diff --git a/src/basic/cgroup-util.c b/src/basic/cgroup-util.c
index 9b145aa70f..446f63023b 100644
--- a/src/basic/cgroup-util.c
+++ b/src/basic/cgroup-util.c
@@ -81,7 +81,7 @@ int cg_read_pid(FILE *f, pid_t *_pid) {
                 if (feof(f))
                         return 0;
 
-                return errno > 0 ? -errno : -EIO;
+                return errno_or_else(EIO);
         }
 
         if (ul <= 0)
@@ -770,10 +770,8 @@ int cg_trim(const char *controller, const char *path, bool delete_root) {
         if (nftw(fs, trim_cb, 64, FTW_DEPTH|FTW_MOUNT|FTW_PHYS) != 0) {
                 if (errno == ENOENT)
                         r = 0;
-                else if (errno > 0)
-                        r = -errno;
                 else
-                        r = -EIO;
+                        r = errno_or_else(EIO);
         }
 
         if (delete_root) {
@@ -2502,8 +2500,8 @@ int cg_kernel_controllers(Set **ret) {
                         if (feof(f))
                                 break;
 
-                        if (ferror(f) && errno > 0)
-                                return -errno;
+                        if (ferror(f))
+                                return errno_or_else(EIO);
 
                         return -EBADMSG;
                 }
diff --git a/src/basic/fileio.c b/src/basic/fileio.c
index 40a20c2b3b..bd4c964bec 100644
--- a/src/basic/fileio.c
+++ b/src/basic/fileio.c
@@ -298,7 +298,7 @@ int verify_file(const char *fn, const char *blob, bool accept_extra_nl) {
         errno = 0;
         k = fread(buf, 1, l + accept_extra_nl + 1, f);
         if (ferror(f))
-                return errno > 0 ? -errno : -EIO;
+                return errno_or_else(EIO);
 
         if (k != l && k != l + accept_extra_nl)
                 return 0;
@@ -382,7 +382,7 @@ int read_full_stream_full(
                         l += k;
 
                 if (ferror(f)) {
-                        r = errno > 0 ? -errno : -EIO;
+                        r = errno_or_else(EIO);
                         goto finalize;
                 }
 
@@ -661,7 +661,7 @@ int fflush_and_check(FILE *f) {
         fflush(f);
 
         if (ferror(f))
-                return errno > 0 ? -errno : -EIO;
+                return errno_or_else(EIO);
 
         return 0;
 }
@@ -888,7 +888,7 @@ int safe_fgetc(FILE *f, char *ret) {
         k = fgetc(f);
         if (k == EOF) {
                 if (ferror(f))
-                        return errno > 0 ? -errno : -EIO;
+                        return errno_or_else(EIO);
 
                 if (ret)
                         *ret = 0;
diff --git a/src/basic/glob-util.c b/src/basic/glob-util.c
index 32c53f8c73..b335af8d97 100644
--- a/src/basic/glob-util.c
+++ b/src/basic/glob-util.c
@@ -8,6 +8,7 @@
 #include <unistd.h>
 
 #include "dirent-util.h"
+#include "errno-util.h"
 #include "glob-util.h"
 #include "macro.h"
 #include "path-util.h"
@@ -36,13 +37,12 @@ int safe_glob(const char *path, int flags, glob_t *pglob) {
 
         errno = 0;
         k = glob(path, flags | GLOB_ALTDIRFUNC, NULL, pglob);
-
         if (k == GLOB_NOMATCH)
                 return -ENOENT;
         if (k == GLOB_NOSPACE)
                 return -ENOMEM;
         if (k != 0)
-                return errno > 0 ? -errno : -EIO;
+                return errno_or_else(EIO);
         if (strv_isempty(pglob->gl_pathv))
                 return -ENOENT;
 
diff --git a/src/basic/in-addr-util.c b/src/basic/in-addr-util.c
index c1fab51b5e..7a5384bab3 100644
--- a/src/basic/in-addr-util.c
+++ b/src/basic/in-addr-util.c
@@ -9,6 +9,7 @@
 #include <stdlib.h>
 
 #include "alloc-util.h"
+#include "errno-util.h"
 #include "in-addr-util.h"
 #include "macro.h"
 #include "parse-util.h"
@@ -315,7 +316,7 @@ int in_addr_to_string(int family, const union in_addr_union *u, char **ret) {
 
         errno = 0;
         if (!inet_ntop(family, u, x, l))
-                return errno > 0 ? -errno : -EINVAL;
+                return errno_or_else(EINVAL);
 
