diff --git a/src/cryptsetup/cryptsetup-generator.c b/src/cryptsetup/cryptsetup-generator.c
index 8a889e980a..8759a26148 100644
--- a/src/cryptsetup/cryptsetup-generator.c
+++ b/src/cryptsetup/cryptsetup-generator.c
@@ -13,7 +13,6 @@
 #include "hashmap.h"
 #include "id128-util.h"
 #include "log.h"
-#include "main-func.h"
 #include "mkdir.h"
 #include "parse-util.h"
 #include "path-util.h"
@@ -33,7 +32,7 @@ typedef struct crypto_device {
         bool create;
 } crypto_device;
 
-static const char *arg_dest = "/tmp";
+static const char *arg_dest = NULL;
 static bool arg_enabled = true;
 static bool arg_read_crypttab = true;
 static bool arg_whitelist = false;
@@ -580,16 +579,10 @@ static int add_proc_cmdline_devices(void) {
 DEFINE_PRIVATE_HASH_OPS_WITH_VALUE_DESTRUCTOR(crypt_device_hash_ops, char, string_hash_func, string_compare_func,
                                               crypto_device, crypt_device_free);
 
-static int run(int argc, char *argv[]) {
+static int run(const char *dest, const char *dest_early, const char *dest_late) {
         int r;
 
-        if (argc > 1 && argc != 4)
-                return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "This program takes three or no arguments.");
-
-        if (argc > 1)
-                arg_dest = argv[1];
-
-        log_setup_generator();
+        assert_se(arg_dest = dest);
 
         arg_disks = hashmap_new(&crypt_device_hash_ops);
         if (!arg_disks)
@@ -613,4 +606,4 @@ static int run(int argc, char *argv[]) {
         return 0;
 }
 
-DEFINE_MAIN_FUNCTION(run);
+DEFINE_MAIN_GENERATOR_FUNCTION(run);
diff --git a/src/debug-generator/debug-generator.c b/src/debug-generator/debug-generator.c
index 24bc4bd7e2..fa4ca57bbf 100644
--- a/src/debug-generator/debug-generator.c
+++ b/src/debug-generator/debug-generator.c
@@ -2,7 +2,6 @@
 
 #include "alloc-util.h"
 #include "generator.h"
-#include "main-func.h"
 #include "mkdir.h"
 #include "parse-util.h"
 #include "proc-cmdline.h"
@@ -12,8 +11,8 @@
 #include "unit-name.h"
 #include "util.h"
 
+static const char *arg_dest = NULL;
 static char *arg_default_unit = NULL;
-static const char *arg_dest = "/tmp";
 static char **arg_mask = NULL;
 static char **arg_wants = NULL;
 static bool arg_debug_shell = false;
@@ -142,17 +141,10 @@ static int generate_wants_symlinks(void) {
         return r;
 }
 
-static int run(int argc, char *argv[]) {
+static int run(const char *dest, const char *dest_early, const char *dest_late) {
         int r, q;
 
-        if (argc > 1 && argc != 4)
-                return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
-                                       "This program takes three or no arguments.");
-
-        if (argc > 1)
-                arg_dest = argv[2];
-
-        log_setup_generator();
+        assert_se(arg_dest = dest_early);
 
         r = proc_cmdline_parse(parse_proc_cmdline_item, NULL, PROC_CMDLINE_RD_STRICT | PROC_CMDLINE_STRIP_RD_PREFIX);
         if (r < 0)
@@ -170,4 +162,4 @@ static int run(int argc, char *argv[]) {
         return r < 0 ? r : q;
 }
 
-DEFINE_MAIN_FUNCTION(run);
+DEFINE_MAIN_GENERATOR_FUNCTION(run);
diff --git a/src/fstab-generator/fstab-generator.c b/src/fstab-generator/fstab-generator.c
index 85cc36d80d..616b42f33f 100644
--- a/src/fstab-generator/fstab-generator.c
+++ b/src/fstab-generator/fstab-generator.c
@@ -40,8 +40,8 @@ typedef enum MountpointFlags {
         GROWFS    = 1 << 4,
 } MountpointFlags;
 
