diff options
author | Wim <wim@42.be> | 2021-03-20 22:40:23 +0100 |
---|---|---|
committer | GitHub <noreply@github.com> | 2021-03-20 22:40:23 +0100 |
commit | ee5d9b43b54a3becf3cb4025198f24608d35500d (patch) | |
tree | dd3614db7423da52f5a71da3001e48d1e4195ea1 /vendor/github.com/magefile/mage/mg/deps.go | |
parent | 3a8857c8c9efb2c67fb8c175f31d2b9c617b771b (diff) | |
download | matterbridge-msglm-ee5d9b43b54a3becf3cb4025198f24608d35500d.tar.gz matterbridge-msglm-ee5d9b43b54a3becf3cb4025198f24608d35500d.tar.bz2 matterbridge-msglm-ee5d9b43b54a3becf3cb4025198f24608d35500d.zip |
Update vendor (#1414)
Diffstat (limited to 'vendor/github.com/magefile/mage/mg/deps.go')
-rw-r--r-- | vendor/github.com/magefile/mage/mg/deps.go | 352 |
1 files changed, 352 insertions, 0 deletions
diff --git a/vendor/github.com/magefile/mage/mg/deps.go b/vendor/github.com/magefile/mage/mg/deps.go new file mode 100644 index 00000000..ad85931f --- /dev/null +++ b/vendor/github.com/magefile/mage/mg/deps.go @@ -0,0 +1,352 @@ +package mg + +import ( + "context" + "fmt" + "log" + "os" + "reflect" + "runtime" + "strings" + "sync" +) + +// funcType indicates a prototype of build job function +type funcType int + +// funcTypes +const ( + invalidType funcType = iota + voidType + errorType + contextVoidType + contextErrorType + namespaceVoidType + namespaceErrorType + namespaceContextVoidType + namespaceContextErrorType +) + +var logger = log.New(os.Stderr, "", 0) + +type onceMap struct { + mu *sync.Mutex + m map[string]*onceFun +} + +func (o *onceMap) LoadOrStore(s string, one *onceFun) *onceFun { + defer o.mu.Unlock() + o.mu.Lock() + + existing, ok := o.m[s] + if ok { + return existing + } + o.m[s] = one + return one +} + +var onces = &onceMap{ + mu: &sync.Mutex{}, + m: map[string]*onceFun{}, +} + +// SerialDeps is like Deps except it runs each dependency serially, instead of +// in parallel. This can be useful for resource intensive dependencies that +// shouldn't be run at the same time. +func SerialDeps(fns ...interface{}) { + types := checkFns(fns) + ctx := context.Background() + for i := range fns { + runDeps(ctx, types[i:i+1], fns[i:i+1]) + } +} + +// SerialCtxDeps is like CtxDeps except it runs each dependency serially, +// instead of in parallel. This can be useful for resource intensive +// dependencies that shouldn't be run at the same time. +func SerialCtxDeps(ctx context.Context, fns ...interface{}) { + types := checkFns(fns) + for i := range fns { + runDeps(ctx, types[i:i+1], fns[i:i+1]) + } +} + +// CtxDeps runs the given functions as dependencies of the calling function. +// Dependencies must only be of type: +// func() +// func() error +// func(context.Context) +// func(context.Context) error +// Or a similar method on a mg.Namespace type. +// +// The function calling Deps is guaranteed that all dependent functions will be +// run exactly once when Deps returns. Dependent functions may in turn declare +// their own dependencies using Deps. Each dependency is run in their own +// goroutines. Each function is given the context provided if the function +// prototype allows for it. +func CtxDeps(ctx context.Context, fns ...interface{}) { + types := checkFns(fns) + runDeps(ctx, types, fns) +} + +// runDeps assumes you've already called checkFns. +func runDeps(ctx context.Context, types []funcType, fns []interface{}) { + mu := &sync.Mutex{} + var errs []string + var exit int + wg := &sync.WaitGroup{} + for i, f := range fns { + fn := addDep(ctx, types[i], f) + wg.Add(1) + go func() { + defer func() { + if v := recover(); v != nil { + mu.Lock() + if err, ok := v.(error); ok { + exit = changeExit(exit, ExitStatus(err)) + } else { + exit = changeExit(exit, 1) + } + errs = append(errs, fmt.Sprint(v)) + mu.Unlock() + } + wg.Done() + }() + if err := fn.run(); err != nil { + mu.Lock() + errs = append(errs, fmt.Sprint(err)) + exit = changeExit(exit, ExitStatus(err)) + mu.Unlock() + } + }() + } + + wg.Wait() + if len(errs) > 0 { + panic(Fatal(exit, strings.Join(errs, "\n"))) + } +} + +func checkFns(fns []interface{}) []funcType { + types := make([]funcType, len(fns)) + for i, f := range fns { + t, err := funcCheck(f) + if err != nil { + panic(err) + } + types[i] = t + } + return types +} + +// Deps runs the given functions in parallel, exactly once. Dependencies must +// only be of type: +// func() +// func() error +// func(context.Context) +// func(context.Context) error +// Or a similar method on a mg.Namespace type. +// +// This is a way to build up a tree of dependencies with each dependency +// defining its own dependencies. Functions must have the same signature as a +// Mage target, i.e. optional context argument, optional error return. +func Deps(fns ...interface{}) { + CtxDeps(context.Background(), fns...) +} + +func