chore: vendor

vendor/google.golang.org/grpc/internal/channelz/channel.go

@@ -0,0 +1,255 @@
+/*
+ *
+ * Copyright 2024 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package channelz
+
+import (
+	"fmt"
+	"sync/atomic"
+
+	"google.golang.org/grpc/connectivity"
+)
+
+// Channel represents a channel within channelz, which includes metrics and
+// internal channelz data, such as channelz id, child list, etc.
+type Channel struct {
+	Entity
+	// ID is the channelz id of this channel.
+	ID int64
+	// RefName is the human readable reference string of this channel.
+	RefName string
+
+	closeCalled bool
+	nestedChans map[int64]string
+	subChans    map[int64]string
+	Parent      *Channel
+	trace       *ChannelTrace
+	// traceRefCount is the number of trace events that reference this channel.
+	// Non-zero traceRefCount means the trace of this channel cannot be deleted.
+	traceRefCount int32
+
+	ChannelMetrics ChannelMetrics
+}
+
+// Implemented to make Channel implement the Identifier interface used for
+// nesting.
+func (c *Channel) channelzIdentifier() {}
+
+func (c *Channel) String() string {
+	if c.Parent == nil {
+		return fmt.Sprintf("Channel #%d", c.ID)
+	}
+	return fmt.Sprintf("%s Channel #%d", c.Parent, c.ID)
+}
+
+func (c *Channel) id() int64 {
+	return c.ID
+}
+
+func (c *Channel) SubChans() map[int64]string {
+	db.mu.RLock()
+	defer db.mu.RUnlock()
+	return copyMap(c.subChans)
+}
+
+func (c *Channel) NestedChans() map[int64]string {
+	db.mu.RLock()
+	defer db.mu.RUnlock()
+	return copyMap(c.nestedChans)
+}
+
+func (c *Channel) Trace() *ChannelTrace {
+	db.mu.RLock()
+	defer db.mu.RUnlock()
+	return c.trace.copy()
+}
+
+type ChannelMetrics struct {
+	// The current connectivity state of the channel.
+	State atomic.Pointer[connectivity.State]
+	// The target this channel originally tried to connect to.  May be absent
+	Target atomic.Pointer[string]
+	// The number of calls started on the channel.
+	CallsStarted atomic.Int64
+	// The number of calls that have completed with an OK status.
+	CallsSucceeded atomic.Int64
+	// The number of calls that have a completed with a non-OK status.
+	CallsFailed atomic.Int64
+	// The last time a call was started on the channel.
+	LastCallStartedTimestamp atomic.Int64
+}
+
+// CopyFrom copies the metrics in o to c.  For testing only.
+func (c *ChannelMetrics) CopyFrom(o *ChannelMetrics) {
+	c.State.Store(o.State.Load())
+	c.Target.Store(o.Target.Load())
+	c.CallsStarted.Store(o.CallsStarted.Load())
+	c.CallsSucceeded.Store(o.CallsSucceeded.Load())
+	c.CallsFailed.Store(o.CallsFailed.Load())
+	c.LastCallStartedTimestamp.Store(o.LastCallStartedTimestamp.Load())
+}
+
+// Equal returns true iff the metrics of c are the same as the metrics of o.
+// For testing only.
+func (c *ChannelMetrics) Equal(o any) bool {
+	oc, ok := o.(*ChannelMetrics)
+	if !ok {
+		return false
+	}
+	if (c.State.Load() == nil) != (oc.State.Load() == nil) {
+		return false
+	}
+	if c.State.Load() != nil && *c.State.Load() != *oc.State.Load() {
+		return false
+	}
+	if (c.Target.Load() == nil) != (oc.Target.Load() == nil) {
+		return false
+	}
+	if c.Target.Load() != nil && *c.Target.Load() != *oc.Target.Load() {
+		return false
+	}
+	return c.CallsStarted.Load() == oc.CallsStarted.Load() &&
+		c.CallsFailed.Load() == oc.CallsFailed.Load() &&
+		c.CallsSucceeded.Load() == oc.CallsSucceeded.Load() &&
+		c.LastCallStartedTimestamp.Load() == oc.LastCallStartedTimestamp.Load()
+}
+
+func strFromPointer(s *string) string {
+	if s == nil {
+		return ""
+	}
+	return *s
+}
+
+func (c *ChannelMetrics) String() string {
+	return fmt.Sprintf("State: %v, Target: %s, CallsStarted: %v, CallsSucceeded: %v, CallsFailed: %v, LastCallStartedTimestamp: %v",
+		c.State.Load(), strFromPointer(c.Target.Load()), c.CallsStarted.Load(), c.CallsSucceeded.Load(), c.CallsFailed.Load(), c.LastCallStartedTimestamp.Load(),
+	)
+}
+
+func NewChannelMetricForTesting(state connectivity.State, target string, started, succeeded, failed, timestamp int64) *ChannelMetrics {
+	c := &ChannelMetrics{}
+	c.State.Store(&state)
+	c.Target.Store(&target)
+	c.CallsStarted.Store(started)
+	c.CallsSucceeded.Store(succeeded)
+	c.CallsFailed.Store(failed)
+	c.LastCallStartedTimestamp.Store(timestamp)
+	return c
+}
+
+func (c *Channel) addChild(id int64, e entry) {
+	switch v := e.(type) {
+	case *SubChannel:
+		c.subChans[id] = v.RefName
+	case *Channel:
+		c.nestedChans[id] = v.RefName
+	default:
+		logger.Errorf("cannot add a child (id = %d) of type %T to a channel", id, e)
+	}
+}
+
+func (c *Channel) deleteChild(id int64) {
+	delete(c.subChans, id)
+	delete(c.nestedChans, id)
+	c.deleteSelfIfReady()
+}
+
+func (c *Channel) triggerDelete() {
+	c.closeCalled = true
+	c.deleteSelfIfReady()
+}
+
+func (c *Channel) getParentID() int64 {
+	if c.Parent == nil {
+		return -1
+	}
+	return c.Parent.ID
+}
+
+// deleteSelfFromTree tries to delete the channel from the channelz entry relation tree, which means
+// deleting the channel reference from its parent's child list.
+//
+// In order for a channel to be deleted from the tree, it must meet the criteria that, removal of the
+// corresponding grpc object has been invoked, and the channel does not have any children left.
+//
+// The returned boolean value indicates whether the channel has been successfully deleted from tree.
+func (c *Channel) deleteSelfFromTree() (deleted bool) {
+	if !c.closeCalled || len(c.subChans)+len(c.nestedChans) != 0 {
+		return false
+	}
+	// not top channel
+	if c.Parent != nil {
+		c.Parent.deleteChild(c.ID)
+	}
+	return true
+}
+
+// deleteSelfFromMap checks whether it is valid to delete the channel from the map, which means
+// deleting the channel from channelz's tracking entirely. Users can no longer use id to query the
+// channel, and its memory will be garbage collected.
+//
+// The trace reference count of the channel must be 0 in order to be deleted from the map. This is
+// specified in the channel tracing gRFC that as long as some other trace has reference to an entity,
+// the trace of the referenced entity must not be deleted. In order to release the resource allocated
+// by grpc, the reference to the grpc object is reset to a dummy object.
+//
+// deleteSelfFromMap must be called after deleteSelfFromTree returns true.
+//
+// It returns a bool to indicate whether the channel can be safely deleted from map.
+func (c *Channel) deleteSelfFromMap() (delete bool) {
+	return c.getTraceRefCount() == 0
+}
+
+// deleteSelfIfReady tries to delete the channel itself from the channelz database.
+// The delete process includes two steps:
+//  1. delete the channel from the entry relation tree, i.e. delete the channel reference from its
+//     parent's child list.
+//  2. delete the channel from the map, i.e. delete the channel entirely from channelz. Lookup by id
+//     will return entry not found error.
+func (c *Channel) deleteSelfIfReady() {
+	if !c.deleteSelfFromTree() {
+		return
+	}
+	if !c.deleteSelfFromMap() {
+		return
+	}
+	db.deleteEntry(c.ID)
+	c.trace.clear()
+}
+
+func (c *Channel) getChannelTrace() *ChannelTrace {
+	return c.trace
+}
+
+func (c *Channel) incrTraceRefCount() {
+	atomic.AddInt32(&c.traceRefCount, 1)
+}
+
+func (c *Channel) decrTraceRefCount() {
+	atomic.AddInt32(&c.traceRefCount, -1)
+}
+
+func (c *Channel) getTraceRefCount() int {
+	i := atomic.LoadInt32(&c.traceRefCount)
+	return int(i)
+}
+
+func (c *Channel) getRefName() string {
+	return c.RefName
+}

