chore: merge dnscore into rbmk repository

.editorconfig

@@ -0,0 +1,18 @@
+root = true
+
+[*]
+end_of_line = lf
+insert_final_newline = true
+indent_style = tab
+indent_size = 4
+trim_trailing_whitespace = true
+
+[*.txt]
+indent_style = space
+
+[*.conf]
+indent_style = space
+
+[*.yml]
+indent_size = 2
+indent_style = space

go.mod

@@ -4,13 +4,16 @@ go 1.23.3
 
 require (
 	github.com/charmbracelet/glamour v0.10.0
+	github.com/google/go-cmp v0.7.0
 	github.com/miekg/dns v1.1.66
 	github.com/pion/stun/v3 v3.0.0
+	github.com/quic-go/quic-go v0.53.0
 	github.com/rbmk-project/common v0.21.0
-	github.com/rbmk-project/dnscore v0.13.0
 	github.com/rbmk-project/x v0.0.0-20250625213336-5718c136805c
 	github.com/spf13/pflag v1.0.6
 	github.com/stretchr/testify v1.10.0
+	golang.org/x/net v0.41.0
+	golang.org/x/sys v0.33.0
 	mvdan.cc/sh/v3 v3.11.0
 )
 
@@ -37,7 +40,7 @@ require (
 	github.com/pion/logging v0.2.4 // indirect
 	github.com/pion/transport/v3 v3.0.7 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
-	github.com/quic-go/quic-go v0.53.0 // indirect
+	github.com/rbmk-project/dnscore v0.13.0 // indirect
 	github.com/rivo/uniseg v0.4.7 // indirect
 	github.com/rogpeppe/go-internal v1.14.1 // indirect
 	github.com/wlynxg/anet v0.0.5 // indirect
@@ -48,9 +51,7 @@ require (
 	golang.org/x/crypto v0.39.0 // indirect
 	golang.org/x/exp v0.0.0-20250408133849-7e4ce0ab07d0 // indirect
 	golang.org/x/mod v0.25.0 // indirect
-	golang.org/x/net v0.41.0 // indirect
 	golang.org/x/sync v0.15.0 // indirect
-	golang.org/x/sys v0.33.0 // indirect
 	golang.org/x/term v0.32.0 // indirect
 	golang.org/x/text v0.26.0 // indirect
 	golang.org/x/tools v0.34.0 // indirect

pkg/cli/curl/curl.go

@@ -13,9 +13,9 @@ import (
 	"time"
 
 	"github.com/rbmk-project/common/cliutils"
-	"github.com/rbmk-project/common/closepool"
 	"github.com/rbmk-project/common/fsx"
 	"github.com/rbmk-project/rbmk/internal/markdown"
+	"github.com/rbmk-project/rbmk/pkg/common/closepool"
 	"github.com/spf13/pflag"
 )
 

pkg/cli/curl/httplog.go

@@ -8,8 +8,8 @@ import (
 	"net/netip"
 	"time"
 
-	"github.com/rbmk-project/common/httpconntrace"
-	"github.com/rbmk-project/common/httpslog"
+	"github.com/rbmk-project/rbmk/pkg/common/httpconntrace"
+	"github.com/rbmk-project/rbmk/pkg/common/httpslog"
 )
 
 // httpDoAndLog performs the request and emits structured logs.

pkg/cli/curl/task.go

@@ -11,10 +11,10 @@ import (
 	"net/http"
 	"time"
 
-	"github.com/rbmk-project/common/closepool"
 	"github.com/rbmk-project/common/dialonce"
-	"github.com/rbmk-project/dnscore"
 	"github.com/rbmk-project/rbmk/internal/testable"
+	"github.com/rbmk-project/rbmk/pkg/common/closepool"
+	"github.com/rbmk-project/rbmk/pkg/dns/dnscore"
 	"github.com/rbmk-project/x/netcore"
 )
 

pkg/cli/dig/dig.go

@@ -12,9 +12,9 @@ import (
 	"strings"
 
 	"github.com/rbmk-project/common/cliutils"
-	"github.com/rbmk-project/common/closepool"
 	"github.com/rbmk-project/common/fsx"
 	"github.com/rbmk-project/rbmk/internal/markdown"
+	"github.com/rbmk-project/rbmk/pkg/common/closepool"
 	"github.com/spf13/pflag"
 )
 

pkg/cli/dig/task.go

@@ -16,9 +16,9 @@ import (
 	"time"
 
