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authoruzhas <uzhas@ydb.tech>2023-11-16 16:04:50 +0300
committeruzhas <uzhas@ydb.tech>2023-11-16 17:46:46 +0300
commit46f0c0079bb50609d2eeb6586642bcf114fc5239 (patch)
tree84e4e4978d57fe5de321ba69bf9d0c290de60a66 /vendor/golang.org/x/sync
parent73045e389397816cc2bdd6cd7818b4bce427b265 (diff)
downloadydb-46f0c0079bb50609d2eeb6586642bcf114fc5239.tar.gz
enable ya make for go projects
Diffstat (limited to 'vendor/golang.org/x/sync')
-rw-r--r--vendor/golang.org/x/sync/errgroup/errgroup.go132
-rw-r--r--vendor/golang.org/x/sync/errgroup/go120.go14
-rw-r--r--vendor/golang.org/x/sync/errgroup/ya.make20
-rw-r--r--vendor/golang.org/x/sync/semaphore/semaphore.go136
-rw-r--r--vendor/golang.org/x/sync/semaphore/ya.make19
5 files changed, 321 insertions, 0 deletions
diff --git a/vendor/golang.org/x/sync/errgroup/errgroup.go b/vendor/golang.org/x/sync/errgroup/errgroup.go
new file mode 100644
index 0000000000..b18efb743f
--- /dev/null
+++ b/vendor/golang.org/x/sync/errgroup/errgroup.go
@@ -0,0 +1,132 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package errgroup provides synchronization, error propagation, and Context
+// cancelation for groups of goroutines working on subtasks of a common task.
+package errgroup
+
+import (
+ "context"
+ "fmt"
+ "sync"
+)
+
+type token struct{}
+
+// A Group is a collection of goroutines working on subtasks that are part of
+// the same overall task.
+//
+// A zero Group is valid, has no limit on the number of active goroutines,
+// and does not cancel on error.
+type Group struct {
+ cancel func(error)
+
+ wg sync.WaitGroup
+
+ sem chan token
+
+ errOnce sync.Once
+ err error
+}
+
+func (g *Group) done() {
+ if g.sem != nil {
+ <-g.sem
+ }
+ g.wg.Done()
+}
+
+// WithContext returns a new Group and an associated Context derived from ctx.
+//
+// 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 WithContext(ctx context.Context) (*Group, context.Context) {
+ ctx, cancel := withCancelCause(ctx)
+ return &Group{cancel: cancel}, 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(g.err)
+ }
+ return g.err
+}
+
+// Go calls the given function in a new goroutine.
+// It blocks until the new goroutine can be added without the number of
+// active goroutines in the group exceeding the configured limit.
+//
+// The first call to return a non-nil error cancels the group's context, if the
+// group was created by calling WithContext. The error will be returned by Wait.
+func (g *Group) Go(f func() error) {
+ if g.sem != nil {
+ g.sem <- token{}
+ }
+
+ g.wg.Add(1)
+ go func() {
+ defer g.done()
+
+ if err := f(); err != nil {
+ g.errOnce.Do(func() {
+ g.err = err
+ if g.cancel != nil {
+ g.cancel(g.err)
+ }
+ })
+ }
+ }()
+}
+
+// TryGo calls the given function in a new goroutine only if the number of
+// active goroutines in the group is currently below the configured limit.
+//
+// The return value reports whether the goroutine was started.
+func (g *Group) TryGo(f func() error) bool {
+ if g.sem != nil {
+ select {
+ case g.sem <- token{}:
+ // Note: this allows barging iff channels in general allow barging.
+ default:
+ return false
+ }
+ }
+
+ g.wg.Add(1)
+ go func() {
+ defer g.done()
+
+ if err := f(); err != nil {
+ g.errOnce.Do(func() {
+ g.err = err
+ if g.cancel != nil {
+ g.cancel(g.err)
+ }
+ })
+ }
+ }()
+ return true
+}
+
+// SetLimit limits the number of active goroutines in this group to at most n.
+// A negative value indicates no limit.
+//
+// Any subsequent call to the Go method will block until it can add an active
+// goroutine without exceeding the configured limit.
+//
+// The limit must not be modified while any goroutines in the group are active.
+func (g *Group) SetLimit(n int) {
+ if n < 0 {
+ g.sem = nil
+ return
+ }
+ if len(g.sem) != 0 {
+ panic(fmt.Errorf("errgroup: modify limit while %v goroutines in the group are still active", len(g.sem)))
+ }
+ g.sem = make(chan token, n)
+}
diff --git a/vendor/golang.org/x/sync/errgroup/go120.go b/vendor/golang.org/x/sync/errgroup/go120.go
new file mode 100644
index 0000000000..7d419d3760
--- /dev/null
+++ b/vendor/golang.org/x/sync/errgroup/go120.go
@@ -0,0 +1,14 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build go1.20
+// +build go1.20
+
+package errgroup
+
+import "context"
+
+func withCancelCause(parent context.Context) (context.Context, func(error)) {
+ return context.WithCancelCause(parent)
+}
diff --git a/vendor/golang.org/x/sync/errgroup/ya.make b/vendor/golang.org/x/sync/errgroup/ya.make
new file mode 100644
index 0000000000..c63b60eb54
--- /dev/null
+++ b/vendor/golang.org/x/sync/errgroup/ya.make
@@ -0,0 +1,20 @@
+GO_LIBRARY()
+
+LICENSE(BSD-3-Clause)
+
+SRCS(
+ errgroup.go
+ go120.go
+)
+
+GO_XTEST_SRCS(
+ errgroup_example_md5all_test.go
+ errgroup_test.go
+ go120_test.go
+)
+
+END()
+
+RECURSE(
+ gotest
+)
diff --git a/vendor/golang.org/x/sync/semaphore/semaphore.go b/vendor/golang.org/x/sync/semaphore/semaphore.go
new file mode 100644
index 0000000000..30f632c577
--- /dev/null
+++ b/vendor/golang.org/x/sync/semaphore/semaphore.go
@@ -0,0 +1,136 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package semaphore provides a weighted semaphore implementation.
