aboutsummaryrefslogtreecommitdiff
path: root/engines/sci/engine/kfile.cpp
blob: ee80af6a72c49bff7f7f54011d46d018e72c4d1a (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
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
/* 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/archive.h"
#include "common/file.h"
#include "common/str.h"
#include "common/savefile.h"

#include "sci/sci.h"
#include "sci/engine/state.h"
#include "sci/engine/kernel.h"
#include "sci/engine/savegame.h"

namespace Sci {


/*
 * Note on how file I/O is implemented: In ScummVM, one can not create/write
 * arbitrary data files, simply because many of our target platforms do not
 * support this. The only files on can create are savestates. But SCI has an
 * opcode to create and write to seemingly 'arbitrary' files.
 * To implement that opcode, we combine the SaveFileManager with regular file
 * code, similarly to how the SCUMM HE engine does it.
 *
 * To handle opening a file called "foobar", what we do is this: First, we
 * create an 'augmented file name', by prepending the game target and a dash,
 * so if we running game target sq1vga, the name becomes "sq1vga-foobar". 
 * Next, we check if such a file is known to the SaveFileManager. If so, we
 * we use that for reading/writing, delete it, whatever.
 *
 * If no such file is present but we were only asked to *read* the file,
 * we fallback to looking for a regular file called "foobar", and open that
 * for reading only.
 * 
 * There are some caveats to this: First off, SCI apparently has no way
 * to signal that a file is supposed to be opened for reading only. For now,
 * we hackishly just assume that this is what _K_FILE_MODE_OPEN_OR_FAIL is for.
 *
 * Secondly, at least in theory, a file could be opened for both reading and
 * writing. We currently do not support this. If it turns out that we *have*
 * to support it, we could do it as follows: Initially open the file for
 * reading. If a write is attempted, store the file offset, close the file,
 * if necessary create a mirror clone (i.e., clone it into a suitably named
 * savefile), then open the file (resp. its clone for writing) and seek to the
 * correct position. If later a read is attempted, we again close and re-open.
 *
 * However, before putting any effort into implementing such an error-prone
 * scheme, we are well advised to first determine whether any game needs this
 * at all, and for what. Based on that, we can maybe come up with a better waybill
 * to provide this functionality.
 */
 
 

FileHandle::FileHandle() : _in(0), _out(0) {
}

FileHandle::~FileHandle() {
	close();
}

void FileHandle::close() {
	delete _in;
	delete _out;
	_in = 0;
	_out = 0;
	_name.clear();
}

bool FileHandle::isOpen() const {
	return _in || _out;
}



static int _savegame_indices_nr = -1; // means 'uninitialized'

struct SavegameDesc {
	int id;
	int date;
	int time;
};

static SavegameDesc _savegame_indices[MAX_SAVEGAME_NR];


enum {
	_K_FILE_MODE_OPEN_OR_CREATE = 0,
	_K_FILE_MODE_OPEN_OR_FAIL = 1,
	_K_FILE_MODE_CREATE = 2
};



void file_open(EngineState *s, const char *filename, int mode) {
	const Common::String wrappedName = ((Sci::SciEngine*)g_engine)->wrapFilename(filename);
	Common::SeekableReadStream *inFile = 0;
	Common::WriteStream *outFile = 0;
	Common::SaveFileManager *saveFileMan = g_engine->getSaveFileManager();

	if (mode == _K_FILE_MODE_OPEN_OR_FAIL) {
		// Try to open file, abort if not possible
		inFile = saveFileMan->openForLoading(wrappedName.c_str());
		// If no matching savestate exists: fall back to reading from a regular file
		if (!inFile)
			inFile = SearchMan.createReadStreamForMember(filename);
		if (!inFile)
			warning("file_open(_K_FILE_MODE_OPEN_OR_FAIL) failed to open file '%s'", filename);
	} else if (mode == _K_FILE_MODE_CREATE) {
		// Create the file, destroying any content it might have had
		outFile = saveFileMan->openForSaving(wrappedName.c_str());
		if (!outFile)
			warning("file_open(_K_FILE_MODE_CREATE) failed to create file '%s'", filename);
	} else if (mode == _K_FILE_MODE_OPEN_OR_CREATE) {
		// Try to open file, create it if it doesn't exist

