Merge branch 'full-wasm-support' of github.com:0xProject/goleveldb in…

…to full-wasm-support

browser-tests/main.go

@@ -11,7 +11,7 @@ import (
 func main() {
 	qunit.Module("LevelDB")
 	qunit.Test("set and get", func(assert qunit.QUnitAssert) {
-		dbPath := "leveldb-testing-" + uuid.New().String()
+		dbPath := "leveldb/testing/db-" + uuid.New().String()
 		db, err := leveldb.OpenFile(dbPath, nil)
 		assertNoError(assert, err, "could not open db")
 

browser_test.go

@@ -20,7 +20,7 @@ func TestInBrowser(t *testing.T) {
 	}
 
 	cmd = exec.Command("go", "build", "-o", "main.wasm", ".")
-	cmd.Env = append(os.Environ(), []string{"GOOS=js", "GOARCH=wasm"}...)
+	cmd.Env = append(os.Environ(), []string{"GOOS=js", "GOARCH=wasm", "GO111MODULE=on"}...)
 	cmd.Dir = "./browser-tests"
 	if output, err := cmd.CombinedOutput(); err != nil {
 		t.Log(string(output))

go.mod

@@ -1,8 +1,9 @@
 module github.com/syndtr/goleveldb
 
 require (
-	github.com/0xProject/qunit v0.0.0-20190730000255-81c18fdf7752 // indirect
+	github.com/0xProject/qunit v0.0.0-20190730000255-81c18fdf7752
 	github.com/golang/snappy v0.0.1
+	github.com/google/uuid v1.1.1
 	github.com/onsi/ginkgo v1.7.0
 	github.com/onsi/gomega v1.4.3
 )

go.sum

@@ -4,6 +4,8 @@ github.com/fsnotify/fsnotify v1.4.7/go.mod h1:jwhsz4b93w/PPRr/qN1Yymfu8t87LnFCMo
 github.com/golang/protobuf v1.2.0/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
 github.com/golang/snappy v0.0.1 h1:Qgr9rKW7uDUkrbSmQeiDsGa8SjGyCOGtuasMWwvp2P4=
 github.com/golang/snappy v0.0.1/go.mod h1:/XxbfmMg8lxefKM7IXC3fBNl/7bRcc72aCRzEWrmP2Q=
+github.com/google/uuid v1.1.1 h1:Gkbcsh/GbpXz7lPftLA3P6TYMwjCLYm83jiFQZF/3gY=
+github.com/google/uuid v1.1.1/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
 github.com/hpcloud/tail v1.0.0 h1:nfCOvKYfkgYP8hkirhJocXT2+zOD8yUNjXaWfTlyFKI=
 github.com/hpcloud/tail v1.0.0/go.mod h1:ab1qPbhIpdTxEkNHXyeSf5vhxWSCs/tWer42PpOxQnU=
 github.com/onsi/ginkgo v1.6.0/go.mod h1:lLunBs/Ym6LB5Z9jYTR76FiuTmxDTDusOGeTQH+WWjE=

leveldb/storage/file_storage_js.go

@@ -15,6 +15,7 @@ import (
 	"io"
 	"os"
 	"path/filepath"
+	"strings"
 	"sync"
 	"syscall"
 	"syscall/js"
@@ -140,6 +141,19 @@ func (f *browserFSFile) Write(b []byte) (n int, err error) {
 	// regardless of the encoding used. Encoding to hex seems like the most
 	// reliable way to do it.
 	rawBytesWritten := js.Global().Get("browserFS").Call("writeSync", f.fd, hex.EncodeToString(b), f.currOffset, "hex")
+
+	// Note: This a workaround for an issue that can cause data inconsistency
+	// (specifically an empty MANIFEST file). Normally fsync is not required on
+	// every write unless WriteOptions.Sync is set to true. However, we have
+	// observed that leveldb does not call fsync after creating a new MANIFEST
+	// file and deleting the old one. In BrowserFS, this means that the contents
+	// are never actually written to the file. On the next boot, leveldb will
+	// attempt to read from the manifest file and return an error because it is
+	// empty.
+	if err := f.Sync(); err != nil {
+		return 0, err
+	}
+
 	bytesWritten := rawBytesWritten.Int()
 	f.currOffset += int64(bytesWritten)
 	if bytesWritten != len(b) {
@@ -339,12 +353,30 @@ func browserFSMkdirAll(path string, perm os.FileMode) (err error) {
 			}
 		}
 	}()
-	// TODO(albrow): Add support for recursive mkdir. BrowserFS doesn't support it
-	// out of the box.
-	if len(filepath.SplitList(path)) > 1 {
-		return errors.New("recursive mkdir not supported in js/wasm")
+	// Note: mkdirAll is not supported by BrowserFS so we have to manually create
+	// each directory.
+	names := strings.Split(path, string(os.PathSeparator))
+	for i := range names {
+		partialPath := filepath.Join(names[:i+1]...)
+		if err := browserFSMkdir(partialPath, perm); err != nil {
+			if os.IsExist(err) {
+				// If the directory already exists, that's fine.
+				continue
+			}
+		}
 	}
-	js.Global().Get("browserFS").Call("mkdirSync", path, int(perm))
+	return nil
+}
+
+func browserFSMkdir(dir string, perm os.FileMode) (err error) {
+	defer func() {
+		if e := recover(); e != nil {
+			if jsErr, ok := e.(js.Error); ok {
+				err = convertJSError(jsErr)
+			}
+		}
+	}()
+	js.Global().Get("browserFS").Call("mkdirSync", dir, int(perm))
 	return nil
 }
 
@@ -429,6 +461,8 @@ func convertJSError(err js.Error) error {
 			return os.ErrNotExist
 		case "EISDIR":
 			return syscall.EISDIR
+		case "EEXIST":
+			return os.ErrExist
 			// TODO(albrow): Fill in more codes here.
 		}
 	}