From 83212def27a030b9c145f8cc7494602a22040954 Mon Sep 17 00:00:00 2001
From: Gabriel Baraldi <baraldigabriel@gmail.com>
Date: Wed, 30 Aug 2023 15:03:30 -0300
Subject: [PATCH] Avoid potential race between read and upload_data

---
 src/Curl/Easy.jl | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/src/Curl/Easy.jl b/src/Curl/Easy.jl
index cf63f50..4855010 100644
--- a/src/Curl/Easy.jl
+++ b/src/Curl/Easy.jl
@@ -369,9 +369,11 @@ end
 # feed data to read_callback
 function upload_data(easy::Easy, input::IO)
     while true
-        data = eof(input) ? nothing : readavailable(input)
-        easy.input === nothing && break
-        easy.input = data
+        if easy.input === nothing || isempty(easy.input)
+            data = eof(input) ? nothing : readavailable(input)
+            easy.input === nothing && break
+            easy.input = data
+        end
         curl_easy_pause(easy.handle, Curl.CURLPAUSE_CONT)
         wait(easy.ready)
         easy.input === nothing && break