Fix a bug in monster summoning that was causing crashes, for example

when attempting to cast Shadow Creatures in a bazaar (which is bound to
fail, anyway). I guess it would have also caused crashes anywhere else
where the level was devoid of monsters and creating one failed - for
whatever reason. I don't actually know how likely that combination is.


git-svn-id: https://crawl-ref.svn.sourceforge.net/svnroot/crawl-ref/trunk@6151 c06c8d41-db1a-0410-9941-cceddc491573

4 files changed, 28 insertions, 27 deletions

diff --git a/crawl-ref/source/monplace.cc b/crawl-ref/source/monplace.cc
index 7bbe489f2d..40ab8e00a8 100644
--- a/crawl-ref/source/monplace.cc
+++ b/crawl-ref/source/monplace.cc
@@ -261,12 +261,14 @@ void spawn_random_monsters()
     // No monsters in the Labyrinth, or the Ecumenical Temple, or in Bazaars.
 }
 
-monster_type pick_random_monster(const level_id &place,
-                                 int power,
+monster_type pick_random_monster(const level_id &place, int power,
                                  int &lev_mons)
 {
-    if (place.level_type == LEVEL_LABYRINTH)
+    if (place.level_type == LEVEL_LABYRINTH
+        || place.level_type == LEVEL_PORTAL_VAULT)
+    {
         return (MONS_PROGRAM_BUG);
+    }
 
     monster_type mon_type = MONS_PROGRAM_BUG;
 
@@ -425,11 +427,12 @@ static monster_type _resolve_monster_type(monster_type mon_type,
     if (mon_type == RANDOM_MONSTER)
     {
         level_id place = level_id::current();
-        // respect destination level for staircases
+
+        // Respect destination level for staircases.
         if (proximity == PROX_NEAR_STAIRS)
         {
             int tries = 0;
-            int pval = 0;
+            int pval  = 0;
             while (++tries <= 320)
             {
                 pos = random_in_bounds();
@@ -469,7 +472,7 @@ static monster_type _resolve_monster_type(monster_type mon_type,
             }
             else
             {
-                if ( *stair_type == DCHAR_STAIRS_DOWN ) // deeper level
+                if (*stair_type == DCHAR_STAIRS_DOWN) // deeper level
                     ++*lev_mons;
                 else if (*stair_type == DCHAR_STAIRS_UP) // higher level
                 {
@@ -547,7 +550,7 @@ int place_monster(mgen_data mg, bool force_pos)
                                    &stair_type, &mg.power);
 
     if (mg.cls == MONS_PROGRAM_BUG)
-        return (false);
+        return (-1);
 
     // (3) Decide on banding (good lord!)
     band_size = 1;
@@ -1862,8 +1865,6 @@ int mons_place( mgen_data mg )
     if (mg.cls == RANDOM_MONSTER || mg.level_type == LEVEL_PANDEMONIUM)
         mg.flags |= MG_PERMIT_BANDS;
 
-    int mid = -1;
-
     // Translate level_type.
     switch (mg.level_type)
     {
@@ -1879,7 +1880,7 @@ int mons_place( mgen_data mg )
             break;
     }
 
-    mid = place_monster(mg);
+    int mid = place_monster(mg);
     if (mid == -1)
         return (-1);
 
@@ -2093,7 +2094,7 @@ bool player_angers_monster(monsters *mon)
     return (false);
 }
 
-int create_monster( mgen_data mg )
+int create_monster( mgen_data mg, bool fail_msg )
 {
     int summd = -1;
     int type = (mons_class_is_zombified(mg.cls) ? mg.base_type
@@ -2113,7 +2114,7 @@ int create_monster( mgen_data mg )
 
     // Determine whether creating a monster is successful (summd != -1) {dlb}:
     // then handle the outcome. {dlb}:
-    if (summd == -1 && see_grid( mg.pos ))
+    if (fail_msg && summd == -1 && see_grid( mg.pos ))
         mpr("You see a puff of smoke.");
 
