO_ID(pReadh), TSDB_FILE_FULL_NAME(pDFile), (int64_t)pBlock->offset, tstrerror(terrno));
    return -1;
  }

  size_t size = tsdbBlockStatisSize(pBlock->numOfCols, (uint32_t)pBlock->blkVer);
  if (tsdbMakeRoom((void **)(&(pReadh->pBlkData)), size) < 0) return -1;

  int64_t nread = tsdbReadDFile(pDFile, (void *)(pReadh->pBlkData), size);
  if (nread < 0) {
    tsdbError("vgId:%d, failed to load block head part while read file %s since %s, offset:%" PRId64 " len :%" PRIzu,
              TSDB_READ_REPO_ID(pReadh), TSDB_FILE_FULL_NAME(pDFile), tstrerror(terrno), (int64_t)pBlock->offset, size);
    return -1;
  }

  if (nread < size) {
    terrno = TSDB_CODE_TDB_FILE_CORRUPTED;
    tsdbError("vgId:%d, block head part in file %s is corrupted, offset:%" PRId64 " expected bytes:%" PRIzu
              " read bytes: %" PRId64,
              TSDB_READ_REPO_ID(pReadh), TSDB_FILE_FULL_NAME(pDFile), (int64_t)pBlock->offset, size, nread);
    return -1;
  }

  if (!taosCheckChecksumWhole((uint8_t *)(pReadh->pBlkData), (uint32_t)size)) {
    terrno = TSDB_CODE_TDB_FILE_CORRUPTED;
    tsdbError("vgId:%d, block head part in file %s is corrupted since wrong checksum, offset:%" PRId64 " len :%" PRIzu,
              TSDB_READ_REPO_ID(pReadh), TSDB_FILE_FULL_NAME(pDFile), (int64_t)pBlock->offset, size);
    return -1;
  }
  return 0;
}

int tsdbEncodeSBlockIdx(void **buf, SBlockIdx *pIdx) {
  int tlen = 0;

  // tlen += taosEncodeVariantI32(buf, pIdx->tid);
  tlen += taosEncodeVariantU32(buf, pIdx->len);
  tlen += taosEncodeVariantU32(buf, pIdx->offset);
  tlen += taosEncodeFixedU8(buf, pIdx->hasLast);
  tlen += taosEncodeVariantU32(buf, pIdx->numOfBlocks);
  tlen += taosEncodeFixedU64(buf, pIdx->uid);
  tlen += taosEncodeFixedU64(buf, pIdx->maxKey.ts);

  return tlen;
}

void *tsdbDecodeSBlockIdx(void *buf, SBlockIdx *pIdx) {
  uint8_t  hasLast = 0;
  uint32_t numOfBlocks = 0;
  uint64_t value = 0;

  // if ((buf = taosDecodeVariantI32(buf, &(pIdx->tid))) == NULL) return NULL;
  if ((buf = taosDecodeVariantU32(buf, &(pIdx->len))) == NULL) return NULL;
  if ((buf = taosDecodeVariantU32(buf, &(pIdx->offset))) == NULL) return NULL;
  if ((buf = taosDecodeFixedU8(buf, &(hasLast))) == NULL) return NULL;
  pIdx->hasLast = hasLast;
  if ((buf = taosDecodeVariantU32(buf, &(numOfBlocks))) == NULL) return NULL;
  pIdx->numOfBlocks = numOfBlocks;
  if ((buf = taosDecodeFixedU64(buf, &value)) == NULL) return NULL;
  pIdx->uid = (int64_t)value;
  if ((buf = taosDecodeFixedU64(buf, &value)) == NULL) return NULL;
  pIdx->maxKey.ts = (TSKEY)value;

  return buf;
}

void tsdbGetBlockStatis(SReadH *pReadh, SColumnDataAgg *pStatis, int numOfCols, SBlock *pBlock) {
#ifdef TD_REFACTOR_3
  SBlockData *pBlockData = pReadh->pBlkData;

  for (int i = 0, j = 0; i < numOfCols;) {
    if (j >= pBlockData->numOfCols) {
      pStatis[i].numOfNull = -1;
      ++i;
      continue;
    }