+package semaphore // import "golang.org/x/sync/semaphore"
+
+import (
+ "container/list"
+ "context"
+ "sync"
+)
+
+type waiter struct {
+ n int64
+ ready chan<- struct{} // Closed when semaphore acquired.
+}
+
+// NewWeighted creates a new weighted semaphore with the given
+// maximum combined weight for concurrent access.
+func NewWeighted(n int64) *Weighted {
+ w := &Weighted{size: n}
+ return w
+}
+
+// Weighted provides a way to bound concurrent access to a resource.
+// The callers can request access with a given weight.
+type Weighted struct {
+ size int64
+ cur int64
+ mu sync.Mutex
+ waiters list.List
+}
+
+// Acquire acquires the semaphore with a weight of n, blocking until resources
+// are available or ctx is done. On success, returns nil. On failure, returns
+// ctx.Err() and leaves the semaphore unchanged.
+//
+// If ctx is already done, Acquire may still succeed without blocking.
+func (s *Weighted) Acquire(ctx context.Context, n int64) error {
+ s.mu.Lock()
+ if s.size-s.cur >= n && s.waiters.Len() == 0 {
+ s.cur += n
+ s.mu.Unlock()
+ return nil
+ }
+
+ if n > s.size {
+ // Don't make other Acquire calls block on one that's doomed to fail.
+ s.mu.Unlock()
+ <-ctx.Done()
+ return ctx.Err()
+ }
+
+ ready := make(chan struct{})
+ w := waiter{n: n, ready: ready}
+ elem := s.waiters.PushBack(w)
+ s.mu.Unlock()
+
+ select {
+ case <-ctx.Done():
+ err := ctx.Err()
+ s.mu.Lock()
+ select {
+ case <-ready:
+ // Acquired the semaphore after we were canceled. Rather than trying to
+ // fix up the queue, just pretend we didn't notice the cancelation.
+ err = nil
+ default:
+ isFront := s.waiters.Front() == elem
+ s.waiters.Remove(elem)
+ // If we're at the front and there're extra tokens left, notify other waiters.
+ if isFront && s.size > s.cur {
+ s.notifyWaiters()
+ }
+ }
+ s.mu.Unlock()
+ return err
+
+ case <-ready:
+ return nil
+ }
+}
+
+// TryAcquire acquires the semaphore with a weight of n without blocking.
+// On success, returns true. On failure, returns false and leaves the semaphore unchanged.
+func (s *Weighted) TryAcquire(n int64) bool {
+ s.mu.Lock()
+ success := s.size-s.cur >= n && s.waiters.Len() == 0
+ if success {
+ s.cur += n
+ }
+ s.mu.Unlock()
+ return success
+}
+
+// Release releases the semaphore with a weight of n.
+func (s *Weighted) Release(n int64) {
+ s.mu.Lock()
+ s.cur -= n
+ if s.cur < 0 {
+ s.mu.Unlock()
+ panic("semaphore: released more than held")
+ }
+ s.notifyWaiters()
+ s.mu.Unlock()
+}
+
+func (s *Weighted) notifyWaiters() {
+ for {
+ next := s.waiters.Front()
+ if next == nil {
+ break // No more waiters blocked.
+ }
+
+ w := next.Value.(waiter)
+ if s.size-s.cur < w.n {
+ // Not enough tokens for the next waiter. We could keep going (to try to
+ // find a waiter with a smaller request), but under load that could cause
+ // starvation for large requests; instead, we leave all remaining waiters
+ // blocked.
+ //
+ // Consider a semaphore used as a read-write lock, with N tokens, N
+ // readers, and one writer. Each reader can Acquire(1) to obtain a read
+ // lock. The writer can Acquire(N) to obtain a write lock, excluding all
+ // of the readers. If we allow the readers to jump ahead in the queue,
+ // the writer will starve — there is always one token available for every
+ // reader.
+ break
+ }
+
+ s.cur += w.n
+ s.waiters.Remove(next)
+ close(w.ready)
+ }
+}
diff --git a/vendor/golang.org/x/sync/semaphore/ya.make b/vendor/golang.org/x/sync/semaphore/ya.make
new file mode 100644
index 0000000000..ee30bd9750
--- /dev/null
+++ b/vendor/golang.org/x/sync/semaphore/ya.make
@@ -0,0 +1,19 @@
+GO_LIBRARY()
+
+LICENSE(BSD-3-Clause)
+
+SRCS(
+ semaphore.go
+)
+
+GO_XTEST_SRCS(
+ semaphore_bench_test.go
+ semaphore_example_test.go
+ semaphore_test.go
+)
+
+END()
+
+RECURSE(
+ gotest
+)