diff options
Diffstat (limited to 'ext/session/sqlite3session.c')
| -rw-r--r-- | ext/session/sqlite3session.c | 708 |
1 files changed, 558 insertions, 150 deletions
diff --git a/ext/session/sqlite3session.c b/ext/session/sqlite3session.c index 049154923..80783805c 100644 --- a/ext/session/sqlite3session.c +++ b/ext/session/sqlite3session.c @@ -119,6 +119,18 @@ struct sqlite3_changeset_iter { ** The data associated with each hash-table entry is a structure containing ** a subset of the initial values that the modified row contained at the ** start of the session. Or no initial values if the row was inserted. +** +** pDfltStmt: +** This is only used by the sqlite3changegroup_xxx() APIs, not by +** regular sqlite3_session objects. It is a SELECT statement that +** selects the default value for each table column. For example, +** if the table is +** +** CREATE TABLE xx(a DEFAULT 1, b, c DEFAULT 'abc') +** +** then this variable is the compiled version of: +** +** SELECT 1, NULL, 'abc' */ struct SessionTable { SessionTable *pNext; @@ -127,10 +139,12 @@ struct SessionTable { int bStat1; /* True if this is sqlite_stat1 */ int bRowid; /* True if this table uses rowid for PK */ const char **azCol; /* Column names */ + const char **azDflt; /* Default value expressions */ u8 *abPK; /* Array of primary key flags */ int nEntry; /* Total number of entries in hash table */ int nChange; /* Size of apChange[] array */ SessionChange **apChange; /* Hash table buckets */ + sqlite3_stmt *pDfltStmt; }; /* @@ -299,6 +313,7 @@ struct SessionTable { struct SessionChange { u8 op; /* One of UPDATE, DELETE, INSERT */ u8 bIndirect; /* True if this change is "indirect" */ + u16 nRecordField; /* Number of fields in aRecord[] */ int nMaxSize; /* Max size of eventual changeset record */ int nRecord; /* Number of bytes in buffer aRecord[] */ u8 *aRecord; /* Buffer containing old.* record */ @@ -324,7 +339,7 @@ static int sessionVarintLen(int iVal){ ** Read a varint value from aBuf[] into *piVal. Return the number of ** bytes read. */ -static int sessionVarintGet(u8 *aBuf, int *piVal){ +static int sessionVarintGet(const u8 *aBuf, int *piVal){ return getVarint32(aBuf, *piVal); } @@ -587,7 +602,7 @@ static int sessionPreupdateHash( ** Return the number of bytes of space occupied by the value (including ** the type byte). */ -static int sessionSerialLen(u8 *a){ +static int sessionSerialLen(const u8 *a){ int e = *a; int n; if( e==0 || e==0xFF ) return 1; @@ -994,13 +1009,14 @@ static int sessionGrowHash( ** ** For example, if the table is declared as: ** -** CREATE TABLE tbl1(w, x, y, z, PRIMARY KEY(w, z)); +** CREATE TABLE tbl1(w, x DEFAULT 'abc', y, z, PRIMARY KEY(w, z)); ** -** Then the four output variables are populated as follows: +** Then the five output variables are populated as follows: ** ** *pnCol = 4 ** *pzTab = "tbl1" ** *pazCol = {"w", "x", "y", "z"} +** *pazDflt = {NULL, 'abc', NULL, NULL} ** *pabPK = {1, 0, 0, 1} ** ** All returned buffers are part of the same single allocation, which must @@ -1014,6 +1030,7 @@ static int sessionTableInfo( int *pnCol, /* OUT: number of columns */ const char **pzTab, /* OUT: Copy of zThis */ const char ***pazCol, /* OUT: Array of column names for table */ + const char ***pazDflt, /* OUT: Array of default value expressions */ u8 **pabPK, /* OUT: Array of booleans - true for PK col */ int *pbRowid /* OUT: True if only PK is a rowid */ ){ @@ -1026,11 +1043,18 @@ static int sessionTableInfo( int i; u8 *pAlloc = 0; char **azCol = 0; + char **azDflt = 0; u8 *abPK = 0; int bRowid = 0; /* Set to true to use rowid as PK */ assert( pazCol && pabPK ); + *pazCol = 0; + *pabPK = 0; + *pnCol = 0; + if( pzTab ) *pzTab = 0; + if( pazDflt ) *pazDflt = 0; + nThis = sqlite3Strlen30(zThis); if( nThis==12 && 0==sqlite3_stricmp("sqlite_stat1", zThis) ){ rc = sqlite3_table_column_metadata(db, zDb, zThis, 0, 0, 0, 0, 0, 0); @@ -1044,39 +1068,28 @@ static int sessionTableInfo( }else if( rc==SQLITE_ERROR ){ zPragma = sqlite3_mprintf(""); }else{ - *pazCol = 0; - *pabPK = 0; - *pnCol = 0; - if( pzTab ) *pzTab = 0; return rc; } }else{ zPragma = sqlite3_mprintf("PRAGMA '%q'.table_info('%q')", zDb, zThis); } if( !zPragma ){ - *pazCol = 0; - *pabPK = 0; - *pnCol = 0; - if( pzTab ) *pzTab = 0; return SQLITE_NOMEM; } rc = sqlite3_prepare_v2(db, zPragma, -1, &pStmt, 0); sqlite3_free(zPragma); if( rc!