From 8e6ae5fe16fe1193771e8a14f79bf2f51e92b9f5 Mon Sep 17 00:00:00 2001
From: Michael Crosby <crosbymichael@gmail.com>
Date: Thu, 7 Nov 2019 11:26:07 -0500
Subject: [PATCH] Add ToResources func for spec to v2.Resources

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
---
 v2/cpu.go   | 14 ++++++++++++++
 v2/utils.go | 41 +++++++++++++++++++++++++++++++++++++++++
 2 files changed, 55 insertions(+)

diff --git a/v2/cpu.go b/v2/cpu.go
index 1203354c..cf939d50 100644
--- a/v2/cpu.go
+++ b/v2/cpu.go
@@ -19,6 +19,8 @@ package v2
 type CPU struct {
 	Weight *uint64
 	Max    *uint64
+	Cpus   string
+	Mems   string
 }
 
 func (r *CPU) Values() (o []Value) {
@@ -34,5 +36,17 @@ func (r *CPU) Values() (o []Value) {
 			value:    *r.Max,
 		})
 	}
+	if r.Cpus != "" {
+		o = append(o, Value{
+			filename: "cpuset.cpus",
+			value:    r.Cpus,
+		})
+	}
+	if r.Mems != "" {
+		o = append(o, Value{
+			filename: "cpuset.mems",
+			value:    r.Mems,
+		})
+	}
 	return o
 }
diff --git a/v2/utils.go b/v2/utils.go
index ebb5335b..076b5328 100644
--- a/v2/utils.go
+++ b/v2/utils.go
@@ -26,6 +26,7 @@ import (
 	"strings"
 	"time"
 
+	"github.com/opencontainers/runtime-spec/specs-go"
 	"github.com/pkg/errors"
 )
 
@@ -153,3 +154,43 @@ func parseCgroupFromReader(r io.Reader) (string, error) {
 	}
 	return "", fmt.Errorf("cgroup path not found")
 }
+
+// ToResources converts the oci LinuxResources struct into a
+// v2 Resources type for use with this package.
+//
+// converting cgroups configuration from v1 to v2
+// ref: https://github.com/containers/crun/blob/master/crun.1.md#cgroup-v2
+func ToResources(spec *specs.LinuxResources) *Resources {
+	var resources Resources
+	if cpu := spec.CPU; cpu != nil {
+		resources.CPU = &CPU{
+			Cpus: cpu.Cpus,
+			Mems: cpu.Mems,
+		}
+		if shares := cpu.Shares; shares != nil {
+			convertedWeight := (1 + ((*shares-2)*9999)/262142)
+			resources.CPU.Weight = &convertedWeight
+		}
+		if period := cpu.Period; period != nil {
+			resources.CPU.Max = period
+		}
+	}
+	if mem := spec.Memory; mem != nil {
+		resources.Memory = &Memory{}
+		if swap := mem.Swap; swap != nil {
+			resources.Memory.Swap = swap
+		}
+		if l := mem.Limit; l != nil {
+			resources.Memory.Max = l
+		}
+		if h := mem.Reservation; h != nil {
+			resources.Memory.High = h
+		}
+	}
+	if pids := spec.Pids; pids != nil {
+		resources.Pids = &Pids{
+			Max: pids.Limit,
+		}
+	}
+	return &resources
+}