scummvm/engines/saga2/interp.cpp
2023-05-14 22:57:11 +02:00

1949 lines
54 KiB
C++

/* ScummVM - Graphic Adventure Engine
*
* ScummVM is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*
* Based on the original sources
* Faery Tale II -- The Halls of the Dead
* (c) 1993-1996 The Wyrmkeep Entertainment Co.
*/
#include "common/debug.h"
#include "saga2/saga2.h"
#include "saga2/fta.h"
#include "saga2/script.h"
#include "saga2/code.h"
#include "saga2/tile.h"
#include "saga2/mission.h"
#include "saga2/hresmgr.h"
#include "saga2/saveload.h"
#include "saga2/actor.h"
namespace Saga2 {
#define IMMED_WORD(w) ((w = *pc++),(w |= (*pc++)<<8)); \
debugC(3, kDebugScripts, "IMMED_WORD(%d 0x%04x)", w, w)
#define BRANCH(w) pc = _codeSeg + (w); \
debugC(3, kDebugScripts, "BRANCH(%ld 0x%04lx)", long(pc - _codeSeg), long(pc - _codeSeg))
const uint32 sagaID = MKTAG('S', 'A', 'G', 'A'),
dataSegID = MKTAG('_', '_', 'D', 'A'),
exportSegID = MKTAG('_', 'E', 'X', 'P');
const int initialStackFrameSize = 10;
static bool lookupExport(uint16 entry, uint16 &segNum, uint16 &segOff);
uint8 *segmentAddress(uint16 segment, uint16 offset);
Thread *thisThread;
struct ModuleEntry *moduleList; // loaded from resource
int16 moduleBaseResource,
moduleCount;
uint16 dataSegIndex; // saved index of data seg
byte *dataSegment, // loaded in data
*exportSegment; // export table from SAGA
int32 dataSegSize; // bytes in data segment
long exportCount; // number of exported syms
// An extended script is running -- suspend all background processing.
int16 extendedThreadLevel;
int16 lastExport;
extern hResource *scriptResFile; // script resources
hResContext *scriptRes; // script resource handle
void script_error(const char *msg) {
thisThread->_flags |= Thread::kTFAborted;
WriteStatusF(0, msg);
}
static Common::String seg2str(int16 segment) {
switch (segment) {
case kBuiltinTypeObject:
return "GameObject";
case kBuiltinTypeTAG:
return "TAG";
case kBuiltinAbstract:
return Common::String::format("Abstract%d", segment);
case kBuiltinTypeMission:
return "Mission";
default:
return Common::String::format("%d", segment);
}
}
//-----------------------------------------------------------------------
// Return the address of a builtin object, such as an Actor or a TAG,
// given a segment number and an index
uint8 *builtinObjectAddress(int16 segment, uint16 index) {
uint16 segNum, segOff;
switch (segment) {
case kBuiltinTypeObject:
return (uint8 *)(&GameObject::objectAddress(index)->_data);
case kBuiltinTypeTAG:
return (uint8 *)(&ActiveItem::activeItemAddress(index)->_data);
case kBuiltinAbstract:
assert(index > 0);
if (lookupExport(index, segNum, segOff) == false)
error("SAGA: Cannot take address of abtract class");
return segmentAddress(segNum, segOff);
case kBuiltinTypeMission:
return (uint8 *)(&ActiveMission::missionAddress(index)->_data);
default:
error("Invalid builtin object segment number: %d\n", segment);
}
}
//-----------------------------------------------------------------------
// Given the builtin object type (SAGA segment number), and the address
// from builtinObjectAddress(), return the address of the virtual
// function table for the class associated with this object. Also
// return the address of the C function call table for this builtin
// class.
uint16 *builtinVTableAddress(int16 btype, uint8 *addr, CallTable **callTab) {
GameObject *obj;
ActiveItem *aItem;
ActiveMission *aMission;
uint16 script,
vtSeg,
vtOffset;
switch (btype) {
case kBuiltinTypeObject:
// Get the address of a game object using the ID
obj = ((ObjectData *)addr)->obj;
script = obj->scriptClass();
*callTab = &actorCFuncs;
if (script <= 0)
error("SAGA failure: GameObject %d (%s) has no script.\n", obj->thisID(), obj->proto() ? obj->objName() : "Unknown");
break;
case kBuiltinTypeTAG:
aItem = ((ActiveItemData *)addr)->aItem;
script = aItem->_data.scriptClassID;
*callTab = &tagCFuncs;
if (script <= 0)
error("SAGA failure: TAG has no script.\n");
break;
case kBuiltinTypeMission:
aMission = ((ActiveMissionData *)addr)->aMission;
script = aMission->getScript();
*callTab = &missionCFuncs;
if (script <= 0)
error("SAGA failure: Mission Object has no script.\n");
break;
case kBuiltinAbstract:
*callTab = nullptr;
return (uint16 *)addr;
default:
error("SAGA Failure: Attempt to call member function of invalid builtin type.\n");
}
// Look up the vtable in the export table.
if (script != 0 && lookupExport(script, vtSeg, vtOffset)) {
return (uint16 *)segmentAddress(vtSeg, vtOffset);
} else
return nullptr;
}
uint8 *segmentAddress(uint16 segment, uint16 offset) {
byte *segHandle = nullptr;
// A segment number of less than zero means that this is
// a "builtin" object, in other words the game engine itself
if ((int16)segment < 0)
return builtinObjectAddress(segment, offset);
segHandle = scriptRes->loadIndexResource(segment, "object segment");
if (segHandle == nullptr)
return nullptr;
return segHandle + offset;
}
uint8 *segmentArrayAddress(uint16 segment, uint16 index) {
byte *segHandle = nullptr;
if ((int16)segment < 0)
return builtinObjectAddress(segment, index);
segHandle = scriptRes->loadIndexResource(segment, "object array segment");
if (segHandle == nullptr)
return nullptr;
return segHandle + sizeof(uint16) + (uint16)(index * READ_LE_INT16(segHandle));
}
// Returns the address of a byte given an addressing mode
uint8 *byteAddress(Thread *th, uint8 **pcPtr) {
uint8 *pc = *pcPtr,
*addr;
uint16 seg,
offset, offset2,
index,
*arg;
switch (*pc++) {
case skAddrData:
IMMED_WORD(offset);
debugC(3, kDebugScripts, "byteAddress: data[%d] = %d", offset, dataSegment[offset]);
*pcPtr = pc;
return &dataSegment[offset];
case skAddrNear:
IMMED_WORD(offset);
debugC(3, kDebugScripts, "byteAddress: near[%d] = %d", offset, th->_codeSeg[offset]);
*pcPtr = pc;
return th->_codeSeg + offset;
case skAddrFar:
IMMED_WORD(seg);
IMMED_WORD(offset);
debugC(3, kDebugScripts, "byteAddress: far[%s:%d] = %d", seg2str(seg).c_str(), offset, *segmentAddress(seg, offset));
*pcPtr = pc;
// FIXME: WORKAROUND: Fixes Captain Navis (5299, 17715, 80) in Maldavith not allowing passage to the Tamnath Ruins through sail even if Muybridge is dead.
