mountpoint-util: introduce path_is_mount_point_full

src/basic/mountpoint-util.c

@@ -329,34 +329,33 @@ fallback_fstat:
 }
 
 /* flags can be AT_SYMLINK_FOLLOW or 0 */
-int path_is_mount_point(const char *t, const char *root, int flags) {
+int path_is_mount_point_full(const char *path, const char *root, int flags) {
         _cleanup_free_ char *canonical = NULL;
         _cleanup_close_ int fd = -EBADF;
         int r;
 
-        assert(t);
+        assert(path);
         assert((flags & ~AT_SYMLINK_FOLLOW) == 0);
 
-        if (path_equal(t, "/"))
+        if (path_equal(path, "/"))
                 return 1;
 
-        /* we need to resolve symlinks manually, we can't just rely on
-         * fd_is_mount_point() to do that for us; if we have a structure like
-         * /bin -> /usr/bin/ and /usr is a mount point, then the parent that we
+        /* we need to resolve symlinks manually, we can't just rely on fd_is_mount_point() to do that for us;
+         * if we have a structure like /bin -> /usr/bin/ and /usr is a mount point, then the parent that we
          * look at needs to be /usr, not /. */
-        if (flags & AT_SYMLINK_FOLLOW) {
-                r = chase(t, root, CHASE_TRAIL_SLASH, &canonical, NULL);
+        if (FLAGS_SET(flags, AT_SYMLINK_FOLLOW)) {
+                r = chase(path, root, CHASE_TRAIL_SLASH, &canonical, NULL);
                 if (r < 0)
                         return r;
 
-                t = canonical;
+                path = canonical;
         }
 
-        fd = open_parent(t, O_PATH|O_CLOEXEC, 0);
+        fd = open_parent(path, O_PATH|O_CLOEXEC, 0);
         if (fd < 0)
                 return fd;
 
-        return fd_is_mount_point(fd, last_path_component(t), flags);
+        return fd_is_mount_point(fd, last_path_component(path), flags);
 }
 
 int path_get_mnt_id_at_fallback(int dir_fd, const char *path, int *ret) {

src/basic/mountpoint-util.h

@@ -3,6 +3,7 @@
 
 #include <fcntl.h>
 #include <stdbool.h>
+#include <stddef.h>
 #include <sys/types.h>
 
 /* The limit used for /dev itself. 4MB should be enough since device nodes and symlinks don't
@@ -44,7 +45,10 @@ static inline int path_get_mnt_id(const char *path, int *ret) {
 }
 
 int fd_is_mount_point(int fd, const char *filename, int flags);
-int path_is_mount_point(const char *path, const char *root, int flags);
+int path_is_mount_point_full(const char *path, const char *root, int flags);
+static inline int path_is_mount_point(const char *path) {
+        return path_is_mount_point_full(path, NULL, 0);
+}
 
 bool fstype_is_network(const char *fstype);
 bool fstype_needs_quota(const char *fstype);

src/core/automount.c

@@ -821,7 +821,7 @@ static int automount_start(Unit *u) {
         assert(a);
         assert(IN_SET(a->state, AUTOMOUNT_DEAD, AUTOMOUNT_FAILED));
 
-        if (path_is_mount_point(a->where, NULL, 0) > 0)
+        if (path_is_mount_point(a->where) > 0)
                 return log_unit_error_errno(u, SYNTHETIC_ERRNO(EEXIST), "Path %s is already a mount point, refusing start.", a->where);
 
         r = unit_test_trigger_loaded(u);

src/core/exec-credential.c

@@ -777,7 +777,7 @@ static int setup_credentials_internal(
         assert(workspace);
 
         if (reuse_workspace) {
-                r = path_is_mount_point(workspace, NULL, 0);
+                r = path_is_mount_point(workspace);
                 if (r < 0)
                         return r;
                 if (r > 0)
@@ -788,7 +788,7 @@ static int setup_credentials_internal(
         } else
                 workspace_mounted = -1; /* ditto */
 
-        r = path_is_mount_point(final, NULL, 0);
+        r = path_is_mount_point(final);
         if (r < 0)
                 return r;
         if (r > 0) {

src/core/import-creds.c

@@ -80,7 +80,7 @@ static int acquire_credential_directory(ImportCredentialContext *c, const char *
         if (c->target_dir_fd >= 0)
                 return c->target_dir_fd;
 
