53 lines
1.3 KiB
Go
53 lines
1.3 KiB
Go
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// Copyright (C) 2018 Storj Labs, Inc.
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// See LICENSE for copying information.
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package server
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import "github.com/zeebo/errs"
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// AllocationManager manages allocations for file retrieval
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type AllocationManager struct {
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TotalAllocated, Used int64
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}
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// NewAllocationManager returns a new AllocationManager
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func NewAllocationManager() *AllocationManager {
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return &AllocationManager{}
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}
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// AllocationError is a type of error for failures in AllocationManager
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var AllocationError = errs.Class("allocation error")
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// NextReadSize returns the size to be read from file based on max that can be Used
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func (am *AllocationManager) NextReadSize() int64 {
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if am.TotalAllocated <= 0 {
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return 0
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}
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remaining := am.TotalAllocated - am.Used
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if remaining > 32*1024 {
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return 32 * 1024
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}
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return remaining
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}
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// NewTotal adds another allcoation to the AllocationManager
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func (am *AllocationManager) NewTotal(total int64) {
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if total > am.TotalAllocated {
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am.TotalAllocated = total
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}
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}
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// UseAllocation indicates to the AllocationManager that an Amount was successfully Used for an allocation
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func (am *AllocationManager) UseAllocation(amount int64) error {
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if amount > am.TotalAllocated-am.Used {
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return AllocationError.New("can't use unallocated bandwidth")
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}
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am.Used += amount
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return nil
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}
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