if (seg == 130 && offset == 2862) {
warning("WORKAROUND: byteAddress: far");
Actor *boss = (Actor *)GameObject::objectAddress(32880);
if (boss->isDead())
return segmentAddress(130, 0);
}
return segmentAddress(seg, offset);
case skAddrArray:
IMMED_WORD(seg);
IMMED_WORD(offset);
addr = segmentArrayAddress(seg, offset);
IMMED_WORD(offset2);
debugC(3, kDebugScripts, "byteAddress: array[%s:%d:%d] = %d", seg2str(seg).c_str(), offset, offset2, addr[offset2]);
*pcPtr = pc;
return addr + offset2;
case skAddrStack:
IMMED_WORD(offset);
debugC(3, kDebugScripts, "byteAddress: stack[%d] = %d", offset, *(th->_stackBase + th->_framePtr + (int16)offset));
*pcPtr = pc;
return th->_stackBase + th->_framePtr + (int16)offset;
case skAddrThread:
IMMED_WORD(offset);
debugC(3, kDebugScripts, "byteAddress: thread[%d] = %d", offset, *((uint8 *)&th->_threadArgs + offset));
*pcPtr = pc;
return (uint8 *)&th->_threadArgs + offset;
case skAddrThis:
IMMED_WORD(offset);
arg = (uint16 *)(th->_stackBase + th->_framePtr + 8);
*pcPtr = pc;
if (arg[0] == dataSegIndex) {
debugC(3, kDebugScripts, "byteAddress: thisD[%d:%d] = %d", arg[1], offset, dataSegment[arg[1] + offset]);
return &dataSegment[arg[1] + offset];
}
debugC(3, kDebugScripts, "byteAddress: thisS[%s:%d:%d] = %d", seg2str(arg[0]).c_str(), arg[1], offset, *(segmentArrayAddress(arg[0], arg[1]) + offset));
return segmentArrayAddress(arg[0], arg[1]) + offset;
case skAddrDeref:
// First, get the address of the reference.
*pcPtr = pc;
addr = byteAddress(th, pcPtr);
pc = *pcPtr;
// Get the offset from the reference variable.
index = *(uint16 *)addr;
// Get the segment to dereference from, and the offset
// within the object.
IMMED_WORD(seg);
IMMED_WORD(offset);
debugC(3, kDebugScripts, "byteAddress: deref[%s:%d:%d] = %d", seg2str(seg).c_str(), index, offset, *(segmentAddress(seg, index) + offset));
*pcPtr = pc;
// Compute address of object
return segmentAddress(seg, index) + offset;
}
error("byteAddress: Invalid addressing mode: %d.\n", **pcPtr);
}
// Returns the address of an object given an addressing mode
uint8 *objectAddress(
Thread *th,
uint8 **pcPtr,
uint16 &segNum, // segment of start of object
uint16 &offs) { // offset of start of object
uint8 *pc = *pcPtr,
*addr;
uint16 seg,
offset = 0,
index,
*arg;
switch (*pc++) {
case skAddrData:
IMMED_WORD(index);
seg = dataSegIndex;
addr = &dataSegment[index];
debugC(3, kDebugScripts, "objectAddress: data[%s:%d] = %d", seg2str(seg).c_str(), index, *addr);
break;
case skAddrFar:
IMMED_WORD(seg);
IMMED_WORD(index);
addr = segmentAddress(seg, index);
debugC(3, kDebugScripts, "objectAddress: far[%s:%d] = %d", seg2str(seg).c_str(), index, *addr);
break;
case skAddrArray:
IMMED_WORD(seg);
IMMED_WORD(index);
IMMED_WORD(offset);
addr = segmentArrayAddress(seg, index) + offset;
debugC(3, kDebugScripts, "objectAddress: array[%s:%d:%d] = %d", seg2str(seg).c_str(), index, offset, *addr);
break;
case skAddrThis:
IMMED_WORD(offset);
arg = (uint16 *)(th->_stackBase + th->_framePtr + 8);
seg = arg[0];
index = arg[1];
if (seg == dataSegIndex) {
debugC(3, kDebugScripts, "objectAddress: thisD[%d:%d] = %d", index, offset, dataSegment[index + offset]);
return &dataSegment[index + offset];
}
addr = segmentArrayAddress(seg, index) + offset;
debugC(3, kDebugScripts, "objectAddress: thisS[%s:%d:%d] = %d", seg2str(seg).c_str(), index, offset, *addr);
break;
case skAddrDeref:
// First, get the address of the reference.
*pcPtr = pc;
addr = byteAddress(th, pcPtr);
pc = *pcPtr;
// Get the offset from the reference variable.
index = *(uint16 *)addr;
// Get the segment to dereference from, and the offset
// within the object.
IMMED_WORD(seg);
IMMED_WORD(offset);
// Compute address of object
addr = segmentAddress(seg, index) + offset;
debugC(3, kDebugScripts, "objectAddress: deref[%s:%d:%d] = %d", seg2str(seg).c_str(), index, offset, *addr);
break;
default:
error("objectAddress: Invalid addressing mode: %d.\n", **pcPtr);
}
offs = index;
segNum = seg;
*pcPtr = pc;
return addr;
}
// Returns the address and access mask of a bit, given addressing mode
uint8 *bitAddress(Thread *th, uint8 **pcPtr, int16 *mask) {
uint8 *pc = *pcPtr,
*addr;
uint16 seg,
offset;
switch (*pc++) {
case skAddrData:
IMMED_WORD(offset);
*pcPtr = pc;
*mask = (1 << (offset & 7));
debugC(3, kDebugScripts, "bitAddress: data[%d] = %d", offset, (dataSegment[offset >> 3] & *mask) != 0);
return &dataSegment[(offset >> 3)];
case skAddrNear:
IMMED_WORD(offset);
*pcPtr = pc;
*mask = (1 << (offset & 7));
debugC(3, kDebugScripts, "bitAddress: near[%d] = %d", offset, (*(th->_codeSeg + (offset >> 3)) & *mask) != 0);
return th->_codeSeg + (offset >> 3);
case skAddrFar:
IMMED_WORD(seg);
IMMED_WORD(offset);
*pcPtr = pc;
*mask = (1 << (offset & 7));
debugC(3, kDebugScripts, "bitAddress: far[%s:%d] = %d", seg2str(seg).c_str(), offset, (*segmentAddress(seg, offset >> 3) & *mask) != 0);
return segmentAddress(seg, (offset >> 3));
case skAddrArray:
IMMED_WORD(seg);
IMMED_WORD(offset);
addr = segmentArrayAddress(seg, offset);
IMMED_WORD(offset);
*pcPtr = pc;
*mask = (1 << (offset & 7));
debugC(3, kDebugScripts, "bitAddress: array[%s:%d:%d] = %d", seg2str(seg).c_str(), offset, offset, (addr[offset >> 3] & *mask) != 0);
return addr + (offset >> 3);
case skAddrStack:
IMMED_WORD(offset);
*pcPtr = pc;
*mask = (1 << (offset & 7));
debugC(3, kDebugScripts, "bitAddress: stack[%d] = %d", offset, (*(th->_stackBase + th->_framePtr + (offset >>3)) & *mask) != 0);
return th->_stackBase + th->_framePtr + (offset >> 3);
case skAddrThread:
IMMED_WORD(offset);
*pcPtr = pc;
*mask = (1 << (offset & 7));
debugC(3, kDebugScripts, "bitAddress: thread[%d] = %d", offset, (*((uint8 *)&th->_threadArgs + (offset >> 3)) & *mask) != 0);
return (uint8 *)&th->_threadArgs + (offset >> 3);
case skAddrThis:
error("Addressing relative to 'this' not supported just yet.\n");
}
error("bitAddress: Invalid addressing mode: %d.\n", **pcPtr);
}
// Returns the address of a string
uint8 *Thread::strAddress(int strNum) {
uint16 seg = READ_LE_INT16(_codeSeg + 2);
uint16 offset = READ_LE_INT16(_codeSeg + 4);
uint8 *strSeg = segmentAddress(seg, offset);
assert(strNum >= 0);
assert(_codeSeg);
assert(strSeg);
return strSeg + (uint16)READ_LE_INT16(strSeg + 2 * strNum);
}
//-----------------------------------------------------------------------
// RandomGenerator class - a random number generator class for function
// objects which each maintain a local seed.
