util: rework strappenda(), and rename it strjoina()

After all it is now much more like strjoin() than strappend(). At the
same time, add support for NULL sentinels, even if they are normally not
necessary.

75 files changed, 248 insertions, 237 deletions

diff --git a/src/cgls/cgls.c b/src/cgls/cgls.c
index f400bccc0a..579e06de5b 100644
--- a/src/cgls/cgls.c
+++ b/src/cgls/cgls.c
@@ -203,7 +203,7 @@ int main(int argc, char *argv[]) {
                                 _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
                                 _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
 
-                                m = strappenda("/run/systemd/machines/", arg_machine);
+                                m = strjoina("/run/systemd/machines/", arg_machine);
                                 r = parse_env_file(m, NEWLINE, "SCOPE", &scope, NULL);
                                 if (r < 0) {
                                         log_error_errno(r, "Failed to get machine path: %m");
diff --git a/src/core/busname.c b/src/core/busname.c
index ca9ceb8c3c..bc3a2bcb78 100644
--- a/src/core/busname.c
+++ b/src/core/busname.c
@@ -205,7 +205,7 @@ static int busname_verify(BusName *n) {
                 return -EINVAL;
         }
 
-        e = strappenda(n->name, ".busname");
+        e = strjoina(n->name, ".busname");
         if (!unit_has_name(UNIT(n), e)) {
                 log_unit_error(UNIT(n)->id, "%s's Name= setting doesn't match unit name. Refusing.", UNIT(n)->id);
                 return -EINVAL;
diff --git a/src/core/dbus-cgroup.c b/src/core/dbus-cgroup.c
index db998345eb..4a9df06016 100644
--- a/src/core/dbus-cgroup.c
+++ b/src/core/dbus-cgroup.c
@@ -574,7 +574,7 @@ int bus_cgroup_set_property(
                         c->device_policy = p;
                         u->cgroup_realized_mask &= ~CGROUP_DEVICE;
 
-                        buf = strappenda("DevicePolicy=", policy);
+                        buf = strjoina("DevicePolicy=", policy);
                         unit_write_drop_in_private(u, mode, name, buf);
                 }
 
diff --git a/src/core/execute.c b/src/core/execute.c
index 19d3ec0da9..874cdc7efe 100644
--- a/src/core/execute.c
+++ b/src/core/execute.c
@@ -1582,9 +1582,9 @@ static int exec_child(
 
                 if (context->private_tmp && runtime) {
                         if (runtime->tmp_dir)
-                                tmp = strappenda(runtime->tmp_dir, "/tmp");
+                                tmp = strjoina(runtime->tmp_dir, "/tmp");
                         if (runtime->var_tmp_dir)
-                                var = strappenda(runtime->var_tmp_dir, "/tmp");
+                                var = strjoina(runtime->var_tmp_dir, "/tmp");
                 }
 
                 r = setup_namespace(
@@ -2588,7 +2588,7 @@ void exec_command_dump(ExecCommand *c, FILE *f, const char *prefix) {
         assert(f);
 
         prefix = strempty(prefix);
-        prefix2 = strappenda(prefix, "\t");
+        prefix2 = strjoina(prefix, "\t");
 
         cmd = exec_command_line(c->argv);
         fprintf(f,
diff --git a/src/core/machine-id-setup.c b/src/core/machine-id-setup.c
index 7e0aee6a75..d00a53246f 100644
--- a/src/core/machine-id-setup.c
+++ b/src/core/machine-id-setup.c
@@ -73,7 +73,7 @@ static int generate(char id[34], const char *root) {
         if (isempty(root))
                 dbus_machine_id = "/var/lib/dbus/machine-id";
         else
-                dbus_machine_id = strappenda(root, "/var/lib/dbus/machine-id");
+                dbus_machine_id = strjoina(root, "/var/lib/dbus/machine-id");
 
         /* First, try reading the D-Bus machine id, unless it is a symlink */
         fd = open(dbus_machine_id, O_RDONLY|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW);
@@ -199,7 +199,7 @@ int machine_id_commit(const char *root) {
         else {
                 char *x;
 
-                x = strappenda(root, "/etc/machine-id");
+                x = strjoina(root, "/etc/machine-id");
                 etc_machine_id = path_kill_slashes(x);
         }
 
@@ -281,10 +281,10 @@ int machine_id_setup(const char *root) {
         } else {
                 char *x;
 
-                x = strappenda(root, "/etc/machine-id");
+                x = strjoina(root, "/etc/machine-id");
                 etc_machine_id = path_kill_slashes(x);
 
-                x = strappenda(root, "/run/machine-id");
+                x = strjoina(root, "/run/machine-id");
                 run_machine_id = path_kill_slashes(x);
         }
 
diff --git a/src/core/manager.c b/src/core/manager.c
index 0b24cddc5f..5fba0043e4 100644
--- a/src/core/manager.c
+++ b/src/core/manager.c
@@ -2106,8 +2106,7 @@ void manager_send_unit_audit(Manager *m, Unit *u, int type, bool success) {
                 return;
         }
 
-        msg = strappenda("unit=", p);
-
+        msg = strjoina("unit=", p);
         if (audit_log_user_comm_message(audit_fd, type, msg, "systemd", NULL, NULL, NULL, success) < 0) {
                 if (errno == EPERM)
                         /* We aren't allowed to send audit messages?
diff --git a/src/core/mount.c b/src/core/mount.c
index a0b5fda9cb..f3977e62de 100644
--- a/src/core/mount.c
+++ b/src/core/mount.c
@@ -976,7 +976,7 @@ static void mount_enter_remounting(Mount *m) {
                 const char *o;
 
                 if (m->parameters_fragment.options)
-                        o = strappenda("remount,", m->parameters_fragment.options);
+                        o = strjoina("remount,", m->parameters_fragment.options);
                 else
                         o = "remount";
 
diff --git a/src/core/namespace.c b/src/core/namespace.c
index 4b8dbdd0d8..4fecd32363 100644
--- a/src/core/namespace.c
+++ b/src/core/namespace.c
@@ -157,24 +157,24 @@ static int mount_dev(BindMount *m) {
         if (!mkdtemp(temporary_mount))
                 return -errno;
 
-        dev = strappenda(temporary_mount, "/dev");
+        dev = strjoina(temporary_mount, "/dev");
         (void)mkdir(dev, 0755);
         if (mount("tmpfs", dev, "tmpfs", MS_NOSUID|MS_STRICTATIME, "mode=755") < 0) {
                 r = -errno;
                 goto fail;
         }
 
-        devpts = strappenda(temporary_mount, "/dev/pts");
+        devpts = strjoina(temporary_mount, "/dev/pts");
         (void)mkdir(devpts, 0755);
         if (mount("/dev/pts", devpts, NULL, MS_BIND, NULL) < 0) {
                 r = -errno;
                 goto fail;
         }
 
-        devptmx = strappenda(temporary_mount, "/dev/ptmx");
+        devptmx = strjoina(temporary_mount, "/dev/ptmx");
         symlink("pts/ptmx", devptmx);
 
-        devshm = strappenda(temporary_mount, "/dev/shm");
+        devshm = strjoina(temporary_mount, "/dev/shm");
         (void)mkdir(devshm, 01777);
         r = mount("/dev/shm", devshm, NULL, MS_BIND, NULL);
         if (r < 0) {
@@ -182,15 +182,15 @@ static int mount_dev(BindMount *m) {
                 goto fail;
         }
 
-        devmqueue = strappenda(temporary_mount, "/dev/mqueue");
+        devmqueue = strjoina(temporary_mount, "/dev/mqueue");
         (void)mkdir(devmqueue, 0755);
         mount("/dev/mqueue", devmqueue, NULL, MS_BIND, NULL);
 
-        devhugepages = strappenda(temporary_mount, "/dev/hugepages");
+        devhugepages = strjoina(temporary_mount, "/dev/hugepages");
         (void)mkdir(devhugepages, 0755);
         mount("/dev/hugepages", devhugepages, NULL, MS_BIND, NULL);
 
-        devlog = strappenda(temporary_mount, "/dev/log");
+        devlog = strjoina(temporary_mount, "/dev/log");
         symlink("/run/systemd/journal/dev-log", devlog);
 
         NULSTR_FOREACH(d, devnodes) {
@@ -280,7 +280,7 @@ static int mount_kdbus(BindMount *m) {
         if (!mkdtemp(temporary_mount))
                 return log_error_errno(errno, "Failed create temp dir: %m");
 
-        root = strappenda(temporary_mount, "/kdbus");
+        root = strjoina(temporary_mount, "/kdbus");
         (void)mkdir(root, 0755);
         if (mount("tmpfs", root, "tmpfs", MS_NOSUID|MS_STRICTATIME, "mode=777") < 0) {
                 r = -errno;
@@ -295,7 +295,7 @@ static int mount_kdbus(BindMount *m) {
                 goto fail;
         }
 
-        busnode = strappenda(root, "/bus");
+        busnode = strjoina(root, "/bus");
         if (mknod(busnode, (st.st_mode & ~07777) | 0600, st.st_rdev) < 0) {
                 log_error_errno(errno, "mknod() for %s failed: %m", busnode);
                 r = -errno;
@@ -566,7 +566,7 @@ static int setup_one_tmp_dir(const char *id, const char *prefix, char **path) {
         RUN_WITH_UMASK(0000) {
                 char *y;
 
-                y = strappenda(x, "/tmp");
+                y = strjoina(x, "/tmp");
 
                 if (mkdir(y, 0777 | S_ISVTX) < 0)
                         return -errno;
@@ -594,7 +594,7 @@ int setup_tmp_dirs(const char *id, char **tmp_dir, char **var_tmp_dir) {
         if (r < 0) {
                 char *t;
 
-                t = strappenda(a, "/tmp");
+                t = strjoina(a, "/tmp");
                 rmdir(t);
                 rmdir(a);
 
diff --git a/src/core/service.c b/src/core/service.c
index 15a2ed7f7e..15e29be149 100644
--- a/src/core/service.c
+++ b/src/core/service.c
@@ -562,7 +562,7 @@ static int service_add_extras(Service *s) {
                 if (r < 0)
                         return r;
 
-                n = strappenda(s->bus_name, ".busname");
+                n = strjoina(s->bus_name, ".busname");
                 r = unit_add_dependency_by_name(UNIT(s), UNIT_AFTER, n, NULL, true);
                 if (r < 0)
                         return r;
@@ -619,7 +619,7 @@ static void service_dump(Unit *u, FILE *f, const char *prefix) {
         assert(s);
 
         prefix = strempty(prefix);
-        prefix2 = strappenda(prefix, "\t");
+        prefix2 = strjoina(prefix, "\t");
 
         fprintf(f,
                 "%sService State: %s\n"
@@ -1123,7 +1123,7 @@ static int service_spawn(
         }
 
         if (is_control && UNIT(s)->cgroup_path) {
-                path = strappenda(UNIT(s)->cgroup_path, "/control");
+                path = strjoina(UNIT(s)->cgroup_path, "/control");
                 cg_create(SYSTEMD_CGROUP_CONTROLLER, path);
         } else
                 path = UNIT(s)->cgroup_path;
@@ -1489,7 +1489,7 @@ static void service_kill_control_processes(Service *s) {
         if (!UNIT(s)->cgroup_path)
                 return;
 
-        p = strappenda(UNIT(s)->cgroup_path, "/control");
+        p = strjoina(UNIT(s)->cgroup_path, "/control");
         cg_kill_recursive(SYSTEMD_CGROUP_CONTROLLER, p, SIGKILL, true, true, true, NULL);
 }
 
diff --git a/src/core/socket.c b/src/core/socket.c
index 85f7f16e15..d3dabc85f2 100644
--- a/src/core/socket.c
+++ b/src/core/socket.c
@@ -266,7 +266,7 @@ static int socket_add_device_link(Socket *s) {
         if (!s->bind_to_device || streq(s->bind_to_device, "lo"))
                 return 0;
 
