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Overview
Comment:Fix some missing comments and other issues with session module code.
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Files: files | file ages | folders
SHA1: 20d7c280235201e519f296372f269e7cecda24da
User & Date: dan 2011-04-18 12:05:03.122
Context
2011-04-18
15:47
Fix further missing comments and other minor issues in the session module code. (check-in: 99f0f35092 user: dan tags: sessions)
12:05
Fix some missing comments and other issues with session module code. (check-in: 20d7c28023 user: dan tags: sessions)
07:36
Further coverage tests for the session module. (check-in: 69a01c708b user: dan tags: sessions)
Changes
Unified Diff Ignore Whitespace Patch
Changes to ext/session/sqlite3session.c.
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*/

/*
** For each row modified during a session, there exists a single instance of
** this structure stored in a SessionTable.aChange[] hash table.
*/
struct SessionChange {
  int bInsert;                    /* True if row was inserted this session */
  int bIndirect;                  /* True if this change is "indirect" */
  int nRecord;                    /* Number of bytes in buffer aRecord[] */
  u8 *aRecord;                    /* Buffer containing old.* record */
  SessionChange *pNext;           /* For hash-table collisions */
};

/*







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*/

/*
** For each row modified during a session, there exists a single instance of
** this structure stored in a SessionTable.aChange[] hash table.
*/
struct SessionChange {
  int op;                         /* One of UPDATE, DELETE, INSERT */
  int bIndirect;                  /* True if this change is "indirect" */
  int nRecord;                    /* Number of bytes in buffer aRecord[] */
  u8 *aRecord;                    /* Buffer containing old.* record */
  SessionChange *pNext;           /* For hash-table collisions */
};

/*
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    if( aBuf ) aBuf[0] = '\0';
  }

  *pnWrite += nByte;
  return SQLITE_OK;
}
















#define HASH_APPEND(hash, add) ((hash) << 3) ^ (hash) ^ (unsigned int)(add)





static unsigned int sessionHashAppendI64(unsigned int h, i64 i){
  h = HASH_APPEND(h, i & 0xFFFFFFFF);
  return HASH_APPEND(h, (i>>32)&0xFFFFFFFF);
}





static unsigned int sessionHashAppendBlob(unsigned int h, int n, const u8 *z){
  int i;
  for(i=0; i<n; i++) h = HASH_APPEND(h, z[i]);
  return h;
}









/*
** This function may only be called from within a pre-update callback.
** It calculates a hash based on the primary key values of the old.* or 
** new.* row currently available. The value returned is guaranteed to


** be less than pTab->nBucket.



*/
static unsigned int sessionPreupdateHash(
  sqlite3 *db,                    /* Database handle */
  SessionTable *pTab,             /* Session table handle */
  int bNew,                       /* True to hash the new.* PK */
  int *piHash,                    /* OUT: Hash value */
  int *pbNullPK
){
  unsigned int h = 0;             /* Hash value to return */
  int i;                          /* Used to iterate through columns */

  assert( *pbNullPK==0 );
  assert( pTab->nCol==sqlite3_preupdate_count(db) );
  for(i=0; i<pTab->nCol; i++){
    if( pTab->abPK[i] ){
      int rc;
      int eType;
      sqlite3_value *pVal;

      if( bNew ){
        rc = sqlite3_preupdate_new(db, i, &pVal);
      }else{
        rc = sqlite3_preupdate_old(db, i, &pVal);
      }
      if( rc!=SQLITE_OK ) return rc;

      eType = sqlite3_value_type(pVal);
      h = HASH_APPEND(h, eType);
      if( eType==SQLITE_INTEGER || eType==SQLITE_FLOAT ){
        i64 iVal;
        if( eType==SQLITE_INTEGER ){
          iVal = sqlite3_value_int64(pVal);
        }else{
          double rVal = sqlite3_value_double(pVal);
          assert( sizeof(iVal)==8 && sizeof(rVal)==8 );







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    if( aBuf ) aBuf[0] = '\0';
  }

  *pnWrite += nByte;
  return SQLITE_OK;
}

/*
** This macro is used to calculate hash key values for data structures. In
** order to use this macro, the entire data structure must be represented
** as a series of unsigned integers. In order to calculate a hash-key value
** for a data structure represented as three such integers, the macro may
** then be used as follows:
**
**    int hash_key_value;
**    hash_key_value = HASH_APPEND(0, <value 1>);
**    hash_key_value = HASH_APPEND(hash_key_value, <value 2>);
**    hash_key_value = HASH_APPEND(hash_key_value, <value 3>);
**
** In practice, the data structures this macro is used for are the primary
** key values of modified rows.
*/
#define HASH_APPEND(hash, add) ((hash) << 3) ^ (hash) ^ (unsigned int)(add)

