1 files changed, 75 insertions, 0 deletions
diff --git a/cmd/btrfs-rec/inspect_rebuildtrees.go b/cmd/btrfs-rec/inspect_rebuildtrees.go
new file mode 100644
index 0000000..0b41dd9
--- /dev/null
+++ b/cmd/btrfs-rec/inspect_rebuildtrees.go
@@ -0,0 +1,75 @@
+// Copyright (C) 2022-2023  Luke Shumaker <lukeshu@lukeshu.com>
+//
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+package main
+
+import (
+	"context"
+	"os"
+	"runtime"
+	"time"
+
+	"git.lukeshu.com/go/lowmemjson"
+	"github.com/datawire/dlib/dlog"
+	"github.com/datawire/ocibuild/pkg/cliutil"
+	"github.com/spf13/cobra"
+
+	"git.lukeshu.com/btrfs-progs-ng/cmd/btrfs-rec/inspect/rebuildmappings"
+	"git.lukeshu.com/btrfs-progs-ng/cmd/btrfs-rec/inspect/rebuildtrees"
+	"git.lukeshu.com/btrfs-progs-ng/lib/btrfs"
+	"git.lukeshu.com/btrfs-progs-ng/lib/textui"
+)
+
+func init() {
+	inspectors = append(inspectors, subcommand{
+		Command: cobra.Command{
+			Use:  "rebuild-nodes NODESCAN.json",
+			Args: cliutil.WrapPositionalArgs(cobra.ExactArgs(1)),
+		},
+		RunE: func(fs *btrfs.FS, cmd *cobra.Command, args []string) error {
+			ctx := cmd.Context()
+
+			// This is wrapped in a func in order to *ensure* that `nodeScanResults` goes out of scope once
+			// `rebuilder` has been created.
+			rebuilder, err := func(ctx context.Context) (rebuildtrees.Rebuilder, error) {
+				dlog.Infof(ctx, "Reading %q...", args[0])
+				nodeScanResults, err := readJSONFile[rebuildmappings.ScanDevicesResult](ctx, args[0])
+				if err != nil {
+					return nil, err
+				}
+				dlog.Infof(ctx, "... done reading %q", args[0])
+
+				return rebuildtrees.NewRebuilder(ctx, fs, nodeScanResults)
+			}(ctx)
+			if err != nil {
+				return err
+			}
+
+			runtime.GC()
+			time.Sleep(textui.LiveMemUseUpdateInterval) // let the logs reflect that GC right away
+
+			dlog.Info(ctx, "Rebuilding node tree...")
+			rebuildErr := rebuilder.Rebuild(ctx)
+			dst := os.Stdout
+			if rebuildErr != nil {
+				dst = os.Stderr
+				dlog.Errorf(ctx, "rebuild error: %v", rebuildErr)
+			}
+			dlog.Infof(ctx, "Writing re-built nodes to %s...", dst.Name())
+			if err := writeJSONFile(dst, rebuilder.ListRoots(ctx), lowmemjson.ReEncoderConfig{
+				Indent:                "\t",
+				CompactIfUnder:        80, //nolint:gomnd // This is what looks nice.
+				ForceTrailingNewlines: true,
+			}); err != nil {
+				if rebuildErr != nil {
+					return rebuildErr
+				}
+				return err
+			}
+			dlog.Info(ctx, "... done writing")
+
+			return rebuildErr
+		},
+	})
+}