class RandomGenerator {
uint32 _a; // seed
static const uint32 _b; // arbitrary constant
public:
RandomGenerator() : _a(1) {
}
RandomGenerator(uint16 seed) {
_a = (uint32)seed << 16;
}
void seed(uint16 seed) {
_a = (uint32)seed << 16;
}
uint16 operator()() {
_a = (_a * _b) + 1;
return _a >> 16;
}
};
const uint32 RandomGenerator::_b = 31415821;
//-----------------------------------------------------------------------
// A restricted random function
int16 RRandom(int16 c, int16 s, int16 id) {
// Create a local random number generator with a seed calculated
// with a non-deterministic portion generated by the standard
// library rand() function and a deterministic potion based upon
// the "id" argument
RandomGenerator rnd(g_vm->_rnd->getRandomNumber(s - 1) + (id * s));
return rnd() % c;
}
/* ============================================================================ *
Main interpreter
* ============================================================================ */
void print_script_name(uint8 *codePtr, const char *descr = nullptr) {
char scriptName[32];
uint8 *sym = codePtr - 1;
uint8 length = MIN<uint>(*sym, sizeof scriptName - 1);
memcpy(scriptName, sym - *sym, length);
scriptName[length] = '\0';
if (descr)
debugC(1, kDebugScripts, "Scripts: %d kOpEnter: [%s].%s ", lastExport, descr, scriptName);
else
debugC(1, kDebugScripts, "Scripts: %d kOpEnter: ::%s ", lastExport, scriptName);
}
const char *objectName(int16 segNum, uint16 segOff) {
//static nameBuf[64];
if (segNum >= 0)
return "SagaObject";
switch (segNum) {
case kBuiltinTypeObject:
return GameObject::objectAddress(segOff)->objName();
case kBuiltinTypeTAG:
return "Tag";
case kBuiltinAbstract:
return "@";
case kBuiltinTypeMission:
return "Mission";
}
return "???";
}
#define STACK_PRINT_DEPTH 30
static void print_stack(int16 *_stackBase, int16 *stack) {
int16 *end = (int16 *)((byte *)_stackBase + kStackSize - initialStackFrameSize);
int size = end - stack;
if (size > STACK_PRINT_DEPTH)
end = stack + STACK_PRINT_DEPTH;
debugCN(3, kDebugScripts, "stack size: %d: [", size);
for (int16 *i = stack; i < end; i++)
debugCN(3, kDebugScripts, "%d ", *i);
if (size > STACK_PRINT_DEPTH)
debugCN(3, kDebugScripts, "... ");
debugC(3, kDebugScripts, "]");
}
#define D_OP(x) debugC(1, kDebugScripts, "[%04ld 0x%04lx]: %s", long(pc - _codeSeg - 1), long(pc - _codeSeg - 1), #x)
#define D_OP1(x) debugC(1, kDebugScripts, "[%04ld 0x%04lx]: %s = %d", long(pc - _codeSeg - 1), long(pc - _codeSeg - 1), #x, *stack)
#define D_OP2(x) debugC(1, kDebugScripts, "[%04ld 0x%04lx]: %s [%p] = %d", long(pc - _codeSeg - 1), long(pc - _codeSeg - 1), #x, (void *)addr, *stack)
#define D_OP3(x) debugC(1, kDebugScripts, "[%04ld 0x%04lx]: %s [%p] %d", long(pc - _codeSeg - 1), long(pc - _codeSeg - 1), #x, (void *)addr, *addr)
bool Thread::interpret() {
uint8 *pc,
*addr;
int16 *stack = (int16 *)_stackPtr;
int16 instruction_count;
uint8 op;
int16 w,
n;
C_Call *cfunc;
pc = (_codeSeg) + _programCounter.offset;
thisThread = this; // set current thread address
for (instruction_count = 0; instruction_count < maxTimeSlice; instruction_count++) {
print_stack((int16 *)_stackBase, stack);
switch (op = *pc++) {
case kOpDup:
--stack;
*stack = stack[1]; // duplicate value on stack
D_OP1(kOpDup);
break;
case kOpDrop: // drop word on stack
D_OP(kOpDrop);
stack++;
break;
case kOpZero: // constant integer of zero
D_OP(kOpZero);
*--stack = 0; // push integer on stack
break;
case kOpOne: // constant integer of one
D_OP(kOpOne);
*--stack = 1; // push integer on stack
break;
case kOpStrlit: // string literal (also pushes word)
case kOpConstint: // constant integer
IMMED_WORD(w); // pick up word after opcode
*--stack = w; // push integer on stack
if (op == kOpStrlit)
D_OP1(kOpStrlit);
else
D_OP1(kOpConstint);
break;
case kOpGetflag: // get a flag
addr = bitAddress(this, &pc, &w); // get address of bit
*--stack = ((*addr) & w) ? 1 : 0; // true or false if bit set
D_OP2(kOpGetflag);
break;
case kOpGetint: // read from integer field (mode)
addr = byteAddress(this, &pc); // get address of integer
*--stack = *(uint16 *)addr; // get integer from address
D_OP2(kOpGetint);
break;
case kOpGetbyte: // read from integer field (mode)
addr = byteAddress(this, &pc); // get address of integer
*--stack = *addr; // get byte from address
D_OP2(kOpGetbyte);
break;
// Note that in the current implementation, "put" ops leave
// the value that was stored on the stack. We mat also do a
// 'vput' which consumes the variable.
