Revert "nspawn: Allow specifying custom init program"

I don't actually need this anymore since we're going with a
unit based approach for the containers stuff internally so
let's just revert it.

Fixes #34085

This reverts commit ce2291730d5f91190e97e7c515ac772ae4970062.

3 files changed, 10 insertions, 38 deletions

diff --git a/src/nspawn/nspawn-gperf.gperf b/src/nspawn/nspawn-gperf.gperf
index b112f5d261..123ef0c6c8 100644
--- a/src/nspawn/nspawn-gperf.gperf
+++ b/src/nspawn/nspawn-gperf.gperf
@@ -20,7 +20,6 @@ struct ConfigPerfItem;
 %includes
 %%
 Exec.Boot,                    config_parse_boot,           0,                        0
-Exec.Init,                    config_parse_path,           0,                        offsetof(Settings, init)
 Exec.Ephemeral,               config_parse_tristate,       0,                        offsetof(Settings, ephemeral)
 Exec.ProcessTwo,              config_parse_pid2,           0,                        0
 Exec.Parameters,              config_parse_strv,           0,                        offsetof(Settings, parameters)
diff --git a/src/nspawn/nspawn-settings.h b/src/nspawn/nspawn-settings.h
index e48db0fdc3..135b3dbb0a 100644
--- a/src/nspawn/nspawn-settings.h
+++ b/src/nspawn/nspawn-settings.h
@@ -125,10 +125,9 @@ typedef enum SettingsMask {
         SETTING_CREDENTIALS       = UINT64_C(1) << 30,
         SETTING_BIND_USER         = UINT64_C(1) << 31,
         SETTING_SUPPRESS_SYNC     = UINT64_C(1) << 32,
-        SETTING_INIT              = UINT64_C(1) << 33,
-        SETTING_RLIMIT_FIRST      = UINT64_C(1) << 34, /* we define one bit per resource limit here */
-        SETTING_RLIMIT_LAST       = UINT64_C(1) << (34 + _RLIMIT_MAX - 1),
-        _SETTINGS_MASK_ALL        = (UINT64_C(1) << (34 + _RLIMIT_MAX)) - 1,
+        SETTING_RLIMIT_FIRST      = UINT64_C(1) << 33, /* we define one bit per resource limit here */
+        SETTING_RLIMIT_LAST       = UINT64_C(1) << (33 + _RLIMIT_MAX - 1),
+        _SETTINGS_MASK_ALL        = (UINT64_C(1) << (33 + _RLIMIT_MAX)) -1,
         _SETTING_FORCE_ENUM_WIDTH = UINT64_MAX
 } SettingsMask;
 
