1 files changed, 154 insertions, 0 deletions
diff --git a/libgo/runtime/netpoll_epoll.c b/libgo/runtime/netpoll_epoll.c
new file mode 100644
index 00000000000..04f9c756472
--- /dev/null
+++ b/libgo/runtime/netpoll_epoll.c
@@ -0,0 +1,154 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build linux
+
+#include <errno.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/epoll.h>
+
+#include "runtime.h"
+#include "defs.h"
+
+#ifndef EPOLLRDHUP
+#define EPOLLRDHUP 0x2000
+#endif
+
+#ifndef EPOLL_CLOEXEC
+#define EPOLL_CLOEXEC 02000000
+#endif
+
+typedef struct epoll_event EpollEvent;
+
+static int32
+runtime_epollcreate(int32 size)
+{
+	int r;
+
+	r = epoll_create(size);
+	if(r >= 0)
+		return r;
+	return - errno;
+}
+
+static int32
+runtime_epollcreate1(int32 flags)
+{
+	int r;
+
+	r = epoll_create1(flags);
+	if(r >= 0)
+		return r;
+	return - errno;
+}
+
+static int32
+runtime_epollctl(int32 epfd, int32 op, int32 fd, EpollEvent *ev)
+{
+	int r;
+
+	r = epoll_ctl(epfd, op, fd, ev);
+	if(r >= 0)
+		return r;
+	return - errno;
+}
+
+static int32
+runtime_epollwait(int32 epfd, EpollEvent *ev, int32 nev, int32 timeout)
+{
+	int r;
+
+	r = epoll_wait(epfd, ev, nev, timeout);
+	if(r >= 0)
+		return r;
+	return - errno;
+}
+
+static void
+runtime_closeonexec(int32 fd)
+{
+	fcntl(fd, F_SETFD, FD_CLOEXEC);
+}
+
+static int32 epfd = -1;  // epoll descriptor
+
+void
+runtime_netpollinit(void)
+{
+	epfd = runtime_epollcreate1(EPOLL_CLOEXEC);
+	if(epfd >= 0)
+		return;
+	epfd = runtime_epollcreate(1024);
+	if(epfd >= 0) {
+		runtime_closeonexec(epfd);
+		return;
+	}
+	runtime_printf("netpollinit: failed to create descriptor (%d)\n", -epfd);
+	runtime_throw("netpollinit: failed to create descriptor");
+}
+
+int32
+runtime_netpollopen(int32 fd, PollDesc *pd)
+{
+	EpollEvent ev;
+	int32 res;
+
+	ev.events = EPOLLIN|EPOLLOUT|EPOLLRDHUP|EPOLLET;
+	ev.data.ptr = (void*)pd;
+	res = runtime_epollctl(epfd, EPOLL_CTL_ADD, fd, &ev);
+	return -res;
+}
+
+int32
+runtime_netpollclose(int32 fd)
+{
+	EpollEvent ev;
+	int32 res;
+
+	res = runtime_epollctl(epfd, EPOLL_CTL_DEL, fd, &ev);
+	return -res;
+}
+
+// polls for ready network connections
+// returns list of goroutines that become runnable
+G*
+runtime_netpoll(bool block)
+{
+	static int32 lasterr;
+	EpollEvent events[128], *ev;
+	int32 n, i, waitms, mode;
+	G *gp;
+
+	if(epfd == -1)
+		return nil;
+	waitms = -1;
+	if(!block)
+		waitms = 0;
+retry:
+	n = runtime_epollwait(epfd, events, nelem(events), waitms);
+	if(n < 0) {
+		if(n != -EINTR && n != lasterr) {
+			lasterr = n;
+			runtime_printf("runtime: epollwait on fd %d failed with %d\n", epfd, -n);
+		}
+		goto retry;
+	}
+	gp = nil;
+	for(i = 0; i < n; i++) {
+		ev = &events[i];
+		if(ev->events == 0)
+			continue;
+		mode = 0;
+		if(ev->events & (EPOLLIN|EPOLLRDHUP|EPOLLHUP|EPOLLERR))
+			mode += 'r';
+		if(ev->events & (EPOLLOUT|EPOLLHUP|EPOLLERR))
+			mode += 'w';
+		if(mode)
+			runtime_netpollready(&gp, (void*)ev->data.ptr, mode);
+	}
+	if(block && gp == nil)
+		goto retry;
+	return gp;
+}