func (db *DB) Open(name string, createIfMissing bool, maxOpenFiles int,
writeBufSize int, cacheSize int64, compression int) error {
db.opt = C.rocksdb_options_create()
C.rocksdb_options_set_create_if_missing(db.opt, boolToUchar(createIfMissing))
C.rocksdb_options_set_write_buffer_size(db.opt, C.size_t(writeBufSize))
C.rocksdb_options_set_max_open_files(db.opt, C.int(maxOpenFiles))
C.rocksdb_options_set_compression(db.opt, C.int(compression))
var block_options = C.rocksdb_block_based_options_create()
if cacheSize > 0 {
db.cache = C.rocksdb_cache_create_lru(C.size_t(cacheSize))
C.rocksdb_block_based_options_set_block_cache(block_options, db.cache)
} else {
C.rocksdb_block_based_options_set_no_block_cache(block_options, 1)
}
db.fp = C.rocksdb_filterpolicy_create_bloom(10)
C.rocksdb_block_based_options_set_filter_policy(block_options, db.fp)
C.rocksdb_options_set_block_based_table_factory(db.opt, block_options)
cname := C.CString(name)
defer C.free(unsafe.Pointer(cname))
var errStr *C.char
db.db = C.rocksdb_open(db.opt, cname, &errStr)
if errStr != nil {
defer C.free(unsafe.Pointer(errStr))
return errors.New(C.GoString(errStr))
}
db.rOpt = C.rocksdb_readoptions_create()
db.wOpt = C.rocksdb_writeoptions_create()
return nil
}
// createOptions sets the default options for creating, reading, and writing
// from the db. destroyOptions should be called when the options aren't needed
// anymore.
func (r *RocksDB) createOptions() {
// TODO(andybons): Set the cache size.
r.opts = C.rocksdb_options_create()
C.rocksdb_options_set_create_if_missing(r.opts, 1)
r.wOpts = C.rocksdb_writeoptions_create()
r.rOpts = C.rocksdb_readoptions_create()
}
func (db *DB) NewReadOptions(createSnapshot bool) *ReadOptions {
var opt = new(ReadOptions)
opt.rOpt = C.rocksdb_readoptions_create()
if createSnapshot {
opt.snap = C.rocksdb_create_snapshot(db.db)
C.rocksdb_readoptions_set_snapshot(opt.rOpt, opt.snap)
opt.db = db.db
}
return opt
}
// GetSnapshot returns the value for the given key from the given
// snapshotID, nil otherwise.
func (r *RocksDB) GetSnapshot(key Key, snapshotID string) ([]byte, error) {
snapshotHandle, ok := r.snapshots[snapshotID]
if !ok {
return nil, util.Errorf("snapshotID %s does not exist", snapshotID)
}
opts := C.rocksdb_readoptions_create()
C.rocksdb_readoptions_set_snapshot(opts, snapshotHandle)
defer C.rocksdb_readoptions_destroy(opts)
return r.getInternal(key, opts)
}
// createOptions sets the default options for creating, reading, and writing
// from the db. destroyOptions should be called when the options aren't needed
// anymore.
func (r *RocksDB) createOptions() {
// TODO(andybons): Set the cache size.
r.opts = C.rocksdb_options_create()
C.rocksdb_options_set_create_if_missing(r.opts, 1)
// This enables us to use rocksdb_merge with counter semantics.
// See rocksdb.{c,h} for the C implementation.
r.mergeOperator = C.MakeMergeOperator()
C.rocksdb_options_set_merge_operator(r.opts, r.mergeOperator)
r.wOpts = C.rocksdb_writeoptions_create()
r.rOpts = C.rocksdb_readoptions_create()
}
// ScanSnapshot returns up to max key/value objects starting from
// start (inclusive) and ending at end (non-inclusive) from the
// given snapshotID.
// Specify max=0 for unbounded scans.
func (r *RocksDB) ScanSnapshot(start, end Key, max int64, snapshotID string) ([]proto.RawKeyValue, error) {
snapshotHandle, ok := r.snapshots[snapshotID]
if !ok {
return nil, util.Errorf("snapshotID %s does not exist", snapshotID)
}
opts := C.rocksdb_readoptions_create()
C.rocksdb_readoptions_set_fill_cache(opts, 0)
C.rocksdb_readoptions_set_snapshot(opts, snapshotHandle)
defer C.rocksdb_readoptions_destroy(opts)
return r.scanInternal(start, end, max, opts)
}
// Scan returns up to max key/value objects starting from
// start (inclusive) and ending at end (non-inclusive).
// If max is zero then the number of key/values returned is unbounded.
func (r *RocksDB) Scan(start, end Key, max int64) ([]RawKeyValue, error) {
var keyVals []RawKeyValue
if bytes.Compare(start, end) >= 0 {
return keyVals, nil
}
// In order to prevent content displacement, caching is disabled
// when performing scans. Any options set within the shared read
// options field that should be carried over needs to be set here
// as well.
opts := C.rocksdb_readoptions_create()
C.rocksdb_readoptions_set_fill_cache(opts, 0)
defer C.rocksdb_readoptions_destroy(opts)
it := C.rocksdb_create_iterator(r.rdb, opts)
defer C.rocksdb_iter_destroy(it)
byteCount := len(start)
if byteCount == 0 {
// start=Key("") needs special treatment since we need
// to access start[0] in an explicit seek.
