aboutsummaryrefslogtreecommitdiff
path: root/engines/sci/engine/segment.cpp
blob: 2bb77c707af3e20d75f7e6f696972fdb903fd45b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
/* 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 2
 * 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, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * $URL$
 * $Id$
 *
 */

#include "common/endian.h"

#include "sci/sci.h"
#include "sci/engine/kernel.h"
#include "sci/engine/features.h"
#include "sci/engine/object.h"
#include "sci/engine/script.h"	// for SCI_OBJ_EXPORTS and SCI_OBJ_SYNONYMS
#include "sci/engine/segment.h"
#include "sci/engine/seg_manager.h"
#include "sci/engine/state.h"

namespace Sci {

//#define GC_DEBUG // Debug garbage collection
//#define GC_DEBUG_VERBOSE // Debug garbage verbosely

SegmentObj *SegmentObj::createSegmentObj(SegmentType type) {
	SegmentObj *mem = 0;
	switch (type) {
	case SEG_TYPE_SCRIPT:
		mem = new Script();
		break;
	case SEG_TYPE_CLONES:
		mem = new CloneTable();
		break;
	case SEG_TYPE_LOCALS:
		mem = new LocalVariables();
		break;
	case SEG_TYPE_STACK:
		mem = new DataStack();
		break;
	case SEG_TYPE_HUNK:
		mem = new HunkTable();
		break;
	case SEG_TYPE_LISTS:
		mem = new ListTable();
		break;
	case SEG_TYPE_NODES:
		mem = new NodeTable();
		break;
	case SEG_TYPE_DYNMEM:
		mem = new DynMem();
		break;
#ifdef ENABLE_SCI32
	case SEG_TYPE_ARRAY:
		mem = new ArrayTable();
		break;
	case SEG_TYPE_STRING:
		mem = new StringTable();
		break;
#endif
	default:
		error("Unknown SegmentObj type %d", type);
		break;
	}

	assert(mem);
	assert(mem->_type == type);
	return mem;
}

SegmentRef SegmentObj::dereference(reg_t pointer) {
	error("Error: Trying to dereference pointer %04x:%04x to inappropriate segment",
		          PRINT_REG(pointer));
	return SegmentRef();
}

//-------------------- clones --------------------

Common::Array<reg_t> CloneTable::listAllOutgoingReferences(reg_t addr) const {
	Common::Array<reg_t> tmp;
//	assert(addr.segment == _segId);

	if (!isValidEntry(addr.offset)) {
		error("Unexpected request for outgoing references from clone at %04x:%04x", PRINT_REG(addr));
	}

	const Clone *clone = &(_table[addr.offset]);

	// Emit all member variables (including references to the 'super' delegate)
	for (uint i = 0; i < clone->getVarCount(); i++)
		tmp.push_back(clone->getVariable(i));

	// Note that this also includes the 'base' object, which is part of the script and therefore also emits the locals.
	tmp.push_back(clone->getPos());
	//debugC(kDebugLevelGC, "[GC] Reporting clone-pos %04x:%04x", PRINT_REG(clone->pos));

	return tmp;
}

void CloneTable::freeAtAddress(SegManager *segMan, reg_t addr) {
#ifdef GC_DEBUG
	Object *victim_obj = &(_table[addr.offset]);

	if (!(victim_obj->_flags & OBJECT_FLAG_FREED))
		warning("[GC] Clone %04x:%04x not reachable and not freed (freeing now)", PRINT_REG(addr));
#ifdef GC_DEBUG_VERBOSE
	else
		warning("[GC-DEBUG] Clone %04x:%04x: Freeing", PRINT_REG(addr));

	warning("[GC] Clone had pos %04x:%04x", PRINT_REG(victim_obj->pos));
#endif
#endif

	freeEntry(addr.offset);
}


//-------------------- locals --------------------

SegmentRef LocalVariables::dereference(reg_t pointer) {
	SegmentRef ret;
	ret.isRaw = false;	// reg_t based data!
	ret.maxSize = (_locals.size() - pointer.offset / 2) * 2;

	if (pointer.offset & 1) {
		ret.maxSize -= 1;
		ret.skipByte = true;
	}

	if (ret.maxSize > 0) {
		ret.reg = &_locals[pointer.offset / 2];
	} else {
		if ((g_sci->getEngineState()->currentRoomNumber() == 660 || g_sci->getEngineState()->currentRoomNumber() == 660)
			&& g_sci->getGameId() == GID_LAURABOW2) {
			// Happens in two places during the intro of LB2CD, both from kMemory(peek):
			// - room 160: Heap 160 has 83 local variables (0-82), and the game
			//   asks for variables at indices 83 - 90 too.
			// - room 220: Heap 220 has 114 local variables (0-113), and the
			//   game asks for variables at indices 114-120 too.
		} else {
			error("LocalVariables::dereference: Offset at end or out of bounds %04x:%04x", PRINT_REG(pointer));
		}
		ret.reg = 0;
	}
	return ret;
}

reg_t LocalVariables::findCanonicAddress(SegManager *segMan, reg_t addr) const {
	// Reference the owning script
	SegmentId owner_seg = segMan->getScriptSegment(script_id);
	assert(owner_seg > 0);
	return make_reg(owner_seg, 0);
}

