go.mod: vendor in gitobj v1.4.0

Vendor in a new version of gitobj so that we can depend on it for
alternates support.

go.mod

@@ -2,7 +2,7 @@ module github.com/git-lfs/git-lfs
 
 require (
 	github.com/alexbrainman/sspi v0.0.0-20180125232955-4729b3d4d858
-	github.com/git-lfs/gitobj v1.3.1
+	github.com/git-lfs/gitobj v1.4.0
 	github.com/git-lfs/go-netrc v0.0.0-20180525200031-e0e9ca483a18
 	github.com/git-lfs/go-ntlm v0.0.0-20190307203151-c5056e7fa066
 	github.com/git-lfs/wildmatch v1.0.2

go.sum

@@ -2,8 +2,8 @@ github.com/alexbrainman/sspi v0.0.0-20180125232955-4729b3d4d858 h1:OZQyEhf4Bviyd
 github.com/alexbrainman/sspi v0.0.0-20180125232955-4729b3d4d858/go.mod h1:976q2ETgjT2snVCf2ZaBnyBbVoPERGjUz+0sofzEfro=
 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/git-lfs/gitobj v1.3.1 h1:Nni8wnRfvT3x91rDl3V397LjKOUoiaEK6vyIcA92aM8=
-github.com/git-lfs/gitobj v1.3.1/go.mod h1:EdPNGHVxXe1jTuNXzZT1+CdJCuASoDSLPQuvNOo9nGM=
+github.com/git-lfs/gitobj v1.4.0 h1:F7fKUUM/OTVu0ejnBA6x0trSYM8A9Zv7VGoBTsMmhHk=
+github.com/git-lfs/gitobj v1.4.0/go.mod h1:EdPNGHVxXe1jTuNXzZT1+CdJCuASoDSLPQuvNOo9nGM=
 github.com/git-lfs/go-netrc v0.0.0-20180525200031-e0e9ca483a18 h1:7Th0eBA4rT8WJNiM1vppjaIv9W5WJinhpbCJvRJxloI=
 github.com/git-lfs/go-netrc v0.0.0-20180525200031-e0e9ca483a18/go.mod h1:70O4NAtvWn1jW8V8V+OKrJJYcxDLTmIozfi2fmSz5SI=
 github.com/git-lfs/go-ntlm v0.0.0-20190307203151-c5056e7fa066 h1:j7JwIEwLNQ/kBdKpHO3U1jjMXIPjSq7eCFvQIF3e8Fs=

vendor/github.com/git-lfs/gitobj/backend.go

@@ -5,6 +5,9 @@ import (
 	"io"
 	"os"
 	"path"
+	"regexp"
+	"strconv"
+	"strings"
 
 	"github.com/git-lfs/gitobj/pack"
 	"github.com/git-lfs/gitobj/storage"
@@ -12,6 +15,14 @@ import (
 
 // NewFilesystemBackend initializes a new filesystem-based backend.
 func NewFilesystemBackend(root, tmp string) (storage.Backend, error) {
+	return NewFilesystemBackendWithAlternates(root, tmp, "")
+}
+
+// NewFilesystemBackendWithAlternates initializes a new filesystem-based
+// backend, optionally with additional alternates as specified in the
+// `alternates` variable. The syntax is that of the Git environment variable
+// GIT_ALTERNATE_OBJECT_DIRECTORIES.
+func NewFilesystemBackendWithAlternates(root, tmp, alternates string) (storage.Backend, error) {
 	fsobj := newFileStorer(root, tmp)
 	packs, err := pack.NewStorage(root)
 	if err != nil {
@@ -23,6 +34,11 @@ func NewFilesystemBackend(root, tmp string) (storage.Backend, error) {
 		return nil, err
 	}
 
+	storage, err = addAlternatesFromEnvironment(storage, alternates)
+	if err != nil {
+		return nil, err
+	}
+
 	return &filesystemBackend{
 		fs:       fsobj,
 		backends: storage,
@@ -45,12 +61,10 @@ func findAllBackends(mainLoose *fileStorer, mainPacked *pack.Storage, root strin
 
 	scanner := bufio.NewScanner(f)
 	for scanner.Scan() {
-		storage = append(storage, newFileStorer(scanner.Text(), ""))
-		pack, err := pack.NewStorage(scanner.Text())
+		storage, err = addAlternateDirectory(storage, scanner.Text())
 		if err != nil {
 			return nil, err
 		}
-		storage = append(storage, pack)
 	}
 
 	if err := scanner.Err(); err != nil {
@@ -60,6 +74,76 @@ func findAllBackends(mainLoose *fileStorer, mainPacked *pack.Storage, root strin
 	return storage, nil
 }
 
