Add golang ci lint to CI (syndtr#350)

.golangci.yml

@@ -0,0 +1,11 @@
+linters-settings:
+  gocritic:
+    disabled-checks:
+      - ifElseChain
+      - elseif
+
+linters:
+  enable:
+    - gofmt
+    - gocritic
+    - unconvert

.travis.yml

@@ -1,19 +1,15 @@
 language: go
 
+before_install:
+  - curl -sSfL https://raw.githubusercontent.com/golangci/golangci-lint/master/install.sh | sh -s -- -b $(go env GOPATH)/bin v1.46.2
+
 go:
   - 1.14.x
   - 1.18.x
   - tip
 
 script:
-  - |
-    (set -e
-    if [ "$TRAVIS_GO_VERSION" != "tip" ]; then 
-      echo "executing go vet for go verion $TRAVIS_GO_VERSION"
-      go vet ./...
-    else
-      echo "skipping go vet for go verion $TRAVIS_GO_VERSION"
-    fi
-    )
+  - go vet ./...
+  - golangci-lint run
   - go test -short -timeout 1h ./...
   - go test -timeout 30m -race -run "TestDB_(Concurrent|GoleveldbIssue74)" ./leveldb

go.sum

@@ -93,6 +93,7 @@ golang.org/x/text v0.3.7 h1:olpwvP2KacW1ZWvsR7uQhoyTYvKAupfQrRGBFM352Gk=
 golang.org/x/text v0.3.7/go.mod h1:u+2+/6zg+i71rQMx5EYifcz6MCKuco9NR6JIITiCfzQ=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
+golang.org/x/tools v0.0.0-20201224043029-2b0845dc783e h1:4nW4NLDYnU28ojHaHO8OVxFHk/aQ33U01a9cjED+pzE=
 golang.org/x/tools v0.0.0-20201224043029-2b0845dc783e/go.mod h1:emZCQorbCU4vsT4fOWvOPXz4eW1wZW4PmDk9uLelYpA=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=

leveldb/batch.go

@@ -33,7 +33,6 @@ func newErrBatchCorrupted(reason string) error {
 const (
 	batchHeaderLen = 8 + 4
 	batchGrowLimit = 3000
-	batchBufioSize = 16
 )
 
 // BatchReplay wraps basic batch operations.
@@ -59,10 +58,6 @@ func (index batchIndex) v(data []byte) []byte {
 	return nil
 }
 
-func (index batchIndex) kv(data []byte) (key, value []byte) {
-	return index.k(data), index.v(data)
-}
-
 // Batch is a write batch.
 type Batch struct {
 	data  []byte
@@ -233,17 +228,6 @@ func (b *Batch) putMem(seq uint64, mdb *memdb.DB) error {
 	return nil
 }
 
-func (b *Batch) revertMem(seq uint64, mdb *memdb.DB) error {
-	var ik []byte
-	for i, index := range b.index {
-		ik = makeInternalKey(ik, index.k(b.data), seq+uint64(i), index.keyType)
-		if err := mdb.Delete(ik); err != nil {
-			return err
-		}
-	}
-	return nil
-}
-
 func newBatch() interface{} {
 	return &Batch{}
 }

leveldb/batch_test.go

@@ -168,7 +168,7 @@ func benchmarkBatchWrite(b *testing.B, config *BatchConfig) {
 		vals = append(vals, randomString(r, 100))
 	}
 	b.ResetTimer()
-	for round := 0; round < b.N; round += 1 {
+	for round := 0; round < b.N; round++ {
 		batch := MakeBatchWithConfig(config)
 		for i := 0; i < len(keys); i++ {
 			batch.Put(keys[i], vals[i])

leveldb/corrupt_test.go

@@ -164,18 +164,6 @@ func (h *dbCorruptHarness) corrupt(ft storage.FileType, fi, offset, n int) {
 	w.Close()
 }
 
