From 8be8127351396593af941395f59c42e136f3e698 Mon Sep 17 00:00:00 2001
From: Emmanuel Odeke <emm.odeke@gmail.com>
Date: Sun, 24 Sep 2017 20:00:42 -0600
Subject: [PATCH 1/3] db: fix MemDB.Close

Fixes https://github.com/tendermint/tmlibs/issues/55

MemDB previously mistakenly set the actual DB pointer to nil
although that side effect is not visible to the outside world
since p is an identifier within the scope of just that function
call. However, @melekes and I had a discussion in which we
came to the conclusion that Close for an in-memory DB should
instead be a noop and not cause any data loss. See the
discussion on https://github.com/tendermint/tmlibs/pull/56.
---
 db/mem_db.go      |  8 +++++---
 db/mem_db_test.go | 20 ++++++++++++++++++++
 2 files changed, 25 insertions(+), 3 deletions(-)

diff --git a/db/mem_db.go b/db/mem_db.go
index db40227e..58e74895 100644
--- a/db/mem_db.go
+++ b/db/mem_db.go
@@ -52,9 +52,11 @@ func (db *MemDB) DeleteSync(key []byte) {
 }
 
 func (db *MemDB) Close() {
-	db.mtx.Lock()
-	defer db.mtx.Unlock()
-	db = nil
+	// Close is a noop since for an in-memory
+	// database, we don't have a destination
+	// to flush contents to nor do we want
+	// any data loss on invoking Close()
+	// See the discussion in https://github.com/tendermint/tmlibs/pull/56
 }
 
 func (db *MemDB) Print() {
diff --git a/db/mem_db_test.go b/db/mem_db_test.go
index a76e10dc..503e361f 100644
--- a/db/mem_db_test.go
+++ b/db/mem_db_test.go
@@ -4,6 +4,7 @@ import (
 	"testing"
 
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 )
 
 func TestMemDbIterator(t *testing.T) {
@@ -26,3 +27,22 @@ func TestMemDbIterator(t *testing.T) {
 	}
 	assert.Equal(t, i, len(db.db), "iterator didnt cover whole db")
 }
+
+func TestMemDBClose(t *testing.T) {
+	db := NewMemDB()
+	copyDB := func(orig map[string][]byte) map[string][]byte {
+		copy := make(map[string][]byte)
+		for k, v := range orig {
+			copy[k] = v
+		}
+		return copy
+	}
+	k, v := []byte("foo"), []byte("bar")
+	db.Set(k, v)
+	require.Equal(t, db.Get(k), v, "expecting a successful get")
+	copyBefore := copyDB(db.db)
+	db.Close()
+	require.Equal(t, db.Get(k), v, "Close is a noop, expecting a successful get")
+	copyAfter := copyDB(db.db)
+	require.Equal(t, copyBefore, copyAfter, "Close is a noop and shouldn't modify any internal data")
+}

From 0948343a6fd4efce07894c312d8e96c5f277c608 Mon Sep 17 00:00:00 2001
From: Ethan Buchman <ethan@coinculture.info>
Date: Mon, 2 Oct 2017 14:17:16 -0400
Subject: [PATCH 2/3] autofile: ensure file is open in Sync

---
 autofile/autofile.go | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/autofile/autofile.go b/autofile/autofile.go
index 5d6bc726..05fb0d67 100644
--- a/autofile/autofile.go
+++ b/autofile/autofile.go
@@ -103,6 +103,11 @@ func (af *AutoFile) Sync() error {
 	af.mtx.Lock()
 	defer af.mtx.Unlock()
 
+	if af.file == nil {
+		if err := af.openFile(); err != nil {
+			return err
+		}
+	}
 	return af.file.Sync()
 }
 

From e9c83b30058f60c8bf6810d52ab491712b9cedf7 Mon Sep 17 00:00:00 2001
From: Ethan Buchman <ethan@coinculture.info>
Date: Mon, 2 Oct 2017 23:26:45 -0400
Subject: [PATCH 3/3] version and changelog

---
 CHANGELOG.md       | 8 ++++++++
 version/version.go | 2 +-
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 4f5bd59c..e36a02d9 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,13 @@
 # Changelog
 
+## 0.3.2 (October 2, 2017)
+
+BUG FIXES:
+
+- [autofile] fix AutoFile.Sync() to open file if it's been closed
+- [db] fix MemDb.Close() to not empty the database (ie. its just a noop)
+
+
 ## 0.3.1 (September 22, 2017)
 
 BUG FIXES:
diff --git a/version/version.go b/version/version.go
index 6e030624..77580b5a 100644
--- a/version/version.go
+++ b/version/version.go
@@ -1,3 +1,3 @@
 package version
 
-const Version = "0.3.1"
+const Version = "0.3.2"