ref: a3ab0a6910f55c6f45a3f4eaf48b4a99c4e16e22
parent: df49602893b3bbe625dfc757949b93ea6b7339e0
author: Simon Howard <[email protected]>
date: Sat Oct 17 15:29:46 EDT 2009
Import donut overrun emulation code from PrBoom+ (Thanks entryway). Subversion-branch: /trunk/chocolate-doom Subversion-revision: 1720
--- a/src/m_misc.c
+++ b/src/m_misc.c
@@ -198,3 +198,11 @@
return result;
}
+boolean M_StrToInt(const char *str, int *result)
+{+ return sscanf(str, " 0x%x", result) == 1
+ || sscanf(str, " 0X%x", result) == 1
+ || sscanf(str, " 0%o", result) == 1
+ || sscanf(str, " %d", result) == 1;
+}
+
--- a/src/m_misc.h
+++ b/src/m_misc.h
@@ -39,6 +39,7 @@
char *M_TempFile(char *s);
boolean M_FileExists(char *file);
long M_FileLength(FILE *handle);
+boolean M_StrToInt(const char *str, int *result);
#endif
--- a/src/p_spec.c
+++ b/src/p_spec.c
@@ -38,6 +38,7 @@
#include "i_system.h"
#include "z_zone.h"
#include "m_argv.h"
+#include "m_misc.h"
#include "m_random.h"
#include "w_wad.h"
@@ -1169,11 +1170,95 @@
memset(&buttonlist[i],0,sizeof(button_t));
}
}
-
}
+//
+// Donut overrun emulation
+//
+// Derived from the code from PrBoom+. Thanks go to Andrey Budko (entryway)
+// as usual :-)
+//
+#define DONUT_FLOORHEIGHT_DEFAULT 0x00000000
+#define DONUT_FLOORPIC_DEFAULT 0x16
+
+static void DonutOverrun(fixed_t *s3_floorheight, short *s3_floorpic,
+ line_t *line, sector_t *pillar_sector)
+{+ static int first = 1;
+ static int tmp_s3_floorheight;
+ static int tmp_s3_floorpic;
+
+ extern int numflats;
+
+ if (first)
+ {+ int p;
+
+ // This is the first time we have had an overrun.
+ first = 0;
+
+ // Default values
+ tmp_s3_floorheight = DONUT_FLOORHEIGHT_DEFAULT;
+ tmp_s3_floorpic = DONUT_FLOORPIC_DEFAULT;
+
+ //!
+ // @category compat
+ // @arg <x> <y>
+ //
+ // Use the specified magic values when emulating behavior caused
+ // by memory overruns from improperly constructed donuts.
+ // In Vanilla Doom this can differ depending on the operating
+ // system. The default (if this option is not specified) is to
+ // emulate the behavior when running under Windows 98.
+
+ p = M_CheckParm("-donut");+
+ if (p > 0 && p < myargc - 2)
+ {+ // Dump of needed memory: (fixed_t)0000:0000 and (short)0000:0008
+ //
+ // C:\>debug
+ // -d 0:0
+ //
+ // DOS 6.22:
+ // 0000:0000 (57 92 19 00) F4 06 70 00-(16 00)
+ // DOS 7.1:
+ // 0000:0000 (9E 0F C9 00) 65 04 70 00-(16 00)
+ // Win98:
+ // 0000:0000 (00 00 00 00) 65 04 70 00-(16 00)
+ // DOSBox under XP:
+ // 0000:0000 (00 00 00 F1) ?? ?? ?? 00-(07 00)
+
+ M_StrToInt(myargv[p + 1], &tmp_s3_floorheight);
+ M_StrToInt(myargv[p + 2], &tmp_s3_floorpic);
+
+ if (tmp_s3_floorpic >= numflats)
+ {+ fprintf(stderr,
+ "DonutOverrun: The second parameter for \"-donut\" "
+ "switch should be greater than 0 and less than number "
+ "of flats (%d). Using default value (%d) instead. \n",
+ numflats, DONUT_FLOORPIC_DEFAULT);
+ tmp_s3_floorpic = DONUT_FLOORPIC_DEFAULT;
+ }
+ }
+ }
+
+ /*
+ fprintf(stderr,
+ "Linedef: %d; Sector: %d; "
+ "New floor height: %d; New floor pic: %d\n",
+ line->iLineID, pillar_sector->iSectorID,
+ tmp_s3_floorheight >> 16, tmp_s3_floorpic);
+ */
+
+ *s3_floorheight = (fixed_t) tmp_s3_floorheight;
+ *s3_floorpic = (short) tmp_s3_floorpic;
+}
+
+
//
// Special Stuff that can not be categorized
//
@@ -1186,17 +1271,19 @@
int rtn;
int i;
floormove_t* floor;
-
+ fixed_t s3_floorheight;
+ short s3_floorpic;
+
secnum = -1;
rtn = 0;
while ((secnum = P_FindSectorFromLineTag(line,secnum)) >= 0)
{s1 = §ors[secnum];
-
+
// ALREADY MOVING? IF SO, KEEP GOING...
if (s1->specialdata)
continue;
-
+
rtn = 1;
s2 = getNextSector(s1->lines[0],s1);
@@ -1217,13 +1304,34 @@
break;
}
- for (i = 0;i < s2->linecount;i++)
+ for (i = 0; i < s2->linecount; i++)
{- if ((!s2->lines[i]->flags & ML_TWOSIDED) ||
- (s2->lines[i]->backsector == s1))
- continue;
s3 = s2->lines[i]->backsector;
-
+
+ if (s3 == s1)
+ continue;
+
+ if (s3 == NULL)
+ {+ // e6y
+ // s3 is NULL, so
+ // s3->floorheight is an int at 0000:0000
+ // s3->floorpic is a short at 0000:0008
+ // Trying to emulate
+
+ fprintf(stderr,
+ "EV_DoDonut: WARNING: emulating buffer overrun due to "
+ "NULL back sector. "
+ "Unexpected behavior may occur in Vanilla Doom.\n");
+
+ DonutOverrun(&s3_floorheight, &s3_floorpic, line, s1);
+ }
+ else
+ {+ s3_floorheight = s3->floorheight;
+ s3_floorpic = s3->floorpic;
+ }
+
// Spawn rising slime
floor = Z_Malloc (sizeof(*floor), PU_LEVSPEC, 0);
P_AddThinker (&floor->thinker);
@@ -1234,9 +1342,9 @@
floor->direction = 1;
floor->sector = s2;
floor->speed = FLOORSPEED / 2;
- floor->texture = s3->floorpic;
+ floor->texture = s3_floorpic;
floor->newspecial = 0;
- floor->floordestheight = s3->floorheight;
+ floor->floordestheight = s3_floorheight;
// Spawn lowering donut-hole
floor = Z_Malloc (sizeof(*floor), PU_LEVSPEC, 0);
@@ -1248,7 +1356,7 @@
floor->direction = -1;
floor->sector = s1;
floor->speed = FLOORSPEED / 2;
- floor->floordestheight = s3->floorheight;
+ floor->floordestheight = s3_floorheight;
break;
}
}