vendor/google.golang.org/grpc/internal/channelz/channelmap.go

@@ -0,0 +1,402 @@
+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package channelz
+
+import (
+	"fmt"
+	"sort"
+	"sync"
+	"time"
+)
+
+// entry represents a node in the channelz database.
+type entry interface {
+	// addChild adds a child e, whose channelz id is id to child list
+	addChild(id int64, e entry)
+	// deleteChild deletes a child with channelz id to be id from child list
+	deleteChild(id int64)
+	// triggerDelete tries to delete self from channelz database. However, if
+	// child list is not empty, then deletion from the database is on hold until
+	// the last child is deleted from database.
+	triggerDelete()
+	// deleteSelfIfReady check whether triggerDelete() has been called before,
+	// and whether child list is now empty. If both conditions are met, then
+	// delete self from database.
+	deleteSelfIfReady()
+	// getParentID returns parent ID of the entry. 0 value parent ID means no parent.
+	getParentID() int64
+	Entity
+}
+
+// channelMap is the storage data structure for channelz.
+//
+// Methods of channelMap can be divided in two two categories with respect to
+// locking.
+//
+// 1. Methods acquire the global lock.
+// 2. Methods that can only be called when global lock is held.
+//
+// A second type of method need always to be called inside a first type of method.
+type channelMap struct {
+	mu               sync.RWMutex
+	topLevelChannels map[int64]struct{}
+	channels         map[int64]*Channel
+	subChannels      map[int64]*SubChannel
+	sockets          map[int64]*Socket
+	servers          map[int64]*Server
+}
+
+func newChannelMap() *channelMap {
+	return &channelMap{
+		topLevelChannels: make(map[int64]struct{}),
+		channels:         make(map[int64]*Channel),
+		subChannels:      make(map[int64]*SubChannel),
+		sockets:          make(map[int64]*Socket),
+		servers:          make(map[int64]*Server),
+	}
+}
+
+func (c *channelMap) addServer(id int64, s *Server) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	s.cm = c
+	c.servers[id] = s
+}
+
+func (c *channelMap) addChannel(id int64, cn *Channel, isTopChannel bool, pid int64) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	cn.trace.cm = c
+	c.channels[id] = cn
+	if isTopChannel {
+		c.topLevelChannels[id] = struct{}{}
+	} else if p := c.channels[pid]; p != nil {
+		p.addChild(id, cn)
+	} else {
+		logger.Infof("channel %d references invalid parent ID %d", id, pid)
+	}
+}
+
+func (c *channelMap) addSubChannel(id int64, sc *SubChannel, pid int64) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	sc.trace.cm = c
+	c.subChannels[id] = sc
+	if p := c.channels[pid]; p != nil {
+		p.addChild(id, sc)
+	} else {
+		logger.Infof("subchannel %d references invalid parent ID %d", id, pid)
+	}
+}
+
+func (c *channelMap) addSocket(s *Socket) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	s.cm = c
+	c.sockets[s.ID] = s
+	if s.Parent == nil {
+		logger.Infof("normal socket %d has no parent", s.ID)
+	}
+	s.Parent.(entry).addChild(s.ID, s)
+}
+
+// removeEntry triggers the removal of an entry, which may not indeed delete the
+// entry, if it has to wait on the deletion of its children and until no other
+// entity's channel trace references it.  It may lead to a chain of entry
+// deletion. For example, deleting the last socket of a gracefully shutting down
+// server will lead to the server being also deleted.
+func (c *channelMap) removeEntry(id int64) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	c.findEntry(id).triggerDelete()
+}
+
+// tracedChannel represents tracing operations which are present on both
+// channels and subChannels.
+type tracedChannel interface {
+	getChannelTrace() *ChannelTrace
+	incrTraceRefCount()
+	decrTraceRefCount()
+	getRefName() string
+}
+
+// c.mu must be held by the caller
+func (c *channelMap) decrTraceRefCount(id int64) {
+	e := c.findEntry(id)
+	if v, ok := e.(tracedChannel); ok {
+		v.decrTraceRefCount()
+		e.deleteSelfIfReady()
+	}
+}
+
+// c.mu must be held by the caller.
+func (c *channelMap) findEntry(id int64) entry {
+	if v, ok := c.channels[id]; ok {
+		return v
+	}
+	if v, ok := c.subChannels[id]; ok {
+		return v
+	}
+	if v, ok := c.servers[id]; ok {
+		return v
+	}
+	if v, ok := c.sockets[id]; ok {
+		return v
+	}
+	return &dummyEntry{idNotFound: id}
+}
+
+// c.mu must be held by the caller
+//
+// deleteEntry deletes an entry from the channelMap. Before calling this method,
+// caller must check this entry is ready to be deleted, i.e removeEntry() has
+// been called on it, and no children still exist.
+func (c *channelMap) deleteEntry(id int64) entry {
+	if v, ok := c.sockets[id]; ok {
+		delete(c.sockets, id)
+		return v
+	}
+	if v, ok := c.subChannels[id]; ok {
+		delete(c.subChannels, id)
+		return v
+	}
+	if v, ok := c.channels[id]; ok {
+		delete(c.channels, id)
+		delete(c.topLevelChannels, id)
+		return v
+	}
+	if v, ok := c.servers[id]; ok {
+		delete(c.servers, id)
+		return v
+	}
+	return &dummyEntry{idNotFound: id}
+}
+
+func (c *channelMap) traceEvent(id int64, desc *TraceEvent) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	child := c.findEntry(id)
+	childTC, ok := child.(tracedChannel)
+	if !ok {
+		return
+	}
+	childTC.getChannelTrace().append(&traceEvent{Desc: desc.Desc, Severity: desc.Severity, Timestamp: time.Now()})
+	if desc.Parent != nil {