		// FIXME: I am disabling this for now, as it's not quite clear what
		// should happen if the given file already exists... open it for appending?
		// Or (more likely), open it for reading *and* writing? We may have to
		// clone the file for that, etc., see also the long comment at the start
		// of this file.
		// We really need some examples on how this is used.
		error("file_open(_K_FILE_MODE_OPEN_OR_CREATE) File creation currently not supported");
	} else {
		error("file_open: unsupported mode %d", mode);
	}

	if (!inFile && !outFile) { // Failed
		debug(3, "file_open() failed");
		s->r_acc = make_reg(0, 0xffff);
		return;
	}


#if 0
	// FIXME: The old FreeSCI code for opening a file. Left as a reference, as apparently
	// the implementation below used to work well enough.

	SCIkdebug(SCIkFILE, "Opening file %s with mode %d\n", filename, mode);
	if ((mode == _K_FILE_MODE_OPEN_OR_FAIL) || (mode == _K_FILE_MODE_OPEN_OR_CREATE)) {
		file = sci_fopen(filename, "r" FO_BINARY "+"); // Attempt to open existing file
		SCIkdebug(SCIkFILE, "Opening file %s with mode %d\n", filename, mode);
		if (!file) {
			SCIkdebug(SCIkFILE, "Failed. Attempting to copy from resource dir...\n");
			file = f_open_mirrored(s, filename);
			if (file)
				SCIkdebug(SCIkFILE, "Success!\n");
			else
				SCIkdebug(SCIkFILE, "Not found.\n");
		}
	}

	if ((!file) && ((mode == _K_FILE_MODE_OPEN_OR_CREATE) || (mode == _K_FILE_MODE_CREATE))) {
		file = sci_fopen(filename, "w" FO_BINARY "+"); /* Attempt to create file */
		SCIkdebug(SCIkFILE, "Creating file %s with mode %d\n", filename, mode);
	}
	if (!file) { // Failed
		SCIkdebug(SCIkFILE, "file_open() failed\n");
		s->r_acc = make_reg(0, 0xffff);
		return;
	}
#endif

	// Find a free file handle
	uint handle = 1; // Ignore _fileHandles[0]
	while ((handle < s->_fileHandles.size()) && s->_fileHandles[handle].isOpen())
		handle++;

	if (handle == s->_fileHandles.size()) { // Hit size limit => Allocate more space
		s->_fileHandles.resize(s->_fileHandles.size() + 1);
	}

	s->_fileHandles[handle]._in = inFile;
	s->_fileHandles[handle]._out = outFile;
	s->_fileHandles[handle]._name = filename;

	s->r_acc = make_reg(0, handle);
	
	debug(3, " -> opened file '%s' with handle %d", filename, handle);
}

reg_t kFOpen(EngineState *s, int funct_nr, int argc, reg_t *argv) {
	char *name = kernel_dereference_char_pointer(s, argv[0], 0);
	int mode = UKPV(1);

	debug(3, "kFOpen(%s,0x%x)", name, mode);
	file_open(s, name, mode);
	return s->r_acc;
}

static FileHandle *getFileFromHandle(EngineState *s, uint handle) {
	if (handle == 0) {
		error("Attempt to use file handle 0");
		return 0;
	}

	if ((handle >= s->_fileHandles.size()) || !s->_fileHandles[handle].isOpen()) {
		error("Attempt to use invalid/unused file handle %d", handle);
		return 0;
	}

	return &s->_fileHandles[handle];
}

void file_close(EngineState *s, int handle) {
	SCIkdebug(SCIkFILE, "Closing file %d\n", handle);