    if (pStatis[i].colId == pBlockData->cols[j].colId) {
      pStatis[i].sum = pBlockData->cols[j].sum;
      pStatis[i].max = pBlockData->cols[j].max;
      pStatis[i].min = pBlockData->cols[j].min;
      pStatis[i].maxIndex = pBlockData->cols[j].maxIndex;
      pStatis[i].minIndex = pBlockData->cols[j].minIndex;
      pStatis[i].numOfNull = pBlockData->cols[j].numOfNull;
      ++i;
      ++j;
    } else if (pStatis[i].colId < pBlockData->cols[j].colId) {
      pStatis[i].numOfNull = -1;
      ++i;
    } else {
      ++j;
    }
  }
#else
  if (pBlock->aggrStat) {
    SAggrBlkData *pAggrBlkData = pReadh->pAggrBlkData;

    for (int i = 0, j = 0; i < numOfCols;) {
      if (j >= pBlock->numOfBSma) {
        pStatis[i].numOfNull = -1;
        ++i;
        continue;
      }
      SAggrBlkCol *pAggrBlkCol = ((SAggrBlkCol *)(pAggrBlkData)) + j;
      if (pStatis[i].colId == pAggrBlkCol->colId) {
        pStatis[i].sum = pAggrBlkCol->sum;
        pStatis[i].max = pAggrBlkCol->max;
        pStatis[i].min = pAggrBlkCol->min;
        pStatis[i].maxIndex = pAggrBlkCol->maxIndex;
        pStatis[i].minIndex = pAggrBlkCol->minIndex;
        pStatis[i].numOfNull = pAggrBlkCol->numOfNull;
        ++i;
        ++j;
      } else if (pStatis[i].colId < pAggrBlkCol->colId) {
        pStatis[i].numOfNull = -1;
        ++i;
      } else {
        ++j;
      }
    }
  }

#endif
}

static void tsdbResetReadTable(SReadH *pReadh) {
  tdResetDataCols(pReadh->pDCols[0]);
  tdResetDataCols(pReadh->pDCols[1]);
  pReadh->cidx = 0;
  pReadh->pBlkIdx = NULL;
  pReadh->pTable = NULL;
}

static void tsdbResetReadFile(SReadH *pReadh) {
  tsdbResetReadTable(pReadh);
  taosArrayClear(pReadh->aBlkIdx);
  tsdbCloseDFileSet(TSDB_READ_FSET(pReadh));
}

static int tsdbLoadBlockDataImpl(SReadH *pReadh, SBlock *pBlock, SDataCols *pDataCols, int8_t bitmapMode) {
  ASSERT(pBlock->numOfSubBlocks == 0 || pBlock->numOfSubBlocks == 1);

  SDFile *pDFile = (pBlock->last) ? TSDB_READ_LAST_FILE(pReadh) : TSDB_READ_DATA_FILE(pReadh);

  tdResetDataCols(pDataCols);

  pDataCols->bitmapMode = bitmapMode;

  if (tsdbMakeRoom((void **)(&TSDB_READ_BUF(pReadh)), pBlock->len) < 0) return -1;

  SBlockData *pBlockData = (SBlockData *)TSDB_READ_BUF(pReadh);

  if (tsdbSeekDFile(pDFile, pBlock->offset, SEEK_SET) < 0) {
    tsdbError("vgId:%d, failed to load block data part while seek file %s to offset %" PRId64 " since %s",
              TSDB_READ_REPO_ID(pReadh), TSDB_FILE_FULL_NAME(pDFile), (int64_t)pBlock->offset, tstrerror(terrno));
    return -1;
  }

  int64_t nread = tsdbReadDFile(pDFile, TSDB_READ_BUF(pReadh), pBlock->len);
  if (nread < 0) {
    tsdbError("vgId:%d, failed to load block data part while read file %s since %s, offset:%" PRId64 " len :%d",
              TSDB_READ_REPO_ID(pReadh), TSDB_FILE_FULL_NAME(pDFile), tstrerror(terrno), (int64_t)pBlock->offset,
              pBlock->len);
    return -1;
  }

  if (nread < pBlock->len) {
    terrno = TSDB_CODE_TDB_FILE_CORRUPTED;
    tsdbError("vgId:%d, block data part in file %s is corrupted, offset:%" PRId64
              " expected bytes:%d read bytes: %" PRId64,
              TSDB_READ_REPO_ID(pReadh), TSDB_FILE_FULL_NAME(pDFile), (int64_t)pBlock->offset, pBlock->len, nread);
    return -1;
  }

  int32_t tsize = (int32_t)tsdbBlockStatisSize(pBlock->numOfCols, (uint32_t)pBlock->blkVer);
  if (!taosCheckChecksumWhole((uint8_t *)TSDB_READ_BUF(pReadh), tsize)) {
    terrno = TSDB_CODE_TDB_FILE_CORRUPTED;
    tsdbError("vgId:%d, block head part in file %s is corrupted since wrong checksum, offset:%" PRId64 " len :%d",
              TSDB_READ_REPO_ID(pReadh), TSDB_FILE_FULL_NAME(pDFile), (int64_t)pBlock->offset, tsize);
    return -1;
  }

