First Commit of Voltha-Go-Controller from Radisys
Change-Id: I8e2e908e7ab09a4fe3d86849da18b6d69dcf4ab0
diff --git a/vendor/golang.org/x/net/http2/client_conn_pool.go b/vendor/golang.org/x/net/http2/client_conn_pool.go
new file mode 100644
index 0000000..652bc11
--- /dev/null
+++ b/vendor/golang.org/x/net/http2/client_conn_pool.go
@@ -0,0 +1,313 @@
+// Copyright 2015 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.
+
+// Transport code's client connection pooling.
+
+package http2
+
+import (
+ "context"
+ "crypto/tls"
+ "errors"
+ "net/http"
+ "sync"
+)
+
+// ClientConnPool manages a pool of HTTP/2 client connections.
+type ClientConnPool interface {
+ GetClientConn(req *http.Request, addr string) (*ClientConn, error)
+ MarkDead(*ClientConn)
+}
+
+// clientConnPoolIdleCloser is the interface implemented by ClientConnPool
+// implementations which can close their idle connections.
+type clientConnPoolIdleCloser interface {
+ ClientConnPool
+ closeIdleConnections()
+}
+
+var (
+ _ clientConnPoolIdleCloser = (*clientConnPool)(nil)
+ _ clientConnPoolIdleCloser = noDialClientConnPool{}
+)
+
+// TODO: use singleflight for dialing and addConnCalls?
+type clientConnPool struct {
+ t *Transport
+
+ mu sync.Mutex // TODO: maybe switch to RWMutex
+ // TODO: add support for sharing conns based on cert names
+ // (e.g. share conn for googleapis.com and appspot.com)
+ conns map[string][]*ClientConn // key is host:port
+ dialing map[string]*dialCall // currently in-flight dials
+ keys map[*ClientConn][]string
+ addConnCalls map[string]*addConnCall // in-flight addConnIfNeede calls
+}
+
+func (p *clientConnPool) GetClientConn(req *http.Request, addr string) (*ClientConn, error) {
+ return p.getClientConn(req, addr, dialOnMiss)
+}
+
+const (
+ dialOnMiss = true
+ noDialOnMiss = false
+)
+
+// shouldTraceGetConn reports whether getClientConn should call any
+// ClientTrace.GetConn hook associated with the http.Request.
+//
+// This complexity is needed to avoid double calls of the GetConn hook
+// during the back-and-forth between net/http and x/net/http2 (when the
+// net/http.Transport is upgraded to also speak http2), as well as support
+// the case where x/net/http2 is being used directly.
+func (p *clientConnPool) shouldTraceGetConn(st clientConnIdleState) bool {
+ // If our Transport wasn't made via ConfigureTransport, always
+ // trace the GetConn hook if provided, because that means the
+ // http2 package is being used directly and it's the one
+ // dialing, as opposed to net/http.
+ if _, ok := p.t.ConnPool.(noDialClientConnPool); !ok {
+ return true
+ }
+ // Otherwise, only use the GetConn hook if this connection has
+ // been used previously for other requests. For fresh
+ // connections, the net/http package does the dialing.
+ return !st.freshConn
+}
+
+func (p *clientConnPool) getClientConn(req *http.Request, addr string, dialOnMiss bool) (*ClientConn, error) {
+ if isConnectionCloseRequest(req) && dialOnMiss {
+ // It gets its own connection.
+ traceGetConn(req, addr)
+ const singleUse = true
+ cc, err := p.t.dialClientConn(req.Context(), addr, singleUse)
+ if err != nil {
+ return nil, err
+ }
+ return cc, nil
+ }
+ for {
+ p.mu.Lock()
+ for _, cc := range p.conns[addr] {
+ if st := cc.idleState(); st.canTakeNewRequest {
+ if p.shouldTraceGetConn(st) {
+ traceGetConn(req, addr)
+ }
+ p.mu.Unlock()
+ return cc, nil
+ }
+ }
+ if !dialOnMiss {
+ p.mu.Unlock()
+ return nil, ErrNoCachedConn
+ }
+ traceGetConn(req, addr)
+ call := p.getStartDialLocked(req.Context(), addr)
+ p.mu.Unlock()
+ <-call.done
+ if shouldRetryDial(call, req) {
+ continue
+ }
+ return call.res, call.err
+ }
+}
+
+// dialCall is an in-flight Transport dial call to a host.
+type dialCall struct {
+ _ incomparable
+ p *clientConnPool
+ // the context associated with the request
+ // that created this dialCall
+ ctx context.Context
+ done chan struct{} // closed when done
+ res *ClientConn // valid after done is closed
+ err error // valid after done is closed
+}
+
+// requires p.mu is held.
+func (p *clientConnPool) getStartDialLocked(ctx context.Context, addr string) *dialCall {
+ if call, ok := p.dialing[addr]; ok {
+ // A dial is already in-flight. Don't start another.
+ return call
+ }
+ call := &dialCall{p: p, done: make(chan struct{}), ctx: ctx}
+ if p.dialing == nil {
+ p.dialing = make(map[string]*dialCall)
+ }
+ p.dialing[addr] = call
+ go call.dial(call.ctx, addr)
+ return call
+}
+
+// run in its own goroutine.
