From d29930c03193291a51fcae56f8cfde404018ff76 Mon Sep 17 00:00:00 2001
From: Kevin Atkinson <k@kevina.org>
Date: Fri, 8 Sep 2017 21:00:55 -0400
Subject: [PATCH] Eliminate Prefix field from MFS root, use MkdirOpts.

License: MIT
Signed-off-by: Kevin Atkinson <k@kevina.org>
---
 core/commands/files/files.go | 13 +++++--------
 core/coreunix/add.go         | 14 +++++++++++---
 mfs/mfs_test.go              |  4 ++--
 mfs/ops.go                   | 26 +++++++++++++++++---------
 mfs/system.go                |  3 ---
 5 files changed, 35 insertions(+), 25 deletions(-)

diff --git a/core/commands/files/files.go b/core/commands/files/files.go
index 645f24aa8..a39a0767b 100644
--- a/core/commands/files/files.go
+++ b/core/commands/files/files.go
@@ -746,15 +746,12 @@ Examples:
 			return
 		}
 		root := n.FilesRoot
-		if prefix != nil {
-			// FIXME: This is ugly and may not be correct either
-			// -- kevina
-			newRoot := *root
-			root = &newRoot
-			root.Prefix = prefix
-		}
 
-		err = mfs.Mkdir(root, dirtomake, dashp, flush)
+		err = mfs.Mkdir(root, dirtomake, mfs.MkdirOpts{
+			Mkparents: dashp,
+			Flush:     flush,
+			Prefix:    prefix,
+		})
 		if err != nil {
 			res.SetError(err, cmds.ErrNormal)
 			return
diff --git a/core/coreunix/add.go b/core/coreunix/add.go
index 9617fc46c..eca42b0a8 100644
--- a/core/coreunix/add.go
+++ b/core/coreunix/add.go
@@ -119,7 +119,6 @@ func (adder *Adder) mfsRoot() (*mfs.Root, error) {
 	rnode := unixfs.EmptyDirNode()
 	rnode.SetPrefix(adder.Prefix)
 	mr, err := mfs.NewRoot(adder.ctx, adder.dagService, rnode, nil)
-	mr.Prefix = adder.Prefix
 	if err != nil {
 		return nil, err
 	}
@@ -398,7 +397,12 @@ func (adder *Adder) addNode(node node.Node, path string) error {
 	}
 	dir := gopath.Dir(path)
 	if dir != "." {
-		if err := mfs.Mkdir(mr, dir, true, false); err != nil {
+		opts := mfs.MkdirOpts{
+			Mkparents: true,
+			Flush:     false,
+			Prefix:    adder.Prefix,
+		}
+		if err := mfs.Mkdir(mr, dir, opts); err != nil {
 			return err
 		}
 	}
@@ -496,7 +500,11 @@ func (adder *Adder) addDir(dir files.File) error {
 	if err != nil {
 		return err
 	}
-	err = mfs.Mkdir(mr, dir.FileName(), true, false)
+	err = mfs.Mkdir(mr, dir.FileName(), mfs.MkdirOpts{
+		Mkparents: true,
+		Flush:     false,
+		Prefix:    adder.Prefix,
+	})
 	if err != nil {
 		return err
 	}
diff --git a/mfs/mfs_test.go b/mfs/mfs_test.go
index 09e9de00d..bebfa8d30 100644
--- a/mfs/mfs_test.go
+++ b/mfs/mfs_test.go
@@ -735,7 +735,7 @@ func TestMfsHugeDir(t *testing.T) {
 	_, rt := setupRoot(ctx, t)
 
 	for i := 0; i < 10000; i++ {
-		err := Mkdir(rt, fmt.Sprintf("/dir%d", i), false, false)
+		err := Mkdir(rt, fmt.Sprintf("/dir%d", i), MkdirOpts{Mkparents: false, Flush: false})
 		if err != nil {
 			t.Fatal(err)
 		}
@@ -747,7 +747,7 @@ func TestMkdirP(t *testing.T) {
 	defer cancel()
 	_, rt := setupRoot(ctx, t)
 