case kOpPutflag: // put to flag bit (mode)
addr = bitAddress(this, &pc, &w); // get address of bit
if (*stack) *addr |= w; // set bit if stack non-zero
else *addr &= ~w; // else clear it
D_OP3(kOpPutflag);
break;
case kOpPutflagV: // put to flag bit (mode)
addr = bitAddress(this, &pc, &w); // get address of bit
if (*stack++) *addr |= w; // set bit if stack non-zero
else *addr &= ~w; // else clear it
D_OP3(kOpPutflagV);
break;
case kOpPutint: // put to integer field (mode)
addr = byteAddress(this, &pc); // get address of integer
*(uint16 *)addr = *stack; // put integer to address
D_OP3(kOpPutint);
break;
case kOpPutintV: // put to integer field (mode)
addr = byteAddress(this, &pc); // get address of integer
*(uint16 *)addr = *stack++; // put integer to address
D_OP3(kOpPutintV);
break;
case kOpPutbyte: // put to byte field (mode)
addr = byteAddress(this, &pc); // get address of integer
*addr = *stack; // put integer to address
D_OP3(kOpPutbyte);
break;
case kOpPutbyteV: // put to byte field (mode)
addr = byteAddress(this, &pc); // get address of integer
*addr = *stack++; // put integer to address
D_OP3(kOpPutbyteV);
break;
case kOpEnter:
D_OP(kOpEnter);
print_script_name(pc - 1);
*--stack = _framePtr; // save old frame ptr on stack
_framePtr = (uint8 *)stack - _stackBase; // new frame pointer
IMMED_WORD(w); // pick up word after address
stack -= w / 2; // make room for the locals!
break;
// function calls
case kOpReturn: // return with value
D_OP(kOpReturn);
_returnVal = *stack++;
// fall through
case kOpReturn_v: // return with void
D_OP(kOpReturn_v);
stack = (int16 *)(_stackBase + _framePtr); // pop autos
_framePtr = *stack++; // restore frame pointer
if (stack >= (int16 *)(_stackBase + _stackSize - initialStackFrameSize)) {
// Halt the thread here, wait for death
_programCounter.offset = (pc - (_codeSeg));
_stackPtr = (uint8 *)stack;
_flags |= kTFFinished;
return true;
} else {
_programCounter.segment = *stack++;
_programCounter.offset = *stack++;
//RUnlockHandle((RHANDLE)_codeSeg);
_codeSeg = scriptRes->loadIndexResource(_programCounter.segment, "saga code segment");
pc = (_codeSeg) + _programCounter.offset;
n = *stack++; // get argument count from call
stack += n; // pop that many args
if (op == kOpReturn) // if not void
*--stack = _returnVal;// push return value
}
break;
case kOpCallNear: // call function in same seg
D_OP(kOpCallNear);
n = *pc++; // get argument count
_programCounter.offset = (pc + 2 - _codeSeg);
*--stack = n; // push number of args (16 bits)
// push the program counter
*--stack = _programCounter.offset;
*--stack = _programCounter.segment;
IMMED_WORD(w); // pick up segment offset
_programCounter.offset = w; // store into pc
pc = _codeSeg + w; // calculate PC address
print_script_name(pc);
break;
case kOpCallFar: // call function in other seg
D_OP(kOpCallFar);
n = *pc++; // get argument count
_programCounter.offset = (pc + 4 - _codeSeg);
*--stack = n; // push number of args (16 bits)
// push the program counter
*--stack = _programCounter.offset;
*--stack = _programCounter.segment;
IMMED_WORD(w); // pick up segment number
_programCounter.segment = w; // set current segment
//RUnlockHandle((RHANDLE)_codeSeg);
_codeSeg = scriptRes->loadIndexResource(w, "saga code segment");
IMMED_WORD(w); // pick up segment offset
_programCounter.offset = w; // store into pc
pc = _codeSeg + w; // calculate PC address
print_script_name(pc);
break;
case kOpCcall: // call C function
case kOpCcallV: // call C function
if (op == kOpCcall)
D_OP(kOpCcall);
else
D_OP(op_call_v);
n = *pc++; // get argument count
IMMED_WORD(w); // get function number
if (w < 0 || w >= globalCFuncs.numEntries)
error("Invalid function number");
cfunc = globalCFuncs.table[w];
_argCount = n;
_returnVal = cfunc(stack); // call the function
stack += n; // pop args of of the stack
if (op == kOpCcall) { // push the return value
*--stack = _returnVal; // onto the stack
_flags |= kTFExpectResult; // script expecting result
} else _flags &= ~kTFExpectResult; // script not expecting result
// if the thread is asleep, then no more instructions
if (_flags & kTFAsleep)
instruction_count = maxTimeSlice; // break out of loop!
break;
case kOpCallMember: // call member function
case kOpCallMemberV: // call member function ()
if (op == kOpCallMember)
D_OP(kOpCallMember);
else
D_OP(kOpCallMemberV);
n = *pc++; // get argument count
w = *pc++; // index of member function
{
uint16 *vtable,
*vtableEntry,
seg,
offset;
// REM: We need a more deterministic way to
// set up the c function tables.
CallTable *callTab = &globalCFuncs;
// Get the address of the object
addr = objectAddress(this, &pc, seg, offset);
// Handle the case of a builtin object which computes the
// vtable address in a different way.
if ((int16)seg < 0) {
vtable = builtinVTableAddress((int16)seg, addr, &callTab);
} else {
vtable = (uint16 *)segmentAddress(((int16 *)addr)[0],
((int16 *)addr)[1]);
}
vtableEntry = vtable + (w * 2);
if (vtable == nullptr) {
// Do nothing...
} else if (vtableEntry[0] != 0xffff) { // It's a SAGA func
_programCounter.offset = (pc - _codeSeg);
// Push the address of the object
*--stack = offset;
*--stack = seg;
// Push number of args. including 'this'
*--stack = n + 2;
// push the program counter
*--stack = _programCounter.offset;
*--stack = _programCounter.segment;
// Get the segment of the member function, and
// determine it's real address (save segment number
// into thread).
w = vtableEntry[0];
_programCounter.segment = w;
//RUnlockHandle((RHANDLE)_codeSeg);
_codeSeg = scriptRes->loadIndexResource(w, "saga code segment");
// store pc-offset into pc
_programCounter.offset = vtableEntry[1];
// calculate PC address
pc = (_codeSeg) + _programCounter.offset;
print_script_name(pc, objectName(seg, offset));
break;
} else if (vtableEntry[1] != 0xffff) { // It's a C func
// Save the ID of the invoked object
ObjectID saveID = _threadArgs.invokedObject;
// Get the function number
w = vtableEntry[1];
if (w < 0 || w >= callTab->numEntries)
error("Invalid member function number");
// Set up thread-specific vars
_thisObject = addr;
_argCount = n;
_threadArgs.invokedObject = offset;
// Get address of function and call it.
cfunc = callTab->table[w];
_returnVal = cfunc(stack); // call the function
// Restore object ID from thread args
_threadArgs.invokedObject = saveID;
// Pop args off of the stack
stack += n;
// Push the return value onto the stack if it's
// not a 'void' call.