         *ret = TAKE_PTR(x);
         return 0;
@@ -345,7 +346,7 @@ int in_addr_prefix_to_string(int family, const union in_addr_union *u, unsigned
 
         errno = 0;
         if (!inet_ntop(family, u, x, l))
-                return errno > 0 ? -errno : -EINVAL;
+                return errno_or_else(EINVAL);
 
         p = x + strlen(x);
         l -= strlen(x);
@@ -384,7 +385,7 @@ int in_addr_ifindex_to_string(int family, const union in_addr_union *u, int ifin
 
         errno = 0;
         if (!inet_ntop(family, u, x, l))
-                return errno > 0 ? -errno : -EINVAL;
+                return errno_or_else(EINVAL);
 
         sprintf(strchr(x, 0), "%%%i", ifindex);
 
@@ -404,7 +405,7 @@ int in_addr_from_string(int family, const char *s, union in_addr_union *ret) {
 
         errno = 0;
         if (inet_pton(family, s, ret ?: &buffer) <= 0)
-                return errno > 0 ? -errno : -EINVAL;
+                return errno_or_else(EINVAL);
 
         return 0;
 }
diff --git a/src/basic/socket-util.c b/src/basic/socket-util.c
index e1636bca6e..82bda64801 100644
--- a/src/basic/socket-util.c
+++ b/src/basic/socket-util.c
@@ -78,7 +78,7 @@ int socket_address_parse(SocketAddress *a, const char *s) {
 
                 errno = 0;
                 if (inet_pton(AF_INET6, n, &a->sockaddr.in6.sin6_addr) <= 0)
-                        return errno > 0 ? -errno : -EINVAL;
+                        return errno_or_else(EINVAL);
 
                 e++;
                 if (*e != ':')
diff --git a/src/basic/user-util.c b/src/basic/user-util.c
index 1dd8e11e9e..b8eb894f40 100644
--- a/src/basic/user-util.c
+++ b/src/basic/user-util.c
@@ -15,6 +15,7 @@
 #include <utmp.h>
 
 #include "alloc-util.h"
+#include "errno-util.h"
 #include "fd-util.h"
 #include "fileio.h"
 #include "format-util.h"
@@ -213,7 +214,7 @@ int get_user_creds(
                 p = getpwnam(*username);
         }
         if (!p) {
-                r = errno > 0 ? -errno : -ESRCH;
+                r = errno_or_else(ESRCH);
 
                 /* If the user requested that we only synthesize as fallback, do so now */
                 if (FLAGS_SET(flags, USER_CREDS_PREFER_NSS)) {
@@ -307,7 +308,7 @@ int get_group_creds(const char **groupname, gid_t *gid, UserCredsFlags flags) {
         }
 
         if (!g)
-                return errno > 0 ? -errno : -ESRCH;
+                return errno_or_else(ESRCH);
 
         if (gid) {
                 if (!gid_is_valid(g->gr_gid))
@@ -492,7 +493,7 @@ int get_home_dir(char **_h) {
         errno = 0;
         p = getpwuid(u);
         if (!p)
-                return errno > 0 ? -errno : -ESRCH;
+                return errno_or_else(ESRCH);
 
         if (!path_is_valid(p->pw_dir) ||
             !path_is_absolute(p->pw_dir))
@@ -549,7 +550,7 @@ int get_shell(char **_s) {
         errno = 0;
         p = getpwuid(u);
         if (!p)
-                return errno > 0 ? -errno : -ESRCH;
+                return errno_or_else(ESRCH);
 
         if (!path_is_valid(p->pw_shell) ||
             !path_is_absolute(p->pw_shell))
@@ -770,7 +771,7 @@ int putpwent_sane(const struct passwd *pw, FILE *stream) {
 
         errno = 0;
         if (putpwent(pw, stream) != 0)
-                return errno > 0 ? -errno : -EIO;
+                return errno_or_else(EIO);
 
         return 0;
 }
@@ -781,7 +782,7 @@ int putspent_sane(const struct spwd *sp, FILE *stream) {
 
         errno = 0;
         if (putspent(sp, stream) != 0)
-                return errno > 0 ? -errno : -EIO;
+                return errno_or_else(EIO);
 
         return 0;
 }
@@ -792,7 +793,7 @@ int putgrent_sane(const struct group *gr, FILE *stream) {
 
         errno = 0;
         if (putgrent(gr, stream) != 0)
-                return errno > 0 ? -errno : -EIO;
+                return errno_or_else(EIO);
 
