** 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.
*/
struct SessionTable {
SessionTable *pNext;
int nEntry; /* Total number of entries in hash table */
int nChange; /* Size of apChange[] array */
SessionChange **apChange; /* Hash table buckets */
+
+ sqlite3_stmt *pDfltStmt;
};
/*
** 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);
}
** 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;
** 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,
+ SessionTable *pTab,
+ sqlite3 *db,
+ const char *zDb
+){
+ 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,
+ rc = sessionTableInfo(pSession, db, zDb,
pTab->zName, &pTab->nCol, 0, &pTab->azCol, &pTab->azDflt, &abPK,
- (pSession->bImplicitPK ? &pTab->bRowid : 0)
+ ((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] ){
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;
}
static int sessionReinitTable(sqlite3_session *pSession, SessionTable *pTab){
}
}
-static int sessionUpdateChanges(sqlite3_session *pSession, SessionTable *pTab){
- sqlite3 *db = pSession->db;
+/*
+** 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};
- sqlite3_stmt *pStmt = 0;
+ int rc = SQLITE_OK;
const char *zSep = " ";
int ii = 0;
- int rc = pSession->rc;
+ *ppStmt = 0;
sessionAppendPrintf(&sql, &rc, "SELECT");
for(ii=0; ii<pTab->nCol; ii++){
const char *zDflt = pTab->azDflt[ii] ? pTab->azDflt[ii] : "NULL";
zSep = ", ";
}
if( rc==SQLITE_OK ){
- rc = sqlite3_prepare_v2(db, (const char*)sql.aBuf, -1, &pStmt, 0);
+ rc = sqlite3_prepare_v2(db, (const char*)sql.aBuf, -1, ppStmt, 0);
}
+ sqlite3_free(sql.aBuf);
+
+ return rc;
+}
+
+static int sessionUpdateChanges(sqlite3_session *pSession, SessionTable *pTab){
+ sqlite3 *db = pSession->db;
+ sqlite3_stmt *pStmt = 0;
+ int ii = 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)){
}
}
- sqlite3_free(sql.aBuf);
pSession->rc = rc;
rc = sqlite3_finalize(pStmt);
if( pSession->rc==SQLITE_OK ) pSession->rc = rc;
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. */
/* 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;
}
int rc; /* Error code */
int bPatch; /* True to accumulate patchsets */
SessionTable *pList; /* List of tables in current patch */
+
+ sqlite3 *db; /* Configured by changegroup_schema() */
+ const char *zDb; /* Configured by changegroup_schema() */
};
/*
return rc;
}
+/*
+** 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( 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.
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;
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 ){
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);
+ }
+
/* 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;
}
}
+ sqlite3_free(rec.aBuf);
if( rc==SQLITE_OK ) rc = pIter->rc;
return rc;
}
return rc;
}
+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.
projects / thirdparty / sqlite.git / commitdiff