-static const char *arg_dest = "/tmp";
-static const char *arg_dest_late = "/tmp";
+static const char *arg_dest = NULL;
+static const char *arg_dest_late = NULL;
 static bool arg_fstab_enabled = true;
 static char *arg_root_what = NULL;
 static char *arg_root_fstype = NULL;
@@ -539,7 +539,7 @@ static int parse_fstab(bool initrd) {
                 if (!what)
                         return log_oom();
 
-                if (is_device_path(what) && path_is_read_only_fs("sys") > 0) {
+                if (is_device_path(what) && path_is_read_only_fs("/sys") > 0) {
                         log_info("Running in a container, ignoring fstab device entry for %s.", what);
                         continue;
                 }
@@ -868,19 +868,11 @@ static int determine_root(void) {
         return 1;
 }
 
-static int run(int argc, char *argv[]) {
+static int run(const char *dest, const char *dest_early, const char *dest_late) {
         int r;
 
-        if (argc > 1 && argc != 4)
-                return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
-                                       "This program takes three or no arguments.");
-
-        if (argc > 1)
-                arg_dest = argv[1];
-        if (argc > 3)
-                arg_dest_late = argv[3];
-
-        log_setup_generator();
+        assert_se(arg_dest = dest);
+        assert_se(arg_dest_late = dest_late);
 
         r = proc_cmdline_parse(parse_proc_cmdline_item, NULL, 0);
         if (r < 0)
@@ -928,4 +920,4 @@ static int run(int argc, char *argv[]) {
         return r;
 }
 
-DEFINE_MAIN_FUNCTION(run);
+DEFINE_MAIN_GENERATOR_FUNCTION(run);
diff --git a/src/getty-generator/getty-generator.c b/src/getty-generator/getty-generator.c
index e2e07bca76..35501b61f5 100644
--- a/src/getty-generator/getty-generator.c
+++ b/src/getty-generator/getty-generator.c
@@ -13,13 +13,13 @@
 #include "mkdir.h"
 #include "path-util.h"
 #include "process-util.h"
-#include "string-util.h"
+#include "strv.h"
 #include "terminal-util.h"
 #include "unit-name.h"
 #include "util.h"
 #include "virt.h"
 
-static const char *arg_dest = "/tmp";
+static const char *arg_dest = NULL;
 
 static int add_symlink(const char *fservice, const char *tservice) {
         char *from, *to;
@@ -99,37 +99,21 @@ static int verify_tty(const char *name) {
         return 0;
 }
 
-int main(int argc, char *argv[]) {
-
-        static const char virtualization_consoles[] =
-                "hvc0\0"
-                "xvc0\0"
-                "hvsi0\0"
-                "sclp_line0\0"
-                "ttysclp0\0"
-                "3270!tty1\0";
-
+static int run(const char *dest, const char *dest_early, const char *dest_late) {
         _cleanup_free_ char *active = NULL;
         const char *j;
         int r;
 
-        if (argc > 1 && argc != 4) {
-                log_error("This program takes three or no arguments.");
-                return EXIT_FAILURE;
-        }
-
-        if (argc > 1)
-                arg_dest = argv[1];
-
-        log_setup_generator();
+        assert_se(arg_dest = dest);
 
         if (detect_container() > 0) {
                 _cleanup_free_ char *container_ttys = NULL;
 
                 log_debug("Automatically adding console shell.");
 
-                if (add_symlink("console-getty.service", "console-getty.service") < 0)
-                        return EXIT_FAILURE;
+                r = add_symlink("console-getty.service", "console-getty.service");
+                if (r < 0)
+                        return r;
 
