bus: add API call to create bus connection to the system bus of local containers

Also, add support for this to machinectl, so that we can enumerate the
machines that run inside a container. We must go deeper!

1 files changed, 43 insertions, 47 deletions

diff --git a/src/machine/machinectl.c b/src/machine/machinectl.c
index 241e360d49..83c5da3806 100644
--- a/src/machine/machinectl.c
+++ b/src/machine/machinectl.c
@@ -47,12 +47,12 @@ static bool arg_no_pager = false;
 static const char *arg_kill_who = NULL;
 static int arg_signal = SIGTERM;
 static enum transport {
-        TRANSPORT_NORMAL,
-        TRANSPORT_SSH,
-} arg_transport = TRANSPORT_NORMAL;
+        TRANSPORT_LOCAL,
+        TRANSPORT_REMOTE,
+        TRANSPORT_CONTAINER
+} arg_transport = TRANSPORT_LOCAL;
 static bool arg_ask_password = true;
 static char *arg_host = NULL;
-static char *arg_user = NULL;
 
 static void pager_open_if_enabled(void) {
 
@@ -94,9 +94,6 @@ static int list_machines(sd_bus *bus, char **args, unsigned n) {
                 goto fail;
 
         while ((r = sd_bus_message_read(reply, "(ssso)", &name, &class, &service, &object)) > 0) {
-                if (r < 0)
-                        goto fail;
-
                 printf("%-32s %-9s %-16s\n", name, class, service);
 
                 k++;
@@ -115,7 +112,7 @@ static int list_machines(sd_bus *bus, char **args, unsigned n) {
 
 fail:
         log_error("Failed to parse reply: %s", strerror(-r));
-        return -EIO;
+        return r;
 }
 
 static int show_scope_cgroup(sd_bus *bus, const char *unit, pid_t leader) {
@@ -129,30 +126,28 @@ static int show_scope_cgroup(sd_bus *bus, const char *unit, pid_t leader) {
         assert(bus);
         assert(unit);
 
-        if (arg_transport == TRANSPORT_SSH)
+        if (arg_transport == TRANSPORT_REMOTE)
                 return 0;
 
         path = unit_dbus_path_from_name(unit);
         if (!path)
                 return log_oom();
 
-        r = sd_bus_call_method(
+        r = sd_bus_get_property(
                         bus,
                         "org.freedesktop.systemd1",
                         path,
-                        "org.freedesktop.DBus.Properties",
-                        "Get",
+                        "org.freedesktop.systemd1.Scope",
+                        "ControlGroup",
                         &error,
                         &reply,
-                        "ss",
-                        "org.freedesktop.systemd1.Scope",
-                        "ControlGroup");
+                        "s");
         if (r < 0) {
                 log_error("Failed to query ControlGroup: %s", bus_error_message(&error, -r));
                 return r;
         }
 
-        r = sd_bus_message_read(reply, "v", "s", &cgroup);
+        r = sd_bus_message_read(reply, "s", &cgroup);
         if (r < 0) {
                 log_error("Failed to parse reply: %s", strerror(-r));
                 return r;
@@ -371,9 +366,6 @@ static int show_one(const char *verb, sd_bus *bus, const char *path, bool show_p
                 const char *name;
                 const char *contents;
 
-                if (r < 0)
-                        goto fail;
-
                 r = sd_bus_message_read_basic(reply, SD_BUS_TYPE_STRING, &name);
                 if (r < 0)
                         goto fail;
@@ -415,7 +407,7 @@ static int show_one(const char *verb, sd_bus *bus, const char *path, bool show_p
 
 fail:
         log_error("Failed to parse reply: %s", strerror(-r));
-        return -EIO;
+        return r;
 }
 
 static int show(sd_bus *bus, char **args, unsigned n) {
@@ -460,7 +452,7 @@ static int show(sd_bus *bus, char **args, unsigned n) {
                 r = sd_bus_message_read(reply, "o", &path);
                 if (r < 0) {
                         log_error("Failed to parse reply: %s", strerror(-r));
-                        return -EIO;
+                        return r;
                 }
 