-        r = path_is_mount_point(path, NULL, 0);
+        r = path_is_mount_point(path);
         if (r < 0) {
                 if (r != -ENOENT)
                         return log_error_errno(r, "Failed to determine if %s is a mount point: %m", path);

src/core/namespace.c

@@ -1117,7 +1117,7 @@ static int mount_bind_dev(const MountEntry *m) {
 
         (void) mkdir_p_label(mount_entry_path(m), 0755);
 
-        r = path_is_mount_point(mount_entry_path(m), NULL, 0);
+        r = path_is_mount_point(mount_entry_path(m));
         if (r < 0)
                 return log_debug_errno(r, "Unable to determine whether /dev is already mounted: %m");
         if (r > 0) /* make this a NOP if /dev is already a mount point */
@@ -1137,7 +1137,7 @@ static int mount_bind_sysfs(const MountEntry *m) {
 
         (void) mkdir_p_label(mount_entry_path(m), 0755);
 
-        r = path_is_mount_point(mount_entry_path(m), NULL, 0);
+        r = path_is_mount_point(mount_entry_path(m));
         if (r < 0)
                 return log_debug_errno(r, "Unable to determine whether /sys is already mounted: %m");
         if (r > 0) /* make this a NOP if /sys is already a mount point */
@@ -1184,7 +1184,7 @@ static int mount_private_apivfs(
                 /* When we do not have enough privileges to mount a new instance, fall back to use an
                  * existing mount. */
 
-                r = path_is_mount_point(entry_path, /* root = */ NULL, /* flags = */ 0);
+                r = path_is_mount_point(entry_path);
                 if (r < 0)
                         return log_debug_errno(r, "Unable to determine whether '%s' is already mounted: %m", entry_path);
                 if (r > 0)
@@ -1299,7 +1299,7 @@ static int mount_run(const MountEntry *m) {
 
         assert(m);
 
-        r = path_is_mount_point(mount_entry_path(m), NULL, 0);
+        r = path_is_mount_point(mount_entry_path(m));
         if (r < 0 && r != -ENOENT)
                 return log_debug_errno(r, "Unable to determine whether /run is already mounted: %m");
         if (r > 0) /* make this a NOP if /run is already a mount point */
@@ -1533,7 +1533,7 @@ static int apply_one_mount(
         case MOUNT_READ_WRITE_IMPLICIT:
         case MOUNT_EXEC:
         case MOUNT_NOEXEC:
-                r = path_is_mount_point(mount_entry_path(m), root_directory, 0);
+                r = path_is_mount_point_full(mount_entry_path(m), root_directory, /* flags = */ 0);
                 if (r == -ENOENT && m->ignore)
                         return 0;
                 if (r < 0)
@@ -2537,7 +2537,7 @@ int setup_namespace(const NamespaceParameters *p, char **error_path) {
         } else if (p->root_directory) {
 
                 /* A root directory is specified. Turn its directory into bind mount, if it isn't one yet. */
-                r = path_is_mount_point(root, NULL, AT_SYMLINK_FOLLOW);
+                r = path_is_mount_point_full(root, /* root = */ NULL, AT_SYMLINK_FOLLOW);
                 if (r < 0)
                         return log_debug_errno(r, "Failed to detect that %s is a mount point or not: %m", root);
                 if (r == 0) {

src/gpt-auto-generator/gpt-auto-generator.c

@@ -280,7 +280,7 @@ static int path_is_busy(const char *where) {
         assert(where);
 
         /* already a mountpoint; generators run during reload */
-        r = path_is_mount_point(where, NULL, AT_SYMLINK_FOLLOW);
+        r = path_is_mount_point_full(where, /* root = */ NULL, AT_SYMLINK_FOLLOW);
         if (r > 0)
                 return false;
         /* The directory will be created by the mount or automount unit when it is started. */

src/home/user-record-util.c

@@ -428,7 +428,7 @@ int user_record_test_home_directory(UserRecord *h) {
         if (r == 0)
                 return -ENOTDIR;
 
-        r = path_is_mount_point(hd, NULL, 0);
+        r = path_is_mount_point(hd);
         if (r < 0)
                 return r;
         if (r > 0)

src/libsystemd/sd-device/test-device-util.c

@@ -82,7 +82,7 @@ TEST(device_is_devtype) {
 }
 
 static int intro(void) {
-        if (path_is_mount_point("/sys", NULL, 0) <= 0)
+        if (path_is_mount_point("/sys") <= 0)
                 return log_tests_skipped("/sys is not mounted");
 
         return EXIT_SUCCESS;

src/libsystemd/sd-device/test-sd-device-monitor.c

@@ -299,7 +299,7 @@ int main(int argc, char *argv[]) {
         if (getuid() != 0)
                 return log_tests_skipped("not root");
 
