Expose latest opts properties (#82)

backup_test.go

@@ -1,7 +1,6 @@
 package grocksdb
 
 import (
-	"runtime"
 	"testing"
 
 	"github.com/stretchr/testify/require"
@@ -112,15 +111,7 @@ func TestBackupEngine(t *testing.T) {
 		// try to reopen restored db
 		backupDB, err := OpenDb(db.opts, dir)
 		require.Nil(t, err)
-
-		o, _ := LoadLatestOptions(dir, NewMemEnv(), true, NewLRUCache(1))
-		runtime.GC()
-		if o != nil {
-			o.Destroy()
-		}
-
-		_, err = LoadLatestOptions("", nil, true, nil)
-		require.Error(t, err)
+		defer backupDB.Close()
 
 		r := NewDefaultReadOptions()
 		defer r.Destroy()

comparator.go

@@ -4,16 +4,14 @@ package grocksdb
 // #include "grocksdb.h"
 import "C"
 
-import (
-	"bytes"
-)
-
 // Comparing functor.
 //
 // Three-way comparison. Returns value:
-//   < 0 iff "a" < "b",
-//   == 0 iff "a" == "b",
-//   > 0 iff "a" > "b"
+//
+//	< 0 iff "a" < "b",
+//	== 0 iff "a" == "b",
+//	> 0 iff "a" > "b"
+//
 // Note that Compare(a, b) also compares timestamp if timestamp size is
 // non-zero. For the same user key with different timestamps, larger (newer)
 // timestamp comes first.
@@ -22,9 +20,10 @@ type Comparing = func(a, b []byte) int
 // ComparingWithoutTimestamp functor.
 //
 // Three-way comparison. Returns value:
-//   < 0 if "a" < "b",
-//   == 0 if "a" == "b",
-//   > 0 if "a" > "b"
+//
+//	< 0 if "a" < "b",
+//	== 0 if "a" == "b",
+//	> 0 if "a" > "b"
 type ComparingWithoutTimestamp = func(a []byte, aHasTs bool, b []byte, bHasTs bool) int
 
 // NewComparator creates a Comparator object which contains native c-comparator pointer.
@@ -115,12 +114,3 @@ func gorocksdb_comparator_compare_without_ts(idx int, cKeyA *C.char, cKeyALen C.
 func gorocksdb_comparator_name(idx int) *C.char {
 	return comperators.Get(idx).(comperatorWrapper).name
 }
-
-// for testing purpose only
-type testBytesReverseComparator struct{}
-
-func (cmp *testBytesReverseComparator) Name() string { return "grocksdb.bytes-reverse" }
-func (cmp *testBytesReverseComparator) Compare(a, b []byte) int {
-	return bytes.Compare(a, b) * -1
-}
-func (cmp *testBytesReverseComparator) Destroy() {}

db_test.go

@@ -2,6 +2,7 @@ package grocksdb
 
 import (
 	"os"
+	"runtime"
 	"strconv"
 	"testing"
 
@@ -282,6 +283,36 @@ func TestDBMultiGet(t *testing.T) {
 	require.EqualValues(t, values[3].Data(), givenVal3)
 }
 
+func TestLoadLatestOpts(t *testing.T) {
+	dir := t.TempDir()
+
+	opts := NewDefaultOptions()
+	defer opts.Destroy()
+
+	opts.SetCreateIfMissing(true)
+	for i := 0; i < 100; i++ {
+		opts.SetEnv(NewDefaultEnv())
+	}
+
+	db, err := OpenDb(opts, dir)
+	require.NoError(t, err)
+	_, err = db.CreateColumnFamily(opts, "abc")
+	require.NoError(t, err)
+	require.NoError(t, db.Flush(NewDefaultFlushOptions()))
+	db.Close()
+
+	o, err := LoadLatestOptions(dir, NewDefaultEnv(), true, NewLRUCache(1))
+	runtime.GC()
+	require.NoError(t, err)
+	require.NotEmpty(t, o.ColumnFamilyNames())
+	require.NotEmpty(t, o.ColumnFamilyOpts())
+	o.Destroy()
+	runtime.GC()
+
+	_, err = LoadLatestOptions("", nil, true, nil)
+	require.Error(t, err)
+}
+
 func TestDBGetApproximateSizes(t *testing.T) {
 	db := newTestDB(t, nil)
 	defer db.Close()

options.go

@@ -90,7 +90,7 @@ const (
 // Options represent all of the available options when opening a database with Open.
 type Options struct {
 	c   *C.rocksdb_options_t
-	env *Env
+	env *C.rocksdb_env_t
 
 	// Hold references for GC.
 	bbto *BlockBasedTableOptions
@@ -306,13 +306,16 @@ func (opts *Options) SetDBPaths(dbpaths []*DBPath) {
 // SetEnv sets the specified object to interact with the environment,
 // e.g. to read/write files, schedule background work, etc.
 //
-// Note: move semantic. Don't use env after calling this function
+// NOTE: move semantic. Don't use env after calling this function
 func (opts *Options) SetEnv(env *Env) {
 	if opts.env != nil {
-		opts.env.Destroy()
+		C.rocksdb_env_destroy(opts.env)
 	}
-	opts.env = env
+
 	C.rocksdb_options_set_env(opts.c, env.c)
+	opts.env = env.c
+
+	env.c = nil
 }
 
 // SetInfoLogLevel sets the info log level.
@@ -2421,9 +2424,9 @@ func (opts *Options) Destroy() {
 	opts.cmo = nil
 
 	if opts.env != nil {
-		opts.env.Destroy()
+		C.rocksdb_env_destroy(opts.env)
+		opts.env = nil
 	}
-	opts.env = nil
 
 	opts.bbto = nil
 }
@@ -2491,7 +2494,18 @@ func LoadLatestOptions(path string, env *Env, ignoreUnknownOpts bool, cache *Cac
 	return
 }
 
+// ColumnFamilyNames gets column family names.
+func (l *LatestOptions) ColumnFamilyNames() []string {
+	return l.cfNames
+}
+
+// ColumnFamilyOpts returns corresponding options of column families.
+func (l *LatestOptions) ColumnFamilyOpts() []Options {
+	return l.cfOptions
+}
+
 // Destroy release underlying db_options, column_family_names, and column_family_options.
 func (l *LatestOptions) Destroy() {
 	C.rocksdb_load_latest_options_destroy(l.opts.c, l.cfNames_, l.cfOptions_, C.size_t(len(l.cfNames)))
+	l.opts.c = nil
 }