atc - Fix bug related to delayed command and altitude change

When playing atc, if a plane has a delayed turn command, and you issue
an altitude command that would send the plane to the same altitude to
which it is already going, the delay is disabled and the plane turns
immediately.

Fix is from OpenBSD (PR 3448).

Discussed-with: swildner@
Provided-by: 26c3

diff --git a/games/atc/input.c b/games/atc/input.c
index dbe8574..18cd419 100644 (file)
--- a/games/atc/input.c
+++ b/games/atc/input.c
@@ -525,6 +525,8 @@ setalt(int c)
 {
        if ((p.altitude == c - '0') && (p.new_altitude == p.altitude))
                return ("Already at that altitude");
+       if (p.new_altitude == c - '0')
+               return ("Already going to that altitude");
        p.new_altitude = c - '0';
        return (NULL);
 }
@@ -532,24 +534,30 @@ setalt(int c)
 static const char *
 setrelalt(int c)
 {
+       int new_altitude;
+
        if (c == 0)
                return ("altitude not changed");
 
        switch (dir) {
        case D_UP:
-               p.new_altitude = p.altitude + c - '0';
+               new_altitude = p.altitude + c - '0';
                break;
        case D_DOWN:
-               p.new_altitude = p.altitude - (c - '0');
+               new_altitude = p.altitude - (c - '0');
                break;
        default:
                return ("Unknown case in setrelalt!  Get help!");
                break;
        }
-       if (p.new_altitude < 0)
+       if (new_altitude < 0)
                return ("Altitude would be too low");
-       else if (p.new_altitude > 9)
+       else if (new_altitude > 9)
                return ("Altitude would be too high");
+       else if (new_altitude == p.new_altitude)
+               return ("Already going to that altitude");
+
+       p.new_altitude = new_altitude;
        return (NULL);
 }