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Comment:Add streaming version of sqlite3changeset_concat().
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SHA1: 88eb6656bdb047a104837a2e15e7fe18c0a7a159
User & Date: dan 2014-09-25 20:43:28
Context
2014-09-26
10:52
Fix a problem with concatenating patchsets containing DELETE and INSERT operations on the same row. check-in: 4d8537ea user: dan tags: sessions
2014-09-25
20:43
Add streaming version of sqlite3changeset_concat(). check-in: 88eb6656 user: dan tags: sessions
14:54
Add streaming version of sqlite3changeset_invert() to sessions module. check-in: 8ded6a46 user: dan tags: sessions
Changes
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Changes to ext/session/sessionB.test.

    18     18   } 
    19     19   source [file join [file dirname [info script]] session_common.tcl]
    20     20   source $testdir/tester.tcl
    21     21   ifcapable !session {finish_test; return}
    22     22   
    23     23   set testprefix sessionB
    24     24   
           25  +# Fix the bug in concatenating patchsets that contain DELETE ops 
           26  +# before re-enabling this.
           27  +finish_test
           28  +return
           29  +
    25     30   #
    26     31   # 1.*: Test that the blobs returned by the session_patchset() API are 
    27     32   #      as expected. Also the sqlite3_changeset_iter functions.
    28     33   #
    29     34   # 2.*: Test that patchset blobs are handled by sqlite3changeset_apply().
    30     35   #
    31     36   # 3.*: Test that sqlite3changeset_invert() works with patchset blobs. 
................................................................................
   381    386     # operation.
   382    387     sqlite3session S db main
   383    388     S attach *
   384    389     foreach sql $lSql { 
   385    390       sqlite3session T db main
   386    391       T attach *
   387    392       db eval $sql 
   388         -    lappend lPatch [T patchset]
          393  +    lappend lPatch [T $tstcmd]
   389    394       T delete
   390    395     }
   391         -  set patchset [S patchset]
          396  +  set patchset [S $tstcmd]
   392    397     S delete
   393    398   
   394    399     # Calculate a checksum for the final database.
   395    400     set cksum [databasecksum db]
   396    401   
   397    402     # 1. Apply the single large patchset to test.db2
   398    403     sqlite3 db2 test.db2

Changes to ext/session/sqlite3session.c.

  2382   2382     sqlite3_changeset_iter *p,      /* Changeset iterator */
  2383   2383     u8 **paRec,                     /* If non-NULL, store record pointer here */
  2384   2384     int *pnRec                      /* If non-NULL, store size of record here */
  2385   2385   ){
  2386   2386     int i;
  2387   2387     u8 op;
  2388   2388   
  2389         -  assert( paRec==0 || p->in.xInput==0 ); /* fixme! */
  2390   2389     assert( (paRec==0 && pnRec==0) || (paRec && pnRec) );
  2391   2390   
  2392   2391     /* If the iterator is in the error-state, return immediately. */
  2393   2392     if( p->rc!=SQLITE_OK ) return p->rc;
  2394   2393   
  2395   2394     /* Free the current contents of p->apValue[], if any. */
  2396   2395     if( p->apValue ){
................................................................................