+		parent := c.findEntry(child.getParentID())
+		var chanType RefChannelType
+		switch child.(type) {
+		case *Channel:
+			chanType = RefChannel
+		case *SubChannel:
+			chanType = RefSubChannel
+		}
+		if parentTC, ok := parent.(tracedChannel); ok {
+			parentTC.getChannelTrace().append(&traceEvent{
+				Desc:      desc.Parent.Desc,
+				Severity:  desc.Parent.Severity,
+				Timestamp: time.Now(),
+				RefID:     id,
+				RefName:   childTC.getRefName(),
+				RefType:   chanType,
+			})
+			childTC.incrTraceRefCount()
+		}
+	}
+}
+
+type int64Slice []int64
+
+func (s int64Slice) Len() int           { return len(s) }
+func (s int64Slice) Swap(i, j int)      { s[i], s[j] = s[j], s[i] }
+func (s int64Slice) Less(i, j int) bool { return s[i] < s[j] }
+
+func copyMap(m map[int64]string) map[int64]string {
+	n := make(map[int64]string)
+	for k, v := range m {
+		n[k] = v
+	}
+	return n
+}
+
+func min(a, b int) int {
+	if a < b {
+		return a
+	}
+	return b
+}
+
+func (c *channelMap) getTopChannels(id int64, maxResults int) ([]*Channel, bool) {
+	if maxResults <= 0 {
+		maxResults = EntriesPerPage
+	}
+	c.mu.RLock()
+	defer c.mu.RUnlock()
+	l := int64(len(c.topLevelChannels))
+	ids := make([]int64, 0, l)
+
+	for k := range c.topLevelChannels {
+		ids = append(ids, k)
+	}
+	sort.Sort(int64Slice(ids))
+	idx := sort.Search(len(ids), func(i int) bool { return ids[i] >= id })
+	end := true
+	var t []*Channel
+	for _, v := range ids[idx:] {
+		if len(t) == maxResults {
+			end = false
+			break
+		}
+		if cn, ok := c.channels[v]; ok {
+			t = append(t, cn)
+		}
+	}
+	return t, end
+}
+
+func (c *channelMap) getServers(id int64, maxResults int) ([]*Server, bool) {
+	if maxResults <= 0 {
+		maxResults = EntriesPerPage
+	}
+	c.mu.RLock()
+	defer c.mu.RUnlock()
+	ids := make([]int64, 0, len(c.servers))
+	for k := range c.servers {
+		ids = append(ids, k)
+	}
+	sort.Sort(int64Slice(ids))
+	idx := sort.Search(len(ids), func(i int) bool { return ids[i] >= id })
+	end := true
+	var s []*Server
+	for _, v := range ids[idx:] {
+		if len(s) == maxResults {
+			end = false
+			break
+		}
+		if svr, ok := c.servers[v]; ok {
+			s = append(s, svr)
+		}
+	}
+	return s, end
+}
+
+func (c *channelMap) getServerSockets(id int64, startID int64, maxResults int) ([]*Socket, bool) {
+	if maxResults <= 0 {
+		maxResults = EntriesPerPage
+	}
+	c.mu.RLock()
+	defer c.mu.RUnlock()
+	svr, ok := c.servers[id]
+	if !ok {
+		// server with id doesn't exist.
+		return nil, true
+	}
+	svrskts := svr.sockets
+	ids := make([]int64, 0, len(svrskts))
+	sks := make([]*Socket, 0, min(len(svrskts), maxResults))
+	for k := range svrskts {
+		ids = append(ids, k)
+	}
+	sort.Sort(int64Slice(ids))
+	idx := sort.Search(len(ids), func(i int) bool { return ids[i] >= startID })
+	end := true
+	for _, v := range ids[idx:] {
+		if len(sks) == maxResults {
+			end = false
+			break
+		}
+		if ns, ok := c.sockets[v]; ok {
+			sks = append(sks, ns)
+		}
+	}
+	return sks, end
+}
+
+func (c *channelMap) getChannel(id int64) *Channel {
+	c.mu.RLock()
+	defer c.mu.RUnlock()
+	return c.channels[id]
+}
+
+func (c *channelMap) getSubChannel(id int64) *SubChannel {
+	c.mu.RLock()
+	defer c.mu.RUnlock()
+	return c.subChannels[id]
+}
+
+func (c *channelMap) getSocket(id int64) *Socket {
+	c.mu.RLock()
+	defer c.mu.RUnlock()
+	return c.sockets[id]
+}
+
+func (c *channelMap) getServer(id int64) *Server {
+	c.mu.RLock()
+	defer c.mu.RUnlock()
+	return c.servers[id]
+}
+
+type dummyEntry struct {
+	// dummyEntry is a fake entry to handle entry not found case.
+	idNotFound int64
+	Entity
+}
+
+func (d *dummyEntry) String() string {
+	return fmt.Sprintf("non-existent entity #%d", d.idNotFound)
+}
+
+func (d *dummyEntry) ID() int64 { return d.idNotFound }
+
+func (d *dummyEntry) addChild(id int64, e entry) {
+	// Note: It is possible for a normal program to reach here under race
+	// condition.  For example, there could be a race between ClientConn.Close()
+	// info being propagated to addrConn and http2Client. ClientConn.Close()
+	// cancel the context and result in http2Client to error. The error info is
+	// then caught by transport monitor and before addrConn.tearDown() is called
+	// in side ClientConn.Close(). Therefore, the addrConn will create a new
+	// transport. And when registering the new transport in channelz, its parent
+	// addrConn could have already been torn down and deleted from channelz
+	// tracking, and thus reach the code here.
+	logger.Infof("attempt to add child of type %T with id %d to a parent (id=%d) that doesn't currently exist", e, id, d.idNotFound)
+}
+
+func (d *dummyEntry) deleteChild(id int64) {
+	// It is possible for a normal program to reach here under race condition.
+	// Refer to the example described in addChild().
+	logger.Infof("attempt to delete child with id %d from a parent (id=%d) that doesn't currently exist", id, d.idNotFound)
+}
+
+func (d *dummyEntry) triggerDelete() {
+	logger.Warningf("attempt to delete an entry (id=%d) that doesn't currently exist", d.idNotFound)
+}
+
+func (*dummyEntry) deleteSelfIfReady() {
+	// code should not reach here. deleteSelfIfReady is always called on an existing entry.
+}
+
+func (*dummyEntry) getParentID() int64 {
+	return 0
+}
+
+// Entity is implemented by all channelz types.
+type Entity interface {
+	isEntity()
+	fmt.Stringer
+	id() int64
+}