 	"github.com/miekg/dns"
-	"github.com/rbmk-project/common/closepool"
-	"github.com/rbmk-project/dnscore"
 	"github.com/rbmk-project/rbmk/internal/testable"
+	"github.com/rbmk-project/rbmk/pkg/common/closepool"
+	"github.com/rbmk-project/rbmk/pkg/dns/dnscore"
 	"github.com/rbmk-project/x/netcore"
 )
 

pkg/cli/nc/nc.go

@@ -12,9 +12,9 @@ import (
 	"time"
 
 	"github.com/rbmk-project/common/cliutils"
-	"github.com/rbmk-project/common/closepool"
 	"github.com/rbmk-project/common/fsx"
 	"github.com/rbmk-project/rbmk/internal/markdown"
+	"github.com/rbmk-project/rbmk/pkg/common/closepool"
 	"github.com/spf13/pflag"
 )
 

pkg/cli/nc/task.go

@@ -12,8 +12,8 @@ import (
 	"net"
 	"time"
 
-	"github.com/rbmk-project/common/closepool"
 	"github.com/rbmk-project/rbmk/internal/testable"
+	"github.com/rbmk-project/rbmk/pkg/common/closepool"
 	"github.com/rbmk-project/x/netcore"
 )
 

pkg/cli/stun/stun.go

@@ -12,9 +12,9 @@ import (
 	"time"
 
 	"github.com/rbmk-project/common/cliutils"
-	"github.com/rbmk-project/common/closepool"
 	"github.com/rbmk-project/common/fsx"
 	"github.com/rbmk-project/rbmk/internal/markdown"
+	"github.com/rbmk-project/rbmk/pkg/common/closepool"
 	"github.com/spf13/pflag"
 )
 

pkg/cli/stun/task.go

@@ -12,8 +12,8 @@ import (
 	"time"
 
 	"github.com/pion/stun/v3"
-	"github.com/rbmk-project/common/closepool"
 	"github.com/rbmk-project/rbmk/internal/testable"
+	"github.com/rbmk-project/rbmk/pkg/common/closepool"
 	"github.com/rbmk-project/x/netcore"
 )
 

pkg/cli/tar/tar.go

@@ -19,8 +19,8 @@ import (
 	"path/filepath"
 
 	"github.com/rbmk-project/common/cliutils"
-	"github.com/rbmk-project/common/closepool"
 	"github.com/rbmk-project/rbmk/internal/markdown"
+	"github.com/rbmk-project/rbmk/pkg/common/closepool"
 	"github.com/spf13/pflag"
 )
 

pkg/common/closepool/closepool.go

@@ -0,0 +1,63 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+// Package closepool allows pooling [io.Closer] instances
+// and closing them in a single operation.
+package closepool
+
+import (
+	"errors"
+	"io"
+	"slices"
+	"sync"
+)
+
+// CloserFunc allows to turn a suitable function into an [io.Closer].
+type CloserFunc func() error
+
+// Ensure that [CloserFunc] implements [io.Closer].
+var _ io.Closer = CloserFunc(nil)
+
+// Close implements io.Closer.
+func (fx CloserFunc) Close() error {
+	return fx()
+}
+
+// Pool allows pooling a set of [io.Closer].
+//
+// The zero value is ready to use.
+type Pool struct {
+	// handles contains the [io.Closer] to close.
+	handles []io.Closer
+
+	// mu provides mutual exclusion.
+	mu sync.Mutex
+}
+
+// Add adds a given [io.Closer] to the pool.
+func (p *Pool) Add(conn io.Closer) {
+	p.mu.Lock()
+	p.handles = append(p.handles, conn)
+	p.mu.Unlock()
+}
+
+// Close closes all the [io.Closer] inside the pool iterating
+// in backward order. Therefore, if one registers a TCP connection
+// and then the corresponding TLS connection, the TLS connection
+// is closed first. The returned error is the join of all the
+// errors that occurred when closing connections.
+func (p *Pool) Close() error {
+	// Lock and copy the [io.Closer] to close.
+	p.mu.Lock()
+	handles := p.handles
+	p.handles = nil
+	p.mu.Unlock()
+
+	// Close all the [io.Closer].
+	var errv []error
+	for _, handle := range slices.Backward(handles) {
+		if err := handle.Close(); err != nil {
+			errv = append(errv, err)
+		}
+	}
+	return errors.Join(errv...)
+}