-func (h *dbCorruptHarness) removeAll(ft storage.FileType) {
-	fds, err := h.stor.List(ft)
-	if err != nil {
-		h.t.Fatal("get files: ", err)
-	}
-	for _, fd := range fds {
-		if err := h.stor.Remove(fd); err != nil {
-			h.t.Error("remove file: ", err)
-		}
-	}
-}
-
 func (h *dbCorruptHarness) forceRemoveAll(ft storage.FileType) {
 	fds, err := h.stor.List(ft)
 	if err != nil {

leveldb/db.go

@@ -142,15 +142,16 @@ func openDB(s *session) (*DB, error) {
 			}
 			return nil, err
 		}
-
 	}
 
 	// Doesn't need to be included in the wait group.
 	go db.compactionError()
 	go db.mpoolDrain()
 
 	if readOnly {
-		db.SetReadOnly()
+		if err := db.SetReadOnly(); err != nil {
+			return nil, err
+		}
 	} else {
 		db.closeW.Add(2)
 		go db.tCompaction()
@@ -312,9 +313,17 @@ func recoverTable(s *session, o *opt.Options) error {
 			return
 		}
 		defer func() {
-			writer.Close()
+			if cerr := writer.Close(); cerr != nil {
+				if err == nil {
+					err = cerr
+				} else {
+					err = fmt.Errorf("error recovering table (%v); error closing (%v)", err, cerr)
+				}
+			}
 			if err != nil {
-				s.stor.Remove(tmpFd)
+				if rerr := s.stor.Remove(tmpFd); rerr != nil {
+					err = fmt.Errorf("error recovering table (%v); error removing (%v)", err, rerr)
+				}
 				tmpFd = storage.FileDesc{}
 			}
 		}()
@@ -531,7 +540,8 @@ func (db *DB) recoverJournal() error {
 			if jr == nil {
 				jr = journal.NewReader(fr, dropper{db.s, fd}, strict, checksum)
 			} else {
-				jr.Reset(fr, dropper{db.s, fd}, strict, checksum)
+				// Ignore the error here
+				_ = jr.Reset(fr, dropper{db.s, fd}, strict, checksum)
 			}
 
 			// Flush memdb and remove obsolete journal file.
@@ -551,7 +561,10 @@ func (db *DB) recoverJournal() error {
 				}
 				rec.resetAddedTables()
 
-				db.s.stor.Remove(ofd)
+				if err := db.s.stor.Remove(ofd); err != nil {
+					fr.Close()
+					return err
+				}
 				ofd = storage.FileDesc{}
 			}
 
@@ -635,7 +648,9 @@ func (db *DB) recoverJournal() error {
 
 	// Remove the last obsolete journal file.
 	if !ofd.Zero() {
-		db.s.stor.Remove(ofd)
+		if err := db.s.stor.Remove(ofd); err != nil {
+			return err
+		}
 	}
 
 	return nil
@@ -689,7 +704,9 @@ func (db *DB) recoverJournalRO() error {
 			if jr == nil {
 				jr = journal.NewReader(fr, dropper{db.s, fd}, strict, checksum)
 			} else {
-				jr.Reset(fr, dropper{db.s, fd}, strict, checksum)
+				if err := jr.Reset(fr, dropper{db.s, fd}, strict, checksum); err != nil {
+					return err
+				}
 			}
 
 			// Replay journal to memdb.

leveldb/db_compaction.go

@@ -7,6 +7,7 @@
 package leveldb
 
 import (
+	"fmt"
 	"sync"
 	"sync/atomic"
 	"time"
@@ -350,11 +351,11 @@ func (db *DB) memCompaction() {
 }
 
 type tableCompactionBuilder struct {
-	db           *DB
-	s            *session
-	c            *compaction
-	rec          *sessionRecord
-	stat0, stat1 *cStatStaging
+	db    *DB
+	s     *session
+	c     *compaction
+	rec   *sessionRecord
+	stat1 *cStatStaging
 
 	snapHasLastUkey bool
 	snapLastUkey    []byte
@@ -415,14 +416,17 @@ func (b *tableCompactionBuilder) flush() error {
 	return nil
 }
 
