[lss] handle invalid row number

.github/workflows/bins.yml

@@ -67,6 +67,7 @@ jobs:
 
   build-arm:
     runs-on: ubuntu-latest
+    if: ${{ inputs.lnav_version_number != '' }}
     strategy:
       matrix:
         include:

src/logfile_sub_source.hh

@@ -479,7 +479,7 @@ public:
 
     nonstd::optional<struct timeval> time_for_row(vis_line_t row)
     {
-        if (row < (ssize_t) this->text_line_count()) {
+        if (row >= 0_vl && row < (ssize_t) this->text_line_count()) {
             return this->find_line(this->at(row))->get_timeval();
         }
         return nonstd::nullopt;

src/textview_curses.cc

@@ -832,7 +832,9 @@ text_time_translator::data_reloaded(textview_curses* tc)
     if (tc->get_inner_height() == 0) {
         return;
     }
-    if (tc->get_selection() > tc->get_inner_height()) {
+    if (tc->get_selection() < 0_vl
+        || tc->get_selection() > tc->get_inner_height())
+    {
         if (this->ttt_top_time.tv_sec != 0) {
             this->row_for_time(this->ttt_top_time) |
                 [tc](auto new_top) { tc->set_selection(new_top); };