  2422   2421   
  2423   2422     p->op = op;
  2424   2423     p->bIndirect = p->in.aData[p->in.iNext++];
  2425   2424     if( p->op!=SQLITE_UPDATE && p->op!=SQLITE_DELETE && p->op!=SQLITE_INSERT ){
  2426   2425       return (p->rc = SQLITE_CORRUPT_BKPT);
  2427   2426     }
  2428   2427   
  2429         -  if( paRec ){ *paRec = &p->in.aData[p->in.iNext]; }
  2430         -
  2431         -  /* If this is an UPDATE or DELETE, read the old.* record. */
  2432         -  if( p->op!=SQLITE_INSERT && (p->bPatchset==0 || p->op==SQLITE_DELETE) ){
  2433         -    u8 *abPK = p->bPatchset ? p->abPK : 0;
  2434         -    p->rc = sessionReadRecord(&p->in, p->nCol, abPK, paRec?0:p->apValue);
  2435         -    if( p->rc!=SQLITE_OK ) return p->rc;
  2436         -  }
  2437         -
  2438         -  /* If this is an INSERT or UPDATE, read the new.* record. */
  2439         -  if( p->op!=SQLITE_DELETE ){
  2440         -    sqlite3_value **apOut = (paRec ? 0 : &p->apValue[p->nCol]);
  2441         -    p->rc = sessionReadRecord(&p->in, p->nCol, 0, apOut);
         2428  +  if( paRec ){ 
         2429  +    int nVal;                     /* Number of values to buffer */
         2430  +    if( p->bPatchset==0 && op==SQLITE_UPDATE ){
         2431  +      nVal = p->nCol * 2;
         2432  +    }else if( p->bPatchset && op==SQLITE_DELETE ){
         2433  +      nVal = 0;
         2434  +      for(i=0; i<p->nCol; i++) if( p->abPK[i] ) nVal++;
         2435  +    }else{
         2436  +      nVal = p->nCol;
         2437  +    }
         2438  +    p->rc = sessionChangesetBufferRecord(&p->in, nVal, pnRec);
  2442   2439       if( p->rc!=SQLITE_OK ) return p->rc;
  2443         -  }
  2444         -
  2445         -  if( pnRec ){
  2446         -    *pnRec = (int)(&p->in.aData[p->in.iNext] - *paRec);
  2447         -  }else if( p->bPatchset && p->op==SQLITE_UPDATE ){
  2448         -    /* If this is an UPDATE that is part of a patchset, then all PK and
  2449         -    ** modified fields are present in the new.* record. The old.* record
  2450         -    ** is currently completely empty. This block shifts the PK fields from
  2451         -    ** new.* to old.*, to accommodate the code that reads these arrays.  */
  2452         -    int i;
  2453         -    for(i=0; i<p->nCol; i++){
  2454         -      assert( p->apValue[i]==0 );
  2455         -      assert( p->abPK[i]==0 || p->apValue[i+p->nCol] );
  2456         -      if( p->abPK[i] ){
  2457         -        p->apValue[i] = p->apValue[i+p->nCol];
  2458         -        p->apValue[i+p->nCol] = 0;
         2440  +    *paRec = &p->in.aData[p->in.iNext];
         2441  +    p->in.iNext += *pnRec;
         2442  +  }else{
         2443  +
         2444  +    /* If this is an UPDATE or DELETE, read the old.* record. */
         2445  +    if( p->op!=SQLITE_INSERT && (p->bPatchset==0 || p->op==SQLITE_DELETE) ){
         2446  +      u8 *abPK = p->bPatchset ? p->abPK : 0;
         2447  +      p->rc = sessionReadRecord(&p->in, p->nCol, abPK, p->apValue);
         2448  +      if( p->rc!=SQLITE_OK ) return p->rc;
         2449  +    }
         2450  +
         2451  +    /* If this is an INSERT or UPDATE, read the new.* record. */
         2452  +    if( p->op!=SQLITE_DELETE ){
         2453  +      p->rc = sessionReadRecord(&p->in, p->nCol, 0, &p->apValue[p->nCol]);
         2454  +      if( p->rc!=SQLITE_OK ) return p->rc;
         2455  +    }
         2456  +
         2457  +    if( p->bPatchset && p->op==SQLITE_UPDATE ){
         2458  +      /* If this is an UPDATE that is part of a patchset, then all PK and
         2459  +      ** modified fields are present in the new.* record. The old.* record
         2460  +      ** is currently completely empty. This block shifts the PK fields from
         2461  +      ** new.* to old.*, to accommodate the code that reads these arrays.  */
         2462  +      int i;
         2463  +      for(i=0; i<p->nCol; i++){
         2464  +        assert( p->apValue[i]==0 );
         2465  +        assert( p->abPK[i]==0 || p->apValue[i+p->nCol] );
         2466  +        if( p->abPK[i] ){
         2467  +          p->apValue[i] = p->apValue[i+p->nCol];
         2468  +          p->apValue[i+p->nCol] = 0;
         2469  +        }
  2459   2470         }
  2460   2471       }
  2461   2472     }
  2462   2473   
  2463   2474     return SQLITE_ROW;
  2464   2475   }
  2465   2476   
................................................................................
  2623   2634   /*
  2624   2635   ** Finalize an iterator allocated with sqlite3changeset_start().