vendor/google.golang.org/grpc/internal/channelz/funcs.go

@@ -0,0 +1,230 @@
+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+// Package channelz defines internal APIs for enabling channelz service, entry
+// registration/deletion, and accessing channelz data. It also defines channelz
+// metric struct formats.
+package channelz
+
+import (
+	"sync/atomic"
+	"time"
+
+	"google.golang.org/grpc/internal"
+)
+
+var (
+	// IDGen is the global channelz entity ID generator.  It should not be used
+	// outside this package except by tests.
+	IDGen IDGenerator
+
+	db *channelMap = newChannelMap()
+	// EntriesPerPage defines the number of channelz entries to be shown on a web page.
+	EntriesPerPage = 50
+	curState       int32
+)
+
+// TurnOn turns on channelz data collection.
+func TurnOn() {
+	atomic.StoreInt32(&curState, 1)
+}
+
+func init() {
+	internal.ChannelzTurnOffForTesting = func() {
+		atomic.StoreInt32(&curState, 0)
+	}
+}
+
+// IsOn returns whether channelz data collection is on.
+func IsOn() bool {
+	return atomic.LoadInt32(&curState) == 1
+}
+
+// GetTopChannels returns a slice of top channel's ChannelMetric, along with a
+// boolean indicating whether there's more top channels to be queried for.
+//
+// The arg id specifies that only top channel with id at or above it will be
+// included in the result. The returned slice is up to a length of the arg
+// maxResults or EntriesPerPage if maxResults is zero, and is sorted in ascending
+// id order.
+func GetTopChannels(id int64, maxResults int) ([]*Channel, bool) {
+	return db.getTopChannels(id, maxResults)
+}
+
+// GetServers returns a slice of server's ServerMetric, along with a
+// boolean indicating whether there's more servers to be queried for.
+//
+// The arg id specifies that only server with id at or above it will be included
+// in the result. The returned slice is up to a length of the arg maxResults or
+// EntriesPerPage if maxResults is zero, and is sorted in ascending id order.
+func GetServers(id int64, maxResults int) ([]*Server, bool) {
+	return db.getServers(id, maxResults)
+}
+
+// GetServerSockets returns a slice of server's (identified by id) normal socket's
+// SocketMetrics, along with a boolean indicating whether there's more sockets to
+// be queried for.
+//
+// The arg startID specifies that only sockets with id at or above it will be
+// included in the result. The returned slice is up to a length of the arg maxResults
+// or EntriesPerPage if maxResults is zero, and is sorted in ascending id order.
+func GetServerSockets(id int64, startID int64, maxResults int) ([]*Socket, bool) {
+	return db.getServerSockets(id, startID, maxResults)
+}
+
+// GetChannel returns the Channel for the channel (identified by id).
+func GetChannel(id int64) *Channel {
+	return db.getChannel(id)
+}
+
+// GetSubChannel returns the SubChannel for the subchannel (identified by id).
+func GetSubChannel(id int64) *SubChannel {
+	return db.getSubChannel(id)
+}
+
+// GetSocket returns the Socket for the socket (identified by id).
+func GetSocket(id int64) *Socket {
+	return db.getSocket(id)
+}
+
+// GetServer returns the ServerMetric for the server (identified by id).
+func GetServer(id int64) *Server {
+	return db.getServer(id)
+}
+
+// RegisterChannel registers the given channel c in the channelz database with
+// target as its target and reference name, and adds it to the child list of its
+// parent.  parent == nil means no parent.
+//
+// Returns a unique channelz identifier assigned to this channel.
+//
+// If channelz is not turned ON, the channelz database is not mutated.
+func RegisterChannel(parent *Channel, target string) *Channel {
+	id := IDGen.genID()
+
+	if !IsOn() {
+		return &Channel{ID: id}
+	}
+
+	isTopChannel := parent == nil
+
+	cn := &Channel{
+		ID:          id,
+		RefName:     target,
+		nestedChans: make(map[int64]string),
+		subChans:    make(map[int64]string),
+		Parent:      parent,
+		trace:       &ChannelTrace{CreationTime: time.Now(), Events: make([]*traceEvent, 0, getMaxTraceEntry())},
+	}
+	cn.ChannelMetrics.Target.Store(&target)
+	db.addChannel(id, cn, isTopChannel, cn.getParentID())
+	return cn
+}
+
+// RegisterSubChannel registers the given subChannel c in the channelz database
+// with ref as its reference name, and adds it to the child list of its parent
+// (identified by pid).
+//
+// Returns a unique channelz identifier assigned to this subChannel.
+//
+// If channelz is not turned ON, the channelz database is not mutated.
+func RegisterSubChannel(parent *Channel, ref string) *SubChannel {
+	id := IDGen.genID()
+	sc := &SubChannel{
+		ID:      id,
+		RefName: ref,
+		parent:  parent,
+	}
+
+	if !IsOn() {
+		return sc
+	}
+
+	sc.sockets = make(map[int64]string)
+	sc.trace = &ChannelTrace{CreationTime: time.Now(), Events: make([]*traceEvent, 0, getMaxTraceEntry())}
+	db.addSubChannel(id, sc, parent.ID)
+	return sc
+}
+
+// RegisterServer registers the given server s in channelz database. It returns
+// the unique channelz tracking id assigned to this server.
+//
+// If channelz is not turned ON, the channelz database is not mutated.
+func RegisterServer(ref string) *Server {
+	id := IDGen.genID()
+	if !IsOn() {
+		return &Server{ID: id}
+	}
+
+	svr := &Server{
+		RefName:       ref,
+		sockets:       make(map[int64]string),
+		listenSockets: make(map[int64]string),
+		ID:            id,
+	}
+	db.addServer(id, svr)
+	return svr
+}
+
+// RegisterSocket registers the given normal socket s in channelz database
+// with ref as its reference name, and adds it to the child list of its parent
+// (identified by skt.Parent, which must be set). It returns the unique channelz
+// tracking id assigned to this normal socket.
+//
+// If channelz is not turned ON, the channelz database is not mutated.
+func RegisterSocket(skt *Socket) *Socket {
+	skt.ID = IDGen.genID()
+	if IsOn() {
+		db.addSocket(skt)
+	}
+	return skt
+}
+
+// RemoveEntry removes an entry with unique channelz tracking id to be id from
+// channelz database.
+//
+// If channelz is not turned ON, this function is a no-op.
+func RemoveEntry(id int64) {
+	if !IsOn() {
+		return
+	}
+	db.removeEntry(id)
+}
+
+// IDGenerator is an incrementing atomic that tracks IDs for channelz entities.
+type IDGenerator struct {
+	id int64
+}
+
+// Reset resets the generated ID back to zero.  Should only be used at
+// initialization or by tests sensitive to the ID number.
+func (i *IDGenerator) Reset() {
+	atomic.StoreInt64(&i.id, 0)
+}
+
+func (i *IDGenerator) genID() int64 {
+	return atomic.AddInt64(&i.id, 1)
+}
+
+// Identifier is an opaque channelz identifier used to expose channelz symbols
+// outside of grpc.  Currently only implemented by Channel since no other
+// types require exposure outside grpc.
+type Identifier interface {
+	Entity
+	channelzIdentifier()
+}