                 /* When $container_ttys is set for PID 1, spawn
                  * gettys on all ptys named therein. Note that despite
@@ -157,13 +141,14 @@ int main(int argc, char *argv[]) {
                                 if (!t)
                                         continue;
 
-                                if (add_container_getty(t) < 0)
-                                        return EXIT_FAILURE;
+                                r = add_container_getty(t);
+                                if (r < 0)
+                                        return r;
                         }
                 }
 
                 /* Don't add any further magic if we are in a container */
-                return EXIT_SUCCESS;
+                return 0;
         }
 
         if (read_one_line_file("/sys/class/tty/console/active", &active) >= 0) {
@@ -176,10 +161,8 @@ int main(int argc, char *argv[]) {
                         _cleanup_free_ char *tty = NULL;
 
                         tty = strndup(word, l);
-                        if (!tty) {
-                                log_oom();
-                                return EXIT_FAILURE;
-                        }
+                        if (!tty)
+                                return log_oom();
 
                         /* We assume that gettys on virtual terminals are
                          * started via manual configuration and do this magic
@@ -191,23 +174,33 @@ int main(int argc, char *argv[]) {
                         if (verify_tty(tty) < 0)
                                 continue;
 
-                        if (add_serial_getty(tty) < 0)
-                                return EXIT_FAILURE;
+                        r = add_serial_getty(tty);
+                        if (r < 0)
+                                return r;
                 }
         }
 
         /* Automatically add in a serial getty on the first
          * virtualizer console */
-        NULSTR_FOREACH(j, virtualization_consoles) {
-                char *p;
+        FOREACH_STRING(j,
+                       "hvc0",
+                       "xvc0",
+                       "hvsi0",
+                       "sclp_line0",
+                       "ttysclp0",
+                       "3270!tty1") {
+                const char *p;
 
                 p = strjoina("/sys/class/tty/", j);
                 if (access(p, F_OK) < 0)
                         continue;
 
-                if (add_serial_getty(j) < 0)
-                        return EXIT_FAILURE;
+                r = add_serial_getty(j);
+                if (r < 0)
+                        return r;
         }
 
-        return EXIT_SUCCESS;
+        return 0;
 }
+
+DEFINE_MAIN_GENERATOR_FUNCTION(run);
diff --git a/src/gpt-auto-generator/gpt-auto-generator.c b/src/gpt-auto-generator/gpt-auto-generator.c
index d188927398..a6d7bcc755 100644
--- a/src/gpt-auto-generator/gpt-auto-generator.c
+++ b/src/gpt-auto-generator/gpt-auto-generator.c
@@ -36,7 +36,7 @@
 #include "util.h"
 #include "virt.h"
 
-static const char *arg_dest = "/tmp";
+static const char *arg_dest = NULL;
 static bool arg_enabled = true;
 static bool arg_root_enabled = true;
 static bool arg_root_rw = false;
@@ -668,22 +668,14 @@ static int add_mounts(void) {
         return enumerate_partitions(devno);
 }
 
-int main(int argc, char *argv[]) {
+static int run(const char *dest, const char *dest_early, const char *dest_late) {
         int r, k;
 
-        if (argc > 1 && argc != 4) {
-                log_error("This program takes three or no arguments.");
-                return EXIT_FAILURE;
-        }
-
-        if (argc > 1)
-                arg_dest = argv[3];
-
-        log_setup_generator();
+        assert_se(arg_dest = dest_late);
 
         if (detect_container() > 0) {
                 log_debug("In a container, exiting.");
-                return EXIT_SUCCESS;
+                return 0;
         }
 
         r = proc_cmdline_parse(parse_proc_cmdline_item, NULL, 0);
@@ -692,19 +684,19 @@ int main(int argc, char *argv[]) {
 
         if (!arg_enabled) {
                 log_debug("Disabled, exiting.");
-                return EXIT_SUCCESS;
+                return 0;
         }
 
         if (arg_root_enabled)
                 r = add_root_mount();
-        else
-                r = 0;
 
         if (!in_initrd()) {
                 k = add_mounts();
-                if (k < 0)
+                if (r >= 0)
                         r = k;
         }
 