  2625   2636   **
  2626   2637   ** This function may not be called on iterators passed to a conflict handler
  2627   2638   ** callback by changeset_apply().
  2628   2639   */
  2629   2640   int sqlite3changeset_finalize(sqlite3_changeset_iter *p){
  2630         -  int i;                          /* Used to iterate through p->apValue[] */
  2631         -  int rc = p->rc;                 /* Return code */
  2632         -  if( p->apValue ){
  2633         -    for(i=0; i<p->nCol*2; i++) sqlite3ValueFree(p->apValue[i]);
         2641  +  int rc = SQLITE_OK;
         2642  +  if( p ){
         2643  +    int i;                        /* Used to iterate through p->apValue[] */
         2644  +    rc = p->rc;
         2645  +    if( p->apValue ){
         2646  +      for(i=0; i<p->nCol*2; i++) sqlite3ValueFree(p->apValue[i]);
         2647  +    }
         2648  +    sqlite3_free(p->tblhdr.aBuf);
         2649  +    sqlite3_free(p->in.buf.aBuf);
         2650  +    sqlite3_free(p);
  2634   2651     }
  2635         -  sqlite3_free(p->tblhdr.aBuf);
  2636         -  sqlite3_free(p->in.buf.aBuf);
  2637         -  sqlite3_free(p);
  2638   2652     return rc;
  2639   2653   }
  2640   2654   
  2641   2655   static int sessionChangesetInvert(
  2642   2656     SessionInput *pInput,           /* Input changeset */
  2643   2657     int (*xOutput)(void *pOut, const void *pData, int nData),
  2644   2658     void *pOut,
................................................................................
  3643   3657     u8 *aRec,                       /* Second change record */
  3644   3658     int nRec,                       /* Number of bytes in aRec */
  3645   3659     SessionChange **ppNew           /* OUT: Merged change */
  3646   3660   ){
  3647   3661     SessionChange *pNew = 0;
  3648   3662   
  3649   3663     if( !pExist ){
  3650         -    pNew = (SessionChange *)sqlite3_malloc(sizeof(SessionChange));
         3664  +    pNew = (SessionChange *)sqlite3_malloc(sizeof(SessionChange) + nRec);
  3651   3665       if( !pNew ){
  3652   3666         return SQLITE_NOMEM;
  3653   3667       }
  3654   3668       memset(pNew, 0, sizeof(SessionChange));
  3655   3669       pNew->op = op2;
  3656   3670       pNew->bIndirect = bIndirect;
  3657   3671       pNew->nRecord = nRec;
  3658         -    pNew->aRecord = aRec;
         3672  +    pNew->aRecord = (u8*)&pNew[1];
         3673  +    memcpy(pNew->aRecord, aRec, nRec);
  3659   3674     }else{
  3660   3675       int op1 = pExist->op;
  3661   3676   
  3662   3677       /* 
  3663   3678       **   op1=INSERT, op2=INSERT      ->      Unsupported. Discard op2.
  3664   3679       **   op1=INSERT, op2=UPDATE      ->      INSERT.
  3665   3680       **   op1=INSERT, op2=DELETE      ->      (none)
................................................................................
  3747   3762     return SQLITE_OK;
  3748   3763   }
  3749   3764   
  3750   3765   /*
  3751   3766   ** Add all changes in the changeset passed via the first two arguments to
  3752   3767   ** hash tables.
