manager: canonicalize search paths and filter out non-existing paths and those pointing to the same fs directory

src/manager.c

@@ -283,15 +283,33 @@ static int manager_find_paths(Manager *m) {
                 }
         }
 
+        if (m->unit_path)
+                if (!strv_path_canonicalize(m->unit_path))
+                        return -ENOMEM;
+
+        if (m->sysvinit_path)
+                if (!strv_path_canonicalize(m->sysvinit_path))
+                        return -ENOMEM;
+
+        if (m->sysvrcnd_path)
+                if (!strv_path_canonicalize(m->sysvrcnd_path))
+                        return -ENOMEM;
+
         strv_uniq(m->unit_path);
         strv_uniq(m->sysvinit_path);
         strv_uniq(m->sysvrcnd_path);
 
-        assert(!strv_isempty(m->unit_path));
-        if (!(t = strv_join(m->unit_path, "\n\t")))
-                return -ENOMEM;
-        log_debug("Looking for unit files in:\n\t%s", t);
-        free(t);
+        if (!strv_isempty(m->unit_path)) {
+
+                if (!(t = strv_join(m->unit_path, "\n\t")))
+                        return -ENOMEM;
+                log_debug("Looking for unit files in:\n\t%s", t);
+                free(t);
+        } else {
+                log_debug("Ignoring unit files.");
+                strv_free(m->unit_path);
+                m->unit_path = NULL;
+        }
 
         if (!strv_isempty(m->sysvinit_path)) {
 
@@ -300,8 +318,11 @@ static int manager_find_paths(Manager *m) {
 
                 log_debug("Looking for SysV init scripts in:\n\t%s", t);
                 free(t);
-        } else
+        } else {
                 log_debug("Ignoring SysV init scripts.");
+                strv_free(m->sysvinit_path);
+                m->sysvinit_path = NULL;
+        }
 
         if (!strv_isempty(m->sysvrcnd_path)) {
 
@@ -310,8 +331,11 @@ static int manager_find_paths(Manager *m) {
 
                 log_debug("Looking for SysV rcN.d links in:\n\t%s", t);
                 free(t);
-        } else
+        } else {
                 log_debug("Ignoring SysV rcN.d links.");
+                strv_free(m->sysvrcnd_path);
+                m->sysvrcnd_path = NULL;
+        }
 
         return 0;
 }

src/util.c

@@ -652,6 +652,51 @@ char **strv_path_make_absolute_cwd(char **l) {
         return l;
 }
 
+char **strv_path_canonicalize(char **l) {
+        char **s;
+        unsigned k = 0;
+        bool enomem = false;
+
+        if (strv_isempty(l))
+                return l;
+
+        /* Goes through every item in the string list and canonicalize
+         * the path. This works in place and won't rollback any
+         * changes on failure. */
+
+        STRV_FOREACH(s, l) {
+                char *t, *u;
+
+                t = path_make_absolute_cwd(*s);
+                free(*s);
+
+                if (!t) {
+                        enomem = true;
+                        continue;
+                }
+
+                errno = 0;
+                u = canonicalize_file_name(t);
+                free(t);
+
+                if (!u) {
+                        if (errno == ENOMEM || !errno)
+                                enomem = true;
+
+                        continue;
+                }
+
+                l[k++] = u;
+        }
+
+        l[k] = NULL;
+
+        if (enomem)
+                return NULL;
+
+        return l;
+}
+
 int reset_all_signal_handlers(void) {
         int sig;
 

src/util.h

@@ -138,7 +138,9 @@ bool is_path(const char *p);
 bool path_is_absolute(const char *p);
 char *path_make_absolute(const char *p, const char *prefix);
 char *path_make_absolute_cwd(const char *p);
+
 char **strv_path_make_absolute_cwd(char **l);
+char **strv_path_canonicalize(char **l);
 
 int reset_all_signal_handlers(void);