-        t = strappenda("/sys/subsystem/net/devices/", s->bind_to_device);
+        t = strjoina("/sys/subsystem/net/devices/", s->bind_to_device);
         return unit_add_node_link(UNIT(s), t, false);
 }
 
@@ -473,7 +473,7 @@ static void socket_dump(Unit *u, FILE *f, const char *prefix) {
         assert(f);
 
         prefix = strempty(prefix);
-        prefix2 = strappenda(prefix, "\t");
+        prefix2 = strjoina(prefix, "\t");
 
         fprintf(f,
                 "%sSocket State: %s\n"
diff --git a/src/core/swap.c b/src/core/swap.c
index 4fbabda568..6997921fde 100644
--- a/src/core/swap.c
+++ b/src/core/swap.c
@@ -749,7 +749,7 @@ static void swap_enter_activating(Swap *s) {
                 if (streq(discard, "all"))
                         discard_arg = "--discard";
                 else
-                        discard_arg = strappenda("--discard=", discard);
+                        discard_arg = strjoina("--discard=", discard);
 
                 r = exec_command_append(s->control_command, discard_arg, NULL);
                 if (r < 0)
diff --git a/src/core/unit.c b/src/core/unit.c
index c3433b2c5d..2f95737da0 100644
--- a/src/core/unit.c
+++ b/src/core/unit.c
@@ -868,7 +868,7 @@ void unit_dump(Unit *u, FILE *f, const char *prefix) {
         assert(u->type >= 0);
 
         prefix = strempty(prefix);
-        prefix2 = strappenda(prefix, "\t");
+        prefix2 = strjoina(prefix, "\t");
 
         fprintf(f,
                 "%s-> Unit %s:\n"
diff --git a/src/cryptsetup/cryptsetup-generator.c b/src/cryptsetup/cryptsetup-generator.c
index 27b2360d24..05061c0704 100644
--- a/src/cryptsetup/cryptsetup-generator.c
+++ b/src/cryptsetup/cryptsetup-generator.c
@@ -183,7 +183,7 @@ static int create_disk(
         if (ferror(f))
                 return log_error_errno(errno, "Failed to write file %s: %m", p);
 
-        from = strappenda("../", n);
+        from = strjoina("../", n);
 
         if (!noauto) {
 
diff --git a/src/cryptsetup/cryptsetup.c b/src/cryptsetup/cryptsetup.c
index 26141a01b0..3f613d9b65 100644
--- a/src/cryptsetup/cryptsetup.c
+++ b/src/cryptsetup/cryptsetup.c
@@ -295,7 +295,7 @@ static int get_password(const char *name, usec_t until, bool accept_cached, char
         if (!escaped_name)
                 return log_oom();
 
-        id = strappenda("cryptsetup:", escaped_name);
+        id = strjoina("cryptsetup:", escaped_name);
 
         r = ask_password_auto(text, "drive-harddisk", id, until, accept_cached, passwords);
         if (r < 0)
@@ -309,7 +309,7 @@ static int get_password(const char *name, usec_t until, bool accept_cached, char
                 if (asprintf(&text, "Please enter passphrase for disk %s! (verification)", name) < 0)
                         return log_oom();
 
-                id = strappenda("cryptsetup-verification:", escaped_name);
+                id = strjoina("cryptsetup-verification:", escaped_name);
 
                 r = ask_password_auto(text, "drive-harddisk", id, until, false, &passwords2);
                 if (r < 0)
diff --git a/src/dbus1-generator/dbus1-generator.c b/src/dbus1-generator/dbus1-generator.c
index ca737e3d1b..2e08af2df2 100644
--- a/src/dbus1-generator/dbus1-generator.c
+++ b/src/dbus1-generator/dbus1-generator.c
@@ -164,7 +164,7 @@ static int add_dbus(const char *path, const char *fname, const char *type) {
         assert(path);
         assert(fname);
 
-        p = strappenda(path, "/", fname);
+        p = strjoina(path, "/", fname);
         r = config_parse(NULL, p, NULL,
                          "D-BUS Service\0",
                          config_item_table_lookup, table,
@@ -250,8 +250,8 @@ fail:
 static int link_busnames_target(const char *units) {
         const char *f, *t;
 
-        f = strappenda(units, "/" SPECIAL_BUSNAMES_TARGET);
-        t = strappenda(arg_dest, "/" SPECIAL_BASIC_TARGET ".wants/" SPECIAL_BUSNAMES_TARGET);
+        f = strjoina(units, "/" SPECIAL_BUSNAMES_TARGET);
+        t = strjoina(arg_dest, "/" SPECIAL_BASIC_TARGET ".wants/" SPECIAL_BUSNAMES_TARGET);
 
         mkdir_parents_label(t, 0755);
         if (symlink(f, t) < 0)
@@ -263,19 +263,19 @@ static int link_busnames_target(const char *units) {
 static int link_compatibility(const char *units) {
         const char *f, *t;
 
-        f = strappenda(units, "/systemd-bus-proxyd.socket");
-        t = strappenda(arg_dest, "/" SPECIAL_DBUS_SOCKET);
+        f = strjoina(units, "/systemd-bus-proxyd.socket");
+        t = strjoina(arg_dest, "/" SPECIAL_DBUS_SOCKET);
         mkdir_parents_label(t, 0755);
         if (symlink(f, t) < 0)
                 return log_error_errno(errno, "Failed to create symlink %s: %m", t);
 
-        f = strappenda(units, "/systemd-bus-proxyd.socket");
-        t = strappenda(arg_dest, "/" SPECIAL_SOCKETS_TARGET ".wants/systemd-bus-proxyd.socket");
+        f = strjoina(units, "/systemd-bus-proxyd.socket");
+        t = strjoina(arg_dest, "/" SPECIAL_SOCKETS_TARGET ".wants/systemd-bus-proxyd.socket");
         mkdir_parents_label(t, 0755);
         if (symlink(f, t) < 0)
                 return log_error_errno(errno, "Failed to create symlink %s: %m", t);
 
-        t = strappenda(arg_dest, "/" SPECIAL_DBUS_SERVICE);
+        t = strjoina(arg_dest, "/" SPECIAL_DBUS_SERVICE);
         if (symlink("/dev/null", t) < 0)
                 return log_error_errno(errno, "Failed to mask %s: %m", t);
 
diff --git a/src/efi-boot-generator/efi-boot-generator.c b/src/efi-boot-generator/efi-boot-generator.c
index 99a819fe37..b3ff3a8b78 100644
--- a/src/efi-boot-generator/efi-boot-generator.c
+++ b/src/efi-boot-generator/efi-boot-generator.c
@@ -84,7 +84,7 @@ int main(int argc, char *argv[]) {
                 return EXIT_FAILURE;
         }
 
-        name = strappenda(arg_dest, "/boot.mount");
+        name = strjoina(arg_dest, "/boot.mount");
         f = fopen(name, "wxe");
         if (!f) {
                 log_error_errno(errno, "Failed to create mount unit file %s: %m", name);
@@ -124,7 +124,7 @@ int main(int argc, char *argv[]) {
                 return EXIT_FAILURE;
         }
 
-        name = strappenda(arg_dest, "/boot.automount");
+        name = strjoina(arg_dest, "/boot.automount");
         fclose(f);
         f = fopen(name, "wxe");
         if (!f) {
@@ -144,7 +144,7 @@ int main(int argc, char *argv[]) {
                 return EXIT_FAILURE;
         }
 
-        name = strappenda(arg_dest, "/" SPECIAL_LOCAL_FS_TARGET ".wants/boot.automount");
+        name = strjoina(arg_dest, "/" SPECIAL_LOCAL_FS_TARGET ".wants/boot.automount");
         mkdir_parents(name, 0755);
 
         if (symlink("../boot.automount", name) < 0) {
diff --git a/src/firstboot/firstboot.c b/src/firstboot/firstboot.c
index a160c52fee..a765d6d219 100644
--- a/src/firstboot/firstboot.c
+++ b/src/firstboot/firstboot.c
@@ -50,7 +50,7 @@ static bool arg_copy_locale = false;
 static bool arg_copy_timezone = false;
 static bool arg_copy_root_password = false;
 
-#define prefix_roota(p) (arg_root ? (const char*) strappenda(arg_root, p) : (const char*) p)
+#define prefix_roota(p) (arg_root ? (const char*) strjoina(arg_root, p) : (const char*) p)
 
 static void clear_string(char *x) {
 
@@ -271,9 +271,9 @@ static int process_locale(void) {
                 return r;
 
         if (!isempty(arg_locale))
-                locales[i++] = strappenda("LANG=", arg_locale);
+                locales[i++] = strjoina("LANG=", arg_locale);
         if (!isempty(arg_locale_messages) && !streq(arg_locale_messages, arg_locale))
-                locales[i++] = strappenda("LC_MESSAGES=", arg_locale_messages);
+                locales[i++] = strjoina("LC_MESSAGES=", arg_locale_messages);
 
         if (i == 0)
                 return 0;
@@ -351,7 +351,7 @@ static int process_timezone(void) {
         if (isempty(arg_timezone))
                 return 0;
 
-        e = strappenda("../usr/share/zoneinfo/", arg_timezone);
+        e = strjoina("../usr/share/zoneinfo/", arg_timezone);
 
         mkdir_parents(etc_localtime, 0755);
         if (symlink(e, etc_localtime) < 0)
@@ -460,8 +460,8 @@ static int prompt_root_password(void) {
         print_welcome();
         putchar('\n');
 
-        msg1 = strappenda(draw_special_char(DRAW_TRIANGULAR_BULLET), " Please enter a new root password (empty to skip): ");
-        msg2 = strappenda(draw_special_char(DRAW_TRIANGULAR_BULLET), " Please enter new root password again: ");
+        msg1 = strjoina(draw_special_char(DRAW_TRIANGULAR_BULLET), " Please enter a new root password (empty to skip): ");
+        msg2 = strjoina(draw_special_char(DRAW_TRIANGULAR_BULLET), " Please enter new root password again: ");
 
         for (;;) {
                 _cleanup_free_ char *a = NULL, *b = NULL;
diff --git a/src/fstab-generator/fstab-generator.c b/src/fstab-generator/fstab-generator.c
index bc4c1556ca..5662b5fde1 100644
--- a/src/fstab-generator/fstab-generator.c
+++ b/src/fstab-generator/fstab-generator.c
@@ -404,7 +404,7 @@ static int add_root_mount(void) {
                 opts = arg_root_rw > 0 ? "rw" : "ro";
         else if (arg_root_rw >= 0 ||
                  !fstab_test_option(arg_root_options, "ro\0" "rw\0"))
-                opts = strappenda(arg_root_options, ",", arg_root_rw > 0 ? "rw" : "ro");
+                opts = strjoina(arg_root_options, ",", arg_root_rw > 0 ? "rw" : "ro");
         else
                 opts = arg_root_options;
 
@@ -461,7 +461,7 @@ static int add_usr_mount(void) {
         if (!arg_usr_options)
                 opts = arg_root_rw > 0 ? "rw" : "ro";
         else if (!fstab_test_option(arg_usr_options, "ro\0" "rw\0"))
-                opts = strappenda(arg_usr_options, ",", arg_root_rw > 0 ? "rw" : "ro");
+                opts = strjoina(arg_usr_options, ",", arg_root_rw > 0 ? "rw" : "ro");
         else
                 opts = arg_usr_options;
 
diff --git a/src/getty-generator/getty-generator.c b/src/getty-generator/getty-generator.c
index 931651e161..f8f5fb30c2 100644
--- a/src/getty-generator/getty-generator.c
+++ b/src/getty-generator/getty-generator.c
@@ -41,8 +41,8 @@ static int add_symlink(const char *fservice, const char *tservice) {
         assert(fservice);
         assert(tservice);
 
-        from = strappenda(SYSTEM_DATA_UNIT_PATH "/", fservice);
-        to = strappenda(arg_dest, "/getty.target.wants/", tservice);
+        from = strjoina(SYSTEM_DATA_UNIT_PATH "/", fservice);
+        to = strjoina(arg_dest, "/getty.target.wants/", tservice);
 
         mkdir_parents_label(to, 0755);
 
