#if 0
gcc ${CFLAGS:--s -O2} -c exec.c `sdl-config --cflags`
exit
#endif
#include "SDL.h"
#include <setjmp.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "sqlite3.h"
#include "smallxrm.h"
#include "heromesh.h"
#include "instruc.h"
#ifndef VSTACKSIZE
#define VSTACKSIZE 0x400
#endif
Uint32 max_objects;
Uint32 generation_number;
Object**objects;
Uint32 nobjects;
Value globals[0x800];
Uint32 firstobj=VOIDLINK;
Uint32 lastobj=VOIDLINK;
Uint32 playfield[64*64];
Uint8 pfwidth,pfheight;
typedef struct {
Uint16 msg;
Uint32 from;
Value arg1,arg2,arg3;
} MessageVars;
static jmp_buf my_env;
static const char*my_error;
static MessageVars msgvars;
static char lastimage_processing;
static Value vstack[VSTACKSIZE];
static int vstackptr;
#define Throw(x) (my_error=(x),longjmp(my_env,1))
#define StackReq(x,y) do{ if(vstackptr<(x)) Throw("Stack underflow"); if(vstackptr-(x)+(y)>=VSTACKSIZE) Throw("Stack overflow"); }while(0)
#define Push(x) (vstack[vstackptr++]=(x))
#define Pop() (vstack[--vstackptr])
void pfunlink(Uint32 n) {
Object*o=objects[n];
if(o->down==VOIDLINK) playfield[o->x+o->y*64-65]=o->up;
else objects[o->down]->up=o->up;
if(o->up!=VOIDLINK) objects[o->up]->down=o->down;
o->down=o->up=VOIDLINK;
}
void pflink(Uint32 n) {
Object*o=objects[n];
int p=o->x+o->y*64-65;
if(p<0) return;
if(playfield[p]==VOIDLINK) {
playfield[p]=n;
} else {
Sint32 d=o->density;
Uint32 m=playfield[p];
Uint32 t=VOIDLINK;
while(m!=VOIDLINK && objects[m]->density>=d) t=m,m=objects[m]->up;
o->down=t;
o->up=m;
if(t!=VOIDLINK) objects[t]->up=n; else playfield[p]=n;
if(m!=VOIDLINK) objects[m]->down=n;
}
}
#define OBJECT_ARRAY_BLOCK 256
Uint32 objalloc(Uint16 c) {
// Allocates a new object of the given class; links into the event list but not into the playfield.
// All fields are initialized by the class or to zero.
// Does not send any messages or otherwise notify anyone that it has been created.
// Returns VOIDLINK if object cannot be created.
Uint32 n;
Class*cl=classes[c];
Object*o=calloc(1,sizeof(Object)+cl->uservars*sizeof(Value));
if(!c || !cl || cl->cflags&(CF_GROUP|CF_NOCLASS2)) goto bad;
if(!o) fatal("Allocation failed\n");
o->class=c;
o->generation=generation_number;
#define C(x) o->x=cl->x;
C(height) C(weight) C(climb) C(density) C(volume) C(strength) C(arrivals) C(departures) C(temperature)
C(shape) C(shovable) C(oflags)
C(sharp[0]) C(sharp[1]) C(sharp[2]) C(sharp[3])
C(hard[0]) C(hard[1]) C(hard[2]) C(hard[3])
#undef C
o->misc4=NVALUE(cl->misc4);
o->misc5=NVALUE(cl->misc5);
o->misc6=NVALUE(cl->misc6);
o->misc7=NVALUE(cl->misc7);
if(nobjects) for(n=nobjects-1;;n--) {
if(!objects[n]) goto found;
if(!n) break;
}
if(nobjects>=max_objects) goto bad;
objects=realloc(objects,(nobjects+OBJECT_ARRAY_BLOCK)*sizeof(Object*));
if(!objects) fatal("Allocation failed\n");
for(n=nobjects;n<nobjects+OBJECT_ARRAY_BLOCK;n++) objects[n]=0;
n=nobjects;
nobjects+=OBJECT_ARRAY_BLOCK;
found:
o->up=o->down=o->prev=o->next=VOIDLINK;
if(cl->nmsg || classes[0]->nmsg) {
o->prev=lastobj;
if(lastobj!=VOIDLINK) objects[lastobj]->next=n;
lastobj=n;
if(firstobj==VOIDLINK) firstobj=n;
}
objects[n]=o;
return n;
bad:
free(o);
return VOIDLINK;
}
static inline int v_bool(Value v) {
switch(v.t) {
case TY_NUMBER: return v.u!=0;
case TY_SOUND: case TY_USOUND: Throw("Cannot convert sound to boolean");
default: return 1;
}
}
static Uint32 v_object(Value v) {
if(v.t==TY_NUMBER) {
if(v.u) Throw("Cannot convert number to object");
return VOIDLINK;
} else if(v.t>TY_MAXTYPE) {
if(v.u>=nobjects || !objects[v.u]) Throw("Attempt to use a nonexistent object");
if(objects[v.u]->generation!=v.t) Throw("Attempt to use a nonexistent object");
return v.u;
} else {
Throw("Cannot convert non-object to object");
}
}
// Here is where the execution of a Free Hero Mesh bytecode subroutine is executed.
