From f3bf6b542e7e16b4ad99becc777e01b3bd5040dd Mon Sep 17 00:00:00 2001
From: helixhorned <helixhorned@1a8010ca-5511-0410-912e-c29ae57300e0>
Date: Sun, 23 Jan 2011 15:30:28 +0000
Subject: [PATCH] With the help of Coccinelle, eliminate a few sector[-1]
 accesses and calculations of &sector[-1] (bound checking code not committed).

git-svn-id: https://svn.eduke32.com/eduke32@1780 1a8010ca-5511-0410-912e-c29ae57300e0
---
 polymer/eduke32/build/src/engine.c   | 11 ++++++++++-
 polymer/eduke32/build/src/polymost.c |  3 ++-
 polymer/eduke32/source/astub.c       |  2 +-
 3 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/polymer/eduke32/build/src/engine.c b/polymer/eduke32/build/src/engine.c
index 3863f4072..deee5ba51 100644
--- a/polymer/eduke32/build/src/engine.c
+++ b/polymer/eduke32/build/src/engine.c
@@ -3110,7 +3110,8 @@ static void drawalls(int32_t bunch)
         }
 
         wallnum = thewall[z]; wal = &wall[wallnum];
-        nextsectnum = wal->nextsector; nextsec = &sector[nextsectnum];
+        nextsectnum = wal->nextsector;
+        nextsec = nextsectnum>=0 ? &sector[nextsectnum] : NULL;
 
         gotswall = 0;
 
@@ -6490,6 +6491,14 @@ void drawrooms(int32_t daposx, int32_t daposy, int32_t daposz,
         i = globalcursectnum;
         updatesector(globalposx,globalposy,&globalcursectnum);
         if (globalcursectnum < 0) globalcursectnum = i;
+
+        // PK 20110123: I'm not sure what the line above is supposed to do, but 'i'
+        //              *can* be negative, so let's just quit here in that case...
+        if (globalcursectnum<0)
+        {
+            enddrawing();
+            return;
+        }
     }
 
     globparaceilclip = 1;
diff --git a/polymer/eduke32/build/src/polymost.c b/polymer/eduke32/build/src/polymost.c
index 6015b3b99..729cf4bad 100644
--- a/polymer/eduke32/build/src/polymost.c
+++ b/polymer/eduke32/build/src/polymost.c
@@ -3087,7 +3087,8 @@ static void polymost_drawalls(int32_t bunch)
     for (z=bunchfirst[bunch]; z>=0; z=p2[z])
     {
         wallnum = thewall[z]; wal = &wall[wallnum]; wal2 = &wall[wal->point2];
-        nextsectnum = wal->nextsector; nextsec = &sector[nextsectnum];
+        nextsectnum = wal->nextsector;
+        nextsec = nextsectnum>=0 ? &sector[nextsectnum] : NULL;
 
         //Offset&Rotate 3D coordinates to screen 3D space
         x = wal->x-globalposx; y = wal->y-globalposy;
diff --git a/polymer/eduke32/source/astub.c b/polymer/eduke32/source/astub.c
index e4ba8fe97..316faa10e 100644
--- a/polymer/eduke32/source/astub.c
+++ b/polymer/eduke32/source/astub.c
@@ -5507,7 +5507,7 @@ static void Keys3d(void)
     }
     */
 
-    if (sector[cursectnum].lotag==2)
+    if (cursectnum>=0 && sector[cursectnum].lotag==2)
     {
         if (sector[cursectnum].ceilingpicnum==FLOORSLIME)
             SetSLIMEPalette();