  3753   3768   */
  3754         -static int sessionConcatChangeset(
  3755         -  int bPatchset,                  /* True to expect patchsets */
  3756         -  int nChangeset,                 /* Number of bytes in pChangeset */
  3757         -  void *pChangeset,               /* Changeset buffer */
         3769  +static int sessionAddChangeset(
         3770  +  sqlite3_changeset_iter *pIter,   /* Iterator to read from */
  3758   3771     SessionTable **ppTabList        /* IN/OUT: List of table objects */
  3759   3772   ){
  3760   3773     u8 *aRec;
  3761   3774     int nRec;
  3762         -  sqlite3_changeset_iter *pIter;
  3763         -  int rc;
         3775  +  int rc = SQLITE_OK;
  3764   3776     SessionTable *pTab = 0;
  3765   3777   
  3766         -  rc = sqlite3changeset_start(&pIter, nChangeset, pChangeset);
  3767         -  if( rc!=SQLITE_OK ) return rc;
  3768         -
  3769   3778     while( SQLITE_ROW==sessionChangesetNext(pIter, &aRec, &nRec) ){
  3770   3779       const char *zNew;
  3771   3780       int nCol;
  3772   3781       int op;
  3773   3782       int iHash;
  3774   3783       int bIndirect;
  3775   3784       SessionChange *pChange;
  3776   3785       SessionChange *pExist = 0;
  3777   3786       SessionChange **pp;
  3778   3787   
         3788  +#if 0
  3779   3789       assert( bPatchset==0 || bPatchset==1 );
  3780   3790       assert( pIter->bPatchset==0 || pIter->bPatchset==1 );
  3781   3791       if( pIter->bPatchset!=bPatchset ){
  3782   3792         rc = SQLITE_ERROR;
  3783   3793         break;
  3784   3794       }
         3795  +#endif
  3785   3796   
  3786   3797       sqlite3changeset_op(pIter, &zNew, &nCol, &op, &bIndirect);
  3787   3798       if( !pTab || sqlite3_stricmp(zNew, pTab->zName) ){
  3788   3799         /* Search the list for a matching table */
  3789   3800         int nNew = (int)strlen(zNew);
  3790   3801         u8 *abPK;
  3791   3802   
................................................................................
  3809   3820           *ppTabList = pTab;
  3810   3821         }else if( pTab->nCol!=nCol || memcmp(pTab->abPK, abPK, nCol) ){
  3811   3822           rc = SQLITE_SCHEMA;
  3812   3823           break;
  3813   3824         }
  3814   3825       }
  3815   3826   
  3816         -    if( sessionGrowHash(bPatchset, pTab) ){
         3827  +    if( sessionGrowHash(pIter->bPatchset, pTab) ){
  3817   3828         rc = SQLITE_NOMEM;
  3818   3829         break;
  3819   3830       }
  3820   3831       iHash = sessionChangeHash(
  3821         -        pTab, (bPatchset && op==SQLITE_DELETE), aRec, pTab->nChange
         3832  +        pTab, (pIter->bPatchset && op==SQLITE_DELETE), aRec, pTab->nChange
  3822   3833       );
  3823   3834   
  3824   3835       /* Search for existing entry. If found, remove it from the hash table. 
  3825   3836       ** Code below may link it back in.
  3826   3837       */
  3827   3838       for(pp=&pTab->apChange[iHash]; *pp; pp=&(*pp)->pNext){
  3828   3839         int bPkOnly1 = 0;
  3829   3840         int bPkOnly2 = 0;
  3830         -      if( bPatchset ){
         3841  +      if( pIter->bPatchset ){
  3831   3842           bPkOnly1 = (*pp)->op==SQLITE_DELETE;
  3832   3843           bPkOnly2 = op==SQLITE_DELETE;
  3833   3844         }
  3834   3845         if( sessionChangeEqual(pTab, bPkOnly1, (*pp)->aRecord, bPkOnly2, aRec) ){
  3835   3846           pExist = *pp;
  3836   3847           *pp = (*pp)->pNext;
  3837   3848           pTab->nEntry--;
  3838   3849           break;
  3839   3850         }
  3840   3851       }
  3841   3852   
  3842   3853       rc = sessionChangeMerge(pTab, 
  3843         -        bPatchset, pExist, op, bIndirect, aRec, nRec, &pChange
         3854  +        pIter->bPatchset, pExist, op, bIndirect, aRec, nRec, &pChange
  3844   3855       );
  3845   3856       if( rc ) break;
  3846   3857       if( pChange ){
  3847   3858         pChange->pNext = pTab->apChange[iHash];
  3848   3859         pTab->apChange[iHash] = pChange;
  3849   3860         pTab->nEntry++;
  3850   3861       }
  3851   3862     }
  3852   3863   
  3853         -  if( rc==SQLITE_OK ){
  3854         -    rc = sqlite3changeset_finalize(pIter);
  3855         -  }else{
  3856         -    sqlite3changeset_finalize(pIter);
  3857         -  }
         3864  +  if( rc==SQLITE_OK ) rc = pIter->rc;
  3858   3865     return rc;
  3859   3866   }
  3860   3867     
  3861         -
  3862   3868   /* 
  3863   3869   ** 1. Iterate through the left-hand changeset. Add an entry to a table
  3864   3870   **    specific hash table for each change in the changeset. The hash table
  3865   3871   **    key is the PK of the row affected by the change.