-func (b *tableCompactionBuilder) cleanup() {
+func (b *tableCompactionBuilder) cleanup() error {
 	if b.tw != nil {
-		b.tw.drop()
+		if err := b.tw.drop(); err != nil {
+			return err
+		}
 		b.tw = nil
 	}
+	return nil
 }
 
-func (b *tableCompactionBuilder) run(cnt *compactionTransactCounter) error {
+func (b *tableCompactionBuilder) run(cnt *compactionTransactCounter) (err error) {
 	snapResumed := b.snapIter > 0
 	hasLastUkey := b.snapHasLastUkey // The key might has zero length, so this is necessary.
 	lastUkey := append([]byte(nil), b.snapLastUkey...)
@@ -432,7 +436,15 @@ func (b *tableCompactionBuilder) run(cnt *compactionTransactCounter) error {
 	// Restore compaction state.
 	b.c.restore()
 
-	defer b.cleanup()
+	defer func() {
+		if cerr := b.cleanup(); cerr != nil {
+			if err == nil {
+				err = cerr
+			} else {
+				err = fmt.Errorf("tableCompactionBuilder error: %v, cleanup error (%v)", err, cerr)
+			}
+		}
+	}()
 
 	b.stat1.startTimer()
 	defer b.stat1.stopTimer()
@@ -655,10 +667,7 @@ func (db *DB) tableNeedCompaction() bool {
 func (db *DB) resumeWrite() bool {
 	v := db.s.version()
 	defer v.release()
-	if v.tLen(0) < db.s.o.GetWriteL0PauseTrigger() {
-		return true
-	}
-	return false
+	return v.tLen(0) < db.s.o.GetWriteL0PauseTrigger()
 }
 
 func (db *DB) pauseCompaction(ch chan<- struct{}) {
@@ -681,7 +690,7 @@ type cAuto struct {
 func (r cAuto) ack(err error) {
 	if r.ackC != nil {
 		defer func() {
-			recover()
+			_ = recover()
 		}()
 		r.ackC <- err
 	}
@@ -696,7 +705,7 @@ type cRange struct {
 func (r cRange) ack(err error) {
 	if r.ackC != nil {
 		defer func() {
-			recover()
+			_ = recover()
 		}()
 		r.ackC <- err
 	}

leveldb/db_iter.go

@@ -7,7 +7,6 @@
 package leveldb
 
 import (
-	"errors"
 	"math/rand"
 	"runtime"
 	"sync"
@@ -18,10 +17,6 @@ import (
 	"github.com/syndtr/goleveldb/leveldb/util"
 )
 
-var (
-	errInvalidInternalKey = errors.New("leveldb: Iterator: invalid internal key")
-)
-
 type memdbReleaser struct {
 	once sync.Once
 	m    *memDB

leveldb/db_state.go

@@ -137,8 +137,12 @@ func (db *DB) newMem(n int) (mem *memDB, err error) {
 	if db.journal == nil {
 		db.journal = journal.NewWriter(w)
 	} else {
-		db.journal.Reset(w)
-		db.journalWriter.Close()
+		if err := db.journal.Reset(w); err != nil {
+			return nil, err
+		}
+		if err := db.journalWriter.Close(); err != nil {
+			return nil, err
+		}
 		db.frozenJournalFd = db.journalFd
 	}
 	db.journalWriter = w
@@ -181,13 +185,6 @@ func (db *DB) getEffectiveMem() *memDB {
 	return db.mem
 }
 
-// Check whether we has frozen memdb.
-func (db *DB) hasFrozenMem() bool {
-	db.memMu.RLock()
-	defer db.memMu.RUnlock()
-	return db.frozenMem != nil
-}
-
 // Get frozen memdb.
 func (db *DB) getFrozenMem() *memDB {
 	db.memMu.RLock()