various: use strdup_to() in various obvious cases

strdup_to() returns 0 on success and here we convert obvious blocks
which either return -ENOMEM or 0.

src/basic/chase.c

@@ -741,12 +741,7 @@ int chase_extract_filename(const char *path, const char *root, char **ret) {
                         return r;
         }
 
-        char *fname = strdup(".");
-        if (!fname)
-                return -ENOMEM;
-
-        *ret = fname;
-        return 0;
+        return strdup_to(ret, ".");
 }
 
 int chase_and_open(const char *path, const char *root, ChaseFlags chase_flags, int open_flags, char **ret_path) {

src/basic/devnum-util.c

@@ -58,21 +58,18 @@ int device_path_make_major_minor(mode_t mode, dev_t devnum, char **ret) {
 }
 
 int device_path_make_inaccessible(mode_t mode, char **ret) {
-        char *s;
+        const char *s;
 
         assert(ret);
 
         if (S_ISCHR(mode))
-                s = strdup("/run/systemd/inaccessible/chr");
+                s = "/run/systemd/inaccessible/chr";
         else if (S_ISBLK(mode))
-                s = strdup("/run/systemd/inaccessible/blk");
+                s = "/run/systemd/inaccessible/blk";
         else
                 return -ENODEV;
-        if (!s)
-                return -ENOMEM;
 
-        *ret = s;
-        return 0;
+        return strdup_to(ret, s);
 }
 
 int device_path_make_canonical(mode_t mode, dev_t devnum, char **ret) {

src/basic/format-util.c

@@ -25,7 +25,7 @@ int format_ifname_full(int ifindex, FormatIfnameFlag flag, char buf[static IF_NA
 }
 
 int format_ifname_full_alloc(int ifindex, FormatIfnameFlag flag, char **ret) {
-        char buf[IF_NAMESIZE], *copy;
+        char buf[IF_NAMESIZE];
         int r;
 
         assert(ret);
@@ -34,12 +34,7 @@ int format_ifname_full_alloc(int ifindex, FormatIfnameFlag flag, char **ret) {
         if (r < 0)
                 return r;
 
-        copy = strdup(buf);
-        if (!copy)
-                return -ENOMEM;
-
-        *ret = copy;
-        return 0;
+        return strdup_to(ret, buf);
 }
 
 char *format_bytes_full(char *buf, size_t l, uint64_t t, FormatBytesFlag flag) {

src/basic/path-util.c

@@ -1094,7 +1094,6 @@ int path_extract_filename(const char *path, char **ret) {
 }
 
 int path_extract_directory(const char *path, char **ret) {
-        _cleanup_free_ char *a = NULL;
         const char *c, *next = NULL;
         int r;
 
@@ -1118,14 +1117,10 @@ int path_extract_directory(const char *path, char **ret) {
                 if (*path != '/') /* filename only */
                         return -EDESTADDRREQ;
 
-                a = strdup("/");
-                if (!a)
-                        return -ENOMEM;
-                *ret = TAKE_PTR(a);
-                return 0;
+                return strdup_to(ret, "/");
         }
 
-        a = strndup(path, next - path);
+        _cleanup_free_ char *a = strndup(path, next - path);
         if (!a)
                 return -ENOMEM;
 

src/basic/terminal-util.c

@@ -697,18 +697,10 @@ int vtnr_from_tty(const char *tty) {
                 tty = active;
         }
 
-        if (tty == active)
-                *ret = TAKE_PTR(active);
-        else {
-                char *tmp;
-
-                tmp = strdup(tty);
-                if (!tmp)
-                        return -ENOMEM;
-
-                *ret = tmp;
-        }
+        if (tty != active)
+                return strdup_to(ret, tty);
 
+        *ret = TAKE_PTR(active);
         return 0;
 }
 
@@ -988,7 +980,7 @@ bool on_tty(void) {
 }
 
 int getttyname_malloc(int fd, char **ret) {
-        char path[PATH_MAX], *c; /* PATH_MAX is counted *with* the trailing NUL byte */
+        char path[PATH_MAX]; /* PATH_MAX is counted *with* the trailing NUL byte */
         int r;
 
         assert(fd >= 0);
@@ -1001,12 +993,7 @@ int getttyname_malloc(int fd, char **ret) {
         if (r > 0)
                 return -r;
 
