refactor: add devname into gpt.Partition, refactor probe package

Necessary refactoring to prepare for disk encryption implementation.
Talos part is going to be changed pretty much.

Signed-off-by: Artem Chernyshev <[email protected]>

.golangci.yml

@@ -1,6 +1,6 @@
 # THIS FILE WAS AUTOMATICALLY GENERATED, PLEASE DO NOT EDIT.
 #
-# Generated on 2020-09-04T03:46:02Z by kres latest.
+# Generated on 2021-01-21T16:47:42Z by kres latest.
 
 
 # options for analysis running
@@ -125,6 +125,9 @@ linters:
     - gomnd
     - goerr113
     - nestif
+    - wrapcheck
+    - paralleltest
+    - exhaustivestruct
   disable-all: false
   fast: false
 

Dockerfile

@@ -1,8 +1,8 @@
-# syntax = docker/dockerfile-upstream:1.1.7-experimental
+# syntax = docker/dockerfile-upstream:1.2.0-labs
 
 # THIS FILE WAS AUTOMATICALLY GENERATED, PLEASE DO NOT EDIT.
 #
-# Generated on 2020-10-23T19:30:04Z by kres e82c767-dirty.
+# Generated on 2021-01-21T16:47:42Z by kres latest.
 
 ARG TOOLCHAIN
 
@@ -17,14 +17,14 @@ RUN markdownlint --ignore "**/node_modules/**" --ignore '**/hack/chglog/**' --ru
 
 # base toolchain image
 FROM ${TOOLCHAIN} AS toolchain
-RUN apk --update --no-cache add bash curl build-base
+RUN apk --update --no-cache add bash curl build-base dosfstools
 
 # build tools
 FROM toolchain AS tools
 ENV GO111MODULE on
 ENV CGO_ENABLED 0
 ENV GOPATH /go
-RUN curl -sfL https://install.goreleaser.com/github.com/golangci/golangci-lint.sh | bash -s -- -b /bin v1.30.0
+RUN curl -sfL https://install.goreleaser.com/github.com/golangci/golangci-lint.sh | bash -s -- -b /bin v1.33.0
 ARG GOFUMPT_VERSION
 RUN cd $(mktemp -d) \
 	&& go mod init tmp \

blockdevice/blockdevice.go

@@ -18,7 +18,7 @@ type OutOfSpaceError interface {
 
 // IsOutOfSpaceError checks if provided error is 'out of space'.
 func IsOutOfSpaceError(err error) bool {
-	_, ok := err.(OutOfSpaceError)
+	_, ok := err.(OutOfSpaceError) //nolint:errorlint
 
 	return ok
 }

blockdevice/blockdevice_darwin.go

@@ -63,3 +63,18 @@ func (bd *BlockDevice) Reset() error {
 func (bd *BlockDevice) Wipe() error {
 	return fmt.Errorf("not implemented")
 }
+
+// OpenPartition opens another blockdevice using a partition of this block device.
+func (bd *BlockDevice) OpenPartition(label string) (*BlockDevice, error) {
+	return nil, fmt.Errorf("not implemented")
+}
+
+// GetPartition returns partition by label if found.
+func (bd *BlockDevice) GetPartition(label string) (*gpt.Partition, error) {
+	return nil, fmt.Errorf("not implemented")
+}
+
+// PartPath returns partition path by label, verifies that partition exists.
+func (bd *BlockDevice) PartPath(label string) (string, error) {
+	return "", fmt.Errorf("not implemented")
+}

blockdevice/blockdevice_linux.go

@@ -264,3 +264,49 @@ func (bd *BlockDevice) Reset() error {
 
 	return g.Write()
 }
+
+// OpenPartition opens another blockdevice using a partition of this block device.
+func (bd *BlockDevice) OpenPartition(label string) (*BlockDevice, error) {
+	g, err := bd.PartitionTable()
+	if err != nil {
+		return nil, err
+	}
+
+	part := g.Partitions().FindByName(label)
+	if part == nil {
+		return nil, os.ErrNotExist
+	}
+
+	path, err := part.Path()
+	if err != nil {
+		return nil, err
+	}
+
+	return Open(path)
+}
+
+// GetPartition returns partition by label if found.
+func (bd *BlockDevice) GetPartition(label string) (*gpt.Partition, error) {
+	g, err := bd.PartitionTable()
+	if err != nil {
+		return nil, err
+	}
+
+	part := g.Partitions().FindByName(label)
+
+	if part == nil {
+		return nil, os.ErrNotExist
+	}
+
+	return part, nil
+}
+
+// PartPath returns partition path by label, verifies that partition exists.
+func (bd *BlockDevice) PartPath(label string) (string, error) {
+	part, err := bd.GetPartition(label)
+	if err != nil {
+		return "", err
+	}
+
+	return part.Path()
+}

