Fix freebsd build

This brings freebsd in line with Darwin, ie it builds, but some parts may not yet
be fully functional. There is now a WIP `runc` port for FreeBSD at
https://github.com/clovertrail/runc/tree/1501-SupportOnFreeBSD so should be able
to test further.

Signed-off-by: Justin Cormack <justin@specialbusservice.com>

cmd/containerd-shim/shim_freebsd.go

@@ -1,4 +1,4 @@
-// +build !linux,!windows,!darwin
+// +build freebsd
 
 /*
    Copyright The containerd Authors.
@@ -39,5 +39,8 @@ func setupSignals() (chan os.Signal, error) {
 }
 
 func newServer() (*ttrpc.Server, error) {
-	return ttrpc.NewServer(ttrpc.WithServerHandshaker(ttrpc.UnixSocketRequireSameUser()))
+	// for freebsd, we omit the socket credentials because these syscalls are
+	// slightly different. since we don't have freebsd support yet, this can be
+	// implemented later and the build can continue without issue.
+	return ttrpc.NewServer()
 }

cmd/containerd-stress/rlimit_freebsd.go

@@ -0,0 +1,40 @@
+// +build freebsd
+
+/*
+   Copyright The containerd Authors.
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+*/
+
+package main
+
+import (
+	"syscall"
+)
+
+func setRlimit() error {
+	rlimit := int64(100000)
+	if rlimit > 0 {
+		var limit syscall.Rlimit
+		if err := syscall.Getrlimit(syscall.RLIMIT_NOFILE, &limit); err != nil {
+			return err
+		}
+		if limit.Cur < rlimit {
+			limit.Cur = rlimit
+			if err := syscall.Setrlimit(syscall.RLIMIT_NOFILE, &limit); err != nil {
+				return err
+			}
+		}
+	}
+	return nil
+}

cmd/containerd-stress/rlimit_unix.go

@@ -1,4 +1,4 @@
-// +build !windows
+// +build !windows,!freebsd
 
 /*
    Copyright The containerd Authors.

runtime/v2/shim/shim_freebsd.go

@@ -0,0 +1,29 @@
+// +build freebsd
+
+/*
+   Copyright The containerd Authors.
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+*/
+
+package shim
+
+import "github.com/containerd/ttrpc"
+
+func newServer() (*ttrpc.Server, error) {
+	return ttrpc.NewServer()
+}
+
+func subreaper() error {
+	return nil
+}