diff options
| -rw-r--r-- | pkg/btrfs/Makefile | 9 | ||||
| -rw-r--r-- | pkg/btrfs/btrfsitem/items.go | 21 | ||||
| -rw-r--r-- | pkg/btrfs/btrfsitem/items_gen.go | 21 | ||||
| -rw-r--r-- | pkg/btrfs/io2_fs.go | 14 | ||||
| -rw-r--r-- | pkg/btrfs/types_btree.go | 11 |
5 files changed, 62 insertions, 14 deletions
diff --git a/pkg/btrfs/Makefile b/pkg/btrfs/Makefile index fc6e9fd..b29e033 100644 --- a/pkg/btrfs/Makefile +++ b/pkg/btrfs/Makefile @@ -9,10 +9,17 @@ files += btrfsitem/items.txt btrfsitem/items_gen.go: btrfsitem/items.txt $(MAKEFILE_LIST) { \ echo 'package $(@D)'; \ - echo 'import "lukeshu.com/btrfs-tools/pkg/btrfs/internal"'; \ + echo 'import ('; \ + echo '"reflect"'; \ + echo; \ + echo '"lukeshu.com/btrfs-tools/pkg/btrfs/internal"'; \ + echo ')'; \ echo 'const ('; \ sed -E 's,(.*)=(.*) (.*),\1_KEY=internal.\1_KEY,' $<; \ echo ')'; \ + echo 'var keytype2gotype = map[Type]reflect.Type{'; \ + sed -E 's|(.*)=(.*) (.*)|\1_KEY: reflect.TypeOf(\3{}),|' $<; \ + echo '}'; \ sed -E 's,(.*)=(.*) (.*),\3,' $< | LC_COLLATE=C sort -u | sed 's,.*,func (&) isItem() {},'; \ } | gofmt >$@ files += btrfsitem/items_gen.go diff --git a/pkg/btrfs/btrfsitem/items.go b/pkg/btrfs/btrfsitem/items.go index 51e6344..91b7029 100644 --- a/pkg/btrfs/btrfsitem/items.go +++ b/pkg/btrfs/btrfsitem/items.go @@ -1,6 +1,10 @@ package btrfsitem import ( + "fmt" + "reflect" + + "lukeshu.com/btrfs-tools/pkg/binstruct" "lukeshu.com/btrfs-tools/pkg/btrfs/internal" ) @@ -9,3 +13,20 @@ type Type = internal.ItemType type Item interface { isItem() } + +func UnmarshalItem(keytyp Type, dat []byte) (Item, error) { + gotyp, ok := keytype2gotype[keytyp] + if !ok { + return nil, fmt.Errorf("btrfsitem.UnmarshalItem: unknown item type: %v", keytyp) + } + retPtr := reflect.New(gotyp) + n, err := binstruct.Unmarshal(dat, retPtr.Interface()) + if err != nil { + return nil, fmt.Errorf("btrfsitem.UnmarshalItem: %w", err) + } + if n < len(dat) { + return nil, fmt.Errorf("btrfsitem.UnmarshalItem: left over data: got %d bytes but only consumed %d", + len(dat), n) + } + return retPtr.Elem().Interface().(Item), nil +} diff --git a/pkg/btrfs/btrfsitem/items_gen.go b/pkg/btrfs/btrfsitem/items_gen.go index 5234c96..40a0b53 100644 --- a/pkg/btrfs/btrfsitem/items_gen.go +++ b/pkg/btrfs/btrfsitem/items_gen.go @@ -1,6 +1,10 @@ package btrfsitem -import "lukeshu.com/btrfs-tools/pkg/btrfs/internal" +import ( + "reflect" + + "lukeshu.com/btrfs-tools/pkg/btrfs/internal" +) const ( CHUNK_ITEM_KEY = internal.CHUNK_ITEM_KEY @@ -17,6 +21,21 @@ const ( UUID_RECEIVED_SUBVOL_KEY = internal.UUID_RECEIVED_SUBVOL_KEY ) +var keytype2gotype = map[Type]reflect.Type{ + CHUNK_ITEM_KEY: reflect.TypeOf(Chunk{}), + DEV_ITEM_KEY: reflect.TypeOf(Dev{}), + DEV_EXTENT_KEY: reflect.TypeOf(DevExtent{}), + UNTYPED_KEY: