journal: expose and make use of cutoff times of journal

This helps explaining when the log output of "systemctl status" is
incomplete because the logs got rotated since the service was started.

1 files changed, 20 insertions, 0 deletions

diff --git a/src/journal/journalctl.c b/src/journal/journalctl.c
index 9d4403267e..e9d918a733 100644
--- a/src/journal/journalctl.c
+++ b/src/journal/journalctl.c
@@ -281,6 +281,26 @@ int main(int argc, char *argv[]) {
                 goto finish;
         }
 
+        if (!arg_quiet) {
+                usec_t start, end;
+                char start_buf[FORMAT_TIMESTAMP_MAX], end_buf[FORMAT_TIMESTAMP_MAX];
+
+                r = sd_journal_get_cutoff_realtime_usec(j, &start, &end);
+                if (r < 0) {
+                        log_error("Failed to get cutoff: %s", strerror(-r));
+                        goto finish;
+                }
+
+                if (r > 0) {
+                        if (arg_follow)
+                                printf("Logs begin at %s.\n", format_timestamp(start_buf, sizeof(start_buf), start));
+                        else
+                                printf("Logs begin at %s, end at %s.\n",
+                                       format_timestamp(start_buf, sizeof(start_buf), start),
+                                       format_timestamp(end_buf, sizeof(end_buf), end));
+                }
+        }
+
         if (arg_lines >= 0) {
                 r = sd_journal_seek_tail(j);
                 if (r < 0) {