diff options
Diffstat (limited to 'ext/session/sqlite3session.c')
| -rw-r--r-- | ext/session/sqlite3session.c | 37 |
1 files changed, 27 insertions, 10 deletions
diff --git a/ext/session/sqlite3session.c b/ext/session/sqlite3session.c index b86c635ed..69d67817b 100644 --- a/ext/session/sqlite3session.c +++ b/ext/session/sqlite3session.c @@ -498,9 +498,9 @@ static unsigned int sessionChangeHash( */ static int sessionChangeEqual( SessionTable *pTab, /* Table used for PK definition */ - int bLeftPkOnly, + int bLeftPkOnly, /* True if aLeft[] contains PK fields only */ u8 *aLeft, /* Change record */ - int bRightPkOnly, + int bRightPkOnly, /* True if aRight[] contains PK fields only */ u8 *aRight /* Change record */ ){ u8 *a1 = aLeft; /* Cursor to iterate through aLeft */ @@ -613,7 +613,7 @@ static u8 *sessionMergeValue( static int sessionMergeUpdate( u8 **paOut, /* IN/OUT: Pointer to output buffer */ SessionTable *pTab, /* Table change pertains to */ - int bPatchset, + int bPatchset, /* True if records are patchset records */ u8 *aOldRecord1, /* old.* record for first change */ u8 *aOldRecord2, /* old.* record for second change */ u8 *aNewRecord1, /* new.* record for first change */ @@ -1576,11 +1576,16 @@ static int sessionAppendUpdate( return rc; } +/* +** Append a DELETE change to the buffer passed as the first argument. Use +** the changeset format if argument bPatchset is zero, or the patchset +** format otherwise. +*/ static int sessionAppendDelete( SessionBuffer *pBuf, /* Buffer to append to */ int bPatchset, /* True for "patchset", 0 for "changeset" */ - sqlite3_stmt *pStmt, /* Statement handle pointing at new row */ SessionChange *p, /* Object containing old values */ + int nCol, /* Number of columns in table */ u8 *abPK /* Boolean array - true for PK columns */ ){ int rc = SQLITE_OK; @@ -1591,7 +1596,6 @@ static int sessionAppendDelete( if( bPatchset==0 ){ sessionAppendBlob(pBuf, p->aRecord, p->nRecord, &rc); }else{ - int nCol = sqlite3_column_count(pStmt); int i; u8 *a = p->aRecord; for(i=0; i<nCol; i++){ @@ -1747,10 +1751,10 @@ static int sessionSelectBind( ** SQLite error code before returning. */ static void sessionAppendTableHdr( - SessionBuffer *pBuf, - int bPatchset, - SessionTable *pTab, - int *pRc + SessionBuffer *pBuf, /* Append header to this buffer */ + int bPatchset, /* Use the patchset format if true */ + SessionTable *pTab, /* Table object to append header for */ + int *pRc /* IN/OUT: Error code */ ){ /* Write a table header */ sessionAppendByte(pBuf, (bPatchset ? 'P' : 'T'), pRc); @@ -1759,6 +1763,16 @@ static void sessionAppendTableHdr( sessionAppendBlob(pBuf, (u8 *)pTab->zName, (int)strlen(pTab->zName)+1, pRc); } +/* +** Generate either a changeset (if argument bPatchset is zero) or a patchset +** (if it is non-zero) based on the current contents of the session object +** passed as the first argument. +** +** If no error occurs, SQLITE_OK is returned and the new changeset/patchset +** stored in output variables *pnChangeset and *ppChangeset. Or, if an error +** occurs, an SQLite error code is returned and both output variables set +** to 0. +*/ int sessionGenerateChangeset( sqlite3_session *pSession, /* Session object */ int bPatchset, /* True for patchset, false for changeset */ @@ -1827,7 +1841,7 @@ int sessionGenerateChangeset( rc = sessionAppendUpdate(&buf, bPatchset, pSel, p, abPK); } }else if( p->op!=SQLITE_INSERT ){ - rc = sessionAppendDelete(&buf, bPatchset, pSel, p, abPK); + rc = sessionAppendDelete(&buf, bPatchset, p, nCol, abPK); } if( rc==SQLITE_OK ){ rc = sqlite3_reset(pSel); @@ -1965,6 +1979,9 @@ int sqlite3changeset_start( ** When this function is called, *paChange points to the start of the record ** to deserialize. Assuming no error occurs, *paChange is set to point to ** one byte after the end of the same record before this function returns. +** If the argument abPK is NULL, then the record contains nCol values. Or, +** if abPK is other than NULL, then the record contains only the PK fields +** (in other words, it is a patchset DELETE record). ** ** If successful, each element of the apOut[] array (allocated by the caller) ** is set to point to an sqlite3_value object containing the value read |