aboutsummaryrefslogtreecommitdiff
path: root/saga/script.cpp
blob: a449ac6934e243681e555e77c2f893b2a64e243b (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
/* ScummVM - Scumm Interpreter
 * Copyright (C) 2004 The ScummVM project
 *
 * The ReInherit Engine is (C)2000-2003 by Daniel Balsom.
 *
 * 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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 *
 * $Header$
 *
 */

// Scripting module: Script resource handling functions
#include "saga.h"
#include "reinherit.h"

#include "yslib.h"

#include "rscfile_mod.h"
#include "game_mod.h"
#include "text_mod.h"
#include "console_mod.h"
#include "cvar_mod.h"

#include "script_mod.h"
#include "script.h"
#include "sstack.h"
#include "sthread.h"

namespace Saga {

R_SCRIPT_MODULE ScriptModule;

int SCRIPT_Register() {
	CVAR_RegisterFunc(CF_script_info, "script_info", NULL, R_CVAR_NONE, 0, 0);
	CVAR_RegisterFunc(CF_script_exec, "script_exec", "<Script number>", R_CVAR_NONE, 1, 1);
	CVAR_RegisterFunc(CF_script_togglestep, "script_togglestep", NULL, R_CVAR_NONE, 0, 0);

	return R_SUCCESS;
}

// Initializes the scripting module.
// Loads script resource look-up table, initializes script data system
int SCRIPT_Init() {
	R_RSCFILE_CONTEXT *s_lut_ctxt;
	byte *rsc_ptr;
	size_t rsc_len;
	int prevTell;
	int result;
	int i, j;

	debug(0, "Initializing scripting subsystem.");
	// Load script resource file context
	result = GAME_GetFileContext(&ScriptModule.script_ctxt, R_GAME_SCRIPTFILE, 0);
	if (result != R_SUCCESS) {
		warning("Couldn't get script file context");
		return R_FAILURE;
	}

	// Load script LUT resource
	result = GAME_GetFileContext(&s_lut_ctxt, R_GAME_RESOURCEFILE, 0);
	if (result != R_SUCCESS) {
		warning("Couldn't get resource file context");
		return R_FAILURE;
	}

	result = RSC_LoadResource(s_lut_ctxt, ITE_SCRIPT_LUT, &rsc_ptr, &rsc_len);
	if (result != R_SUCCESS) {
		warning("Error: Couldn't load script resource look-up table");
		return R_FAILURE;
	}

	// Create logical script LUT from resource
	if (rsc_len % R_S_LUT_ENTRYLEN_ITECD == 0) {
		ScriptModule.script_lut_entrylen = R_S_LUT_ENTRYLEN_ITECD;
	} else if (rsc_len % R_S_LUT_ENTRYLEN_ITEDISK == 0) {
		ScriptModule.script_lut_entrylen = R_S_LUT_ENTRYLEN_ITEDISK;
	} else {
		warning("Error: Invalid script lookup table length");
		return R_FAILURE;
	}

	// Calculate number of entries
	ScriptModule.script_lut_max = rsc_len / ScriptModule.script_lut_entrylen;

	// Allocate space for logical LUT
	ScriptModule.script_lut = (R_SCRIPT_LUT_ENTRY *)malloc(ScriptModule.script_lut_max * sizeof(R_SCRIPT_LUT_ENTRY));
	if (ScriptModule.script_lut == NULL) {
		warning("Error: Couldn't allocate memory for script resource look-up table");
		return R_MEM;
	}

	// Convert LUT resource to logical LUT
	MemoryReadStream *readS = new MemoryReadStream(rsc_ptr, rsc_len);
	for (i = 0; i < ScriptModule.script_lut_max; i++) {
		prevTell = readS->pos();
		ScriptModule.script_lut[i].script_rn = readS->readUint16LE();
		ScriptModule.script_lut[i].diag_list_rn = readS->readUint16LE();
		ScriptModule.script_lut[i].voice_lut_rn = readS->readUint16LE();
		// Skip the unused portion of the structure
		for (j = readS->pos(); j < prevTell + ScriptModule.script_lut_entrylen; j++)
			readS->readByte();
	}

	RSC_FreeResource(rsc_ptr);

	// Any voice lookup table resources present?
	for (i = 0; i < ScriptModule.script_lut_max; i++) {
		if (ScriptModule.script_lut[i].voice_lut_rn) {
			ScriptModule.voice_lut_present = 1;
			break;
		}
	}

