4 files changed, 38 insertions, 4 deletions
diff --git a/src/basic/refcnt.h b/src/basic/refcnt.h
index 0502c20a2e..8a39d69fe4 100644
--- a/src/basic/refcnt.h
+++ b/src/basic/refcnt.h
@@ -21,7 +21,9 @@
   along with systemd; If not, see <http://www.gnu.org/licenses/>.
 ***/
 
-/* A type-safe atomic refcounter */
+/* A type-safe atomic refcounter.
+ *
+ * DO NOT USE THIS UNLESS YOU ACTUALLY CARE ABOUT THREAD SAFETY! */
 
 typedef struct {
         volatile unsigned _value;
diff --git a/src/basic/ring.h b/src/basic/ring.h
index a7c44d1b56..dbd6296384 100644
--- a/src/basic/ring.h
+++ b/src/basic/ring.h
@@ -50,7 +50,6 @@ int ring_push(Ring *r, const void *u8, size_t size);
 void ring_pull(Ring *r, size_t size);
 
 /* return size of occupied buffer in bytes */
-static inline size_t ring_get_size(Ring *r)
-{
+static inline size_t ring_get_size(Ring *r) {
         return r->used;
 }
diff --git a/src/basic/time-util.c b/src/basic/time-util.c
index e278196c90..3d8d5d7568 100644
--- a/src/basic/time-util.c
+++ b/src/basic/time-util.c
@@ -26,6 +26,7 @@
 
 #include "util.h"
 #include "time-util.h"
+#include "path-util.h"
 #include "strv.h"
 
 usec_t now(clockid_t clock_id) {
@@ -971,7 +972,10 @@ bool timezone_is_valid(const char *name) {
         const char *p, *t;
         struct stat st;
 
-        if (!name || *name == 0 || *name == '/')
+        if (isempty(name))
+                return false;
+
+        if (name[0] == '/')
                 return false;
 
         for (p = name; *p; p++) {
@@ -1021,3 +1025,30 @@ clockid_t clock_boottime_or_monotonic(void) {
 
         return clock;
 }
+
+int get_timezone(char **timezone) {
+        _cleanup_free_ char *t = NULL;
+        const char *e;
+        char *z;
+        int r;
+
+        r = readlink_malloc("/etc/localtime", &t);
+        if (r < 0)
+                return r; /* returns EINVAL if not a symlink */
+
+        e = path_startswith(t, "/usr/share/zoneinfo/");
+        if (!e)
+                e = path_startswith(t, "../usr/share/zoneinfo/");
+        if (!e)
+                return -EINVAL;
+
+        if (!timezone_is_valid(e))
+                return -EINVAL;
+
+        z = strdup(e);
+        if (!z)
+                return -ENOMEM;
+
+        *timezone = z;
+        return 0;
+}
diff --git a/src/basic/time-util.h b/src/basic/time-util.h
index 2aba042217..03a47f310d 100644
--- a/src/basic/time-util.h
+++ b/src/basic/time-util.h
@@ -110,3 +110,5 @@ bool timezone_is_valid(const char *name);
 clockid_t clock_boottime_or_monotonic(void);
 
 #define xstrftime(buf, fmt, tm) assert_se(strftime(buf, ELEMENTSOF(buf), fmt, tm) > 0)
+
+int get_timezone(char **timezone);