  ASSERT(tsize < pBlock->len);
  ASSERT(pBlockData->numOfCols == pBlock->numOfCols);

  pDataCols->numOfRows = pBlock->numOfRows;

  // Recover the data
  int        ccol = 0;  // loop iter for SBlockCol object
  int        dcol = 0;  // loop iter for SDataCols object
  int        nBitmaps = (int)TD_BITMAP_BYTES(pBlock->numOfRows);
  SBlockCol *pBlockCol = NULL;
  while (dcol < pDataCols->numOfCols) {
    SDataCol *pDataCol = &(pDataCols->cols[dcol]);
    if (dcol != 0 && ccol >= pBlockData->numOfCols) {
      // Set current column as NULL and forward
      dataColReset(pDataCol);
      ++dcol;
      continue;
    }

    int16_t  tcolId = PRIMARYKEY_TIMESTAMP_COL_ID;
    uint32_t toffset = TSDB_KEY_COL_OFFSET;
    int32_t  tlen = pBlock->keyLen;

    if (dcol != 0) {
      pBlockCol = &(pBlockData->cols[ccol]);
      tcolId = pBlockCol->colId;
      toffset = pBlockCol->offset;
      tlen = pBlockCol->len;
      pDataCol->bitmap = pBlockCol->blen > 0 ? 1 : 0;
    } else {
      ASSERT(pDataCol->colId == tcolId);
      TD_SET_COL_ROWS_NORM(pDataCol);
    }

    // int32_t tBitmaps = 0;
    int32_t tLenBitmap = 0;
    if ((dcol != 0) && (pBlockCol->blen > 0)) {
      tLenBitmap = nBitmaps;
    }

    if (tcolId == pDataCol->colId) {
      if (pBlock->algorithm == TWO_STAGE_COMP) {
        int zsize = pDataCol->bytes * pBlock->numOfRows + tLenBitmap + 2 * COMP_OVERFLOW_BYTES;
        if (tsdbMakeRoom((void **)(&TSDB_READ_COMP_BUF(pReadh)), zsize) < 0) return -1;
      }

      if (tsdbCheckAndDecodeColumnData(pDataCol, POINTER_SHIFT(pBlockData, tsize + toffset), tlen,
                                       pBlockCol ? pBlockCol->blen : 0, pBlock->algorithm, pBlock->numOfRows,
                                       tLenBitmap, pDataCols->maxPoints, TSDB_READ_COMP_BUF(pReadh),
                                       (int)taosTSizeof(TSDB_READ_COMP_BUF(pReadh))) < 0) {
        tsdbError("vgId:%d, file %s is broken at column %d block offset %" PRId64 " column offset %u",
                  TSDB_READ_REPO_ID(pReadh), TSDB_FILE_FULL_NAME(pDFile), tcolId, (int64_t)pBlock->offset, toffset);
        return -1;
      }

      if (dcol != 0) {
        ++ccol;
      }
      ++dcol;
    } else if (tcolId < pDataCol->colId) {
      ++ccol;
    } else {
      // Set current column as NULL and forward
      dataColReset(pDataCol);
      ++dcol;
    }
  }

  return 0;
}

static int tsdbCheckAndDecodeColumnData(SDataCol *pDataCol, void *content, int32_t len, int32_t bitmapLen, int8_t comp,
                                        int numOfRows, int numOfBitmaps, int maxPoints, char *buffer, int bufferSize) {
  if (!taosCheckChecksumWhole((uint8_t *)content, len)) {
    terrno = TSDB_CODE_TDB_FILE_CORRUPTED;
    return -1;
  }

  tdAllocMemForCol(pDataCol, maxPoints);