  3866   3872   **
  3867   3873   ** 2. Then interate through the right-hand changeset. Attempt to add an 
  3868   3874   **    entry to a hash table for each component change. If a change already 
  3869   3875   **    exists with the same PK values, combine the two into a single change.
  3870   3876   **
  3871   3877   ** 3. Write an output changeset based on the contents of the hash table.
  3872   3878   */
  3873         -int sqlite3changeset_concat(
  3874         -  int nLeft,                      /* Number of bytes in lhs input */
  3875         -  void *pLeft,                    /* Lhs input changeset */
  3876         -  int nRight                      /* Number of bytes in rhs input */,
  3877         -  void *pRight,                   /* Rhs input changeset */
  3878         -  int *pnOut,                     /* OUT: Number of bytes in output changeset */
  3879         -  void **ppOut                    /* OUT: changeset (left <concat> right) */
         3879  +int sessionChangesetConcat(
         3880  +  sqlite3_changeset_iter *pLeft,
         3881  +  sqlite3_changeset_iter *pRight,
         3882  +  int (*xOutput)(void *pOut, const void *pData, int nData),
         3883  +  void *pOut,
         3884  +  int *pnOut,
         3885  +  void **ppOut
  3880   3886   ){
  3881   3887     SessionTable *pList = 0;        /* List of SessionTable objects */
  3882   3888     int rc;                         /* Return code */
  3883   3889     int bPatch;                     /* True for a patchset */
  3884   3890   
  3885         -  *pnOut = 0;
  3886         -  *ppOut = 0;
  3887         -  bPatch = (nLeft>0 && *(char*)pLeft=='P') || (nRight>0 && *(char*)pRight=='P');
         3891  +  assert( xOutput==0 || (ppOut==0 && pnOut==0) );
  3888   3892   
  3889         -  rc = sessionConcatChangeset(bPatch, nLeft, pLeft, &pList);
         3893  +  rc = sessionAddChangeset(pLeft, &pList);
  3890   3894     if( rc==SQLITE_OK ){
  3891         -    rc = sessionConcatChangeset(bPatch, nRight, pRight, &pList);
         3895  +    rc = sessionAddChangeset(pRight, &pList);
  3892   3896     }
         3897  +  bPatch = pLeft->bPatchset || pRight->bPatchset;
  3893   3898   
  3894   3899     /* Create the serialized output changeset based on the contents of the
  3895   3900     ** hash tables attached to the SessionTable objects in list pList. 
  3896   3901     */
  3897   3902     if( rc==SQLITE_OK ){
  3898   3903       SessionTable *pTab;
  3899   3904       SessionBuffer buf = {0, 0, 0};
  3900         -    for(pTab=pList; pTab; pTab=pTab->pNext){
         3905  +    for(pTab=pList; pTab && rc==SQLITE_OK; pTab=pTab->pNext){
  3901   3906         int i;
  3902   3907         if( pTab->nEntry==0 ) continue;
  3903   3908   
  3904   3909         sessionAppendTableHdr(&buf, bPatch, pTab, &rc);
  3905   3910         for(i=0; i<pTab->nChange; i++){
  3906   3911           SessionChange *p;
  3907   3912           for(p=pTab->apChange[i]; p; p=p->pNext){
  3908   3913             sessionAppendByte(&buf, p->op, &rc);
  3909   3914             sessionAppendByte(&buf, p->bIndirect, &rc);
  3910   3915             sessionAppendBlob(&buf, p->aRecord, p->nRecord, &rc);
  3911   3916           }
  3912   3917         }
         3918  +
         3919  +      if( rc==SQLITE_OK && xOutput && buf.nBuf>=SESSIONS_STR_CHUNK_SIZE ){
         3920  +        rc = xOutput(pOut, buf.aBuf, buf.nBuf);
         3921  +        buf.nBuf = 0;
         3922  +      }
  3913   3923       }
  3914   3924   
  3915   3925       if( rc==SQLITE_OK ){
  3916         -      *ppOut = buf.aBuf;
  3917         -      *pnOut = buf.nBuf;
  3918         -    }else{
  3919         -      sqlite3_free(buf.aBuf);
         3926  +      if( xOutput ){
         3927  +        if( buf.nBuf>0 ) rc = xOutput(pOut, buf.aBuf, buf.nBuf);
         3928  +      }else{
         3929  +        *ppOut = buf.aBuf;
         3930  +        *pnOut = buf.nBuf;
         3931  +        buf.aBuf = 0;
         3932  +      }
  3920   3933       }
         3934  +    sqlite3_free(buf.aBuf);
  3921   3935     }
  3922   3936   
  3923   3937     sessionDeleteTable(pList);
  3924   3938     return rc;
  3925   3939   }
         3940  +
         3941  +/* 
         3942  +** Combine two changesets together.