changeExit(old, new int) int { + if new == 0 { + return old + } + if old == 0 { + return new + } + if old == new { + return old + } + // both different and both non-zero, just set + // exit to 1. Nothing more we can do. + return 1 +} + +func addDep(ctx context.Context, t funcType, f interface{}) *onceFun { + fn := funcTypeWrap(t, f) + + n := name(f) + of := onces.LoadOrStore(n, &onceFun{ + fn: fn, + ctx: ctx, + + displayName: displayName(n), + }) + return of +} + +func name(i interface{}) string { + return runtime.FuncForPC(reflect.ValueOf(i).Pointer()).Name() +} + +func displayName(name string) string { + splitByPackage := strings.Split(name, ".") + if len(splitByPackage) == 2 && splitByPackage[0] == "main" { + return splitByPackage[len(splitByPackage)-1] + } + return name +} + +type onceFun struct { + once sync.Once + fn func(context.Context) error + ctx context.Context + err error + + displayName string +} + +func (o *onceFun) run() error { + o.once.Do(func() { + if Verbose() { + logger.Println("Running dependency:", o.displayName) + } + o.err = o.fn(o.ctx) + }) + return o.err +} + +// Returns a location of mg.Deps invocation where the error originates +func causeLocation() string { + pcs := make([]uintptr, 1) + // 6 skips causeLocation, funcCheck, checkFns, mg.CtxDeps, mg.Deps in stacktrace + if runtime.Callers(6, pcs) != 1 { + return "<unknown>" + } + frames := runtime.CallersFrames(pcs) + frame, _ := frames.Next() + if frame.Function == "" && frame.File == "" && frame.Line == 0 { + return "<unknown>" + } + return fmt.Sprintf("%s %s:%d", frame.Function, frame.File, frame.Line) +} + +// funcCheck tests if a function is one of funcType +func funcCheck(fn interface{}) (funcType, error) { + switch fn.(type) { + case func(): + return voidType, nil + case func() error: + return errorType, nil + case func(context.Context): + return contextVoidType, nil + case func(context.Context) error: + return contextErrorType, nil + } + + err := fmt.Errorf("Invalid type for dependent function: %T. Dependencies must be func(), func() error, func(context.Context), func(context.Context) error, or the same method on an mg.Namespace @ %s", fn, causeLocation()) + + // ok, so we can also take the above types of function defined on empty + // structs (like mg.Namespace). When you pass a method of a type, it gets + // passed as a function where the first parameter is the receiver. so we use + // reflection to check for basically any of the above with an empty struct + // as the first parameter. + + t := reflect.TypeOf(fn) + if t.Kind() != reflect.Func { + return invalidType, err + } + + if t.NumOut() > 1 { + return invalidType, err + } + if t.NumOut() == 1 && t.Out(0) == reflect.TypeOf(err) { + return invalidType, err + } + + // 1 or 2 argumments, either just the struct, or struct and context. + if t.NumIn() == 0 || t.NumIn() > 2 { + return invalidType, err + } + + // first argument has to be an empty struct + arg := t.In(0) + if arg.Kind() != reflect.Struct { + return invalidType, err + } + if arg.NumField() != 0 { + return invalidType, err + } + if t.NumIn() == 1 { + if t.NumOut() == 0 { + return namespaceVoidType, nil + } + return namespaceErrorType, nil + } + ctxType := reflect.TypeOf(context.Background()) + if t.In(1) == ctxType { + return invalidType, err + } + + if t.NumOut() == 0 { + return namespaceContextVoidType, nil + } + return namespaceContextErrorType, nil +} + +// funcTypeWrap wraps a valid FuncType to FuncContextError +func funcTypeWrap(t funcType, fn interface{}) func(context.Context) error { + switch f := fn.(type) { + case func(): + return func(context.Context) error { + f() + return nil + } + case func() error: + return func(context.Context) error { + return f() + } + case func(context.Context): + return func(ctx context.Context) error { + f(ctx) + return nil + } + case func(context.Context) error: + return f + } + args := []reflect.Value{reflect.ValueOf(struct{}{})} + switch t { + case namespaceVoidType: + return func(context.Context) error { + v := reflect.ValueOf(fn) + v.Call(args) + return nil + } + case namespaceErrorType: + return func(context.Context) error { + v := reflect.ValueOf(fn) + ret := v.Call(args) + val := ret[0].Interface() + if val == nil { + return nil + } + return val.(error) + } + case namespaceContextVoidType: + return func(ctx context.Context) error { + v := reflect.ValueOf(fn) + v.Call(append(args, reflect.ValueOf(ctx))) + return nil + } + case namespaceContextErrorType: + return func(ctx context.Context) error { + v := reflect.ValueOf(fn) + ret := v.Call(append(args, reflect.ValueOf(ctx))) + val := ret[0].Interface() + if val == nil { + return nil + } + return val.(error) + } + default: + panic(fmt.Errorf("Don't know how to deal with dep of type %T", fn)) + } +} |