/*
** Append the hash of the 64-bit integer passed as the second argument to the
** hash-key value passed as the first. Return the new hash-key value.
*/
static unsigned int sessionHashAppendI64(unsigned int h, i64 i){
  h = HASH_APPEND(h, i & 0xFFFFFFFF);
  return HASH_APPEND(h, (i>>32)&0xFFFFFFFF);
}

/*
** Append the hash of the blob passed via the second and third arguments to 
** the hash-key value passed as the first. Return the new hash-key value.
*/
static unsigned int sessionHashAppendBlob(unsigned int h, int n, const u8 *z){
  int i;
  for(i=0; i<n; i++) h = HASH_APPEND(h, z[i]);
  return h;
}

/*
** Append the hash of the data type passed as the second argument to the
** hash-key value passed as the first. Return the new hash-key value.
*/
static unsigned int sessionHashAppendType(unsigned int h, int eType){
  return HASH_APPEND(h, eType);
}

/*
** This function may only be called from within a pre-update callback.
** It calculates a hash based on the primary key values of the old.* or 
** new.* row currently available and, assuming no error occurs, writes it to
** *piHash before returning. If the primary key contains one or more NULL
** values, *pbNullPK is set to true before returning.
**
** If an error occurs, an SQLite error code is returned and the final values
** of *piHash asn *pbNullPK are undefined. Otherwise, SQLITE_OK is returned
** and the output variables are set as described above.
*/
static int sessionPreupdateHash(
  sqlite3 *db,                    /* Database handle */
  SessionTable *pTab,             /* Session table handle */
  int bNew,                       /* True to hash the new.* PK */
  int *piHash,                    /* OUT: Hash value */
  int *pbNullPK                   /* OUT: True if there are NULL values in PK */
){
  unsigned int h = 0;             /* Hash value to return */
  int i;                          /* Used to iterate through columns */

  assert( *pbNullPK==0 );
  assert( pTab->nCol==sqlite3_preupdate_count(db) );
  for(i=0; i<pTab->nCol; i++){
    if( pTab->abPK[i] ){
      int rc;
      int eType;
      sqlite3_value *pVal;

      if( bNew ){
        rc = sqlite3_preupdate_new(db, i, &pVal);
      }else{
        rc = sqlite3_preupdate_old(db, i, &pVal);
      }
      if( rc!=SQLITE_OK ) return rc;

      eType = sqlite3_value_type(pVal);
      h = sessionHashAppendType(h, eType);
      if( eType==SQLITE_INTEGER || eType==SQLITE_FLOAT ){
        i64 iVal;
        if( eType==SQLITE_INTEGER ){
          iVal = sqlite3_value_int64(pVal);
        }else{
          double rVal = sqlite3_value_double(pVal);
          assert( sizeof(iVal)==8 && sizeof(rVal)==8 );
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          z = (const u8 *)sqlite3_value_blob(pVal);
        }
        if( !z ) return SQLITE_NOMEM;
        h = sessionHashAppendBlob(h, sqlite3_value_bytes(pVal), z);
      }else{
        assert( eType==SQLITE_NULL );
        *pbNullPK = 1;
        return SQLITE_OK;
      }
    }
  }

  *piHash = (h % pTab->nChange);
  return SQLITE_OK;
}







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          z = (const u8 *)sqlite3_value_blob(pVal);
        }
        if( !z ) return SQLITE_NOMEM;
        h = sessionHashAppendBlob(h, sqlite3_value_bytes(pVal), z);
      }else{
        assert( eType==SQLITE_NULL );
        *pbNullPK = 1;

      }
    }
  }

  *piHash = (h % pTab->nChange);
  return SQLITE_OK;
}
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  if( e==SQLITE_NULL ) return 1;
  if( e==SQLITE_INTEGER || e==SQLITE_FLOAT ) return 9;
  return sessionVarintGet(&a[1], &n) + 1 + n;
}