	FileHandle *f = getFileFromHandle(s, handle);
	if (f)
		f->close();
}

reg_t kFClose(EngineState *s, int funct_nr, int argc, reg_t *argv) {
	debug(3, "kFClose(%d)", UKPV(0));
	file_close(s, UKPV(0));
	return s->r_acc;
}

void fwrite_wrapper(EngineState *s, int handle, char *data, int length) {
	SCIkdebug(SCIkFILE, "fwrite()'ing \"%s\" to handle %d\n", data, handle);

	FileHandle *f = getFileFromHandle(s, handle);
	if (!f)
		return;

	if (!f->_out) {
		error("fgets_wrapper: Trying to write to file '%s' opened for reading", f->_name.c_str());
		return;
	}

	f->_out->write(data, length);
}

reg_t kFPuts(EngineState *s, int funct_nr, int argc, reg_t *argv) {
	int handle = UKPV(0);
	char *data = kernel_dereference_char_pointer(s, argv[1], 0);

	fwrite_wrapper(s, handle, data, strlen(data));
	return s->r_acc;
}

static void fgets_wrapper(EngineState *s, char *dest, int maxsize, int handle) {
	SCIkdebug(SCIkFILE, "FGets'ing %d bytes from handle %d\n", maxsize, handle);

	FileHandle *f = getFileFromHandle(s, handle);
	if (!f)
		return;

	if (!f->_in) {
		error("fgets_wrapper: Trying to read from file '%s' opened for writing", f->_name.c_str());
		return;
	}
	f->_in->readLine_NEW(dest, maxsize);

	SCIkdebug(SCIkFILE, "FGets'ed \"%s\"\n", dest);
}

static void fread_wrapper(EngineState *s, char *dest, int bytes, int handle) {
	SCIkdebug(SCIkFILE, "fread()'ing %d bytes from handle %d\n", bytes, handle);

	FileHandle *f = getFileFromHandle(s, handle);
	if (!f)
		return;

	if (!f->_in) {
		error("fread_wrapper: Trying to read from file '%s' opened for writing", f->_name.c_str());
		return;
	}

	s->r_acc = make_reg(0, f->_in->read(dest, bytes));
}

static void fseek_wrapper(EngineState *s, int handle, int offset, int whence) {
	FileHandle *f = getFileFromHandle(s, handle);
	if (!f)
		return;

	if (!f->_in) {
		error("fseek_wrapper: Trying to seek in file '%s' opened for writing", f->_name.c_str());
		return;
	}

	s->r_acc = make_reg(0, f->_in->seek(offset, whence));
}

reg_t kFGets(EngineState *s, int funct_nr, int argc, reg_t *argv) {
	char *dest = kernel_dereference_char_pointer(s, argv[0], 0);
	int maxsize = UKPV(1);
	int handle = UKPV(2);

	debug(3, "kFGets(%d,%d)", handle, maxsize);
	fgets_wrapper(s, dest, maxsize, handle);
	return argv[0];
}

/**
 * Writes the cwd to the supplied address and returns the address in acc.
 */
reg_t kGetCWD(EngineState *s, int funct_nr, int argc, reg_t *argv) {
	char *targetaddr = kernel_dereference_char_pointer(s, argv[0], 0);

	// We do not let the scripts see the file system, instead pretending
	// we are always in the same directory.
	// TODO/FIXME: Is "/" a good value? Maybe "" or "." or "C:\" are better?
	strcpy(targetaddr, "/");

	debug(3, "kGetCWD() -> %s", targetaddr);

	return argv[0];
}

void delete_savegame(EngineState *s, int savedir_nr) {
	Common::String filename = ((Sci::SciEngine*)g_engine)->getSavegameName(savedir_nr);

	sciprintf("Deleting savegame '%s'\n", filename.c_str());