static void execute_program(Uint16*code,int ptr,Uint32 obj) {
Object*o=objects[obj];
Value t1,t2;
if(StackProtection()) Throw("Call stack overflow");
for(;;) switch(code[ptr++]) {
case 0x0000 ... 0x00FF: StackReq(0,1); Push(NVALUE(code[ptr-1])); break;
case 0x0100 ... 0x01FF: StackReq(0,1); Push(NVALUE(code[ptr-1]-0x200)); break;
case 0x0200 ... 0x02FF: StackReq(0,1); Push(MVALUE(code[ptr-1]&255)); break;
case 0x0300 ... 0x03FF: StackReq(0,1); Push(UVALUE(code[ptr-1]&255,TY_SOUND)); break;
case 0x0400 ... 0x04FF: StackReq(0,1); Push(UVALUE(code[ptr-1]&255,TY_USOUND)); break;
case 0x4000 ... 0x7FFF: StackReq(0,1); Push(CVALUE(code[ptr-1]-0x4000)); break;
case 0x87E8 ... 0x87FF: StackReq(0,1); Push(NVALUE(1UL<<(code[ptr-1]&31))); break;
case 0xC000 ... 0xFFFF: StackReq(0,1); Push(NVALUE((code[ptr-1]&0x3FFF)+256)); break;
case OP_CALLSUB: execute_program(code,code[ptr++],obj); break;
case OP_DROP: StackReq(1,0); Pop(); break;
case OP_DROP_D: StackReq(2,0); Pop(); Pop(); break;
case OP_DUP: StackReq(1,2); t1=Pop(); Push(t1); Push(t1); break;
case OP_GOTO: ptr=code[ptr]; break;
case OP_IF: StackReq(1,0); if(v_bool(Pop())) ptr=code[ptr]; else ptr++; break;
case OP_INT16: StackReq(0,1); Push(NVALUE(code[ptr++])); break;
case OP_INT32: StackReq(0,1); t1=UVALUE(code[ptr++]<<16,TY_NUMBER); t1.u|=code[ptr++]; Push(t1); break;
case OP_LAND: StackReq(2,1); t1=Pop(); t2=Pop(); if(v_bool(t1) && v_bool(t2)) Push(NVALUE(1)); else Push(NVALUE(0)); break;
case OP_LNOT: StackReq(1,1); if(v_bool(Pop())) Push(NVALUE(0)); else Push(NVALUE(1)); break;
case OP_LOR: StackReq(2,1); t1=Pop(); t2=Pop(); if(v_bool(t1) || v_bool(t2)) Push(NVALUE(1)); else Push(NVALUE(0)); break;
case OP_NIP: StackReq(2,1); t1=Pop(); Pop(); Push(t1); break;
case OP_RET: return;
case OP_SWAP: StackReq(2,2); t1=Pop(); t2=Pop(); Push(t1); Push(t2); break;
default: Throw("Internal error: Unrecognized opcode");
}
}
static Value send_message(Uint32 from,Uint32 to,Uint16 msg,Value arg1,Value arg2,Value arg3) {
MessageVars saved=msgvars;
Uint16 c=objects[to]->class;
Uint16 p=get_message_ptr(c,msg);
Uint16*code;
int stackptr=vstackptr;
if(p==0xFFFF) {
p=get_message_ptr(0,msg);
if(!p) return NVALUE(0);
code=classes[0]->codes;
} else {
code=classes[c]->codes;
}
msgvars=(MessageVars){msg,from,arg1,arg2,arg3};
execute_program(code,p,to);
msgvars=saved;
if(vstackptr<stackptr) Throw("Message code used up too much data from stack");
if(vstackptr>stackptr+1) Throw("Message code left too much data on stack");
if(vstackptr==stackptr) {
return NVALUE(0);
} else {
return Pop();
}
}
void annihilate(void) {
Uint32 i;
for(i=0;i<64*64;i++) playfield[i]=VOIDLINK;
firstobj=lastobj=VOIDLINK;
if(!objects) return;
for(i=0;i<nobjects;i++) free(objects[i]);
nobjects=0;
free(objects);
objects=0;
}
const char*execute_turn(int key) {
if(setjmp(my_env)) return my_error;
lastimage_processing=0;
vstackptr=0;
return 0;
}