70 lines
1.8 KiB
Go
70 lines
1.8 KiB
Go
/*
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Maddy Mail Server - Composable all-in-one email server.
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Copyright © 2019-2020 Max Mazurov <fox.cpp@disroot.org>, Maddy Mail Server contributors
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This program is free software: you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation, either version 3 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program. If not, see <https://www.gnu.org/licenses/>.
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*/
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package limiters
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import "context"
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// MultiLimit wraps multiple L implementations into a single one, locking them
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// in the specified order.
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//
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// It does not implement any deadlock detection or avoidance algorithms.
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type MultiLimit struct {
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Wrapped []L
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}
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func (ml *MultiLimit) Take() bool {
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for i := 0; i < len(ml.Wrapped); i++ {
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if !ml.Wrapped[i].Take() {
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// Acquire failed, undo acquire for all other resources we already
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// got.
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for _, l := range ml.Wrapped[:i] {
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l.Release()
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}
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return false
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}
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}
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return true
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}
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func (ml *MultiLimit) TakeContext(ctx context.Context) error {
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for i := 0; i < len(ml.Wrapped); i++ {
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if err := ml.Wrapped[i].TakeContext(ctx); err != nil {
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// Acquire failed, undo acquire for all other resources we already
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// got.
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for _, l := range ml.Wrapped[:i] {
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l.Release()
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}
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return err
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}
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}
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return nil
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}
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func (ml *MultiLimit) Release() {
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for _, l := range ml.Wrapped {
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l.Release()
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}
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}
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func (ml *MultiLimit) Close() {
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for _, l := range ml.Wrapped {
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l.Close()
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}
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}
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