cg_shift_path(): Do not shift if cgroup and root are equal

[elogind.git] / src / basic / cgroup-util.c

diff --git a/src/basic/cgroup-util.c b/src/basic/cgroup-util.c
index cd5db6f69c1ab46ed94efdb01bc43a12217a6766..f7a892380a7e4975dd439ca22e0470e251ca6c70 100644 (file)
--- a/src/basic/cgroup-util.c
+++ b/src/basic/cgroup-util.c
@@ -297,6 +297,10 @@ int cg_migrate(const char *cfrom, const char *pfrom, const char *cto, const char
 
         my_pid = getpid();
 
+        log_debug_elogind("Migrating \"%s\"/\"%s\" to \"%s\"/\"%s\" (%s)",
+                          cfrom, pfrom, cto, pto,
+                          ignore_self ? "ignoring self" : "watching self");
+
         do {
                 _cleanup_fclose_ FILE *f = NULL;
                 pid_t pid = 0;
@@ -570,7 +574,7 @@ static int controller_is_accessible(const char *controller) {
                  * the unified hierarchy. */
 
                 if (streq(controller, ELOGIND_CGROUP_CONTROLLER))
-                return 0;
+                        return 0;
 
                 if (startswith(controller, "name="))
                         return -EOPNOTSUPP;
@@ -581,8 +585,8 @@ static int controller_is_accessible(const char *controller) {
                 dn = controller_to_dirname(controller);
                 cc = strjoina("/sys/fs/cgroup/", dn);
 
-        if (laccess(cc, F_OK) < 0)
-                return -errno;
+                if (laccess(cc, F_OK) < 0)
+                        return -errno;
         }
 
         return 0;
@@ -811,11 +815,11 @@ int cg_pid_get_path(const char *controller, pid_t pid, char **path) {
         if (unified < 0)
                 return unified;
         if (unified == 0) {
-        if (controller) {
-                if (!cg_controller_is_valid(controller))
-                        return -EINVAL;
-        } else
-                controller = ELOGIND_CGROUP_CONTROLLER;
+                if (controller) {
+                        if (!cg_controller_is_valid(controller))
+                                return -EINVAL;
+                } else
+                        controller = ELOGIND_CGROUP_CONTROLLER;
 
                 cs = strlen(controller);
         }
@@ -840,29 +844,29 @@ int cg_pid_get_path(const char *controller, pid_t pid, char **path) {
                                 continue;
                 } else {
                         char *l;
-                size_t k;
-                const char *word, *state;
-                bool found = false;
+                        size_t k;
+                        const char *word, *state;
+                        bool found = false;
 
-                l = strchr(line, ':');
-                if (!l)
-                        continue;
+                        l = strchr(line, ':');
+                        if (!l)
+                                continue;
 
-                l++;
-                e = strchr(l, ':');
-                if (!e)
-                        continue;
+                        l++;
+                        e = strchr(l, ':');
+                        if (!e)
+                                continue;
 
-                *e = 0;
-                FOREACH_WORD_SEPARATOR(word, k, l, ",", state) {
-                        if (k == cs && memcmp(word, controller, cs) == 0) {
-                                found = true;
-                                break;
+                        *e = 0;
+                        FOREACH_WORD_SEPARATOR(word, k, l, ",", state) {
+                                if (k == cs && memcmp(word, controller, cs) == 0) {
+                                        found = true;
+                                        break;
+                                }
                         }
-                }
 
-                if (!found)
-                        continue;
+                        if (!found)
+                                continue;
                 }
 
                 p = strdup(e + 1);
@@ -1199,10 +1203,11 @@ int cg_shift_path(const char *cgroup, const char *root, const char **shifted) {
                         return r;
 
                 root = rt;
+                log_debug_elogind("Determined root path: \"%s\"", root);
         }
 
         p = path_startswith(cgroup, root);
-        if (p && p > cgroup)
+        if (p && p[0] && (p > cgroup))
                 *shifted = p - 1;
         else
                 *shifted = cgroup;
@@ -1222,6 +1227,8 @@ int cg_pid_get_path_shifted(pid_t pid, const char *root, char **cgroup) {
         if (r < 0)
                 return r;
 
+        log_debug_elogind("Shifting path: \"%s\" (PID %u, root: \"%s\")",
+                          raw, pid, root ? root : "NULL");
         r = cg_shift_path(raw, root, &c);
         if (r < 0)
                 return r;
@@ -1238,6 +1245,7 @@ int cg_pid_get_path_shifted(pid_t pid, const char *root, char **cgroup) {
 
                 *cgroup = n;
         }
+        log_debug_elogind("Resulting cgroup:\"%s\"", *cgroup);
 
         return 0;
 }
@@ -1522,6 +1530,7 @@ int cg_path_get_session(const char *path, char **session) {
         const char *e, *n, *start;
 
         assert(path);
+        log_debug_elogind("path is \"%s\"", path);
         assert(path[0] == '/');
 
         e = path + 1;
@@ -1539,6 +1548,7 @@ int cg_path_get_session(const char *path, char **session) {
         if (session) {
                 char *rr;
 
+                log_debug_elogind("found session: \"%s\"", start);
                 rr = strdup(start);
                 if (!rr)
                         return -ENOMEM;