X-Git-Url: https://tinc-vpn.org/git/browse?a=blobdiff_plain;ds=sidebyside;f=src%2Flinux%2Fevent.c;fp=src%2Flinux%2Fevent.c;h=ebcccfe70e4b8c814e4e4ca57a41d29b55ce0bd2;hb=021293e0d03de8d29b22104a8f9bef625b135640;hp=0000000000000000000000000000000000000000;hpb=d3849fcb278d1df005c507f7e18a8397574f7f47;p=tinc

diff --git a/src/linux/event.c b/src/linux/event.c
new file mode 100644
index 00000000..ebcccfe7
--- /dev/null
+++ b/src/linux/event.c
@@ -0,0 +1,169 @@
+/*
+    event.c -- epoll support for Linux
+    Copyright (C) 2012-2022 Guus Sliepen <guus@tinc-vpn.org>
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 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 General Public License for more details.
+
+    You should have received a copy of the GNU General Public License along
+    with this program; if not, write to the Free Software Foundation, Inc.,
+    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+*/
+
+#include "../system.h"
+
+#include <sys/epoll.h>
+
+#include "../event.h"
+#include "../utils.h"
+#include "../net.h"
+
+static bool running = false;
+static int epollset = 0;
+
+/* NOTE: 1024 limit is only used on ancient (pre 2.6.27) kernels.
+   Decent kernels will ignore this value making it unlimited.
+   epoll_create1 might be better, but these kernels would not be supported
+   in that case. */
+static inline void event_init(void) {
+	if(!epollset) {
+		epollset = epoll_create(1024);
+
+		if(epollset == -1) {
+			logger(DEBUG_ALWAYS, LOG_EMERG, "Could not initialize epoll: %s", strerror(errno));
+			abort();
+		}
+	}
+}
+
+static void event_deinit(void) {
+	if(epollset) {
+		close(epollset);
+		epollset = 0;
+	}
+}
+
+void io_add(io_t *io, io_cb_t cb, void *data, int fd, int flags) {
+	if(io->cb) {
+		return;
+	}
+
+	io->fd = fd;
+	io->cb = cb;
+	io->data = data;
+	io->node.data = io;
+
+	io_set(io, flags);
+}
+
+void io_set(io_t *io, int flags) {
+	event_init();
+
+	if(flags == io->flags) {
+		return;
+	}
+
+	io->flags = flags;
+
+	if(io->fd == -1) {
+		return;
+	}
+
+	epoll_ctl(epollset, EPOLL_CTL_DEL, io->fd, NULL);
+
+	struct epoll_event ev = {
+		.events = 0,
+		.data.ptr = io,
+	};
+
+	if(flags & IO_READ) {
+		ev.events |= EPOLLIN;
+	}
+
+	if(flags & IO_WRITE) {
+		ev.events |= EPOLLOUT;
+	} else if(ev.events == 0) {
+		io_tree.generation++;
+		return;
+	}
+
+	if(epoll_ctl(epollset, EPOLL_CTL_ADD, io->fd, &ev) < 0) {
+		logger(DEBUG_ALWAYS, LOG_EMERG, "epoll_ctl failed: %s", strerror(errno));
+		abort();
+	}
+}
+
+void io_del(io_t *io) {
+	if(io->cb) {
+		io_set(io, 0);
+		io->cb = NULL;
+	}
+}
+
+bool event_loop(void) {
+	event_init();
+	running = true;
+
+	while(running) {
+		struct timeval diff;
+		struct timeval *tv = timeout_execute(&diff);
+
+		struct epoll_event events[MAX_EVENTS_PER_LOOP];
+		long timeout = (tv->tv_sec * 1000) + (tv->tv_usec / 1000);
+
+		if(timeout > INT_MAX) {
+			timeout = INT_MAX;
+		}
+
+		int n = epoll_wait(epollset, events, MAX_EVENTS_PER_LOOP, (int)timeout);
+
+		if(n < 0) {
+			if(sockwouldblock(sockerrno)) {
+				continue;
+			} else {
+				return false;
+			}
+		}
+
+		if(!n) {
+			continue;
+		}
+
+		unsigned int curgen = io_tree.generation;
+
+		for(int i = 0; i < n; i++) {
+			io_t *io = events[i].data.ptr;
+
+			if(events[i].events & EPOLLOUT && io->flags & IO_WRITE) {
+				io->cb(io->data, IO_WRITE);
+			}
+
+			if(curgen != io_tree.generation) {
+				break;
+			}
+
+			if(events[i].events & EPOLLIN && io->flags & IO_READ) {
+				io->cb(io->data, IO_READ);
+			}
+
+			if(curgen != io_tree.generation) {
+				break;
+			}
+		}
+
+	}
+
+	event_deinit();
+	return true;
+}
+
+void event_exit(void) {
+	running = false;
+}