	Common::SaveFileManager *saveFileMan = g_engine->getSaveFileManager();
	saveFileMan->removeSavefile(filename.c_str());
}

enum {
	K_DEVICE_INFO_GET_DEVICE = 0,
	K_DEVICE_INFO_GET_CURRENT_DEVICE = 1,
	K_DEVICE_INFO_PATHS_EQUAL = 2,
	K_DEVICE_INFO_IS_FLOPPY = 3,
	K_DEVICE_INFO_GET_SAVECAT_NAME = 7,
	K_DEVICE_INFO_GET_SAVEFILE_NAME = 8
};

reg_t kDeviceInfo(EngineState *s, int funct_nr, int argc, reg_t *argv) {
	int mode = UKPV(0);
	char *game_prefix, *input_s, *output_s;

	switch (mode) {
	case K_DEVICE_INFO_GET_DEVICE:
		input_s = kernel_dereference_char_pointer(s, argv[1], 0);
		output_s = kernel_dereference_char_pointer(s, argv[2], 0);
		assert(input_s != output_s);

		strcpy(output_s, "/");
		debug(3, "K_DEVICE_INFO_GET_DEVICE(%s) -> %s", input_s, output_s);
		break;

	case K_DEVICE_INFO_GET_CURRENT_DEVICE:
		output_s = kernel_dereference_char_pointer(s, argv[1], 0);

		strcpy(output_s, "/");
		debug(3, "K_DEVICE_INFO_GET_CURRENT_DEVICE() -> %s", output_s);
		break;

	case K_DEVICE_INFO_PATHS_EQUAL: {
		char *path1_s = kernel_dereference_char_pointer(s, argv[1], 0);
		char *path2_s = kernel_dereference_char_pointer(s, argv[2], 0);
		debug(3, "K_DEVICE_INFO_PATHS_EQUAL(%s,%s)", path1_s, path2_s);

		return make_reg(0, Common::matchString(path2_s, path1_s, true));
		}
		break;

	case K_DEVICE_INFO_IS_FLOPPY:
		input_s = kernel_dereference_char_pointer(s, argv[1], 0);
		debug(3, "K_DEVICE_INFO_IS_FLOPPY(%s)\n", input_s);
		return NULL_REG; /* Never */

	/* SCI uses these in a less-than-portable way to delete savegames.
	** Read http://www-plan.cs.colorado.edu/creichen/freesci-logs/2005.10/log20051019.html
	** for more information on our workaround for this.
	*/
	case K_DEVICE_INFO_GET_SAVECAT_NAME: {
		output_s = kernel_dereference_char_pointer(s, argv[1], 0);
		game_prefix = kernel_dereference_char_pointer(s, argv[2], 0);

		sprintf(output_s, "__throwaway");
		debug(3, "K_DEVICE_INFO_GET_SAVECAT_NAME(%s) -> %s", game_prefix, output_s);
		}

	break;
	case K_DEVICE_INFO_GET_SAVEFILE_NAME: {
		output_s = kernel_dereference_char_pointer(s, argv[1], 0);
		game_prefix = kernel_dereference_char_pointer(s, argv[2], 0);
		int savegame_id = UKPV(3);
		sprintf(output_s, "__throwaway");
		debug(3, "K_DEVICE_INFO_GET_SAVEFILE_NAME(%s,%d) -> %s", game_prefix, savegame_id, output_s);
		delete_savegame(s, savegame_id);
		}
		break;

	default:
		SCIkwarn(SCIkERROR, "Unknown DeviceInfo() sub-command: %d\n", mode);
		break;
	}

	return s->r_acc;
}

reg_t kGetSaveDir(EngineState *s, int funct_nr, int argc, reg_t *argv) {
	return make_reg(s->sys_strings_segment, SYS_STRING_SAVEDIR);
}

reg_t kCheckFreeSpace(EngineState *s, int funct_nr, int argc, reg_t *argv) {
	char *path = kernel_dereference_char_pointer(s, argv[0], 0);

	debug(3, "kCheckFreeSpace(%s)", path);
	// We simply always pretend that there is enough space.
	// The alternative would be to write a big test file, which is not nice
	// on systems where doing so is very slow.
	return make_reg(0, 1);
}

static int _savegame_index_struct_compare(const void *a, const void *b) {
	SavegameDesc *A = (SavegameDesc *)a;
	SavegameDesc *B = (SavegameDesc *)b;

	if (B->date != A->date)
		return B->date - A->date;
	return B->time - A->time;
}

static void update_savegame_indices() {
	int i;