-        return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
+        return r;
 }
+
+DEFINE_MAIN_GENERATOR_FUNCTION(run);
diff --git a/src/rc-local-generator/rc-local-generator.c b/src/rc-local-generator/rc-local-generator.c
index cd5510bf12..7a3948e92d 100644
--- a/src/rc-local-generator/rc-local-generator.c
+++ b/src/rc-local-generator/rc-local-generator.c
@@ -6,12 +6,11 @@
 
 #include "generator.h"
 #include "log.h"
-#include "main-func.h"
 #include "mkdir.h"
 #include "string-util.h"
 #include "util.h"
 
-static const char *arg_dest = "/tmp";
+static const char *arg_dest = NULL;
 
 /* So you are reading this, and might wonder: why is this implemented as a generator rather than as a plain, statically
  * enabled service that carries appropriate ConditionFileIsExecutable= lines? The answer is this: conditions bypass
@@ -55,16 +54,10 @@ static int check_executable(const char *path) {
         return 0;
 }
 
-static int run(int argc, char *argv[]) {
+static int run(const char *dest, const char *dest_early, const char *dest_late) {
         int r = 0, k = 0;
 
-        log_setup_generator();
-
-        if (argc > 1 && argc != 4)
-                return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "This program takes three or no arguments.");
-
-        if (argc > 1)
-                arg_dest = argv[1];
+        assert_se(arg_dest = dest);
 
         if (check_executable(RC_LOCAL_SCRIPT_PATH_START) >= 0) {
                 log_debug("Automatically adding rc-local.service.");
@@ -81,4 +74,4 @@ static int run(int argc, char *argv[]) {
         return r < 0 ? r : k;
 }
 
-DEFINE_MAIN_FUNCTION(run);
+DEFINE_MAIN_GENERATOR_FUNCTION(run);
diff --git a/src/run-generator/run-generator.c b/src/run-generator/run-generator.c
index 243a426cda..a5dfac01d4 100644
--- a/src/run-generator/run-generator.c
+++ b/src/run-generator/run-generator.c
@@ -5,13 +5,12 @@
 #include "fd-util.h"
 #include "fileio.h"
 #include "generator.h"
-#include "main-func.h"
 #include "mkdir.h"
 #include "proc-cmdline.h"
 #include "specifier.h"
 #include "strv.h"
 
-static const char *arg_dest = "/tmp";
+static const char *arg_dest = NULL;
 static char **arg_commands = NULL;
 static char *arg_success_action = NULL;
 static char *arg_failure_action = NULL;
@@ -122,20 +121,10 @@ static int generate(void) {
         return 0;
 }
 
-static int run(int argc, char *argv[]) {
+static int run(const char *dest, const char *dest_early, const char *dest_late) {
         int r;
 
-        log_setup_generator();
-
-        if (argc > 1 && argc != 4) {
-                log_error("This program takes three or no arguments.");
-                return -EINVAL;
-        }
-
-        if (argc > 1)
-                arg_dest = argv[1];
-
-        umask(0022);
+        assert_se(arg_dest = dest);
 
         r = proc_cmdline_parse(parse, NULL, PROC_CMDLINE_RD_STRICT|PROC_CMDLINE_STRIP_RD_PREFIX);
         if (r < 0)
@@ -144,4 +133,4 @@ static int run(int argc, char *argv[]) {
         return generate();
 }
 
-DEFINE_MAIN_FUNCTION(run);
+DEFINE_MAIN_GENERATOR_FUNCTION(run);
diff --git a/src/shared/generator.h b/src/shared/generator.h
index f1a055401a..5a1c1e32f7 100644
--- a/src/shared/generator.h
+++ b/src/shared/generator.h
@@ -3,6 +3,8 @@
 
