summaryrefslogtreecommitdiff
path: root/src/saveload/saveload.h
blob: b6e843c9918186ecdf0ebc994f1b5bf8489af865 (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
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
/*
 * This file is part of OpenTTD.
 * OpenTTD 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, version 2.
 * OpenTTD 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 OpenTTD. If not, see <http://www.gnu.org/licenses/>.
 */

/** @file saveload.h Functions/types related to saving and loading games. */

#ifndef SAVELOAD_H
#define SAVELOAD_H

#include "../fileio_type.h"
#include "../strings_type.h"
#include "../core/span_type.hpp"
#include <optional>
#include <string>
#include <vector>

/** SaveLoad versions
 * Previous savegame versions, the trunk revision where they were
 * introduced and the released version that had that particular
 * savegame version.
 * Up to savegame version 18 there is a minor version as well.
 *
 * Older entries keep their original numbering.
 *
 * Newer entries should use a descriptive labels, numeric version
 * and PR can be added to comment.
 *
 * Note that this list must not be reordered.
 */
enum SaveLoadVersion : uint16 {
	SL_MIN_VERSION,                         ///< First savegame version

	SLV_1,                                  ///<   1.0         0.1.x, 0.2.x
	SLV_2,                                  /**<   2.0         0.3.0
	                                         *     2.1         0.3.1, 0.3.2 */
	SLV_3,                                  ///<   3.x         lost
	SLV_4,                                  /**<   4.0     1
	                                         *     4.1   122   0.3.3, 0.3.4
	                                         *     4.2  1222   0.3.5
	                                         *     4.3  1417
	                                         *     4.4  1426 */

	SLV_5,                                  /**<   5.0  1429
	                                         *     5.1  1440
	                                         *     5.2  1525   0.3.6 */
	SLV_6,                                  /**<   6.0  1721
	                                         *     6.1  1768 */
	SLV_7,                                  ///<   7.0  1770
	SLV_8,                                  ///<   8.0  1786
	SLV_9,                                  ///<   9.0  1909

	SLV_10,                                 ///<  10.0  2030
	SLV_11,                                 /**<  11.0  2033
	                                         *    11.1  2041 */
	SLV_12,                                 ///<  12.1  2046
	SLV_13,                                 ///<  13.1  2080   0.4.0, 0.4.0.1
	SLV_14,                                 ///<  14.0  2441

	SLV_15,                                 ///<  15.0  2499
	SLV_16,                                 /**<  16.0  2817
	                                         *    16.1  3155 */
	SLV_17,                                 /**<  17.0  3212
	                                         *    17.1  3218 */
	SLV_18,                                 ///<  18    3227
	SLV_19,                                 ///<  19    3396

	SLV_20,                                 ///<  20    3403
	SLV_21,                                 ///<  21    3472   0.4.x
	SLV_22,                                 ///<  22    3726
	SLV_23,                                 ///<  23    3915
	SLV_24,                                 ///<  24    4150

	SLV_25,                                 ///<  25    4259
	SLV_26,                                 ///<  26    4466
	SLV_27,                                 ///<  27    4757
	SLV_28,                                 ///<  28    4987
	SLV_29,                                 ///<  29    5070

	SLV_30,                                 ///<  30    5946
	SLV_31,                                 ///<  31    5999
	SLV_32,                                 ///<  32    6001
	SLV_33,                                 ///<  33    6440
	SLV_34,                                 ///<  34    6455

	SLV_35,                                 ///<  35    6602
	SLV_36,                                 ///<  36    6624
	SLV_37,                                 ///<  37    7182
	SLV_38,                                 ///<  38    7195
	SLV_39,                                 ///<  39    7269

	SLV_40,                                 ///<  40    7326
	SLV_41,                                 ///<  41    7348   0.5.x
	SLV_42,                                 ///<  42    7573
	SLV_43,                                 ///<  43    7642
	SLV_44,                                 ///<  44    8144

	SLV_45,                                 ///<  45    8501
	SLV_46,                                 ///<  46    8705
	SLV_47,                                 ///<  47    8735
	SLV_48,                                 ///<  48    8935
	SLV_49,                                 ///<  49    8969