@@ -97,7 +97,7 @@ static int verify_tty(const char *name) {
          * friends. Let's check that and open the device and run
          * isatty() on it. */
 
-        p = strappenda("/dev/", name);
+        p = strjoina("/dev/", name);
 
         /* O_NONBLOCK is essential here, to make sure we don't wait
          * for DCD */
@@ -218,7 +218,7 @@ int main(int argc, char *argv[]) {
         NULSTR_FOREACH(j, virtualization_consoles) {
                 char *p;
 
-                p = strappenda("/sys/class/tty/", j);
+                p = strjoina("/sys/class/tty/", j);
                 if (access(p, F_OK) < 0)
                         continue;
 
diff --git a/src/gpt-auto-generator/gpt-auto-generator.c b/src/gpt-auto-generator/gpt-auto-generator.c
index 909fdda60a..5c58b58f8a 100644
--- a/src/gpt-auto-generator/gpt-auto-generator.c
+++ b/src/gpt-auto-generator/gpt-auto-generator.c
@@ -147,7 +147,7 @@ static int add_cryptsetup(const char *id, const char *what, bool rw, char **devi
         if (ferror(f))
                 return log_error_errno(errno, "Failed to write file %s: %m", p);
 
-        from = strappenda("../", n);
+        from = strjoina("../", n);
 
         to = strjoin(arg_dest, "/", d, ".wants/", n, NULL);
         if (!to)
diff --git a/src/import/curl-util.c b/src/import/curl-util.c
index 313b04b0b8..d390cfb1f3 100644
--- a/src/import/curl-util.c
+++ b/src/import/curl-util.c
@@ -303,7 +303,7 @@ int curl_glue_make(CURL **ret, const char *url, void *userdata) {
                 goto fail;
         }
 
-        useragent = strappenda(program_invocation_short_name, "/" PACKAGE_VERSION);
+        useragent = strjoina(program_invocation_short_name, "/" PACKAGE_VERSION);
         if (curl_easy_setopt(c, CURLOPT_USERAGENT, useragent) != CURLE_OK) {
                 r = -EIO;
                 goto fail;
diff --git a/src/import/import-common.c b/src/import/import-common.c
index e5531b89c5..2acf380f99 100644
--- a/src/import/import-common.c
+++ b/src/import/import-common.c
@@ -121,7 +121,7 @@ int import_make_local_copy(const char *final, const char *image_root, const char
         if (!image_root)
                 image_root = "/var/lib/machines";
 
-        p = strappenda(image_root, "/", local);
+        p = strjoina(image_root, "/", local);
 
         if (force_local) {
                 (void) btrfs_subvol_remove(p);
@@ -309,7 +309,7 @@ int import_verify(
                 return -EBADMSG;
         }
 
-        line = strappenda(main_job->checksum, " *", fn, "\n");
+        line = strjoina(main_job->checksum, " *", fn, "\n");
 
         p = memmem(checksum_job->payload,
                    checksum_job->payload_size,
diff --git a/src/import/import-dkr.c b/src/import/import-dkr.c
index a4ff6f43f0..fb72f6cee3 100644
--- a/src/import/import-dkr.c
+++ b/src/import/import-dkr.c
@@ -399,7 +399,7 @@ static int dkr_import_add_token(DkrImport *i, ImportJob *j) {
         assert(j);
 
         if (i->response_token)
-                t = strappenda("Authorization: Token ", i->response_token);
+                t = strjoina("Authorization: Token ", i->response_token);
         else
                 t = HEADER_TOKEN " true";
 
@@ -480,7 +480,7 @@ static int dkr_import_job_on_open_disk(ImportJob *j) {
         if (base) {
                 const char *base_path;
 
-                base_path = strappenda(i->image_root, "/.dkr-", base);
+                base_path = strjoina(i->image_root, "/.dkr-", base);
                 r = btrfs_subvol_snapshot(base_path, i->temp_path, false, true);
         } else
                 r = btrfs_subvol_make(i->temp_path);
@@ -549,7 +549,7 @@ static int dkr_import_pull_layer(DkrImport *i) {
         i->final_path = path;
         path = NULL;
 
-        url = strappenda(PROTOCOL_PREFIX, i->response_registries[0], "/v1/images/", layer, "/layer");
+        url = strjoina(PROTOCOL_PREFIX, i->response_registries[0], "/v1/images/", layer, "/layer");
         r = import_job_new(&i->layer_job, url, i->glue, i);
         if (r < 0)
                 return log_error_errno(r, "Failed to allocate layer job: %m");
@@ -610,7 +610,7 @@ static void dkr_import_job_on_finished(ImportJob *j) {
                 log_info("Index lookup succeeded, directed to registry %s.", i->response_registries[0]);
                 dkr_import_report_progress(i, DKR_RESOLVING);
 
-                url = strappenda(PROTOCOL_PREFIX, i->response_registries[0], "/v1/repositories/", i->name, "/tags/", i->tag);
+                url = strjoina(PROTOCOL_PREFIX, i->response_registries[0], "/v1/repositories/", i->name, "/tags/", i->tag);
                 r = import_job_new(&i->tags_job, url, i->glue, i);
                 if (r < 0) {
                         log_error_errno(r, "Failed to allocate tags job: %m");
@@ -652,7 +652,7 @@ static void dkr_import_job_on_finished(ImportJob *j) {
                 log_info("Tag lookup succeeded, resolved to layer %s.", i->id);
                 dkr_import_report_progress(i, DKR_METADATA);
 
-                url = strappenda(PROTOCOL_PREFIX, i->response_registries[0], "/v1/images/", i->id, "/ancestry");
+                url = strjoina(PROTOCOL_PREFIX, i->response_registries[0], "/v1/images/", i->id, "/ancestry");
                 r = import_job_new(&i->ancestry_job, url, i->glue, i);
                 if (r < 0) {
                         log_error_errno(r, "Failed to allocate ancestry job: %m");
@@ -668,7 +668,7 @@ static void dkr_import_job_on_finished(ImportJob *j) {
                 i->ancestry_job->on_finished = dkr_import_job_on_finished;
                 i->ancestry_job->on_progress = dkr_import_job_on_progress;
 
-                url = strappenda(PROTOCOL_PREFIX, i->response_registries[0], "/v1/images/", i->id, "/json");
+                url = strjoina(PROTOCOL_PREFIX, i->response_registries[0], "/v1/images/", i->id, "/json");
                 r = import_job_new(&i->json_job, url, i->glue, i);
                 if (r < 0) {
                         log_error_errno(r, "Failed to allocate json job: %m");
@@ -873,7 +873,7 @@ int dkr_import_pull(DkrImport *i, const char *name, const char *tag, const char
         if (r < 0)
                 return r;
 
-        url = strappenda(i->index_url, "/v1/repositories/", name, "/images");
+        url = strjoina(i->index_url, "/v1/repositories/", name, "/images");
 
         r = import_job_new(&i->images_job, url, i->glue, i);
         if (r < 0)
diff --git a/src/import/import-raw.c b/src/import/import-raw.c
index 5c88cdb007..8d99f1085c 100644
--- a/src/import/import-raw.c
+++ b/src/import/import-raw.c
@@ -270,7 +270,7 @@ static int raw_import_make_local_copy(RawImport *i) {
                         return log_error_errno(errno, "Failed to seek to beginning of vendor image: %m");
         }
 
-        p = strappenda(i->image_root, "/", i->local, ".raw");
+        p = strjoina(i->image_root, "/", i->local, ".raw");
 
         if (i->force_local) {
                 (void) btrfs_subvol_remove(p);
diff --git a/src/journal-remote/journal-remote.c b/src/journal-remote/journal-remote.c
index f1c409cd94..8f32a9a988 100644
--- a/src/journal-remote/journal-remote.c
+++ b/src/journal-remote/journal-remote.c
@@ -885,7 +885,7 @@ static int remoteserver_init(RemoteServer *s,
         if (arg_url) {
                 const char *url, *hostname;
 
-                url = strappenda(arg_url, "/entries");
+                url = strjoina(arg_url, "/entries");
 
                 if (arg_getter) {
                         log_info("Spawning getter %s...", url);
diff --git a/src/journal-remote/microhttpd-util.c b/src/journal-remote/microhttpd-util.c
index 277e125403..34d93379da 100644
--- a/src/journal-remote/microhttpd-util.c
+++ b/src/journal-remote/microhttpd-util.c
@@ -38,7 +38,7 @@
 void microhttpd_logger(void *arg, const char *fmt, va_list ap) {
         char *f;
 
-        f = strappenda("microhttpd: ", fmt);
+        f = strjoina("microhttpd: ", fmt);
 
         DISABLE_WARNING_FORMAT_NONLITERAL;
         log_internalv(LOG_INFO, 0, NULL, 0, NULL, f, ap);
diff --git a/src/journal/coredump.c b/src/journal/coredump.c
index f6b95145d2..f7ba0191e1 100644
--- a/src/journal/coredump.c
+++ b/src/journal/coredump.c
@@ -634,11 +634,11 @@ int main(int argc, char* argv[]) {
                         goto finish;
                 }
 
-                core_unit = strappenda("COREDUMP_UNIT=", t);
+                core_unit = strjoina("COREDUMP_UNIT=", t);
                 free(t);
 
         } else if (cg_pid_get_user_unit(pid, &t) >= 0) {
-                core_unit = strappenda("COREDUMP_USER_UNIT=", t);
+                core_unit = strjoina("COREDUMP_USER_UNIT=", t);
                 free(t);
         }
 
@@ -650,20 +650,20 @@ int main(int argc, char* argv[]) {
         log_set_target(LOG_TARGET_JOURNAL_OR_KMSG);
         log_open();
 
-        core_pid = strappenda("COREDUMP_PID=", info[INFO_PID]);
+        core_pid = strjoina("COREDUMP_PID=", info[INFO_PID]);
         IOVEC_SET_STRING(iovec[j++], core_pid);
 
-        core_uid = strappenda("COREDUMP_UID=", info[INFO_UID]);
+        core_uid = strjoina("COREDUMP_UID=", info[INFO_UID]);
         IOVEC_SET_STRING(iovec[j++], core_uid);
 
-        core_gid = strappenda("COREDUMP_GID=", info[INFO_GID]);
+        core_gid = strjoina("COREDUMP_GID=", info[INFO_GID]);
         IOVEC_SET_STRING(iovec[j++], core_gid);
 
-        core_signal = strappenda("COREDUMP_SIGNAL=", info[INFO_SIGNAL]);
+        core_signal = strjoina("COREDUMP_SIGNAL=", info[INFO_SIGNAL]);
         IOVEC_SET_STRING(iovec[j++], core_signal);
 
         if (sd_pid_get_session(pid, &t) >= 0) {
-                core_session = strappenda("COREDUMP_SESSION=", t);
+                core_session = strjoina("COREDUMP_SESSION=", t);
                 free(t);
 
                 IOVEC_SET_STRING(iovec[j++], core_session);
@@ -677,31 +677,31 @@ int main(int argc, char* argv[]) {
         }
 
         if (sd_pid_get_slice(pid, &t) >= 0) {
-                core_slice = strappenda("COREDUMP_SLICE=", t);
+                core_slice = strjoina("COREDUMP_SLICE=", t);
                 free(t);
 
                 IOVEC_SET_STRING(iovec[j++], core_slice);
         }
 
         if (comm) {
-                core_comm = strappenda("COREDUMP_COMM=", comm);
+                core_comm = strjoina("COREDUMP_COMM=", comm);
                 IOVEC_SET_STRING(iovec[j++], core_comm);
         }
 
         if (exe) {
-                core_exe = strappenda("COREDUMP_EXE=", exe);
+                core_exe = strjoina("COREDUMP_EXE=", exe);
                 IOVEC_SET_STRING(iovec[j++], core_exe);
         }
 
         if (get_process_cmdline(pid, 0, false, &t) >= 0) {
-                core_cmdline = strappenda("COREDUMP_CMDLINE=", t);
+                core_cmdline = strjoina("COREDUMP_CMDLINE=", t);
                 free(t);
 