-        if (path_is_mount_point("/sys", NULL, 0) <= 0)
+        if (path_is_mount_point("/sys") <= 0)
                 return log_tests_skipped("/sys is not mounted");
 
         if (path_is_read_only_fs("/sys") > 0)

src/libsystemd/sd-device/test-sd-device.c

@@ -677,7 +677,7 @@ TEST(devname_from_devnum) {
 }
 
 static int intro(void) {
-        if (path_is_mount_point("/sys", NULL, 0) <= 0)
+        if (path_is_mount_point("/sys") <= 0)
                 return log_tests_skipped("/sys is not mounted");
 
         return EXIT_SUCCESS;

src/login/user-runtime-dir.c

@@ -67,7 +67,7 @@ static int user_mkdir_runtime_path(
         if (r < 0)
                 return log_error_errno(r, "Failed to create /run/user: %m");
 
-        if (path_is_mount_point(runtime_path, NULL, 0) > 0)
+        if (path_is_mount_point(runtime_path) > 0)
                 log_debug("%s is already a mount point", runtime_path);
         else {
                 char options[sizeof("mode=0700,uid=,gid=,size=,nr_inodes=,smackfsroot=*")

src/nspawn/nspawn-cgroup.c

@@ -265,7 +265,7 @@ static int mount_legacy_cgroup_hierarchy(
 
         to = strjoina(strempty(dest), "/sys/fs/cgroup/", hierarchy);
 
-        r = path_is_mount_point(to, dest, 0);
+        r = path_is_mount_point_full(to, dest, /* flags = */ 0);
         if (r < 0 && r != -ENOENT)
                 return log_error_errno(r, "Failed to determine if %s is mounted already: %m", to);
         if (r > 0)
@@ -317,7 +317,7 @@ static int mount_legacy_cgns_supported(
         (void) mkdir_p(cgroup_root, 0755);
 
         /* Mount a tmpfs to /sys/fs/cgroup if it's not mounted there yet. */
-        r = path_is_mount_point(cgroup_root, dest, AT_SYMLINK_FOLLOW);
+        r = path_is_mount_point_full(cgroup_root, dest, AT_SYMLINK_FOLLOW);
         if (r < 0)
                 return log_error_errno(r, "Failed to determine if /sys/fs/cgroup is already mounted: %m");
         if (r == 0) {
@@ -427,7 +427,7 @@ static int mount_legacy_cgns_unsupported(
         (void) mkdir_p(cgroup_root, 0755);
 
         /* Mount a tmpfs to /sys/fs/cgroup if it's not mounted there yet. */
-        r = path_is_mount_point(cgroup_root, dest, AT_SYMLINK_FOLLOW);
+        r = path_is_mount_point_full(cgroup_root, dest, AT_SYMLINK_FOLLOW);
         if (r < 0)
                 return log_error_errno(r, "Failed to determine if /sys/fs/cgroup is already mounted: %m");
         if (r == 0) {
@@ -529,7 +529,7 @@ static int mount_unified_cgroups(const char *dest) {
 
         (void) mkdir_p(p, 0755);
 
-        r = path_is_mount_point(p, dest, AT_SYMLINK_FOLLOW);
+        r = path_is_mount_point_full(p, dest, AT_SYMLINK_FOLLOW);
         if (r < 0)
                 return log_error_errno(r, "Failed to determine if %s is mounted already: %m", p);
         if (r > 0) {

src/nspawn/nspawn-mount.c

@@ -642,7 +642,7 @@ int mount_all(const char *dest,
 
                 /* Skip this entry if it is not a remount. */
                 if (mount_table[k].what) {
-                        r = path_is_mount_point(where, NULL, 0);
+                        r = path_is_mount_point(where);
                         if (r < 0 && r != -ENOENT)
                                 return log_error_errno(r, "Failed to detect whether %s is a mount point: %m", where);
                         if (r > 0)

src/nspawn/nspawn.c

@@ -2560,7 +2560,7 @@ static int setup_journal(const char *directory) {
         p = strjoina("/var/log/journal/", SD_ID128_TO_STRING(arg_uuid));
         q = prefix_roota(directory, p);
 
-        if (path_is_mount_point(p, NULL, 0) > 0) {
+        if (path_is_mount_point(p) > 0) {
                 if (try)
                         return 0;
 
