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[onechat] / records.go

diff --git a/records.go b/records.go
index 73a9d8323ad433c75594838262cb5f399c030e8e..abd88a897a99e63c07f3955cc0f4b96a1c41b0cb 100644 (file)
--- a/records.go
+++ b/records.go
@@ -11,19 +11,9 @@ import (
 // positionBytes is the size of an encoded position.
 const positionBytes = 16
 
-// records is a file of fixed-size records, numbered from 0. Record n starts at
-// byte n*size. A record that was never written reads as zeros. An index is data
-// that the day files can give again, so records cuts a partial record at the
-// end of the file.
-type records struct {
-       file  *os.File
-       size  int
-       count int
-}
-
 // openRecords opens or creates the record file at path with records of size
 // bytes.
-func openRecords(path string, size int) (*records, error) {
+func openRecords(path string, size int) (*Records, error) {
        file, err := os.OpenFile(path, os.O_CREATE|os.O_RDWR, 0o600)
        if err != nil {
                return nil, fmt.Errorf("open index: %w", err)
@@ -34,7 +24,7 @@ func openRecords(path string, size int) (*records, error) {
                return nil, errors.Join(fmt.Errorf("read index size: %w", err), file.Close())
        }
 
-       r := &records{
+       r := &Records{
                file:  file,
                size:  size,
                count: int(info.Size()) / size,
@@ -50,8 +40,34 @@ func openRecords(path string, size int) (*records, error) {
        return r, nil
 }
 
+// encodePosition writes place into the first positionBytes bytes of record.
+func encodePosition(record []byte, place Position) {
+       binary.LittleEndian.PutUint32(record[0:], place.day)
+       binary.LittleEndian.PutUint32(record[4:], place.length)
+       binary.LittleEndian.PutUint64(record[8:], place.offset)
+}
+
+// decodePosition reads a position from the first positionBytes bytes of record.
+func decodePosition(record []byte) Position {
+       return Position{
+               day:    binary.LittleEndian.Uint32(record[0:]),
+               length: binary.LittleEndian.Uint32(record[4:]),
+               offset: binary.LittleEndian.Uint64(record[8:]),
+       }
+}
+
+// Records is a file of fixed-size Records, numbered from 0. Record n starts at
+// byte n*size. A record that was never written reads as zeros. An index is data
+// that the day files can give again, so Records cuts a partial record at the
+// end of the file.
+type Records struct {
+       file  *os.File
+       size  int
+       count int
+}
+
 // Read returns record n, or false when the file does not reach it.
-func (r *records) Read(n int) ([]byte, bool, error) {
+func (r *Records) Read(n int) ([]byte, bool, error) {
        if n >= r.count {
                return nil, false, nil
        }
@@ -66,7 +82,7 @@ func (r *records) Read(n int) ([]byte, bool, error) {
 }
 
 // Write writes record n.
-func (r *records) Write(n int, record []byte) error {
+func (r *Records) Write(n int, record []byte) error {
        _, err := r.file.WriteAt(record, int64(n*r.size))
        if err != nil {
                return fmt.Errorf("write index record %d: %w", n, err)
@@ -78,27 +94,11 @@ func (r *records) Write(n int, record []byte) error {
 }
 
 // Append writes the record after the last one.
-func (r *records) Append(record []byte) error {
+func (r *Records) Append(record []byte) error {
        return r.Write(r.count, record)
 }
 
 // Close closes the file.
-func (r *records) Close() error {
+func (r *Records) Close() error {
        return r.file.Close()
 }
-
-// encodePosition writes place into the first positionBytes bytes of record.
-func encodePosition(record []byte, place position) {
-       binary.LittleEndian.PutUint32(record[0:], place.day)
-       binary.LittleEndian.PutUint32(record[4:], place.length)
-       binary.LittleEndian.PutUint64(record[8:], place.offset)
-}
-
-// decodePosition reads a position from the first positionBytes bytes of record.
-func decodePosition(record []byte) position {
-       return position{
-               day:    binary.LittleEndian.Uint32(record[0:]),
-               length: binary.LittleEndian.Uint32(record[4:]),
-               offset: binary.LittleEndian.Uint64(record[8:]),
-       }
-}