	// Initialize script submodules
	ScriptModule.thread_list = ys_dll_create();

	if (SDATA_Init() != R_SUCCESS) {
		free(ScriptModule.script_lut);
		return R_FAILURE;
	}

	ScriptModule.initialized = 1;
	return R_SUCCESS;
}

// Shut down script module gracefully; free all allocated module resources
int SCRIPT_Shutdown() {
	YS_DL_NODE *thread_node;
	R_SCRIPT_THREAD *thread;

	if (!ScriptModule.initialized) {
		return R_FAILURE;
	}

	debug(0, "Shutting down scripting subsystem.");

	// Free script lookup table
	free(ScriptModule.script_lut);

	// Stop all threads and destroy them

	for (thread_node = ys_dll_head(ScriptModule.thread_list); thread_node != NULL;
				thread_node = ys_dll_next(thread_node)) {
		thread = (R_SCRIPT_THREAD *)ys_dll_get_data(thread_node);
		STHREAD_Destroy(thread);
	}

	ScriptModule.initialized = 0;

	return R_SUCCESS;
}

// Loads a script; including script bytecode and dialogue list 
int SCRIPT_Load(int script_num) {
	R_SCRIPTDATA *script_data;
	byte *bytecode_p;
	size_t bytecode_len;
	uint32 scriptl_rn;
	byte *diagl_p;
	size_t diagl_len;
	uint32 diagl_rn;
	byte *voicelut_p;
	size_t voicelut_len;
	uint32 voicelut_rn;
	int result;

	if (GAME_GetGameType() == R_GAMETYPE_IHNM) {
		return R_SUCCESS;
	}

	// Validate script number
	if ((script_num < 0) || (script_num > ScriptModule.script_lut_max)) {
		warning("SCRIPT_Load(): Invalid script number");
		return R_FAILURE;
	}

	// Release old script data if present
	SCRIPT_Free();

	// Initialize script data structure
	debug(0, "Loading script data for script #%d", script_num);

	script_data = (R_SCRIPTDATA *)malloc(sizeof *script_data);
	if (script_data == NULL) {
		warning("Memory allocation failed");
		return R_MEM;
	}

	script_data->loaded = 0;

	// Initialize script pointers
	script_data->diag = NULL;
	script_data->bytecode = NULL;
	script_data->voice = NULL;

	// Load script bytecode
	scriptl_rn = ScriptModule.script_lut[script_num].script_rn;

	result = RSC_LoadResource(ScriptModule.script_ctxt, scriptl_rn, &bytecode_p, &bytecode_len);
	if (result != R_SUCCESS) {
		warning("Error loading script bytecode resource");
		free(script_data);
		return R_FAILURE;
	}

	script_data->bytecode = SCRIPT_LoadBytecode(bytecode_p, bytecode_len);

	if (script_data->bytecode == NULL) {
		warning("Error interpreting script bytecode resource");
		free(script_data);
		RSC_FreeResource(bytecode_p);
		return R_FAILURE;
	}

	// Load script dialogue list
	diagl_rn = ScriptModule.script_lut[script_num].diag_list_rn;

	// Load dialogue list resource
	result = RSC_LoadResource(ScriptModule.script_ctxt, diagl_rn, &diagl_p, &diagl_len);
	if (result != R_SUCCESS) {
		warning("Error loading dialogue list resource");
		free(script_data);
		RSC_FreeResource(bytecode_p);
		return R_FAILURE;
	}

	// Convert dialogue list resource to logical dialogue list
	script_data->diag = SCRIPT_LoadDialogue(diagl_p, diagl_len);
	if (script_data->diag == NULL) {
		warning("Error interpreting dialogue list resource");
		free(script_data);
		RSC_FreeResource(bytecode_p);
		RSC_FreeResource(diagl_p);
		return R_FAILURE;
	}

	// Load voice resource lookup table
	if (ScriptModule.voice_lut_present) {
		voicelut_rn = ScriptModule.script_lut[script_num].voice_lut_rn;

		// Load voice LUT resource
		result = RSC_LoadResource(ScriptModule.script_ctxt, voicelut_rn, &voicelut_p, &voicelut_len);
		if (result != R_SUCCESS) {
			warning("Error loading voice LUT resource");
			free(script_data);
			RSC_FreeResource(bytecode_p);
			RSC_FreeResource(diagl_p);
			return R_FAILURE;
		}

		// Convert voice LUT resource to logical voice LUT
		script_data->voice = SCRIPT_LoadVoiceLUT(voicelut_p, voicelut_len, script_data);
		if (script_data->voice == NULL) {
			warning("Error interpreting voice LUT resource");
			free(script_data);
			RSC_FreeResource(bytecode_p);
			RSC_FreeResource(diagl_p);
			RSC_FreeResource(voicelut_p);
			return R_FAILURE;
		}
	}

