X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=src%2Fshared%2Fcgroup-util.c;h=74889b636324dea71c0426e05740198a5f21286b;hb=96415cad2fdd8d280ae94b02651b5f826a2f7f3d;hp=88bc33e3d55c21e6da797a1ec30c77476ecc852e;hpb=674eb68520107d771e3458287025a73387f938c4;p=elogind.git

diff --git a/src/shared/cgroup-util.c b/src/shared/cgroup-util.c
index 88bc33e3d..74889b636 100644
--- a/src/shared/cgroup-util.c
+++ b/src/shared/cgroup-util.c
@@ -480,7 +480,7 @@ static int join_path(const char *controller, const char *path, const char *suffi
 
 int cg_get_path(const char *controller, const char *path, const char *suffix, char **fs) {
         const char *p;
-        static __thread bool good = false;
+        static thread_local bool good = false;
 
         assert(fs);
 
@@ -1082,42 +1082,42 @@ int cg_get_root_path(char **path) {
         return 0;
 }
 
-int cg_pid_get_path_shifted(pid_t pid, char **root, char **cgroup) {
+int cg_pid_get_path_shifted(pid_t pid, const char *root, char **cgroup) {
         _cleanup_free_ char *cg_root = NULL;
         char *cg_process, *p;
         int r;
 
-        r = cg_get_root_path(&cg_root);
-        if (r < 0)
-                return r;
+        assert(pid >= 0);
+        assert(cgroup);
+
+        if (!root) {
+                /* If the root was specified let's use that, otherwise
+                 * let's determine it from PID 1 */
+
+                r = cg_get_root_path(&cg_root);
+                if (r < 0)
+                        return r;
+
+                root = cg_root;
+        }
 
         r = cg_pid_get_path(SYSTEMD_CGROUP_CONTROLLER, pid, &cg_process);
         if (r < 0)
                 return r;
 
-        p = path_startswith(cg_process, cg_root);
-        if (p)
-                p--;
-        else
-                p = cg_process;
+        p = path_startswith(cg_process, root);
+        if (p) {
+                char *c;
 
-        if (cgroup) {
-                char* c;
+                c = strdup(p - 1);
+                free(cg_process);
 
-                c = strdup(p);
-                if (!c) {
-                        free(cg_process);
+                if (!c)
                         return -ENOMEM;
-                }
 
                 *cgroup = c;
-        }
-
-        if (root) {
-                cg_process[p-cg_process] = 0;
-                *root = cg_process;
         } else
-                free(cg_process);
+                *cgroup = cg_process;
 
         return 0;
 }
@@ -1183,6 +1183,9 @@ int cg_pid_get_unit(pid_t pid, char **unit) {
         return cg_path_get_unit(cgroup, unit);
 }
 
+/**
+ * Skip session-*.scope, but require it to be there.
+ */
 static const char *skip_session(const char *p) {
         size_t n;
 
@@ -1191,7 +1194,27 @@ static const char *skip_session(const char *p) {
         p += strspn(p, "/");
 
         n = strcspn(p, "/");
-        if (n <= 12 || memcmp(p, "session-", 8) != 0 || memcmp(p + n - 6, ".scope", 6) != 0)
+        if (n < strlen("session-x.scope") || memcmp(p, "session-", 8) != 0 || memcmp(p + n - 6, ".scope", 6) != 0)
+                return NULL;
+
+        p += n;
+        p += strspn(p, "/");
+
+        return p;
+}
+
+/**
+ * Skip user@*.service, but require it to be there.
+ */
+static const char *skip_user_manager(const char *p) {
+        size_t n;
+
+        assert(p);
+
+        p += strspn(p, "/");
+
+        n = strcspn(p, "/");
+        if (n < strlen("user@x.service") || memcmp(p, "user@", 5) != 0 || memcmp(p + n - 8, ".service", 8) != 0)
                 return NULL;
 
         p += n;
@@ -1201,7 +1224,7 @@ static const char *skip_session(const char *p) {
 }
 
 int cg_path_get_user_unit(const char *path, char **unit) {
-        const char *e;
+        const char *e, *t;
 
         assert(path);
         assert(unit);
@@ -1213,13 +1236,17 @@ int cg_path_get_user_unit(const char *path, char **unit) {
         /* Skip slices, if there are any */
         e = skip_slices(path);
 
-        /* Skip the session scope, require that there is one */
-        e = skip_session(e);
-        if (!e)
-                return -ENOENT;
-
-        /* And skip more slices */
-        e = skip_slices(e);
+        /* Skip the session scope... */
+        t = skip_session(e);
+        if (t)
+                /* ... and skip more slices if there's one */
+                e = skip_slices(t);
+        else {
+                /* ... or require a user manager unit to be there */
+                e = skip_user_manager(e);
+                if (!e)
+                        return -ENOENT;
+        }
 
         return cg_path_decode_unit(e, unit);
 }