implement btree lookup

1 files changed, 11 insertions, 0 deletions

diff --git a/pkg/btrfs/internal/misc.go b/pkg/btrfs/internal/misc.go
index 2a98464..3dc77d6 100644
--- a/pkg/btrfs/internal/misc.go
+++ b/pkg/btrfs/internal/misc.go
@@ -4,6 +4,7 @@ import (
 	"time"
 
 	"lukeshu.com/btrfs-tools/pkg/binstruct"
+	"lukeshu.com/btrfs-tools/pkg/util"
 )
 
 type Generation uint64
@@ -15,6 +16,16 @@ type Key struct {
 	binstruct.End `bin:"off=0x11"`
 }
 
+func (a Key) Cmp(b Key) int {
+	if d := util.CmpUint(a.ObjectID, b.ObjectID); d != 0 {
+		return d
+	}
+	if d := util.CmpUint(a.ItemType, b.ItemType); d != 0 {
+		return d
+	}
+	return util.CmpUint(a.Offset, b.Offset)
+}
+
 type Time struct {
 	Sec           int64  `bin:"off=0x0, siz=0x8"` // Number of seconds since 1970-01-01T00:00:00Z.
 	NSec          uint32 `bin:"off=0x8, siz=0x4"` // Number of nanoseconds since the beginning of the second.