	// Finish initialization
	script_data->loaded = 1;
	ScriptModule.current_script = script_data;

	return R_SUCCESS;
}

// Frees all resources associated with current script.
int SCRIPT_Free() {
	if (ScriptModule.current_script == NULL) {
		return R_FAILURE;
	}

	if (!ScriptModule.current_script->loaded) {
		return R_FAILURE;
	}

	debug(0, "Releasing script data.");

	// Finish initialization
	if (ScriptModule.current_script->diag != NULL) {
		free(ScriptModule.current_script->diag->str);
		free(ScriptModule.current_script->diag->str_off);
	}
	free(ScriptModule.current_script->diag);

	if (ScriptModule.current_script->bytecode != NULL) {
		free(ScriptModule.current_script->bytecode->entrypoints);
		RSC_FreeResource(ScriptModule.current_script->bytecode->bytecode_p);
	}

	free(ScriptModule.current_script->bytecode);

	if (ScriptModule.voice_lut_present) {
		free(ScriptModule.current_script->voice->voices);
		free(ScriptModule.current_script->voice);
	}

	free(ScriptModule.current_script);

	ScriptModule.current_script = NULL;

	return R_SUCCESS;
}

// Reads the entrypoint table from a script bytecode resource in memory. 
// Returns NULL on failure.
R_SCRIPT_BYTECODE *SCRIPT_LoadBytecode(byte *bytecode_p, size_t bytecode_len) {
	R_PROC_TBLENTRY *bc_ep_tbl = NULL;
	R_SCRIPT_BYTECODE *bc_new_data = NULL;

	unsigned long n_entrypoints; // Number of entrypoints
	size_t ep_tbl_offset; // Offset of bytecode entrypoint table
	unsigned long i;

	debug(0, "Loading script bytecode...");

	MemoryReadStream *readS = new MemoryReadStream(bytecode_p, bytecode_len);

	// The first two uint32 values are the number of entrypoints, and the
	// offset to the entrypoint table, respectively.
	n_entrypoints = readS->readUint32LE();
	ep_tbl_offset = readS->readUint32LE();

	// Check that the entrypoint table offset is valid.
	if ((bytecode_len - ep_tbl_offset) < (n_entrypoints * R_SCRIPT_TBLENTRY_LEN)) {
		warning("Invalid table offset");
		return NULL;
	}

	if (n_entrypoints > R_SCRIPT_MAX) {
		warning("Script limit exceeded");
		return NULL;
	}

	// Allocate a new bytecode resource information structure and table of
	// entrypoints

	bc_new_data = (R_SCRIPT_BYTECODE *)malloc(sizeof *bc_new_data);
	if (bc_new_data == NULL) {
		warning("Memory allocation failure loading script bytecode");
		return NULL;
	}

	bc_ep_tbl = (R_PROC_TBLENTRY *)malloc(n_entrypoints * sizeof *bc_ep_tbl);
	if (bc_ep_tbl == NULL) {
		warning("Memory allocation failure creating script entrypoint table");
		free(bc_new_data);
		return NULL;
	}

	// Read in the entrypoint table

	while (readS->pos() < ep_tbl_offset)
		readS->readByte();

	for (i = 0; i < n_entrypoints; i++) {
		// First uint16 is the offset of the entrypoint name from the start
		// of the bytecode resource, second uint16 is the offset of the 
		// bytecode itself for said entrypoint
		bc_ep_tbl[i].name_offset = readS->readUint16LE();
		bc_ep_tbl[i].offset = readS->readUint16LE();

		// Perform a simple range check on offset values
		if ((bc_ep_tbl[i].name_offset > bytecode_len) || (bc_ep_tbl[i].offset > bytecode_len)) {
			warning("Invalid offset encountered in script entrypoint table");
			free(bc_new_data);
			free(bc_ep_tbl);
			return NULL;
		}
	}

	bc_new_data->bytecode_p = (byte *) bytecode_p;
	bc_new_data->bytecode_len = bytecode_len;

	bc_new_data->n_entrypoints = n_entrypoints;
	bc_new_data->entrypoints = bc_ep_tbl;
	bc_new_data->ep_tbl_offset = ep_tbl_offset;

	return bc_new_data;
}

// Reads a logical dialogue list from a dialogue list resource in memory.
// Returns NULL on failure.
R_DIALOGUE_LIST *SCRIPT_LoadDialogue(const byte *dialogue_p, size_t dialogue_len) {
	R_DIALOGUE_LIST *dialogue_list;
	uint16 n_dialogue;
	uint16 i;
	size_t offset;

	debug(0, "Loading dialogue list...");