@@ -160,7 +159,6 @@ typedef struct OciHook {
 typedef struct Settings {
         /* [Exec] */
         StartMode start_mode;
-        char *init;
         int ephemeral;
         char **parameters;
         char **environment;
diff --git a/src/nspawn/nspawn.c b/src/nspawn/nspawn.c
index 8c68a2058c..9cd52e06c0 100644
--- a/src/nspawn/nspawn.c
+++ b/src/nspawn/nspawn.c
@@ -139,7 +139,6 @@ static char *arg_slice = NULL;
 static bool arg_private_network = false;
 static bool arg_read_only = false;
 static StartMode arg_start_mode = START_PID1;
-static char *arg_init = NULL;
 static bool arg_ephemeral = false;
 static LinkJournal arg_link_journal = LINK_AUTO;
 static bool arg_link_journal_try = false;
@@ -245,7 +244,6 @@ STATIC_DESTRUCTOR_REGISTER(arg_supplementary_gids, freep);
 STATIC_DESTRUCTOR_REGISTER(arg_machine, freep);
 STATIC_DESTRUCTOR_REGISTER(arg_hostname, freep);
 STATIC_DESTRUCTOR_REGISTER(arg_slice, freep);
-STATIC_DESTRUCTOR_REGISTER(arg_init, freep);
 STATIC_DESTRUCTOR_REGISTER(arg_setenv, strv_freep);
 STATIC_DESTRUCTOR_REGISTER(arg_network_interfaces, strv_freep);
 STATIC_DESTRUCTOR_REGISTER(arg_network_macvlan, strv_freep);
@@ -349,7 +347,6 @@ static int help(void) {
                "\n%3$sExecution:%4$s\n"
                "  -a --as-pid2              Maintain a stub init as PID1, invoke binary as PID2\n"
                "  -b --boot                 Boot up full system (i.e. invoke init)\n"
-               "     --init=PATH            Path to init to invoke\n"
                "     --chdir=PATH           Set working directory in the container\n"
                "  -E --setenv=NAME[=VALUE]  Pass an environment variable to PID 1\n"
                "  -u --user=USER            Run the command under specified user or UID\n"
@@ -700,7 +697,6 @@ static int parse_argv(int argc, char *argv[]) {
         enum {
                 ARG_VERSION = 0x100,
                 ARG_PRIVATE_NETWORK,
-                ARG_INIT,
                 ARG_UUID,
                 ARG_READ_ONLY,
                 ARG_CAPABILITY,
@@ -768,7 +764,6 @@ static int parse_argv(int argc, char *argv[]) {
                 { "private-network",        no_argument,       NULL, ARG_PRIVATE_NETWORK        },
                 { "as-pid2",                no_argument,       NULL, 'a'                        },
                 { "boot",                   no_argument,       NULL, 'b'                        },
-                { "init",                   required_argument, NULL, ARG_INIT                   },
                 { "uuid",                   required_argument, NULL, ARG_UUID                   },
                 { "read-only",              no_argument,       NULL, ARG_READ_ONLY              },
                 { "capability",             required_argument, NULL, ARG_CAPABILITY             },
@@ -989,14 +984,6 @@ static int parse_argv(int argc, char *argv[]) {
                         arg_settings_mask |= SETTING_START_MODE;
                         break;
 
-                case ARG_INIT:
-                        r = parse_path_argument(optarg, /* suppress_root= */ false, &arg_init);
-                        if (r < 0)
-                                return r;
-
-                        arg_settings_mask |= SETTING_INIT;
-                        break;
-
                 case 'a':
                         if (arg_start_mode == START_BOOT)
                                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
@@ -1791,9 +1778,6 @@ static int verify_arguments(void) {
         if (arg_userns_mode == USER_NAMESPACE_NO && !strv_isempty(arg_bind_user))
                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "--bind-user= requires --private-users");
 
-        if (arg_start_mode != START_BOOT && arg_init)
-                return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Cannot use --init= without --boot");
-
         /* Drop duplicate --bind-user= entries */
         strv_uniq(arg_bind_user);
 
@@ -3606,21 +3590,15 @@ static int inner_child(
                 memcpy_safe(a + 1, arg_parameters, m * sizeof(char*));
                 a[1 + m] = NULL;
 
-                if (arg_init) {
-                        a[0] = arg_init;
+                FOREACH_STRING(init,
+                               "/usr/lib/systemd/systemd",
+                               "/lib/systemd/systemd",
+                               "/sbin/init") {
+                        a[0] = (char*) init;
                         execve(a[0], a, env_use);
-                        exec_target = arg_init;
-                } else {
-                        FOREACH_STRING(init,
-                                        "/usr/lib/systemd/systemd",
-                                        "/lib/systemd/systemd",
-                                        "/sbin/init") {
-                                a[0] = (char*) init;
-                                execve(a[0], a, env_use);
-                        }
-
-                        exec_target = "/usr/lib/systemd/systemd, /lib/systemd/systemd, /sbin/init";
                 }
+
+                exec_target = "/usr/lib/systemd/systemd, /lib/systemd/systemd, /sbin/init";
         } else if (!strv_isempty(arg_parameters)) {
                 const char *dollar_path;
 
@@ -4607,9 +4585,6 @@ static int merge_settings(Settings *settings, const char *path) {
                 strv_free_and_replace(arg_parameters, settings->parameters);
         }
 
-        if ((arg_settings_mask & SETTING_INIT) == 0 && settings->init)
-                free_and_replace(arg_init, settings->init);
-
         if ((arg_settings_mask & SETTING_EPHEMERAL) == 0 &&
             settings->ephemeral >= 0)
                 arg_ephemeral = settings->ephemeral;