	SLV_50,                                 ///<  50    8973
	SLV_51,                                 ///<  51    8978
	SLV_52,                                 ///<  52    9066
	SLV_53,                                 ///<  53    9316
	SLV_54,                                 ///<  54    9613

	SLV_55,                                 ///<  55    9638
	SLV_56,                                 ///<  56    9667
	SLV_57,                                 ///<  57    9691
	SLV_58,                                 ///<  58    9762
	SLV_59,                                 ///<  59    9779

	SLV_60,                                 ///<  60    9874
	SLV_61,                                 ///<  61    9892
	SLV_62,                                 ///<  62    9905
	SLV_63,                                 ///<  63    9956
	SLV_64,                                 ///<  64   10006

	SLV_65,                                 ///<  65   10210
	SLV_66,                                 ///<  66   10211
	SLV_67,                                 ///<  67   10236
	SLV_68,                                 ///<  68   10266
	SLV_69,                                 ///<  69   10319

	SLV_70,                                 ///<  70   10541
	SLV_71,                                 ///<  71   10567
	SLV_72,                                 ///<  72   10601
	SLV_73,                                 ///<  73   10903
	SLV_74,                                 ///<  74   11030

	SLV_75,                                 ///<  75   11107
	SLV_76,                                 ///<  76   11139
	SLV_77,                                 ///<  77   11172
	SLV_78,                                 ///<  78   11176
	SLV_79,                                 ///<  79   11188

	SLV_80,                                 ///<  80   11228
	SLV_81,                                 ///<  81   11244
	SLV_82,                                 ///<  82   11410
	SLV_83,                                 ///<  83   11589
	SLV_84,                                 ///<  84   11822

	SLV_85,                                 ///<  85   11874
	SLV_86,                                 ///<  86   12042
	SLV_87,                                 ///<  87   12129
	SLV_88,                                 ///<  88   12134
	SLV_89,                                 ///<  89   12160

	SLV_90,                                 ///<  90   12293
	SLV_91,                                 ///<  91   12347
	SLV_92,                                 ///<  92   12381   0.6.x
	SLV_93,                                 ///<  93   12648
	SLV_94,                                 ///<  94   12816

	SLV_95,                                 ///<  95   12924
	SLV_96,                                 ///<  96   13226
	SLV_97,                                 ///<  97   13256
	SLV_98,                                 ///<  98   13375
	SLV_99,                                 ///<  99   13838

	SLV_100,                                ///< 100   13952
	SLV_101,                                ///< 101   14233
	SLV_102,                                ///< 102   14332
	SLV_103,                                ///< 103   14598
	SLV_104,                                ///< 104   14735

	SLV_105,                                ///< 105   14803
	SLV_106,                                ///< 106   14919
	SLV_107,                                ///< 107   15027
	SLV_108,                                ///< 108   15045
	SLV_109,                                ///< 109   15075

	SLV_110,                                ///< 110   15148
	SLV_111,                                ///< 111   15190
	SLV_112,                                ///< 112   15290
	SLV_113,                                ///< 113   15340
	SLV_114,                                ///< 114   15601

	SLV_115,                                ///< 115   15695
	SLV_116,                                ///< 116   15893   0.7.x
	SLV_117,                                ///< 117   16037
	SLV_118,                                ///< 118   16129
	SLV_119,                                ///< 119   16242

	SLV_120,                                ///< 120   16439
	SLV_121,                                ///< 121   16694
	SLV_122,                                ///< 122   16855
	SLV_123,                                ///< 123   16909
	SLV_124,                                ///< 124   16993

	SLV_125,                                ///< 125   17113
	SLV_126,                                ///< 126   17433
	SLV_127,                                ///< 127   17439
	SLV_128,                                ///< 128   18281
	SLV_129,                                ///< 129   18292

	SLV_130,                                ///< 130   18404
	SLV_131,                                ///< 131   18481
	SLV_132,                                ///< 132   18522
	SLV_133,                                ///< 133   18674
	SLV_134,                                ///< 134   18703

	SLV_135,                                ///< 135   18719
	SLV_136,                                ///< 136   18764
	SLV_137,                                ///< 137   18912
	SLV_138,                                ///< 138   18942   1.0.x
	SLV_139,                                ///< 139   19346

