Fix file ordinals

pkg/database/keyvalue/block/database.go

@@ -12,6 +12,7 @@ import (
 	"io/fs"
 	"os"
 	"path/filepath"
+	"slices"
 	"sync"
 
 	"gitlab.com/accumulatenetwork/accumulate/pkg/database"
@@ -28,7 +29,8 @@ type Database struct {
 	records   records
 	next      uint64
 	fileLimit uint64
-	nameFn    func(i int) string
+	nameFmt   NameFormat
+	filterFn  func(string) bool
 }
 
 type records = vmap[[32]byte, recordLocation]
@@ -55,9 +57,15 @@ func WithFileLimit(limit uint64) Option {
 	}
 }
 
-func WithNameFunc(fn func(i int) string) Option {
+func WithNameFormat(fmt NameFormat) Option {
 	return func(d *Database) {
-		d.nameFn = fn
+		d.nameFmt = fmt
+	}
+}
+
+func FilterFiles(fn func(string) bool) Option {
+	return func(d *Database) {
+		d.filterFn = fn
 	}
 }
 
@@ -83,7 +91,7 @@ func Open(path string, options ...Option) (_ *Database, err error) {
 
 	db.path = path
 	db.fileLimit = 1 << 30
-	db.nameFn = func(i int) string { return fmt.Sprintf("%d.blocks", i) }
+	db.nameFmt = DefaultNameFormat
 
 	for _, o := range options {
 		o(db)
@@ -92,14 +100,30 @@ func Open(path string, options ...Option) (_ *Database, err error) {
 	// Open all the files
 	db.files = make([]*blockFile, 0, len(entries))
 	for _, e := range entries {
-		f, err := openFile(filepath.Join(path, e.Name()), os.O_RDWR, 0)
+		if db.filterFn != nil && !db.filterFn(e.Name()) {
+			continue
+		}
+
+		// Extract the ordinal from the filename
+		number, err := db.nameFmt.Parse(e.Name())
+		if err != nil {
+			return nil, fmt.Errorf("parse index of %q: %w", e.Name(), err)
+		}
+
+		f, err := openFile(number, filepath.Join(path, e.Name()), os.O_RDWR, 0)
 		if err != nil {
 			return nil, err
 		}
 
 		db.files = append(db.files, f)
 	}
 
+	// Sort the files by number, since who knows what order the filesystem
+	// returns them in
+	slices.SortFunc(db.files, func(a, b *blockFile) int {
+		return a.number - b.number
+	})
+
 	// Build the block index
 	blocks := map[uint64]blockLocation{}
 	records := db.records.View()
@@ -177,15 +201,16 @@ func (db *Database) newFile() (*blockFile, error) {
 	}
 
 	// Create a new file
-	name := db.nameFn(len(db.files))
+	number := len(db.files)
+	name := db.nameFmt.Format(number)
 	if name == "" {
 		return nil, fmt.Errorf("invalid block file name: empty")
 	} else if filepath.Base(name) != name {
 		return nil, fmt.Errorf("invalid block file name: %q contains a slash or is empty", name)
 	}
 	name = filepath.Join(db.path, name)
 
-	f, err := openFile(name, os.O_RDWR|os.O_EXCL|os.O_CREATE, 0600)
+	f, err := openFile(number, name, os.O_RDWR|os.O_EXCL|os.O_CREATE, 0600)
 	if err != nil {
 		return nil, err
 	}

pkg/database/keyvalue/block/file.go

@@ -17,13 +17,15 @@ import (
 )
 
 type blockFile struct {
-	file *os.File
-	mu   *sync.RWMutex
-	data mmap.MMap
+	number int
+	mu     *sync.RWMutex
+	file   *os.File
+	data   mmap.MMap
 }
 
-func openFile(name string, flag int, perm fs.FileMode) (*blockFile, error) {
+func openFile(number int, name string, flag int, perm fs.FileMode) (*blockFile, error) {
 	f := new(blockFile)
+	f.number = number
 	f.mu = new(sync.RWMutex)
 
 	var err error

pkg/database/keyvalue/block/format.go

@@ -0,0 +1,32 @@
+// Copyright 2024 The Accumulate Authors
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file or at
+// https://opensource.org/licenses/MIT.
+
+package block
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+)
+
+var DefaultNameFormat = simpleNameFormat{}
+
+type NameFormat interface {
+	Format(int) string
+	Parse(string) (int, error)
+}
+
+type simpleNameFormat struct{}
+
+func (simpleNameFormat) Format(i int) string {
+	return fmt.Sprintf("%d.blocks", i)
+}
+
+func (simpleNameFormat) Parse(s string) (int, error) {
+	s = strings.TrimSuffix(s, ".blocks")
+	i, err := strconv.ParseInt(s, 10, 64)
+	return int(i), err
+}