1 files changed, 51 insertions, 0 deletions
diff --git a/src/util.c b/src/util.c
index b4c5e2e65a..3179502f6c 100644
--- a/src/util.c
+++ b/src/util.c
@@ -1119,6 +1119,57 @@ int get_process_exe(pid_t pid, char **name) {
         return r;
 }
 
+int get_process_uid(pid_t pid, uid_t *uid) {
+        char *p;
+        FILE *f;
+        int r;
+
+        assert(uid);
+
+        if (pid == 0)
+                return getuid();
+
+        if (asprintf(&p, "/proc/%lu/status", (unsigned long) pid) < 0)
+                return -ENOMEM;
+
+        f = fopen(p, "re");
+        free(p);
+
+        if (!f)
+                return -errno;
+
+        while (!feof(f)) {
+                char line[LINE_MAX], *l;
+
+                if (!fgets(line, sizeof(line), f)) {
+                        if (feof(f))
+                                break;
+
+                        r = -errno;
+                        goto finish;
+                }
+
+                l = strstrip(line);
+
+                if (startswith(l, "Uid:")) {
+                        l += 4;
+                        l += strspn(l, WHITESPACE);
+
+                        l[strcspn(l, WHITESPACE)] = 0;
+
+                        r = parse_uid(l, uid);
+                        goto finish;
+                }
+        }
+
+        r = -EIO;
+
+finish:
+        fclose(f);
+
+        return r;
+}
+
 char *strnappend(const char *s, const char *suffix, size_t b) {
         size_t a;
         char *r;