if (op == kOpCallMember) {
*--stack = _returnVal; // onto the stack
_flags |= kTFExpectResult; // script expecting result
} else _flags &= ~kTFExpectResult; // script not expecting result
// if the thread is asleep, then break interpret loop
if (_flags & kTFAsleep) instruction_count = maxTimeSlice;
break;
}
// else it's a NULL function (i.e. pure virtual)
}
// REM: Call the member function
if (op == kOpCallMember) // push the return value
*--stack = 0; // onto the stack
break;
case kOpJmpTrueV:
D_OP(kOpJmpTrueV);
IMMED_WORD(w); // pick up word after address
if (*stack++ != 0) {
BRANCH(w); // if stack is non-zero, jump
}
break;
case kOpJmpFalseV:
D_OP(kOpJmpFalseV);
IMMED_WORD(w); // pick up word after address
if (*stack++ == 0) {
BRANCH(w); // if stack is zero, jump
}
break;
case kOpJmpTrue:
D_OP(op_true);
IMMED_WORD(w); // pick up word after address
if (*stack != 0) {
BRANCH(w); // if stack is non-zero. jump
}
break;
case kOpJmpDalse:
D_OP(op_false);
IMMED_WORD(w); // pick up word after address
if (*stack == 0) {
BRANCH(w); // if stack is zero, jump
}
break;
case kOpJmp:
D_OP(kOpJmp);
IMMED_WORD(w); // pick up word after address
BRANCH(w); // jump relative to module
break;
case kOpJmpSwitch:
D_OP(kOpJmpSwitch);
IMMED_WORD(n); // n = number of cases
w = *stack++; // w = value on stack
{
uint16 val,
jmp;
while (n--) {
IMMED_WORD(val); // val = case value
IMMED_WORD(jmp); // jmp = address to jump to
debugC(3, kDebugScripts, "Case %d: jmp %d", val, jmp);
if (w == val) { // if case values match
BRANCH(jmp); // jump to case
break;
}
}
if (n < 0) {
IMMED_WORD(jmp); // def = jump offset for default
BRANCH(jmp); // take default jump
}
}
break;
case kOpJmp_seedrandom: // seeded random jump
case kOpJmpRandom: // random jump
if (op == kOpJmp_seedrandom)
D_OP(kOpJmp_seedrandom);
else
D_OP(op_random);
if (op == kOpJmpRandom) {
IMMED_WORD(n); // n = number of cases
IMMED_WORD(n); // total probability
n = (uint16)(g_vm->_rnd->getRandomNumber(n - 1)); // random number between 0 and n-1
} else {
int16 seed,
r;
seed = *stack++; // the seed value
IMMED_WORD(r); // n = restriction
IMMED_WORD(n); // n = number of cases
IMMED_WORD(n); // total probability
n = RRandom(n, r, seed);
}
for (;;) {
uint16 val,
jmp;
IMMED_WORD(val); // val = probability of this case
IMMED_WORD(jmp); // jmp = address to jump to
n -= val; // subtract prob from overall prob
if (n < 0) { // if number within range
BRANCH(jmp); // jump to prob
break;
}
}
break;
case kOpNegate:
D_OP(kOpNegate);
*stack = - *stack;
break; // negate TOS
case kOpNot:
D_OP(kOpNot);
*stack = ! *stack;
break; // not TOS
case kOpCompl:
D_OP(kOpCompl);
*stack = ~ *stack;
break; // complement TOS
case kOpIncV:
D_OP(kOpIncV);
addr = byteAddress(this, &pc); // get address of integer
*(uint16 *)addr += 1; // bump value by one
break;
case kOpDecV:
D_OP(kOpDecV);
addr = byteAddress(this, &pc); // get address of integer
*(uint16 *)addr -= 1; // bump value by one
break;
case kOpPostinc:
D_OP(kOpPostinc);
addr = byteAddress(this, &pc); // get address of integer
*--stack = *(uint16 *)addr; // get integer from address
*(uint16 *)addr += 1; // bump value by one
break;
case kOpPostdec:
D_OP(kOpPostdec);
addr = byteAddress(this, &pc); // get address of integer
*--stack = *(uint16 *)addr; // get integer from address
*(uint16 *)addr -= 1; // bump value by one
break;
// Binary ops. Since I don't know the order of evaluation of
// These C operations, I use a temp variable. Note that
// stack is incremented before storing to skip over the
// dropped variable.
case kOpAdd:
D_OP(kOpAdd);
w = (stack[1] + stack[0]);
*++stack = w;
break;
case kOpSub:
D_OP(kOpSub);
w = (stack[1] - stack[0]);
*++stack = w;
break;
case kOpMul:
D_OP(kOpMul);
w = (stack[1] * stack[0]);
*++stack = w;
break;
case kOpDiv:
D_OP(kOpDiv);
w = (stack[1] / stack[0]);
*++stack = w;
break;
case kOpMod:
D_OP(kOpMod);
w = (stack[1] % stack[0]);
*++stack = w;
break;
case kOpEq:
D_OP(kOpEq);
w = (stack[1] == stack[0]);
*++stack = w;
break;
case kOpNe:
D_OP(kOpNe);
w = (stack[1] != stack[0]);
*++stack = w;
break;
case kOpGt:
D_OP(kOpGt);
w = (stack[1] > stack[0]);
*++stack = w;
break;
case kOpLt:
D_OP(kOpLt);
w = (stack[1] < stack[0]);
*++stack = w;
break;
case kOpGe:
D_OP(kOpGe);
w = (stack[1] >= stack[0]);
*++stack = w;
break;
case kOpLe:
D_OP(kOpLe);
w = (stack[1] <= stack[0]);
*++stack = w;
break;
case kOpRsh:
D_OP(kOpRsh);
w = (stack[1] >> stack[0]);
*++stack = w;
break;
case kOpLsh:
D_OP(kOpLsh);
w = (stack[1] << stack[0]);
*++stack = w;
break;
case kOpAnd:
D_OP(kOpAnd);
w = (stack[1] & stack[0]);
*++stack = w;
break;
case kOpOr:
D_OP(kOpOr);
w = (stack[1] | stack[0]);
*++stack = w;
break;
case kOpXor:
D_OP(kOpXor);
w = (stack[1] ^ stack[0]);
*++stack = w;
break;
case kOpLand:
D_OP(kOpLand);
w = (stack[1] && stack[0]);
*++stack = w;
break;
case kOpLor:
D_OP(kOpLor);
w = (stack[1] || stack[0]);
*++stack = w;
break;
case kOpLxor:
D_OP(kOpLxor);
w = (stack[1] && !stack[0]) || (!stack[1] && stack[0]);
*++stack = w;
break;
case kOpSpeak:
case kOpDialogBegin:
case kOpDialogEnd:
case kOpReply:
case kOpAnimate:
script_error("Feature not implemented.\n");
break;
default:
script_error("fatal error: undefined opcode");
break;
}
}
_programCounter.offset = (pc - (_codeSeg));
_stackPtr = (uint8 *)stack;
return false;
}
/* ============================================================================ *
ThreadList class
* ============================================================================ */
class ThreadList {
enum {
kNumThreads = 25
};
Thread *_list[kNumThreads];
public:
// Constructor
ThreadList() {
