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-rw-r--r--vendor/github.com/lrstanley/girc/internal/ctxgroup/ctxgroup.go67
1 files changed, 67 insertions, 0 deletions
diff --git a/vendor/github.com/lrstanley/girc/internal/ctxgroup/ctxgroup.go b/vendor/github.com/lrstanley/girc/internal/ctxgroup/ctxgroup.go
new file mode 100644
index 00000000..e66ed2b5
--- /dev/null
+++ b/vendor/github.com/lrstanley/girc/internal/ctxgroup/ctxgroup.go
@@ -0,0 +1,67 @@
+// Copyright (c) Liam Stanley <me@liamstanley.io>. All rights reserved. Use
+// of this source code is governed by the MIT license that can be found in
+// the LICENSE file.
+
+package ctxgroup
+
+import (
+ "context"
+ "sync"
+)
+
+// A Group is a collection of goroutines working on subtasks that are part of
+// the same overall task.
+type Group struct {
+ ctx context.Context
+ cancel func()
+
+ wg sync.WaitGroup
+
+ errOnce sync.Once
+ err error
+}
+
+// New returns a new Group and an associated context derived from ctx.
+// Obtain the derived context from calling Group.Context().
+//
+// The derived context is canceled the first time a function passed to Go
+// returns a non-nil error or the first time Wait returns, whichever occurs
+// first.
+func New(ctx context.Context) *Group {
+ nctx, cancel := context.WithCancel(ctx)
+ return &Group{ctx: nctx, cancel: cancel}
+}
+
+// Context returns the context for this group. It may be canceled by the first
+// function to return a non-nil error.
+func (g *Group) Context() context.Context {
+ return g.ctx
+}
+
+// Wait blocks until all function calls from the Go method have returned, then
+// returns the first non-nil error (if any) from them.
+func (g *Group) Wait() error {
+ g.wg.Wait()
+ if g.cancel != nil {
+ g.cancel()
+ }
+ return g.err
+}
+
+// Go calls the given function in a new goroutine. The first call to return a
+// non-nil error cancels the group; its error will be returned by Wait.
+func (g *Group) Go(f func(ctx context.Context) error) {
+ g.wg.Add(1)
+ go func() {
+ defer g.wg.Done()
+
+ if err := f(g.ctx); err != nil {
+ g.errOnce.Do(func() {
+ g.err = err
+ if g.cancel != nil {
+ g.cancel()
+ }
+ })
+ }
+ }()
+}