-	err := Mkdir(rt, "/a/b/c/d/e/f", true, true)
+	err := Mkdir(rt, "/a/b/c/d/e/f", MkdirOpts{Mkparents: true, Flush: true})
 	if err != nil {
 		t.Fatal(err)
 	}
diff --git a/mfs/ops.go b/mfs/ops.go
index 5b72adcad..49ce398d4 100644
--- a/mfs/ops.go
+++ b/mfs/ops.go
@@ -9,6 +9,7 @@ import (
 
 	path "github.com/ipfs/go-ipfs/path"
 
+	cid "gx/ipfs/QmNp85zy9RLrQ5oQD4hPyS39ezrrXpcaa7R4Y9kxdWQLLQ/go-cid"
 	node "gx/ipfs/QmPN7cwmpcc4DWXb4KTB9dNAJgjuPY69h3npsMfhRrQL9c/go-ipld-format"
 )
 
@@ -97,9 +98,16 @@ func PutNode(r *Root, path string, nd node.Node) error {
 	return pdir.AddChild(filename, nd)
 }
 
+// MkdirOpts is used by Mkdir
+type MkdirOpts struct {
+	Mkparents bool
+	Flush     bool
+	Prefix    *cid.Prefix
+}
+
 // Mkdir creates a directory at 'path' under the directory 'd', creating
 // intermediary directories as needed if 'mkparents' is set to true
-func Mkdir(r *Root, pth string, mkparents bool, flush bool) error {
+func Mkdir(r *Root, pth string, opts MkdirOpts) error {
 	if pth == "" {
 		return fmt.Errorf("no path given to Mkdir")
 	}
@@ -115,7 +123,7 @@ func Mkdir(r *Root, pth string, mkparents bool, flush bool) error {
 
 	if len(parts) == 0 {
 		// this will only happen on 'mkdir /'
-		if mkparents {
+		if opts.Mkparents {
 			return nil
 		}
 		return fmt.Errorf("cannot create directory '/': Already exists")
@@ -124,13 +132,13 @@ func Mkdir(r *Root, pth string, mkparents bool, flush bool) error {
 	cur := r.GetValue().(*Directory)
 	for i, d := range parts[:len(parts)-1] {
 		fsn, err := cur.Child(d)
-		if err == os.ErrNotExist && mkparents {
+		if err == os.ErrNotExist && opts.Mkparents {
 			mkd, err := cur.Mkdir(d)
 			if err != nil {
 				return err
 			}
-			if r.Prefix != nil {
-				mkd.SetPrefix(r.Prefix)
+			if opts.Prefix != nil {
+				mkd.SetPrefix(opts.Prefix)
 			}
 			fsn = mkd
 		} else if err != nil {
@@ -146,15 +154,15 @@ func Mkdir(r *Root, pth string, mkparents bool, flush bool) error {
 
 	final, err := cur.Mkdir(parts[len(parts)-1])
 	if err != nil {
-		if !mkparents || err != os.ErrExist || final == nil {
+		if !opts.Mkparents || err != os.ErrExist || final == nil {
 			return err
 		}
 	}
-	if r.Prefix != nil {
-		final.SetPrefix(r.Prefix)
+	if opts.Prefix != nil {
+		final.SetPrefix(opts.Prefix)
 	}
 
-	if flush {
+	if opts.Flush {
 		err := final.Flush()
 		if err != nil {
 			return err
diff --git a/mfs/system.go b/mfs/system.go
index 0641704cf..fc5be0f6e 100644
--- a/mfs/system.go
+++ b/mfs/system.go
@@ -61,9 +61,6 @@ type Root struct {
 	dserv dag.DAGService
 
 	Type string
-
-	// Prefix to use for any children created
-	Prefix *cid.Prefix
 }
 
 type PubFunc func(context.Context, *cid.Cid) error