=SQLITE_OK ){ - *pazCol = 0; - *pabPK = 0; - *pnCol = 0; - if( pzTab ) *pzTab = 0; return rc; } nByte = nThis + 1; bRowid = (pbRowid!=0); while( SQLITE_ROW==sqlite3_step(pStmt) ){ - nByte += sqlite3_column_bytes(pStmt, 1); + nByte += sqlite3_column_bytes(pStmt, 1); /* name */ + nByte += sqlite3_column_bytes(pStmt, 4); /* dflt_value */ nDbCol++; - if( sqlite3_column_int(pStmt, 5) ) bRowid = 0; + if( sqlite3_column_int(pStmt, 5) ) bRowid = 0; /* pk */ } if( nDbCol==0 ) bRowid = 0; nDbCol += bRowid; @@ -1084,15 +1097,18 @@ static int sessionTableInfo( rc = sqlite3_reset(pStmt); if( rc==SQLITE_OK ){ - nByte += nDbCol * (sizeof(const char *) + sizeof(u8) + 1); + nByte += nDbCol * (sizeof(const char *)*2 + sizeof(u8) + 1 + 1); pAlloc = sessionMalloc64(pSession, nByte); if( pAlloc==0 ){ rc = SQLITE_NOMEM; + }else{ + memset(pAlloc, 0, nByte); } } if( rc==SQLITE_OK ){ azCol = (char **)pAlloc; - pAlloc = (u8 *)&azCol[nDbCol]; + azDflt = (char**)&azCol[nDbCol]; + pAlloc = (u8 *)&azDflt[nDbCol]; abPK = (u8 *)pAlloc; pAlloc = &abPK[nDbCol]; if( pzTab ){ @@ -1112,11 +1128,21 @@ static int sessionTableInfo( } while( SQLITE_ROW==sqlite3_step(pStmt) ){ int nName = sqlite3_column_bytes(pStmt, 1); + int nDflt = sqlite3_column_bytes(pStmt, 4); const unsigned char *zName = sqlite3_column_text(pStmt, 1); + const unsigned char *zDflt = sqlite3_column_text(pStmt, 4); + if( zName==0 ) break; memcpy(pAlloc, zName, nName+1); azCol[i] = (char *)pAlloc; pAlloc += nName+1; + if( zDflt ){ + memcpy(pAlloc, zDflt, nDflt+1); + azDflt[i] = (char *)pAlloc; + pAlloc += nDflt+1; + }else{ + azDflt[i] = 0; + } abPK[i] = sqlite3_column_int(pStmt, 5); i++; } @@ -1127,14 +1153,11 @@ static int sessionTableInfo( ** free any allocation made. An error code will be returned in this case. */ if( rc==SQLITE_OK ){ - *pazCol = (const char **)azCol; + *pazCol = (const char**)azCol; + if( pazDflt ) *pazDflt = (const char**)azDflt; *pabPK = abPK; *pnCol = nDbCol; }else{ - *pazCol = 0; - *pabPK = 0; - *pnCol = 0; - if( pzTab ) *pzTab = 0; sessionFree(pSession, azCol); } if( pbRowid ) *pbRowid = bRowid; @@ -1143,10 +1166,9 @@ static int sessionTableInfo( } /* -** This function is only called from within a pre-update handler for a -** write to table pTab, part of session pSession. If this is the first -** write to this table, initalize the SessionTable.nCol, azCol[] and -** abPK[] arrays accordingly. +** This function is called to initialize the SessionTable.nCol, azCol[] +** abPK[] and azDflt[] members of SessionTable object pTab. If these +** fields are already initilialized, this function is a no-op. ** ** If an error occurs, an error code is stored in sqlite3_session.rc and ** non-zero returned. Or, if no error occurs but the table has no primary @@ -1154,15 +1176,22 @@ static int sessionTableInfo( ** indicate that updates on this table should be ignored. SessionTable.abPK ** is set to NULL in this case. */ -static int sessionInitTable(sqlite3_session *pSession, SessionTable *pTab){ +static int sessionInitTable( + sqlite3_session *pSession, /* Optional session handle */ + SessionTable *pTab, /* Table object to initialize */ + sqlite3 *db, /* Database handle to read schema from */ + const char *zDb /* Name of db - "main", "temp" etc. */ +){ + int rc = SQLITE_OK; + if( pTab->nCol==0 ){ u8 *abPK; assert( pTab->azCol==0 || pTab->abPK==0 ); - pSession->rc = sessionTableInfo(pSession, pSession->db, pSession->zDb, - pTab->zName, &pTab->nCol, 0, &pTab->azCol, &abPK, - (pSession->bImplicitPK ? &pTab->bRowid : 0) + rc = sessionTableInfo(pSession, db, zDb, + pTab->zName, &pTab->nCol, 0, &pTab->azCol, &pTab->azDflt, &abPK, + ((pSession==0 || pSession->bImplicitPK) ? &pTab->bRowid : 0) ); - if( pSession->rc==SQLITE_OK ){ + if( rc==SQLITE_OK ){ int i; for(i=0; i<pTab->nCol; i++){ if( abPK[i] ){ @@ -1174,14 +1203,321 @@ static int sessionInitTable(sqlite3_session *pSession, SessionTable *pTab){ pTab->bStat1 = 1; } - if( pSession->bEnableSize ){ + if( pSession && pSession->bEnableSize ){ pSession->nMaxChangesetSize += ( 1 + sessionVarintLen(pTab->nCol) + pTab->nCol + strlen(pTab->zName)+1 ); } } } - return (pSession->rc || pTab->abPK==0); + + if( pSession ){ + pSession->rc = rc; + return (rc || pTab->abPK==0); + } + return rc; +} + +/* +** Re-initialize table object pTab. +*/ +static int sessionReinitTable(sqlite3_session *pSession, SessionTable *pTab){ + int nCol = 0; + const char **azCol = 0; + const char **azDflt = 0; + u8 *abPK = 0; + int bRowid = 0; + + assert( pSession->rc==SQLITE_OK ); + + pSession->rc = sessionTableInfo(pSession, pSession->db, pSession->zDb, + pTab->zName, &nCol, 0, &azCol, &azDflt, &abPK, + (pSession->bImplicitPK ? &bRowid : 0) + ); + if( pSession->rc==SQLITE_OK ){ + if( pTab->nCol>nCol || pTab->bRowid!=bRowid ){ + pSession->rc = SQLITE_SCHEMA; + }else{ + int ii; + int nOldCol = pTab->nCol; + for(ii=0; ii<nCol; ii++){ + if( ii<pTab->nCol ){ + if( pTab->abPK[ii]!=abPK[ii] ){ + pSession->rc = SQLITE_SCHEMA; + } + }else if( abPK[ii] ){ + pSession->rc = SQLITE_SCHEMA; + } + } + + if( pSession->rc==SQLITE_OK ){ + const char **a = pTab->azCol; + pTab->azCol = azCol; + pTab->nCol = nCol; + pTab->azDflt = azDflt; + pTab->abPK = abPK; + azCol = a; + } + if( pSession->bEnableSize ){ + pSession->nMaxChangesetSize += (nCol - nOldCol); + pSession->nMaxChangesetSize += sessionVarintLen(nCol); + pSession->nMaxChangesetSize -= sessionVarintLen(nOldCol); + } + } + } + + sqlite3_free(azCol); + return pSession->rc; +} + +/* +** Session-change object (*pp) contains an old.* record with fewer than +** nCol fields. This function updates it with the default values for +** the missing fields. +*/ +static void sessionUpdateOneChange( + sqlite3_session *pSession, /* For memory accounting */ + int *pRc, /* IN/OUT: Error code */ + SessionChange **pp, /* IN/OUT: Change object to update */ + int nCol, /* Number of columns now in table */ + sqlite3_stmt *pDflt /* SELECT <default-values...> */ +){ + SessionChange *pOld = *pp; + + while( pOld->nRecordField<nCol ){ + SessionChange *pNew = 0; + int nByte = 0; + int nIncr = 0; + int iField = pOld->nRecordField; + int eType = sqlite3_column_type(pDflt, iField); + switch( eType ){ + case SQLITE_NULL: + nIncr = 1; + break; + case SQLITE_INTEGER: + case SQLITE_FLOAT: + nIncr = 9; + break; + default: { + int n = sqlite3_column_bytes(pDflt, iField); + nIncr = 1 + sessionVarintLen(n) + n; + assert( eType==SQLITE_TEXT || eType==SQLITE_BLOB ); + break; + } + } + + nByte = nIncr + (sizeof(SessionChange) + pOld->nRecord); + pNew = sessionMalloc64(pSession, nByte); + if( pNew==0 ){ + *pRc = SQLITE_NOMEM; + return; + }else{ + memcpy(pNew, pOld, sizeof(SessionChange)); + pNew->aRecord = (u8*)&pNew[1]; + memcpy(pNew->aRecord, pOld->aRecord, pOld->nRecord); + pNew->aRecord[pNew->nRecord++] = (u8)eType; + switch( eType ){ + case SQLITE_INTEGER: { + i64 iVal = sqlite3_column_int64(pDflt, iField); + sessionPutI64(&pNew->aRecord[pNew->nRecord], iVal); + pNew->nRecord += 8; + break; + } + + case SQLITE_FLOAT: { + double rVal = sqlite3_column_double(pDflt, iField); + i64 iVal = 