package cmd

import (
	"context"
	"os"
	"reflect"
	"sync"
	"testing"

	"github.com/minio/minio/internal/dsync"
)

// Helper function to create a lock server for testing
func createLockTestServer(ctx context.Context, t *testing.T) (string, *lockRESTServer, string) {
	obj, fsDir, err := prepareFS(ctx)
	if err != nil {
		t.Fatal(err)
	}

			Source:    t.Name(),
			Owner:     "owner",
			Quorum:    &quorum,
		}
		ok, err := l.RLock(ctx, arg)
		if err != nil {
			t.Fatal(err)
		}
		if !ok {
			t.Fatal("did not get read lock")
		}
		// RLock twice
		ok, err = l.RLock(ctx, arg)
		if err != nil {
			t.Fatal(err)
		}
		if !ok {
			t.Fatal("did not get write lock")
		}

		rResources[i] = arg.Resources[0]
	}

### Locks

We have 3 different things that we synchronize on.

#### Http2Connection

This lock guards internal state of each connection. This lock is never held for blocking operations. That means that we acquire the lock, read or write a few fields and release the lock. No I/O and no application-layer callbacks.

#### Http2Stream

pkg encoding/pem, func Decode([]uint8) (*Block, []uint8)
pkg encoding/pem, func Encode(io.Writer, *Block) error
pkg encoding/pem, func EncodeToMemory(*Block) []uint8
pkg encoding/pem, type Block struct
pkg encoding/pem, type Block struct, Bytes []uint8
pkg encoding/pem, type Block struct, Headers map[string]string
pkg encoding/pem, type Block struct, Type string
pkg encoding/xml, const Header ideal-string

	h.status.Store(statusClosed)
	h.storeCtxCancel()

	// Wait for messages to be sent...
	h.wg.Wait()

	// Set logch to nil and close it.
	// This will block all Send operations,
	// and finish the existing ones.
	// All future ones will be discarded.
	h.logChMu.Lock()
	xioutil.SafeClose(h.logCh)
	h.logCh = nil
	h.logChMu.Unlock()

func (sys *BucketTargetSys) isOffline(ep *url.URL) bool {
	sys.hMutex.RLock()
	defer sys.hMutex.RUnlock()
	if h, ok := sys.hc[ep.Host]; ok {
		return !h.Online
	}
	go sys.initHC(ep)
	return false
}

// markOffline sets endpoint to offline if network i/o timeout seen.
func (sys *BucketTargetSys) markOffline(ep *url.URL) {
	sys.hMutex.Lock()
	defer sys.hMutex.Unlock()
	if h, ok := sys.hc[ep.Host]; ok {

Yuri Schimke <******@****.***> 1690028931 +0100

		time.Sleep(time.Duration(d))
	}

	l.mutex.Lock()
	defer l.mutex.Unlock()
	var locksHeld int64
	if locksHeld, reply = l.lockMap[args.Resources[0]]; !reply { // No lock is held on the given name
		return false, fmt.Errorf("RUnlock attempted on an unlocked entity: %s", args.Resources[0])
	}
	if reply = locksHeld != WriteLock; !reply { // A write-lock is held, cannot release a read lock

}

// List - returns available target IDs.
func (list *TargetList) List() []TargetID {
	list.RLock()
	defer list.RUnlock()

	keys := []TargetID{}
	for k := range list.targets {
		keys = append(keys, k)
	}

	return keys
}

func (list *TargetList) get(id TargetID) (Target, bool) {
	list.RLock()
	defer list.RUnlock()

	target, ok := list.targets[id]
	return target, ok
}

func (m *metacacheManager) deleteBucketCache(bucket string) {
	m.init.Do(m.initManager)
	m.mu.Lock()
	b, ok := m.buckets[bucket]
	if !ok {
		m.mu.Unlock()
		return
	}
	delete(m.buckets, bucket)
	m.mu.Unlock()

	// Since deletes may take some time we try to do it without
	// holding lock to m all the time.
	b.mu.Lock()
	defer b.mu.Unlock()
	for k, v := range b.caches {