C.rocksdb_iter_seek_to_first(it)
} else {
C.rocksdb_iter_seek(it, bytesPointer(start), C.size_t(byteCount))
}
for i := int64(1); C.rocksdb_iter_valid(it) == 1; C.rocksdb_iter_next(it) {
if max > 0 && i > max {
break
}
var l C.size_t
// The data returned by rocksdb_iter_{key,value} is not meant to be
// freed by the client. It is a direct reference to the data managed
// by the iterator, so it is copied instead of freed.
data := C.rocksdb_iter_key(it, &l)
k := C.GoBytes(unsafe.Pointer(data), C.int(l))
if bytes.Compare(k, end) >= 0 {
break
}
data = C.rocksdb_iter_value(it, &l)
v := C.GoBytes(unsafe.Pointer(data), C.int(l))
keyVals = append(keyVals, RawKeyValue{
Key: k,
Value: v,
})
i++
}
// Check for any errors during iteration.
var cErr *C.char
C.rocksdb_iter_get_error(it, &cErr)
if cErr != nil {
return nil, charToErr(cErr)
}
return keyVals, nil
}
// createOptions sets the default options for creating, reading, and writing
// from the db. destroyOptions should be called when the options aren't needed
// anymore.
func (r *RocksDB) createOptions() {
// TODO(andybons): Set the cache size.
r.opts = C.rocksdb_options_create()
C.rocksdb_options_set_create_if_missing(r.opts, 1)
// This enables us to use rocksdb_merge with counter semantics.
// See rocksdb.{c,h} for the C implementation.
r.mergeOperator = C.make_merge_operator()
C.rocksdb_options_set_merge_operator(r.opts, r.mergeOperator)
// This enables garbage collection of transaction and response cache rows.
r.compactionFilterFactory = C.make_gc_compaction_filter_factory(unsafe.Pointer(r))
C.rocksdb_options_set_compaction_filter_factory(r.opts, r.compactionFilterFactory)
r.wOpts = C.rocksdb_writeoptions_create()
r.rOpts = C.rocksdb_readoptions_create()
}
// scan returns up to max key/value objects starting from
// start (inclusive) and ending at end (non-inclusive).
// If max is zero then the number of key/values returned is unbounded.
func (r *RocksDB) scan(start, end Key, max int64) ([]KeyValue, error) {
// In order to prevent content displacement, caching is disabled
// when performing scans. Any options set within the shared read
// options field that should be carried over needs to be set here
// as well.
opts := C.rocksdb_readoptions_create()
C.rocksdb_readoptions_set_fill_cache(opts, 0)
defer C.rocksdb_readoptions_destroy(opts)
it := C.rocksdb_create_iterator(r.rdb, opts)
defer C.rocksdb_iter_destroy(it)
keyVals := []KeyValue{}
C.rocksdb_iter_seek(it, (*C.char)(unsafe.Pointer(&start[0])), C.size_t(len(start)))
for i := int64(1); C.rocksdb_iter_valid(it) == 1; C.rocksdb_iter_next(it) {
if max > 0 && i > max {
break
}
var l C.size_t
// The data returned by rocksdb_iter_{key,value} is not meant to be
// freed by the client. It is a direct reference to the data managed
// by the iterator, so it is copied instead of freed.
data := C.rocksdb_iter_key(it, &l)
k := C.GoBytes(unsafe.Pointer(data), C.int(l))
if bytes.Equal(k, end) {
break
}
data = C.rocksdb_iter_value(it, &l)
v := C.GoBytes(unsafe.Pointer(data), C.int(l))
keyVals = append(keyVals, KeyValue{
Key: k,
Value: Value{Bytes: v},
})
i++
}
// Check for any errors during iteration.
var cErr *C.char
C.rocksdb_iter_get_error(it, &cErr)
if cErr != nil {
return nil, charToErr(cErr)
}
return keyVals, nil
}
// NewReadOptions allocates a new ReadOptions object.
func NewReadOptions() *ReadOptions {
opt := C.rocksdb_readoptions_create()
return &ReadOptions{opt}
}
// NewDefaultReadOptions creates a default ReadOptions object.
func NewDefaultReadOptions() *ReadOptions {
return NewNativeReadOptions(C.rocksdb_readoptions_create())
}
// Scan returns up to max key/value objects starting from
// start (inclusive) and ending at end (non-inclusive).
// If max is zero then the number of key/values returned is unbounded.
func (r *RocksDB) Scan(start, end Key, max int64) ([]proto.RawKeyValue, error) {
opts := C.rocksdb_readoptions_create()
C.rocksdb_readoptions_set_fill_cache(opts, 0)
defer C.rocksdb_readoptions_destroy(opts)
return r.scanInternal(start, end, max, opts)
}
// NewReadOptions creates a default ReadOptions object.
func NewReadOptions() *ReadOptions {
return newNativeReadOptions(C.rocksdb_readoptions_create())
}