/*
** Based on the primary key values stored in change aRecord, calculate a
** hash key, assuming the has table has nBucket buckets. The hash keys
** calculated by this function are compatible with those calculated by
** sessionPreupdateHash().
*/
static unsigned int sessionChangeHash(
  SessionTable *pTab,             /* Table handle */
  u8 *aRecord,                    /* Change record */
  int nBucket                     /* Assume this many buckets in hash table */







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  if( e==SQLITE_NULL ) return 1;
  if( e==SQLITE_INTEGER || e==SQLITE_FLOAT ) return 9;
  return sessionVarintGet(&a[1], &n) + 1 + n;
}

/*
** Based on the primary key values stored in change aRecord, calculate a
** hash key. Assume the has table has nBucket buckets. The hash keys
** calculated by this function are compatible with those calculated by
** sessionPreupdateHash().
*/
static unsigned int sessionChangeHash(
  SessionTable *pTab,             /* Table handle */
  u8 *aRecord,                    /* Change record */
  int nBucket                     /* Assume this many buckets in hash table */
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         || eType==SQLITE_TEXT || eType==SQLITE_BLOB 
         || eType==SQLITE_NULL || eType==0 
    );
    assert( !isPK || (eType!=0 && eType!=SQLITE_NULL) );

    if( isPK ){
      a++;
      h = HASH_APPEND(h, eType);
      if( eType==SQLITE_INTEGER || eType==SQLITE_FLOAT ){
        h = sessionHashAppendI64(h, sessionGetI64(a));
        a += 8;
      }else{
        int n; 
        a += sessionVarintGet(a, &n);
        h = sessionHashAppendBlob(h, n, a);
        a += n;
      }
    }else{
      a += sessionSerialLen(a);
    }
  }
  return (h % nBucket);
}







static int sessionChangeEqual(
  SessionTable *pTab,
  u8 *aLeft,                      /* Change record */
  u8 *aRight                      /* Change record */
){
  u8 *a1 = aLeft;
  u8 *a2 = aRight;
  int i;

  for(i=0; i<pTab->nCol; i++){
    int n1 = sessionSerialLen(a1);
    int n2 = sessionSerialLen(a2);

    if( pTab->abPK[i] && (n1!=n2 || memcmp(a1, a2, n1)) ){
      return 0;
    }
    a1 += n1;
    a2 += n2;
  }

  return 1;
}














static void sessionMergeRecord(
  u8 **paOut, 
  SessionTable *pTab, 

  u8 *aLeft,
  u8 *aRight
){
  u8 *a1 = aLeft;
  u8 *a2 = aRight;
  u8 *aOut = *paOut;
  int i;

  for(i=0; i<pTab->nCol; i++){
    int n1 = sessionSerialLen(a1);
    int n2 = sessionSerialLen(a2);
    if( *a2 ){
      memcpy(aOut, a2, n2);
      aOut += n2;
    }else{
      memcpy(aOut, a1, n1);
      aOut += n1;
    }
    a1 += n1;
    a2 += n2;
  }

  *paOut = aOut;
}















static u8 *sessionMergeValue(
  u8 **paOne,
  u8 **paTwo,
  int *pnVal
){
  u8 *a1 = *paOne;
  u8 *a2 = *paTwo;
  u8 *pRet = 0;
  int n1;

  assert( a1 );







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         || eType==SQLITE_TEXT || eType==SQLITE_BLOB 
         || eType==SQLITE_NULL || eType==0 
    );
    assert( !isPK || (eType!=0 && eType!=SQLITE_NULL) );

    if( isPK ){
      a++;
      h = sessionHashAppendType(h, eType);
      if( eType==SQLITE_INTEGER || eType==SQLITE_FLOAT ){
        h = sessionHashAppendI64(h, sessionGetI64(a));
        a += 8;
      }else{
        int n; 
        a += sessionVarintGet(a, &n);
        h = sessionHashAppendBlob(h, n, a);
        a += n;
      }
    }else{
      a += sessionSerialLen(a);
    }
  }
  return (h % nBucket);
}

