ledisdb/store/leveldb/batch.go

100 lines
2.0 KiB
Go

// +build leveldb
package leveldb
// #cgo LDFLAGS: -lleveldb
// #include "leveldb/c.h"
// #include "leveldb_ext.h"
import "C"
import (
"unsafe"
"github.com/syndtr/goleveldb/leveldb"
)
type WriteBatch struct {
db *DB
wbatch *C.leveldb_writebatch_t
}
func newWriteBatch(db *DB) *WriteBatch {
w := new(WriteBatch)
w.db = db
w.wbatch = C.leveldb_writebatch_create()
return w
}
func (w *WriteBatch) Close() {
if w.wbatch != nil {
C.leveldb_writebatch_destroy(w.wbatch)
w.wbatch = nil
}
}
func (w *WriteBatch) Put(key, value []byte) {
var k, v *C.char
if len(key) != 0 {
k = (*C.char)(unsafe.Pointer(&key[0]))
}
if len(value) != 0 {
v = (*C.char)(unsafe.Pointer(&value[0]))
}
lenk := len(key)
lenv := len(value)
C.leveldb_writebatch_put(w.wbatch, k, C.size_t(lenk), v, C.size_t(lenv))
}
func (w *WriteBatch) Delete(key []byte) {
C.leveldb_writebatch_delete(w.wbatch,
(*C.char)(unsafe.Pointer(&key[0])), C.size_t(len(key)))
}
func (w *WriteBatch) Commit() error {
return w.commit(w.db.writeOpts)
}
func (w *WriteBatch) SyncCommit() error {
return w.commit(w.db.syncOpts)
}
func (w *WriteBatch) Rollback() error {
C.leveldb_writebatch_clear(w.wbatch)
return nil
}
func (w *WriteBatch) commit(wb *WriteOptions) error {
var errStr *C.char
C.leveldb_write(w.db.db, wb.Opt, w.wbatch, &errStr)
if errStr != nil {
return saveError(errStr)
}
return nil
}
//export leveldb_writebatch_iterate_put
func leveldb_writebatch_iterate_put(p unsafe.Pointer, k *C.char, klen C.size_t, v *C.char, vlen C.size_t) {
b := (*leveldb.Batch)(p)
key := slice(unsafe.Pointer(k), int(klen))
value := slice(unsafe.Pointer(v), int(vlen))
b.Put(key, value)
}
//export leveldb_writebatch_iterate_delete
func leveldb_writebatch_iterate_delete(p unsafe.Pointer, k *C.char, klen C.size_t) {
b := (*leveldb.Batch)(p)
key := slice(unsafe.Pointer(k), int(klen))
b.Delete(key)
}
func (w *WriteBatch) Data() []byte {
gbatch := leveldb.Batch{}
C.leveldb_writebatch_iterate_ext(w.wbatch,
unsafe.Pointer(&gbatch))
return gbatch.Dump()
}