         return 0;
 }
@@ -804,7 +805,7 @@ int putsgent_sane(const struct sgrp *sg, FILE *stream) {
 
         errno = 0;
         if (putsgent(sg, stream) != 0)
-                return errno > 0 ? -errno : -EIO;
+                return errno_or_else(EIO);
 
         return 0;
 }
@@ -819,7 +820,7 @@ int fgetpwent_sane(FILE *stream, struct passwd **pw) {
         errno = 0;
         p = fgetpwent(stream);
         if (!p && errno != ENOENT)
-                return errno > 0 ? -errno : -EIO;
+                return errno_or_else(EIO);
 
         *pw = p;
         return !!p;
@@ -834,7 +835,7 @@ int fgetspent_sane(FILE *stream, struct spwd **sp) {
         errno = 0;
         s = fgetspent(stream);
         if (!s && errno != ENOENT)
-                return errno > 0 ? -errno : -EIO;
+                return errno_or_else(EIO);
 
         *sp = s;
         return !!s;
@@ -849,7 +850,7 @@ int fgetgrent_sane(FILE *stream, struct group **gr) {
         errno = 0;
         g = fgetgrent(stream);
         if (!g && errno != ENOENT)
-                return errno > 0 ? -errno : -EIO;
+                return errno_or_else(EIO);
 
         *gr = g;
         return !!g;
@@ -865,7 +866,7 @@ int fgetsgent_sane(FILE *stream, struct sgrp **sg) {
         errno = 0;
         s = fgetsgent(stream);
         if (!s && errno != ENOENT)
-                return errno > 0 ? -errno : -EIO;
+                return errno_or_else(EIO);
 
         *sg = s;
         return !!s;
diff --git a/src/core/dbus-cgroup.c b/src/core/dbus-cgroup.c
index f70e6c87ee..2f2313c599 100644
--- a/src/core/dbus-cgroup.c
+++ b/src/core/dbus-cgroup.c
@@ -10,6 +10,7 @@
 #include "cgroup.h"
 #include "dbus-cgroup.h"
 #include "dbus-util.h"
+#include "errno-util.h"
 #include "fd-util.h"
 #include "fileio.h"
 #include "limits-util.h"
@@ -1492,7 +1493,7 @@ int bus_cgroup_set_property(
 
                                 errno = 0;
                                 if (!inet_ntop(item->family, &item->address, buffer, sizeof(buffer)))
-                                        return errno > 0 ? -errno : -EINVAL;
+                                        return errno_or_else(EINVAL);
 
                                 fprintf(f, "%s=%s/%u\n", name, buffer, item->prefixlen);
                         }
diff --git a/src/core/dynamic-user.c b/src/core/dynamic-user.c
index c380bee9e5..fb0a794348 100644
--- a/src/core/dynamic-user.c
+++ b/src/core/dynamic-user.c
@@ -494,7 +494,7 @@ static int dynamic_user_realize(
                 errno = 0;
                 p = getpwuid(num);
                 if (!p)
-                        return errno > 0 ? -errno : -ESRCH;
+                        return errno_or_else(ESRCH);
 
                 gid = p->pw_gid;
         }
diff --git a/src/core/execute.c b/src/core/execute.c
index 36a6641421..d8137090ed 100644
--- a/src/core/execute.c
+++ b/src/core/execute.c
@@ -999,12 +999,8 @@ static int get_supplementary_groups(const ExecContext *c, const char *user,
          */
         errno = 0;
         ngroups_max = (int) sysconf(_SC_NGROUPS_MAX);
-        if (ngroups_max <= 0) {
-                if (errno > 0)
-                        return -errno;
-                else
-                        return -EOPNOTSUPP; /* For all other values */
-        }
+        if (ngroups_max <= 0)
+                return errno_or_else(EOPNOTSUPP);
 
         l_gids = new(gid_t, ngroups_max);
         if (!l_gids)
diff --git a/src/getty-generator/getty-generator.c b/src/getty-generator/getty-generator.c
index 8610ab6705..4563daf3ad 100644
--- a/src/getty-generator/getty-generator.c
+++ b/src/getty-generator/getty-generator.c
@@ -6,6 +6,7 @@
 #include <unistd.h>
 