+func addAlternateDirectory(s []storage.Storage, dir string) ([]storage.Storage, error) {
+	s = append(s, newFileStorer(dir, ""))
+	pack, err := pack.NewStorage(dir)
+	if err != nil {
+		return s, err
+	}
+	s = append(s, pack)
+	return s, nil
+}
+
+func addAlternatesFromEnvironment(s []storage.Storage, env string) ([]storage.Storage, error) {
+	if len(env) == 0 {
+		return s, nil
+	}
+
+	for _, dir := range splitAlternateString(env, alternatesSeparator) {
+		var err error
+		s, err = addAlternateDirectory(s, dir)
+		if err != nil {
+			return nil, err
+		}
+	}
+	return s, nil
+}
+
+var (
+	octalEscape  = regexp.MustCompile("\\\\[0-7]{1,3}")
+	hexEscape    = regexp.MustCompile("\\\\x[0-9a-fA-F]{2}")
+	replacements = []struct {
+		olds string
+		news string
+	}{
+		{`\a`, "\a"},
+		{`\b`, "\b"},
+		{`\t`, "\t"},
+		{`\n`, "\n"},
+		{`\v`, "\v"},
+		{`\f`, "\f"},
+		{`\r`, "\r"},
+		{`\\`, "\\"},
+		{`\"`, "\""},
+		{`\'`, "'"},
+	}
+)
+
+func splitAlternateString(env string, separator string) []string {
+	dirs := strings.Split(env, separator)
+	for i, s := range dirs {
+		if !strings.HasPrefix(s, `"`) || !strings.HasSuffix(s, `"`) {
+			continue
+		}
+
+		// Strip leading and trailing quotation marks
+		s = s[1 : len(s)-1]
+		for _, repl := range replacements {
+			s = strings.Replace(s, repl.olds, repl.news, -1)
+		}
+		s = octalEscape.ReplaceAllStringFunc(s, func(inp string) string {
+			val, _ := strconv.ParseUint(inp[1:], 8, 64)
+			return string([]byte{byte(val)})
+		})
+		s = hexEscape.ReplaceAllStringFunc(s, func(inp string) string {
+			val, _ := strconv.ParseUint(inp[2:], 16, 64)
+			return string([]byte{byte(val)})
+		})
+		dirs[i] = s
+	}
+	return dirs
+}
+
 // NewMemoryBackend initializes a new memory-based backend.
 //
 // A value of "nil" is acceptable and indicates that no entries should be added

vendor/github.com/git-lfs/gitobj/backend_nix.go

@@ -0,0 +1,5 @@
+// +build !windows
+
+package gitobj
+
+const alternatesSeparator = ":"

vendor/github.com/git-lfs/gitobj/backend_windows.go

@@ -0,0 +1,5 @@
+// +build windows
+
+package gitobj
+
+const alternatesSeparator = ";"

vendor/github.com/git-lfs/gitobj/object_db.go

@@ -36,7 +36,16 @@ type ObjectDatabase struct {
 //
 //  /absolute/repo/path/.git/objects
 func FromFilesystem(root, tmp string) (*ObjectDatabase, error) {
-	b, err := NewFilesystemBackend(root, tmp)
+	return FromFilesystemWithAlternates(root, tmp, "")
+}
+
+// FromFilesystemWithAlternates constructs an *ObjectDatabase instance that is
+// backed by a directory on the filesystem, optionally with one or more
+// alternates. Specifically, this should point to:
+//
+//  /absolute/repo/path/.git/objects
+func FromFilesystemWithAlternates(root, tmp, alternates string) (*ObjectDatabase, error) {
+	b, err := NewFilesystemBackendWithAlternates(root, tmp, alternates)
 	if err != nil {
 		return nil, err
 	}

vendor/modules.txt

@@ -3,7 +3,7 @@ github.com/alexbrainman/sspi
 github.com/alexbrainman/sspi/ntlm
 # github.com/davecgh/go-spew v1.1.1
 github.com/davecgh/go-spew/spew
-# github.com/git-lfs/gitobj v1.3.1
+# github.com/git-lfs/gitobj v1.4.0
 github.com/git-lfs/gitobj
 github.com/git-lfs/gitobj/errors
 github.com/git-lfs/gitobj/pack