     // The return value is either -1 (failure of some sort)
diff --git a/crawl-ref/source/monplace.h b/crawl-ref/source/monplace.h
index bbba9f3c3f..ab03196433 100644
--- a/crawl-ref/source/monplace.h
+++ b/crawl-ref/source/monplace.h
@@ -21,7 +21,7 @@
 enum band_type
 {
     BAND_NO_BAND                = 0,
-    BAND_KOBOLDS                = 1,
+    BAND_KOBOLDS,
     BAND_ORCS,
     BAND_ORC_WARRIOR,
     BAND_ORC_KNIGHT,
@@ -35,6 +35,7 @@ enum band_type
     BAND_HELL_KNIGHTS,
     BAND_ORC_HIGH_PRIEST,
     BAND_GNOLLS,                // 14
+    // 15
     BAND_BUMBLEBEES             = 16,
     BAND_CENTAURS,
     BAND_YAKTAURS,
@@ -63,9 +64,9 @@ enum band_type
     BAND_GIANT_MOSQUITOES,
     BAND_BOGGARTS,
     BAND_BLINK_FROGS,
-    BAND_SKELETAL_WARRIORS,     // 44
+    BAND_SKELETAL_WARRIORS,
     BAND_DRACONIAN,             // 45
-    BAND_PANDEMONIUM_DEMON,
+    BAND_PANDEMONIUM_DEMON,     // 46
     NUM_BANDS                   // always last
 };
 
@@ -234,7 +235,7 @@ struct mgen_data
  * used for summons and other monsters that want to appear near a given
  * position like a summon.
  * *********************************************************************** */
-int create_monster( mgen_data mg );
+int create_monster( mgen_data mg, bool fail_msg = true );
 
 /* ***********************************************************************
  * Primary function to create monsters. See mgen_data for details on monster
diff --git a/crawl-ref/source/newgame.cc b/crawl-ref/source/newgame.cc
index 11a99c47b4..e941a984c3 100644
--- a/crawl-ref/source/newgame.cc
+++ b/crawl-ref/source/newgame.cc
@@ -1917,6 +1917,9 @@ static bool _choose_book( item_def& book, int firstbook, int numbooks )
     switch (you.species)
     {
     case SP_OGRE:
+        // Ogres are, of course, really bad at Fire and Ice, so it's usually
+        // restricted, but if the summoning book comes into play unrestrict
+        // those two because ogres are even *worse* at Summonings.
         if (numbooks < 3)
             book_restrictions[0] = CC_RESTRICTED;
         // else fall-through
diff --git a/crawl-ref/source/spells3.cc b/crawl-ref/source/spells3.cc
index d3b5ae799a..524cf1f790 100644
--- a/crawl-ref/source/spells3.cc
+++ b/crawl-ref/source/spells3.cc
@@ -563,26 +563,22 @@ bool cast_summon_greater_demon(int pow, god_type god)
 
 bool cast_shadow_creatures(god_type god)
 {
-    bool success = false;
-
     mpr("Wisps of shadow whirl around you...");
 
     const int monster =
         create_monster(
             mgen_data(RANDOM_MONSTER, BEH_FRIENDLY, 2,
                       you.pos(), you.pet_target,
-                      MG_FORCE_BEH, god));
+                      MG_FORCE_BEH, god), false);
 
-    if (monster != -1)
+    if (monster == -1)
     {
-        success = true;
-
-        player_angers_monster(&menv[monster]);
+        mpr("The shadows disperse without effect.");
+        return (false);
     }
-    else
-        canned_msg(MSG_NOTHING_HAPPENS);
 
-    return (success);
+    player_angers_monster(&menv[monster]);
+    return (true);
 }
 
 bool cast_summon_horrible_things(int pow, god_type god)
@@ -640,7 +636,7 @@ bool cast_summon_horrible_things(int pow, god_type god)
 
     if (count > 0)
     {
-        mprf("Some Thing%s answered your call!",
+        mprf("Some thing%s answered your call!",
              count > 1 ? "s" : "");
         return (true);
     }