lib/io: refactor I/O module

1 files changed, 58 insertions, 0 deletions

diff --git a/ttwhy/io/signal_handling.cppm b/ttwhy/io/signal_handling.cppm
new file mode 100644
index 0000000..1f3fecc
--- /dev/null
+++ b/ttwhy/io/signal_handling.cppm
@@ -0,0 +1,58 @@
+module;
+
+#include <asio.hpp>
+
+#include <csignal>
+#include <format>
+#include <system_error>
+
+export module ttwhy.io:signal_handling;
+
+namespace ttwhy::io
+{
+
+  export template<typename Stream, typename TerminalAttributes>
+  auto handle_signals(Stream & stream, TerminalAttributes & attributes) -> asio::awaitable<std::error_code>
+  {
+    auto executor = co_await asio::this_coro::executor;
+    auto signals = asio::signal_set{executor, SIGINT, SIGTERM};
+    signals.add(SIGTSTP);
+    signals.add(SIGCONT);
+
+    while (true)
+    {
+      auto [error, signal] = co_await signals.async_wait(asio::as_tuple(asio::use_awaitable));
+      if (error)
+      {
+        co_return error;
+      }
+
+      switch (signal)
+      {
+        case SIGINT:
+        case SIGTERM:
+        {
+          auto message = std::format("Received signal {}, exiting ...\n", signal);
+          co_await asio::async_write(stream, asio::buffer(message), asio::use_awaitable);
+          co_return asio::error_code{};
+        }
+        case SIGTSTP:
+        {
+          attributes.canonical_mode(true).echo(true);
+          ::raise(SIGSTOP);
+          break;
+        }
+        case SIGCONT:
+        {
+          attributes.canonical_mode(false).echo(false);
+          break;
+        }
+      }
+
+      if (!error)
+      {
+      }
+    }
+  }
+
+}  // namespace ttwhy::io