podman: add --ulimit host

add a simple way to copy ulimit values from the host.

if --ulimit host is used then the current ulimits in place are copied
to the container.

Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>

1 files changed, 20 insertions, 0 deletions

diff --git a/pkg/spec/spec.go b/pkg/spec/spec.go
index 06d1ac12d..c9548f0d3 100644
--- a/pkg/spec/spec.go
+++ b/pkg/spec/spec.go
@@ -20,6 +20,12 @@ import (
 
 const cpuPeriod = 100000
 
+type systemUlimit struct {
+	name string
+	max  uint64
+	cur  uint64
+}
+
 func getAvailableGids() (int64, error) {
 	idMap, err := user.ParseIDMapFile("/proc/self/gid_map")
 	if err != nil {
@@ -553,6 +559,20 @@ func addRlimits(config *CreateConfig, g *generate.Generator) error {
 	)
 
 	for _, u := range config.Resources.Ulimit {
+		if u == "host" {
+			if len(config.Resources.Ulimit) != 1 {
+				return errors.New("ulimit can use host only once")
+			}
+			hostLimits, err := getHostRlimits()
+			if err != nil {
+				return err
+			}
+			for _, i := range hostLimits {
+				g.AddProcessRlimits(i.name, i.max, i.cur)
+			}
+			break
+		}
+
 		ul, err := units.ParseUlimit(u)
 		if err != nil {
 			return errors.Wrapf(err, "ulimit option %q requires name=SOFT:HARD, failed to be parsed", u)