disk cache: remove list after a write

fix close

block/block_cache.go

@@ -10,6 +10,7 @@ type blockCache interface {
 	getBlock(blockID string, offset, length int64) ([]byte, error)
 	putBlock(blockID string, data []byte) error
 	listIndexBlocks() ([]Info, error)
+	close() error
 }
 
 // CachingOptions specifies configuration of local cache.

block/block_manager.go

@@ -219,11 +219,8 @@ func (bm *Manager) ResetStats() {
 }
 
 // Close closes block manager.
-func (bm *Manager) Close() error {
-	if c, ok := bm.cache.(io.Closer); ok {
-		return c.Close()
-	}
-	return nil
+func (bm *Manager) close() error {
+	return bm.cache.close()
 }
 
 func (bm *Manager) ensurePackGroupLocked(packGroup string, unpacked bool) *packInfo {

block/disk_block_cache.go

@@ -34,7 +34,7 @@ type diskBlockCache struct {
 }
 
 func (c *diskBlockCache) getBlock(blockID string, offset, length int64) ([]byte, error) {
-	fn := filepath.Join(c.directory, blockID) + cachedSuffix
+	fn := c.cachedItemName(blockID)
 
 	b, err := ioutil.ReadFile(fn)
 	if err == nil {
@@ -89,12 +89,12 @@ func (c *diskBlockCache) putBlock(blockID string, data []byte) error {
 	}
 
 	c.writeFileAtomic(filepath.Join(c.directory, blockID)+cachedSuffix, c.appendHMAC(data))
-
+	os.Remove(c.cachedItemName("list"))
 	return nil
 }
 
 func (c *diskBlockCache) listIndexBlocks() ([]Info, error) {
-	cachedListFile := filepath.Join(c.directory, "list"+cachedSuffix)
+	cachedListFile := c.cachedItemName("list")
 	f, err := os.Open(cachedListFile)
 	if err == nil {
 		defer f.Close()
@@ -121,6 +121,10 @@ func (c *diskBlockCache) listIndexBlocks() ([]Info, error) {
 	return blocks, err
 }
 
+func (c *diskBlockCache) cachedItemName(name string) string {
+	return filepath.Join(c.directory, name+cachedSuffix)
+}
+
 func (c *diskBlockCache) readBlocksFromCacheFile(f *os.File) ([]Info, error) {
 	var blocks []Info
 	data, err := ioutil.ReadAll(f)
@@ -210,7 +214,7 @@ func (c *diskBlockCache) writeFileAtomic(fname string, contents []byte) error {
 	return nil
 }
 
-func (c *diskBlockCache) lose() error {
+func (c *diskBlockCache) close() error {
 	close(c.closed)
 	return nil
 }

block/null_block_cache.go

@@ -33,3 +33,7 @@ func (c nullBlockCache) listIndexBlocks() ([]Info, error) {
 
 	return results, nil
 }
+
+func (c nullBlockCache) close() error {
+	return nil
+}