poly'd hero movement

Noticed while fixing the 'monster intrinsics from worn gear' bug(s):
set_uasmon() calls set_mon_data(&youmonst,...) which updates movement
when the monster polymorphs into something slower, then it did the
same thing to youmonst.movement itself, hitting the hero with a double
dose of reduction for any movement points not yet spent on current
turn.  Remove the set_uasmon() side of that, and change set_mon_data()
side to add a redundant non-zero test to prevent static analysis from
warning that it might be dividing by 0.

diff --git a/src/mondata.c b/src/mondata.c
index aeb56d56bc1c8ae9f8702b7a6e0e1d6016554db7..fae34e8b7d99fc7769722dfcb03fd70b43b229fe 100644 (file)
--- a/src/mondata.c
+++ b/src/mondata.c
@@ -1,4 +1,4 @@
-/* NetHack 3.6 mondata.c       $NHDT-Date: 1550524563 2019/02/18 21:16:03 $  $NHDT-Branch: NetHack-3.6.2-beta01 $:$NHDT-Revision: 1.71 $ */
+/* NetHack 3.6 mondata.c       $NHDT-Date: 1550525093 2019/02/18 21:24:53 $  $NHDT-Branch: NetHack-3.6.2-beta01 $:$NHDT-Revision: 1.72 $ */
 /* Copyright (c) Stichting Mathematisch Centrum, Amsterdam, 1985. */
 /*-Copyright (c) Robert Patrick Rankin, 2011. */
 /* NetHack may be freely redistributed.  See license for details. */
@@ -19,13 +19,21 @@ struct permonst *ptr;
     mon->data = ptr;
     mon->mnum = (short) monsndx(ptr);
 
-    if (mon->movement) { /* same adjustment as poly'd hero undergoes */
+    if (mon->movement) { /* used to adjust poly'd hero as well as monsters */
         new_speed = ptr->mmove;
         /* prorate unused movement if new form is slower so that
            it doesn't get extra moves leftover from previous form;
            if new form is faster, leave unused movement as is */
-        if (new_speed < old_speed)
-            mon->movement = new_speed * mon->movement / old_speed;
+        if (new_speed < old_speed) {
+            /*
+             * Some static analysis warns that this might divide by 0
+               mon->movement = new_speed * mon->movement / old_speed;
+             * so add a redundant test to suppress that.
+             */
+            mon->movement *= new_speed;
+            if (old_speed > 0) /* old > new and new >= 0, so always True */
+                mon->movement /= old_speed;
+        }
     }
     return;
 }

diff --git a/src/polyself.c b/src/polyself.c
index 59a21397fa4a58b05f5fdcccff06f86b16df5641..b9e6fa81b5b1915522438526b72c2de3bf77d910 100644 (file)
--- a/src/polyself.c
+++ b/src/polyself.c
@@ -1,4 +1,4 @@
-/* NetHack 3.6 polyself.c      $NHDT-Date: 1550524564 2019/02/18 21:16:04 $  $NHDT-Branch: NetHack-3.6.2-beta01 $:$NHDT-Revision: 1.127 $ */
+/* NetHack 3.6 polyself.c      $NHDT-Date: 1550525094 2019/02/18 21:24:54 $  $NHDT-Branch: NetHack-3.6.2-beta01 $:$NHDT-Revision: 1.128 $ */
 /*      Copyright (C) 1987, 1988, 1989 by Ken Arromdee */
 /* NetHack may be freely redistributed.  See license for details. */
 
@@ -41,7 +41,6 @@ void
 set_uasmon()
 {
     struct permonst *mdat = &mons[u.umonnum];
-    int new_speed, old_speed = youmonst.data ? youmonst.data->mmove : 0;
 
     set_mon_data(&youmonst, mdat);
 
@@ -101,15 +100,6 @@ set_uasmon()
     float_vs_flight(); /* maybe toggle (BFlying & I_SPECIAL) */
     polysense();
 
-    if (youmonst.movement) {
-        new_speed = mdat->mmove;
-        /* prorate unused movement if new form is slower so that
-           it doesn't get extra moves leftover from previous form;
-           if new form is faster, leave unused movement as is */
-        if (new_speed < old_speed)
-            youmonst.movement = new_speed * youmonst.movement / old_speed;
-    }
-
 #ifdef STATUS_HILITES
     status_initialize(REASSESS_ONLY);
 #endif