for (uint i = 0; i < kNumThreads; i++)
_list[i] = nullptr;
}
void read(Common::InSaveFile *in);
// Return the number of bytes needed to archive this thread list
// in an archive buffer
int32 archiveSize();
void write(Common::MemoryWriteStreamDynamic *out);
// Cleanup the active threads
void cleanup();
// Place a thread back into the inactive list
void deleteThread(Thread *p);
void newThread(Thread *p, ThreadID id);
void newThread(Thread *p);
// Return the specified thread's ID
ThreadID getThreadID(Thread *thread) {
for (uint i = 0; i < kNumThreads; i++) {
if (_list[i] == thread)
return i;
}
error("Unknown thread address: %p", (void *)thread);
}
// Return a pointer to a thread, given an ID
Thread *getThreadAddress(ThreadID id) {
return _list[id];
}
// Return a pointer to the first active thread
Thread *first();
Thread *next(Thread *thread);
};
void ThreadList::read(Common::InSaveFile *in) {
int16 threadCount;
// Get the count of threads and increment the buffer pointer
threadCount = in->readSint16LE();
debugC(3, kDebugSaveload, "... threadCount = %d", threadCount);
// Iterate through the archive data, reconstructing the Threads
for (int i = 0; i < threadCount; i++) {
debugC(3, kDebugSaveload, "Saving Thread %d", i);
ThreadID id;
// Retreive the Thread's id number
id = in->readSint16LE();
debugC(4, kDebugSaveload, "...... id = %d", id);
new Thread(in, id);
}
}
int32 ThreadList::archiveSize() {
int32 size = sizeof(int16);
for (uint i = 0; i < kNumThreads; i++) {
if (_list[i])
size += sizeof(ThreadID) + _list[i]->archiveSize();
}
return size;
}
void ThreadList::write(Common::MemoryWriteStreamDynamic *out) {
int16 threadCount = 0;
Thread *th;
// Count the active threads
for (th = first(); th; th = next(th))
threadCount++;
// Store the thread count in the archive buffer
out->writeSint16LE(threadCount);
debugC(3, kDebugSaveload, "... threadCount = %d", threadCount);
// Iterate through the threads, archiving each
for (th = first(); th; th = next(th)) {
debugC(3, kDebugSaveload, "Loading ThreadID %d", getThreadID(th));
// Store the Thread's id number
out->writeSint16LE(getThreadID(th));
th->write(out);
}
}
//-------------------------------------------------------------------
// Cleanup the active threads
void ThreadList::cleanup() {
for (uint i = 0; i < kNumThreads; i++) {
delete _list[i];
_list[i] = nullptr;
}
}
//-------------------------------------------------------------------
// Place a thread back into the inactive list
void ThreadList::deleteThread(Thread *p) {
for (uint i = 0; i < kNumThreads; i++) {
if (_list[i] == p) {
_list[i] = nullptr;
}
}
}
void ThreadList::newThread(Thread *p, ThreadID id) {
if (_list[id])
error("Thread %d already exists", id);
_list[id] = p;
}
void ThreadList::newThread(Thread *p) {
for (uint i = 0; i < kNumThreads; i++) {
if (!_list[i]) {
_list[i] = p;
return;
}
}
error("ThreadList::newThread(): Too many threads");
}
//-------------------------------------------------------------------
// Return a pointer to the first active thread
Thread *ThreadList::first() {
for (uint i = 0; i < kNumThreads; i++)
if (_list[i])
return _list[i];
return nullptr;
}
Thread *ThreadList::next(Thread *thread) {
uint i;
for (i = 0; i < kNumThreads; i++)
if (_list[i] == thread)
break;
i++;
if (i >= kNumThreads)
return nullptr;
for (; i < kNumThreads; i++)
if (_list[i])
return _list[i];
return nullptr;
}
/* ===================================================================== *
Global thread list instantiation
* ===================================================================== */
// The thread list is instantiated like this in order to keep the
// constructor from being called until it is explicitly called with
// the overloaded new operator.
static uint8 threadListBuffer[sizeof(ThreadList)];
static ThreadList &threadList = *((ThreadList *)threadListBuffer);
/* ============================================================================ *
ThreadList management functions
* ============================================================================ */
//-------------------------------------------------------------------
// Initialize the SAGA thread list
void initSAGAThreads() {
// Simply call the Thread List default constructor
}
void saveSAGAThreads(Common::OutSaveFile *outS) {
debugC(2, kDebugSaveload, "Saving SAGA Threads");
outS->write("SAGA", 4);
CHUNK_BEGIN;
threadList.write(out);
CHUNK_END;
}
void loadSAGAThreads(Common::InSaveFile *in, int32 chunkSize) {
debugC(2, kDebugSaveload, "Loading SAGA Threads");
if (chunkSize == 0) {
return;
}
// Reconstruct stackList from archived data
threadList.read(in);
}
//-------------------------------------------------------------------
// Dispose of the active SAGA threads
void cleanupSAGAThreads() {
// Simply call the ThreadList cleanup() function
threadList.cleanup();
}
//-------------------------------------------------------------------
// Dispose of an active SAGA thread
void deleteThread(Thread *thread) {
threadList.deleteThread(thread);
}
void newThread(Thread *p, ThreadID id) {
threadList.newThread(p, id);
}
void newThread(Thread *thread) {
threadList.newThread(thread);
}
//-------------------------------------------------------------------
// Return the ID of the specified SAGA thread
ThreadID getThreadID(Thread *thread) {
return threadList.getThreadID(thread);
}
//-------------------------------------------------------------------
// Return a pointer to a SAGA thread, given a thread ID
Thread *getThreadAddress(ThreadID id) {
return threadList.getThreadAddress(id);
}
/* ============================================================================ *
