ceph-csi/vendor/google.golang.org/appengine/internal/net.go
Niels de Vos 91774fc936 rebase: vendor dependencies for Vault API
Uses github.com/libopenstorage/secrets to communicate with Vault. This
removes the need for maintaining our own limited Vault APIs.

By adding the new dependency, several other packages got updated in the
process. Unused indirect dependencies have been removed from go.mod.

Signed-off-by: Niels de Vos <ndevos@redhat.com>
2020-11-29 04:03:59 +00:00

57 lines
1.2 KiB
Go

// Copyright 2014 Google Inc. All rights reserved.
// Use of this source code is governed by the Apache 2.0
// license that can be found in the LICENSE file.
package internal
// This file implements a network dialer that limits the number of concurrent connections.
// It is only used for API calls.
import (
"log"
"net"
"runtime"
"sync"
"time"
)
var limitSem = make(chan int, 100) // TODO(dsymonds): Use environment variable.
func limitRelease() {
// non-blocking
select {
case <-limitSem:
default:
// This should not normally happen.
log.Print("appengine: unbalanced limitSem release!")
}
}
func limitDial(network, addr string) (net.Conn, error) {
limitSem <- 1
// Dial with a timeout in case the API host is MIA.
// The connection should normally be very fast.
conn, err := net.DialTimeout(network, addr, 500*time.Millisecond)
if err != nil {
limitRelease()
return nil, err
}
lc := &limitConn{Conn: conn}
runtime.SetFinalizer(lc, (*limitConn).Close) // shouldn't usually be required
return lc, nil
}
type limitConn struct {
close sync.Once
net.Conn
}
func (lc *limitConn) Close() error {
defer lc.close.Do(func() {
limitRelease()
runtime.SetFinalizer(lc, nil)
})
return lc.Conn.Close()
}