	SLV_140,                                ///< 140   19382
	SLV_141,                                ///< 141   19799
	SLV_142,                                ///< 142   20003
	SLV_143,                                ///< 143   20048
	SLV_144,                                ///< 144   20334

	SLV_145,                                ///< 145   20376
	SLV_146,                                ///< 146   20446
	SLV_147,                                ///< 147   20621
	SLV_148,                                ///< 148   20659
	SLV_149,                                ///< 149   20832

	SLV_150,                                ///< 150   20857
	SLV_151,                                ///< 151   20918
	SLV_152,                                ///< 152   21171
	SLV_153,                                ///< 153   21263
	SLV_154,                                ///< 154   21426

	SLV_155,                                ///< 155   21453
	SLV_156,                                ///< 156   21728
	SLV_157,                                ///< 157   21862
	SLV_158,                                ///< 158   21933
	SLV_159,                                ///< 159   21962

	SLV_160,                                ///< 160   21974   1.1.x
	SLV_161,                                ///< 161   22567
	SLV_162,                                ///< 162   22713
	SLV_163,                                ///< 163   22767
	SLV_164,                                ///< 164   23290

	SLV_165,                                ///< 165   23304
	SLV_166,                                ///< 166   23415
	SLV_167,                                ///< 167   23504
	SLV_168,                                ///< 168   23637
	SLV_169,                                ///< 169   23816

	SLV_170,                                ///< 170   23826
	SLV_171,                                ///< 171   23835
	SLV_172,                                ///< 172   23947
	SLV_173,                                ///< 173   23967   1.2.0-RC1
	SLV_174,                                ///< 174   23973   1.2.x

	SLV_175,                                ///< 175   24136
	SLV_176,                                ///< 176   24446
	SLV_177,                                ///< 177   24619
	SLV_178,                                ///< 178   24789
	SLV_179,                                ///< 179   24810

	SLV_180,                                ///< 180   24998   1.3.x
	SLV_181,                                ///< 181   25012
	SLV_182,                                ///< 182   25115 FS#5492, r25259, r25296 Goal status
	SLV_183,                                ///< 183   25363 Cargodist
	SLV_184,                                ///< 184   25508 Unit localisation split

	SLV_185,                                ///< 185   25620 Storybooks
	SLV_186,                                ///< 186   25833 Objects storage
	SLV_187,                                ///< 187   25899 Linkgraph - restricted flows
	SLV_188,                                ///< 188   26169 v1.4  FS#5831 Unify RV travel time
	SLV_189,                                ///< 189   26450 Hierarchical vehicle subgroups

	SLV_190,                                ///< 190   26547 Separate order travel and wait times
	SLV_191,                                ///< 191   26636 FS#6026 Fix disaster vehicle storage (No bump)
	                                        ///< 191   26646 FS#6041 Linkgraph - store locations
	SLV_192,                                ///< 192   26700 FS#6066 Fix saving of order backups
	SLV_193,                                ///< 193   26802
	SLV_194,                                ///< 194   26881 v1.5

	SLV_195,                                ///< 195   27572 v1.6.1
	SLV_196,                                ///< 196   27778 v1.7
	SLV_197,                                ///< 197   27978 v1.8
	SLV_198,                                ///< 198  PR#6763 Switch town growth rate and counter to actual game ticks
	SLV_EXTEND_CARGOTYPES,                  ///< 199  PR#6802 Extend cargotypes to 64

	SLV_EXTEND_RAILTYPES,                   ///< 200  PR#6805 Extend railtypes to 64, adding uint16 to map array.
	SLV_EXTEND_PERSISTENT_STORAGE,          ///< 201  PR#6885 Extend NewGRF persistent storages.
	SLV_EXTEND_INDUSTRY_CARGO_SLOTS,        ///< 202  PR#6867 Increase industry cargo slots to 16 in, 16 out
	SLV_SHIP_PATH_CACHE,                    ///< 203  PR#7072 Add path cache for ships
	SLV_SHIP_ROTATION,                      ///< 204  PR#7065 Add extra rotation stages for ships.