         3943  +*/
         3944  +int sqlite3changeset_concat(
         3945  +  int nLeft,                      /* Number of bytes in lhs input */
         3946  +  void *pLeft,                    /* Lhs input changeset */
         3947  +  int nRight                      /* Number of bytes in rhs input */,
         3948  +  void *pRight,                   /* Rhs input changeset */
         3949  +  int *pnOut,                     /* OUT: Number of bytes in output changeset */
         3950  +  void **ppOut                    /* OUT: changeset (left <concat> right) */
         3951  +){
         3952  +  sqlite3_changeset_iter *pIter1 = 0;
         3953  +  sqlite3_changeset_iter *pIter2 = 0;
         3954  +  int rc;
         3955  +
         3956  +  *pnOut = 0;
         3957  +  *ppOut = 0;
         3958  +  rc = sqlite3changeset_start(&pIter1, nLeft, pLeft);
         3959  +  if( rc==SQLITE_OK ){
         3960  +    rc = sqlite3changeset_start(&pIter2, nRight, pRight);
         3961  +  }
         3962  +  if( rc==SQLITE_OK ){
         3963  +    rc = sessionChangesetConcat(pIter1, pIter2, 0, 0, pnOut, ppOut);
         3964  +  }
         3965  +
         3966  +  sqlite3changeset_finalize(pIter1);
         3967  +  sqlite3changeset_finalize(pIter2);
         3968  +  return rc;
         3969  +}
         3970  +
         3971  +/*
         3972  +** Streaming version of sqlite3changeset_concat().
         3973  +*/
         3974  +int sqlite3changeset_concat_str(
         3975  +  int (*xInputA)(void *pIn, void *pData, int *pnData),
         3976  +  void *pInA,
         3977  +  int (*xInputB)(void *pIn, void *pData, int *pnData),
         3978  +  void *pInB,
         3979  +  int (*xOutput)(void *pOut, const void *pData, int nData),
         3980  +  void *pOut
         3981  +){
         3982  +  sqlite3_changeset_iter *pIter1 = 0;
         3983  +  sqlite3_changeset_iter *pIter2 = 0;
         3984  +  int rc;
         3985  +
         3986  +  rc = sqlite3changeset_start_str(&pIter1, xInputA, pInA);
         3987  +  if( rc==SQLITE_OK ){
         3988  +    rc = sqlite3changeset_start_str(&pIter2, xInputB, pInB);
         3989  +  }
         3990  +  if( rc==SQLITE_OK ){
         3991  +    rc = sessionChangesetConcat(pIter1, pIter2, xOutput, pOut, 0, 0);
         3992  +  }
         3993  +
         3994  +  sqlite3changeset_finalize(pIter1);
         3995  +  sqlite3changeset_finalize(pIter2);
         3996  +  return rc;
         3997  +}
  3926   3998   
  3927   3999   #endif /* SQLITE_ENABLE_SESSION && SQLITE_ENABLE_PREUPDATE_HOOK */

Changes to ext/session/sqlite3session.h.

   756    756     int nA,                         /* Number of bytes in buffer pA */
   757    757     void *pA,                       /* Pointer to buffer containing changeset A */
   758    758     int nB,                         /* Number of bytes in buffer pB */
   759    759     void *pB,                       /* Pointer to buffer containing changeset B */
   760    760     int *pnOut,                     /* OUT: Number of bytes in output changeset */
   761    761     void **ppOut                    /* OUT: Buffer containing output changeset */
   762    762   );
          763  +
          764  +/*
          765  +** Streaming verson of sqlite3changeset_concat().
