From 8bd08ebb7110883eb15068077dd24dc045f3314f Mon Sep 17 00:00:00 2001 From: PatR Date: Mon, 12 Apr 2021 13:25:52 -0700 Subject: [PATCH] level teleporters vs Ft.Ludios From newsgroup discussion where slash'em changes have revealed a latent nethack bug: prevent placing level teleporters in single- level branches. The Knox level doesn't have any level teleporters (or random traps) but wizard mode wishing could create them there. They wouldn't do anything because the only possible destination would be the same level. Pushing a boulder onto one used to trigger an infinite loop (and still does in slash'em, which has other single-level branches besides Ft.Ludios) trying to relocate it. Boulder pushing was changed 15 years ago to prevent the infinite loop and to avoid giving "the boulder disappears" message when a level teleporter failed, but rolling boulder traversal lacked that same change--it wasn't vulnerable to looping but could give an inaccurate message claiming that the boulder disappeared when it actually didn't. Fixing this is a bit late; rolling boulder trap creation was recently changed to not choose a path that rolls over teleportation or level tele traps any more. --- doc/fixes37.0 | 3 +++ include/extern.h | 1 + src/dungeon.c | 11 +++++++++++ src/hack.c | 22 +++++++++++----------- src/mklev.c | 3 ++- src/teleport.c | 4 ++-- src/trap.c | 36 +++++++++++++++++++++++------------- 7 files changed, 53 insertions(+), 27 deletions(-) diff --git a/doc/fixes37.0 b/doc/fixes37.0 index 1495a7ae0..97365e891 100644 --- a/doc/fixes37.0 +++ b/doc/fixes37.0 @@ -449,6 +449,9 @@ turn off input autocompletion for '#twoweapon' since simple 'X' invokes it; likewise for #wizdetect (^E), #wizgenesis (^G), #wizidentify (^I), #wizlevelport (^V), #wizmap (^F), and #wizwish (^W); probably ought to do so for #overview (^O) too but that one still autocompletes +if a branch has only one level (Fort Ludios), prevent creation of any level + teleporters there (level definition doesn't have any but wizard mode + wishing could attempt to place one) Fixes to 3.7.0-x Problems that Were Exposed Via git Repository diff --git a/include/extern.h b/include/extern.h index a42769579..3da9d738e 100644 --- a/include/extern.h +++ b/include/extern.h @@ -618,6 +618,7 @@ extern boolean On_W_tower_level(d_level *); extern boolean In_W_tower(int, int, d_level *); extern void find_hell(d_level *); extern void goto_hell(boolean, boolean); +extern boolean single_level_branch(d_level *); extern void assign_level(d_level *, d_level *); extern void assign_rnd_level(d_level *, d_level *, int); extern unsigned int induced_align(int); diff --git a/src/dungeon.c b/src/dungeon.c index 427ec44fa..5f851a0a7 100644 --- a/src/dungeon.c +++ b/src/dungeon.c @@ -1848,6 +1848,17 @@ goto_hell(boolean at_stairs, boolean falling) goto_level(&lev, at_stairs, falling, FALSE); } +/* is 'lev' the only level in its branch? affects level teleporters */ +boolean +single_level_branch(d_level *lev) +{ + /* + * TODO: this should be generalized instead of assuming that + * Fort Ludios is the only single level branch in the dungeon. + */ + return Is_knox(lev); +} + /* equivalent to dest = source */ void assign_level(d_level *dest, d_level *src) diff --git a/src/hack.c b/src/hack.c index 5422e4a03..435ad9b3a 100644 --- a/src/hack.c +++ b/src/hack.c @@ -178,6 +178,9 @@ moverock(void) } if (ttmp) { + int newlev = 0; /* lint suppression */ + d_level dest; + /* if a trap operates on the boulder, don't attempt to move any others at this location; return -1 if another boulder is in hero's way, or 0 if he @@ -236,16 +239,14 @@ moverock(void) newsym(rx, ry); return sobj_at(BOULDER, sx, sy) ? -1 : 0; case LEVEL_TELEP: - case TELEP_TRAP: { - int newlev = 0; /* lint suppression */ - d_level dest; - - if (ttmp->ttyp == LEVEL_TELEP) { - newlev = random_teleport_level(); - if (newlev == depth(&u.uz) || In_endgame(&u.uz)) - /* trap