void UDBIndex_finishOpening(UDBIndex *self)
{
JFile_begin(self->file);
UDBIndex_setPos_forPid_(self, 0, 0);
UDBIndex_preCommit(self);
UDBIndex_findHoles(self);
}
void UDB_append_withPid_(UDB *self, Datum d, PID_TYPE pid)
{
UDBRecord *record = UDBRecords_newRecord(self->records);
UDBRecord_pid_(record, pid);
UDBRecord_saveWithDatum_(record, d);
UDBIndex_setPos_forPid_(self->index, UDBRecord_pos(record), pid);
}
void UDB_removeAt_(UDB *self, PID_TYPE pid)
{
if (UDB_isInTransaction(self))
{
UDBRecord *record = UDB_recordAtPid_(self, pid);
if (!record)
{
printf("UDB error: missing record with pid %" PID_FORMAT " for remove\n", pid);
record = UDB_recordAtPid_(self, pid);
return;
}
UDBRecords_removeRecord_(self->records, record);
UDBIndex_setPos_forPid_(self->index, 0, pid);
}
}
int UDB_compactStepFor_(UDB *self, double maxSeconds)
{
UDBRecord *firstEmptyRecord = UDBRecords_firstEmptyRecord(self->records);
if (!firstEmptyRecord)
{
return 0;
}
if (!UDBRecord_isEmpty(firstEmptyRecord))
{
printf("firstEmptyRecord not empty!\n");
firstEmptyRecord = UDBRecords_firstEmptyRecord(self->records);
UDBRecord_isEmpty(firstEmptyRecord);
exit(1);
}
#ifdef DEBUG
printf("empty record pid: %i pos: %i size: %i isEmpty: %i\n",
UDBRecord_pid(firstEmptyRecord),
UDBRecord_pos(firstEmptyRecord),
UDBRecord_totalSize(firstEmptyRecord),
UDBRecord_isEmpty(firstEmptyRecord));
#endif
if (firstEmptyRecord)
{
UDBRecord *record = UDBRecords_recordAfter_(self->records, firstEmptyRecord);
if (!record)
{
// reached end of file
PID_TYPE size = UDBRecord_pos(firstEmptyRecord);
UDBRecords_truncate_(self->records, size);
return 0;
}
#ifdef DEBUG
printf("next record pid: %i pos: %i size: %i isEmpty: %i\n\n",
UDBRecord_pid(record),
UDBRecord_pos(record),
UDBRecord_totalSize(record),
UDBRecord_isEmpty(record));
#endif
UDB_beginTransaction(self);
if (UDBRecord_isEmpty(record))
{
// coalese this empty record into the first empty record
PID_TYPE newSize = UDBRecord_totalSize(firstEmptyRecord)
- sizeof(UDBRecordHeader) + UDBRecord_totalSize(record);
UDBRecord_size_(firstEmptyRecord, newSize);
UDBRecord_saveHeader(firstEmptyRecord);
#ifdef DEBUG
printf("merge\n");
#endif
UDBIndex_setPos_forPid_(self->index, 0, UDBRecord_pid(record));
}
else
{
// swap places with the first empty record
PID_TYPE oldEmptyPos = UDBRecord_pos(firstEmptyRecord);
PID_TYPE newEmptyPos = oldEmptyPos + UDBRecord_totalSize(record);
UDBRecords_firstEmptyRecordPos_(self->records, newEmptyPos);
UDBRecord_moveToPos_(record, UDBRecord_pos(firstEmptyRecord));
UDBRecord_setPos_(firstEmptyRecord, newEmptyPos);
UDBRecord_saveHeader(firstEmptyRecord);
#ifdef DEBUG
printf("move\n");
#endif
UDBIndex_setPos_forPid_(self->index, newEmptyPos, UDBRecord_pid(firstEmptyRecord));
UDBIndex_setPos_forPid_(self->index, oldEmptyPos, UDBRecord_pid(record));
}
UDB_commitTransaction(self);
return 1;
}
return 0;
}