Added linux scheduler

include/cppcoro/detail/linux.hpp

@@ -0,0 +1,113 @@
+///////////////////////////////////////////////////////////////////////////////
+// Copyright (c) Microsoft
+// Licenced under MIT license. See LICENSE.txt for details.
+///////////////////////////////////////////////////////////////////////////////
+#ifndef CPPCORO_DETAIL_LINUX_HPP_INCLUDED
+#define CPPCORO_DETAIL_LINUX_HPP_INCLUDED
+
+#include <fcntl.h>
+#include <linux/limits.h>
+#include <sys/epoll.h>
+#include <sys/eventfd.h>
+#include <sys/resource.h>
+#include <sys/stat.h>
+#include <sys/timerfd.h>
+#include <unistd.h>
+#include <utility>
+
+namespace cppcoro
+{
+	namespace detail
+	{
+		namespace linux
+		{
+			using fd_t = int;
+
+			enum message_type
+			{
+				CALLBACK_TYPE,
+				RESUME_TYPE
+			};
+
+			class safe_fd
+			{
+			public:
+				safe_fd()
+					: m_fd(-1)
+				{
+				}
+
+				explicit safe_fd(fd_t fd)
+					: m_fd(fd)
+				{
+				}
+
+				safe_fd(const safe_fd& other) = delete;
+
+				safe_fd(safe_fd&& other) noexcept
+					: m_fd(other.m_fd)
+				{
+					other.m_fd = -1;
+				}
+
+				~safe_fd() { close(); }
+
+				safe_fd& operator=(safe_fd fd) noexcept
+				{
+					swap(fd);
+					return *this;
+				}
+
+				constexpr fd_t fd() const { return m_fd; }
+
+				/// Calls close() and sets the fd to -1.
+				void close() noexcept;
+
+				void swap(safe_fd& other) noexcept { std::swap(m_fd, other.m_fd); }
+
+				bool operator==(const safe_fd& other) const { return m_fd == other.m_fd; }
+
+				bool operator!=(const safe_fd& other) const { return m_fd != other.m_fd; }
+
+				bool operator==(fd_t fd) const { return m_fd == fd; }
+
+				bool operator!=(fd_t fd) const { return m_fd != fd; }
+
+			private:
+				fd_t m_fd;
+			};
+
+			struct message
+			{
+				enum message_type m_type;
+				void* m_ptr;
+			};
+
+			struct io_state : linux::message
+			{
+				using callback_type = void(io_state* state);
+				callback_type* m_callback;
+			};
+
+			class message_queue
+			{
+			private:
+				int m_pipefd[2];
+				safe_fd m_epollfd;
+				struct epoll_event m_ev;
+
+			public:
+				message_queue();
+				~message_queue();
+				bool enqueue_message(void* message, message_type type);
+				bool dequeue_message(void*& message, message_type& type, bool wait);
+			};
+
+			safe_fd create_event_fd();
+			safe_fd create_timer_fd();
+			safe_fd create_epoll_fd();
+		}  // namespace linux
+	}      // namespace detail
+}  // namespace cppcoro
+
+#endif

include/cppcoro/io_service.hpp

@@ -11,6 +11,8 @@
 
 #if CPPCORO_OS_WINNT
 # include <cppcoro/detail/win32.hpp>
+#elif CPPCORO_OS_LINUX
+# include <cppcoro/detail/linux.hpp>
 #endif
 
 #include <optional>
@@ -172,6 +174,9 @@ namespace cppcoro
 
 		std::atomic<bool> m_winsockInitialised;
 		std::mutex m_winsockInitialisationMutex;
+
+#elif CPPCORO_OS_LINUX
+ 		detail::linux::message_queue m_mq;
 #endif
 
 		// Head of a linked-list of schedule operations that are

include/cppcoro/resume_on.hpp

@@ -117,11 +117,12 @@ namespace cppcoro
 	template<typename SCHEDULER, typename T>
 	async_generator<T> resume_on(SCHEDULER& scheduler, async_generator<T> source)
 	{
-		for (auto iter = co_await source.begin(); iter != source.end(); co_await ++iter)
+		for (detail::async_generator_iterator<T> iter = co_await source.begin(); iter != source.end();)
 		{
 			auto& value = *iter;
 			co_await scheduler.schedule();
 			co_yield value;
+			co_await ++iter; // moved due to error: insufficient contextual information to determine type on old compilers
 		}
 	}
 }

lib/CMakeLists.txt

@@ -152,6 +152,17 @@ if(WIN32)
       # TODO remove this when experimental/non-experimental include are fixed
       list(APPEND compile_definition _SILENCE_EXPERIMENTAL_FILESYSTEM_DEPRECATION_WARNING=1)
     endif()
+elseif(CMAKE_SYSTEM_NAME MATCHES "Linux")
+    set(linuxDetailIncludes
+        linux.hpp
+    )
+    list(TRANSFORM linuxDetailIncludes PREPEND "${PROJECT_SOURCE_DIR}/include/cppcoro/detail/")
+    list(APPEND detailIncludes ${linuxDetailIncludes})
+
+    list(APPEND sources
+        linux.cpp
+        io_service.cpp
+    )
 endif()
 
 add_library(cppcoro