func TestSimpleJSONDB_InitializesDataFile(t *testing.T) {
firstDataBlock := make([]byte, 10)
blocksBitMapBlock := make([]byte, dbio.DATABLOCK_SIZE)
bTreeRootBlock := make([]byte, 2)
fakeDataFile := utils.NewFakeDataFileWithBlocks([][]byte{
firstDataBlock,
blocksBitMapBlock,
nil,
nil,
bTreeRootBlock,
})
jsondb.NewWithDataFile(fakeDataFile)
if !utils.SlicesEqual(firstDataBlock[0:2], []byte{0x00, 0x03}) {
t.Error("Did not set the next available data block pointer to 3")
}
if !utils.SlicesEqual(firstDataBlock[2:4], []byte{0x00, 0x03}) {
t.Error("Did not set the first record block pointer to 3")
}
blocksBitMap := dbio.NewBitMapFromBytes(blocksBitMapBlock)
for i := 0; i < 4; i++ {
val, err := blocksBitMap.Get(i)
if err != nil {
t.Fatal(err)
}
if !val {
t.Errorf("Expected block %d to be flagged as used", i)
}
}
}
func (dbm *dataBlocksMap) tupleForBlockID(dataBlockID uint16) (dbio.BitMap, int) {
blockOffset := dataBlockID / dbio.DATABLOCK_SIZE
flagOffset := dataBlockID % dbio.DATABLOCK_SIZE
block, err := dbm.dataBuffer.FetchBlock(DATA_BLOCK_MAP_FIRST_BLOCK + blockOffset)
if err != nil {
panic(err)
}
return dbio.NewBitMapFromBytes(block.Data), int(flagOffset)
}
func (dbm *dataBlocksMap) AllInUse() bool {
for blockIndex := uint16(0); blockIndex < DATA_BLOCK_MAP_BLOCKS_COUNT; blockIndex++ {
block, err := dbm.dataBuffer.FetchBlock(DATA_BLOCK_MAP_FIRST_BLOCK + blockIndex)
if err != nil {
panic(err)
}
bitMap := dbio.NewBitMapFromBytes(block.Data)
for i := 0; i < dbio.DATABLOCK_SIZE; i++ {
if isInUse, err := bitMap.Get(i); err != nil {
panic(err)
} else if !isInUse {
return false
}
}
}
return true
}
func (dbm *dataBlocksMap) FirstFree() uint16 {
for blockIndex := uint16(0); blockIndex < DATA_BLOCK_MAP_BLOCKS_COUNT; blockIndex++ {
block, err := dbm.dataBuffer.FetchBlock(DATA_BLOCK_MAP_FIRST_BLOCK + blockIndex)
if err != nil {
panic(err)
}
bitMap := dbio.NewBitMapFromBytes(block.Data)
for i := 0; i < dbio.DATABLOCK_SIZE; i++ {
isInUse, err := bitMap.Get(i)
if err != nil {
panic(err)
}
if !isInUse {
return uint16(i) + blockIndex*dbio.DATABLOCK_SIZE
}
}
}
return 0
}
