aboutsummaryrefslogtreecommitdiff
path: root/engines/glk/frotz/processor_objects.cpp
blob: 13e8a1151814fcfc37093f739bb140a074d84478 (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
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
/* 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.
 *
 */

#include "glk/frotz/processor.h"

namespace Glk {
namespace Frotz {

#define MAX_OBJECT 2000

enum O1 {
	O1_PARENT          = 4,
	O1_SIBLING         = 5,
	O1_CHILD           = 6,
	O1_PROPERTY_OFFSET = 7,
	O1_SIZE            = 9
};

enum O4 {
	O4_PARENT          = 6,
	O4_SIBLING         = 8,
	O4_CHILD           = 10,
	O4_PROPERTY_OFFSET = 12,
	O4_SIZE            = 14
};

zword Processor::object_address(zword obj) {
    // Check object number
    if (obj > ((h_version <= V3) ? 255 : MAX_OBJECT)) {
        print_string("@Attempt to address illegal object ");
        print_num(obj);
        print_string(".  This is normally fatal.");
        new_line();
        runtimeError(ERR_ILL_OBJ);
    }

    // Return object address
    if (h_version <= V3)
        return h_objects + ((obj - 1) * O1_SIZE + 62);
    else
        return h_objects + ((obj - 1) * O4_SIZE + 126);
}

zword Processor::object_name(zword object) {
    zword obj_addr;
    zword name_addr;

    obj_addr = object_address(object);

    // The object name address is found at the start of the properties
    if (h_version <= V3)
        obj_addr += O1_PROPERTY_OFFSET;
    else
        obj_addr += O4_PROPERTY_OFFSET;

	LOW_WORD(obj_addr, name_addr);

    return name_addr;
}

zword Processor::first_property(zword obj) {
    zword prop_addr;
    zbyte size;

    // Fetch address of object name
    prop_addr = object_name (obj);

    // Get length of object name
	LOW_BYTE(prop_addr, size);

    // Add name length to pointer
    return prop_addr + 1 + 2 * size;
}

zword Processor::next_property(zword prop_addr) {
    zbyte value;

    // Load the current property id
	LOW_BYTE(prop_addr, value);
    prop_addr++;

    // Calculate the length of this property
    if (h_version <= V3)
        value >>= 5;
    else if (!(value & 0x80))
        value >>= 6;
    else {
		LOW_BYTE(prop_addr, value);
        value &= 0x3f;

        if (value == 0)
			// demanded by Spec 1.0
			value = 64;
    }

    // Add property length to current property pointer
    return prop_addr + value + 1;
}

void Processor::unlink_object(zword object) {
    zword obj_addr;
    zword parent_addr;
    zword sibling_addr;

    if (object == 0) {
        runtimeError(ERR_REMOVE_OBJECT_0);
        return;
    }

    obj_addr = object_address(object);

    if (h_version <= V3) {

        zbyte parent;
        zbyte younger_sibling;
        zbyte older_sibling;
        zbyte zero = 0;

        // Get parent of object, and return if no parent
        obj_addr += O1_PARENT;
		LOW_BYTE(obj_addr, parent);
        if (!parent)
            return;

        // Get (older) sibling of object and set both parent and sibling pointers to 0
		SET_BYTE(obj_addr, zero);
        obj_addr += O1_SIBLING - O1_PARENT;
		LOW_BYTE(obj_addr, older_sibling);
		SET_BYTE(obj_addr, zero);

        // Get first child of parent (the youngest sibling of the object)
        parent_addr = object_address(parent) + O1_CHILD;
		LOW_BYTE(parent_addr, younger_sibling);

        // Remove object from the list of siblings
		if (younger_sibling == object)
			SET_BYTE(parent_addr, older_sibling);
        else {
            do {
                sibling_addr = object_address(younger_sibling) + O1_SIBLING;
				LOW_BYTE(sibling_addr, younger_sibling);
            } while (younger_sibling != object);
			SET_BYTE(sibling_addr, older_sibling);
        }
    } else {
        zword parent;
        zword younger_sibling;
        zword older_sibling;
        zword zero = 0;

        // Get parent of object, and return if no parent
        obj_addr += O4_PARENT;
		LOW_WORD(obj_addr, parent);
        if (!parent)
            return;

        // Get (older) sibling of object and set both parent and sibling pointers to 0
		SET_WORD(obj_addr, zero);
        obj_addr += O4_SIBLING - O4_PARENT;
		LOW_WORD(obj_addr, older_sibling);
		SET_WORD(obj_addr, zero);

