github.com/reapchain/go-reapchain@v0.2.15-0.20210609012950-9735c110c705/ethdb/memory_database.go (about)

     1  // Copyright 2014 The go-ethereum Authors
     2  // This file is part of the go-ethereum library.
     3  //
     4  // The go-ethereum library is free software: you can redistribute it and/or modify
     5  // it under the terms of the GNU Lesser General Public License as published by
     6  // the Free Software Foundation, either version 3 of the License, or
     7  // (at your option) any later version.
     8  //
     9  // The go-ethereum library is distributed in the hope that it will be useful,
    10  // but WITHOUT ANY WARRANTY; without even the implied warranty of
    11  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
    12  // GNU Lesser General Public License for more details.
    13  //
    14  // You should have received a copy of the GNU Lesser General Public License
    15  // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
    16  
    17  package ethdb
    18  
    19  import (
    20  	"errors"
    21  	"sync"
    22  
    23  	"github.com/ethereum/go-ethereum/common"
    24  	"github.com/ethereum/go-ethereum/log"
    25  )
    26  
    27  /*
    28   * This is a test memory database. Do not use for any production it does not get persisted
    29   */
    30  type MemDatabase struct {
    31  	db   map[string][]byte
    32  	lock sync.RWMutex
    33  }
    34  
    35  func NewMemDatabase() (*MemDatabase, error) {
    36  	log.Info("NewMemDatabse create",)
    37  	return &MemDatabase{
    38  		db: make(map[string][]byte),
    39  	}, nil
    40  }
    41  
    42  func (db *MemDatabase) Put(key []byte, value []byte) error {
    43  	db.lock.Lock()
    44  	defer db.lock.Unlock()
    45  
    46  	db.db[string(key)] = common.CopyBytes(value)
    47  	return nil
    48  }
    49  
    50  func (db *MemDatabase) Set(key []byte, value []byte) {
    51  	db.lock.Lock()
    52  	defer db.lock.Unlock()
    53  
    54  	db.Put(key, value)
    55  }
    56  
    57  func (db *MemDatabase) Get(key []byte) ([]byte, error) {
    58  	db.lock.RLock()
    59  	defer db.lock.RUnlock()
    60  
    61  	if entry, ok := db.db[string(key)]; ok {
    62  		return entry, nil
    63  	}
    64  	return nil, errors.New("not found")
    65  }
    66  
    67  func (db *MemDatabase) Keys() [][]byte {
    68  	db.lock.RLock()
    69  	defer db.lock.RUnlock()
    70  
    71  	keys := [][]byte{}
    72  	for key := range db.db {
    73  		keys = append(keys, []byte(key))
    74  	}
    75  	return keys
    76  }
    77  
    78  /*
    79  func (db *MemDatabase) GetKeys() []*common.Key {
    80  	data, _ := db.Get([]byte("KeyRing"))
    81  
    82  	return []*common.Key{common.NewKeyFromBytes(data)}
    83  }
    84  */
    85  
    86  func (db *MemDatabase) Delete(key []byte) error {
    87  	db.lock.Lock()
    88  	defer db.lock.Unlock()
    89  
    90  	delete(db.db, string(key))
    91  	return nil
    92  }
    93  
    94  func (db *MemDatabase) Close() {}
    95  
    96  func (db *MemDatabase) NewBatch() Batch {
    97  	return &memBatch{db: db}
    98  }
    99  
   100  type kv struct{ k, v []byte }
   101  
   102  type memBatch struct {
   103  	db     *MemDatabase
   104  	writes []kv
   105  	lock   sync.RWMutex
   106  }
   107  
   108  func (b *memBatch) Put(key, value []byte) error {
   109  	b.lock.Lock()
   110  	defer b.lock.Unlock()
   111  
   112  	b.writes = append(b.writes, kv{common.CopyBytes(key), common.CopyBytes(value)})
   113  	return nil
   114  }
   115  
   116  func (b *memBatch) Write() error {
   117  	b.lock.RLock()
   118  	defer b.lock.RUnlock()
   119  
   120  	b.db.lock.Lock()
   121  	defer b.db.lock.Unlock()
   122  
   123  	for _, kv := range b.writes {
   124  		b.db.db[string(kv.k)] = kv.v
   125  	}
   126  	return nil
   127  }