containerd build clean on Solaris (#203)

* containerd build clean on Solaris

Signed-off-by: Amit Krishnan <krish.amit@gmail.com>

* Vendor golang.org/x/sys

Signed-off-by: Amit Krishnan <krish.amit@gmail.com>

runtime/container_linux.go

@@ -0,0 +1,134 @@
+package runtime
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+	"syscall"
+
+	"github.com/docker/containerd/specs"
+	"github.com/opencontainers/runc/libcontainer"
+	ocs "github.com/opencontainers/runtime-spec/specs-go"
+)
+
+func (c *container) getLibctContainer() (libcontainer.Container, error) {
+	runtimeRoot := "/run/runc"
+
+	// Check that the root wasn't changed
+	for _, opt := range c.runtimeArgs {
+		if strings.HasPrefix(opt, "--root=") {
+			runtimeRoot = strings.TrimPrefix(opt, "--root=")
+			break
+		}
+	}
+
+	f, err := libcontainer.New(runtimeRoot, libcontainer.Cgroupfs)
+	if err != nil {
+		return nil, err
+	}
+	return f.Load(c.id)
+}
+
+func (c *container) OOM() (OOM, error) {
+	container, err := c.getLibctContainer()
+	if err != nil {
+		if lerr, ok := err.(libcontainer.Error); ok {
+			// with oom registration sometimes the container can run, exit, and be destroyed
+			// faster than we can get the state back so we can just ignore this
+			if lerr.Code() == libcontainer.ContainerNotExists {
+				return nil, ErrContainerExited
+			}
+		}
+		return nil, err
+	}
+	state, err := container.State()
+	if err != nil {
+		return nil, err
+	}
+	memoryPath := state.CgroupPaths["memory"]
+	return c.getMemeoryEventFD(memoryPath)
+}
+
+func u64Ptr(i uint64) *uint64 { return &i }
+
+func (c *container) UpdateResources(r *Resource) error {
+	sr := ocs.Resources{
+		Memory: &ocs.Memory{
+			Limit:       u64Ptr(uint64(r.Memory)),
+			Reservation: u64Ptr(uint64(r.MemoryReservation)),
+			Swap:        u64Ptr(uint64(r.MemorySwap)),
+			Kernel:      u64Ptr(uint64(r.KernelMemory)),
+		},
+		CPU: &ocs.CPU{
+			Shares: u64Ptr(uint64(r.CPUShares)),
+			Quota:  u64Ptr(uint64(r.CPUQuota)),
+			Period: u64Ptr(uint64(r.CPUPeriod)),
+			Cpus:   &r.CpusetCpus,
+			Mems:   &r.CpusetMems,
+		},
+		BlockIO: &ocs.BlockIO{
+			Weight: &r.BlkioWeight,
+		},
+	}
+
+	srStr := bytes.NewBuffer(nil)
+	if err := json.NewEncoder(srStr).Encode(&sr); err != nil {
+		return err
+	}
+
+	args := c.runtimeArgs
+	args = append(args, "update", "-r", "-", c.id)
+	cmd := exec.Command(c.runtime, args...)
+	cmd.Stdin = srStr
+	b, err := cmd.CombinedOutput()
+	if err != nil {
+		return fmt.Errorf(string(b))
+	}
+	return nil
+}
+
+func getRootIDs(s *specs.Spec) (int, int, error) {
+	if s == nil {
+		return 0, 0, nil
+	}
+	var hasUserns bool
+	for _, ns := range s.Linux.Namespaces {
+		if ns.Type == ocs.UserNamespace {
+			hasUserns = true
+			break
+		}
+	}
+	if !hasUserns {
+		return 0, 0, nil
+	}
+	uid := hostIDFromMap(0, s.Linux.UIDMappings)
+	gid := hostIDFromMap(0, s.Linux.GIDMappings)
+	return uid, gid, nil
+}
+
+func (c *container) getMemeoryEventFD(root string) (*oom, error) {
+	f, err := os.Open(filepath.Join(root, "memory.oom_control"))
+	if err != nil {
+		return nil, err
+	}
+	fd, _, serr := syscall.RawSyscall(syscall.SYS_EVENTFD2, 0, syscall.FD_CLOEXEC, 0)
+	if serr != 0 {
+		f.Close()
+		return nil, serr
+	}
+	if err := c.writeEventFD(root, int(f.Fd()), int(fd)); err != nil {
+		syscall.Close(int(fd))
+		f.Close()
+		return nil, err
+	}
+	return &oom{
+		root:    root,
+		id:      c.id,
+		eventfd: int(fd),
+		control: f,
+	}, nil
+}