        // Get first child of parent (the youngest sibling of the object)
        parent_addr = object_address(parent) + O4_CHILD;
		LOW_WORD(parent_addr, younger_sibling);

        // Remove object from the list of siblings
		if (younger_sibling == object) {
			SET_WORD(parent_addr, older_sibling);
		} else {
            do {
                sibling_addr = object_address(younger_sibling) + O4_SIBLING;
				LOW_WORD(sibling_addr, younger_sibling);
            } while (younger_sibling != object);
			SET_WORD(sibling_addr, older_sibling);
        }
    }
}

void Processor::z_clear_attr() {
    zword obj_addr;
    zbyte value;

    if (_storyId == SHERLOCK)
        if (zargs[1] == 48)
            return;

    if (zargs[1] > ((h_version <= V3) ? 31 : 47))
        runtimeError(ERR_ILL_ATTR);

    // If we are monitoring attribute assignment display a short note
    if (_attribute_assignment) {
        stream_mssg_on();
        print_string("@clear_attr ");
        print_object(zargs[0]);
        print_string(" ");
        print_num(zargs[1]);
        stream_mssg_off();
    }

    if (zargs[0] == 0) {
        runtimeError(ERR_CLEAR_ATTR_0);
        return;
    }

    // Get attribute address
    obj_addr = object_address(zargs[0]) + zargs[1] / 8;

    // Clear attribute bit
	LOW_BYTE(obj_addr, value);
    value &= ~(0x80 >> (zargs[1] & 7));
	SET_BYTE(obj_addr, value);
}

void Processor::z_jin() {
    zword obj_addr;

    // If we are monitoring object locating display a short note
    if (_object_locating) {
        stream_mssg_on();
        print_string("@jin ");
        print_object(zargs[0]);
        print_string(" ");
        print_object(zargs[1]);
        stream_mssg_off();
    }

    if (zargs[0] == 0) {
        runtimeError(ERR_JIN_0);
        branch(0 == zargs[1]);
        return;
    }

    obj_addr = object_address(zargs[0]);

    if (h_version <= V3) {
        zbyte parent;

        // Get parent id from object
        obj_addr += O1_PARENT;
		LOW_BYTE(obj_addr, parent);

        // Branch if the parent is obj2
        branch(parent == zargs[1]);

    } else {
        zword parent;

        // Get parent id from object
        obj_addr += O4_PARENT;
		LOW_WORD(obj_addr, parent);

        // Branch if the parent is obj2
        branch(parent == zargs[1]);
    }
}

void Processor::z_get_child() {
    zword obj_addr;

    // If we are monitoring object locating display a short note
    if (_object_locating) {
        stream_mssg_on();
        print_string("@get_child ");
        print_object(zargs[0]);
        stream_mssg_off();
    }

    if (zargs[0] == 0) {
        runtimeError(ERR_GET_CHILD_0);
        store(0);
        branch(false);
        return;
    }

    obj_addr = object_address(zargs[0]);

    if (h_version <= V3) {
        zbyte child;

        // Get child id from object
        obj_addr += O1_CHILD;
		LOW_BYTE(obj_addr, child);

        // Store child id and branch
        store(child);
        branch(child);
    } else {
        zword child;

        // Get child id from object
        obj_addr += O4_CHILD;
		LOW_WORD(obj_addr, child);

        // Store child id and branch
        store(child);
        branch(child);
    }
}

void Processor::z_get_next_prop() {
    zword prop_addr;
    zbyte value;
    zbyte mask;

    if (zargs[0] == 0) {
        runtimeError(ERR_GET_NEXT_PROP_0);
        store(0);
        return;
    }

    // Property id is in bottom five (six) bits
    mask = (h_version <= V3) ? 0x1f : 0x3f;

    // Load address of first property
    prop_addr = first_property(zargs[0]);

    if (zargs[1] != 0) {
        // Scan down the property list
        do {
			LOW_BYTE(prop_addr, value);
            prop_addr = next_property(prop_addr);
        } while ((value & mask) > zargs[1]);

        // Exit if the property does not exist
        if ((value & mask) != zargs[1])
            runtimeError(ERR_NO_PROP);
    }

    // Return the property id
	LOW_BYTE(prop_addr, value);
    store((zword) (value & mask));
}

void Processor::z_get_parent() {
    zword obj_addr;

    // If we are monitoring object locating display a short note
    if (_object_locating) {
        stream_mssg_on();
        print_string("@get_parent ");
        print_object(zargs[0]);
        stream_mssg_off();
    }

    if (zargs[0] == 0) {
        runtimeError(ERR_GET_PARENT_0);
        store(0);
        return;
    }

    obj_addr = object_address(zargs[0]);

    if (h_version <= V3) {
        zbyte parent;

