From 6b750cb551f3d90692802a9a800d1dcb45e704be Mon Sep 17 00:00:00 2001
From: PatR <rankin@nethack.org>
Date: Sat, 25 May 2024 17:48:17 -0700
Subject: [PATCH] hit points sanity checks

---
 src/mon.c     | 17 +++++++----------
 src/potion.c  |  2 +-
 src/wizcmds.c | 18 ++++++++++++++++++
 3 files changed, 26 insertions(+), 11 deletions(-)

diff --git a/src/mon.c b/src/mon.c
index b028308bc..f4666b151 100644
--- a/src/mon.c
+++ b/src/mon.c
@@ -75,23 +75,20 @@ sanity_check_single_mon(
                        mtmp->mnum, mndx, msg);
             mtmp->mnum = mndx;
         }
-#if 0   /*
-         * Gremlins don't obey the (mhpmax >= m_lev) rule so disable
-         * this check, at least for the time being.  We could skip it
-         * when the cloned flag is set, but the original gremlin would
-         * still be an issue.
-         */
         /* check before DEADMONSTER() because dead monsters should still
            have sane mhpmax */
         if (mtmp->mhpmax < 1
+            /* Gremlins don't obey the (mhpmax >= m_lev) rule so disable
+             * this check, at least for the time being.  We could skip it
+             * when the cloned flag is set, but the original gremlin would
+             * still be an issue.
             || mtmp->mhpmax < (int) mtmp->m_lev
+             */
             || mtmp->mhp > mtmp->mhpmax)
-            impossible(
-                     "%s: level %d monster #%u [%s] has %d cur HP, %d max HP",
-                       msg, (int) mtmp->m_lev,
+            impossible("%s: level %d %s #%u [%s] has %d cur HP, %d max HP",
+                       msg, (int) mtmp->m_lev, mptr->pmnames[NEUTRAL],
                        mtmp->m_id, fmt_ptr((genericptr_t) mtmp),
                        mtmp->mhp, mtmp->mhpmax);
-#endif
         if (DEADMONSTER(mtmp)) {
 #if 0
             /* bad if not fmon list or if not vault guard */
diff --git a/src/potion.c b/src/potion.c
index c0c4df819..d97f274a9 100644
--- a/src/potion.c
+++ b/src/potion.c
@@ -2832,7 +2832,7 @@ split_mon(
         mtmp2 = (u.mh > 1) ? cloneu() : (struct monst *) 0;
         if (mtmp2) {
             /* mtmp2 has been created with mhpmax = u.mhmax, mhp = u.mh / 2,
-               and u.mh -= mtmp2->mhpmax; these reductions for both max hp
+               and u.mh -= mtmp2->mhp; these reductions for both max hp
                can't make either of them exceed corresponding current hp */
             mtmp2->mhpmax = u.mhmax / 2;
             u.mhmax -= mtmp2->mhpmax;
diff --git a/src/wizcmds.c b/src/wizcmds.c
index cf8fc75e9..f4f3006f2 100644
--- a/src/wizcmds.c
+++ b/src/wizcmds.c
@@ -1401,6 +1401,24 @@ you_sanity_check(void)
         if (u.ustuck != mtmp)
             impossible("sanity_check: you over monster");
     }
+    /* [should we also check for (u.uhp < 1), (Upolyd && u.mh < 1),
+       and (u.uen < 0) here?] */
+    if (u.uhp > u.uhpmax) {
+        impossible("current hero health (%d) better than maximum? (%d)",
+                   u.uhp, u.uhpmax);
+        u.uhp = u.uhpmax;
+    }
+    if (Upolyd && u.mh > u.mhmax) {
+        impossible(
+              "current hero health as monster (%d) better than maximum? (%d)",
+                   u.mh, u.mhmax);
+        u.mh = u.mhmax;
+    }
+    if (u.uen > u.uenmax) {
+        impossible("current hero energy (%d) better than maximum? (%d)",
+                   u.uen, u.uenmax);
+        u.uen = u.uenmax;
+    }
 
     check_wornmask_slots();
     (void) check_invent_gold("invent");