didn't work; skip "disappears" message */ - goto dopush; - } + /* 20% chance of picking current level; 100% chance for + that if in single-level branch (Knox) or in endgame */ + newlev = random_teleport_level(); + /* if trap doesn't work, skip "disappears" message */ + if (newlev == depth(&u.uz)) + goto dopush; + /*FALLTHRU*/ + case TELEP_TRAP: if (u.usteed) pline("%s pushes %s and suddenly it disappears!", upstart(y_monnam(u.usteed)), the(xname(otmp))); @@ -264,7 +265,6 @@ moverock(void) } seetrap(ttmp); return sobj_at(BOULDER, sx, sy) ? -1 : 0; - } default: break; /* boulder not affected by this trap */ } diff --git a/src/mklev.c b/src/mklev.c index dc606f7ad..53273bc14 100644 --- a/src/mklev.c +++ b/src/mklev.c @@ -1377,7 +1377,8 @@ mktrap(int num, int mazeflag, struct mkroom *croom, coord *tm) kind = NO_TRAP; break; case LEVEL_TELEP: - if (lvl < 5 || g.level.flags.noteleport) + if (lvl < 5 || g.level.flags.noteleport + || single_level_branch(&u.uz)) kind = NO_TRAP; break; case SPIKED_PIT: diff --git a/src/teleport.c b/src/teleport.c index 1e901cb96..f79ddd147 100644 --- a/src/teleport.c +++ b/src/teleport.c @@ -892,7 +892,7 @@ level_tele(void) /* if in Knox and the requested level > 0, stay put. * we let negative values requests fall into the "heaven" loop. */ - if (Is_knox(&u.uz) && newlev > 0 && !force_dest) { + if (single_level_branch(&u.uz) && newlev > 0 && !force_dest) { You1(shudder_for_moment); return; } @@ -1532,7 +1532,7 @@ random_teleport_level(void) int nlev, max_depth, min_depth, cur_depth = (int) depth(&u.uz); /* [the endgame case can only occur in wizard mode] */ - if (!rn2(5) || Is_knox(&u.uz) || In_endgame(&u.uz)) + if (!rn2(5) || single_level_branch(&u.uz) || In_endgame(&u.uz)) return cur_depth; /* What I really want to do is as follows: diff --git a/src/trap.c b/src/trap.c index 1a7917b57..2b6f060e0 100644 --- a/src/trap.c +++ b/src/trap.c @@ -352,10 +352,12 @@ maketrap(int x, int y, int typ) || (u.utraptype == TT_LAVA && !is_lava(x, y)))) reset_utrap(FALSE); /* old remain valid */ - } else if (IS_FURNITURE(lev->typ) - && (!IS_GRAVE(lev->typ) || (typ != PIT && typ != HOLE))) { + } else if ((IS_FURNITURE(lev->typ) + && (!IS_GRAVE(lev->typ) || (typ != PIT && typ != HOLE))) + || (typ == LEVEL_TELEP && single_level_branch(&u.uz))) { /* no trap on top of furniture (caller usually screens the - location to inhibit this, but wizard mode wishing doesn't) */ + location to inhibit this, but wizard mode wishing doesn't) + and no level teleporter in branch with only one level */ return (struct trap *) 0; } else { oldplace = FALSE; @@ -2778,6 +2780,9 @@ launch_obj( } } if ((t = t_at(g.bhitpos.x, g.bhitpos.y)) != 0 && otyp == BOULDER) { + int newlev = 0; + d_level dest; + switch (t->ttyp) { case LANDMINE: if (rn2(10) > 2) { @@ -2801,20 +2806,22 @@ launch_obj( } break; case LEVEL_TELEP: + /* 20% chance of picking current level; 100% chance for + that if in single-level branch (Knox) or in endgame */ + newlev = random_teleport_level(); + /* if trap doesn't work, skip "disappears" message */ + if (newlev == depth(&u.uz)) + break; + /*FALLTHRU*/ case TELEP_TRAP: if (cansee(g.bhitpos.x, g.bhitpos.y)) pline("Suddenly the rolling boulder disappears!"); - else + else if (!Deaf) You_hear("a rumbling stop abruptly."); singleobj->otrapped = 0; - if (t->ttyp == TELEP_TRAP) + if (t->ttyp == TELEP_TRAP) { (void) rloco(singleobj); - else { - int newlev = random_teleport_level(); - d_level dest; - - if (newlev == depth(&u.uz) || In_endgame(&u.uz)) - continue; + } else { add_to_migration(singleobj); get_level(&dest, newlev); singleobj->ox = dest.dnum; @@ -2838,9 +2845,12 @@ launch_obj( } dist = -1; /* stop rolling immediately */ break; - } - if (used_up || dist == -1) + default: break; + } + + if (used_up || dist == -1) + break; /* from 'while' loop */ } if (flooreffects(singleobj, g.bhitpos.x, g.bhitpos.y, "fall")) { used_up = TRUE;