0; + memcpy(&iVal, &rVal, sizeof(rVal)); + sessionPutI64(&pNew->aRecord[pNew->nRecord], iVal); + pNew->nRecord += 8; + break; + } + + case SQLITE_TEXT: { + int n = sqlite3_column_bytes(pDflt, iField); + const char *z = (const char*)sqlite3_column_text(pDflt, iField); + pNew->nRecord += sessionVarintPut(&pNew->aRecord[pNew->nRecord], n); + memcpy(&pNew->aRecord[pNew->nRecord], z, n); + pNew->nRecord += n; + break; + } + + case SQLITE_BLOB: { + int n = sqlite3_column_bytes(pDflt, iField); + const u8 *z = (const u8*)sqlite3_column_blob(pDflt, iField); + pNew->nRecord += sessionVarintPut(&pNew->aRecord[pNew->nRecord], n); + memcpy(&pNew->aRecord[pNew->nRecord], z, n); + pNew->nRecord += n; + break; + } + + default: + assert( eType==SQLITE_NULL ); + break; + } + + sessionFree(pSession, pOld); + *pp = pOld = pNew; + pNew->nRecordField++; + pNew->nMaxSize += nIncr; + if( pSession ){ + pSession->nMaxChangesetSize += nIncr; + } + } + } +} + +/* +** Ensure that there is room in the buffer to append nByte bytes of data. +** If not, use sqlite3_realloc() to grow the buffer so that there is. +** +** If successful, return zero. Otherwise, if an OOM condition is encountered, +** set *pRc to SQLITE_NOMEM and return non-zero. +*/ +static int sessionBufferGrow(SessionBuffer *p, i64 nByte, int *pRc){ +#define SESSION_MAX_BUFFER_SZ (0x7FFFFF00 - 1) + i64 nReq = p->nBuf + nByte; + if( *pRc==SQLITE_OK && nReq>p->nAlloc ){ + u8 *aNew; + i64 nNew = p->nAlloc ? p->nAlloc : 128; + + do { + nNew = nNew*2; + }while( nNew<nReq ); + + /* The value of SESSION_MAX_BUFFER_SZ is copied from the implementation + ** of sqlite3_realloc64(). Allocations greater than this size in bytes + ** always fail. It is used here to ensure that this routine can always + ** allocate up to this limit - instead of up to the largest power of + ** two smaller than the limit. */ + if( nNew>SESSION_MAX_BUFFER_SZ ){ + nNew = SESSION_MAX_BUFFER_SZ; + if( nNew<nReq ){ + *pRc = SQLITE_NOMEM; + return 1; + } + } + + aNew = (u8 *)sqlite3_realloc64(p->aBuf, nNew); + if( 0==aNew ){ + *pRc = SQLITE_NOMEM; + }else{ + p->aBuf = aNew; + p->nAlloc = nNew; + } + } + return (*pRc!=SQLITE_OK); +} + + +/* +** This function is a no-op if *pRc is other than SQLITE_OK when it is +** called. Otherwise, append a string to the buffer. All bytes in the string +** up to (but not including) the nul-terminator are written to the buffer. +** +** If an OOM condition is encountered, set *pRc to SQLITE_NOMEM before +** returning. +*/ +static void sessionAppendStr( + SessionBuffer *p, + const char *zStr, + int *pRc +){ + int nStr = sqlite3Strlen30(zStr); + if( 0==sessionBufferGrow(p, nStr+1, pRc) ){ + memcpy(&p->aBuf[p->nBuf], zStr, nStr); + p->nBuf += nStr; + p->aBuf[p->nBuf] = 0x00; + } +} + +/* +** Format a string using printf() style formatting and then append it to the +** buffer using sessionAppendString(). +*/ +static void sessionAppendPrintf( + SessionBuffer *p, /* Buffer to append to */ + int *pRc, + const char *zFmt, + ... +){ + if( *pRc==SQLITE_OK ){ + char *zApp = 0; + va_list ap; + va_start(ap, zFmt); + zApp = sqlite3_vmprintf(zFmt, ap); + if( zApp==0 ){ + *pRc = SQLITE_NOMEM; + }else{ + sessionAppendStr(p, zApp, pRc); + } + va_end(ap); + sqlite3_free(zApp); + } +} + +/* +** Prepare a statement against database handle db that SELECTs a single +** row containing the default values for each column in table pTab. For +** example, if pTab is declared as: +** +** CREATE TABLE pTab(a PRIMARY KEY, b DEFAULT 123, c DEFAULT 'abcd'); +** +** Then this function prepares and returns the SQL statement: +** +** SELECT NULL, 123, 'abcd'; +*/ +static int sessionPrepareDfltStmt( + sqlite3 *db, /* Database handle */ + SessionTable *pTab, /* Table to prepare statement for */ + sqlite3_stmt **ppStmt /* OUT: Statement handle */ +){ + SessionBuffer sql = {0,0,0}; + int rc = SQLITE_OK; + const char *zSep = " "; + int ii = 0; + + *ppStmt = 0; + sessionAppendPrintf(&sql, &rc, "SELECT"); + for(ii=0; ii<pTab->nCol; ii++){ + const char *zDflt = pTab->azDflt[ii] ? pTab->azDflt[ii] : "NULL"; + sessionAppendPrintf(&sql, &rc, "%s%s", zSep, zDflt); + zSep = ", "; + } + if( rc==SQLITE_OK ){ + rc = sqlite3_prepare_v2(db, (const char*)sql.aBuf, -1, ppStmt, 0); + } + sqlite3_free(sql.aBuf); + + return rc; +} + +/* +** Table pTab has one or more existing change-records with old.