From 36372dd3c8dc8d6333d751fb7d1939e25cc39a78 Mon Sep 17 00:00:00 2001
From: Aleksa Sarai <asarai@suse.de>
Date: Wed, 27 Jul 2016 22:03:43 +1000
Subject: [PATCH] mtree: remove use of dhCreator for iterators

Fix a bug in the parser that caused all iterators to have to handle the
/set and /unset semantics separately. In addition, provide a helper
function to correctly generate the merged set of keywords for a
particular entry.

Signed-off-by: Aleksa Sarai <asarai@suse.de>
---
 check.go | 45 +++++++++------------------------------------
 entry.go | 13 +++++++++++++
 parse.go |  1 +
 3 files changed, 23 insertions(+), 36 deletions(-)

diff --git a/check.go b/check.go
index 5586973..6a20848 100644
--- a/check.go
+++ b/check.go
@@ -32,7 +32,6 @@ func (f Failure) String() string {
 // the available keywords from the list and each entry in the hierarchy.
 // If keywords is nil, the check all present in the DirectoryHierarchy
 func Check(root string, dh *DirectoryHierarchy, keywords []string) (*Result, error) {
-	creator := dhCreator{DH: dh}
 	curDir, err := os.Getwd()
 	if err == nil {
 		defer os.Chdir(curDir)
@@ -41,16 +40,11 @@ func Check(root string, dh *DirectoryHierarchy, keywords []string) (*Result, err
 	if err := os.Chdir(root); err != nil {
 		return nil, err
 	}
-	sort.Sort(byPos(creator.DH.Entries))
+	sort.Sort(byPos(dh.Entries))
+
 	var result Result
-	for i, e := range creator.DH.Entries {
+	for _, e := range dh.Entries {
 		switch e.Type {
-		case SpecialType:
-			if e.Name == "/set" {
-				creator.curSet = &creator.DH.Entries[i]
-			} else if e.Name == "/unset" {
-				creator.curSet = nil
-			}
 		case RelativeType, FullType:
 			pathname, err := e.Path()
 			if err != nil {
@@ -61,12 +55,8 @@ func Check(root string, dh *DirectoryHierarchy, keywords []string) (*Result, err
 				return nil, err
 			}
 
-			var kvs KeyVals
-			if creator.curSet != nil {
-				kvs = MergeSet(creator.curSet.Keywords, e.Keywords)
-			} else {
-				kvs = NewKeyVals(e.Keywords)
-			}
+			kvs := e.AllKeys()
+
 			for _, kv := range kvs {
 				kw := kv.Keyword()
 				// 'tar_time' keyword evaluation wins against 'time' keyword evaluation
@@ -133,18 +123,11 @@ func TarCheck(tarDH, dh *DirectoryHierarchy, keywords []string) (*Result, error)
 		Type: CommentType,
 	}
 	curDir := tarRoot
-	creator := dhCreator{DH: dh}
-	sort.Sort(byPos(creator.DH.Entries))
+	sort.Sort(byPos(dh.Entries))
 
 	var outOfTree bool
-	for i, e := range creator.DH.Entries {
+	for _, e := range dh.Entries {
 		switch e.Type {
-		case SpecialType:
-			if e.Name == "/set" {
-				creator.curSet = &creator.DH.Entries[i]
-			} else if e.Name == "/unset" {
-				creator.curSet = nil
-			}
 		case RelativeType, FullType:
 			pathname, err := e.Path()
 			if err != nil {
@@ -166,20 +149,10 @@ func TarCheck(tarDH, dh *DirectoryHierarchy, keywords []string) (*Result, error)
 			}
 
 			// expected values from file hierarchy spec
-			var kvs KeyVals
-			if creator.curSet != nil {
-				kvs = MergeSet(creator.curSet.Keywords, e.Keywords)
-			} else {
-				kvs = NewKeyVals(e.Keywords)
-			}
+			kvs := e.AllKeys()
 
 			// actual
-			var tarkvs KeyVals
-			if tarEntry.Set != nil {
-				tarkvs = MergeSet(tarEntry.Set.Keywords, tarEntry.Keywords)
-			} else {
-				tarkvs = NewKeyVals(tarEntry.Keywords)
-			}
+			tarkvs := tarEntry.AllKeys()
 
 			for _, kv := range kvs {
 				// TODO: keep track of symlinks
diff --git a/entry.go b/entry.go
index 8273e8d..055e9a0 100644
--- a/entry.go
+++ b/entry.go
@@ -100,6 +100,19 @@ func (e Entry) String() string {
 	return fmt.Sprintf("    %s %s", e.Name, strings.Join(e.Keywords, " "))
 }
 
+// AllKeys returns the full set of KeyVals for the given entry, based on the
+// /set keys as well as the entry-local keys. Entry-local keys always take
+// precedence.
+func (e Entry) AllKeys() KeyVals {
+	var kv KeyVals
+	if e.Set != nil {
+		kv = MergeSet(e.Set.Keywords, e.Keywords)
+	} else {
+		kv = NewKeyVals(e.Keywords)
+	}
+	return kv
+}
+
 // EntryType are the formats of lines in an mtree spec file
 type EntryType int
 
diff --git a/parse.go b/parse.go
index 77987c6..9e1f9bb 100644
--- a/parse.go
+++ b/parse.go
@@ -93,6 +93,7 @@ func ParseSpec(r io.Reader) (*DirectoryHierarchy, error) {
 					}
 				}
 			}
+			e.Set = creator.curSet
 		default:
 			// TODO(vbatts) log a warning?
 			continue