pkg/common/closepool/closepool_test.go

@@ -0,0 +1,133 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+package closepool_test
+
+import (
+	"errors"
+	"sync/atomic"
+	"testing"
+	"time"
+
+	"github.com/rbmk-project/rbmk/pkg/common/closepool"
+)
+
+// mockCloser implements io.Closer for testing
+type mockCloser struct {
+	closed atomic.Int64
+	err    error
+}
+
+// t0 is the time when we started running
+var t0 = time.Now()
+
+func (m *mockCloser) Close() error {
+	m.closed.Add(int64(time.Since(t0)))
+	return m.err
+}
+
+func TestCloserFunc(t *testing.T) {
+	var closed bool
+	pool := &closepool.Pool{}
+	pool.Add(closepool.CloserFunc(func() error {
+		closed = true
+		return nil
+	}))
+	pool.Close()
+	if !closed {
+		t.Error("expected closer to be closed")
+	}
+}
+
+func TestPool(t *testing.T) {
+	t.Run("successful close", func(t *testing.T) {
+		pool := closepool.Pool{}
+		m1 := &mockCloser{}
+		m2 := &mockCloser{}
+
+		pool.Add(m1)
+		pool.Add(m2)
+
+		err := pool.Close()
+		if err != nil {
+			t.Errorf("expected no error, got %v", err)
+		}
+
+		if m1.closed.Load() <= 0 {
+			t.Error("first closer was not closed")
+		}
+		if m2.closed.Load() <= 0 {
+			t.Error("second closer was not closed")
+		}
+	})
+
+	t.Run("close order", func(t *testing.T) {
+		pool := closepool.Pool{}
+
+		m1 := &mockCloser{
+			err: nil,
+		}
+		m2 := &mockCloser{
+			err: nil,
+		}
+
+		pool.Add(m1) // Added first
+		pool.Add(m2) // Added second
+
+		// Should close in reverse order
+		err := pool.Close()
+		if err != nil {
+			t.Errorf("expected no error, got %v", err)
+		}
+
+		if m1.closed.Load() <= m2.closed.Load() {
+			t.Error("expected m1 to be closed after m2")
+		}
+	})
+
+	t.Run("error handling", func(t *testing.T) {
+		pool := closepool.Pool{}
+		expectedErr1 := errors.New("close error #1")
+		expectedErr2 := errors.New("close error #2")
+
+		m1 := &mockCloser{err: expectedErr1}
+		m2 := &mockCloser{err: expectedErr2}
+
+		pool.Add(m1)
+		pool.Add(m2)
+
+		err := pool.Close()
+		if err == nil {
+			t.Fatalf("expected error, got nil")
+		}
+
+		t.Log(err)
+		if errors.Join(expectedErr2, expectedErr1).Error() != err.Error() {
+			t.Errorf("expected error to include both errors, got %v", err)
+		}
+	})
+
+	t.Run("concurrent usage", func(t *testing.T) {
+		pool := closepool.Pool{}
+		done := make(chan struct{})
+
+		// Concurrently add closers
+		go func() {
+			for i := 0; i < 100; i++ {
+				pool.Add(&mockCloser{})
+			}
+			close(done)
+		}()
+
+		// Add more closers from main goroutine
+		for i := 0; i < 100; i++ {
+			pool.Add(&mockCloser{})
+		}
+
+		<-done // Wait for goroutine to finish
+
+		err := pool.Close()
+		if err != nil {
+			t.Errorf("expected no error, got %v", err)
+		}
+	})
+}

pkg/common/doc.go

@@ -0,0 +1,10 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+/*
+Package common contains simple, common packages used by other packages.
+
+See [dd-001-common.md] for more information.
+
+[dd-001-common.md]: https://github.com/rbmk-project/rbmk-project.github.io/blob/main/docs/design/dd-001-common.md
+*/
+package common