/* Merge one block of an on-disk doclist into a DocListMerge. */
static void mergeBlock(DocListMerge *m, DocList *pBlock){
DocListReader blockReader;
assert( pBlock->iType >= DL_POSITIONS );
readerInit(&blockReader, pBlock);
while( !readerAtEnd(&blockReader) ){
sqlite_int64 iDocid = readDocid(&blockReader);
if( m->in.pDoclist!=NULL ){
while( 1 ){
if( readerAtEnd(&m->in) ) return; /* nothing more to merge */
if( peekDocid(&m->in)>=iDocid ) break;
skipDocument(&m->in);
}
if( peekDocid(&m->in)>iDocid ){ /* [pIn] has no match with iDocid */
skipPositionList(&blockReader); /* skip this docid in the block */
continue;
}
readDocid(&m->in);
}
/* We have a document match. */
if( m->in.pDoclist==NULL || m->in.pDoclist->iType < DL_POSITIONS ){
/* We don't need to do a poslist merge. */
docListAddDocid(m->pOut, iDocid);
if( m->pOut->iType >= DL_POSITIONS ){
/* Copy all positions to the output doclist. */
while( 1 ){
int pos = readPosition(&blockReader);
if( pos==-1 ) break;
docListAddPos(m->pOut, pos);
}
docListAddEndPos(m->pOut);
} else skipPositionList(&blockReader);
continue;
}
mergePosList(m, iDocid, &blockReader);
}
}
static void mergeBlock(DocListMerge *m, DocList *pBlock){
DocListReader blockReader;
assert( pBlock->iType >= DL_POSITIONS );
readerInit(&blockReader, pBlock);
while( !readerAtEnd(&blockReader) ){
sqlite_int64 iDocid = readDocid(&blockReader);
if( m->in.pDoclist!=NULL ){
while( 1 ){
if( readerAtEnd(&m->in) ) return;
if( peekDocid(&m->in)>=iDocid ) break;
skipDocument(&m->in);
}
if( peekDocid(&m->in)>iDocid ){
skipPositionList(&blockReader);
continue;
}
readDocid(&m->in);
}
if( m->in.pDoclist==NULL || m->in.pDoclist->iType < DL_POSITIONS ){
docListAddDocid(m->pOut, iDocid);
if( m->pOut->iType >= DL_POSITIONS ){
while( 1 ){
int pos = readPosition(&blockReader);
if( pos==-1 ) break;
docListAddPos(m->pOut, pos);
}
docListAddEndPos(m->pOut);
} else skipPositionList(&blockReader);
continue;
}
mergePosList(m, iDocid, &blockReader);
}
}
static int fulltextNext(sqlite3_vtab_cursor *pCursor){
fulltext_cursor *c = (fulltext_cursor *) pCursor;
sqlite_int64 iDocid;
int rc;
switch( c->iCursorType ){
case QUERY_GENERIC:
/* TODO(shess) Handle SQLITE_SCHEMA AND SQLITE_BUSY. */
rc = sqlite3_step(c->pStmt);
switch( rc ){
case SQLITE_ROW:
c->eof = 0;
return SQLITE_OK;
case SQLITE_DONE:
c->eof = 1;
return SQLITE_OK;
default:
c->eof = 1;
return rc;
}
case QUERY_FULLTEXT:
rc = sqlite3_reset(c->pStmt);
if( rc!=SQLITE_OK ) return rc;
if( readerAtEnd(&c->result)){
c->eof = 1;
return SQLITE_OK;
}
iDocid = readDocid(&c->result);
rc = sqlite3_bind_int64(c->pStmt, 1, iDocid);
if( rc!=SQLITE_OK ) return rc;
/* TODO(shess) Handle SQLITE_SCHEMA AND SQLITE_BUSY. */
rc = sqlite3_step(c->pStmt);
if( rc==SQLITE_ROW ){ /* the case we expect */
c->eof = 0;
return SQLITE_OK;
}
/* an error occurred; abort */
return rc==SQLITE_DONE ? SQLITE_ERROR : rc;
default:
assert( 0 );
return SQLITE_ERROR; /* not reached */
}
}
static int fulltextNext(sqlite3_vtab_cursor *pCursor){
fulltext_cursor *c = (fulltext_cursor *) pCursor;
sqlite_int64 iDocid;
int rc;
switch( c->iCursorType ){
case QUERY_GENERIC:
rc = sqlite3_step(c->pStmt);
switch( rc ){
case SQLITE_ROW:
c->eof = 0;
return SQLITE_OK;
case SQLITE_DONE:
c->eof = 1;
return SQLITE_OK;
default:
c->eof = 1;
return rc;
}
case QUERY_FULLTEXT:
rc = sqlite3_reset(c->pStmt);
if( rc!=SQLITE_OK ) return rc;
if( readerAtEnd(&c->result)){
c->eof = 1;
return SQLITE_OK;
}
iDocid = readDocid(&c->result);
rc = sqlite3_bind_int64(c->pStmt, 1, iDocid);
if( rc!=SQLITE_OK ) return rc;
rc = sqlite3_step(c->pStmt);
if( rc==SQLITE_ROW ){
c->eof = 0;
return SQLITE_OK;
}
return rc==SQLITE_DONE ? SQLITE_ERROR : rc;
default:
assert( 0 );
return SQLITE_ERROR;
}
}
static sqlite_int64 firstDocid(DocList *d){
DocListReader r;
readerInit(&r, d);
return readDocid(&r);
}
/* Skip over a docid, including its position list if the doclist has
* positions. */
static void skipDocument(DocListReader *pReader){
readDocid(pReader);
if( pReader->pDoclist->iType >= DL_POSITIONS ){
skipPositionList(pReader);
}
}