	_savegame_indices_nr = 0;

	Common::SaveFileManager *saveFileMan = g_engine->getSaveFileManager();

	for (i = 0; i < MAX_SAVEGAME_NR; i++) {
		Common::String filename = ((Sci::SciEngine*)g_engine)->getSavegameName(i);
		Common::SeekableReadStream *in;
		if ((in = saveFileMan->openForLoading(filename.c_str()))) {
			SavegameMetadata meta;
			if (!get_savegame_metadata(in, &meta)) {
				// invalid
				delete in;
				continue;
			}
			delete in;

			fprintf(stderr, "Savegame in %s file ok\n", filename.c_str());
			_savegame_indices[_savegame_indices_nr].id = i;
			_savegame_indices[_savegame_indices_nr].date = meta.savegame_date;
			_savegame_indices[_savegame_indices_nr].time = meta.savegame_time;
			_savegame_indices_nr++;
		}
	}

	qsort(_savegame_indices, _savegame_indices_nr, sizeof(SavegameDesc), _savegame_index_struct_compare);
}

reg_t kCheckSaveGame(EngineState *s, int funct_nr, int argc, reg_t *argv) {
	char *game_id = kernel_dereference_char_pointer(s, argv[0], 0);
	int savedir_nr = UKPV(1);

	debug(3, "kCheckSaveGame(%s, %d)", game_id, savedir_nr);
	if (_savegame_indices_nr < 0) {
		warning("Savegame index list not initialized");
		update_savegame_indices();
	}

	savedir_nr = _savegame_indices[savedir_nr].id;

	if (savedir_nr > MAX_SAVEGAME_NR - 1) {
		return NULL_REG;
	}

	Common::SaveFileManager *saveFileMan = g_engine->getSaveFileManager();
	Common::String filename = ((Sci::SciEngine*)g_engine)->getSavegameName(savedir_nr);
	Common::SeekableReadStream *in;
	if ((in = saveFileMan->openForLoading(filename.c_str()))) {
		// found a savegame file

		SavegameMetadata meta;
		if (!get_savegame_metadata(in, &meta)) {
			// invalid
			s->r_acc = make_reg(0, 0);
		} else {
			s->r_acc = make_reg(0, 1);
		}
		delete in;
	} else {
		s->r_acc = make_reg(0, 1);
	}

	return s->r_acc;
}

reg_t kGetSaveFiles(EngineState *s, int funct_nr, int argc, reg_t *argv) {
	char *game_id = kernel_dereference_char_pointer(s, argv[0], 0);
	char *nametarget = kernel_dereference_char_pointer(s, argv[1], 0);
	reg_t nametarget_base = argv[1];
	reg_t *nameoffsets = kernel_dereference_reg_pointer(s, argv[2], 0);
	int i;

	debug(3, "kGetSaveFiles(%s,%s)", game_id, nametarget);
	update_savegame_indices();

	s->r_acc = NULL_REG;
	Common::SaveFileManager *saveFileMan = g_engine->getSaveFileManager();

	for (i = 0; i < _savegame_indices_nr; i++) {
		Common::String filename = ((Sci::SciEngine*)g_engine)->getSavegameName(_savegame_indices[i].id);
		Common::SeekableReadStream *in;
		if ((in = saveFileMan->openForLoading(filename.c_str()))) {
			// found a savegame file

			SavegameMetadata meta;
			if (!get_savegame_metadata(in, &meta)) {
				// invalid
				delete in;
				continue;
			}

			if (!meta.savegame_name.empty()) {
				if (meta.savegame_name.lastChar() == '\n')
					meta.savegame_name.deleteLastChar();

