path: root/block_pool.go

package eth

import (
    "math"
    "math/big"
    "sync"

    "github.com/ethereum/eth-go/ethchain"
    "github.com/ethereum/eth-go/ethutil"
)

type block struct {
    peer  *Peer
    block *ethchain.Block
}

type BlockPool struct {
    mut sync.Mutex

    eth *Ethereum

    hashPool [][]byte
    pool     map[string]*block

    td *big.Int
}

func NewBlockPool(eth *Ethereum) *BlockPool {
    return &BlockPool{
        eth:  eth,
        pool: make(map[string]*block),
        td:   ethutil.Big0,
    }
}

func (self *BlockPool) HasLatestHash() bool {
    return self.pool[string(self.eth.BlockChain().CurrentBlock.Hash())] != nil
}

func (self *BlockPool) HasCommonHash(hash []byte) bool {
    return self.eth.BlockChain().GetBlock(hash) != nil
}

func (self *BlockPool) AddHash(hash []byte) {
    if self.pool[string(hash)] == nil {
        self.pool[string(hash)] = &block{nil, nil}

        self.hashPool = append([][]byte{hash}, self.hashPool...)
    }
}

func (self *BlockPool) SetBlock(b *ethchain.Block, peer *Peer) {
    hash := string(b.Hash())

    if self.pool[hash] == nil {
        self.pool[hash] = &block{peer, nil}
    }

    self.pool[hash].block = b
}

func (self *BlockPool) CheckLinkAndProcess(f func(block *ethchain.Block)) bool {
    self.mut.Lock()
    defer self.mut.Unlock()

    if self.IsLinked() {
        for i, hash := range self.hashPool {
            if self.pool[string(hash)] == nil {
                continue
            }

            block := self.pool[string(hash)].block
            if block != nil {
                f(block)

                delete(self.pool, string(hash))
            } else {
                self.hashPool = self.hashPool[i:]

                return false
            }
        }

        return true
    }

    return false
}

func (self *BlockPool) IsLinked() bool {
    if len(self.hashPool) == 0 {
        return false
    }

    for i := 0; i < len(self.hashPool); i++ {
        item := self.pool[string(self.hashPool[i])]
        if item != nil && item.block != nil {
            if self.eth.BlockChain().HasBlock(item.block.PrevHash) {
                self.hashPool = self.hashPool[i:]

                return true
            }
        }
    }

    return false
}

func (self *BlockPool) Take(amount int, peer *Peer) (hashes [][]byte) {
    self.mut.Lock()
    defer self.mut.Unlock()

    num := int(math.Min(float64(amount), float64(len(self.pool))))
    j := 0
    for i := 0; i < len(self.hashPool) && j < num; i++ {
        hash := string(self.hashPool[i])
        if self.pool[hash] != nil && (self.pool[hash].peer == nil || self.pool[hash].peer == peer) && self.pool[hash].block == nil {
            self.pool[hash].peer = peer

            hashes = append(hashes, self.hashPool[i])
            j++
        }
    }

    return
}