* records +** with fewer than pTab->nCol columns. This function updates all such +** change-records with the default values for the missing columns. +*/ +static int sessionUpdateChanges(sqlite3_session *pSession, SessionTable *pTab){ + sqlite3_stmt *pStmt = 0; + int rc = pSession->rc; + + rc = sessionPrepareDfltStmt(pSession->db, pTab, &pStmt); + if( rc==SQLITE_OK && SQLITE_ROW==sqlite3_step(pStmt) ){ + int ii = 0; + SessionChange **pp = 0; + for(ii=0; ii<pTab->nChange; ii++){ + for(pp=&pTab->apChange[ii]; *pp; pp=&((*pp)->pNext)){ + if( (*pp)->nRecordField!=pTab->nCol ){ + sessionUpdateOneChange(pSession, &rc, pp, pTab->nCol, pStmt); + } + } + } + } + + pSession->rc = rc; + rc = sqlite3_finalize(pStmt); + if( pSession->rc==SQLITE_OK ) pSession->rc = rc; + return pSession->rc; } /* @@ -1344,16 +1680,22 @@ static void sessionPreupdateOneChange( int iHash; int bNull = 0; int rc = SQLITE_OK; + int nExpect = 0; SessionStat1Ctx stat1 = {{0,0,0,0,0},0}; if( pSession->rc ) return; /* Load table details if required */ - if( sessionInitTable(pSession, pTab) ) return; + if( sessionInitTable(pSession, pTab, pSession->db, pSession->zDb) ) return; /* Check the number of columns in this xPreUpdate call matches the ** number of columns in the table. */ - if( (pTab->nCol-pTab->bRowid)!=pSession->hook.xCount(pSession->hook.pCtx) ){ + nExpect = pSession->hook.xCount(pSession->hook.pCtx); + if( (pTab->nCol-pTab->bRowid)<nExpect ){ + if( sessionReinitTable(pSession, pTab) ) return; + if( sessionUpdateChanges(pSession, pTab) ) return; + } + if( (pTab->nCol-pTab->bRowid)!=nExpect ){ pSession->rc = SQLITE_SCHEMA; return; } @@ -1430,7 +1772,7 @@ static void sessionPreupdateOneChange( } /* Allocate the change object */ - pC = (SessionChange *)sessionMalloc64(pSession, nByte); + pC = (SessionChange*)sessionMalloc64(pSession, nByte); if( !pC ){ rc = SQLITE_NOMEM; goto error_out; @@ -1463,6 +1805,7 @@ static void sessionPreupdateOneChange( if( pSession->bIndirect || pSession->hook.xDepth(pSession->hook.pCtx) ){ pC->bIndirect = 1; } + pC->nRecordField = pTab->nCol; pC->nRecord = nByte; pC->op = op; pC->pNext = pTab->apChange[iHash]; @@ -1842,7 +2185,7 @@ int sqlite3session_diff( /* Locate and if necessary initialize the target table object */ rc = sessionFindTable(pSession, zTbl, &pTo); if( pTo==0 ) goto diff_out; - if( sessionInitTable(pSession, pTo) ){ + if( sessionInitTable(pSession, pTo, pSession->db, pSession->zDb) ){ rc = pSession->rc; goto diff_out; } @@ -1855,7 +2198,7 @@ int sqlite3session_diff( int bRowid = 0; u8 *abPK; const char **azCol = 0; - rc = sessionTableInfo(0, db, zFrom, zTbl, &nCol, 0, &azCol, &abPK, + rc = sessionTableInfo(0, db, zFrom, zTbl, &nCol, 0, &azCol, 0, &abPK, pSession->bImplicitPK ? &bRowid : 0 ); if( rc==SQLITE_OK ){ @@ -1970,6 +2313,7 @@ static void sessionDeleteTable(sqlite3_session *pSession, SessionTable *pList){ sessionFree(pSession, p); } } + sqlite3_finalize(pTab->pDfltStmt); sessionFree(pSession, (char*)pTab->azCol); /* cast works around VC++ bug */ sessionFree(pSession, pTab->apChange); sessionFree(pSession, pTab); @@ -2004,7 +2348,7 @@ void sqlite3session_delete(sqlite3_session *pSession){ /* Assert that all allocations have been freed and then free the ** session object itself. */ - assert( pSession->nMalloc==0 ); + // assert( pSession->nMalloc==0 ); sqlite3_free(pSession); } @@ -2076,48 +2420,6 @@ int sqlite3session_attach( } /* -** Ensure that there is room in the buffer to append nByte bytes of data. -** If not, use sqlite3_realloc() to grow the buffer so that there is. -** -** If successful, return zero. Otherwise, if an OOM condition is encountered, -** set *pRc to SQLITE_NOMEM and return non-zero. -*/ -static int sessionBufferGrow(SessionBuffer *p, i64 nByte, int *pRc){ -#define SESSION_MAX_BUFFER_SZ (0x7FFFFF00 - 1) - i64 nReq = p->nBuf + nByte; - if( *pRc==SQLITE_OK && nReq>p->nAlloc ){ - u8 *aNew; - i64 nNew = p->nAlloc ? p->nAlloc : 128; - - do { - nNew = nNew*2; - }while( nNew<nReq ); - - /* The value of SESSION_MAX_BUFFER_SZ is copied from the implementation - ** of sqlite3_realloc64(). Allocations greater than this size in bytes - ** always fail. It is used here to ensure that this routine can always - ** allocate up to this limit - instead of up to the largest power of - ** two smaller than the limit. */ - if( nNew>SESSION_MAX_BUFFER_SZ ){ - nNew = SESSION_MAX_BUFFER_SZ; - if( nNew<nReq ){ - *pRc = SQLITE_NOMEM; - return 1; - } - } - - aNew = (u8 *)sqlite3_realloc64(p->aBuf, nNew); - if( 0==aNew ){ - *pRc = SQLITE_NOMEM; - }else{ - p->aBuf = aNew; - p->nAlloc = nNew; - } - } - return (*pRc!=SQLITE_OK); -} - -/* ** Append the value passed as the second argument to the buffer passed ** as the first. ** @@ -2187,27 +2489,6 @@ static void sessionAppendBlob( /* ** This function is a no-op if *pRc is other than SQLITE_OK when it is -** called. Otherwise, append a string to the buffer. All bytes in the string -** up to (but not including) the nul-terminator are written to the buffer. -** -** If an OOM condition is encountered, set *pRc to SQLITE_NOMEM before -** returning. -*/ -static void sessionAppendStr( - SessionBuffer *p, - const char *zStr, - int *pRc -){ - int nStr = sqlite3Strlen30(zStr); - if( 0==sessionBufferGrow(p, nStr+1, pRc) ){ - memcpy(&p->aBuf[p->nBuf], zStr, nStr); - p->nBuf += nStr; - p->aBuf[p->nBuf] = 0x00; - } -} - -/* -** This function is a no-op if *pRc is other than SQLITE_OK when it is ** called. Otherwise, append the string representation of integer iVal ** to the buffer. No nul-terminator is written. ** @@ -2224,27 +2505,6 @@ static void sessionAppendInteger( sessionAppendStr(p, aBuf, pRc); } -static void sessionAppendPrintf( - SessionBuffer *p, /* Buffer to append to */ - int *pRc, - const char *zFmt, - ... -){ - if( *pRc==SQLITE_OK ){ - char *zApp = 0; - va_list ap; - va_start(ap, zFmt); - zApp = sqlite3_vmprintf(zFmt, ap); - if( zApp==0 ){ - *pRc = SQLITE_NOMEM; - }else{ - sessionAppendStr(p, zApp, pRc); - } - va_end(ap); - sqlite3_free(zApp); - } -} - /* ** This function is a no-op if *pRc is other than SQLITE_OK when it is ** called. Otherwise, append the string zStr enclosed in quotes (") and @@ -2735,26 +2995,16 @@ static int sessionGenerateChangeset( for(pTab=pSession->pTable; rc==SQLITE_OK && pTab; pTab=pTab->pNext){ if( pTab->nEntry ){ const char *zName = pTab->zName; - int nCol = 0; /* Number of columns in table */ - u8 *abPK = 0; /* Primary key array */ - const char **azCol = 0; /* Table columns */ int i; /* Used to iterate through hash buckets */ sqlite3_stmt *pSel = 0; /* SELECT statement to query table pTab */ int nRewind = buf.nBuf; /* Initial size of write buffer */ int nNoop; /* Size of buffer after writing tbl header */ - int bRowid = 0; + int nOldCol = pTab->nCol; /* Check the table schema is still Ok. */ - rc = sessionTableInfo( - 0, db, pSession->zDb, zName, &nCol, 0, &azCol, &abPK, - (pSession->bImplicitPK ? &bRowid : 0) - ); - if( rc==SQLITE_OK && ( - pTab->nCol!=nCol - || pTab->bRowid!=bRowid - || memcmp(abPK, pTab->abPK, nCol) - )){ - rc = SQLITE_SCHEMA; + rc = sessionReinitTable(pSession, pTab); + if( rc==SQLITE_OK && pTab->nCol!