				*nameoffsets = s->r_acc; // Store savegame ID
				++s->r_acc.offset; // Increase number of files found

				nameoffsets++; // Make sure the next ID string address is written to the next pointer
				strncpy(nametarget, meta.savegame_name.c_str(), SCI_MAX_SAVENAME_LENGTH); // Copy identifier string
				*(nametarget + SCI_MAX_SAVENAME_LENGTH - 1) = 0; // Make sure it's terminated
				nametarget += SCI_MAX_SAVENAME_LENGTH; // Increase name offset pointer accordingly
				nametarget_base.offset += SCI_MAX_SAVENAME_LENGTH;
			}
			delete in;
		}
	}

	//free(gfname);
	*nametarget = 0; // Terminate list

	return s->r_acc;
}

reg_t kSaveGame(EngineState *s, int funct_nr, int argc, reg_t *argv) {
	char *game_id = kernel_dereference_char_pointer(s, argv[0], 0);
	int savedir_nr = UKPV(1);
	int savedir_id; // Savegame ID, derived from savedir_nr and the savegame ID list
	char *game_description = kernel_dereference_char_pointer(s, argv[2], 0);
	char *version = argc > 3 ? strdup(kernel_dereference_char_pointer(s, argv[3], 0)) : NULL;

	debug(3, "kSaveGame(%s,%d,%s,%s)", game_id, savedir_nr, game_description, version);
	s->game_version = version;

	update_savegame_indices();

	fprintf(stderr, "savedir_nr = %d\n", savedir_nr);

	if (savedir_nr >= 0 && savedir_nr < _savegame_indices_nr)
		// Overwrite
		savedir_id = _savegame_indices[savedir_nr].id;
	else if (savedir_nr >= 0 && savedir_nr < MAX_SAVEGAME_NR) {
		int i = 0;

		fprintf(stderr, "searching for hole\n");

		savedir_id = 0;

		// First, look for holes
		while (i < _savegame_indices_nr) {
			if (_savegame_indices[i].id == savedir_id) {
				++savedir_id;
				i = 0;
			} else ++i;
		}
		if (savedir_id >= MAX_SAVEGAME_NR) {
			sciprintf("Internal error: Free savegame ID is %d, shouldn't happen!\n", savedir_id);
			return NULL_REG;
		}

		// This loop terminates when savedir_id is not in [x | ex. n. _savegame_indices[n].id = x]
	} else {
		sciprintf("Savegame ID %d is not allowed!\n", savedir_nr);
		return NULL_REG;
	}

	Common::String filename = ((Sci::SciEngine*)g_engine)->getSavegameName(savedir_id);
	Common::SaveFileManager *saveFileMan = g_engine->getSaveFileManager();
	Common::OutSaveFile *out;
	if (!(out = saveFileMan->openForSaving(filename.c_str()))) {
		sciprintf("Error opening savegame \"%s\" for writing\n", filename.c_str());
		s->r_acc = NULL_REG;
		return NULL_REG;
	}

	if (gamestate_save(s, out, game_description)) {
		sciprintf("Saving the game failed.\n");
		s->r_acc = NULL_REG;
	} else {
		out->finalize();
		if (out->err()) {
			delete out;
			sciprintf("Writing the savegame failed.\n");
			s->r_acc = NULL_REG;
		} else {
			delete out;
			s->r_acc = make_reg(0, 1);
		}
	}
	free(s->game_version);
	s->game_version = NULL;

	return s->r_acc;
}

reg_t kRestoreGame(EngineState *s, int funct_nr, int argc, reg_t *argv) {
	char *game_id = kernel_dereference_char_pointer(s, argv[0], 0);
	int savedir_nr = UKPV(1);

	debug(3, "kRestoreGame(%s,%d)", game_id, savedir_nr);

	if (_savegame_indices_nr < 0) {
		warning("Savegame index list not initialized");
		update_savegame_indices();
	}

	savedir_nr = _savegame_indices[savedir_nr].id;

	if (savedir_nr > -1) {
		Common::SaveFileManager *saveFileMan = g_engine->getSaveFileManager();
		Common::String filename = ((Sci::SciEngine*)g_engine)->getSavegameName(savedir_nr);
		Common::SeekableReadStream *in;
		if ((in = saveFileMan->openForLoading(filename.c_str()))) {
			// found a savegame file