+func (c *dialCall) dial(ctx context.Context, addr string) {
+ const singleUse = false // shared conn
+ c.res, c.err = c.p.t.dialClientConn(ctx, addr, singleUse)
+ close(c.done)
+
+ c.p.mu.Lock()
+ delete(c.p.dialing, addr)
+ if c.err == nil {
+ c.p.addConnLocked(addr, c.res)
+ }
+ c.p.mu.Unlock()
+}
+
+// addConnIfNeeded makes a NewClientConn out of c if a connection for key doesn't
+// already exist. It coalesces concurrent calls with the same key.
+// This is used by the http1 Transport code when it creates a new connection. Because
+// the http1 Transport doesn't de-dup TCP dials to outbound hosts (because it doesn't know
+// the protocol), it can get into a situation where it has multiple TLS connections.
+// This code decides which ones live or die.
+// The return value used is whether c was used.
+// c is never closed.
+func (p *clientConnPool) addConnIfNeeded(key string, t *Transport, c *tls.Conn) (used bool, err error) {
+ p.mu.Lock()
+ for _, cc := range p.conns[key] {
+ if cc.CanTakeNewRequest() {
+ p.mu.Unlock()
+ return false, nil
+ }
+ }
+ call, dup := p.addConnCalls[key]
+ if !dup {
+ if p.addConnCalls == nil {
+ p.addConnCalls = make(map[string]*addConnCall)
+ }
+ call = &addConnCall{
+ p: p,
+ done: make(chan struct{}),
+ }
+ p.addConnCalls[key] = call
+ go call.run(t, key, c)
+ }
+ p.mu.Unlock()
+
+ <-call.done
+ if call.err != nil {
+ return false, call.err
+ }
+ return !dup, nil
+}
+
+type addConnCall struct {
+ _ incomparable
+ p *clientConnPool
+ done chan struct{} // closed when done
+ err error
+}
+
+func (c *addConnCall) run(t *Transport, key string, tc *tls.Conn) {
+ cc, err := t.NewClientConn(tc)
+
+ p := c.p
+ p.mu.Lock()
+ if err != nil {
+ c.err = err
+ } else {
+ p.addConnLocked(key, cc)
+ }
+ delete(p.addConnCalls, key)
+ p.mu.Unlock()
+ close(c.done)
+}
+
+// p.mu must be held
+func (p *clientConnPool) addConnLocked(key string, cc *ClientConn) {
+ for _, v := range p.conns[key] {
+ if v == cc {
+ return
+ }
+ }
+ if p.conns == nil {
+ p.conns = make(map[string][]*ClientConn)
+ }
+ if p.keys == nil {
+ p.keys = make(map[*ClientConn][]string)
+ }
+ p.conns[key] = append(p.conns[key], cc)
+ p.keys[cc] = append(p.keys[cc], key)
+}
+
+func (p *clientConnPool) MarkDead(cc *ClientConn) {
+ p.mu.Lock()
+ defer p.mu.Unlock()
+ for _, key := range p.keys[cc] {
+ vv, ok := p.conns[key]
+ if !ok {
+ continue
+ }
+ newList := filterOutClientConn(vv, cc)
+ if len(newList) > 0 {
+ p.conns[key] = newList
+ } else {
+ delete(p.conns, key)
+ }
+ }
+ delete(p.keys, cc)
+}
+
+func (p *clientConnPool) closeIdleConnections() {
+ p.mu.Lock()
+ defer p.mu.Unlock()
+ // TODO: don't close a cc if it was just added to the pool
+ // milliseconds ago and has never been used. There's currently
+ // a small race window with the HTTP/1 Transport's integration
+ // where it can add an idle conn just before using it, and
+ // somebody else can concurrently call CloseIdleConns and
+ // break some caller's RoundTrip.
+ for _, vv := range p.conns {
+ for _, cc := range vv {
+ cc.closeIfIdle()
+ }
+ }
+}
+
+func filterOutClientConn(in []*ClientConn, exclude *ClientConn) []*ClientConn {
+ out := in[:0]
+ for _, v := range in {
+ if v != exclude {
+ out = append(out, v)
+ }
+ }
+ // If we filtered it out, zero out the last item to prevent
+ // the GC from seeing it.
+ if len(in) != len(out) {
+ in[len(in)-1] = nil
+ }
+ return out
+}
+
+// noDialClientConnPool is an implementation of http2.ClientConnPool
+// which never dials. We let the HTTP/1.1 client dial and use its TLS
+// connection instead.
+type noDialClientConnPool struct{ *clientConnPool }
+
+func (p noDialClientConnPool) GetClientConn(req *http.Request, addr string) (*ClientConn, error) {
+ return p.getClientConn(req, addr, noDialOnMiss)
+}
+
+// shouldRetryDial reports whether the current request should
+// retry dialing after the call finished unsuccessfully, for example
+// if the dial was canceled because of a context cancellation or
+// deadline expiry.
+func shouldRetryDial(call *dialCall, req *http.Request) bool {
+ if call.err == nil {
+ // No error, no need to retry
+ return false
+ }
+ if call.ctx == req.Context() {
+ // If the call has the same context as the request, the dial
+ // should not be retried, since any cancellation will have come
+ // from this request.
+ return false
+ }
+ if !errors.Is(call.err, context.Canceled) && !errors.Is(call.err, context.DeadlineExceeded) {
+ // If the call error is not because of a context cancellation or a deadline expiry,
+ // the dial should not be retried.
+ return false
+ }
+ // Only retry if the error is a context cancellation error or deadline expiry
+ // and the context associated with the call was canceled or expired.
+ return call.ctx.Err() != nil
+}