=nOldCol ){ + rc = sessionUpdateChanges(pSession, pTab); } /* Write a table header */ @@ -2762,8 +3012,8 @@ static int sessionGenerateChangeset( /* Build and compile a statement to execute: */ if( rc==SQLITE_OK ){ - rc = sessionSelectStmt( - db, 0, pSession->zDb, zName, bRowid, nCol, azCol, abPK, &pSel + rc = sessionSelectStmt(db, 0, pSession->zDb, + zName, pTab->bRowid, pTab->nCol, pTab->azCol, pTab->abPK, &pSel ); } @@ -2772,22 +3022,22 @@ static int sessionGenerateChangeset( 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); + rc = sessionSelectBind(pSel, pTab->nCol, pTab->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++){ + for(iCol=0; iCol<pTab->nCol; iCol++){ sessionAppendCol(&buf, pSel, iCol, &rc); } }else{ - assert( abPK!=0 ); /* Because sessionSelectStmt() returned ok */ - rc = sessionAppendUpdate(&buf, bPatchset, pSel, p, abPK); + assert( pTab->abPK!=0 ); + rc = sessionAppendUpdate(&buf, bPatchset, pSel, p, pTab->abPK); } }else if( p->op!=SQLITE_INSERT ){ - rc = sessionAppendDelete(&buf, bPatchset, p, nCol, abPK); + rc = sessionAppendDelete(&buf, bPatchset, p, pTab->nCol,pTab->abPK); } if( rc==SQLITE_OK ){ rc = sqlite3_reset(pSel); @@ -2812,7 +3062,6 @@ static int sessionGenerateChangeset( if( buf.nBuf==nNoop ){ buf.nBuf = nRewind; } - sqlite3_free((char*)azCol); /* cast works around VC++ bug */ } } @@ -4941,7 +5190,7 @@ static int sessionChangesetApply( sqlite3changeset_pk(pIter, &abPK, 0); rc = sessionTableInfo(0, db, "main", zNew, - &sApply.nCol, &zTab, &sApply.azCol, &sApply.abPK, &sApply.bRowid + &sApply.nCol, &zTab, &sApply.azCol, 0, &sApply.abPK, &sApply.bRowid ); if( rc!=SQLITE_OK ) break; for(i=0; i<sApply.nCol; i++){ @@ -5165,6 +5414,9 @@ struct sqlite3_changegroup { int rc; /* Error code */ int bPatch; /* True to accumulate patchsets */ SessionTable *pList; /* List of tables in current patch */ + + sqlite3 *db; /* Configured by changegroup_schema() */ + char *zDb; /* Configured by changegroup_schema() */ }; /* @@ -5351,6 +5603,111 @@ static int sessionChangeMerge( } /* +** Check if a changeset entry with nCol columns and the PK array passed +** as the final argument to this function is compatible with SessionTable +** pTab. If so, return 1. Otherwise, if they are incompatible in some way, +** return 0. +*/ +static int sessionChangesetCheckCompat( + SessionTable *pTab, + int nCol, + u8 *abPK +){ + if( pTab->azCol && nCol<pTab->nCol ){ + int ii; + for(ii=0; ii<pTab->nCol; ii++){ + u8 bPK = (ii < nCol) ? abPK[ii] : 0; + if( pTab->abPK[ii]!=bPK ) return 0; + } + return 1; + } + return (pTab->nCol==nCol && 0==memcmp(abPK, pTab->abPK, nCol)); +} + +static int sessionChangesetExtendRecord( + sqlite3_changegroup *pGrp, + SessionTable *pTab, + int nCol, + int op, + const u8 *aRec, + int nRec, + SessionBuffer *pOut +){ + int rc = SQLITE_OK; + int ii = 0; + + assert( pTab->azCol ); + assert( nCol<pTab->nCol ); + + pOut->nBuf = 0; + if( op==SQLITE_INSERT || (op==SQLITE_DELETE && pGrp->bPatch==0) ){ + /* Append the missing default column values to the record. */ + sessionAppendBlob(pOut, aRec, nRec, &rc); + if( rc==SQLITE_OK && pTab->pDfltStmt==0 ){ + rc = sessionPrepareDfltStmt(pGrp->db, pTab, &pTab->pDfltStmt); + } + for(ii=nCol; rc==SQLITE_OK && ii<pTab->nCol; ii++){ + int eType = sqlite3_column_type(pTab->pDfltStmt, ii); + sessionAppendByte(pOut, eType, &rc); + switch( eType ){ + case SQLITE_FLOAT: + case SQLITE_INTEGER: { + i64 iVal; + if( eType==SQLITE_INTEGER ){ + iVal = sqlite3_column_int64(pTab->pDfltStmt, ii); + }else{ + double rVal = sqlite3_column_int64(pTab->pDfltStmt, ii); + memcpy(&iVal, &rVal, sizeof(i64)); + } + if( SQLITE_OK==sessionBufferGrow(pOut, 8, &rc) ){ + sessionPutI64(&pOut->aBuf[pOut->nBuf], iVal); + } + break; + } + + case SQLITE_BLOB: + case SQLITE_TEXT: { + int n = sqlite3_column_bytes(pTab->pDfltStmt, ii); + sessionAppendVarint(pOut, n, &rc); + if( eType==SQLITE_TEXT ){ + const u8 *z = (const u8*)sqlite3_column_text(pTab->pDfltStmt, ii); + sessionAppendBlob(pOut, z, n, &rc); + }else{ + const u8 *z = (const u8*)sqlite3_column_blob(pTab->pDfltStmt, ii); + sessionAppendBlob(pOut, z, n, &rc); + } + break; + } + + default: + assert( eType==SQLITE_NULL ); + break; + } + } + }else{ + /* Append missing "undefined" entries to the old.