Files
llgo/x/io/io.go
2024-07-29 10:46:14 +08:00

200 lines
3.3 KiB
Go

/*
* Copyright (c) 2024 The GoPlus Authors (goplus.org). All rights reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package io
import (
"log"
"sync"
_ "unsafe"
)
const (
LLGoPackage = "decl"
)
var debugAsync = false
type Void = [0]byte
// -----------------------------------------------------------------------------
type asyncCall interface {
parent() asyncCall
Resume()
Call()
Done() bool
}
type AsyncCall[OutT any] interface {
Resume()
}
type executor struct {
acs []asyncCall
mu sync.Mutex
cond *sync.Cond
}
func newExecutor() *executor {
e := &executor{}
e.cond = sync.NewCond(&e.mu)
return e
}
func (e *executor) schedule(ac asyncCall) {
e.mu.Lock()
e.acs = append(e.acs, ac)
e.mu.Unlock()
e.cond.Signal()
}
func Run[OutT any](ac AsyncCall[OutT]) OutT {
e := newExecutor()
p := ac.(*Promise[OutT])
p.Exec = e
var rootAc asyncCall = p
e.schedule(rootAc)
for {
e.mu.Lock()
for len(e.acs) == 0 {
e.cond.Wait()
}
e.mu.Unlock()
ac := e.acs[0]
e.acs = e.acs[1:]
ac.Call()
if ac.Done() && ac == rootAc {
return p.value
}
}
}
// -----------------------------------------------------------------------------
type R1[T any] struct {
V1 T
}
func (r R1[T]) Values() T {
return r.V1
}
type R2[T1 any, T2 any] struct {
V1 T1
V2 T2
}
func (r R2[T1, T2]) Values() (T1, T2) {
return r.V1, r.V2
}
type R3[T1 any, T2 any, T3 any] struct {
V1 T1
V2 T2
V3 T3
}
func (r R3[T1, T2, T3]) Values() (T1, T2, T3) {
return r.V1, r.V2, r.V3
}
type R4[T1 any, T2 any, T3 any, T4 any] struct {
V1 T1
V2 T2
V3 T3
V4 T4
}
func (r R4[T1, T2, T3, T4]) Values() (T1, T2, T3, T4) {
return r.V1, r.V2, r.V3, r.V4
}
type Promise[TOut any] struct {
Debug string
Next int
Exec *executor
Parent asyncCall
Func func()
value TOut
c chan TOut
}
func NewPromise[TOut any](fn func()) *Promise[TOut] {
return &Promise[TOut]{Func: fn}
}
func (p *Promise[TOut]) parent() asyncCall {
return p.Parent
}
func (p *Promise[TOut]) Resume() {
if debugAsync {
log.Printf("Resume task: %+v\n", p)
}
p.Exec.schedule(p)
}
func (p *Promise[TOut]) Done() bool {
return p.Next == -1
}
func (p *Promise[TOut]) Call() {
p.Func()
}
func (p *Promise[TOut]) Return(v TOut) {
// TODO(lijie): panic if already resolved
p.value = v
if p.c != nil {
p.c <- v
}
if debugAsync {
log.Printf("Return task: %+v\n", p)
}
if p.Parent != nil {
p.Parent.Resume()
}
}
func (p *Promise[TOut]) Yield(v TOut) {
p.value = v
if debugAsync {
log.Printf("Yield task: %+v\n", p)
}
if p.Parent != nil {
p.Parent.Resume()
}
}
func (p *Promise[TOut]) Value() TOut {
return p.value
}
func (p *Promise[TOut]) Chan() <-chan TOut {
if p.c == nil {
p.c = make(chan TOut, 1)
p.Func()
}
return p.c
}
func (p *Promise[TOut]) Await() (ret TOut) {
panic("should not called")
}