Dynamic priority scheme between TTY and FIFO.

Whenever a character from the TTY are processed, the work bout
size (max number of lines processed without polling TTY
or time-of-day) is cut in half, so as the user types, the
UI quickly becomes more responsive. When TTY activity
ceases, the work bout successively grows in size again
toward the maximum value to favor more efficient reading.

1 files changed, 8 insertions, 2 deletions

diff --git a/pw.c b/pw.c
index f6c79fc..e3a2b0a 100644
--- a/pw.c
+++ b/pw.c
@@ -653,7 +653,7 @@ int main(int argc, char **argv)
 
   for (unsigned stat = stat_dirty, hpos = 0,
                 kbd_state = kbd_cmd, kbd_prev = kbd_cmd, lasttime = ~0U,
-                work = 1000, histpos = 0;
+                workbout = 1024, work = workbout, histpos = 0;
        kbd_state != kbd_exit ;)
   {
     int force = 0, nfds = 2, pollms = poll_interval;
@@ -759,7 +759,7 @@ int main(int argc, char **argv)
     if (pollms == 0 && !force && work-- > 0)
       continue;
 
-    work = 1000;
+    work = workbout;
 
     if (!force)
     {
@@ -794,10 +794,14 @@ int main(int argc, char **argv)
           drawstatus(columns, stat, curcmd);
         }
       }
+      work = workbout += workbout / 4;
     } else {
       if ((pe[0].revents)) {
         int ch = getc(tty);
 
+        if (workbout > 16)
+          work = workbout /= 2;
+
         if (ch == ctrl('z')) {
           ttyset(ttyfd, &tty_saved);
           kill(0, SIGTSTP);
@@ -1049,6 +1053,8 @@ int main(int argc, char **argv)
           clrline();
           drawstatus(columns, stat, curcmd);
         }
+      } else {
+        work = workbout += workbout / 4;
       }
     }
   }