Thread member functions
* ============================================================================ */
//-----------------------------------------------------------------------
// Thread constructor
Thread::Thread(uint16 segNum, uint16 segOff, scriptCallFrame &args) {
_codeSeg = scriptRes->loadIndexResource(segNum, "saga code segment");
// initialize the thread
_stackSize = kStackSize;
_flags = 0;
_returnVal = 0;
_programCounter.segment = segNum;
_programCounter.offset = segOff;
_threadArgs = args;
_stackBase = (byte *)malloc(_stackSize);
_stackPtr = _stackBase + _stackSize - initialStackFrameSize;
((uint16 *)_stackPtr)[0] = 0; // 0 args
((uint16 *)_stackPtr)[1] = 0; // dummy return address
((uint16 *)_stackPtr)[2] = 0; // dummy return address
_framePtr = _stackSize;
_valid = true;
if ((_codeSeg)[_programCounter.offset] != kOpEnter) {
//warning("SAGA failure: Invalid script entry point (export=%d) [segment=%d:%d]\n", lastExport, segNum, segOff);
_valid = false;
}
newThread(this);
}
Thread::Thread(Common::SeekableReadStream *stream, ThreadID id) {
int16 stackOffset;
_programCounter.segment = stream->readUint16LE();
_programCounter.offset = stream->readUint16LE();
_stackSize = stream->readSint16LE();
_flags = stream->readSint16LE();
_framePtr = stream->readSint16LE();
_returnVal = stream->readSint16LE();
_waitAlarm.read(stream);
stackOffset = stream->readSint16LE();
debugC(4, kDebugSaveload, "...... _stackSize = %d", _stackSize);
debugC(4, kDebugSaveload, "...... flags = %d", _flags);
debugC(4, kDebugSaveload, "...... _framePtr = %d", _framePtr);
debugC(4, kDebugSaveload, "...... _returnVal = %d", _returnVal);
debugC(4, kDebugSaveload, "...... stackOffset = %d", stackOffset);
_codeSeg = scriptRes->loadIndexResource(_programCounter.segment, "saga code segment");
_stackBase = (byte *)malloc(_stackSize);
_stackPtr = _stackBase + _stackSize - stackOffset;
stream->read(_stackPtr, stackOffset);
newThread(this, id);
}
//-----------------------------------------------------------------------
// Thread destructor
Thread::~Thread() {
// Clear extended bit if it was set
clearExtended();
// Free the thread's code segment
//RUnlockHandle((RHANDLE)_codeSeg);
// Deallocate the thread stack
free(_stackBase);
deleteThread(this);
}
//-----------------------------------------------------------------------
// Return the number of bytes need to archive this thread in an arhive
// buffer
int32 Thread::archiveSize() {
return sizeof(_programCounter)
+ sizeof(_stackSize)
+ sizeof(_flags)
+ sizeof(_framePtr)
+ sizeof(_returnVal)
+ sizeof(_waitAlarm)
+ sizeof(int16) // stack offset
+ (_stackBase + _stackSize) - _stackPtr;
}
void Thread::write(Common::MemoryWriteStreamDynamic *out) {
int16 stackOffset;
out->writeUint16LE(_programCounter.segment);
out->writeUint16LE(_programCounter.offset);
out->writeSint16LE(_stackSize);
out->writeSint16LE(_flags);
out->writeSint16LE(_framePtr);
out->writeSint16LE(_returnVal);
_waitAlarm.write(out);
warning("STUB: Thread::write: Pointer arithmetic");
stackOffset = (_stackBase + _stackSize) - _stackPtr;
out->writeSint16LE(stackOffset);
out->write(_stackPtr, stackOffset);
debugC(4, kDebugSaveload, "...... _stackSize = %d", _stackSize);
debugC(4, kDebugSaveload, "...... flags = %d", _flags);
debugC(4, kDebugSaveload, "...... _framePtr = %d", _framePtr);
debugC(4, kDebugSaveload, "...... _returnVal = %d", _returnVal);
debugC(4, kDebugSaveload, "...... stackOffset = %d", stackOffset);
}
//-----------------------------------------------------------------------
// Thread dispatcher
void Thread::dispatch() {
Thread *th,
*nextThread;
int numThreads = 0,
numExecute = 0,
numWaitDelay = 0,
numWaitFrames = 0,
numWaitSemi = 0,
numWaitOther = 0;
for (th = threadList.first(); th; th = threadList.next(th)) {
if (th->_flags & kTFWaiting) {
switch (th->_waitType) {
case kWaitDelay:
numWaitDelay++;
break;
case kWaitFrameDelay:
numWaitFrames++;
break;
case kWaitTagSemaphore:
numWaitSemi++;
break;
default:
numWaitOther++;
break;
}
} else numExecute++;
numThreads++;
}
debugC(9, kDebugScripts, "Threads:%d X:%d D:%d F:%d T:%d O:%d", numThreads, numExecute, numWaitDelay, numWaitFrames, numWaitSemi, numWaitOther);
for (th = threadList.first(); th; th = nextThread) {
nextThread = threadList.next(th);
if (th->_flags & (kTFFinished | kTFAborted)) {
delete th;
continue;
}
if (th->_flags & kTFWaiting) {
switch (th->_waitType) {
case kWaitDelay:
// Wake up the thread!
if (th->_waitAlarm.check())
th->_flags &= ~kTFWaiting;
break;
case kWaitFrameDelay:
if (th->_waitFrameAlarm.check())
th->_flags &= ~kTFWaiting;
break;
case kWaitTagSemaphore:
if (th->_waitParam->isExclusive() == false) {
th->_flags &= ~kTFWaiting;
th->_waitParam->setExclusive(true);
}
break;
default:
break;
}
}
do {
if (th->_flags & (kTFWaiting | kTFFinished | kTFAborted))
break;
if (th->interpret())
goto break_thread_loop;
} while (th->_flags & kTFSynchronous);
}
break_thread_loop:
;
}
//-----------------------------------------------------------------------
// Run scripts which are on the queue
void dispatchScripts() {
Thread::dispatch();
}
//-----------------------------------------------------------------------
// Run a script until finished
scriptResult Thread::run() {
int i = 4000;
while (i--) {
// If script stopped, then return
if (_flags & (kTFWaiting | kTFFinished | kTFAborted)) {
if (_flags & kTFFinished) return kScriptResultFinished;
if (_flags & kTFWaiting) return kScriptResultAsync;
return kScriptResultAborted;
// can't ever fall thru here...
}
// run the script some more...
