all: fix ineffectual assignments and remove uses of crypto.Sha3

go get github.com/gordonklaus/ineffassign
ineffassign .

swarm/api/api.go

@@ -140,8 +140,11 @@ func (self *Api) Put(content, contentType string) (string, error) {
 // to resolve path to content using dpa retrieve
 // it returns a section reader, mimeType, status and an error
 func (self *Api) Get(uri string, nameresolver bool) (reader storage.LazySectionReader, mimeType string, status int, err error) {
-
 	key, _, path, err := self.parseAndResolve(uri, nameresolver)
+	if err != nil {
+		return nil, "", 500, fmt.Errorf("can't resolve: %v", err)
+	}
+
 	quitC := make(chan bool)
 	trie, err := loadManifest(self.dpa, key, quitC)
 	if err != nil {
@@ -166,6 +169,10 @@ func (self *Api) Get(uri string, nameresolver bool) (reader storage.LazySectionR
 
 func (self *Api) Modify(uri, contentHash, contentType string, nameresolver bool) (newRootHash string, err error) {
 	root, _, path, err := self.parseAndResolve(uri, nameresolver)
+	if err != nil {
+		return "", fmt.Errorf("can't resolve: %v", err)
+	}
+
 	quitC := make(chan bool)
 	trie, err := loadManifest(self.dpa, root, quitC)
 	if err != nil {

swarm/api/config.go

@@ -69,7 +69,7 @@ func NewConfig(path string, contract common.Address, prvKey *ecdsa.PrivateKey, n
 	var data []byte
 	pubkey := crypto.FromECDSAPub(&prvKey.PublicKey)
 	pubkeyhex := common.ToHex(pubkey)
-	keyhex := crypto.Sha3Hash(pubkey).Hex()
+	keyhex := crypto.Keccak256Hash(pubkey).Hex()
 
 	self = &Config{
 		SyncParams:    network.NewSyncParams(dirpath),

swarm/api/filesystem.go

@@ -241,24 +241,7 @@ func (self *FileSystem) Download(bzzpath, localpath string) error {
 		}
 		go func(i int, entry *downloadListEntry) {
 			defer wg.Done()
-			f, err := os.Create(entry.path) // TODO: path separators
-			if err == nil {
-
-				reader := self.api.dpa.Retrieve(entry.key)
-				writer := bufio.NewWriter(f)
-				size, err := reader.Size(quitC)
-				if err == nil {
-					_, err = io.CopyN(writer, reader, size) // TODO: handle errors
-					err2 := writer.Flush()
-					if err == nil {
-						err = err2
-					}
-					err2 = f.Close()
-					if err == nil {
-						err = err2
-					}
-				}
-			}
+			err := retrieveToFile(quitC, self.api.dpa, entry.key, entry.path)
 			if err != nil {
 				select {
 				case errC <- err:
@@ -279,5 +262,24 @@ func (self *FileSystem) Download(bzzpath, localpath string) error {
 	case <-quitC:
 		return fmt.Errorf("aborted")
 	}
-
+}
+
+func retrieveToFile(quitC chan bool, dpa *storage.DPA, key storage.Key, path string) error {
+	f, err := os.Create(path) // TODO: path separators
+	if err != nil {
+		return err
+	}
+	reader := dpa.Retrieve(key)
+	writer := bufio.NewWriter(f)
+	size, err := reader.Size(quitC)
+	if err != nil {
+		return err
+	}
+	if _, err = io.CopyN(writer, reader, size); err != nil {
+		return err
+	}
+	if err := writer.Flush(); err != nil {
+		return err
+	}
+	return f.Close()
 }

swarm/api/filesystem_test.go

@@ -130,6 +130,7 @@ func TestApiDirUploadModify(t *testing.T) {
 		content = readPath(t, "testdata", "test0", "index.css")
 		resp = testGet(t, api, bzzhash+"/index.css")
 		exp = expResponse(content, "text/css", 0)
+		checkResponse(t, resp, exp)
 
 		_, _, _, err = api.Get(bzzhash, true)
 		if err == nil {