-        c = strdup(skip_dev_prefix(path));
-        if (!c)
-                return -ENOMEM;
-
-        *ret = c;
-        return 0;
+        return strdup_to(ret, skip_dev_prefix(path));
 }
 
 int getttyname_harder(int fd, char **ret) {

src/basic/unit-name.c

@@ -793,12 +793,7 @@ int unit_name_mangle_with_suffix(
         return 1;
 
 good:
-        s = strdup(name);
-        if (!s)
-                return -ENOMEM;
-
-        *ret = TAKE_PTR(s);
-        return 0;
+        return strdup_to(ret, name);
 }
 
 int slice_build_parent_slice(const char *slice, char **ret) {

src/home/homed-home.c

@@ -3145,7 +3145,6 @@ int home_schedule_operation(Home *h, Operation *o, sd_bus_error *error) {
 
 static int home_get_image_path_seat(Home *h, char **ret) {
         _cleanup_(sd_device_unrefp) sd_device *d = NULL;
-        _cleanup_free_ char *c = NULL;
         const char *ip, *seat;
         struct stat st;
         int r;
@@ -3178,12 +3177,7 @@ static int home_get_image_path_seat(Home *h, char **ret) {
         else if (r < 0)
                 return r;
 
-        c = strdup(seat);
-        if (!c)
-                return -ENOMEM;
-
-        *ret = TAKE_PTR(c);
-        return 0;
+        return strdup_to(ret, seat);
 }
 
 int home_auto_login(Home *h, char ***ret_seats) {

src/locale/localed.c

@@ -158,11 +158,7 @@ static int process_locale_list_item(
                 if (new_locale[p])
                         return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Locale variable %s set twice, refusing.", name);
 
-                new_locale[p] = strdup(e);
-                if (!new_locale[p])
-                        return -ENOMEM;
-
-                return 0;
+                return strdup_to(&new_locale[p], e);
         }
 
         return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Locale assignment %s not valid, refusing.", assignment);

src/login/loginctl.c

@@ -1028,7 +1028,6 @@ static int get_bus_path_by_id(
 
         _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
         _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
-        _cleanup_free_ char *p = NULL;
         const char *path;
         int r;
 
@@ -1047,12 +1046,7 @@ static int get_bus_path_by_id(
         if (r < 0)
                 return bus_log_parse_error(r);
 
-        p = strdup(path);
-        if (!p)
-                return log_oom();
-
-        *ret = TAKE_PTR(p);
-        return 0;
+        return strdup_to(ret, path);
 }
 
 static int show_session(int argc, char *argv[], void *userdata) {

src/login/logind-session-device.c

@@ -314,11 +314,7 @@ static int session_device_verify(SessionDevice *sd) {
         if (sd->device->seat != sd->session->seat)
                 return -EPERM;
 
-        sd->node = strdup(node);
-        if (!sd->node)
-                return -ENOMEM;
-
-        return 0;
+        return strdup_to(&sd->node, node);
 }
 
 int session_device_new(Session *s, dev_t dev, bool open_device, SessionDevice **ret) {

src/resolve/resolved-dnssd.c

@@ -140,16 +140,10 @@ static int dnssd_service_load(Manager *manager, const char *filename) {
 
 static int specifier_dnssd_hostname(char specifier, const void *data, const char *root, const void *userdata, char **ret) {
         const Manager *m = ASSERT_PTR(userdata);
-        char *n;
 
         assert(m->llmnr_hostname);
 
