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Comment:When computing the amount of scratch memory needed during a rebalance operation, assume the worst case for the number of cells per page, rather than relying on the BtPage.nCell value, which might be incorrect for a corrupt database.
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SHA3-256: a420ebd08f5a96b9e61a37cb42e1b3f346c23505630d9c33fe30ce7882959b36
User & Date: drh 2019-03-19 15:36:46.725
Context
2019-03-19
20:13
Fix a compiler warning in FTS5. (check-in: d5acf3af65 user: drh tags: trunk)
15:36
When computing the amount of scratch memory needed during a rebalance operation, assume the worst case for the number of cells per page, rather than relying on the BtPage.nCell value, which might be incorrect for a corrupt database. (check-in: a420ebd08f user: drh tags: trunk)
11:35
Tweak the tool/cg_anno.tcl script so that it can run on systems without /usr/bin/tclsh. (check-in: a026189aa4 user: dan tags: trunk)
Changes
Unified Diff Ignore Whitespace Patch
Changes to src/btree.c.
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    if( apOld[i]->nFree<0 ){
      rc = btreeComputeFreeSpace(apOld[i]);
      if( rc ){
        memset(apOld, 0, (i)*sizeof(MemPage*));
        goto balance_cleanup;
      }
    }
    nMaxCells += 1+apOld[i]->nCell+apOld[i]->nOverflow;
    if( (i--)==0 ) break;

    if( pParent->nOverflow && i+nxDiv==pParent->aiOvfl[0] ){
      apDiv[i] = pParent->apOvfl[0];
      pgno = get4byte(apDiv[i]);
      szNew[i] = pParent->xCellSize(pParent, apDiv[i]);
      pParent->nOverflow = 0;








<








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    if( apOld[i]->nFree<0 ){
      rc = btreeComputeFreeSpace(apOld[i]);
      if( rc ){
        memset(apOld, 0, (i)*sizeof(MemPage*));
        goto balance_cleanup;
      }
    }

    if( (i--)==0 ) break;

    if( pParent->nOverflow && i+nxDiv==pParent->aiOvfl[0] ){
      apDiv[i] = pParent->apOvfl[0];
      pgno = get4byte(apDiv[i]);
      szNew[i] = pParent->xCellSize(pParent, apDiv[i]);
      pParent->nOverflow = 0;
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      }
      dropCell(pParent, i+nxDiv-pParent->nOverflow, szNew[i], &rc);
    }
  }

  /* Make nMaxCells a multiple of 4 in order to preserve 8-byte
  ** alignment */

  nMaxCells = (nMaxCells + 3)&~3;

  /*
  ** Allocate space for memory structures
  */
  szScratch =
       nMaxCells*sizeof(u8*)                       /* b.apCell */
     + nMaxCells*sizeof(u16)                       /* b.szCell */
     + pBt->pageSize;                              /* aSpace1 */

  assert( szScratch<=6*(int)pBt->pageSize );
  b.apCell = sqlite3StackAllocRaw(0, szScratch );
  if( b.apCell==0 ){
    rc = SQLITE_NOMEM_BKPT;
    goto balance_cleanup;
  }
  b.szCell = (u16*)&b.apCell[nMaxCells];
  aSpace1 = (u8*)&b.szCell[nMaxCells];








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      }
      dropCell(pParent, i+nxDiv-pParent->nOverflow, szNew[i], &rc);
    }
  }

  /* Make nMaxCells a multiple of 4 in order to preserve 8-byte
  ** alignment */
  nMaxCells = nOld*(MX_CELL(pBt) + ArraySize(pParent->apOvfl));
  nMaxCells = (nMaxCells + 3)&~3;

  /*
  ** Allocate space for memory structures
  */
  szScratch =
       nMaxCells*sizeof(u8*)                       /* b.apCell */
     + nMaxCells*sizeof(u16)                       /* b.szCell */
     + pBt->pageSize;                              /* aSpace1 */

  assert( szScratch<=7*(int)pBt->pageSize );
  b.apCell = sqlite3StackAllocRaw(0, szScratch );
  if( b.apCell==0 ){
    rc = SQLITE_NOMEM_BKPT;
    goto balance_cleanup;
  }
  b.szCell = (u16*)&b.apCell[nMaxCells];
  aSpace1 = (u8*)&b.szCell[nMaxCells];
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