/*
** Arguments aLeft and aRight are pointers to change records for table pTab.
** This function returns true if the two records apply to the same row (i.e.
** have the same values stored in the primary key columns), or false 
** otherwise.
*/
static int sessionChangeEqual(
  SessionTable *pTab,             /* Table used for PK definition */
  u8 *aLeft,                      /* Change record */
  u8 *aRight                      /* Change record */
){
  u8 *a1 = aLeft;                 /* Cursor to iterate through aLeft */
  u8 *a2 = aRight;                /* Cursor to iterate through aRight */
  int iCol;                       /* Used to iterate through table columns */

  for(iCol=0; iCol<pTab->nCol; iCol++){
    int n1 = sessionSerialLen(a1);
    int n2 = sessionSerialLen(a2);

    if( pTab->abPK[iCol] && (n1!=n2 || memcmp(a1, a2, n1)) ){
      return 0;
    }
    a1 += n1;
    a2 += n2;
  }

  return 1;
}

/*
** Arguments aLeft and aRight both point to buffers containing change
** records with nCol columns. This function "merges" the two records into
** a single records which is written to the buffer at *paOut. *paOut is
** then set to point to one byte after the last byte written before 
** returning.
**
** The merging of records is done as follows: For each column, if the 
** aRight record contains a value for the column, copy the value from
** their. Otherwise, if aLeft contains a value, copy it. If neither
** record contains a value for a given column, then neither does the
** output record.
*/
static void sessionMergeRecord(
  u8 **paOut, 

  int nCol,
  u8 *aLeft,
  u8 *aRight
){
  u8 *a1 = aLeft;                 /* Cursor used to iterate through aLeft */
  u8 *a2 = aRight;                /* Cursor used to iterate through aRight */
  u8 *aOut = *paOut;              /* Output cursor */
  int iCol;                       /* Used to iterate from 0 to nCol */

  for(iCol=0; iCol<nCol; iCol++){
    int n1 = sessionSerialLen(a1);
    int n2 = sessionSerialLen(a2);
    if( *a2 ){
      memcpy(aOut, a2, n2);
      aOut += n2;
    }else{
      memcpy(aOut, a1, n1);
      aOut += n1;
    }
    a1 += n1;
    a2 += n2;
  }

  *paOut = aOut;
}

/*
** This is a helper function used by sessionMergeUpdate().
**
** When this function is called, both *paOne and *paTwo point to a value 
** within a change record. Before it returns, both have been advanced so 
** as to point to the next value in the record.
**
** If, when this function is called, *paTwo points to a valid value (i.e.
** *paTwo[0] is not 0x00 - the "no value" placeholder), a copy of the *paOne
** pointer is returned and *pnVal is set to the number of bytes in the 
** serialized value. Otherwise, a copy of *paOne is returned and *pnVal
** set to the number of bytes in the value at *paOne. If *paOne points
** to the "no value" placeholder, *pnVal is set to 1.
*/
static u8 *sessionMergeValue(
  u8 **paOne,                     /* IN/OUT: Left-hand buffer pointer */
  u8 **paTwo,                     /* IN/OUT: Right-hand buffer pointer */
  int *pnVal                      /* OUT: Bytes in returned value */
){
  u8 *a1 = *paOne;
  u8 *a2 = *paTwo;
  u8 *pRet = 0;
  int n1;

  assert( a1 );
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    pRet = a1;
  }
  *paOne = &a1[n1];

  return pRet;
}





static int sessionMergeUpdate(
  u8 **paOut, 
  SessionTable *pTab, 
  u8 *aOldRecord1,
  u8 *aOldRecord2,
  u8 *aNewRecord1,
  u8 *aNewRecord2
){
  u8 *aOld1 = aOldRecord1;
  u8 *aOld2 = aOldRecord2;
  u8 *aNew1 = aNewRecord1;
  u8 *aNew2 = aNewRecord2;

  u8 *aOut = *paOut;







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    pRet = a1;
  }
  *paOne = &a1[n1];

  return pRet;
}

/*
** This function is used by changeset_concat() to merge two UPDATE changes
** on the same row.
*/
static int sessionMergeUpdate(
  u8 **paOut,                     /* IN/OUT: Pointer to output buffer */
  SessionTable *pTab,             /* Table change pertains to */
  u8 *aOldRecord1,                /* old.* record for first change */
  u8 *aOldRecord2,                /* old.* record for second change */
  u8 *aNewRecord1,                /* new.* record for first change */
  u8 *aNewRecord2                 /* new.* record for second change */
){
  u8 *aOld1 = aOldRecord1;
  u8 *aOld2 = aOldRecord2;
  u8 *aNew1 = aNewRecord1;
  u8 *aNew2 = aNewRecord2;

  u8 *aOut = *paOut;
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){
  int i;
  u8 *a = pChange->aRecord;