			EngineState *newstate = gamestate_restore(s, in);
			delete in;

			if (newstate) {
				s->successor = newstate;
				script_abort_flag = SCRIPT_ABORT_WITH_REPLAY; // Abort current game
				s->execution_stack_pos = s->execution_stack_base;
			} else {
				s->r_acc = make_reg(0, 1);
				sciprintf("Restoring failed (game_id = '%s').\n", game_id);
			}
			return s->r_acc;
		}
	}

	s->r_acc = make_reg(0, 1);
	sciprintf("Savegame #%d not found!\n", savedir_nr);

	return s->r_acc;
}

reg_t kValidPath(EngineState *s, int funct_nr, int argc, reg_t *argv) {
	const char *path = kernel_dereference_char_pointer(s, argv[0], 0);

	// FIXME: For now, we only accept the (fake) root dir "/" as a valid path.
	s->r_acc = make_reg(0, 0 == strcmp(path, "/"));

	debug(3, "kValidPath(%s) -> %d", path, s->r_acc.offset);

	return s->r_acc;
}

enum {
	K_FILEIO_OPEN			= 0,
	K_FILEIO_CLOSE			= 1,
	K_FILEIO_READ_RAW		= 2,
	K_FILEIO_WRITE_RAW		= 3,
	K_FILEIO_UNLINK			= 4,
	K_FILEIO_READ_STRING	= 5,
	K_FILEIO_WRITE_STRING	= 6,
	K_FILEIO_SEEK			= 7,
	K_FILEIO_FIND_FIRST		= 8,
	K_FILEIO_FIND_NEXT		= 9,
	K_FILEIO_FILE_EXISTS	= 10
};


void DirSeeker::firstFile(const char *mask, reg_t buffer) {
	
	// Verify that we are given a valid buffer
	if (!buffer.segment) {
		error("DirSeeker::firstFile('%s') invoked with invalid buffer", mask);
		_vm->r_acc = NULL_REG;
		return;
	}
	_outbuffer = buffer;

	// Obtain a list of all savefiles matching the given mask
	// TODO: Modify the mask, e.g. by prefixing "TARGET-".
	Common::SaveFileManager *saveFileMan = g_engine->getSaveFileManager();
	_savefiles = saveFileMan->listSavefiles(mask);

	// Reset the list iterator and write the first match to the output buffer, if any.
	_iter = _savefiles.begin();
	nextFile();
}

void DirSeeker::nextFile() {
	if (_iter == _savefiles.end()) {
		_vm->r_acc = NULL_REG;
		return;
	}

	char *mem = kernel_dereference_char_pointer(_vm, _outbuffer, 0);
	memset(mem, 0, 13);

	// TODO: Transform the string back into a format usable by the SCI scripts. 
	// I.e., strip any TARGET- prefix.
	const char *string = _iter->c_str();
	assert(string);
	strncpy(mem, string, 12);

	// Return the result and advance the list iterator :)
	_vm->r_acc = _outbuffer;
	++_iter;
}



reg_t kFileIO(EngineState *s, int funct_nr, int argc, reg_t *argv) {
	int func_nr = UKPV(0);

	switch (func_nr) {
	case K_FILEIO_OPEN : {
		char *name = kernel_dereference_char_pointer(s, argv[1], 0);
		int mode = UKPV(2);

		file_open(s, name, mode);
		debug(3, "K_FILEIO_OPEN(%s,0x%x)", name, mode);
		break;
	}
	case K_FILEIO_CLOSE : {
		int handle = UKPV(1);
		debug(3, "K_FILEIO_CLOSE(%d)", handle);

		file_close(s, handle);
		break;
	}
	case K_FILEIO_READ_RAW : {
		int handle = UKPV(1);
		char *dest = kernel_dereference_char_pointer(s, argv[2], 0);
		int size = UKPV(3);
		debug(3, "K_FILEIO_READ_RAW(%d,%d)", handle, size);