-        n = strdup(m->llmnr_hostname);
-        if (!n)
-                return -ENOMEM;
-
-        *ret = n;
-        return 0;
+        return strdup_to(ret, m->llmnr_hostname);
 }
 
 int dnssd_render_instance_name(Manager *m, DnssdService *s, char **ret) {

src/shared/ethtool-util.c

@@ -182,7 +182,6 @@ int ethtool_get_driver(int *ethtool_fd, const char *ifname, char **ret) {
         struct ifreq ifr = {
                 .ifr_data = (void*) &ecmd,
         };
-        char *d;
         int r;
 
         assert(ethtool_fd);
@@ -201,12 +200,7 @@ int ethtool_get_driver(int *ethtool_fd, const char *ifname, char **ret) {
         if (isempty(ecmd.driver))
                 return -ENODATA;
 
-        d = strdup(ecmd.driver);
-        if (!d)
-                return -ENOMEM;
-
-        *ret = d;
-        return 0;
+        return strdup_to(ret, ecmd.driver);
 }
 
 int ethtool_get_link_info(

src/shared/install.c

@@ -3042,17 +3042,16 @@ int unit_file_set_default(
 int unit_file_get_default(
                 RuntimeScope scope,
                 const char *root_dir,
-                char **name) {
+                char **ret) {
 
         _cleanup_(lookup_paths_done) LookupPaths lp = {};
         _cleanup_(install_context_done) InstallContext ctx = { .scope = scope };
         InstallInfo *info;
-        char *n;
         int r;
 
         assert(scope >= 0);
         assert(scope < _RUNTIME_SCOPE_MAX);
-        assert(name);
+        assert(ret);
 
         r = lookup_paths_init(&lp, scope, 0, root_dir);
         if (r < 0)
@@ -3063,12 +3062,7 @@ int unit_file_get_default(
         if (r < 0)
                 return r;
 
-        n = strdup(info->name);
-        if (!n)
-                return -ENOMEM;
-
-        *name = n;
-        return 0;
+        return strdup_to(ret, info->name);
 }
 
 int unit_file_lookup_state(

src/shared/install.h

@@ -175,7 +175,7 @@ int unit_file_set_default(
 int unit_file_get_default(
                 RuntimeScope scope,
                 const char *root_dir,
-                char **name);
+                char **ret);
 int unit_file_add_dependency(
                 RuntimeScope scope,
                 UnitFileFlags flags,

src/shared/libcrypt-util.c

@@ -140,7 +140,7 @@ static char* systemd_crypt_ra(const char *phrase, const char *setting, void **da
 int hash_password_full(const char *password, void **cd_data, int *cd_size, char **ret) {
         _cleanup_free_ char *salt = NULL;
         _cleanup_(erase_and_freep) void *_cd_data = NULL;
-        char *p;
+        const char *p;
         int r, _cd_size = 0;
 
         assert(!!cd_data == !!cd_size);
@@ -155,12 +155,7 @@ int hash_password_full(const char *password, void **cd_data, int *cd_size, char
                 return log_debug_errno(errno_or_else(SYNTHETIC_ERRNO(EINVAL)),
                                        CRYPT_RA_NAME "() failed: %m");
 
-        p = strdup(p);
-        if (!p)
-                return -ENOMEM;
-
-        *ret = p;
-        return 0;
+        return strdup_to(ret, p);
 }
 
 bool looks_like_hashed_password(const char *s) {

src/shared/netif-util.c

@@ -32,14 +32,8 @@ int net_get_type_string(sd_device *device, uint16_t iftype, char **ret) {
 
         if (device &&
             sd_device_get_devtype(device, &t) >= 0 &&
-            !isempty(t)) {
-                p = strdup(t);
-                if (!p)
-                        return -ENOMEM;
-
-                *ret = p;
-                return 0;
-        }
+            !isempty(t))
+                return strdup_to(ret, t);
 
         t = arphrd_to_name(iftype);
         if (!t)

src/shared/pretty-print.c

@@ -141,16 +141,8 @@ int terminal_urlify_path(const char *path, const char *text, char **ret) {
         if (isempty(text))
                 text = path;
 
-        if (!urlify_enabled()) {
-                char *n;
-
-                n = strdup(text);
-                if (!n)
-                        return -ENOMEM;
-
-                *ret = n;
-                return 0;
-        }
+        if (!urlify_enabled())
+                return strdup_to(ret, text);
 
         r = file_url_from_path(path, &url);
         if (r < 0)