Fix race condition on httpSmartSubTransport

Signed-off-by: Paulo Gomes <paulo.gomes@weave.works>

pkg/git/libgit2/managed/http.go

@@ -217,6 +217,7 @@ type httpSmartSubtransportStream struct {
  sentRequest bool
  recvReply sync.WaitGroup
  httpError error
+ m sync.RWMutex
 }
 
 func newManagedHttpStream(owner *httpSmartSubtransport, req *http.Request, client *http.Client) *httpSmartSubtransportStream {
@@ -244,6 +245,8 @@ func (self *httpSmartSubtransportStream) Read(buf []byte) (int, error) {
 
  self.recvReply.Wait()
 
+ self.m.RLock()
+ defer self.m.RUnlock()
  if self.httpError != nil {
  return 0, self.httpError
  }
@@ -252,6 +255,8 @@ func (self *httpSmartSubtransportStream) Read(buf []byte) (int, error) {
 }
 
 func (self *httpSmartSubtransportStream) Write(buf []byte) (int, error) {
+ self.m.RLock()
+ defer self.m.RUnlock()
  if self.httpError != nil {
  return 0, self.httpError
  }
@@ -266,7 +271,11 @@ func (self *httpSmartSubtransportStream) Free() {
 
 func (self *httpSmartSubtransportStream) sendRequestBackground() {
  go func() {
- self.httpError = self.sendRequest()
+ err := self.sendRequest()
+
+ self.m.Lock()
+ self.httpError = err
+ self.m.Unlock()
  }()
  self.sentRequest = true
 }
@@ -299,33 +308,29 @@ func (self *httpSmartSubtransportStream) sendRequest() error {
  }
  }
 
- for {
- req := &http.Request{
- Method: self.req.Method,
- URL: self.req.URL,
- Header: self.req.Header,
- }
- if req.Method == "POST" {
- req.Body = self.reader
- req.ContentLength = -1
- }
-
- req.SetBasicAuth(userName, password)
- resp, err = self.client.Do(req)
- if err != nil {
- return err
- }
+ req := &http.Request{
+ Method: self.req.Method,
+ URL: self.req.URL,
+ Header: self.req.Header,
+ }
+ if req.Method == "POST" {
+ req.Body = self.reader
+ req.ContentLength = -1
+ }
 
- if resp.StatusCode == http.StatusOK {
- break
- }
+ req.SetBasicAuth(userName, password)
+ resp, err = self.client.Do(req)
+ if err != nil {
+ return err
+ }
 
- io.Copy(ioutil.Discard, resp.Body)
- resp.Body.Close()
- return fmt.Errorf("Unhandled HTTP error %s", resp.Status)
+ if resp.StatusCode == http.StatusOK {
+ self.resp = resp
+ self.sentRequest = true
+ return nil
  }
 
- self.sentRequest = true
- self.resp = resp
- return nil
+ io.Copy(ioutil.Discard, resp.Body)
+ defer resp.Body.Close()
+ return fmt.Errorf("Unhandled HTTP error %s", resp.Status)
 }