vendor/google.golang.org/grpc/internal/channelz/logging.go

@@ -0,0 +1,75 @@
+/*
+ *
+ * Copyright 2020 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package channelz
+
+import (
+	"fmt"
+
+	"google.golang.org/grpc/grpclog"
+)
+
+var logger = grpclog.Component("channelz")
+
+// Info logs and adds a trace event if channelz is on.
+func Info(l grpclog.DepthLoggerV2, e Entity, args ...any) {
+	AddTraceEvent(l, e, 1, &TraceEvent{
+		Desc:     fmt.Sprint(args...),
+		Severity: CtInfo,
+	})
+}
+
+// Infof logs and adds a trace event if channelz is on.
+func Infof(l grpclog.DepthLoggerV2, e Entity, format string, args ...any) {
+	AddTraceEvent(l, e, 1, &TraceEvent{
+		Desc:     fmt.Sprintf(format, args...),
+		Severity: CtInfo,
+	})
+}
+
+// Warning logs and adds a trace event if channelz is on.
+func Warning(l grpclog.DepthLoggerV2, e Entity, args ...any) {
+	AddTraceEvent(l, e, 1, &TraceEvent{
+		Desc:     fmt.Sprint(args...),
+		Severity: CtWarning,
+	})
+}
+
+// Warningf logs and adds a trace event if channelz is on.
+func Warningf(l grpclog.DepthLoggerV2, e Entity, format string, args ...any) {
+	AddTraceEvent(l, e, 1, &TraceEvent{
+		Desc:     fmt.Sprintf(format, args...),
+		Severity: CtWarning,
+	})
+}
+
+// Error logs and adds a trace event if channelz is on.
+func Error(l grpclog.DepthLoggerV2, e Entity, args ...any) {
+	AddTraceEvent(l, e, 1, &TraceEvent{
+		Desc:     fmt.Sprint(args...),
+		Severity: CtError,
+	})
+}
+
+// Errorf logs and adds a trace event if channelz is on.
+func Errorf(l grpclog.DepthLoggerV2, e Entity, format string, args ...any) {
+	AddTraceEvent(l, e, 1, &TraceEvent{
+		Desc:     fmt.Sprintf(format, args...),
+		Severity: CtError,
+	})
+}

vendor/google.golang.org/grpc/internal/channelz/server.go

@@ -0,0 +1,119 @@
+/*
+ *
+ * Copyright 2024 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package channelz
+
+import (
+	"fmt"
+	"sync/atomic"
+)
+
+// Server is the channelz representation of a server.
+type Server struct {
+	Entity
+	ID      int64
+	RefName string
+
+	ServerMetrics ServerMetrics
+
+	closeCalled   bool
+	sockets       map[int64]string
+	listenSockets map[int64]string
+	cm            *channelMap
+}
+
+// ServerMetrics defines a struct containing metrics for servers.
+type ServerMetrics struct {
+	// The number of incoming calls started on the server.
+	CallsStarted atomic.Int64
+	// The number of incoming calls that have completed with an OK status.
+	CallsSucceeded atomic.Int64
+	// The number of incoming calls that have a completed with a non-OK status.
+	CallsFailed atomic.Int64
+	// The last time a call was started on the server.
+	LastCallStartedTimestamp atomic.Int64
+}
+
+// NewServerMetricsForTesting returns an initialized ServerMetrics.
+func NewServerMetricsForTesting(started, succeeded, failed, timestamp int64) *ServerMetrics {
+	sm := &ServerMetrics{}
+	sm.CallsStarted.Store(started)
+	sm.CallsSucceeded.Store(succeeded)
+	sm.CallsFailed.Store(failed)
+	sm.LastCallStartedTimestamp.Store(timestamp)
+	return sm
+}
+
+func (sm *ServerMetrics) CopyFrom(o *ServerMetrics) {
+	sm.CallsStarted.Store(o.CallsStarted.Load())
+	sm.CallsSucceeded.Store(o.CallsSucceeded.Load())
+	sm.CallsFailed.Store(o.CallsFailed.Load())
+	sm.LastCallStartedTimestamp.Store(o.LastCallStartedTimestamp.Load())
+}
+
+// ListenSockets returns the listening sockets for s.
+func (s *Server) ListenSockets() map[int64]string {
+	db.mu.RLock()
+	defer db.mu.RUnlock()
+	return copyMap(s.listenSockets)
+}
+
+// String returns a printable description of s.
+func (s *Server) String() string {
+	return fmt.Sprintf("Server #%d", s.ID)
+}
+
+func (s *Server) id() int64 {
+	return s.ID
+}
+
+func (s *Server) addChild(id int64, e entry) {
+	switch v := e.(type) {
+	case *Socket:
+		switch v.SocketType {
+		case SocketTypeNormal:
+			s.sockets[id] = v.RefName
+		case SocketTypeListen:
+			s.listenSockets[id] = v.RefName
+		}
+	default:
+		logger.Errorf("cannot add a child (id = %d) of type %T to a server", id, e)
+	}
+}
+
+func (s *Server) deleteChild(id int64) {
+	delete(s.sockets, id)
+	delete(s.listenSockets, id)
+	s.deleteSelfIfReady()
+}
+
+func (s *Server) triggerDelete() {
+	s.closeCalled = true
+	s.deleteSelfIfReady()
+}
+
+func (s *Server) deleteSelfIfReady() {
+	if !s.closeCalled || len(s.sockets)+len(s.listenSockets) != 0 {
+		return
+	}
+	s.cm.deleteEntry(s.ID)
+}
+
+func (s *Server) getParentID() int64 {
+	return 0
+}

