From b93e7b907abab2e92786e1859c0cc313eea71678 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?L=C3=A9o=20Gillot-Lamure?= <leo.gillot@navaati.net>
Date: Wed, 11 Apr 2012 12:27:19 +0100
Subject: [PATCH] One can specify in which cgroup hierarchies a systemd-nspawn
 container will appear

---
 man/systemd-nspawn.xml |   10 ++++++++++
 src/nspawn.c           |   27 ++++++++++++++++++++++++++-
 2 files changed, 36 insertions(+), 1 deletion(-)

diff --git a/man/systemd-nspawn.xml b/man/systemd-nspawn.xml
index dbd2ff5..47aa4a7 100644
--- a/man/systemd-nspawn.xml
+++ b/man/systemd-nspawn.xml
@@ -155,6 +155,16 @@
                         </varlistentry>
 
                         <varlistentry>
+                                <term><option>--controllers=</option></term>
+                                <term><option>-C</option></term>
+
+                                <listitem><para>Makes the container appear in
+                                other hierarchies that the name=systemd:/ one.
+                                Takes a comma-separated list of controllers.
+                                </para></listitem>
+                        </varlistentry>
+
+                        <varlistentry>
                                 <term><option>--private-network</option></term>
 
                                 <listitem><para>Turn off networking in
diff --git a/src/nspawn.c b/src/nspawn.c
index 6f5a9d9..558695c 100644
--- a/src/nspawn.c
+++ b/src/nspawn.c
@@ -50,6 +50,7 @@
 
 static char *arg_directory = NULL;
 static char *arg_user = NULL;
+static char *arg_controllers = NULL;
 static bool arg_private_network = false;
 
 static int help(void) {
@@ -59,6 +60,7 @@ static int help(void) {
                "  -h --help            Show this help\n"
                "  -D --directory=NAME  Root directory for the container\n"
                "  -u --user=USER       Run the command under specified user or uid\n"
+               "  -C --controllers=CON Put the container in specified comma-separated cgroup hierarchies\n"
                "     --private-network Disable network in container\n",
                program_invocation_short_name);
 
@@ -75,6 +77,7 @@ static int parse_argv(int argc, char *argv[]) {
                 { "help",            no_argument,       NULL, 'h'                 },
                 { "directory",       required_argument, NULL, 'D'                 },
                 { "user",            required_argument, NULL, 'u'                 },
+                { "controllers",     required_argument, NULL, 'C'                 },
                 { "private-network", no_argument,       NULL, ARG_PRIVATE_NETWORK },
                 { NULL,              0,                 NULL, 0                   }
         };
@@ -84,7 +87,7 @@ static int parse_argv(int argc, char *argv[]) {
         assert(argc >= 0);
         assert(argv);
 
-        while ((c = getopt_long(argc, argv, "+hD:u:", options, NULL)) >= 0) {
+        while ((c = getopt_long(argc, argv, "+hD:u:C:", options, NULL)) >= 0) {
 
                 switch (c) {
 
@@ -110,6 +113,15 @@ static int parse_argv(int argc, char *argv[]) {
 
                         break;
 
+                case 'C':
+                        free(arg_controllers);
+                        if (!(arg_controllers = strdup(optarg))) {
+                                log_error("Failed to duplicate controller list.");
+                                return -ENOMEM;
+                        }
+
+                        break;
+
                 case ARG_PRIVATE_NETWORK:
                         arg_private_network = true;
                         break;
@@ -674,6 +686,19 @@ int main(int argc, char *argv[]) {
                 goto finish;
         }
 
+        if (arg_controllers) {
+                char *controller;
+                controller = strtok(arg_controllers,",");
+                do {
+                        if ((k = cg_create_and_attach(controller, newcg, 0)) < 0)  {
+                                log_error("Failed to create cgroup: %s", strerror(-k));
+                                goto finish;
+                        }
+                } while((controller = strtok(NULL,",")));
+                free(controller);
+                free(arg_controllers);
+        }
+
         if ((master = posix_openpt(O_RDWR|O_NOCTTY|O_CLOEXEC|O_NDELAY)) < 0) {
                 log_error("Failed to acquire pseudo tty: %m");
                 goto finish;
-- 
1.7.10