                 r = show_one(args[0], bus, path, show_properties, &new_line);
@@ -534,14 +526,15 @@ static int help(void) {
                "Send control commands to or query the virtual machine and container registration manager.\n\n"
                "  -h --help              Show this help\n"
                "     --version           Show package version\n"
+               "     --no-pager          Do not pipe output into a pager\n"
+               "     --no-ask-password   Don't prompt for password\n"
+               "  -H --host=[USER@]HOST  Show information for remote host\n"
+               "  -M --machine=CONTAINER Show information for local container\n"
                "  -p --property=NAME     Show only properties by this name\n"
                "  -a --all               Show all properties, including empty ones\n"
-               "     --kill-who=WHO      Who to send signal to\n"
                "  -l --full              Do not ellipsize output\n"
-               "  -s --signal=SIGNAL     Which signal to send\n"
-               "     --no-ask-password   Don't prompt for password\n"
-               "  -H --host=[USER@]HOST  Show information for remote host\n"
-               "     --no-pager          Do not pipe output into a pager\n\n"
+               "     --kill-who=WHO      Who to send signal to\n"
+               "  -s --signal=SIGNAL     Which signal to send\n\n"
                "Commands:\n"
                "  list                   List running VMs and containers\n"
                "  status [NAME...]       Show VM/container status\n"
@@ -572,16 +565,17 @@ static int parse_argv(int argc, char *argv[]) {
                 { "kill-who",        required_argument, NULL, ARG_KILL_WHO        },
                 { "signal",          required_argument, NULL, 's'                 },
                 { "host",            required_argument, NULL, 'H'                 },
+                { "machine",         required_argument, NULL, 'M'                 },
                 { "no-ask-password", no_argument,       NULL, ARG_NO_ASK_PASSWORD },
                 { NULL,              0,                 NULL, 0                   }
         };
 
-        int c;
+        int c, r;
 
         assert(argc >= 0);
         assert(argv);
 
-        while ((c = getopt_long(argc, argv, "hp:als:H:P", options, NULL)) >= 0) {
+        while ((c = getopt_long(argc, argv, "hp:als:H:M:", options, NULL)) >= 0) {
 
                 switch (c) {
 
@@ -594,22 +588,16 @@ static int parse_argv(int argc, char *argv[]) {
                         puts(SYSTEMD_FEATURES);
                         return 0;
 
-                case 'p': {
-                        char **l;
-
-                        l = strv_append(arg_property, optarg);
-                        if (!l)
-                                return -ENOMEM;
-
-                        strv_free(arg_property);
-                        arg_property = l;
+                case 'p':
+                        r = strv_extend(&arg_property, optarg);
+                        if (r < 0)
+                                return log_oom();
 
                         /* If the user asked for a particular
                          * property, show it to him, even if it is
                          * empty. */
                         arg_all = true;
                         break;
-                }
 
                 case 'a':
                         arg_all = true;
@@ -640,8 +628,13 @@ static int parse_argv(int argc, char *argv[]) {
                         break;
 
                 case 'H':
-                        arg_transport = TRANSPORT_SSH;
-                        parse_user_at_host(optarg, &arg_user, &arg_host);
+                        arg_transport = TRANSPORT_REMOTE;
+                        arg_host = optarg;
+                        break;
+
+                case 'M':
+                        arg_transport = TRANSPORT_CONTAINER;
+                        arg_host = optarg;
                         break;
 
                 case '?':
@@ -741,7 +734,7 @@ static int machinectl_main(sd_bus *bus, int argc, char *argv[], const int r) {
 }
 
 int main(int argc, char*argv[]) {
-        int r, retval = EXIT_FAILURE;
+        int r, ret = EXIT_FAILURE;
         _cleanup_bus_unref_ sd_bus *bus = NULL;
 
         setlocale(LC_ALL, "");
@@ -752,28 +745,31 @@ int main(int argc, char*argv[]) {
         if (r < 0)
                 goto finish;
         else if (r == 0) {
-                retval = EXIT_SUCCESS;
+                ret = EXIT_SUCCESS;
                 goto finish;
         }
 
-        if (arg_transport == TRANSPORT_NORMAL)
+        if (arg_transport == TRANSPORT_LOCAL)
                 r = sd_bus_open_system(&bus);
-        else if (arg_transport == TRANSPORT_SSH)
+        else if (arg_transport == TRANSPORT_REMOTE)
                 r = sd_bus_open_system_remote(arg_host, &bus);
+        else if (arg_transport == TRANSPORT_CONTAINER)
+                r = sd_bus_open_system_container(arg_host, &bus);
         else
                 assert_not_reached("Uh, invalid transport...");
         if (r < 0) {
-                retval = EXIT_FAILURE;
+                log_error("Failed to connect to machined: %s", strerror(-r));
+                ret = EXIT_FAILURE;
                 goto finish;
         }
 
         r = machinectl_main(bus, argc, argv, r);
-        retval = r < 0 ? EXIT_FAILURE : r;
+        ret = r < 0 ? EXIT_FAILURE : r;
 
 finish:
         strv_free(arg_property);
 
         pager_close();
 
-        return retval;
+        return ret;
 }