  // Decode the data
  if (comp) {
    // Need to decompress
    int tlen =
        (*(tDataTypes[pDataCol->type].decompFunc))(content, len - bitmapLen - sizeof(TSCKSUM), numOfRows,
                                                   pDataCol->pData, pDataCol->spaceSize, comp, buffer, bufferSize);
    if (tlen <= 0) {
      tsdbError(
          "Failed to decompress column data, file corrupted, len:%d comp:%d numOfRows:%d maxPoints:%d bufferSize:%d",
          (int32_t)(len - bitmapLen - sizeof(TSCKSUM)), comp, numOfRows, maxPoints, bufferSize);
      terrno = TSDB_CODE_TDB_FILE_CORRUPTED;
      return -1;
    }
    pDataCol->len = tlen;

    if (numOfBitmaps > 0) {
      tlen = tsDecompressTinyint(POINTER_SHIFT(content, len - bitmapLen - sizeof(TSCKSUM)), bitmapLen, numOfBitmaps,
                                 pDataCol->pBitmap, pDataCol->spaceSize, comp, buffer, bufferSize);
      if (tlen <= 0) {
        tsdbError(
            "Failed to decompress column bitmap, file corrupted, len:%d comp:%d numOfRows:%d maxPoints:%d "
            "bufferSize:%d",
            bitmapLen, comp, numOfBitmaps, maxPoints, bufferSize);
        terrno = TSDB_CODE_TDB_FILE_CORRUPTED;
        return -1;
      }
      // pDataCol->blen = tlen;
    }
  } else {
    // No need to decompress, just memcpy it
    pDataCol->len = len - bitmapLen - sizeof(TSCKSUM);
    memcpy(pDataCol->pData, content, pDataCol->len);
    if (numOfBitmaps > 0) {
      // pDataCol->blen = bitmapLen;
      memcpy(pDataCol->pBitmap, POINTER_SHIFT(content, len - bitmapLen - sizeof(TSCKSUM)), bitmapLen);
    }
  }

#if 0
  if (lenOfBitmaps > 0) {
    pDataCol->len -= lenOfBitmaps;

    void *pSrcBitmap = NULL;
    if (IS_VAR_DATA_TYPE(pDataCol->type)) {
      pSrcBitmap = dataColSetOffset(pDataCol, numOfRows);
    } else {
      pSrcBitmap = POINTER_SHIFT(pDataCol->pData, numOfRows * TYPE_BYTES[pDataCol->type]);
    }
    void *pDestBitmap = POINTER_SHIFT(pDataCol->pData, pDataCol->bytes * maxPoints);
    // restore the bitmap parts
    memcpy(pDestBitmap, pSrcBitmap, lenOfBitmaps);
  } else if (IS_VAR_DATA_TYPE(pDataCol->type)) {
    dataColSetOffset(pDataCol, numOfRows);
  }
#endif
  if (IS_VAR_DATA_TYPE(pDataCol->type)) {
    dataColSetOffset(pDataCol, numOfRows);
  }
  return 0;
}

static int tsdbLoadBlockDataColsImpl(SReadH *pReadh, SBlock *pBlock, SDataCols *pDataCols, const int16_t *colIds,
                                     int numOfColIds, int8_t bitmapMode) {
  ASSERT(pBlock->numOfSubBlocks == 0 || pBlock->numOfSubBlocks == 1);
  ASSERT(colIds[0] == PRIMARYKEY_TIMESTAMP_COL_ID);

  SDFile   *pDFile = (pBlock->last) ? TSDB_READ_LAST_FILE(pReadh) : TSDB_READ_DATA_FILE(pReadh);
  SBlockCol blockCol = {0};

  tdResetDataCols(pDataCols);

  pDataCols->bitmapMode = bitmapMode;

  // If only load timestamp column, no need to load SBlockData part
  if (numOfColIds > 1 && tsdbLoadBlockOffset(pReadh, pBlock) < 0) return -1;

  pDataCols->numOfRows = pBlock->numOfRows;

  int dcol = 0;
  int ccol = 0;
  for (int i = 0; i < numOfColIds; i++) {
    int16_t    colId = colIds[i];
    SDataCol  *pDataCol = NULL;
    SBlockCol *pBlockCol = NULL;

    while (true) {
      if (dcol >= pDataCols->numOfCols) {
        pDataCol = NULL;
        break;
      }
      pDataCol = &pDataCols->cols[dcol];
      if (pDataCol->colId > colId) {
        pDataCol = NULL;
        break;
      } else {
        dcol++;
        if (pDataCol->colId == colId) break;
      }
    }

    if (pDataCol == NULL) continue;
    ASSERT(pDataCol->colId == colId);