interpret();
}
error("Thread timed out!\n");
}
//-----------------------------------------------------------------------
// Convert to extended thread
void Thread::setExtended() {
if (!(_flags & kTFExtended)) {
_flags |= kTFExtended;
extendedThreadLevel++;
}
}
//-----------------------------------------------------------------------
// Convert back to regular thread
void Thread::clearExtended() {
if (_flags & kTFExtended) {
_flags &= ~kTFExtended;
extendedThreadLevel--;
}
}
/* ============================================================================ *
Script Management functions
* ============================================================================ */
void initScripts() {
// Open the script resource group
scriptRes = scriptResFile->newContext(sagaID, "script resources");
if (scriptRes == nullptr)
error("Unable to open script resource file!\n");
// Load the data segment
dataSegment = scriptRes->loadResource(dataSegID, "saga data segment");
if (dataSegment == nullptr)
error("Unable to load the SAGA data segment");
dataSegSize = scriptRes->getSize(dataSegID, "saga data segment");
debugC(2, kDebugScripts, "dataSegment loaded at %p: size: %d", (void*)dataSegment, dataSegSize);
// Common::hexdump(dataSegment, dataSegSize);
exportSegment = scriptRes->loadResource(exportSegID, "saga export segment");
assert(exportSegment != nullptr);
// Common::hexdump(exportSegment, scriptRes->getSize(exportSegID, "saga export segment"));
exportCount = (scriptRes->getSize(exportSegID, "saga export segment") / sizeof(uint32)) + 1;
debugC(2, kDebugScripts, "exportSegment loaded at %p: size: %d, exportCount: %ld",
(void*)exportSegment, scriptRes->getSize(exportSegID, "saga export segment"), exportCount);
}
void cleanupScripts() {
if (exportSegment)
free(exportSegment);
if (dataSegment)
free(dataSegment);
if (scriptRes)
scriptResFile->disposeContext(scriptRes);
scriptRes = nullptr;
}
//-----------------------------------------------------------------------
// Load the SAGA data segment from the resource file
void initSAGADataSeg() {
// Load the data segment
scriptRes->seek(dataSegID);
scriptRes->read(dataSegment, dataSegSize);
}
void saveSAGADataSeg(Common::OutSaveFile *outS) {
debugC(2, kDebugSaveload, "Saving Data Segment");
outS->write("SDTA", 4);
CHUNK_BEGIN;
out->write(dataSegment, dataSegSize);
CHUNK_END;
}
void loadSAGADataSeg(Common::InSaveFile *in) {
in->read(dataSegment, dataSegSize);
}
//-----------------------------------------------------------------------
// Look up an entry in the SAGA export table
static bool lookupExport(
uint16 entry,
uint16 &segNum,
uint16 &segOff) {
uint32 segRef;
assert(entry > 0);
assert(entry <= exportCount);
segRef = READ_LE_INT32(exportSegment + 4 * entry - 2);
segOff = segRef >> 16,
segNum = segRef & 0x0000ffff;
lastExport = entry;
if (segNum > 1000)
error("SAGA failure: Bad data in export table entry #%d (see scripts.r)", entry);
return true;
}
//-----------------------------------------------------------------------
// Run a script to completion (or until it forks)
scriptResult runScript(uint16 exportEntryNum, scriptCallFrame &args) {
uint16 segNum,
segOff;
Thread *th;
scriptResult result;
Thread *saveThread = thisThread;
assert(exportEntryNum > 0);
lookupExport(exportEntryNum, segNum, segOff);
// Create a new thread
th = new Thread(segNum, segOff, args);
thisThread = th;
// FIXME: We should probably just use an error(), but this will work for mass debugging
if (th == nullptr) {
debugC(4, kDebugScripts, "Couldn't allocate memory for Thread(%d, %d)", segNum, segOff);
return kScriptResultNoScript;
} else if (!th->_valid) {
debugC(4, kDebugScripts, "Scripts: %d is not valid", lastExport);
return kScriptResultNoScript;
}
print_script_name((th->_codeSeg) + th->_programCounter.offset, objectName(segNum, segOff));
// Run the thread to completion
result = th->run();
args.returnVal = th->_returnVal;
// If the thread is not still running, then delete it
if (result != kScriptResultAsync) delete th;
// restore "thisThread" ptr.
thisThread = saveThread;
return result;
}
//-----------------------------------------------------------------------
// Run a class member function to completion (or until it forks)
scriptResult runMethod(
uint16 scriptClassID, // which script class
int16 bType, // builtin type
uint16 index, // object index
uint16 methodNum,
scriptCallFrame &args) {
uint16 segNum,
segOff;
uint16 *vTable;
Thread *th;
scriptResult result = kScriptResultNoScript;
Thread *saveThread = thisThread;
// For abstract classes, the object index is also the class
// index.
if (bType == kBuiltinAbstract)
index = scriptClassID;
lookupExport(scriptClassID, segNum, segOff);
// Get address of class function table
vTable = (uint16 *)
segmentAddress(segNum, segOff + methodNum * sizeof(uint32));
segNum = vTable[0];
segOff = vTable[1];
if (segNum == 0xffff) { // it's a CFUNC or NULL func
if (segOff == 0xffff) { // it's a NULL function
return kScriptResultNoScript;
} else { // It's a C function
int16 funcNum = segOff; // function number
int16 stack[1]; // dummy stack argument
C_Call *cfunc;
// Make sure the C function number is OK
assert(funcNum >= 0);
assert(funcNum < globalCFuncs.numEntries);
cfunc = globalCFuncs.table[funcNum];
// Build a temporary dummy thread
th = new Thread(0, 0, args);
thisThread = th;
if (th == nullptr)
return kScriptResultNoScript;
else if (!th->_valid)
return kScriptResultNoScript;
result = (scriptResult)cfunc(stack); // call the function
delete th;
}
} else {
// Create a new thread
th = new Thread(segNum, segOff, args);
thisThread = th;
if (th == nullptr) {
debugC(3, kDebugScripts, "Couldn't allocate memory for Thread(%d, %d)", segNum, segOff);
return kScriptResultNoScript;
} else if (!th->_valid) {
debugC(3, kDebugScripts, "Scripts: %d is not valid", lastExport);
return kScriptResultNoScript;
}
print_script_name((th->_codeSeg) + th->_programCounter.offset, objectName(bType, index));
// Put the object segment and ID onto the dummy stack frame
((uint16 *)th->_stackPtr)[3] = bType;
((uint16 *)th->_stackPtr)[4] = index;
// Run the thread to completion
result = th->run();
args.returnVal = th->_returnVal;
debugC(3, kDebugScripts, "return: %d", th->_returnVal);
if (result != kScriptResultAsync) delete th;
}
thisThread = saveThread; // restore "thisThread" ptr.
return result;
}
//-----------------------------------------------------------------------
// Run a class member function to completion (or until it forks)
scriptResult runObjectMethod(
ObjectID id,
uint16 methodNum,
scriptCallFrame &args) {
GameObject *obj;
obj = GameObject::objectAddress(id);
return runMethod(obj->scriptClass(),
kBuiltinTypeObject,
id,
methodNum,
args);
}
//-----------------------------------------------------------------------
// Run a class member function to completion (or until it forks)
scriptResult runTagMethod(
uint16 index, // tag number
uint16 methodNum,
scriptCallFrame &args) {
ActiveItemPtr aItem;
aItem = ActiveItem::activeItemAddress(index);
if (!aItem->_data.scriptClassID)
return kScriptResultNoScript;
return runMethod(aItem->_data.scriptClassID,
kBuiltinTypeTAG,
index,
methodNum,
args);
}
//-----------------------------------------------------------------------
// Wake up a thread unconditionally
void wakeUpThread(ThreadID id) {
if (id != NoThread) {
Thread *thread = getThreadAddress(id);
thread->_flags &= ~Thread::kTFWaiting;
}
}
void wakeUpThread(ThreadID id, int16 _returnVal) {
if (id != NoThread) {
Thread *thread = getThreadAddress(id);
if (thread->_flags & Thread::kTFExpectResult) {
WriteStatusF(8, "Result %d", _returnVal);
thread->_returnVal = _returnVal;
*(int16 *)thread->_stackPtr = _returnVal;
} else WriteStatusF(8, "Thread not expecting result!");
thread->_flags &= ~(Thread::kTFWaiting | Thread::kTFExpectResult);
}
}
} // end of namespace Saga2