test-tmpfiles: actually test that the file is temporary

CID #1341451.

src/test/test-tmpfiles.c

@@ -28,6 +28,8 @@
 #include "fd-util.h"
 #include "fileio.h"
 #include "formats-util.h"
+#include "fs-util.h"
+#include "log.h"
 #include "string-util.h"
 #include "util.h"
 
@@ -35,20 +37,29 @@ int main(int argc, char** argv) {
         const char *p = argv[1] ?: "/tmp";
         char *pattern = strjoina(p, "/systemd-test-XXXXXX");
         _cleanup_close_ int fd, fd2;
-        _cleanup_free_ char *cmd, *cmd2;
+        _cleanup_free_ char *cmd, *cmd2, *ans, *ans2;
+
+        log_set_max_level(LOG_DEBUG);
+        log_parse_environment();
 
         fd = open_tmpfile(p, O_RDWR|O_CLOEXEC);
         assert_se(fd >= 0);
 
         assert_se(asprintf(&cmd, "ls -l /proc/"PID_FMT"/fd/%d", getpid(), fd) > 0);
-        system(cmd);
+        (void) system(cmd);
+        assert_se(readlink_malloc(cmd + 6, &ans) >= 0);
+        log_debug("link1: %s", ans);
+        assert_se(endswith(ans, " (deleted)"));
 
         fd2 = mkostemp_safe(pattern, O_RDWR|O_CLOEXEC);
         assert_se(fd >= 0);
         assert_se(unlink(pattern) == 0);
 
         assert_se(asprintf(&cmd2, "ls -l /proc/"PID_FMT"/fd/%d", getpid(), fd2) > 0);
-        system(cmd2);
+        (void) system(cmd2);
+        assert_se(readlink_malloc(cmd2 + 6, &ans2) >= 0);
+        log_debug("link2: %s", ans2);
+        assert_se(endswith(ans2, " (deleted)"));
 
         return 0;
 }