 #include "alloc-util.h"
+#include "errno-util.h"
 #include "fd-util.h"
 #include "fileio.h"
 #include "generator.h"
@@ -94,7 +95,7 @@ static int verify_tty(const char *name) {
 
         errno = 0;
         if (isatty(fd) <= 0)
-                return errno > 0 ? -errno : -EIO;
+                return errno_or_else(EIO);
 
         return 0;
 }
diff --git a/src/login/logind-core.c b/src/login/logind-core.c
index dacd3b3d9c..f631ba7219 100644
--- a/src/login/logind-core.c
+++ b/src/login/logind-core.c
@@ -17,6 +17,7 @@
 #include "cgroup-util.h"
 #include "conf-parser.h"
 #include "device-util.h"
+#include "errno-util.h"
 #include "fd-util.h"
 #include "limits-util.h"
 #include "logind.h"
@@ -191,7 +192,7 @@ int manager_add_user_by_uid(Manager *m, uid_t uid, User **_user) {
         errno = 0;
         p = getpwuid(uid);
         if (!p)
-                return errno > 0 ? -errno : -ENOENT;
+                return errno_or_else(ENOENT);
 
         return manager_add_user(m, uid, p->pw_gid, p->pw_name, p->pw_dir, _user);
 }
diff --git a/src/login/logind-dbus.c b/src/login/logind-dbus.c
index 0e8925ab94..1f5bdfecfc 100644
--- a/src/login/logind-dbus.c
+++ b/src/login/logind-dbus.c
@@ -1242,7 +1242,7 @@ static int method_set_user_linger(sd_bus_message *message, void *userdata, sd_bu
         errno = 0;
         pw = getpwuid(uid);
         if (!pw)
-                return errno > 0 ? -errno : -ENOENT;
+                return errno_or_else(ENOENT);
 
         r = bus_verify_polkit_async(
                         message,
diff --git a/src/machine/machine.c b/src/machine/machine.c
index ef8ccd98fb..b203a1dde8 100644
--- a/src/machine/machine.c
+++ b/src/machine/machine.c
@@ -11,6 +11,7 @@
 #include "bus-error.h"
 #include "bus-util.h"
 #include "env-file.h"
+#include "errno-util.h"
 #include "escape.h"
 #include "extract-word.h"
 #include "fd-util.h"
@@ -620,7 +621,7 @@ int machine_get_uid_shift(Machine *m, uid_t *ret) {
         k = fscanf(f, UID_FMT " " UID_FMT " " UID_FMT "\n", &uid_base, &uid_shift, &uid_range);
         if (k != 3) {
                 if (ferror(f))
-                        return -errno;
+                        return errno_or_else(EIO);
 
                 return -EBADMSG;
         }
@@ -651,7 +652,7 @@ int machine_get_uid_shift(Machine *m, uid_t *ret) {
         k = fscanf(f, GID_FMT " " GID_FMT " " GID_FMT "\n", &gid_base, &gid_shift, &gid_range);
         if (k != 3) {
                 if (ferror(f))
-                        return -errno;
+                        return errno_or_else(EIO);
 
                 return -EBADMSG;
         }
diff --git a/src/machine/machined-dbus.c b/src/machine/machined-dbus.c
index fea9cc2633..8031dafe15 100644
--- a/src/machine/machined-dbus.c
+++ b/src/machine/machined-dbus.c
@@ -11,6 +11,7 @@
 #include "bus-common-errors.h"
 #include "bus-util.h"
 #include "cgroup-util.h"
+#include "errno-util.h"
 #include "fd-util.h"
 #include "fileio.h"
 #include "format-util.h"
@@ -625,7 +626,7 @@ static int clean_pool_done(Operation *operation, int ret, sd_bus_error *error) {
         errno = 0;
         n = fread(&success, 1, sizeof(success), f);
         if (n != sizeof(success))
-                return ret < 0 ? ret : (errno != 0 ? -errno : -EIO);
+                return ret < 0 ? ret : errno_or_else(EIO);
 
         if (ret < 0) {
                 _cleanup_free_ char *name = NULL;
@@ -669,7 +670,7 @@ static int clean_pool_done(Operation *operation, int ret, sd_bus_error *error) {
                 errno = 0;
                 n = fread(&size, 1, sizeof(size), f);
                 if (n != sizeof(size))
-                        return errno != 0 ? -errno : -EIO;
+                        return errno_or_else(EIO);
 
                 r = sd_bus_message_append(reply, "(st)", name, size);
                 if (r < 0)
@@ -914,8 +915,8 @@ static int method_map_from_machine_user(sd_bus_message *message, void *userdata,
                 if (k < 0 && feof(f))
                         break;
                 if (k != 3) {
-                        if (ferror(f) && errno > 0)
-                                return -errno;
+                        if (ferror(f))
+                                return errno_or_else(EIO);
 
