From 91c51f4807aa3458a0ebd03c6cc92d578e01028b Mon Sep 17 00:00:00 2001
From: Jarek Kowalski <jaak@jkowalski.net>
Date: Sat, 23 Jun 2018 13:05:40 -0700
Subject: [PATCH] refactored 'block gc' subcommand

---
 block/block_manager.go  | 37 ++++++++++++++++++++++++++++++
 cli/command_block_gc.go | 50 +++++++----------------------------------
 2 files changed, 45 insertions(+), 42 deletions(-)

diff --git a/block/block_manager.go b/block/block_manager.go
index 6c721fc35..d95af8a4f 100644
--- a/block/block_manager.go
+++ b/block/block_manager.go
@@ -863,6 +863,43 @@ func (bm *Manager) BlockInfo(ctx context.Context, blockID string) (Info, error)
 	return bm.packedBlockInfoLocked(blockID)
 }
 
+// FindUnreferencedStorageFiles returns the list of unreferenced storage blocks.
+func (bm *Manager) FindUnreferencedStorageFiles(ctx context.Context) ([]storage.BlockMetadata, error) {
+	infos, err := bm.ListBlockInfos("", false)
+	if err != nil {
+		return nil, fmt.Errorf("unable to list index blocks: %v", err)
+	}
+
+	usedPackBlocks := findPackBlocksInUse(infos)
+	ch := bm.st.ListBlocks(ctx, PackBlockPrefix)
+
+	var unused []storage.BlockMetadata
+	for bi := range ch {
+		if bi.Error != nil {
+			return nil, fmt.Errorf("error listing storage blocks: %v", bi.Error)
+		}
+
+		u := usedPackBlocks[bi.BlockID]
+		if u > 0 {
+			log.Printf("pack %v, in use by %v blocks", bi.BlockID, u)
+			continue
+		}
+
+		unused = append(unused, bi)
+	}
+	return unused, nil
+}
+
+func findPackBlocksInUse(infos []Info) map[string]int {
+	packUsage := map[string]int{}
+
+	for _, bi := range infos {
+		packUsage[bi.PackFile]++
+	}
+
+	return packUsage
+}
+
 func (bm *Manager) packedBlockInfoLocked(blockID string) (Info, error) {
 	bm.assertLocked()
 
diff --git a/cli/command_block_gc.go b/cli/command_block_gc.go
index 27cc44117..dd92157f5 100644
--- a/cli/command_block_gc.go
+++ b/cli/command_block_gc.go
@@ -5,9 +5,7 @@
 	"fmt"
 	"os"
 
-	"github.com/kopia/kopia/block"
 	"github.com/kopia/kopia/repo"
-	"github.com/rs/zerolog/log"
 )
 
 var (
@@ -16,43 +14,21 @@
 )
 
 func runBlockGarbageCollectAction(ctx context.Context, rep *repo.Repository) error {
-	infos, err := rep.Blocks.ListBlockInfos("", false)
+	unused, err := rep.Blocks.FindUnreferencedStorageFiles(ctx)
 	if err != nil {
-		return fmt.Errorf("unable to list index blocks: %v", err)
+		return fmt.Errorf("error looking for unreferenced storage files: %v", err)
 	}
 
-	usedPackBlocks := findPackBlocksInUse(infos)
-	ch := rep.Storage.ListBlocks(ctx, block.PackBlockPrefix)
-
-	var unused []string
-	var totalBytes int64
-	allPackBlocks := 0
-	for bi := range ch {
-		if bi.Error != nil {
-			return fmt.Errorf("error listing storage blocks: %v", bi.Error)
-		}
-
-		allPackBlocks++
-
-		u := usedPackBlocks[bi.BlockID]
-		if u > 0 {
-			log.Printf("pack %v, in use by %v blocks", bi.BlockID, u)
-			continue
-		}
-
-		totalBytes += bi.Length
-		unused = append(unused, bi.BlockID)
-	}
-	fmt.Fprintf(os.Stderr, "Found %v/%v pack blocks in use.\n", len(usedPackBlocks), allPackBlocks)
-
 	if len(unused) == 0 {
 		fmt.Fprintf(os.Stderr, "No unused blocks found.\n")
 		return nil
 	}
 
 	if *blockGarbageCollectCommandDelete != "yes" {
+		var totalBytes int64
 		for _, u := range unused {
-			fmt.Fprintf(os.Stderr, "unused %v\n", u)
+			fmt.Fprintf(os.Stderr, "unused %v (%v bytes)\n", u.BlockID, u.Length)
+			totalBytes += u.Length
 		}
 		fmt.Fprintf(os.Stderr, "Would delete %v unused blocks (%v bytes), pass '--delete=yes' to actually delete.\n", len(unused), totalBytes)
 
@@ -60,25 +36,15 @@ func runBlockGarbageCollectAction(ctx context.Context, rep *repo.Repository) err
 	}
 
 	for _, u := range unused {
-		fmt.Fprintf(os.Stderr, "Deleting unused block %q...\n", u)
-		if err := rep.Storage.DeleteBlock(ctx, u); err != nil {
-			return fmt.Errorf("unable to delete block %q: %v", u, err)
+		fmt.Fprintf(os.Stderr, "Deleting unused block %q (%v bytes)...\n", u.BlockID, u.Length)
+		if err := rep.Storage.DeleteBlock(ctx, u.BlockID); err != nil {
+			return fmt.Errorf("unable to delete block %q: %v", u.BlockID, err)
 		}
 	}
 
 	return nil
 }
 
-func findPackBlocksInUse(infos []block.Info) map[string]int {
-	packUsage := map[string]int{}
-
-	for _, bi := range infos {
-		packUsage[bi.PackFile]++
-	}
-
-	return packUsage
-}
-
 func init() {
 	blockGarbageCollectCommand.Action(repositoryAction(runBlockGarbageCollectAction))
 }