    if (colId == PRIMARYKEY_TIMESTAMP_COL_ID) {  // load the key row
      blockCol.colId = colId;
      blockCol.blen = 0;  // default is NORM for the primary key column
      blockCol.len = pBlock->keyLen;
      blockCol.type = pDataCol->type;
      blockCol.offset = TSDB_KEY_COL_OFFSET;
      pBlockCol = &blockCol;
    } else {  // load non-key rows
      while (true) {
        if (ccol >= pBlock->numOfCols) {
          pBlockCol = NULL;
          break;
        }

        pBlockCol = &(pReadh->pBlkData->cols[ccol]);
        if (pBlockCol->colId > colId) {
          pBlockCol = NULL;
          break;
        } else {
          ccol++;
          if (pBlockCol->colId == colId) break;
        }
      }

      if (pBlockCol == NULL) {
        dataColReset(pDataCol);
        continue;
      }

      ASSERT(pBlockCol->colId == pDataCol->colId);
    }
    // set the bitmap
    pDataCol->bitmap = pBlockCol->blen > 0 ? 1 : 0;

    if (tsdbLoadColData(pReadh, pDFile, pBlock, pBlockCol, pDataCol) < 0) return -1;
  }

  return 0;
}

static int tsdbLoadColData(SReadH *pReadh, SDFile *pDFile, SBlock *pBlock, SBlockCol *pBlockCol, SDataCol *pDataCol) {
  ASSERT(pDataCol->colId == pBlockCol->colId);

  STsdb    *pRepo = TSDB_READ_REPO(pReadh);
  STsdbCfg *pCfg = REPO_CFG(pRepo);

  int nBitmaps = (int)TD_BITMAP_BYTES(pBlock->numOfRows);
  // int32_t tBitmaps = 0;
  int32_t tLenBitmap = 0;

  if (pBlockCol->blen) {
    tLenBitmap = nBitmaps;
  }

  int tsize = pDataCol->bytes * pBlock->numOfRows + tLenBitmap + 2 * COMP_OVERFLOW_BYTES;

  if (tsdbMakeRoom((void **)(&TSDB_READ_BUF(pReadh)), pBlockCol->len) < 0) return -1;
  if (tsdbMakeRoom((void **)(&TSDB_READ_COMP_BUF(pReadh)), tsize) < 0) return -1;

  int64_t offset =
      pBlock->offset + tsdbBlockStatisSize(pBlock->numOfCols, (uint32_t)pBlock->blkVer) + pBlockCol->offset;
  if (tsdbSeekDFile(pDFile, offset, SEEK_SET) < 0) {
    tsdbError("vgId:%d, failed to load block column data while seek file %s to offset %" PRId64 " since %s",
              TSDB_READ_REPO_ID(pReadh), TSDB_FILE_FULL_NAME(pDFile), offset, tstrerror(terrno));
    return -1;
  }

  int64_t nread = tsdbReadDFile(pDFile, TSDB_READ_BUF(pReadh), pBlockCol->len);
  if (nread < 0) {
    tsdbError("vgId:%d, failed to load block column data while read file %s since %s, offset:%" PRId64 " len :%d",
              TSDB_READ_REPO_ID(pReadh), TSDB_FILE_FULL_NAME(pDFile), tstrerror(terrno), offset, pBlockCol->len);
    return -1;
  }

  if (nread < pBlockCol->len) {
    terrno = TSDB_CODE_TDB_FILE_CORRUPTED;
    tsdbError("vgId:%d, block column data in file %s is corrupted, offset:%" PRId64 " expected bytes:%d" PRIzu
              " read bytes: %" PRId64,
              TSDB_READ_REPO_ID(pReadh), TSDB_FILE_FULL_NAME(pDFile), offset, pBlockCol->len, nread);
    return -1;
  }

  if (tsdbCheckAndDecodeColumnData(pDataCol, pReadh->pBuf, pBlockCol->len, pBlockCol->blen, pBlock->algorithm,
                                   pBlock->numOfRows, tLenBitmap, pCfg->maxRows, pReadh->pCBuf,
                                   (int32_t)taosTSizeof(pReadh->pCBuf)) < 0) {
    tsdbError("vgId:%d, file %s is broken at column %d offset %" PRId64, REPO_ID(pRepo), TSDB_FILE_FULL_NAME(pDFile),
              pBlockCol->colId, offset);
    return -1;
  }

  return 0;
}