SFTPStream: fix error handling in fastGet/fastPut

Author: mscdex

lib/sftp.js

@@ -971,11 +971,17 @@ function fastXfer(src, dst, srcPath, dstPath, opts, cb) {
       pdst = 0,
       reads = 0,
       total = 0,
+      hadError = false,
       srcHandle,
       dstHandle,
       readbuf = new Buffer(chunkSize * concurrency);
 
   function onerror(err) {
+    if (hadError)
+      return;
+
+    hadError = true;
+
     var left = 0,
         cbfinal;
 
@@ -984,13 +990,13 @@ function fastXfer(src, dst, srcPath, dstPath, opts, cb) {
         if (--left === 0)
           cb(err);
       };
-      if (srcHandle)
+      if (srcHandle && (src === fs || src.writable))
         ++left;
-      if (dstHandle)
+      if (dstHandle && (dst === fs || dst.writable))
         ++left;
-      if (srcHandle)
+      if (srcHandle && (src === fs || src.writable))
         src.close(srcHandle, cbfinal);
-      if (dstHandle)
+      if (dstHandle && (dst === fs || dst.writable))
         dst.close(dstHandle, cbfinal);
     } else
       cb(err);