vendor/google.golang.org/grpc/internal/channelz/socket.go

@@ -0,0 +1,130 @@
+/*
+ *
+ * Copyright 2024 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package channelz
+
+import (
+	"fmt"
+	"net"
+	"sync/atomic"
+
+	"google.golang.org/grpc/credentials"
+)
+
+// SocketMetrics defines the struct that the implementor of Socket interface
+// should return from ChannelzMetric().
+type SocketMetrics struct {
+	// The number of streams that have been started.
+	StreamsStarted atomic.Int64
+	// The number of streams that have ended successfully:
+	// On client side, receiving frame with eos bit set.
+	// On server side, sending frame with eos bit set.
+	StreamsSucceeded atomic.Int64
+	// The number of streams that have ended unsuccessfully:
+	// On client side, termination without receiving frame with eos bit set.
+	// On server side, termination without sending frame with eos bit set.
+	StreamsFailed atomic.Int64
+	// The number of messages successfully sent on this socket.
+	MessagesSent     atomic.Int64
+	MessagesReceived atomic.Int64
+	// The number of keep alives sent.  This is typically implemented with HTTP/2
+	// ping messages.
+	KeepAlivesSent atomic.Int64
+	// The last time a stream was created by this endpoint.  Usually unset for
+	// servers.
+	LastLocalStreamCreatedTimestamp atomic.Int64
+	// The last time a stream was created by the remote endpoint.  Usually unset
+	// for clients.
+	LastRemoteStreamCreatedTimestamp atomic.Int64
+	// The last time a message was sent by this endpoint.
+	LastMessageSentTimestamp atomic.Int64
+	// The last time a message was received by this endpoint.
+	LastMessageReceivedTimestamp atomic.Int64
+}
+
+// EphemeralSocketMetrics are metrics that change rapidly and are tracked
+// outside of channelz.
+type EphemeralSocketMetrics struct {
+	// The amount of window, granted to the local endpoint by the remote endpoint.
+	// This may be slightly out of date due to network latency.  This does NOT
+	// include stream level or TCP level flow control info.
+	LocalFlowControlWindow int64
+	// The amount of window, granted to the remote endpoint by the local endpoint.
+	// This may be slightly out of date due to network latency.  This does NOT
+	// include stream level or TCP level flow control info.
+	RemoteFlowControlWindow int64
+}
+
+type SocketType string
+
+const (
+	SocketTypeNormal = "NormalSocket"
+	SocketTypeListen = "ListenSocket"
+)
+
+type Socket struct {
+	Entity
+	SocketType       SocketType
+	ID               int64
+	Parent           Entity
+	cm               *channelMap
+	SocketMetrics    SocketMetrics
+	EphemeralMetrics func() *EphemeralSocketMetrics
+
+	RefName string
+	// The locally bound address.  Immutable.
+	LocalAddr net.Addr
+	// The remote bound address.  May be absent.  Immutable.
+	RemoteAddr net.Addr
+	// Optional, represents the name of the remote endpoint, if different than
+	// the original target name.  Immutable.
+	RemoteName string
+	// Immutable.
+	SocketOptions *SocketOptionData
+	// Immutable.
+	Security credentials.ChannelzSecurityValue
+}
+
+func (ls *Socket) String() string {
+	return fmt.Sprintf("%s %s #%d", ls.Parent, ls.SocketType, ls.ID)
+}
+
+func (ls *Socket) id() int64 {
+	return ls.ID
+}
+
+func (ls *Socket) addChild(id int64, e entry) {
+	logger.Errorf("cannot add a child (id = %d) of type %T to a listen socket", id, e)
+}
+
+func (ls *Socket) deleteChild(id int64) {
+	logger.Errorf("cannot delete a child (id = %d) from a listen socket", id)
+}
+
+func (ls *Socket) triggerDelete() {
+	ls.cm.deleteEntry(ls.ID)
+	ls.Parent.(entry).deleteChild(ls.ID)
+}
+
+func (ls *Socket) deleteSelfIfReady() {
+	logger.Errorf("cannot call deleteSelfIfReady on a listen socket")
+}
+
+func (ls *Socket) getParentID() int64 {
+	return ls.Parent.id()
+}