  *pbEqual = 0;

  for(i=0; i<pTab->nCol; i++){
    int eType = *a++;
    if( !pTab->abPK[i] ){
      switch( eType ){
        case SQLITE_INTEGER: 
        case SQLITE_FLOAT:
          a += 8;
          break;

        case SQLITE_TEXT: 
        case SQLITE_BLOB: {
          int n;
          a += sessionVarintGet(a, &n);
          a += n;
          break;
        }
      }
    }else{
      sqlite3_value *pVal;        /* Value returned by preupdate_new/old */
      int rc;                     /* Error code from preupdate_new/old */


      /* The following calls to preupdate_new() and preupdate_old() can not
      ** fail. This is because they cache their return values, and by the
      ** time control flows to here they have already been called once from
      ** within sessionPreupdateHash(). The first two asserts below verify
      ** this (that the method has already been called). */
      if( bNew ){







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){
  int i;
  u8 *a = pChange->aRecord;

  *pbEqual = 0;

  for(i=0; i<pTab->nCol; i++){

    if( !pTab->abPK[i] ){









      a += sessionSerialLen(a);




    }else{
      sqlite3_value *pVal;        /* Value returned by preupdate_new/old */
      int rc;                     /* Error code from preupdate_new/old */
      int eType = *a++;           /* Type of value from change record */

      /* The following calls to preupdate_new() and preupdate_old() can not
      ** fail. This is because they cache their return values, and by the
      ** time control flows to here they have already been called once from
      ** within sessionPreupdateHash(). The first two asserts below verify
      ** this (that the method has already been called). */
      if( bNew ){
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      }

      /* Add the change to the hash-table */
      if( pSession->bIndirect || sqlite3_preupdate_depth(pSession->db) ){
        pChange->bIndirect = 1;
      }
      pChange->nRecord = nByte;
      pChange->bInsert = (op==SQLITE_INSERT);
      pChange->pNext = pTab->apChange[iHash];
      pTab->apChange[iHash] = pChange;

    }else if( pC->bIndirect ){
      /* If the existing change is considered "indirect", but this current
      ** change is "direct", mark the change object as direct. */
      if( sqlite3_preupdate_depth(pSession->db)==0 && pSession->bIndirect==0 ){







|







999
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1001
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      }

      /* Add the change to the hash-table */
      if( pSession->bIndirect || sqlite3_preupdate_depth(pSession->db) ){
        pChange->bIndirect = 1;
      }
      pChange->nRecord = nByte;
      pChange->op = op;
      pChange->pNext = pTab->apChange[iHash];
      pTab->apChange[iHash] = pChange;

    }else if( pC->bIndirect ){
      /* If the existing change is considered "indirect", but this current
      ** change is "direct", mark the change object as direct. */
      if( sqlite3_preupdate_depth(pSession->db)==0 && pSession->bIndirect==0 ){
1602
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1604
1605
1606
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1608

1609
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1626
      for(i=0; i<pTab->nChange && rc==SQLITE_OK; i++){
        SessionChange *p;         /* Used to iterate through changes */

        for(p=pTab->apChange[i]; rc==SQLITE_OK && p; p=p->pNext){
          rc = sessionSelectBind(pSel, nCol, abPK, p);
          if( rc!=SQLITE_OK ) continue;
          if( sqlite3_step(pSel)==SQLITE_ROW ){

            int iCol;
            if( p->bInsert ){
              sessionAppendByte(&buf, SQLITE_INSERT, &rc);
              sessionAppendByte(&buf, p->bIndirect, &rc);
              for(iCol=0; iCol<nCol; iCol++){
                sessionAppendCol(&buf, pSel, iCol, &rc);
              }
            }else{
              rc = sessionAppendUpdate(&buf, pSel, p, abPK);
            }
          }else if( !p->bInsert ){
            /* A DELETE change */
            sessionAppendByte(&buf, SQLITE_DELETE, &rc);
            sessionAppendByte(&buf, p->bIndirect, &rc);
            sessionAppendBlob(&buf, p->aRecord, p->nRecord, &rc);
          }
          if( rc==SQLITE_OK ){
            rc = sqlite3_reset(pSel);