@@ -2568,7 +2568,7 @@ static int setup_journal(const char *directory) {
                                        "%s: already a mount point, refusing to use for journal", p);
         }
 
-        if (path_is_mount_point(q, NULL, 0) > 0) {
+        if (path_is_mount_point(q) > 0) {
                 if (try)
                         return 0;
 
@@ -3633,7 +3633,7 @@ static int setup_unix_export_dir_outside(char **ret) {
         if (!p)
                 return log_oom();
 
-        r = path_is_mount_point(p, /* root= */ NULL, 0);
+        r = path_is_mount_point(p);
         if (r > 0)
                 return log_error_errno(SYNTHETIC_ERRNO(EEXIST), "Mount point '%s' exists already, refusing.", p);
         if (r < 0 && r != -ENOENT)
@@ -5680,7 +5680,7 @@ static int run(int argc, char *argv[]) {
                         /* If the specified path is a mount point we generate the new snapshot immediately
                          * inside it under a random name. However if the specified is not a mount point we
                          * create the new snapshot in the parent directory, just next to it. */
-                        r = path_is_mount_point(arg_directory, NULL, 0);
+                        r = path_is_mount_point(arg_directory);
                         if (r < 0) {
                                 log_error_errno(r, "Failed to determine whether directory %s is mount point: %m", arg_directory);
                                 goto finish;

src/partition/growfs.c

@@ -224,7 +224,7 @@ static int run(int argc, char *argv[]) {
         if (r <= 0)
                 return r;
 
-        r = path_is_mount_point(arg_target, NULL, 0);
+        r = path_is_mount_point(arg_target);
         if (r < 0)
                 return log_error_errno(r, "Failed to check if \"%s\" is a mount point: %m", arg_target);
         if (r == 0)

src/partition/repart.c

@@ -5828,7 +5828,7 @@ static int find_backing_devno(
         if (r < 0)
                 return r;
 
-        r = path_is_mount_point(resolved, NULL, 0);
+        r = path_is_mount_point(resolved);
         if (r < 0)
                 return r;
         if (r == 0) /* Not a mount point, then it's not a partition of its own, let's not automatically use it. */
@@ -7037,7 +7037,7 @@ static int parse_argv(int argc, char *argv[]) {
                 /* By default operate on /sysusr/ or /sysroot/ when invoked in the initrd. We prefer the
                  * former, if it is mounted, so that we have deterministic behaviour on systems where /usr/
                  * is vendor-supplied but the root fs formatted on first boot. */
-                r = path_is_mount_point("/sysusr/usr", NULL, 0);
+                r = path_is_mount_point("/sysusr/usr");
                 if (r <= 0) {
                         if (r < 0 && r != -ENOENT)
                                 log_debug_errno(r, "Unable to determine whether /sysusr/usr is a mount point, assuming it is not: %m");

src/shared/condition.c

@@ -931,7 +931,7 @@ static int condition_test_path_is_mount_point(Condition *c, char **env) {
         assert(c->parameter);
         assert(c->type == CONDITION_PATH_IS_MOUNT_POINT);
 
-        return path_is_mount_point(c->parameter, NULL, AT_SYMLINK_FOLLOW) > 0;
+        return path_is_mount_point_full(c->parameter, /* root = */ NULL, AT_SYMLINK_FOLLOW) > 0;
 }
 
 static int condition_test_path_is_read_write(Condition *c, char **env) {

src/shared/machine-id-setup.c

@@ -237,7 +237,7 @@ int machine_id_commit(const char *root) {
 
         etc_machine_id = prefix_roota(root, "/etc/machine-id");
 
-        r = path_is_mount_point(etc_machine_id, NULL, 0);
+        r = path_is_mount_point(etc_machine_id);
         if (r < 0)
                 return log_error_errno(r, "Failed to determine whether %s is a mount point: %m", etc_machine_id);
         if (r == 0) {

src/shared/mount-setup.c

@@ -177,7 +177,7 @@ static int mount_one(const MountPoint *p, bool relabel) {
         if (relabel)
                 (void) label_fix(p->where, LABEL_IGNORE_ENOENT|LABEL_IGNORE_EROFS);
 
-        r = path_is_mount_point(p->where, NULL, AT_SYMLINK_FOLLOW);
+        r = path_is_mount_point_full(p->where, /* root = */ NULL, AT_SYMLINK_FOLLOW);
         if (r < 0 && r != -ENOENT) {
                 log_full_errno(priority, r, "Failed to determine whether %s is a mount point: %m", p->where);
                 return (p->mode & MNT_FATAL) ? r : 0;