vendor/google.golang.org/grpc/internal/channelz/subchannel.go

@@ -0,0 +1,151 @@
+/*
+ *
+ * Copyright 2024 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package channelz
+
+import (
+	"fmt"
+	"sync/atomic"
+)
+
+// SubChannel is the channelz representation of a subchannel.
+type SubChannel struct {
+	Entity
+	// ID is the channelz id of this subchannel.
+	ID int64
+	// RefName is the human readable reference string of this subchannel.
+	RefName       string
+	closeCalled   bool
+	sockets       map[int64]string
+	parent        *Channel
+	trace         *ChannelTrace
+	traceRefCount int32
+
+	ChannelMetrics ChannelMetrics
+}
+
+func (sc *SubChannel) String() string {
+	return fmt.Sprintf("%s SubChannel #%d", sc.parent, sc.ID)
+}
+
+func (sc *SubChannel) id() int64 {
+	return sc.ID
+}
+
+func (sc *SubChannel) Sockets() map[int64]string {
+	db.mu.RLock()
+	defer db.mu.RUnlock()
+	return copyMap(sc.sockets)
+}
+
+func (sc *SubChannel) Trace() *ChannelTrace {
+	db.mu.RLock()
+	defer db.mu.RUnlock()
+	return sc.trace.copy()
+}
+
+func (sc *SubChannel) addChild(id int64, e entry) {
+	if v, ok := e.(*Socket); ok && v.SocketType == SocketTypeNormal {
+		sc.sockets[id] = v.RefName
+	} else {
+		logger.Errorf("cannot add a child (id = %d) of type %T to a subChannel", id, e)
+	}
+}
+
+func (sc *SubChannel) deleteChild(id int64) {
+	delete(sc.sockets, id)
+	sc.deleteSelfIfReady()
+}
+
+func (sc *SubChannel) triggerDelete() {
+	sc.closeCalled = true
+	sc.deleteSelfIfReady()
+}
+
+func (sc *SubChannel) getParentID() int64 {
+	return sc.parent.ID
+}
+
+// deleteSelfFromTree tries to delete the subchannel from the channelz entry relation tree, which
+// means deleting the subchannel reference from its parent's child list.
+//
+// In order for a subchannel to be deleted from the tree, it must meet the criteria that, removal of
+// the corresponding grpc object has been invoked, and the subchannel does not have any children left.
+//
+// The returned boolean value indicates whether the channel has been successfully deleted from tree.
+func (sc *SubChannel) deleteSelfFromTree() (deleted bool) {
+	if !sc.closeCalled || len(sc.sockets) != 0 {
+		return false
+	}
+	sc.parent.deleteChild(sc.ID)
+	return true
+}
+
+// deleteSelfFromMap checks whether it is valid to delete the subchannel from the map, which means
+// deleting the subchannel from channelz's tracking entirely. Users can no longer use id to query
+// the subchannel, and its memory will be garbage collected.
+//
+// The trace reference count of the subchannel must be 0 in order to be deleted from the map. This is
+// specified in the channel tracing gRFC that as long as some other trace has reference to an entity,
+// the trace of the referenced entity must not be deleted. In order to release the resource allocated
+// by grpc, the reference to the grpc object is reset to a dummy object.
+//
+// deleteSelfFromMap must be called after deleteSelfFromTree returns true.
+//
+// It returns a bool to indicate whether the channel can be safely deleted from map.
+func (sc *SubChannel) deleteSelfFromMap() (delete bool) {
+	return sc.getTraceRefCount() == 0
+}
+
+// deleteSelfIfReady tries to delete the subchannel itself from the channelz database.
+// The delete process includes two steps:
+//  1. delete the subchannel from the entry relation tree, i.e. delete the subchannel reference from
+//     its parent's child list.
+//  2. delete the subchannel from the map, i.e. delete the subchannel entirely from channelz. Lookup
+//     by id will return entry not found error.
+func (sc *SubChannel) deleteSelfIfReady() {
+	if !sc.deleteSelfFromTree() {
+		return
+	}
+	if !sc.deleteSelfFromMap() {
+		return
+	}
+	db.deleteEntry(sc.ID)
+	sc.trace.clear()
+}
+
+func (sc *SubChannel) getChannelTrace() *ChannelTrace {
+	return sc.trace
+}
+
+func (sc *SubChannel) incrTraceRefCount() {
+	atomic.AddInt32(&sc.traceRefCount, 1)
+}
+
+func (sc *SubChannel) decrTraceRefCount() {
+	atomic.AddInt32(&sc.traceRefCount, -1)
+}
+
+func (sc *SubChannel) getTraceRefCount() int {
+	i := atomic.LoadInt32(&sc.traceRefCount)
+	return int(i)
+}
+
+func (sc *SubChannel) getRefName() string {
+	return sc.RefName
+}

vendor/google.golang.org/grpc/internal/channelz/syscall_linux.go

@@ -0,0 +1,65 @@
+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package channelz
+
+import (
+	"syscall"
+
+	"golang.org/x/sys/unix"
+)
+
+// SocketOptionData defines the struct to hold socket option data, and related
+// getter function to obtain info from fd.
+type SocketOptionData struct {
+	Linger      *unix.Linger
+	RecvTimeout *unix.Timeval
+	SendTimeout *unix.Timeval
+	TCPInfo     *unix.TCPInfo
+}
+
+// Getsockopt defines the function to get socket options requested by channelz.
+// It is to be passed to syscall.RawConn.Control().
+func (s *SocketOptionData) Getsockopt(fd uintptr) {
+	if v, err := unix.GetsockoptLinger(int(fd), syscall.SOL_SOCKET, syscall.SO_LINGER); err == nil {
+		s.Linger = v
+	}
+	if v, err := unix.GetsockoptTimeval(int(fd), syscall.SOL_SOCKET, syscall.SO_RCVTIMEO); err == nil {
+		s.RecvTimeout = v
+	}
+	if v, err := unix.GetsockoptTimeval(int(fd), syscall.SOL_SOCKET, syscall.SO_SNDTIMEO); err == nil {
+		s.SendTimeout = v
+	}
+	if v, err := unix.GetsockoptTCPInfo(int(fd), syscall.SOL_TCP, syscall.TCP_INFO); err == nil {
+		s.TCPInfo = v
+	}
+}
+
+// GetSocketOption gets the socket option info of the conn.
+func GetSocketOption(socket any) *SocketOptionData {
+	c, ok := socket.(syscall.Conn)
+	if !ok {
+		return nil
+	}
+	data := &SocketOptionData{}
+	if rawConn, err := c.SyscallConn(); err == nil {
+		rawConn.Control(data.Getsockopt)
+		return data
+	}
+	return nil
+}

vendor/google.golang.org/grpc/internal/channelz/syscall_nonlinux.go

@@ -0,0 +1,47 @@
+//go:build !linux
+
+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package channelz
+
+import (
+	"sync"
+)
+
+var once sync.Once
+
+// SocketOptionData defines the struct to hold socket option data, and related
+// getter function to obtain info from fd.
+// Windows OS doesn't support Socket Option
+type SocketOptionData struct {
+}
+
+// Getsockopt defines the function to get socket options requested by channelz.
+// It is to be passed to syscall.RawConn.Control().
+// Windows OS doesn't support Socket Option
+func (s *SocketOptionData) Getsockopt(fd uintptr) {
+	once.Do(func() {
+		logger.Warning("Channelz: socket options are not supported on non-linux environments")
+	})
+}
+
+// GetSocketOption gets the socket option info of the conn.
+func GetSocketOption(c any) *SocketOptionData {
+	return nil
+}