>
|
<








|







1663
1664
1665
1666
1667
1668
1669
1670
1671

1672
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      for(i=0; i<pTab->nChange && rc==SQLITE_OK; i++){
        SessionChange *p;         /* Used to iterate through changes */

        for(p=pTab->apChange[i]; rc==SQLITE_OK && p; p=p->pNext){
          rc = sessionSelectBind(pSel, nCol, abPK, p);
          if( rc!=SQLITE_OK ) continue;
          if( sqlite3_step(pSel)==SQLITE_ROW ){
            if( p->op==SQLITE_INSERT ){
              int iCol;

              sessionAppendByte(&buf, SQLITE_INSERT, &rc);
              sessionAppendByte(&buf, p->bIndirect, &rc);
              for(iCol=0; iCol<nCol; iCol++){
                sessionAppendCol(&buf, pSel, iCol, &rc);
              }
            }else{
              rc = sessionAppendUpdate(&buf, pSel, p, abPK);
            }
          }else if( p->op!=SQLITE_INSERT ){
            /* A DELETE change */
            sessionAppendByte(&buf, SQLITE_DELETE, &rc);
            sessionAppendByte(&buf, p->bIndirect, &rc);
            sessionAppendBlob(&buf, p->aRecord, p->nRecord, &rc);
          }
          if( rc==SQLITE_OK ){
            rc = sqlite3_reset(pSel);
2780
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2783
2784
2785
2786
2787
2788
2789
2790
2791
2792
2793
2794
2795
2796
2797
2798
2799

  if( !pExist ){
    pNew = (SessionChange *)sqlite3_malloc(sizeof(SessionChange));
    if( !pNew ){
      return SQLITE_NOMEM;
    }
    memset(pNew, 0, sizeof(SessionChange));
    pNew->bInsert = op2;
    pNew->bIndirect = bIndirect;
    pNew->nRecord = nRec;
    pNew->aRecord = aRec;
  }else{
    int op1 = pExist->bInsert;

    /* 
    **   op1=INSERT, op2=INSERT      ->      Unsupported. Discard op2.
    **   op1=INSERT, op2=UPDATE      ->      INSERT.
    **   op1=INSERT, op2=DELETE      ->      (none)
    **
    **   op1=UPDATE, op2=INSERT      ->      Unsupported. Discard op2.







|




|







2841
2842
2843
2844
2845
2846
2847
2848
2849
2850
2851
2852
2853
2854
2855
2856
2857
2858
2859
2860

  if( !pExist ){
    pNew = (SessionChange *)sqlite3_malloc(sizeof(SessionChange));
    if( !pNew ){
      return SQLITE_NOMEM;
    }
    memset(pNew, 0, sizeof(SessionChange));
    pNew->op = op2;
    pNew->bIndirect = bIndirect;
    pNew->nRecord = nRec;
    pNew->aRecord = aRec;
  }else{
    int op1 = pExist->op;

    /* 
    **   op1=INSERT, op2=INSERT      ->      Unsupported. Discard op2.
    **   op1=INSERT, op2=UPDATE      ->      INSERT.
    **   op1=INSERT, op2=DELETE      ->      (none)
    **
    **   op1=UPDATE, op2=INSERT      ->      Unsupported. Discard op2.
2826
2827
2828
2829
2830
2831
2832
2833
2834
2835
2836
2837
2838
2839
2840
2841
2842
2843
2844
2845
2846
2847
2848
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2851
2852
2853
2854
2855
2856
2857
2858
2859
2860
2861
2862
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2864
      memset(pNew, 0, sizeof(SessionChange));
      pNew->bIndirect = (bIndirect && pExist->bIndirect);
      aCsr = pNew->aRecord = (u8 *)&pNew[1];

      if( op1==SQLITE_INSERT ){             /* INSERT + UPDATE */
        u8 *a1 = aRec;
        assert( op2==SQLITE_UPDATE );
        pNew->bInsert = SQLITE_INSERT;
        sessionReadRecord(&a1, pTab->nCol, 0);
        sessionMergeRecord(&aCsr, pTab, pExist->aRecord, a1);
      }else if( op1==SQLITE_DELETE ){       /* DELETE + INSERT */
        assert( op2==SQLITE_INSERT );
        pNew->bInsert = SQLITE_UPDATE;
        if( 0==sessionMergeUpdate(&aCsr, pTab, pExist->aRecord, 0, aRec, 0) ){
          sqlite3_free(pNew);
          pNew = 0;
        }
      }else if( op2==SQLITE_UPDATE ){       /* UPDATE + UPDATE */
        assert( op1==SQLITE_UPDATE );
        u8 *a1 = pExist->aRecord;
        u8 *a2 = aRec;
        sessionReadRecord(&a1, pTab->nCol, 0);
        sessionReadRecord(&a2, pTab->nCol, 0);
        pNew->bInsert = SQLITE_UPDATE;
        if( 0==sessionMergeUpdate(&aCsr, pTab, aRec, pExist->aRecord, a1, a2) ){
          sqlite3_free(pNew);
          pNew = 0;
        }
      }else{                                /* UPDATE + DELETE */
        assert( op1==SQLITE_UPDATE && op2==SQLITE_DELETE );
        pNew->bInsert = SQLITE_DELETE;
        sessionMergeRecord(&aCsr, pTab, aRec, pExist->aRecord);
      }

