migrate to async IO model

new PIIODevice::interrupt() virtual method
new PIWaitEvent private class
PIEthernet and PISerial basically tested on Windows and Linux

libs/main/core/piwaitevent_p.cpp

@@ -0,0 +1,126 @@
+/*
+	PIP - Platform Independent Primitives
+	Private PIP wait object
+	Ivan Pelipenko peri4ko@yandex.ru
+
+	This program is free software: you can redistribute it and/or modify
+	it under the terms of the GNU Lesser General Public License as published by
+	the Free Software Foundation, either version 3 of the License, or
+	(at your option) any later version.
+
+	This program is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU Lesser General Public License for more details.
+
+	You should have received a copy of the GNU Lesser General Public License
+	along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "piwaitevent_p.h"
+#ifdef WINDOWS
+//#  ifdef _WIN32_WINNT
+//#    undef _WIN32_WINNT
+//#    define _WIN32_WINNT 0x0600
+//#  endif
+#  include <synchapi.h>
+#else
+#  include <fcntl.h>
+#  include <sys/ioctl.h>
+#endif
+#include "piincludes_p.h"
+#include "pistring.h"
+
+
+PIWaitEvent::~PIWaitEvent() {
+	destroy();
+}
+
+
+void PIWaitEvent::create() {
+	destroy();
+#ifdef WINDOWS
+	event = CreateEventA(NULL, TRUE, FALSE, NULL);
+	if (!event) {
+		piCout << "Error with CreateEventA:" << errorString();
+	}
+#else
+	for (int i = 0; i < 3; ++i) memset(&(fds[i]), 0, sizeof(fds[i]));
+	if (::pipe(pipe_fd) < 0) {
+		piCout << "Error with pipe:" << errorString();
+	} else {
+		fcntl(pipe_fd[ReadEnd], F_SETFL, O_NONBLOCK);
+	}
+#endif
+}
+
+
+void PIWaitEvent::destroy() {
+#ifdef WINDOWS
+	if (event) {
+		CloseHandle(event);
+		event = NULL;
+	}
+#else
+	for (int i = 0; i < 2; ++i) {
+		if (pipe_fd[i] != 0) {
+			::close(pipe_fd[i]);
+			pipe_fd[i] = 0;
+		}
+	}
+#endif
+}
+
+
+#ifdef WINDOWS
+bool PIWaitEvent::wait() {
+#else
+bool PIWaitEvent::wait(int fd, PIWaitEvent::SelectRole role) {
+#endif
+	if (!isCreate()) return false;
+#ifdef WINDOWS
+	DWORD ret = WaitForSingleObjectEx(event, INFINITE, TRUE);
+	ResetEvent(event);
+	if (ret == WAIT_IO_COMPLETION || ret == WAIT_FAILED) return false;
+#else
+	int nfds = piMaxi(pipe_fd[ReadEnd], fd) + 1;
+	int fd_index = 0;
+	switch (role) {
+	case CheckRead:
+		fd_index = 0;
+		break;
+	case CheckWrite:
+		fd_index = 1;
+		break;
+	}
+	for (int i = 0; i < 3; ++i) FD_ZERO(&(fds[i]));
+	FD_SET(pipe_fd[ReadEnd], &(fds[0]));
+	FD_SET(fd, &(fds[2]));
+	FD_SET(fd, &(fds[fd_index]));
+	::select(nfds, &(fds[0]), &(fds[1]), &(fds[2]), nullptr);
+	int buf = 0;
+	while (::read(pipe_fd[ReadEnd], &buf, sizeof(buf)) > 0);
+	if (FD_ISSET(fd, &(fds[2]))) return false;
+	return FD_ISSET(fd, &(fds[fd_index]));
+#endif
+	return true;
+}
+
+
+void PIWaitEvent::interrupt() {
+	if (!isCreate()) return;
+#ifdef WINDOWS
+	SetEvent(event);
+#else
+	::write(pipe_fd[WriteEnd], "", 1);
+#endif
+}
+
+
+bool PIWaitEvent::isCreate() const {
+#ifdef WINDOWS
+	return event;
+#else
+	return pipe_fd[ReadEnd] != 0;
+#endif
+}