	// Allocate dialogue list structure
	dialogue_list = (R_DIALOGUE_LIST *)malloc(sizeof *dialogue_list);
	if (dialogue_list == NULL) {
		return NULL;
	}

	MemoryReadStream *readS = new MemoryReadStream(dialogue_p, dialogue_len);

	// First uint16 is the offset of the first string
	offset = readS->readUint16LE();
	if (offset > dialogue_len) {
		warning("Error, invalid string offset");
		return NULL;
	}

	// Calculate table length
	n_dialogue = offset / 2;
	dialogue_list->n_dialogue = n_dialogue;

	// Allocate table of string pointers
	dialogue_list->str = (const char **)malloc(n_dialogue * sizeof(const char *));
	if (dialogue_list->str == NULL) {
		free(dialogue_list);
		return NULL;
	}

	// Allocate table of string offsets
	dialogue_list->str_off = (size_t *)malloc(n_dialogue * sizeof(size_t));
	if (dialogue_list->str_off == NULL) {
		free(dialogue_list->str);
		free(dialogue_list);
		return NULL;
	}

	// Read in tables from dialogue list resource
	readS->seek(0);
	for (i = 0; i < n_dialogue; i++) {
		offset = readS->readUint16LE();
		if (offset > dialogue_len) {
			warning("Error, invalid string offset");
			free(dialogue_list->str);
			free(dialogue_list->str_off);
			free(dialogue_list);
			return NULL;
		}
		dialogue_list->str[i] = (const char *)dialogue_p + offset;
		dialogue_list->str_off[i] = offset;
	}

	return dialogue_list;
}

// Reads a logical voice LUT from a voice LUT resource in memory.
// Returns NULL on failure.
R_VOICE_LUT *SCRIPT_LoadVoiceLUT(const byte *voicelut_p, size_t voicelut_len, R_SCRIPTDATA *script) {
	R_VOICE_LUT *voice_lut;

	uint16 n_voices;
	uint16 i;

	voice_lut = (R_VOICE_LUT *)malloc(sizeof *voice_lut);
	if (voice_lut == NULL) {
		return NULL;
	}

	n_voices = voicelut_len / 2;
	if (n_voices != script->diag->n_dialogue) {
		warning("Error: Voice LUT entries do not match dialogue entries");
		return NULL;
	}

	voice_lut->voices = (int *)malloc(n_voices * sizeof *voice_lut->voices);
	if (voice_lut->voices == NULL) {

		return NULL;
	}

	MemoryReadStream *readS = new MemoryReadStream(voicelut_p, voicelut_len);

	for (i = 0; i < n_voices; i++) {
		voice_lut->voices[i] = readS->readUint16LE();
	}

	return voice_lut;
}

void CF_script_info(int argc, char *argv[]) {
	uint32 n_entrypoints;
	uint32 i;
	char *name_ptr;

	if (ScriptModule.current_script == NULL) {
		return;
	}

	if (!ScriptModule.current_script->loaded) {
		return;
	}

	n_entrypoints = ScriptModule.current_script->bytecode->n_entrypoints;

	CON_Print("Current script contains %d entrypoints:", n_entrypoints);

	for (i = 0; i < n_entrypoints; i++) {
		name_ptr = (char *)ScriptModule.current_script->bytecode->bytecode_p +
							ScriptModule.current_script->bytecode->entrypoints[i].name_offset;
		CON_Print("%lu: %s", i, name_ptr);
	}
}

void CF_script_exec(int argc, char *argv[]) {
	uint16 ep_num;

	if (argc < 1) {
		return;
	}

	ep_num = atoi(argv[0]);

	if (ScriptModule.dbg_thread == NULL) {
		CON_Print("Creating debug thread...");
		ScriptModule.dbg_thread = STHREAD_Create();
		if (ScriptModule.dbg_thread == NULL) {
			CON_Print("Thread creation failed.");
			return;
		}
	}

	if (ep_num >= ScriptModule.current_script->bytecode->n_entrypoints) {
		CON_Print("Invalid entrypoint.");
		return;
	}

	STHREAD_Execute(ScriptModule.dbg_thread, ep_num);
}

void CF_script_togglestep(int argc, char *argv[]) {
	ScriptModule.dbg_singlestep = !ScriptModule.dbg_singlestep;
}

} // End of namespace Saga