Lower Boost_MINVERSION to 1.71.0 and add compatibility for older Boost versions

Author: aljazfrancic

external/boost/CMakeLists.txt

@@ -7,7 +7,7 @@ target_compile_definitions(boost_websocket INTERFACE BOOST_ALL_NO_LIB)
 # using only asio and beast
 # handle Boost dependencies here only if not already handled by parent project
 if (NOT TARGET Boost::beast)
-    set(Boost_MINVERSION "1.90.0")
+    set(Boost_MINVERSION "1.71.0")
     set(Boost_REQUIREDVERSION "1.90.0")
 
     set(Boost_USE_MULTITHREADED ON)

src/async_reader.cpp

@@ -31,7 +31,12 @@ void AsyncReader::scheduleRead(const ReadTask& entryTask)
     assert(entryTask.getHandler() != nullptr);
     assert(entryTask.getSize() != 0);
     pendingTask = entryTask;
+
+#if BOOST_VERSION >= 109000
     post(strand.wrap(
+#else
+    ioContextRef.post(strand.wrap(
+#endif
         [this, shared_self = shared_from_this()]()
         {
             doRead(pendingTask.getSize());

src/async_writer.cpp

@@ -17,7 +17,11 @@ AsyncWriter::AsyncWriter(boost::asio::io_context& ioContextRef, std::shared_ptr<
 
 void AsyncWriter::scheduleWrite(BatchedWriteTasks&& tasks, OptionalWriteDeadline&& deadlineTime)
 {
+#if BOOST_VERSION >= 109000
     post(strand.wrap(
+#else
+    ioContextRef.post(strand.wrap(
+#endif
         [this, tasks = std::move(tasks), deadlineTime = std::move(deadlineTime), shared_self = shared_from_this()]() mutable
         {
             queueBatchWrite(std::move(tasks), std::move(deadlineTime));