vendor/google.golang.org/grpc/internal/channelz/trace.go

@@ -0,0 +1,204 @@
+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package channelz
+
+import (
+	"fmt"
+	"sync"
+	"sync/atomic"
+	"time"
+
+	"google.golang.org/grpc/grpclog"
+)
+
+const (
+	defaultMaxTraceEntry int32 = 30
+)
+
+var maxTraceEntry = defaultMaxTraceEntry
+
+// SetMaxTraceEntry sets maximum number of trace entries per entity (i.e.
+// channel/subchannel).  Setting it to 0 will disable channel tracing.
+func SetMaxTraceEntry(i int32) {
+	atomic.StoreInt32(&maxTraceEntry, i)
+}
+
+// ResetMaxTraceEntryToDefault resets the maximum number of trace entries per
+// entity to default.
+func ResetMaxTraceEntryToDefault() {
+	atomic.StoreInt32(&maxTraceEntry, defaultMaxTraceEntry)
+}
+
+func getMaxTraceEntry() int {
+	i := atomic.LoadInt32(&maxTraceEntry)
+	return int(i)
+}
+
+// traceEvent is an internal representation of a single trace event
+type traceEvent struct {
+	// Desc is a simple description of the trace event.
+	Desc string
+	// Severity states the severity of this trace event.
+	Severity Severity
+	// Timestamp is the event time.
+	Timestamp time.Time
+	// RefID is the id of the entity that gets referenced in the event. RefID is 0 if no other entity is
+	// involved in this event.
+	// e.g. SubChannel (id: 4[]) Created. --> RefID = 4, RefName = "" (inside [])
+	RefID int64
+	// RefName is the reference name for the entity that gets referenced in the event.
+	RefName string
+	// RefType indicates the referenced entity type, i.e Channel or SubChannel.
+	RefType RefChannelType
+}
+
+// TraceEvent is what the caller of AddTraceEvent should provide to describe the
+// event to be added to the channel trace.
+//
+// The Parent field is optional. It is used for an event that will be recorded
+// in the entity's parent trace.
+type TraceEvent struct {
+	Desc     string
+	Severity Severity
+	Parent   *TraceEvent
+}
+
+type ChannelTrace struct {
+	cm           *channelMap
+	clearCalled  bool
+	CreationTime time.Time
+	EventNum     int64
+	mu           sync.Mutex
+	Events       []*traceEvent
+}
+
+func (c *ChannelTrace) copy() *ChannelTrace {
+	return &ChannelTrace{
+		CreationTime: c.CreationTime,
+		EventNum:     c.EventNum,
+		Events:       append(([]*traceEvent)(nil), c.Events...),
+	}
+}
+
+func (c *ChannelTrace) append(e *traceEvent) {
+	c.mu.Lock()
+	if len(c.Events) == getMaxTraceEntry() {
+		del := c.Events[0]
+		c.Events = c.Events[1:]
+		if del.RefID != 0 {
+			// start recursive cleanup in a goroutine to not block the call originated from grpc.
+			go func() {
+				// need to acquire c.cm.mu lock to call the unlocked attemptCleanup func.
+				c.cm.mu.Lock()
+				c.cm.decrTraceRefCount(del.RefID)
+				c.cm.mu.Unlock()
+			}()
+		}
+	}
+	e.Timestamp = time.Now()
+	c.Events = append(c.Events, e)
+	c.EventNum++
+	c.mu.Unlock()
+}
+
+func (c *ChannelTrace) clear() {
+	if c.clearCalled {
+		return
+	}
+	c.clearCalled = true
+	c.mu.Lock()
+	for _, e := range c.Events {
+		if e.RefID != 0 {
+			// caller should have already held the c.cm.mu lock.
+			c.cm.decrTraceRefCount(e.RefID)
+		}
+	}
+	c.mu.Unlock()
+}
+
+// Severity is the severity level of a trace event.
+// The canonical enumeration of all valid values is here:
+// https://github.com/grpc/grpc-proto/blob/9b13d199cc0d4703c7ea26c9c330ba695866eb23/grpc/channelz/v1/channelz.proto#L126.
+type Severity int
+
+const (
+	// CtUnknown indicates unknown severity of a trace event.
+	CtUnknown Severity = iota
+	// CtInfo indicates info level severity of a trace event.
+	CtInfo
+	// CtWarning indicates warning level severity of a trace event.
+	CtWarning
+	// CtError indicates error level severity of a trace event.
+	CtError
+)
+
+// RefChannelType is the type of the entity being referenced in a trace event.
+type RefChannelType int
+
+const (
+	// RefUnknown indicates an unknown entity type, the zero value for this type.
+	RefUnknown RefChannelType = iota
+	// RefChannel indicates the referenced entity is a Channel.
+	RefChannel
+	// RefSubChannel indicates the referenced entity is a SubChannel.
+	RefSubChannel
+	// RefServer indicates the referenced entity is a Server.
+	RefServer
+	// RefListenSocket indicates the referenced entity is a ListenSocket.
+	RefListenSocket
+	// RefNormalSocket indicates the referenced entity is a NormalSocket.
+	RefNormalSocket
+)
+
+var refChannelTypeToString = map[RefChannelType]string{
+	RefUnknown:      "Unknown",
+	RefChannel:      "Channel",
+	RefSubChannel:   "SubChannel",
+	RefServer:       "Server",
+	RefListenSocket: "ListenSocket",
+	RefNormalSocket: "NormalSocket",
+}
+
+func (r RefChannelType) String() string {
+	return refChannelTypeToString[r]
+}
+
+// AddTraceEvent adds trace related to the entity with specified id, using the
+// provided TraceEventDesc.
+//
+// If channelz is not turned ON, this will simply log the event descriptions.
+func AddTraceEvent(l grpclog.DepthLoggerV2, e Entity, depth int, desc *TraceEvent) {
+	// Log only the trace description associated with the bottom most entity.
+	d := fmt.Sprintf("[%s]%s", e, desc.Desc)
+	switch desc.Severity {
+	case CtUnknown, CtInfo:
+		l.InfoDepth(depth+1, d)
+	case CtWarning:
+		l.WarningDepth(depth+1, d)
+	case CtError:
+		l.ErrorDepth(depth+1, d)
+	}
+
+	if getMaxTraceEntry() == 0 {
+		return
+	}
+	if IsOn() {
+		db.traceEvent(e.id(), desc)
+	}
+}