        // Get parent id from object
        obj_addr += O1_PARENT;
		LOW_BYTE(obj_addr, parent);

        // Store parent
        store(parent);

	} else {
        zword parent;

        // Get parent id from object
        obj_addr += O4_PARENT;
		LOW_WORD(obj_addr, parent);

        // Store parent
        store(parent);
    }
}

void Processor::z_get_prop() {
    zword prop_addr;
    zword wprop_val;
    zbyte bprop_val;
    zbyte value;
    zbyte mask;

    if (zargs[0] == 0) {
        runtimeError(ERR_GET_PROP_0);
        store(0);
        return;
    }

    // Property id is in bottom five (six) bits
    mask = (h_version <= V3) ? 0x1f : 0x3f;

    // Load address of first property
    prop_addr = first_property(zargs[0]);

    // Scan down the property list
    for (;;) {
		LOW_BYTE(prop_addr, value);
        if ((value & mask) <= zargs[1])
            break;
        prop_addr = next_property(prop_addr);
    }

    if ((value & mask) == zargs[1]) {
		// property found

        // Load property(byte or word sized)
        prop_addr++;

        if ((h_version <= V3 && !(value & 0xe0)) || (h_version >= V4 && !(value & 0xc0))) {
			LOW_BYTE(prop_addr, bprop_val);
            wprop_val = bprop_val;
		} else {
			LOW_WORD(prop_addr, wprop_val);
		}
    } else {
		// property not found

        // Load default value
        prop_addr = h_objects + 2 * (zargs[1] - 1);
		LOW_WORD(prop_addr, wprop_val);
    }

    // Store the property value
    store(wprop_val);
}

void Processor::z_get_prop_addr() {
    zword prop_addr;
    zbyte value;
    zbyte mask;

    if (zargs[0] == 0) {
        runtimeError(ERR_GET_PROP_ADDR_0);
        store(0);
        return;
    }

    if (_storyId == BEYOND_ZORK)
        if (zargs[0] > MAX_OBJECT)
            { store(0); return; }

    // Property id is in bottom five (six) bits
    mask = (h_version <= V3) ? 0x1f : 0x3f;

    // Load address of first property
    prop_addr = first_property(zargs[0]);

    // Scan down the property list
    for (;;) {
		LOW_BYTE(prop_addr, value);
        if ((value & mask) <= zargs[1])
            break;
        prop_addr = next_property(prop_addr);
    }

    // Calculate the property address or return zero
    if ((value & mask) == zargs[1]) {

        if (h_version >= V4 && (value & 0x80))
            prop_addr++;
        store((zword) (prop_addr + 1));

    } else {
		store(0);
	}
}

void Processor::z_get_prop_len() {
    zword addr;
    zbyte value;

    // Back up the property pointer to the property id
    addr = zargs[0] - 1;
	LOW_BYTE(addr, value);

    // Calculate length of property
    if (h_version <= V3)
        value = (value >> 5) + 1;
    else if (!(value & 0x80))
        value = (value >> 6) + 1;
    else {
        value &= 0x3f;

        if (value == 0)
			value = 64;        // demanded by Spec 1.0
    }

    // Store length of property
    store(value);
}

void Processor::z_get_sibling() {
    zword obj_addr;

    if (zargs[0] == 0) {
        runtimeError(ERR_GET_SIBLING_0);
        store(0);
        branch(false);
        return;
    }

    obj_addr = object_address(zargs[0]);

    if (h_version <= V3) {
        zbyte sibling;

        // Get sibling id from object
        obj_addr += O1_SIBLING;
		LOW_BYTE(obj_addr, sibling);

        // Store sibling and branch
        store(sibling);
        branch(sibling);

	} else {
        zword sibling;

        // Get sibling id from object
        obj_addr += O4_SIBLING;
		LOW_WORD(obj_addr, sibling);

        // Store sibling and branch
        store(sibling);
        branch(sibling);
    }
}

void Processor::z_insert_obj() {
    zword obj1 = zargs[0];
    zword obj2 = zargs[1];
    zword obj1_addr;
    zword obj2_addr;

    // If we are monitoring object movements display a short note
    if (_object_movement) {
        stream_mssg_on();
        print_string("@move_obj ");
        print_object(obj1);
        print_string(" ");
        print_object(obj2);
        stream_mssg_off();
    }

    if (obj1 == 0) {
        runtimeError(ERR_MOVE_OBJECT_0);
        return;
    }

    if (obj2 == 0) {
        runtimeError(ERR_MOVE_OBJECT_TO_0);
        return;
    }