 #include <stdio.h>
 
+#include "main-func.h"
+
 int generator_open_unit_file(
         const char *dest,
         const char *source,
@@ -49,3 +51,17 @@ int generator_hook_up_growfs(
         const char *target);
 
 void log_setup_generator(void);
+
+/* Similar to DEFINE_MAIN_FUNCTION, but initializes logging and assigns positional arguments. */
+#define DEFINE_MAIN_GENERATOR_FUNCTION(impl)                            \
+        _DEFINE_MAIN_FUNCTION(                                          \
+                ({                                                      \
+                        log_setup_generator();                          \
+                        if (argc > 1 && argc != 4)                      \
+                                return log_error_errno(SYNTHETIC_ERRNO(EINVAL), \
+                                                       "This program takes zero or three arguments."); \
+                }),                                                     \
+                impl(argc > 1 ? argv[1] : "/tmp",                       \
+                     argc > 1 ? argv[2] : "/tmp",                       \
+                     argc > 1 ? argv[3] : "/tmp"),                      \
+                r < 0 ? EXIT_FAILURE : EXIT_SUCCESS)
diff --git a/src/shared/main-func.h b/src/shared/main-func.h
index ab6b272117..3c182e802b 100644
--- a/src/shared/main-func.h
+++ b/src/shared/main-func.h
@@ -9,10 +9,11 @@
 #include "spawn-polkit-agent.h"
 #include "static-destruct.h"
 
-#define _DEFINE_MAIN_FUNCTION(impl, ret)                                \
+#define _DEFINE_MAIN_FUNCTION(intro, impl, ret)                         \
         int main(int argc, char *argv[]) {                              \
                 int r;                                                  \
-                r = impl(argc, argv);                                   \
+                intro;                                                  \
+                r = impl;                                               \
                 static_destruct();                                      \
                 ask_password_agent_close();                             \
                 polkit_agent_close();                                   \
@@ -24,10 +25,10 @@
 /* Negative return values from impl are mapped to EXIT_FAILURE, and
  * everything else means success! */
 #define DEFINE_MAIN_FUNCTION(impl)                                      \
-        _DEFINE_MAIN_FUNCTION(impl, r < 0 ? EXIT_FAILURE : EXIT_SUCCESS)
+        _DEFINE_MAIN_FUNCTION(,impl(argc, argv), r < 0 ? EXIT_FAILURE : EXIT_SUCCESS)
 
 /* Zero is mapped to EXIT_SUCCESS, negative values are mapped to EXIT_FAILURE,
  * and postive values are propagated.
  * Note: "true" means failure! */
 #define DEFINE_MAIN_FUNCTION_WITH_POSITIVE_FAILURE(impl)                \
-        _DEFINE_MAIN_FUNCTION(impl, r < 0 ? EXIT_FAILURE : r)
+        _DEFINE_MAIN_FUNCTION(,impl(argc, argv), r < 0 ? EXIT_FAILURE : r)
diff --git a/src/system-update-generator/system-update-generator.c b/src/system-update-generator/system-update-generator.c
index 06062e4510..77e265d710 100644
--- a/src/system-update-generator/system-update-generator.c
+++ b/src/system-update-generator/system-update-generator.c
@@ -15,7 +15,7 @@
  * Implements the logic described in systemd.offline-updates(7).
  */
 
-static const char *arg_dest = "/tmp";
+static const char *arg_dest = NULL;
 
 static int generate_symlink(void) {
         const char *p = NULL;
@@ -51,26 +51,20 @@ static int parse_proc_cmdline_item(const char *key, const char *value, void *dat
         return 0;
 }
 
-int main(int argc, char *argv[]) {
-        int r, k;
+static int run(const char *dest, const char *dest_early, const char *dest_late) {
+        int r;
 