                 IOVEC_SET_STRING(iovec[j++], core_cmdline);
         }
 
         if (cg_pid_get_path_shifted(pid, NULL, &t) >= 0) {
-                core_cgroup = strappenda("COREDUMP_CGROUP=", t);
+                core_cgroup = strjoina("COREDUMP_CGROUP=", t);
                 free(t);
 
                 IOVEC_SET_STRING(iovec[j++], core_cgroup);
@@ -752,14 +752,14 @@ int main(int argc, char* argv[]) {
         }
 
         if (get_process_cwd(pid, &t) >= 0) {
-                core_cwd = strappenda("COREDUMP_CWD=", t);
+                core_cwd = strjoina("COREDUMP_CWD=", t);
                 free(t);
 
                 IOVEC_SET_STRING(iovec[j++], core_cwd);
         }
 
         if (get_process_root(pid, &t) >= 0) {
-                core_root = strappenda("COREDUMP_ROOT=", t);
+                core_root = strjoina("COREDUMP_ROOT=", t);
                 free(t);
 
                 IOVEC_SET_STRING(iovec[j++], core_root);
@@ -799,7 +799,7 @@ int main(int argc, char* argv[]) {
         if (r == 0) {
                 const char *coredump_filename;
 
-                coredump_filename = strappenda("COREDUMP_FILENAME=", filename);
+                coredump_filename = strjoina("COREDUMP_FILENAME=", filename);
                 IOVEC_SET_STRING(iovec[j++], coredump_filename);
         }
 
diff --git a/src/journal/journalctl.c b/src/journal/journalctl.c
index c17cf55c30..55c7786331 100644
--- a/src/journal/journalctl.c
+++ b/src/journal/journalctl.c
@@ -1269,7 +1269,7 @@ static int add_syslog_identifier(sd_journal *j) {
         STRV_FOREACH(i, arg_syslog_identifier) {
                 char *u;
 
-                u = strappenda("SYSLOG_IDENTIFIER=", *i);
+                u = strjoina("SYSLOG_IDENTIFIER=", *i);
                 r = sd_journal_add_match(j, u, 0);
                 if (r < 0)
                         return r;
diff --git a/src/journal/journald-server.c b/src/journal/journald-server.c
index aecf8596dc..7ee8174ea2 100644
--- a/src/journal/journald-server.c
+++ b/src/journal/journald-server.c
@@ -378,7 +378,7 @@ static void do_vacuum(
         if (!f)
                 return;
 
-        p = strappenda(path, id);
+        p = strjoina(path, id);
         r = journal_directory_vacuum(p, metrics->max_use, s->max_retention_usec, &s->oldest_file_usec, false);
         if (r < 0 && r != -ENOENT)
                 log_error_errno(r, "Failed to vacuum %s: %m", p);
@@ -589,28 +589,28 @@ static void dispatch_message_real(
 
                 r = get_process_comm(ucred->pid, &t);
                 if (r >= 0) {
-                        x = strappenda("_COMM=", t);
+                        x = strjoina("_COMM=", t);
                         free(t);
                         IOVEC_SET_STRING(iovec[n++], x);
                 }
 
                 r = get_process_exe(ucred->pid, &t);
                 if (r >= 0) {
-                        x = strappenda("_EXE=", t);
+                        x = strjoina("_EXE=", t);
                         free(t);
                         IOVEC_SET_STRING(iovec[n++], x);
                 }
 
                 r = get_process_cmdline(ucred->pid, 0, false, &t);
                 if (r >= 0) {
-                        x = strappenda("_CMDLINE=", t);
+                        x = strjoina("_CMDLINE=", t);
                         free(t);
                         IOVEC_SET_STRING(iovec[n++], x);
                 }
 
                 r = get_process_capeff(ucred->pid, &t);
                 if (r >= 0) {
-                        x = strappenda("_CAP_EFFECTIVE=", t);
+                        x = strjoina("_CAP_EFFECTIVE=", t);
                         free(t);
                         IOVEC_SET_STRING(iovec[n++], x);
                 }
@@ -633,12 +633,12 @@ static void dispatch_message_real(
                 if (r >= 0) {
                         char *session = NULL;
 
-                        x = strappenda("_SYSTEMD_CGROUP=", c);
+                        x = strjoina("_SYSTEMD_CGROUP=", c);
                         IOVEC_SET_STRING(iovec[n++], x);
 
                         r = cg_path_get_session(c, &t);
                         if (r >= 0) {
-                                session = strappenda("_SYSTEMD_SESSION=", t);
+                                session = strjoina("_SYSTEMD_SESSION=", t);
                                 free(t);
                                 IOVEC_SET_STRING(iovec[n++], session);
                         }
@@ -651,32 +651,32 @@ static void dispatch_message_real(
                         }
 
                         if (cg_path_get_unit(c, &t) >= 0) {
-                                x = strappenda("_SYSTEMD_UNIT=", t);
+                                x = strjoina("_SYSTEMD_UNIT=", t);
                                 free(t);
                                 IOVEC_SET_STRING(iovec[n++], x);
                         } else if (unit_id && !session) {
-                                x = strappenda("_SYSTEMD_UNIT=", unit_id);
+                                x = strjoina("_SYSTEMD_UNIT=", unit_id);
                                 IOVEC_SET_STRING(iovec[n++], x);
                         }
 
                         if (cg_path_get_user_unit(c, &t) >= 0) {
-                                x = strappenda("_SYSTEMD_USER_UNIT=", t);
+                                x = strjoina("_SYSTEMD_USER_UNIT=", t);
                                 free(t);
                                 IOVEC_SET_STRING(iovec[n++], x);
                         } else if (unit_id && session) {
-                                x = strappenda("_SYSTEMD_USER_UNIT=", unit_id);
+                                x = strjoina("_SYSTEMD_USER_UNIT=", unit_id);
                                 IOVEC_SET_STRING(iovec[n++], x);
                         }
 
                         if (cg_path_get_slice(c, &t) >= 0) {
-                                x = strappenda("_SYSTEMD_SLICE=", t);
+                                x = strjoina("_SYSTEMD_SLICE=", t);
                                 free(t);
                                 IOVEC_SET_STRING(iovec[n++], x);
                         }
 
                         free(c);
                 } else if (unit_id) {
-                        x = strappenda("_SYSTEMD_UNIT=", unit_id);
+                        x = strjoina("_SYSTEMD_UNIT=", unit_id);
                         IOVEC_SET_STRING(iovec[n++], x);
                 }
 
@@ -691,7 +691,7 @@ static void dispatch_message_real(
                                 security_context_t con;
 
                                 if (getpidcon(ucred->pid, &con) >= 0) {
-                                        x = strappenda("_SELINUX_CONTEXT=", con);
+                                        x = strjoina("_SELINUX_CONTEXT=", con);
 
                                         freecon(con);
                                         IOVEC_SET_STRING(iovec[n++], x);
@@ -717,21 +717,21 @@ static void dispatch_message_real(
 
                 r = get_process_comm(object_pid, &t);
                 if (r >= 0) {
-                        x = strappenda("OBJECT_COMM=", t);
+                        x = strjoina("OBJECT_COMM=", t);
                         free(t);
                         IOVEC_SET_STRING(iovec[n++], x);
                 }
 
                 r = get_process_exe(object_pid, &t);
                 if (r >= 0) {
-                        x = strappenda("OBJECT_EXE=", t);
+                        x = strjoina("OBJECT_EXE=", t);
                         free(t);
                         IOVEC_SET_STRING(iovec[n++], x);
                 }
 
                 r = get_process_cmdline(object_pid, 0, false, &t);
                 if (r >= 0) {
-                        x = strappenda("OBJECT_CMDLINE=", t);
+                        x = strjoina("OBJECT_CMDLINE=", t);
                         free(t);
                         IOVEC_SET_STRING(iovec[n++], x);
                 }
@@ -752,12 +752,12 @@ static void dispatch_message_real(
 
                 r = cg_pid_get_path_shifted(object_pid, s->cgroup_root, &c);
                 if (r >= 0) {
-                        x = strappenda("OBJECT_SYSTEMD_CGROUP=", c);
+                        x = strjoina("OBJECT_SYSTEMD_CGROUP=", c);
                         IOVEC_SET_STRING(iovec[n++], x);
 
                         r = cg_path_get_session(c, &t);
                         if (r >= 0) {
-                                x = strappenda("OBJECT_SYSTEMD_SESSION=", t);
+                                x = strjoina("OBJECT_SYSTEMD_SESSION=", t);
                                 free(t);
                                 IOVEC_SET_STRING(iovec[n++], x);
                         }
@@ -768,13 +768,13 @@ static void dispatch_message_real(
                         }
 
                         if (cg_path_get_unit(c, &t) >= 0) {
-                                x = strappenda("OBJECT_SYSTEMD_UNIT=", t);
+                                x = strjoina("OBJECT_SYSTEMD_UNIT=", t);
                                 free(t);
                                 IOVEC_SET_STRING(iovec[n++], x);
                         }
 
                         if (cg_path_get_user_unit(c, &t) >= 0) {
-                                x = strappenda("OBJECT_SYSTEMD_USER_UNIT=", t);
+                                x = strjoina("OBJECT_SYSTEMD_USER_UNIT=", t);
                                 free(t);
                                 IOVEC_SET_STRING(iovec[n++], x);
                         }
@@ -944,10 +944,10 @@ static int system_journal_open(Server *s, bool flush_requested) {
                 if (s->storage == STORAGE_PERSISTENT)
                         (void) mkdir("/var/log/journal/", 0755);
 
-                fn = strappenda("/var/log/journal/", ids);
+                fn = strjoina("/var/log/journal/", ids);
                 (void) mkdir(fn, 0755);
 
-                fn = strappenda(fn, "/system.journal");
+                fn = strjoina(fn, "/system.journal");
                 r = journal_file_open_reliably(fn, O_RDWR|O_CREAT, 0640, s->compress, s->seal, &s->system_metrics, s->mmap, NULL, &s->system_journal);
 
                 if (r >= 0)
diff --git a/src/journal/journald-syslog.c b/src/journal/journald-syslog.c
index ba6e3316d6..355f6e6a4b 100644
--- a/src/journal/journald-syslog.c
+++ b/src/journal/journald-syslog.c
@@ -356,18 +356,18 @@ void server_process_syslog_message(
         }
 
         if (identifier) {
-                syslog_identifier = strappenda("SYSLOG_IDENTIFIER=", identifier);
+                syslog_identifier = strjoina("SYSLOG_IDENTIFIER=", identifier);
                 if (syslog_identifier)
                         IOVEC_SET_STRING(iovec[n++], syslog_identifier);
         }
 
         if (pid) {
-                syslog_pid = strappenda("SYSLOG_PID=", pid);
+                syslog_pid = strjoina("SYSLOG_PID=", pid);
                 if (syslog_pid)
                         IOVEC_SET_STRING(iovec[n++], syslog_pid);
         }
 
-        message = strappenda("MESSAGE=", buf);
+        message = strjoina("MESSAGE=", buf);
         if (message)
                 IOVEC_SET_STRING(iovec[n++], message);
 
diff --git a/src/journal/sd-journal.c b/src/journal/sd-journal.c
index 9dea5470be..ecf47fda3d 100644
--- a/src/journal/sd-journal.c
+++ b/src/journal/sd-journal.c
@@ -1155,9 +1155,9 @@ static void check_network(sd_journal *j, int fd) {
 static bool file_has_type_prefix(const char *prefix, const char *filename) {
         const char *full, *tilded, *atted;
 