blockdevice/blockdevice_test.go

@@ -4,7 +4,9 @@
 
 package blockdevice_test
 
-import "testing"
+import (
+	"testing"
+)
 
 func TestEmpty(t *testing.T) {
 	// added for accurate coverage estimation

blockdevice/filesystem/fs.go

@@ -4,9 +4,76 @@
 
 package filesystem
 
+import (
+	"encoding/binary"
+	"io"
+	"os"
+	"time"
+
+	"github.com/talos-systems/go-retry/retry"
+	"golang.org/x/sys/unix"
+
+	"github.com/talos-systems/go-blockdevice/blockdevice/filesystem/iso9660"
+	"github.com/talos-systems/go-blockdevice/blockdevice/filesystem/vfat"
+	"github.com/talos-systems/go-blockdevice/blockdevice/filesystem/xfs"
+)
+
 // SuperBlocker describes the requirements for file system super blocks.
 type SuperBlocker interface {
 	Is() bool
 	Offset() int64
 	Type() string
 }
+
+const (
+	// Unknown filesystem.
+	Unknown string = "unknown"
+)
+
+// Probe checks partition type.
+func Probe(path string) (sb SuperBlocker, err error) {
+	var f *os.File
+	// Sleep for up to 5s to wait for kernel to create the necessary device files.
+	// If we dont sleep this becomes racy in that the device file does not exist
+	// and it will fail to open.
+	err = retry.Constant(5*time.Second, retry.WithUnits((50 * time.Millisecond))).Retry(func() error {
+		if f, err = os.OpenFile(path, os.O_RDONLY|unix.O_CLOEXEC, os.ModeDevice); err != nil {
+			if os.IsNotExist(err) {
+				return retry.ExpectedError(err)
+			}
+
+			return retry.UnexpectedError(err)
+		}
+
+		return nil
+	})
+	if err != nil {
+		return nil, err
+	}
+
+	//nolint: errcheck
+	defer f.Close()
+
+	superblocks := []SuperBlocker{
+		&iso9660.SuperBlock{},
+		&vfat.SuperBlock{},
+		&xfs.SuperBlock{},
+	}
+
+	for _, sb := range superblocks {
+		if _, err = f.Seek(sb.Offset(), io.SeekStart); err != nil {
+			return nil, err
+		}
+
+		err = binary.Read(f, binary.BigEndian, sb)
+		if err != nil {
+			return nil, err
+		}
+
+		if sb.Is() {
+			return sb, nil
+		}
+	}
+
+	return nil, nil
+}

blockdevice/loopback/loopback.go

@@ -38,7 +38,7 @@ import (
 // syscalls will return an errno type (which implements error) for all calls,
 // including success (errno 0). We only care about non-zero errnos.
 func errnoIsErr(err error) error {
-	if err.(syscall.Errno) != 0 {
+	if err.(syscall.Errno) != 0 { //nolint:errorlint
 		return err
 	}
 

blockdevice/partition/gpt/gpt.go

@@ -73,7 +73,7 @@ func Open(f *os.File) (g *GPT, err error) {
 			f: f,
 			l: l,
 			h: h,
-			e: &Partitions{h: h},
+			e: &Partitions{h: h, devname: f.Name()},
 		}
 
 		return g, nil
@@ -120,7 +120,7 @@ func New(f *os.File, setters ...Option) (g *GPT, err error) {
 		f: f,
 		l: l,
 		h: h,
-		e: &Partitions{h: h},
+		e: &Partitions{h: h, devname: f.Name()},
 	}
 
 	return g, nil
@@ -277,6 +277,7 @@ func (g *GPT) InsertAt(idx int, size uint64, setters ...PartitionOption) (*Parti
 		LastLBA:    end,
 		Attributes: opts.Attibutes,
 		Name:       opts.Name,
+		devname:    g.e.devname,
 	}
 
 	g.e.p = append(g.e.p[:idx], append([]*Partition{partition}, g.e.p[idx:]...)...)