	SLV_GROUP_LIVERIES,                     ///< 205  PR#7108 Livery storage change and group liveries.
	SLV_SHIPS_STOP_IN_LOCKS,                ///< 206  PR#7150 Ship/lock movement changes.
	SLV_FIX_CARGO_MONITOR,                  ///< 207  PR#7175 v1.9  Cargo monitor data packing fix to support 64 cargotypes.
	SLV_TOWN_CARGOGEN,                      ///< 208  PR#6965 New algorithms for town building cargo generation.
	SLV_SHIP_CURVE_PENALTY,                 ///< 209  PR#7289 Configurable ship curve penalties.

	SLV_SERVE_NEUTRAL_INDUSTRIES,           ///< 210  PR#7234 Company stations can serve industries with attached neutral stations.
	SLV_ROADVEH_PATH_CACHE,                 ///< 211  PR#7261 Add path cache for road vehicles.
	SLV_REMOVE_OPF,                         ///< 212  PR#7245 Remove OPF.
	SLV_TREES_WATER_CLASS,                  ///< 213  PR#7405 WaterClass update for tree tiles.
	SLV_ROAD_TYPES,                         ///< 214  PR#6811 NewGRF road types.

	SLV_SCRIPT_MEMLIMIT,                    ///< 215  PR#7516 Limit on AI/GS memory consumption.
	SLV_MULTITILE_DOCKS,                    ///< 216  PR#7380 Multiple docks per station.
	SLV_TRADING_AGE,                        ///< 217  PR#7780 Configurable company trading age.
	SLV_ENDING_YEAR,                        ///< 218  PR#7747 v1.10  Configurable ending year.
	SLV_REMOVE_TOWN_CARGO_CACHE,            ///< 219  PR#8258 Remove town cargo acceptance and production caches.

	/* Patchpacks for a while considered it a good idea to jump a few versions
	 * above our version for their savegames. But as time continued, this gap
	 * has been closing, up to the point we would start to reuse versions from
	 * their patchpacks. This is not a problem from our perspective: the
	 * savegame will simply fail to load because they all contain chunks we
	 * cannot digest. But, this gives for ugly errors. As we have plenty of
	 * versions anyway, we simply skip the versions we know belong to
	 * patchpacks. This way we can present the user with a clean error
	 * indicate they are loading a savegame from a patchpack.
	 * For future patchpack creators: please follow a system like JGRPP, where
	 * the version is masked with 0x8000, and the true version is stored in
	 * its own chunk with feature toggles.
	 */
	SLV_START_PATCHPACKS,                   ///< 220  First known patchpack to use a version just above ours.
	SLV_END_PATCHPACKS = 286,               ///< 286  Last known patchpack to use a version just above ours.

	SLV_GS_INDUSTRY_CONTROL,                ///< 287  PR#7912 and PR#8115 GS industry control.
	SLV_VEH_MOTION_COUNTER,                 ///< 288  PR#8591 Desync safe motion counter
	SLV_INDUSTRY_TEXT,                      ///< 289  PR#8576 v1.11.0-RC1  Additional GS text for industries.

	SLV_MAPGEN_SETTINGS_REVAMP,             ///< 290  PR#8891 v1.11  Revamp of some mapgen settings (snow coverage, desert coverage, heightmap height, custom terrain type).
	SLV_GROUP_REPLACE_WAGON_REMOVAL,        ///< 291  PR#7441 Per-group wagon removal flag.
	SLV_CUSTOM_SUBSIDY_DURATION,            ///< 292  PR#9081 Configurable subsidy duration.
	SLV_SAVELOAD_LIST_LENGTH,               ///< 293  PR#9374 Consistency in list length with SL_STRUCT / SL_STRUCTLIST / SL_DEQUE / SL_REFLIST.
	SLV_RIFF_TO_ARRAY,                      ///< 294  PR#9375 Changed many CH_RIFF chunks to CH_ARRAY chunks.

	SLV_TABLE_CHUNKS,                       ///< 295  PR#9322 Introduction of CH_TABLE and CH_SPARSE_TABLE.

