multi error

4 files changed, 50 insertions, 14 deletions

diff --git a/go.mod b/go.mod
index 9aa3e50..07ce874 100644
--- a/go.mod
+++ b/go.mod
@@ -3,13 +3,15 @@ module lukeshu.com/btrfs-tools
 go 1.18
 
 require (
-	github.com/davecgh/go-spew v1.1.0
+	github.com/datawire/dlib v1.3.0
+	github.com/davecgh/go-spew v1.1.1
 	github.com/stretchr/testify v1.7.1
 	golang.org/x/exp v0.0.0-20220518171630-0b5c67f07fdf
 	golang.org/x/text v0.3.7
 )
 
 require (
+	github.com/pkg/errors v0.9.1 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
 	gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c // indirect
 )
diff --git a/go.sum b/go.sum
index 8d735b5..5d6b3e0 100644
--- a/go.sum
+++ b/go.sum
@@ -1,15 +1,36 @@
-github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8=
+github.com/datawire/dlib v1.3.0 h1:KkmyXU1kwm3oPBk1ypR70YbcOlEXWzEbx5RE0iRXTGk=
+github.com/datawire/dlib v1.3.0/go.mod h1:NiGDmetmbkBvtznpWSx6C0vA0s0LK9aHna3LJDqjruk=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/konsorten/go-windows-terminal-sequences v1.0.3/go.mod h1:T0+1ngSBFLxvqU3pZ+m/2kptfBszLMUkC4ZK/EgS/cQ=
+github.com/kr/pretty v0.1.0 h1:L/CwN0zerZDmRFUapSPitk6f+Q3+0za1rQkzVuMiMFI=
+github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORNo=
+github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
+github.com/kr/text v0.1.0 h1:45sCR5RtlFHMR4UwH9sdQ5TC8v0qDQCHnXt+kaKSTVE=
+github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
+github.com/pkg/errors v0.9.1 h1:FEBLx1zS214owpjy7qsBeixbURkuhQAwrK5UwLGTwt4=
+github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/sirupsen/logrus v1.6.0/go.mod h1:7uNnSEd1DgxDLC74fIahvMZmmYsHGZGEOFrfsX/uA88=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
+github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/stretchr/testify v1.7.1 h1:5TQK59W5E3v0r2duFAb7P95B6hEeOyEnHRa8MjYSMTY=
 github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 golang.org/x/exp v0.0.0-20220518171630-0b5c67f07fdf h1:oXVg4h2qJDd9htKxb5SCpFBHLipW6hXmL3qpUixS2jw=
 golang.org/x/exp v0.0.0-20220518171630-0b5c67f07fdf/go.mod h1:yh0Ynu2b5ZUe3MQfp2nM0ecK7wsgouWTDN0FNeJuIys=
+golang.org/x/net v0.0.0-20210226172049-e18ecbb05110/go.mod h1:m0MpNAwzfU5UDzcl9v0D8zg8gWTRqZa9RBIspLL5mdg=
+golang.org/x/sys v0.0.0-20190422165155-953cdadca894/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
+golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/text v0.3.7 h1:olpwvP2KacW1ZWvsR7uQhoyTYvKAupfQrRGBFM352Gk=
 golang.org/x/text v0.3.7/go.mod h1:u+2+/6zg+i71rQMx5EYifcz6MCKuco9NR6JIITiCfzQ=
-gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
+golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15 h1:YR8cESwS4TdDjEe65xsg0ogRM/Nc3DYOhEAlW+xobZo=
+gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c h1:dUUwHk2QECo/6vqA44rthZ8ie2QXMNeKRTHCNY2nXvo=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
diff --git a/pkg/btrfs/btree.go b/pkg/btrfs/btree.go
index 9f38eee..cc68002 100644
--- a/pkg/btrfs/btree.go
+++ b/pkg/btrfs/btree.go
@@ -8,6 +8,8 @@ import (
 	"math"
 	"strings"
 
+	"github.com/datawire/dlib/derror"
+
 	"lukeshu.com/btrfs-tools/pkg/util"
 )
 
@@ -386,6 +388,10 @@ func (fs *FS) TreeLookup(treeRoot LogicalAddr, key Key) (Item, error) {
 	return fs.TreeSearch(treeRoot, key.Cmp)
 }
 
+// If some items are able to be read, but there is an error reading the full set, then it might
+// return *both* a list of items and an error.
+//
+// If no such item is found, an error that is io/fs.ErrNotExist is returned.
 func (fs *FS) TreeSearchAll(treeRoot LogicalAddr, fn func(Key) int) ([]Item, error) {
 	middlePath, middleNode, err := fs.treeSearch(treeRoot, fn)
 	if err != nil {
@@ -394,12 +400,12 @@ func (fs *FS) TreeSearchAll(treeRoot LogicalAddr, fn func(Key) int) ([]Item, err
 	middleItem := middleNode.Data.BodyLeaf[middlePath[len(middlePath)-1].ItemIdx]
 
 	var ret = []Item{middleItem}
-	i := 0
+	var errs derror.MultiError
 	for prevPath, prevNode := middlePath, middleNode; true; {
-		i--
 		prevPath, prevNode, err = fs.prev(prevPath, prevNode)
 		if err != nil {
-			return nil, err
+			errs = append(errs, err)
+			break
 		}
 		if prevPath == nil {
 			break
@@ -411,12 +417,11 @@ func (fs *FS) TreeSearchAll(treeRoot LogicalAddr, fn func(Key) int) ([]Item, err
 		ret = append(ret, prevItem)
 	}
 	util.ReverseSlice(ret)
-	i = 0
 	for nextPath, nextNode := middlePath, middleNode; true; {
-		i++
 		nextPath, nextNode, err = fs.next(nextPath, nextNode)
 		if err != nil {
-			return nil, err
+			errs = append(errs, err)
+			break
 		}
 		if nextPath == nil {
 			break
@@ -427,5 +432,8 @@ func (fs *FS) TreeSearchAll(treeRoot LogicalAddr, fn func(Key) int) ([]Item, err
 		}
 		ret = append(ret, nextItem)
 	}
-	return ret, nil
+	if errs != nil {
+		err = errs
+	}
+	return ret, err
 }
diff --git a/pkg/btrfs/io2_fs.go b/pkg/btrfs/io2_fs.go
index 33bfcbf..5129329 100644
--- a/pkg/btrfs/io2_fs.go
+++ b/pkg/btrfs/io2_fs.go
@@ -4,6 +4,8 @@ import (
 	"fmt"
 	"io"
 
+	"github.com/datawire/dlib/derror"
+
 	"lukeshu.com/btrfs-tools/pkg/btrfs/btrfsitem"
 	"lukeshu.com/btrfs-tools/pkg/btrfs/btrfsvol"
 	"lukeshu.com/btrfs-tools/pkg/util"
@@ -169,13 +171,16 @@ func (fs *FS) initDev(sb *util.Ref[PhysicalAddr, Superblock]) error {
 }
 
 func (fs *FS) Close() error {
-	var err error
+	var errs derror.MultiError
 	for _, dev := range fs.LV.PhysicalVolumes() {
-		if _err := dev.Close(); _err != nil && err == nil {
-			err = _err
+		if err := dev.Close(); err != nil && err == nil {
+			errs = append(errs, err)
 		}
 	}
-	return err
+	if errs != nil {
+		return errs
+	}
+	return nil
 }
 
 var _ io.Closer = (*FS)(nil)