status-go/services/wallet/concurrent.go

82 lines
2.0 KiB
Go

package wallet
import (
"context"
"math/big"
"sync"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/log"
)
// NewConcurrentDownloader creates ConcurrentDownloader instance.
func NewConcurrentDownloader(ctx context.Context) *ConcurrentDownloader {
runner := NewAtomicGroup(ctx)
result := &Result{}
return &ConcurrentDownloader{runner, result}
}
type ConcurrentDownloader struct {
*AtomicGroup
*Result
}
type Result struct {
mu sync.Mutex
transfers []Transfer
}
func (r *Result) Push(transfers ...Transfer) {
r.mu.Lock()
defer r.mu.Unlock()
r.transfers = append(r.transfers, transfers...)
}
func (r *Result) Get() []Transfer {
r.mu.Lock()
defer r.mu.Unlock()
rst := make([]Transfer, len(r.transfers))
copy(rst, r.transfers)
return rst
}
// TransferDownloader downloads transfers from single block using number.
type TransferDownloader interface {
GetTransfersByNumber(context.Context, *big.Int) ([]Transfer, error)
}
func downloadEthConcurrently(c *ConcurrentDownloader, client BalanceReader, downloader TransferDownloader, account common.Address, low, high *big.Int) {
c.Add(func(ctx context.Context) error {
if low.Cmp(high) >= 0 {
return nil
}
log.Debug("eth transfers comparing blocks", "low", low, "high", high)
lb, err := client.BalanceAt(ctx, account, low)
if err != nil {
return err
}
hb, err := client.BalanceAt(ctx, account, high)
if err != nil {
return err
}
if lb.Cmp(hb) == 0 {
log.Debug("balances are equal", "low", low, "high", high)
return nil
}
if new(big.Int).Sub(high, low).Cmp(one) == 0 {
transfers, err := downloader.GetTransfersByNumber(ctx, high)
if err != nil {
return err
}
c.Push(transfers...)
return nil
}
mid := new(big.Int).Add(low, high)
mid = mid.Div(mid, two)
log.Debug("balances are not equal. spawn two concurrent downloaders", "low", low, "mid", mid, "high", high)
downloadEthConcurrently(c, client, downloader, account, low, mid)
downloadEthConcurrently(c, client, downloader, account, mid, high)
return nil
})
}