syncthing/model/blockqueue.go
2014-07-24 09:56:54 +02:00

74 lines
1.5 KiB
Go

// Copyright (C) 2014 Jakob Borg and Contributors (see the CONTRIBUTORS file).
// All rights reserved. Use of this source code is governed by an MIT-style
// license that can be found in the LICENSE file.
package model
import "github.com/calmh/syncthing/protocol"
type bqAdd struct {
file protocol.FileInfo
have []protocol.BlockInfo
need []protocol.BlockInfo
}
type bqBlock struct {
file protocol.FileInfo
block protocol.BlockInfo // get this block from the network
copy []protocol.BlockInfo // copy these blocks from the old version of the file
first bool
last bool
}
type blockQueue struct {
queued []bqBlock
}
func (q *blockQueue) put(a bqAdd) {
// If we already have it queued, return
for _, b := range q.queued {
if b.file.Name == a.file.Name {
return
}
}
l := len(a.need)
if len(a.have) > 0 {
// First queue a copy operation
q.queued = append(q.queued, bqBlock{
file: a.file,
copy: a.have,
first: true,
last: l == 0,
})
}
// Queue the needed blocks individually
for i, b := range a.need {
q.queued = append(q.queued, bqBlock{
file: a.file,
block: b,
first: len(a.have) == 0 && i == 0,
last: i == l-1,
})
}
if len(a.need)+len(a.have) == 0 {
// If we didn't have anything to fetch, queue an empty block with the "last" flag set to close the file.
q.queued = append(q.queued, bqBlock{
file: a.file,
last: true,
})
}
}
func (q *blockQueue) get() (bqBlock, bool) {
if len(q.queued) == 0 {
return bqBlock{}, false
}
b := q.queued[0]
q.queued = q.queued[1:]
return b, true
}