-        full = strappenda(prefix, ".journal");
-        tilded = strappenda(full, "~");
-        atted = strappenda(prefix, "@");
+        full = strjoina(prefix, ".journal");
+        tilded = strjoina(full, "~");
+        atted = strjoina(prefix, "@");
 
         return streq(filename, full) ||
                streq(filename, tilded) ||
@@ -1399,7 +1399,7 @@ static int add_root_directory(sd_journal *j, const char *p) {
                 return -EINVAL;
 
         if (j->prefix)
-                p = strappenda(j->prefix, p);
+                p = strjoina(j->prefix, p);
 
         d = opendir(p);
         if (!d)
@@ -1643,7 +1643,7 @@ _public_ int sd_journal_open_container(sd_journal **ret, const char *machine, in
         assert_return((flags & ~(SD_JOURNAL_LOCAL_ONLY|SD_JOURNAL_SYSTEM)) == 0, -EINVAL);
         assert_return(machine_name_is_valid(machine), -EINVAL);
 
-        p = strappenda("/run/systemd/machines/", machine);
+        p = strjoina("/run/systemd/machines/", machine);
         r = parse_env_file(p, NEWLINE, "ROOT", &root, "CLASS", &class, NULL);
         if (r == -ENOENT)
                 return -EHOSTDOWN;
diff --git a/src/libsystemd-terminal/idev-keyboard.c b/src/libsystemd-terminal/idev-keyboard.c
index def8ea5ebe..6ee3d8150c 100644
--- a/src/libsystemd-terminal/idev-keyboard.c
+++ b/src/libsystemd-terminal/idev-keyboard.c
@@ -631,7 +631,7 @@ idev_device *idev_find_keyboard(idev_session *s, const char *name) {
         assert_return(s, NULL);
         assert_return(name, NULL);
 
-        kname = strappenda("keyboard/", name);
+        kname = strjoina("keyboard/", name);
         return hashmap_get(s->device_map, kname);
 }
 
@@ -793,7 +793,7 @@ int idev_keyboard_new(idev_device **out, idev_session *s, const char *name) {
         if (r < 0)
                 return r;
 
-        kname = strappenda("keyboard/", name);
+        kname = strjoina("keyboard/", name);
         r = idev_device_add(d, kname);
         if (r < 0)
                 return r;
diff --git a/src/libsystemd/sd-bus/bus-control.c b/src/libsystemd/sd-bus/bus-control.c
index 8d12c258f7..ac27df8691 100644
--- a/src/libsystemd/sd-bus/bus-control.c
+++ b/src/libsystemd/sd-bus/bus-control.c
@@ -1359,7 +1359,7 @@ int bus_add_match_internal_kernel(
 
 #define internal_match(bus, m)                                          \
         ((bus)->hello_flags & KDBUS_HELLO_MONITOR                       \
-         ? (isempty(m) ? "eavesdrop='true'" : strappenda((m), ",eavesdrop='true'")) \
+         ? (isempty(m) ? "eavesdrop='true'" : strjoina((m), ",eavesdrop='true'")) \
          : (m))
 
 static int bus_add_match_internal_dbus1(
diff --git a/src/libsystemd/sd-bus/bus-dump.c b/src/libsystemd/sd-bus/bus-dump.c
index e27d8027de..7181639645 100644
--- a/src/libsystemd/sd-bus/bus-dump.c
+++ b/src/libsystemd/sd-bus/bus-dump.c
@@ -354,7 +354,7 @@ int bus_creds_dump(sd_bus_creds *c, FILE *f, bool terse) {
                 color = ansi_highlight();
 
                 off = ansi_highlight_off();
-                suffix = strappenda(off, "\n");
+                suffix = strjoina(off, "\n");
         }
 
         if (c->mask & SD_BUS_CREDS_PID)
diff --git a/src/libsystemd/sd-bus/busctl.c b/src/libsystemd/sd-bus/busctl.c
index f0bc2a76a5..d3c1772019 100644
--- a/src/libsystemd/sd-bus/busctl.c
+++ b/src/libsystemd/sd-bus/busctl.c
@@ -256,8 +256,8 @@ static void print_subtree(const char *prefix, const char *path, char **l) {
                 l++;
         }
 
-        vertical = strappenda(prefix, draw_special_char(DRAW_TREE_VERTICAL));
-        space = strappenda(prefix, draw_special_char(DRAW_TREE_SPACE));
+        vertical = strjoina(prefix, draw_special_char(DRAW_TREE_VERTICAL));
+        space = strjoina(prefix, draw_special_char(DRAW_TREE_SPACE));
 
         for (;;) {
                 bool has_more = false;
diff --git a/src/libsystemd/sd-bus/sd-bus.c b/src/libsystemd/sd-bus/sd-bus.c
index 125b302c95..1bf77e46fb 100644
--- a/src/libsystemd/sd-bus/sd-bus.c
+++ b/src/libsystemd/sd-bus/sd-bus.c
@@ -1286,7 +1286,7 @@ int bus_set_address_system_remote(sd_bus *b, const char *host) {
                         if (!e)
                                 return -ENOMEM;
 
-                        c = strappenda(",argv4=--machine=", m);
+                        c = strjoina(",argv4=--machine=", m);
                 }
         }
 
diff --git a/src/libsystemd/sd-login/sd-login.c b/src/libsystemd/sd-login/sd-login.c
index c72d23ed53..c171405a65 100644
--- a/src/libsystemd/sd-login/sd-login.c
+++ b/src/libsystemd/sd-login/sd-login.c
@@ -791,7 +791,7 @@ _public_ int sd_machine_get_class(const char *machine, char **class) {
         assert_return(machine_name_is_valid(machine), -EINVAL);
         assert_return(class, -EINVAL);
 
-        p = strappenda("/run/systemd/machines/", machine);
+        p = strjoina("/run/systemd/machines/", machine);
         r = parse_env_file(p, NEWLINE, "CLASS", &c, NULL);
         if (r < 0)
                 return r;
@@ -814,7 +814,7 @@ _public_ int sd_machine_get_ifindices(const char *machine, int **ifindices) {
         assert_return(machine_name_is_valid(machine), -EINVAL);
         assert_return(ifindices, -EINVAL);
 
-        p = strappenda("/run/systemd/machines/", machine);
+        p = strjoina("/run/systemd/machines/", machine);
         r = parse_env_file(p, NEWLINE, "NETIF", &netif, NULL);
         if (r < 0)
                 return r;
diff --git a/src/libudev/libudev-device.c b/src/libudev/libudev-device.c
index d5206aa804..9863901a33 100644
--- a/src/libudev/libudev-device.c
+++ b/src/libudev/libudev-device.c
@@ -1936,7 +1936,7 @@ int udev_device_rename(struct udev_device *udev_device, const char *name)
         if (!dirname)
                 return -ENOMEM;
 
-        new_syspath = strappenda(dirname, "/", name);
+        new_syspath = strjoina(dirname, "/", name);
 
         r = udev_device_set_syspath(udev_device, new_syspath);
         if (r < 0)
diff --git a/src/locale/localed.c b/src/locale/localed.c
index 529a9abfd6..ed763c36f6 100644
--- a/src/locale/localed.c
+++ b/src/locale/localed.c
@@ -1011,7 +1011,7 @@ static int method_set_vc_keyboard(sd_bus *bus, sd_bus_message *m, void *userdata
 static void log_xkb(struct xkb_context *ctx, enum xkb_log_level lvl, const char *format, va_list args) {
         const char *fmt;
 
-        fmt = strappenda("libxkbcommon: ", format);
+        fmt = strjoina("libxkbcommon: ", format);
         log_internalv(LOG_DEBUG, 0, __FILE__, __LINE__, __func__, fmt, args);
 }
 
diff --git a/src/login/logind-button.c b/src/login/logind-button.c
index e22b106b3c..d7211e66ce 100644
--- a/src/login/logind-button.c
+++ b/src/login/logind-button.c
@@ -247,7 +247,7 @@ int button_open(Button *b) {
                 b->fd = -1;
         }
 
-        p = strappenda("/dev/input/", b->name);
+        p = strjoina("/dev/input/", b->name);
 
         b->fd = open(p, O_RDWR|O_CLOEXEC|O_NOCTTY|O_NONBLOCK);
         if (b->fd < 0)
diff --git a/src/login/logind-dbus.c b/src/login/logind-dbus.c
index c7c1559d50..8b0bafd49e 100644
--- a/src/login/logind-dbus.c
+++ b/src/login/logind-dbus.c
@@ -1136,7 +1136,7 @@ static int method_set_user_linger(sd_bus *bus, sd_bus_message *message, void *us
         if (!cc)
                 return -ENOMEM;
 
-        path = strappenda("/var/lib/systemd/linger/", cc);
+        path = strjoina("/var/lib/systemd/linger/", cc);
         if (b) {
                 User *u;
 
diff --git a/src/login/logind-user.c b/src/login/logind-user.c
index 928afd35e2..7b40ef5952 100644
--- a/src/login/logind-user.c
+++ b/src/login/logind-user.c
@@ -659,7 +659,7 @@ int user_check_linger_file(User *u) {
         if (!cc)
                 return -ENOMEM;
 
-        p = strappenda("/var/lib/systemd/linger/", cc);
+        p = strjoina("/var/lib/systemd/linger/", cc);
 
         return access(p, F_OK) >= 0;
 }
diff --git a/src/machine/machine.c b/src/machine/machine.c
index 6c01617cfb..223eb0f364 100644
--- a/src/machine/machine.c
+++ b/src/machine/machine.c
@@ -211,7 +211,7 @@ int machine_save(Machine *m) {
                 /* Create a symlink from the unit name to the machine
                  * name, so that we can quickly find the machine for
                  * each given unit */
-                sl = strappenda("/run/systemd/machines/unit:", m->unit);
+                sl = strjoina("/run/systemd/machines/unit:", m->unit);
                 symlink(m->name, sl);
         }
 
@@ -232,7 +232,7 @@ static void machine_unlink(Machine *m) {
 
                 char *sl;
 
-                sl = strappenda("/run/systemd/machines/unit:", m->unit);
+                sl = strjoina("/run/systemd/machines/unit:", m->unit);
                 unlink(sl);
         }
 
@@ -340,7 +340,7 @@ static int machine_start_scope(Machine *m, sd_bus_message *properties, sd_bus_er
                 if (!scope)
                         return log_oom();
 
-                description = strappenda(m->class == MACHINE_VM ? "Virtual Machine " : "Container ", m->name);
+                description = strjoina(m->class == MACHINE_VM ? "Virtual Machine " : "Container ", m->name);
 
                 r = manager_start_scope(m->manager, scope, m->leader, SPECIAL_MACHINE_SLICE, description, properties, error, &job);
                 if (r < 0) {
diff --git a/src/machine/machinectl.c b/src/machine/machinectl.c
index 06ae8bc0a8..16ce2f424b 100644
--- a/src/machine/machinectl.c
+++ b/src/machine/machinectl.c
@@ -1160,7 +1160,7 @@ static int bind_mount(int argc, char *argv[], void *userdata) {
                 return -EINVAL;
         }
 
-        p = strappenda("/run/systemd/nspawn/propagate/", argv[1], "/");
+        p = strjoina("/run/systemd/nspawn/propagate/", argv[1], "/");
         if (access(p, F_OK) < 0) {
                 log_error("Container does not allow propagation of mount points.");
                 return -ENOTSUP;
@@ -1198,7 +1198,7 @@ static int bind_mount(int argc, char *argv[], void *userdata) {
 
         /* Second, we mount the source directory to a directory inside
            of our MS_SLAVE playground. */
-        mount_tmp = strappenda(mount_slave, "/mount");
+        mount_tmp = strjoina(mount_slave, "/mount");
         if (mkdir(mount_tmp, 0700) < 0) {
                 r = log_error_errno(errno, "Failed to create temporary mount: %m");
                 goto finish;
@@ -1224,7 +1224,7 @@ static int bind_mount(int argc, char *argv[], void *userdata) {
          * directory. This way it will appear there read-only
          * right-away. */
 
-        mount_outside = strappenda("/run/systemd/nspawn/propagate/", argv[1], "/XXXXXX");
+        mount_outside = strjoina("/run/systemd/nspawn/propagate/", argv[1], "/XXXXXX");
         if (!mkdtemp(mount_outside)) {
                 r = log_error_errno(errno, "Cannot create propagation directory: %m");
                 goto finish;
@@ -1276,7 +1276,7 @@ static int bind_mount(int argc, char *argv[], void *userdata) {
                         mkdir_p(dest, 0755);
 