-        if (argc > 1 && argc != 4) {
-                log_error("This program takes three or no arguments.");
-                return EXIT_FAILURE;
-        }
-
-        if (argc > 1)
-                arg_dest = argv[2];
-
-        log_setup_generator();
+        assert_se(arg_dest = dest_early);
 
         r = generate_symlink();
+        if (r < 0)
+                return r;
 
-        if (r > 0) {
-                k = proc_cmdline_parse(parse_proc_cmdline_item, NULL, 0);
-                if (k < 0)
-                        log_warning_errno(k, "Failed to parse kernel command line, ignoring: %m");
-        }
+        r = proc_cmdline_parse(parse_proc_cmdline_item, NULL, 0);
+        if (r < 0)
+                log_warning_errno(r, "Failed to parse kernel command line, ignoring: %m");
 
-        return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
+        return 0;
 }
+
+DEFINE_MAIN_GENERATOR_FUNCTION(run);
diff --git a/src/sysv-generator/sysv-generator.c b/src/sysv-generator/sysv-generator.c
index c4acdc4a50..514b6e0169 100644
--- a/src/sysv-generator/sysv-generator.c
+++ b/src/sysv-generator/sysv-generator.c
@@ -42,7 +42,7 @@ static const struct {
          * means they are shut down anyway at system power off if running. */
 };
 
-static const char *arg_dest = "/tmp";
+static const char *arg_dest = NULL;
 
 typedef struct SysvStub {
         char *name;
@@ -917,22 +917,14 @@ finish:
         return r;
 }
 
-static int run(int argc, char *argv[]) {
+static int run(const char *dest, const char *dest_early, const char *dest_late) {
         _cleanup_(free_sysvstub_hashmapp) Hashmap *all_services = NULL;
         _cleanup_(lookup_paths_free) LookupPaths lp = {};
         SysvStub *service;
         Iterator j;
         int r;
 
-        log_setup_generator();
-
-        if (argc > 1 && argc != 4) {
-                log_error("This program takes three or no arguments.");
-                return -EINVAL;
-        }
-
-        if (argc > 1)
-                arg_dest = argv[3];
+        assert_se(arg_dest = dest_late);
 
         r = lookup_paths_init(&lp, UNIT_FILE_SYSTEM, LOOKUP_PATHS_EXCLUDE_GENERATED, NULL);
         if (r < 0)
@@ -961,4 +953,4 @@ static int run(int argc, char *argv[]) {
         return 0;
 }
 
-DEFINE_MAIN_FUNCTION(run);
+DEFINE_MAIN_GENERATOR_FUNCTION(run);
diff --git a/src/veritysetup/veritysetup-generator.c b/src/veritysetup/veritysetup-generator.c
index 0f5830a6e2..65a4e7b0fd 100644
--- a/src/veritysetup/veritysetup-generator.c
+++ b/src/veritysetup/veritysetup-generator.c
@@ -204,16 +204,10 @@ static int determine_devices(void) {
         return 1;
 }
 
-static int run(int argc, char *argv[]) {
+static int run(const char *dest, const char *dest_early, const char *dest_late) {
         int r;
 
-        if (argc > 1 && argc != 4)
-                return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "This program takes three or no arguments.");
-
-        if (argc > 1)
-                arg_dest = argv[1];
-
-        log_setup_generator();
+        assert_se(arg_dest = dest);
 
         r = proc_cmdline_parse(parse_proc_cmdline_item, NULL, PROC_CMDLINE_STRIP_RD_PREFIX);
         if (r < 0)
@@ -229,11 +223,7 @@ static int run(int argc, char *argv[]) {
         if (r < 0)
                 return r;
 
-        r = create_device();
-        if (r < 0)
-                return r;
-
-        return 0;
+        return create_device();
 }
 
-DEFINE_MAIN_FUNCTION(run);
+DEFINE_MAIN_GENERATOR_FUNCTION(run);