		fread_wrapper(s, dest, size, handle);
		break;
	}
	case K_FILEIO_WRITE_RAW : {
		int handle = UKPV(1);
		char *buf = kernel_dereference_char_pointer(s, argv[2], 0);
		int size = UKPV(3);
		debug(3, "K_FILEIO_WRITE_RAW(%d,%d)", handle, size);

		fwrite_wrapper(s, handle, buf, size);
		break;
	}
	case K_FILEIO_UNLINK : {
		char *name = kernel_dereference_char_pointer(s, argv[1], 0);
		debug(3, "K_FILEIO_UNLINK(%s)", name);

		Common::SaveFileManager *saveFileMan = g_engine->getSaveFileManager();
		const Common::String wrappedName = ((Sci::SciEngine*)g_engine)->wrapFilename(name);
		saveFileMan->removeSavefile(wrappedName.c_str());
		// TODO/FIXME: Should we return something (like, a bool indicating
		// whether deleting the save succeeded or failed)?
		break;
	}
	case K_FILEIO_READ_STRING : {
		char *dest = kernel_dereference_char_pointer(s, argv[1], 0);
		int size = UKPV(2);
		int handle = UKPV(3);
		debug(3, "K_FILEIO_READ_STRING(%d,%d)", handle, size);

		fgets_wrapper(s, dest, size, handle);
		return argv[1];
	}
	case K_FILEIO_WRITE_STRING : {
		int handle = UKPV(1);
		int size = UKPV(3);
		char *buf = kernel_dereference_char_pointer(s, argv[2], size);
		debug(3, "K_FILEIO_WRITE_STRING(%d,%d)", handle, size);

		// FIXME: What is the difference between K_FILEIO_WRITE_STRING and
		// K_FILEIO_WRITE_RAW? Normally, I would expect the difference to
		// be that the former doesn't receive a 'size' parameter. But here
		// it does. Are we missing something?
		if (buf)
			fwrite_wrapper(s, handle, buf, size);
		break;
	}
	case K_FILEIO_SEEK : {
		int handle = UKPV(1);
		int offset = UKPV(2);
		int whence = UKPV(3);
		debug(3, "K_FILEIO_SEEK(%d,%d,%d)", handle, offset, whence);

		fseek_wrapper(s, handle, offset, whence);
		break;
	}
	case K_FILEIO_FIND_FIRST : {
		char *mask = kernel_dereference_char_pointer(s, argv[1], 0);
		reg_t buf = argv[2];
		int attr = UKPV(3); // We won't use this, Win32 might, though...
		debug(3, "K_FILEIO_FIND_FIRST(%s,0x%x)", mask, attr);

#ifndef WIN32
		if (strcmp(mask, "*.*") == 0)
			strcpy(mask, "*"); // For UNIX
#endif
		s->_dirseeker.firstFile(mask, buf);

		break;
	}
	case K_FILEIO_FIND_NEXT : {
		debug(3, "K_FILEIO_FIND_NEXT()");
		s->_dirseeker.nextFile();
		break;
	}
	case K_FILEIO_FILE_EXISTS : {
		char *name = kernel_dereference_char_pointer(s, argv[1], 0);
		// TODO: Transform the name given by the scripts to us, e.g. by
		// prepending TARGET-
		// TODO: We may have to also check for a regular file with the
		// given name, using File::exists(). Really depends on *how*
		// scripts use this opcode. Need more test data...
		Common::SaveFileManager *saveFileMan = g_engine->getSaveFileManager();
		bool exists = !saveFileMan->listSavefiles(name).empty();

		s->r_acc = make_reg(0, exists);
		debug(3, "K_FILEIO_FILE_EXISTS(%s) -> %d", name, s->r_acc.offset);
		break;
	}
	default :
		SCIkwarn(SCIkERROR, "Unknown FileIO() sub-command: %d\n", func_nr);
	}

	return s->r_acc;
}

} // End of namespace Sci