                 /* Fifth, move the mount to the right place inside */
-                mount_inside = strappenda("/run/systemd/nspawn/incoming/", basename(mount_outside));
+                mount_inside = strjoina("/run/systemd/nspawn/incoming/", basename(mount_outside));
                 if (mount(mount_inside, dest, NULL, MS_MOVE, NULL) < 0) {
                         log_error_errno(errno, "Failed to mount: %m");
                         _exit(EXIT_FAILURE);
@@ -1376,7 +1376,7 @@ static int login_machine(int argc, char *argv[], void *userdata) {
         if (r < 0)
                 return log_error_errno(r, "Failed to attach bus to event loop: %m");
 
-        match = strappenda("type='signal',"
+        match = strjoina("type='signal',"
                            "sender='org.freedesktop.machine1',"
                            "path='/org/freedesktop/machine1',",
                            "interface='org.freedesktop.machine1.Manager',"
diff --git a/src/network/networkd-link.c b/src/network/networkd-link.c
index acdb486381..a8d9bc0a13 100644
--- a/src/network/networkd-link.c
+++ b/src/network/networkd-link.c
@@ -1243,7 +1243,7 @@ static int link_set_ipv4_forward(Link *link) {
 
         b = link_ipv4_forward_enabled(link);
 
-        p = strappenda("/proc/sys/net/ipv4/conf/", link->ifname, "/forwarding");
+        p = strjoina("/proc/sys/net/ipv4/conf/", link->ifname, "/forwarding");
         r = write_string_file_no_create(p, one_zero(b));
         if (r < 0)
                 log_link_warning_errno(link, r, "Cannot configure IPv4 forwarding for interface %s: %m", link->ifname);
@@ -1278,7 +1278,7 @@ static int link_set_ipv6_forward(Link *link) {
         const char *p = NULL;
         int r;
 
-        p = strappenda("/proc/sys/net/ipv6/conf/", link->ifname, "/forwarding");
+        p = strjoina("/proc/sys/net/ipv6/conf/", link->ifname, "/forwarding");
         r = write_string_file_no_create(p, one_zero(link_ipv6_forward_enabled(link)));
         if (r < 0)
                 log_link_warning_errno(link, r, "Cannot configure IPv6 forwarding for interface: %m");
diff --git a/src/nspawn/nspawn.c b/src/nspawn/nspawn.c
index 226c4415bb..1e6e7bf302 100644
--- a/src/nspawn/nspawn.c
+++ b/src/nspawn/nspawn.c
@@ -962,7 +962,7 @@ static int mount_cgroup_hierarchy(const char *dest, const char *controller, cons
         char *to;
         int r;
 
-        to = strappenda(dest, "/sys/fs/cgroup/", hierarchy);
+        to = strjoina(dest, "/sys/fs/cgroup/", hierarchy);
 
         r = path_is_mount_point(to, false);
         if (r < 0)
@@ -1004,7 +1004,7 @@ static int mount_cgroup(const char *dest) {
         if (r < 0)
                 return log_error_errno(r, "Failed to determine our own cgroup path: %m");
 
-        cgroup_root = strappenda(dest, "/sys/fs/cgroup");
+        cgroup_root = strjoina(dest, "/sys/fs/cgroup");
         if (mount("tmpfs", cgroup_root, "tmpfs", MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_STRICTATIME, "mode=755") < 0)
                 return log_error_errno(errno, "Failed to mount tmpfs to /sys/fs/cgroup: %m");
 
@@ -1057,12 +1057,12 @@ static int mount_cgroup(const char *dest) {
                 return r;
 
         /* Make our own cgroup a (writable) bind mount */
-        systemd_own = strappenda(dest, "/sys/fs/cgroup/systemd", own_cgroup_path);
+        systemd_own = strjoina(dest, "/sys/fs/cgroup/systemd", own_cgroup_path);
         if (mount(systemd_own, systemd_own,  NULL, MS_BIND, NULL) < 0)
                 return log_error_errno(errno, "Failed to turn %s into a bind mount: %m", own_cgroup_path);
 
         /* And then remount the systemd cgroup root read-only */
-        systemd_root = strappenda(dest, "/sys/fs/cgroup/systemd");
+        systemd_root = strjoina(dest, "/sys/fs/cgroup/systemd");
         if (mount(NULL, systemd_root, NULL, MS_BIND|MS_REMOUNT|MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_RDONLY, NULL) < 0)
                 return log_error_errno(errno, "Failed to mount cgroup root read-only: %m");
 
@@ -1215,7 +1215,7 @@ static int setup_volatile_state(const char *directory) {
         if (r < 0)
                 return log_error_errno(r, "Failed to remount %s read-only: %m", directory);
 
-        p = strappenda(directory, "/var");
+        p = strjoina(directory, "/var");
         r = mkdir(p, 0755);
         if (r < 0 && errno != EEXIST)
                 return log_error_errno(errno, "Failed to create %s: %m", directory);
@@ -1251,8 +1251,8 @@ static int setup_volatile(const char *directory) {
 
         tmpfs_mounted = true;
 
-        f = strappenda(directory, "/usr");
-        t = strappenda(template, "/usr");
+        f = strjoina(directory, "/usr");
+        t = strjoina(template, "/usr");
 
         r = mkdir(t, 0755);
         if (r < 0 && errno != EEXIST) {
@@ -1434,7 +1434,7 @@ static int setup_dev_console(const char *dest, const char *console) {
          * /dev/console. (Note that the major minor doesn't actually
          * matter here, since we mount it over anyway). */
 
-        to = strappenda(dest, "/dev/console");
+        to = strjoina(dest, "/dev/console");
         if (mknod(to, (st.st_mode & ~07777) | 0600, st.st_rdev) < 0)
                 return log_error_errno(errno, "mknod() for /dev/console failed: %m");
 
@@ -2564,10 +2564,10 @@ static int setup_propagate(const char *root) {
 
         (void) mkdir_p("/run/systemd/nspawn/", 0755);
         (void) mkdir_p("/run/systemd/nspawn/propagate", 0600);
-        p = strappenda("/run/systemd/nspawn/propagate/", arg_machine);
+        p = strjoina("/run/systemd/nspawn/propagate/", arg_machine);
         (void) mkdir_p(p, 0600);
 
-        q = strappenda(root, "/run/systemd/nspawn/incoming");
+        q = strjoina(root, "/run/systemd/nspawn/incoming");
         mkdir_parents(q, 0755);
         mkdir_p(q, 0600);
 
@@ -3050,7 +3050,7 @@ static int mount_device(const char *what, const char *where, const char *directo
                 rw = false;
 
         if (directory)
-                p = strappenda(where, directory);
+                p = strjoina(where, directory);
         else
                 p = where;
 
@@ -3685,7 +3685,7 @@ int main(int argc, char *argv[]) {
                 } else {
                         const char *p;
 
-                        p = strappenda(arg_directory,
+                        p = strjoina(arg_directory,
                                        argc > optind && path_is_absolute(argv[optind]) ? argv[optind] : "/usr/bin/");
                         if (access(p, F_OK) < 0) {
                                 log_error("Directory %s lacks the binary to execute or doesn't look like a binary tree. Refusing.", arg_directory);
@@ -4294,7 +4294,7 @@ finish:
         if (arg_machine) {
                 const char *p;
 
-                p = strappenda("/run/systemd/nspawn/propagate/", arg_machine);
+                p = strjoina("/run/systemd/nspawn/propagate/", arg_machine);
                 (void) rm_rf(p, false, true, false);
         }
 
diff --git a/src/resolve/resolved-bus.c b/src/resolve/resolved-bus.c
index 8161b5321f..03c84786db 100644
--- a/src/resolve/resolved-bus.c
+++ b/src/resolve/resolved-bus.c
@@ -76,7 +76,7 @@ static int reply_query_state(DnsQuery *q) {
                                 rc = p;
                         }
 
-                        n = strappenda(_BUS_ERROR_DNS, rc);
+                        n = strjoina(_BUS_ERROR_DNS, rc);
                         sd_bus_error_setf(&error, n, "Could not resolve '%s', server or network returned error %s", name, rc);
                 }
 
diff --git a/src/run/run.c b/src/run/run.c
index 723e0cb31a..0661b3bee9 100644
--- a/src/run/run.c
+++ b/src/run/run.c
@@ -494,7 +494,7 @@ static int transient_service_set_properties(sd_bus_message *m, char **argv, cons
                 if (e) {
                         char *n;
 
-                        n = strappenda("TERM=", e);
+                        n = strjoina("TERM=", e);
                         r = sd_bus_message_append(m,
                                                   "(sv)",
                                                   "Environment", "as", 1, n);
diff --git a/src/shared/cgroup-show.c b/src/shared/cgroup-show.c
index ea66c76724..cbd94e86d9 100644
--- a/src/shared/cgroup-show.c
+++ b/src/shared/cgroup-show.c
@@ -93,7 +93,7 @@ static int show_cgroup_one_by_path(const char *path, const char *prefix, unsigne
         if (r < 0)
                 return r;
 
-        fn = strappenda(p, "/cgroup.procs");
+        fn = strjoina(p, "/cgroup.procs");
         f = fopen(fn, "re");
         if (!f)
                 return -errno;
diff --git a/src/shared/cgroup-util.c b/src/shared/cgroup-util.c
index 0d3cc53517..b527868e6b 100644
--- a/src/shared/cgroup-util.c
+++ b/src/shared/cgroup-util.c
@@ -510,7 +510,7 @@ static int check_hierarchy(const char *p) {
                 return 0;
 
         /* Check if this controller actually really exists */
-        cc = strappenda("/sys/fs/cgroup/", p);
+        cc = strjoina("/sys/fs/cgroup/", p);
         if (laccess(cc, F_OK) < 0)
                 return -errno;
 
diff --git a/src/shared/condition.c b/src/shared/condition.c
index 4faca2b8dc..da7560f05f 100644
--- a/src/shared/condition.c
+++ b/src/shared/condition.c
@@ -288,7 +288,7 @@ static int condition_test_needs_update(Condition *c) {
         if (!path_is_absolute(c->parameter))
                 return true;
 
-        p = strappenda(c->parameter, "/.updated");
+        p = strjoina(c->parameter, "/.updated");
         if (lstat(p, &other) < 0)
                 return true;
 
diff --git a/src/shared/conf-files.c b/src/shared/conf-files.c
index 51f4e0105c..db4937db88 100644
--- a/src/shared/conf-files.c
+++ b/src/shared/conf-files.c
@@ -44,7 +44,7 @@ static int files_add(Hashmap *h, const char *root, const char *path, const char
         assert(path);
         assert(suffix);
 
-        dirpath = strappenda(root ? root : "", path);
+        dirpath = strjoina(root ? root : "", path);
 
         dir = opendir(dirpath);
         if (!dir) {
diff --git a/src/shared/generator.c b/src/shared/generator.c
index 4140afba82..7f16d5cbef 100644
--- a/src/shared/generator.c
+++ b/src/shared/generator.c
@@ -62,7 +62,7 @@ int generator_write_fsck_deps(
         if (streq(where, "/")) {
                 char *lnk;
 
-                lnk = strappenda(dest, "/" SPECIAL_LOCAL_FS_TARGET ".wants/systemd-fsck-root.service");
+                lnk = strjoina(dest, "/" SPECIAL_LOCAL_FS_TARGET ".wants/systemd-fsck-root.service");
 
                 mkdir_parents(lnk, 0755);
                 if (symlink(SYSTEM_DATA_UNIT_PATH "/systemd-fsck-root.service", lnk) < 0)
diff --git a/src/shared/install.c b/src/shared/install.c
index 37191a7c71..65f1c245c6 100644
--- a/src/shared/install.c
+++ b/src/shared/install.c
@@ -1048,7 +1048,7 @@ static int unit_file_load(
         assert(path);
 
         if (!isempty(root_dir))
-                path = strappenda(root_dir, "/", path);
+                path = strjoina(root_dir, "/", path);
 
         if (!load) {
                 r = access(path, F_OK) ? -errno : 0;
@@ -1730,7 +1730,7 @@ int unit_file_set_default(
         if (r < 0)
                 return r;
 
