top: add visual clue when focus toggle ('F') is activenewlib

When in forest view mode, that focus toggle ('F') is a
useful tool occasionally. But, if a focused parent has
enough cloned siblings to exceed screen rows, it could
be hard to remember that such a toggle remains active.

So, this patch will provide a subtle visual clue added
to the leftmost position in the COMMAND column. Now if
the focus toggle was active, regardless of total tasks
affected, the users will always know when it's active.

Reference(s):
. -7/24/21, introduced new focus toggle
commit 3e922e671daf09ae60ee211b5c0ef94996ee573d
. 09/23/21, ensure focused tasks stay focused
commit 69978e365043f27305e487709474947bb377084d

Signed-off-by: Jim Warner <james.warner@comcast.net>

2 files changed, 10 insertions, 1 deletions

diff --git a/top/top.c b/top/top.c
index f064c29..3aae009 100644
--- a/top/top.c
+++ b/top/top.c
@@ -4685,8 +4685,16 @@ static inline const char *forest_display (const WIN_t *q, int idx) {
 #endif
       return buf;
    }
-   if (level > 100) snprintf(buf, sizeof(buf), "%400s%s", " +  ", which);
+   if (level > 100) {
+      snprintf(buf, sizeof(buf), "%400s%s", " +  ", which);
+      return buf;
+   }
+#ifndef FOCUS_VIZOFF
+   if (q->focus_pid) snprintf(buf, sizeof(buf), "|%*s%s", ((4 * level) - 1), "`- ", which);
    else snprintf(buf, sizeof(buf), "%*s%s", (4 * level), " `- ", which);
+#else
+   snprintf(buf, sizeof(buf), "%*s%s", (4 * level), " `- ", which);
+#endif
    return buf;
  #undef rSv
  #undef rSv_Lvl
diff --git a/top/top.h b/top/top.h
index 3e28afe..5279772 100644
--- a/top/top.h
+++ b/top/top.h
@@ -31,6 +31,7 @@
 //#define EQUCOLHDRYES            /* yes, equalize the column header lengths */
 //#define FOCUS_HARD_Y            /* 'F' will avoid topmost task distortions */
 //#define FOCUS_TREE_X            /* 'F' resets forest view indentation to 0 */
+//#define FOCUS_VIZOFF            /* 'F' doesn't provide the visual clue '|' */
 //#define GETOPTFIX_NO            /* do not address getopt_long deficiencies */
 //#define INSP_JUSTNOT            /* do not smooth unprintable right margins */
 //#define INSP_OFFDEMO            /* disable demo screens, issue msg instead */