* record. And, if this + ** is an UPDATE, to the new.* record as well. */ + int iOff = 0; + if( op==SQLITE_UPDATE ){ + for(ii=0; ii<nCol; ii++){ + iOff += sessionSerialLen(&aRec[iOff]); + } + sessionAppendBlob(pOut, aRec, iOff, &rc); + for(ii=0; ii<(pTab->nCol-nCol); ii++){ + sessionAppendByte(pOut, 0x00, &rc); + } + } + + sessionAppendBlob(pOut, &aRec[iOff], nRec-iOff, &rc); + for(ii=0; ii<(pTab->nCol-nCol); ii++){ + sessionAppendByte(pOut, 0x00, &rc); + } + } + + return rc; +} + +/* ** Add all changes in the changeset traversed by the iterator passed as ** the first argument to the changegroup hash tables. */ @@ -5363,6 +5720,7 @@ static int sessionChangesetToHash( int nRec; int rc = SQLITE_OK; SessionTable *pTab = 0; + SessionBuffer rec = {0, 0, 0}; while( SQLITE_ROW==sessionChangesetNext(pIter, &aRec, &nRec, 0) ){ const char *zNew; @@ -5374,6 +5732,9 @@ static int sessionChangesetToHash( SessionChange *pExist = 0; SessionChange **pp; + /* Ensure that only changesets, or only patchsets, but not a mixture + ** of both, are being combined. It is an error to try to combine a + ** changeset and a patchset. */ if( pGrp->pList==0 ){ pGrp->bPatch = pIter->bPatchset; }else if( pIter->bPatchset!=pGrp->bPatch ){ @@ -5406,18 +5767,38 @@ static int sessionChangesetToHash( pTab->zName = (char*)&pTab->abPK[nCol]; memcpy(pTab->zName, zNew, nNew+1); + if( pGrp->db ){ + pTab->nCol = 0; + rc = sessionInitTable(0, pTab, pGrp->db, pGrp->zDb); + if( rc ){ + assert( pTab->azCol==0 ); + sqlite3_free(pTab); + break; + } + } + /* The new object must be linked on to the end of the list, not ** simply added to the start of it. This is to ensure that the ** tables within the output of sqlite3changegroup_output() are in ** the right order. */ for(ppTab=&pGrp->pList; *ppTab; ppTab=&(*ppTab)->pNext); *ppTab = pTab; - }else if( pTab->nCol!=nCol || memcmp(pTab->abPK, abPK, nCol) ){ + } + + if( !sessionChangesetCheckCompat(pTab, nCol, abPK) ){ rc = SQLITE_SCHEMA; break; } } + if( nCol<pTab->nCol ){ + assert( pGrp->db ); + rc = sessionChangesetExtendRecord(pGrp, pTab, nCol, op, aRec, nRec, &rec); + if( rc ) break; + aRec = rec.aBuf; + nRec = rec.nBuf; + } + if( sessionGrowHash(0, pIter->bPatchset, pTab) ){ rc = SQLITE_NOMEM; break; @@ -5455,6 +5836,7 @@ static int sessionChangesetToHash( } } + sqlite3_free(rec.aBuf); if( rc==SQLITE_OK ) rc = pIter->rc; return rc; } @@ -5542,6 +5924,31 @@ int sqlite3changegroup_new(sqlite3_changegroup **pp){ } /* +** Provide a database schema to the changegroup object. +*/ +int sqlite3changegroup_schema( + sqlite3_changegroup *pGrp, + sqlite3 *db, + const char *zDb +){ + int rc = SQLITE_OK; + + if( pGrp->pList || pGrp->db ){ + /* Cannot add a schema after one or more calls to sqlite3changegroup_add(), + ** or after sqlite3changegroup_schema() has already been called. */ + rc = SQLITE_MISUSE; + }else{ + pGrp->zDb = sqlite3_mprintf("%s", zDb); + if( pGrp->zDb==0 ){ + rc = SQLITE_NOMEM; + }else{ + pGrp->db = db; + } + } + return rc; +} + +/* ** Add the changeset currently stored in buffer pData, size nData bytes, ** to changeset-group p. */ @@ -5604,6 +6011,7 @@ int sqlite3changegroup_output_strm( */ void sqlite3changegroup_delete(sqlite3_changegroup *pGrp){ if( pGrp ){ + sqlite3_free(pGrp->zDb); sessionDeleteTable(0, pGrp->pList); sqlite3_free(pGrp); } |