-        path = strappenda(config_path, "/" SPECIAL_DEFAULT_TARGET);
+        path = strjoina(config_path, "/" SPECIAL_DEFAULT_TARGET);
 
         r = create_symlink(i->path, path, force, changes, n_changes);
         if (r < 0)
diff --git a/src/shared/logs-show.c b/src/shared/logs-show.c
index b7a99d2c23..45741f9e9d 100644
--- a/src/shared/logs-show.c
+++ b/src/shared/logs-show.c
@@ -1033,10 +1033,10 @@ int add_matches_for_unit(sd_journal *j, const char *unit) {
         assert(j);
         assert(unit);
 
-        m1 = strappenda("_SYSTEMD_UNIT=", unit);
-        m2 = strappenda("COREDUMP_UNIT=", unit);
-        m3 = strappenda("UNIT=", unit);
-        m4 = strappenda("OBJECT_SYSTEMD_UNIT=", unit);
+        m1 = strjoina("_SYSTEMD_UNIT=", unit);
+        m2 = strjoina("COREDUMP_UNIT=", unit);
+        m3 = strjoina("UNIT=", unit);
+        m4 = strjoina("OBJECT_SYSTEMD_UNIT=", unit);
 
         (void)(
             /* Look for messages from the service itself */
@@ -1080,10 +1080,10 @@ int add_matches_for_user_unit(sd_journal *j, const char *unit, uid_t uid) {
         assert(j);
         assert(unit);
 
-        m1 = strappenda("_SYSTEMD_USER_UNIT=", unit);
-        m2 = strappenda("USER_UNIT=", unit);
-        m3 = strappenda("COREDUMP_USER_UNIT=", unit);
-        m4 = strappenda("OBJECT_SYSTEMD_USER_UNIT=", unit);
+        m1 = strjoina("_SYSTEMD_USER_UNIT=", unit);
+        m2 = strjoina("USER_UNIT=", unit);
+        m3 = strjoina("COREDUMP_USER_UNIT=", unit);
+        m4 = strjoina("OBJECT_SYSTEMD_USER_UNIT=", unit);
         sprintf(muid, "_UID="UID_FMT, uid);
 
         (void) (
diff --git a/src/shared/machine-image.c b/src/shared/machine-image.c
index 8ea61052bd..8d61507e84 100644
--- a/src/shared/machine-image.c
+++ b/src/shared/machine-image.c
@@ -425,7 +425,7 @@ int image_rename(Image *i, const char *new_name) {
         case IMAGE_RAW: {
                 const char *fn;
 
-                fn = strappenda(new_name, ".raw");
+                fn = strjoina(new_name, ".raw");
                 new_path = file_in_same_dir(i->path, fn);
                 break;
         }
@@ -486,13 +486,13 @@ int image_clone(Image *i, const char *new_name, bool read_only) {
 
         case IMAGE_SUBVOLUME:
         case IMAGE_DIRECTORY:
-                new_path = strappenda("/var/lib/machines/", new_name);
+                new_path = strjoina("/var/lib/machines/", new_name);
 
                 r = btrfs_subvol_snapshot(i->path, new_path, read_only, true);
                 break;
 
         case IMAGE_RAW:
-                new_path = strappenda("/var/lib/machines/", new_name, ".raw");
+                new_path = strjoina("/var/lib/machines/", new_name, ".raw");
 
                 r = copy_file_atomic(i->path, new_path, read_only ? 0444 : 0644, false, FS_NOCOW_FL);
                 break;
@@ -629,7 +629,7 @@ int image_name_lock(const char *name, int operation, LockFile *ret) {
                 return -EBUSY;
 
         mkdir_p("/run/systemd/nspawn/locks", 0600);
-        p = strappenda("/run/systemd/nspawn/locks/name-", name);
+        p = strjoina("/run/systemd/nspawn/locks/name-", name);
 
         return make_lock_file(p, operation, ret);
 }
diff --git a/src/shared/pager.c b/src/shared/pager.c
index a9f2b7e4f4..8635d9a600 100644
--- a/src/shared/pager.c
+++ b/src/shared/pager.c
@@ -91,7 +91,7 @@ int pager_open(bool jump_to_end) {
                 if (!less_opts)
                         less_opts = "FRSXMK";
                 if (jump_to_end)
-                        less_opts = strappenda(less_opts, " +G");
+                        less_opts = strjoina(less_opts, " +G");
                 setenv("LESS", less_opts, 1);
 
                 /* Make sure the pager goes away when the parent dies */
diff --git a/src/shared/path-util.c b/src/shared/path-util.c
index 00d2d44993..b9db7f1047 100644
--- a/src/shared/path-util.c
+++ b/src/shared/path-util.c
@@ -560,14 +560,14 @@ int path_is_os_tree(const char *path) {
         int r;
 
         /* We use /usr/lib/os-release as flag file if something is an OS */
-        p = strappenda(path, "/usr/lib/os-release");
+        p = strjoina(path, "/usr/lib/os-release");
         r = access(p, F_OK);
 
         if (r >= 0)
                 return 1;
 
         /* Also check for the old location in /etc, just in case. */
-        p = strappenda(path, "/etc/os-release");
+        p = strjoina(path, "/etc/os-release");
         r = access(p, F_OK);
 
         return r >= 0;
@@ -665,7 +665,7 @@ int fsck_exists(const char *fstype) {
         const char *checker;
         int r;
 
-        checker = strappenda("fsck.", fstype);
+        checker = strjoina("fsck.", fstype);
 
         r = find_binary(checker, true, &p);
         if (r < 0)
diff --git a/src/shared/switch-root.c b/src/shared/switch-root.c
index e8cedc69cc..813641ad44 100644
--- a/src/shared/switch-root.c
+++ b/src/shared/switch-root.c
@@ -51,7 +51,7 @@ int switch_root(const char *new_root, const char *oldroot, bool detach_oldroot,
         if (path_equal(new_root, "/"))
                 return 0;
 
-        temporary_old_root = strappenda(new_root, oldroot);
+        temporary_old_root = strjoina(new_root, oldroot);
         mkdir_p_label(temporary_old_root, 0755);
 
         old_root_remove = in_initrd();
diff --git a/src/shared/time-util.c b/src/shared/time-util.c
index d3404afd55..947ac1fcfb 100644
--- a/src/shared/time-util.c
+++ b/src/shared/time-util.c
@@ -965,7 +965,7 @@ bool timezone_is_valid(const char *name) {
         if (slash)
                 return false;
 
-        t = strappenda("/usr/share/zoneinfo/", name);
+        t = strjoina("/usr/share/zoneinfo/", name);
         if (stat(t, &st) < 0)
                 return false;
 
diff --git a/src/shared/util.c b/src/shared/util.c
index 11cab6dcf1..c53f9cdb6a 100644
--- a/src/shared/util.c
+++ b/src/shared/util.c
@@ -6452,7 +6452,7 @@ int container_get_leader(const char *machine, pid_t *pid) {
         assert(machine);
         assert(pid);
 
-        p = strappenda("/run/systemd/machines/", machine);
+        p = strjoina("/run/systemd/machines/", machine);
         r = parse_env_file(p, NEWLINE, "LEADER", &s, "CLASS", &class, NULL);
         if (r == -ENOENT)
                 return -EHOSTDOWN;
@@ -6691,7 +6691,7 @@ int open_tmpfile(const char *path, int flags) {
 #endif
 
         /* Fall back to unguessable name + unlinking */
-        p = strappenda(path, "/systemd-tmp-XXXXXX");
+        p = strjoina(path, "/systemd-tmp-XXXXXX");
 
         fd = mkostemp_safe(p, flags);
         if (fd < 0)
@@ -7220,7 +7220,7 @@ int take_password_lock(const char *root) {
          * awfully racy, and thus we just won't do them. */
 
         if (root)
-                path = strappenda(root, "/etc/.pwd.lock");
+                path = strjoina(root, "/etc/.pwd.lock");
         else
                 path = "/etc/.pwd.lock";
 
diff --git a/src/shared/util.h b/src/shared/util.h
index 410ce65f14..7dfabbc07d 100644
--- a/src/shared/util.h
+++ b/src/shared/util.h
@@ -931,19 +931,19 @@ int unlink_noerrno(const char *path);
                 (void*)memset(_new_, 0, _size_);                        \
         })
 
-#define strappenda(a, ...)                                       \
-        ({                                                       \
-                int _len = strlen(a);                            \
-                unsigned _i;                                     \
-                char *_d_, *_p_;                                 \
-                const char *_appendees_[] = { __VA_ARGS__ };     \
-                for (_i = 0; _i < ELEMENTSOF(_appendees_); _i++) \
-                        _len += strlen(_appendees_[_i]);         \
-                _d_ = alloca(_len + 1);                          \
-                _p_ = stpcpy(_d_, a);                            \
-                for (_i = 0; _i < ELEMENTSOF(_appendees_); _i++) \
-                        _p_ = stpcpy(_p_, _appendees_[_i]);      \
-                _d_;                                             \
+#define strjoina(a, ...)                                                \
+        ({                                                              \
+                const char *_appendees_[] = { a, __VA_ARGS__ };         \
+                char *_d_, *_p_;                                        \
+                int _len_ = 0;                                          \
+                unsigned _i_;                                           \
+                for (_i_ = 0; _i_ < ELEMENTSOF(_appendees_) && _appendees_[_i_]; _i_++) \
+                        _len_ += strlen(_appendees_[_i_]);              \
+                _p_ = _d_ = alloca(_len_ + 1);                          \
+                for (_i_ = 0; _i_ < ELEMENTSOF(_appendees_) && _appendees_[_i_]; _i_++) \
+                        _p_ = stpcpy(_p_, _appendees_[_i_]);            \
+                *_p_ = 0;                                               \
+                _d_;                                                    \
         })
 
 #define procfs_file_alloca(pid, field)                                  \
diff --git a/src/system-update-generator/system-update-generator.c b/src/system-update-generator/system-update-generator.c
index 455a84109b..ad34ef1366 100644
--- a/src/system-update-generator/system-update-generator.c
+++ b/src/system-update-generator/system-update-generator.c
@@ -45,7 +45,7 @@ static int generate_symlink(void) {
                 return -EINVAL;
         }
 
-        p = strappenda(arg_dest, "/default.target");
+        p = strjoina(arg_dest, "/default.target");
         if (symlink(SYSTEM_DATA_UNIT_PATH "/system-update.target", p) < 0)
                 return log_error_errno(errno, "Failed to create symlink %s: %m", p);
 
diff --git a/src/systemctl/systemctl.c b/src/systemctl/systemctl.c
index 11b0be001f..462f7fdc33 100644
--- a/src/systemctl/systemctl.c
+++ b/src/systemctl/systemctl.c
@@ -4978,8 +4978,8 @@ static int switch_root(sd_bus *bus, char **args) {
         if (init) {
                 const char *root_systemd_path = NULL, *root_init_path = NULL;
 
-                root_systemd_path = strappenda(root, "/" SYSTEMD_BINARY_PATH);
-                root_init_path = strappenda(root, "/", init);
+                root_systemd_path = strjoina(root, "/" SYSTEMD_BINARY_PATH);
+                root_init_path = strjoina(root, "/", init);
 
                 /* If the passed init is actually the same as the
                  * systemd binary, then let's suppress it. */
@@ -5783,7 +5783,7 @@ static int unit_file_create_dropin(const char *unit_name, const char *user_home,
         assert(ret_new_path);
         assert(ret_tmp_path);
 
