optional path to switch to callback

Author: azkrishpy

include/aws/crt/io/Stream.h

@@ -10,7 +10,7 @@
 #include <aws/io/async_stream.h>
 #include <aws/io/stream.h>
 
-#include <future>
+#include <functional>
 
 namespace Aws
 {
@@ -226,9 +226,9 @@ namespace Aws
 
                 /**
                  * Asynchronously read into buffer.
-                 * @return future<bool> - true on success (including EOF/no data available), false on error
+                 * Call onComplete(true) on success (including EOF), or onComplete(false) on error.
                  */
-                virtual std::future<bool> ReadImpl(ByteBuf &buffer) noexcept = 0;
+                virtual void ReadImpl(ByteBuf &buffer, std::function<void(bool)> onComplete) noexcept = 0;
 
               private:
                 static void s_Destroy(aws_async_input_stream *stream);

source/io/Stream.cpp

@@ -6,7 +6,6 @@
 #include <aws/crt/StlAllocator.h>
 #include <aws/crt/io/Stream.h>
 #include <iostream>
-#include <thread>
 
 #include <aws/io/future.h>
 #include <aws/io/stream.h>
@@ -250,17 +249,11 @@ namespace Aws
                 auto impl = static_cast<AsyncInputStream *>(stream->impl);
                 auto future = aws_future_bool_new(impl->m_allocator);
 
-                std::shared_future<bool> cppFuture = impl->ReadImpl(*dest).share();
-
                 aws_future_bool_acquire(future);
-                std::thread(
-                    [future, cppFuture]()
-                    {
-                        bool result = cppFuture.get();
-                        aws_future_bool_set_result(future, result);
-                        aws_future_bool_release(future);
-                    })
-                    .detach();
+                impl->ReadImpl(*dest, [future](bool result) {
+                    aws_future_bool_set_result(future, result);
+                    aws_future_bool_release(future);
+                });
 
                 return future;
             }