/
utils.go
53 lines (47 loc) · 1.35 KB
/
utils.go
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// Copyright (C) 2020-2021, IrineSistiana
//
// This file is part of mosdns.
//
// mosdns is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) or later version.
//
// mosdns is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <https://www.gnu.org/licenses/>.
package handler
import "context"
func ExecChainNode(ctx context.Context, qCtx *Context, n ExecutableChainNode) error {
if n == nil {
return nil
}
// TODO: Error logging
return n.Exec(ctx, qCtx, n.Next())
}
// FirstNode returns the first node of chain of n.
func FirstNode(n ExecutableChainNode) ExecutableChainNode {
p := n
for {
if pn := p.Previous(); pn == nil {
return p
} else {
p = pn
}
}
}
// LastNode returns the Latest node of chain of n.
func LastNode(n ExecutableChainNode) ExecutableChainNode {
p := n
for {
if nn := p.Next(); nn == nil {
return p
} else {
p = nn
}
}
}