-        ending = strappenda(unit_name, ".d/override.conf");
+        ending = strjoina(unit_name, ".d/override.conf");
         r = get_file_to_edit(ending, user_home, user_runtime, &tmp_new_path);
         if (r < 0)
                 return r;
diff --git a/src/sysusers/sysusers.c b/src/sysusers/sysusers.c
index f25ece0674..e47bcb4dca 100644
--- a/src/sysusers/sysusers.c
+++ b/src/sysusers/sysusers.c
@@ -81,7 +81,7 @@ static uid_t search_uid = UID_INVALID;
 static UidRange *uid_range = NULL;
 static unsigned n_uid_range = 0;
 
-#define fix_root(x) (arg_root ? strappenda(arg_root, x) : x)
+#define fix_root(x) (arg_root ? strjoina(arg_root, x) : x)
 
 static int load_user_database(void) {
         _cleanup_fclose_ FILE *f = NULL;
@@ -217,7 +217,7 @@ static int make_backup(const char *target, const char *x) {
         /* Don't fail on chmod() or chown(). If it stays owned by us
          * and/or unreadable by others, then it isn't too bad... */
 
-        backup = strappenda(x, "-");
+        backup = strjoina(x, "-");
 
         /* Copy over the access mask */
         if (fchmod(fileno(dst), st.st_mode & 07777) < 0)
diff --git a/src/test/test-conf-files.c b/src/test/test-conf-files.c
index 71cfc022dd..894c7f742f 100644
--- a/src/test/test-conf-files.c
+++ b/src/test/test-conf-files.c
@@ -59,12 +59,12 @@ static void test_conf_files_list(bool use_root) {
                 search_2 = "/dir2";
         } else {
                 root_dir = NULL;
-                search_1 = strappenda(tmp_dir, "/dir1");
-                search_2 = strappenda(tmp_dir, "/dir2");
+                search_1 = strjoina(tmp_dir, "/dir1");
+                search_2 = strjoina(tmp_dir, "/dir2");
         }
 
-        expect_a = strappenda(tmp_dir, "/dir1/a.conf");
-        expect_b = strappenda(tmp_dir, "/dir2/b.conf");
+        expect_a = strjoina(tmp_dir, "/dir1/a.conf");
+        expect_b = strjoina(tmp_dir, "/dir2/b.conf");
 
         assert_se(conf_files_list(&found_files, ".conf", root_dir, search_1, search_2, NULL) == 0);
         strv_print(found_files);
diff --git a/src/test/test-copy.c b/src/test/test-copy.c
index 3e1607e51d..5c96f61005 100644
--- a/src/test/test-copy.c
+++ b/src/test/test-copy.c
@@ -90,15 +90,15 @@ static void test_copy_tree(void) {
         rm_rf_dangerous(original_dir, false, true, false);
 
         STRV_FOREACH(p, files) {
-                char *f = strappenda(original_dir, *p);
+                char *f = strjoina(original_dir, *p);
 
                 assert_se(mkdir_parents(f, 0755) >= 0);
                 assert_se(write_string_file(f, "file") == 0);
         }
 
         STRV_FOREACH_PAIR(link, p, links) {
-                char *f = strappenda(original_dir, *p);
-                char *l = strappenda(original_dir, *link);
+                char *f = strjoina(original_dir, *p);
+                char *l = strjoina(original_dir, *link);
 
                 assert_se(mkdir_parents(l, 0755) >= 0);
                 assert_se(symlink(f, l) == 0);
@@ -109,7 +109,7 @@ static void test_copy_tree(void) {
         STRV_FOREACH(p, files) {
                 _cleanup_free_ char *buf = NULL;
                 size_t sz = 0;
-                char *f = strappenda(copy_dir, *p);
+                char *f = strjoina(copy_dir, *p);
 
                 assert_se(access(f, F_OK) == 0);
                 assert_se(read_full_file(f, &buf, &sz) == 0);
@@ -118,8 +118,8 @@ static void test_copy_tree(void) {
 
         STRV_FOREACH_PAIR(link, p, links) {
                 _cleanup_free_ char *target = NULL;
-                char *f = strappenda(original_dir, *p);
-                char *l = strappenda(copy_dir, *link);
+                char *f = strjoina(original_dir, *p);
+                char *l = strjoina(copy_dir, *link);
 
                 assert_se(readlink_and_canonicalize(l, &target) == 0);
                 assert_se(path_equal(f, target));
diff --git a/src/test/test-namespace.c b/src/test/test-namespace.c
index 084a58f3aa..2397db5fff 100644
--- a/src/test/test-namespace.c
+++ b/src/test/test-namespace.c
@@ -42,8 +42,8 @@ static void test_tmpdir(const char *id, const char *A, const char *B) {
         assert_se((x.st_mode & 01777) == 0700);
         assert_se((y.st_mode & 01777) == 0700);
 
-        c = strappenda(a, "/tmp");
-        d = strappenda(b, "/tmp");
+        c = strjoina(a, "/tmp");
+        d = strjoina(b, "/tmp");
 
         assert_se(stat(c, &x) >= 0);
         assert_se(stat(d, &y) >= 0);
diff --git a/src/test/test-path-lookup.c b/src/test/test-path-lookup.c
index a6ce8c9d8d..38e5c93df6 100644
--- a/src/test/test-path-lookup.c
+++ b/src/test/test-path-lookup.c
@@ -33,9 +33,9 @@ static void test_paths(SystemdRunningAs running_as, bool personal) {
         char *exists, *not;
 
         assert_se(mkdtemp(template));
-        exists = strappenda(template, "/exists");
+        exists = strjoina(template, "/exists");
         assert_se(mkdir(exists, 0755) == 0);
-        not = strappenda(template, "/not");
+        not = strjoina(template, "/not");
 
         assert_se(lookup_paths_init(&lp, running_as, personal, NULL, exists, not, not) == 0);
 
diff --git a/src/test/test-path.c b/src/test/test-path.c
index 1512ae2b19..4f9f5c1344 100644
--- a/src/test/test-path.c
+++ b/src/test/test-path.c
@@ -47,7 +47,7 @@ static int setup_test(Manager **m) {
         assert_se(manager_startup(tmp, NULL, NULL) >= 0);
 
         STRV_FOREACH(test_path, tests_path) {
-               rm_rf_dangerous(strappenda("/tmp/test-path_", *test_path), false, true, false);
+               rm_rf_dangerous(strjoina("/tmp/test-path_", *test_path), false, true, false);
         }
 
         *m = tmp;
@@ -201,7 +201,7 @@ static void test_path_directorynotempty(Manager *m) {
         assert_se(access(test_path, F_OK) < 0);
 
         assert_se(mkdir_p(test_path, 0755) >= 0);
-        assert_se(touch(strappenda(test_path, "test_file")) >= 0);
+        assert_se(touch(strjoina(test_path, "test_file")) >= 0);
 
         check_stop_unlink(m, unit, test_path, NULL);
 }
diff --git a/src/test/test-tmpfiles.c b/src/test/test-tmpfiles.c
index 84050c6fa4..4b72c4a8fa 100644
--- a/src/test/test-tmpfiles.c
+++ b/src/test/test-tmpfiles.c
@@ -30,7 +30,7 @@
 
 int main(int argc, char** argv) {
         const char *p = argv[1] ?: "/tmp";
-        char *pattern = strappenda(p, "/systemd-test-XXXXXX");
+        char *pattern = strjoina(p, "/systemd-test-XXXXXX");
         _cleanup_close_ int fd, fd2;
         _cleanup_free_ char *cmd, *cmd2;
 
diff --git a/src/test/test-util.c b/src/test/test-util.c
index f2b7038a4d..804f522e92 100644
--- a/src/test/test-util.c
+++ b/src/test/test-util.c
@@ -1072,17 +1072,29 @@ static void test_strshorten(void) {
         assert_se(strlen(strshorten(s, 0)) == 0);
 }
 
-static void test_strappenda(void) {
+static void test_strjoina(void) {
         char *actual;
 
-        actual = strappenda("", "foo", "bar");
+        actual = strjoina("", "foo", "bar");
         assert_se(streq(actual, "foobar"));
 
-        actual = strappenda("foo", "bar", "baz");
+        actual = strjoina("foo", "bar", "baz");
         assert_se(streq(actual, "foobarbaz"));
 
-        actual = strappenda("foo", "", "bar", "baz");
+        actual = strjoina("foo", "", "bar", "baz");
         assert_se(streq(actual, "foobarbaz"));
+
+        actual = strjoina("foo");
+        assert_se(streq(actual, "foo"));
+
+        actual = strjoina(NULL);
+        assert_se(streq(actual, ""));
+
+        actual = strjoina(NULL, "foo");
+        assert_se(streq(actual, ""));
+
+        actual = strjoina("foo", NULL, "bar");
+        assert_se(streq(actual, "foo"));
 }
 
 static void test_is_symlink(void) {
@@ -1231,13 +1243,13 @@ static void test_execute_directory(void) {
         assert_se(mkdtemp(template_lo));
         assert_se(mkdtemp(template_hi));
 
-        name = strappenda(template_lo, "/script");
-        name2 = strappenda(template_hi, "/script2");
-        name3 = strappenda(template_lo, "/useless");
-        overridden = strappenda(template_lo, "/overridden");
-        override = strappenda(template_hi, "/overridden");
-        masked = strappenda(template_lo, "/masked");
-        mask = strappenda(template_hi, "/masked");
+        name = strjoina(template_lo, "/script");
+        name2 = strjoina(template_hi, "/script2");
+        name3 = strjoina(template_lo, "/useless");
+        overridden = strjoina(template_lo, "/overridden");
+        override = strjoina(template_hi, "/overridden");
+        masked = strjoina(template_lo, "/masked");
+        mask = strjoina(template_hi, "/masked");
 
         assert_se(write_string_file(name, "#!/bin/sh\necho 'Executing '$0\ntouch $(dirname $0)/it_works") == 0);
         assert_se(write_string_file(name2, "#!/bin/sh\necho 'Executing '$0\ntouch $(dirname $0)/it_works2") == 0);
@@ -1562,7 +1574,7 @@ int main(int argc, char *argv[]) {
         test_read_one_char();
         test_ignore_signals();
         test_strshorten();
-        test_strappenda();
+        test_strjoina();
         test_is_symlink();
         test_pid_is_unwaited();
         test_pid_is_alive();
diff --git a/src/tty-ask-password-agent/tty-ask-password-agent.c b/src/tty-ask-password-agent/tty-ask-password-agent.c
index b4405ce8f1..bdf651246b 100644
--- a/src/tty-ask-password-agent/tty-ask-password-agent.c
+++ b/src/tty-ask-password-agent/tty-ask-password-agent.c
@@ -385,7 +385,7 @@ static bool wall_tty_match(const char *path) {
         _cleanup_free_ char *p = NULL;
 
         if (!path_is_absolute(path))
-                path = strappenda("/dev/", path);
+                path = strjoina("/dev/", path);
 
         r = lstat(path, &st);
         if (r < 0)
diff --git a/src/udev/udev-builtin-net_id.c b/src/udev/udev-builtin-net_id.c
index c310111eb9..37ff1b8008 100644
--- a/src/udev/udev-builtin-net_id.c
+++ b/src/udev/udev-builtin-net_id.c
@@ -153,7 +153,7 @@ static bool is_pci_multifunction(struct udev_device *dev) {
         const char *filename;
         uint8_t config[64];
 
-        filename = strappenda(udev_device_get_syspath(dev), "/config");
+        filename = strjoina(udev_device_get_syspath(dev), "/config");
         f = fopen(filename, "re");
         if (!f)
                 return false;
diff --git a/src/udev/udevadm-util.c b/src/udev/udevadm-util.c
index 37e80c31df..3f0e45e26c 100644
--- a/src/udev/udevadm-util.c
+++ b/src/udev/udevadm-util.c
@@ -25,7 +25,7 @@ struct udev_device *find_device(struct udev *udev,
         assert(id);
 
         if (prefix && !startswith(id, prefix))
-                id = strappenda(prefix, id);
+                id = strjoina(prefix, id);
 
         if (startswith(id, "/dev/")) {
                 struct stat statbuf;