1 files changed, 15 insertions, 5 deletions

diff --git a/vendor/github.com/hashicorp/go-plugin/client.go b/vendor/github.com/hashicorp/go-plugin/client.go
index 679e10a..bc56559 100644
--- a/vendor/github.com/hashicorp/go-plugin/client.go
+++ b/vendor/github.com/hashicorp/go-plugin/client.go
@@ -87,6 +87,10 @@ type Client struct {
         // goroutines.
         clientWaitGroup sync.WaitGroup
 
+        // stderrWaitGroup is used to prevent the command's Wait() function from
+        // being called before we've finished reading from the stderr pipe.
+        stderrWaitGroup sync.WaitGroup
+
         // processKilled is used for testing only, to flag when the process was
         // forcefully killed.
         processKilled bool
@@ -590,6 +594,12 @@ func (c *Client) Start() (addr net.Addr, err error) {
         // Create a context for when we kill
         c.doneCtx, c.ctxCancel = context.WithCancel(context.Background())
 
+        // Start goroutine that logs the stderr
+        c.clientWaitGroup.Add(1)
+        c.stderrWaitGroup.Add(1)
+        // logStderr calls Done()
+        go c.logStderr(cmdStderr)
+
         c.clientWaitGroup.Add(1)
         go func() {
                 // ensure the context is cancelled when we're done
@@ -602,6 +612,10 @@ func (c *Client) Start() (addr net.Addr, err error) {
                 pid := c.process.Pid
                 path := cmd.Path
 
+                // wait to finish reading from stderr since the stderr pipe reader
+                // will be closed by the subsequent call to cmd.Wait().
+                c.stderrWaitGroup.Wait()
+
                 // Wait for the command to end.
                 err := cmd.Wait()
 
@@ -624,11 +638,6 @@ func (c *Client) Start() (addr net.Addr, err error) {
                 c.exited = true
         }()
 
-        // Start goroutine that logs the stderr
-        c.clientWaitGroup.Add(1)
-        // logStderr calls Done()
-        go c.logStderr(cmdStderr)
-
         // Start a goroutine that is going to be reading the lines
         // out of stdout
         linesCh := make(chan string)
@@ -936,6 +945,7 @@ var stdErrBufferSize = 64 * 1024
 
 func (c *Client) logStderr(r io.Reader) {
         defer c.clientWaitGroup.Done()
+        defer c.stderrWaitGroup.Done()
         l := c.logger.Named(filepath.Base(c.config.Cmd.Path))
 
         reader := bufio.NewReaderSize(r, stdErrBufferSize)