      if( pNew ){
        pNew->nRecord = (aCsr - pNew->aRecord);
      }
      sqlite3_free(pExist);
    }







|

|


|










|






|
|







2887
2888
2889
2890
2891
2892
2893
2894
2895
2896
2897
2898
2899
2900
2901
2902
2903
2904
2905
2906
2907
2908
2909
2910
2911
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
      memset(pNew, 0, sizeof(SessionChange));
      pNew->bIndirect = (bIndirect && pExist->bIndirect);
      aCsr = pNew->aRecord = (u8 *)&pNew[1];

      if( op1==SQLITE_INSERT ){             /* INSERT + UPDATE */
        u8 *a1 = aRec;
        assert( op2==SQLITE_UPDATE );
        pNew->op = SQLITE_INSERT;
        sessionReadRecord(&a1, pTab->nCol, 0);
        sessionMergeRecord(&aCsr, pTab->nCol, pExist->aRecord, a1);
      }else if( op1==SQLITE_DELETE ){       /* DELETE + INSERT */
        assert( op2==SQLITE_INSERT );
        pNew->op = SQLITE_UPDATE;
        if( 0==sessionMergeUpdate(&aCsr, pTab, pExist->aRecord, 0, aRec, 0) ){
          sqlite3_free(pNew);
          pNew = 0;
        }
      }else if( op2==SQLITE_UPDATE ){       /* UPDATE + UPDATE */
        assert( op1==SQLITE_UPDATE );
        u8 *a1 = pExist->aRecord;
        u8 *a2 = aRec;
        sessionReadRecord(&a1, pTab->nCol, 0);
        sessionReadRecord(&a2, pTab->nCol, 0);
        pNew->op = SQLITE_UPDATE;
        if( 0==sessionMergeUpdate(&aCsr, pTab, aRec, pExist->aRecord, a1, a2) ){
          sqlite3_free(pNew);
          pNew = 0;
        }
      }else{                                /* UPDATE + DELETE */
        assert( op1==SQLITE_UPDATE && op2==SQLITE_DELETE );
        pNew->op = SQLITE_DELETE;
        sessionMergeRecord(&aCsr, pTab->nCol, aRec, pExist->aRecord);
      }

      if( pNew ){
        pNew->nRecord = (aCsr - pNew->aRecord);
      }
      sqlite3_free(pExist);
    }
3002
3003
3004
3005
3006
3007
3008
3009
3010
3011
3012
3013
3014
3015
3016
      int i;
      if( pTab->nEntry==0 ) continue;

      sessionAppendTableHdr(&buf, pTab, &rc);
      for(i=0; i<pTab->nChange; i++){
        SessionChange *p;
        for(p=pTab->apChange[i]; p; p=p->pNext){
          sessionAppendByte(&buf, p->bInsert, &rc);
          sessionAppendByte(&buf, p->bIndirect, &rc);
          sessionAppendBlob(&buf, p->aRecord, p->nRecord, &rc);
        }
      }
    }

    if( rc==SQLITE_OK ){







|







3063
3064
3065
3066
3067
3068
3069
3070
3071
3072
3073
3074
3075
3076
3077
      int i;
      if( pTab->nEntry==0 ) continue;

      sessionAppendTableHdr(&buf, pTab, &rc);
      for(i=0; i<pTab->nChange; i++){
        SessionChange *p;
        for(p=pTab->apChange[i]; p; p=p->pNext){
          sessionAppendByte(&buf, p->op, &rc);
          sessionAppendByte(&buf, p->bIndirect, &rc);
          sessionAppendBlob(&buf, p->aRecord, p->nRecord, &rc);
        }
      }
    }

    if( rc==SQLITE_OK ){