reflect.TypeOf(Empty{}), + QGROUP_RELATION_KEY: reflect.TypeOf(Empty{}), + INODE_ITEM_KEY: reflect.TypeOf(Inode{}), + INODE_REF_KEY: reflect.TypeOf(InodeRef{}), + ORPHAN_ITEM_KEY: reflect.TypeOf(Orphan{}), + PERSISTENT_ITEM_KEY: reflect.TypeOf(DevStats{}), + ROOT_ITEM_KEY: reflect.TypeOf(Root{}), + UUID_SUBVOL_KEY: reflect.TypeOf(UUIDMap{}), + UUID_RECEIVED_SUBVOL_KEY: reflect.TypeOf(UUIDMap{}), +} + func (Chunk) isItem() {} func (Dev) isItem() {} func (DevExtent) isItem() {} diff --git a/pkg/btrfs/io2_fs.go b/pkg/btrfs/io2_fs.go index bcf9777..b7752c7 100644 --- a/pkg/btrfs/io2_fs.go +++ b/pkg/btrfs/io2_fs.go @@ -5,7 +5,6 @@ import ( "fmt" "reflect" - "lukeshu.com/btrfs-tools/pkg/binstruct" "lukeshu.com/btrfs-tools/pkg/btrfs/btrfsitem" "lukeshu.com/btrfs-tools/pkg/util" ) @@ -123,17 +122,14 @@ func (fs *FS) Init() error { for _, chunk := range syschunks { fs.chunks = append(fs.chunks, chunk) } - if err := fs.WalkTree(sb.Data.ChunkTree, func(key Key, dat []byte) error { + if err := fs.WalkTree(sb.Data.ChunkTree, func(key Key, body btrfsitem.Item) error { if key.ItemType != btrfsitem.CHUNK_ITEM_KEY { return nil } - pair := SysChunk{ - Key: key, - } - if _, err := binstruct.Unmarshal(dat, &pair.Chunk); err != nil { - return err - } - fs.chunks = append(fs.chunks, pair) + fs.chunks = append(fs.chunks, SysChunk{ + Key: key, + Chunk: body.(btrfsitem.Chunk), + }) return nil }); err != nil { fs.initErr = err diff --git a/pkg/btrfs/types_btree.go b/pkg/btrfs/types_btree.go index 9b06e5e..cac5f9a 100644 --- a/pkg/btrfs/types_btree.go +++ b/pkg/btrfs/types_btree.go @@ -5,6 +5,7 @@ import ( "fmt" "lukeshu.com/btrfs-tools/pkg/binstruct" + "lukeshu.com/btrfs-tools/pkg/btrfs/btrfsitem" "lukeshu.com/btrfs-tools/pkg/util" ) @@ -87,7 +88,7 @@ type ItemHeader struct { type Item struct { Head ItemHeader - Body []byte + Body btrfsitem.Item } // MaxItems returns the maximum possible valid value of @@ -135,8 +136,12 @@ func (node *Node) UnmarshalBinary(nodeBuf []byte) (int, error) { return max(n, lastRead), fmt.Errorf("(leaf): item references byte %d, but node only has %d bytes", dataOff+dataSize, len(nodeBuf)) } + dataBuf := nodeBuf[dataOff : dataOff+dataSize] lastRead = max(lastRead, dataOff+dataSize) - item.Body = nodeBuf[dataOff : dataOff+dataSize] + item.Body, err = btrfsitem.UnmarshalItem(item.Head.Key.ItemType, dataBuf) + if err != nil { + return max(n, lastRead), fmt.Errorf("(leaf): item %d: %w", i, err) + } node.BodyLeaf = append(node.BodyLeaf, item) } @@ -210,7 +215,7 @@ func (fs *FS) ReadNode(addr LogicalAddr) (util.Ref[LogicalAddr, Node], error) { }, nil } -func (fs *FS) WalkTree(nodeAddr LogicalAddr, fn func(Key, []byte) error) error { +func (fs *FS) WalkTree(nodeAddr LogicalAddr, fn func(Key, btrfsitem.Item) error) error { if nodeAddr == 0 { return nil } |