                         return -EIO;
                 }
@@ -972,8 +973,8 @@ static int method_map_to_machine_user(sd_bus_message *message, void *userdata, s
                         if (k < 0 && feof(f))
                                 break;
                         if (k != 3) {
-                                if (ferror(f) && errno > 0)
-                                        return -errno;
+                                if (ferror(f))
+                                        return errno_or_else(EIO);
 
                                 return -EIO;
                         }
@@ -1036,8 +1037,8 @@ static int method_map_from_machine_group(sd_bus_message *message, void *groupdat
                 if (k < 0 && feof(f))
                         break;
                 if (k != 3) {
-                        if (ferror(f) && errno > 0)
-                                return -errno;
+                        if (ferror(f))
+                                return errno_or_else(EIO);
 
                         return -EIO;
                 }
@@ -1094,8 +1095,8 @@ static int method_map_to_machine_group(sd_bus_message *message, void *groupdata,
                         if (k < 0 && feof(f))
                                 break;
                         if (k != 3) {
-                                if (ferror(f) && errno > 0)
-                                        return -errno;
+                                if (ferror(f))
+                                        return errno_or_else(EIO);
 
                                 return -EIO;
                         }
diff --git a/src/shared/dissect-image.c b/src/shared/dissect-image.c
index 030e12e4ee..a54714169e 100644
--- a/src/shared/dissect-image.c
+++ b/src/shared/dissect-image.c
@@ -60,7 +60,7 @@ int probe_filesystem(const char *node, char **ret_fstype) {
         errno = 0;
         b = blkid_new_probe_from_filename(node);
         if (!b)
-                return -errno ?: -ENOMEM;
+                return errno_or_else(ENOMEM);
 
         blkid_probe_enable_superblocks(b, 1);
         blkid_probe_set_superblocks_flags(b, BLKID_SUBLKS_TYPE);
@@ -76,7 +76,7 @@ int probe_filesystem(const char *node, char **ret_fstype) {
                 return -EUCLEAN;
         }
         if (r != 0)
-                return -errno ?: -EIO;
+                return errno_or_else(EIO);
 
         (void) blkid_probe_lookup_value(b, "TYPE", &fstype, NULL);
 
@@ -333,7 +333,7 @@ int dissect_image(
         errno = 0;
         r = blkid_probe_set_device(b, fd, 0, 0);
         if (r != 0)
-                return -errno ?: -ENOMEM;
+                return errno_or_else(ENOMEM);
 
         if ((flags & DISSECT_IMAGE_GPT_ONLY) == 0) {
                 /* Look for file system superblocks, unless we only shall look for GPT partition tables */
@@ -349,7 +349,7 @@ int dissect_image(
         if (IN_SET(r, -2, 1))
                 return log_debug_errno(SYNTHETIC_ERRNO(ENOPKG), "Failed to identify any partition table.");
         if (r != 0)
-                return -errno ?: -EIO;
+                return errno_or_else(EIO);
 
         m = new0(DissectedImage, 1);
         if (!m)
@@ -415,7 +415,7 @@ int dissect_image(
         errno = 0;
         pl = blkid_probe_get_partitions(b);
         if (!pl)
-                return -errno ?: -ENOMEM;
+                return errno_or_else(ENOMEM);
 
         r = loop_wait_for_partitions_to_appear(fd, d, blkid_partlist_numof_partitions(pl), flags, &e);
         if (r < 0)
diff --git a/src/udev/udev-builtin-blkid.c b/src/udev/udev-builtin-blkid.c
index efbb0732f1..7ef75e6f91 100644
--- a/src/udev/udev-builtin-blkid.c
+++ b/src/udev/udev-builtin-blkid.c
@@ -20,6 +20,7 @@
 #include "blkid-util.h"
 #include "device-util.h"
 #include "efivars.h"
+#include "errno-util.h"
 #include "fd-util.h"
 #include "gpt.h"
 #include "parse-util.h"
@@ -113,7 +114,7 @@ static int find_gpt_root(sd_device *dev, blkid_probe pr, bool test) {
         errno = 0;
         pl = blkid_probe_get_partitions(pr);
         if (!pl)
-                return -errno ?: -ENOMEM;
+                return errno_or_else(ENOMEM);
 
         nvals = blkid_partlist_numof_partitions(pl);
         for (i = 0; i < nvals; i++) {