Common::Array<reg_t> LocalVariables::listAllOutgoingReferences(reg_t addr) const {
	Common::Array<reg_t> tmp;
	for (uint i = 0; i < _locals.size(); i++)
		tmp.push_back(_locals[i]);

	return tmp;
}


//-------------------- stack --------------------

SegmentRef DataStack::dereference(reg_t pointer) {
	SegmentRef ret;
	ret.isRaw = false;	// reg_t based data!
	ret.maxSize = (_capacity - pointer.offset / 2) * 2;

	if (pointer.offset & 1) {
		ret.maxSize -= 1;
		ret.skipByte = true;
	}

	ret.reg = &_entries[pointer.offset / 2];
	return ret;
}

Common::Array<reg_t> DataStack::listAllOutgoingReferences(reg_t object) const {
	Common::Array<reg_t> tmp;
	for (int i = 0; i < _capacity; i++)
		tmp.push_back(_entries[i]);

	return tmp;
}

//-------------------- lists --------------------

Common::Array<reg_t> ListTable::listAllOutgoingReferences(reg_t addr) const {
	Common::Array<reg_t> tmp;
	if (!isValidEntry(addr.offset)) {
		error("Invalid list referenced for outgoing references: %04x:%04x", PRINT_REG(addr));
	}

	const List *list = &(_table[addr.offset]);

	tmp.push_back(list->first);
	tmp.push_back(list->last);
	// We could probably get away with just one of them, but
	// let's be conservative here.

	return tmp;
}

//-------------------- nodes --------------------

Common::Array<reg_t> NodeTable::listAllOutgoingReferences(reg_t addr) const {
	Common::Array<reg_t> tmp;
	if (!isValidEntry(addr.offset)) {
		error("Invalid node referenced for outgoing references: %04x:%04x", PRINT_REG(addr));
	}
	const Node *node = &(_table[addr.offset]);

	// We need all four here. Can't just stick with 'pred' OR 'succ' because node operations allow us
	// to walk around from any given node
	tmp.push_back(node->pred);
	tmp.push_back(node->succ);
	tmp.push_back(node->key);
	tmp.push_back(node->value);

	return tmp;
}

//-------------------- dynamic memory --------------------

SegmentRef DynMem::dereference(reg_t pointer) {
	SegmentRef ret;
	ret.isRaw = true;
	ret.maxSize = _size - pointer.offset;
	ret.raw = _buf + pointer.offset;
	return ret;
}

#ifdef ENABLE_SCI32

SegmentRef ArrayTable::dereference(reg_t pointer) {
	SegmentRef ret;
	ret.isRaw = false;
	ret.maxSize = _table[pointer.offset].getSize() * 2;
	ret.reg = _table[pointer.offset].getRawData();
	return ret;
}

void ArrayTable::freeAtAddress(SegManager *segMan, reg_t sub_addr) { 
	_table[sub_addr.offset].destroy();
	freeEntry(sub_addr.offset);
}

Common::Array<reg_t> ArrayTable::listAllOutgoingReferences(reg_t addr) const {
	Common::Array<reg_t> tmp;
	if (!isValidEntry(addr.offset)) {
		error("Invalid array referenced for outgoing references: %04x:%04x", PRINT_REG(addr));
	}

	const SciArray<reg_t> *array = &(_table[addr.offset]);

	for (uint32 i = 0; i < array->getSize(); i++) {
		reg_t value = array->getValue(i);
		if (value.segment != 0)
			tmp.push_back(value);
	}

	return tmp;
}

Common::String SciString::toString() const {
	if (_type != 3)
		error("SciString::toString(): Array is not a string");

	Common::String string;
	for (uint32 i = 0; i < _size && _data[i] != 0; i++)
		string += _data[i];

	return string;
}

void SciString::fromString(const Common::String &string) {
	if (_type != 3)
		error("SciString::fromString(): Array is not a string");

	if (string.size() > _size)
		setSize(string.size());

	for (uint32 i = 0; i < string.size(); i++)
		_data[i] = string[i];
}

SegmentRef StringTable::dereference(reg_t pointer) {
	SegmentRef ret;
	ret.isRaw = true;
	ret.maxSize = _table[pointer.offset].getSize();
	ret.raw = (byte*)_table[pointer.offset].getRawData();
	return ret;
}

#endif

} // End of namespace Sci