From 77046dcf26687fd74df0f7966d7d469f6b6de717 Mon Sep 17 00:00:00 2001 From: Luke Shumaker Date: Sun, 27 Nov 2022 16:41:44 -0700 Subject: rebuildnodes: Refactor the node-graph stuff in to a separate sub-package --- .../btrfsinspect/rebuildnodes/graph/loops.go | 165 +++++++++++++++++++++ 1 file changed, 165 insertions(+) create mode 100644 lib/btrfsprogs/btrfsinspect/rebuildnodes/graph/loops.go (limited to 'lib/btrfsprogs/btrfsinspect/rebuildnodes/graph/loops.go') diff --git a/lib/btrfsprogs/btrfsinspect/rebuildnodes/graph/loops.go b/lib/btrfsprogs/btrfsinspect/rebuildnodes/graph/loops.go new file mode 100644 index 0000000..e76985c --- /dev/null +++ b/lib/btrfsprogs/btrfsinspect/rebuildnodes/graph/loops.go @@ -0,0 +1,165 @@ +// Copyright (C) 2022 Luke Shumaker +// +// SPDX-License-Identifier: GPL-2.0-or-later + +package graph + +import ( + "fmt" + "io" + "strings" + + "github.com/datawire/dlib/derror" + + "git.lukeshu.com/btrfs-progs-ng/lib/btrfs/btrfsprim" + "git.lukeshu.com/btrfs-progs-ng/lib/btrfs/btrfsvol" + "git.lukeshu.com/btrfs-progs-ng/lib/containers" + "git.lukeshu.com/btrfs-progs-ng/lib/maps" + "git.lukeshu.com/btrfs-progs-ng/lib/slices" +) + +func (g Graph) ShowLoops(out io.Writer) { + orphans := make(containers.Set[btrfsvol.LogicalAddr]) + for node := range g.Nodes { + if len(g.EdgesTo[node]) == 0 { + orphans.Insert(node) + } + } + + loopWalk(out, g, 0) + for _, orphan := range maps.SortedKeys(orphans) { + loopWalk(out, g, orphan) + } +} + +func loopWalk(out io.Writer, scanData Graph, stack ...btrfsvol.LogicalAddr) { + for _, kp := range scanData.EdgesFrom[stack[len(stack)-1]] { + childStack := append(stack, kp.ToNode) + if slices.Contains(kp.ToNode, stack) { + loopRender(out, scanData, childStack...) + } else { + loopWalk(out, scanData, childStack...) + } + } +} + +func nodeRender(scanData Graph, node btrfsvol.LogicalAddr) []string { + if node == 0 { + return []string{"root"} + } else if nodeData, ok := scanData.Nodes[node]; ok { + return []string{ + fmt.Sprintf("{addr: %v,", node), + fmt.Sprintf(" level: %v,", nodeData.Level), + fmt.Sprintf(" gen: %v,", nodeData.Generation), + fmt.Sprintf(" num_items: %v,", nodeData.NumItems), + fmt.Sprintf(" min_item: {%d,%v,%d},", + nodeData.MinItem.ObjectID, + nodeData.MinItem.ItemType, + nodeData.MinItem.Offset), + fmt.Sprintf(" max_item: {%d,%v,%d}}", + nodeData.MaxItem.ObjectID, + nodeData.MaxItem.ItemType, + nodeData.MaxItem.Offset), + } + } else if nodeErr, ok := scanData.BadNodes[node]; ok { + return []string{ + fmt.Sprintf("{addr:%v,", node), + fmt.Sprintf(" err:%q}", nodeErr.Error()), + } + } else { + panic("should not happen") + } +} + +func edgeRender(scanData Graph, kp Edge) []string { + a := fmt.Sprintf("[%d]={", kp.FromItem) + b := strings.Repeat(" ", len(a)) + ret := []string{ + a + fmt.Sprintf("ToNode: %v,", kp.ToNode), + b + fmt.Sprintf("ToLevel: %v,", kp.ToLevel), + b + fmt.Sprintf("ToGen: %v,", kp.ToGeneration), + b + fmt.Sprintf("ToKey: {%d,%v,%d}}", + kp.ToKey.ObjectID, + kp.ToKey.ItemType, + kp.ToKey.Offset), + } + + var err error + if toNode, ok := scanData.Nodes[kp.ToNode]; !ok { + err = scanData.BadNodes[kp.ToNode] + } else { + err = checkNodeExpectations(kp, toNode) + } + if err != nil { + c := strings.Repeat(" ", len(a)-1) + ret = append(ret, + c+"^", + c+"`-err="+strings.ReplaceAll(err.Error(), "\n", "\n"+c+" "), + ) + } + return ret +} + +func loopRender(out io.Writer, scanData Graph, stack ...btrfsvol.LogicalAddr) { + var lines []string + add := func(suffixes []string) { + curLen := 0 + for _, line := range lines { + if len(line) > curLen { + curLen = len(line) + } + } + for i, suffix := range suffixes { + if len(lines) <= i { + lines = append(lines, "") + } + if len(lines[i]) < curLen { + if i == 0 { + lines[i] += strings.Repeat("-", curLen-len(lines[i])-1) + ">" + } else { + lines[i] += strings.Repeat(" ", curLen-len(lines[i])) + } + } + lines[i] += suffix + } + } + + for i, node := range stack { + if i > 0 { + for _, kp := range scanData.EdgesTo[node] { + if kp.FromNode == stack[i-1] { + add(edgeRender(scanData, *kp)) + break + } + } + } + add(nodeRender(scanData, node)) + } + + fmt.Fprintln(out, "loop:") + for _, line := range lines { + fmt.Fprintln(out, " "+line) + } +} + +func checkNodeExpectations(kp Edge, toNode Node) error { + var errs derror.MultiError + if toNode.Level != kp.ToLevel { + errs = append(errs, fmt.Errorf("kp.level=%v != node.level=%v", + kp.ToLevel, toNode.Level)) + } + if toNode.Generation != kp.ToGeneration { + errs = append(errs, fmt.Errorf("kp.generation=%v != node.generation=%v", + kp.ToGeneration, toNode.Generation)) + } + if toNode.NumItems == 0 { + errs = append(errs, fmt.Errorf("node.num_items=0")) + } else if kp.ToKey != (btrfsprim.Key{}) && toNode.MinItem != kp.ToKey { + errs = append(errs, fmt.Errorf("kp.key=%v != node.items[0].key=%v", + kp.ToKey, toNode.MinItem)) + } + if len(errs) > 0 { + return errs + } + return nil +} -- cgit v1.2.3-54-g00ecf