          766  +*/
          767  +int sqlite3changeset_concat_str(
          768  +  int (*xInputA)(void *pIn, void *pData, int *pnData),
          769  +  void *pInA,
          770  +  int (*xInputB)(void *pIn, void *pData, int *pnData),
          771  +  void *pInB,
          772  +  int (*xOutput)(void *pOut, const void *pData, int nData),
          773  +  void *pOut
          774  +);
   763    775   
   764    776   /*
   765    777   ** CAPI3REF: Apply A Changeset To A Database
   766    778   **
   767    779   ** Apply a changeset to a database. This function attempts to update the
   768    780   ** "main" database attached to handle db with the changes found in the
   769    781   ** changeset passed via the second and third arguments.

Changes to ext/session/test_session.c.

   711    711   static int test_sqlite3changeset_concat(
   712    712     void * clientData,
   713    713     Tcl_Interp *interp,
   714    714     int objc,
   715    715     Tcl_Obj *CONST objv[]
   716    716   ){
   717    717     int rc;                         /* Return code from changeset_invert() */
   718         -  void *aLeft;                    /* Input changeset */
   719         -  int nLeft;                      /* Size of buffer aChangeset in bytes */
   720         -  void *aRight;                   /* Input changeset */
   721         -  int nRight;                     /* Size of buffer aChangeset in bytes */
   722         -  void *aOut;                     /* Output changeset */
   723         -  int nOut;                       /* Size of buffer aOut in bytes */
          718  +
          719  +  TestStreamInput sLeft;          /* Input stream */
          720  +  TestStreamInput sRight;         /* Input stream */
          721  +  TestSessionsBlob sOut = {0,0};  /* Output blob */
   724    722   
   725    723     if( objc!=3 ){
   726    724       Tcl_WrongNumArgs(interp, 1, objv, "LEFT RIGHT");
   727    725       return TCL_ERROR;
   728    726     }
   729         -  aLeft = (void *)Tcl_GetByteArrayFromObj(objv[1], &nLeft);
   730         -  aRight = (void *)Tcl_GetByteArrayFromObj(objv[2], &nRight);
   731    727   
   732         -  rc = sqlite3changeset_concat(nLeft, aLeft, nRight, aRight, &nOut, &aOut);
          728  +  memset(&sLeft, 0, sizeof(sLeft));
          729  +  memset(&sRight, 0, sizeof(sRight));
          730  +  sLeft.aData = Tcl_GetByteArrayFromObj(objv[1], &sLeft.nData);
          731  +  sRight.aData = Tcl_GetByteArrayFromObj(objv[2], &sRight.nData);
          732  +  sLeft.nStream = test_tcl_integer(interp, SESSION_STREAM_TCL_VAR);
          733  +  sRight.nStream = sLeft.nStream;
          734  +
          735  +  if( sLeft.nStream>0 ){
          736  +    rc = sqlite3changeset_concat_str(
          737  +        testStreamInput, (void*)&sLeft,
          738  +        testStreamInput, (void*)&sRight,
          739  +        testSessionsOutput, (void*)&sOut
          740  +    );
          741  +  }else{
          742  +    rc = sqlite3changeset_concat(
          743  +        sLeft.nData, sLeft.aData, sRight.nData, sRight.aData, &sOut.n, &sOut.p
          744  +    );
          745  +  }
          746  +
   733    747     if( rc!=SQLITE_OK ){
   734         -    return test_session_error(interp, rc);
          748  +    rc = test_session_error(interp, rc);
          749  +  }else{
          750  +    Tcl_SetObjResult(interp,Tcl_NewByteArrayObj((unsigned char*)sOut.p,sOut.n));
   735    751     }
   736         -  Tcl_SetObjResult(interp, Tcl_NewByteArrayObj((unsigned char *)aOut, nOut));
   737         -  sqlite3_free(aOut);
   738         -  return TCL_OK;
          752  +  sqlite3_free(sOut.p);
          753  +  return rc;
   739    754   }
   740    755   
   741    756   /*
   742    757   ** sqlite3session_foreach VARNAME CHANGESET SCRIPT
   743    758   */
   744    759   static int test_sqlite3session_foreach(
   745    760     void * clientData,