    // Get addresses of both objects
    obj1_addr = object_address(obj1);
    obj2_addr = object_address(obj2);

    // Remove object 1 from current parent
    unlink_object(obj1);

    // Make object 1 first child of object 2
    if (h_version <= V3) {
        zbyte child;

        obj1_addr += O1_PARENT;
		SET_BYTE(obj1_addr, obj2);
        obj2_addr += O1_CHILD;
		LOW_BYTE(obj2_addr, child);
		SET_BYTE(obj2_addr, obj1);
        obj1_addr += O1_SIBLING - O1_PARENT;
		SET_BYTE(obj1_addr, child);

    } else {
        zword child;

        obj1_addr += O4_PARENT;
		SET_WORD(obj1_addr, obj2);
        obj2_addr += O4_CHILD;
		LOW_WORD(obj2_addr, child);
		SET_WORD(obj2_addr, obj1);
        obj1_addr += O4_SIBLING - O4_PARENT;
		SET_WORD(obj1_addr, child);
    }
}

void Processor::z_put_prop() {
    zword prop_addr;
    zword value;
    zbyte mask;

    if (zargs[0] == 0) {
        runtimeError(ERR_PUT_PROP_0);
        return;
    }

    // Property id is in bottom five or six bits
    mask = (h_version <= V3) ? 0x1f : 0x3f;

    // Load address of first property
    prop_addr = first_property(zargs[0]);

    // Scan down the property list
    for (;;) {
		LOW_BYTE(prop_addr, value);
        if ((value & mask) <= zargs[1])
            break;

        prop_addr = next_property(prop_addr);
    }

    // Exit if the property does not exist
    if ((value & mask) != zargs[1])
        runtimeError(ERR_NO_PROP);

    // Store the new property value (byte or word sized)
    prop_addr++;

    if ((h_version <= V3 && !(value & 0xe0)) || (h_version >= V4 && !(value & 0xc0))) {
        zbyte v = zargs[2];
		SET_BYTE(prop_addr, v);
    } else {
        zword v = zargs[2];
		SET_WORD(prop_addr, v);
    }
}

void Processor::z_remove_obj() {
    // If we are monitoring object movements display a short note
    if (_object_movement) {
        stream_mssg_on();
        print_string("@remove_obj ");
        print_object(zargs[0]);
        stream_mssg_off();
    }

    // Call unlink_object to do the job
    unlink_object(zargs[0]);
}

void Processor::z_set_attr() {
    zword obj_addr;
    zbyte value;

    if (_storyId == SHERLOCK)
        if (zargs[1] == 48)
            return;

    if (zargs[1] > ((h_version <= V3) ? 31 : 47))
        runtimeError(ERR_ILL_ATTR);

    // If we are monitoring attribute assignment display a short note
    if (_attribute_assignment) {
        stream_mssg_on();
        print_string("@set_attr ");
        print_object(zargs[0]);
        print_string(" ");
        print_num(zargs[1]);
        stream_mssg_off();
    }

    if (zargs[0] == 0) {
        runtimeError(ERR_SET_ATTR_0);
        return;
    }

    // Get attribute address
    obj_addr = object_address(zargs[0]) + zargs[1] / 8;

    // Load attribute byte
	LOW_BYTE(obj_addr, value);

    // Set attribute bit
    value |= 0x80 >> (zargs[1] & 7);

    // Store attribute byte
	SET_BYTE(obj_addr, value);
}

void Processor::z_test_attr() {
    zword obj_addr;
    zbyte value;

    if (zargs[1] > ((h_version <= V3) ? 31 : 47))
        runtimeError(ERR_ILL_ATTR);

    // If we are monitoring attribute testing display a short note
    if (_attribute_testing) {
        stream_mssg_on();
        print_string("@test_attr ");
        print_object(zargs[0]);
        print_string(" ");
        print_num(zargs[1]);
        stream_mssg_off();
    }

    if (zargs[0] == 0) {
        runtimeError(ERR_TEST_ATTR_0);
        branch(false);
        return;
    }

    // Get attribute address
    obj_addr = object_address(zargs[0]) + zargs[1] / 8;

    // Load attribute byte
	LOW_BYTE(obj_addr, value);

    // Test attribute
    branch(value & (0x80 >> (zargs[1] & 7)));
}

} // End of namespace Scott
} // End of namespace Glk