	SL_MAX_VERSION,                         ///< Highest possible saveload version
};

/** Save or load result codes. */
enum SaveOrLoadResult {
	SL_OK     = 0, ///< completed successfully
	SL_ERROR  = 1, ///< error that was caught before internal structures were modified
	SL_REINIT = 2, ///< error that was caught in the middle of updating game state, need to clear it. (can only happen during load)
};

/** Deals with the type of the savegame, independent of extension */
struct FileToSaveLoad {
	SaveLoadOperation file_op;           ///< File operation to perform.
	DetailedFileType detail_ftype;   ///< Concrete file type (PNG, BMP, old save, etc).
	AbstractFileType abstract_ftype; ///< Abstract type of file (scenario, heightmap, etc).
	std::string name;                ///< Name of the file.
	char title[255];                 ///< Internal name of the game.

	void SetMode(FiosType ft);
	void SetMode(SaveLoadOperation fop, AbstractFileType aft, DetailedFileType dft);
	void SetName(const char *name);
	void SetTitle(const char *title);
};

/** Types of save games. */
enum SavegameType {
	SGT_TTD,    ///< TTD  savegame (can be detected incorrectly)
	SGT_TTDP1,  ///< TTDP savegame ( -//- ) (data at NW border)
	SGT_TTDP2,  ///< TTDP savegame in new format (data at SE border)
	SGT_OTTD,   ///< OTTD savegame
	SGT_TTO,    ///< TTO savegame
	SGT_INVALID = 0xFF, ///< broken savegame (used internally)
};

extern FileToSaveLoad _file_to_saveload;

void GenerateDefaultSaveName(char *buf, const char *last);
void SetSaveLoadError(StringID str);
const char *GetSaveLoadErrorString();
SaveOrLoadResult SaveOrLoad(const std::string &filename, SaveLoadOperation fop, DetailedFileType dft, Subdirectory sb, bool threaded = true);
void WaitTillSaved();
void ProcessAsyncSaveFinish();
void DoExitSave();

SaveOrLoadResult SaveWithFilter(struct SaveFilter *writer, bool threaded);
SaveOrLoadResult LoadWithFilter(struct LoadFilter *reader);

typedef void ChunkSaveLoadProc();
typedef void AutolengthProc(void *arg);

/** Type of a chunk. */
enum ChunkType {
	CH_RIFF = 0,
	CH_ARRAY = 1,
	CH_SPARSE_ARRAY = 2,
	CH_TABLE = 3,
	CH_SPARSE_TABLE = 4,

	CH_TYPE_MASK = 0xf, ///< All ChunkType values have to be within this mask.
	CH_READONLY, ///< Chunk is never saved.
};

/** Handlers and description of chunk. */
struct ChunkHandler {
	uint32 id;                          ///< Unique ID (4 letters).
	ChunkSaveLoadProc *save_proc;       ///< Save procedure of the chunk.
	ChunkSaveLoadProc *load_proc;       ///< Load procedure of the chunk.
	ChunkSaveLoadProc *ptrs_proc;       ///< Manipulate pointers in the chunk.
	ChunkSaveLoadProc *load_check_proc; ///< Load procedure for game preview.
	ChunkType type;                     ///< Type of the chunk. @see ChunkType
};

/** A table of ChunkHandler entries. */
using ChunkHandlerTable = span<const ChunkHandler>;

/** A table of SaveLoad entries. */
using SaveLoadTable = span<const struct SaveLoad>;

/** A table of SaveLoadCompat entries. */
using SaveLoadCompatTable = span<const struct SaveLoadCompat>;

/** Handler for saving/loading an object to/from disk. */
class SaveLoadHandler {
public:
	std::optional<std::vector<SaveLoad>> load_description;

	virtual ~SaveLoadHandler() {}

	/**
	 * Save the object to disk.
	 * @param object The object to store.
	 */
	virtual void Save(void *object) const {}

	/**
	 * Load the object from disk.
	 * @param object The object to load.
	 */
	virtual void Load(void *object) const {}

	/**
	 * Similar to load, but used only to validate savegames.
	 * @param object The object to load.
	 */
	virtual void LoadCheck(void *object) const {}

	/**
	 * A post-load callback to fix #SL_REF integers into pointers.
	 * @param object The object to fix.
	 */
	virtual void FixPointers(void *object) const {}

	/**
	 * Get the description of the fields in the savegame.
	 */
	virtual SaveLoadTable GetDescription() const = 0;

	/**
	 * Get the pre-header description of the fields in the savegame.
	 */
	virtual SaveLoadCompatTable GetCompatDescription() const { return {}; }

	/**
	 * Get the description for how to load the chunk. Depending on the
	 * savegame version this can either use the headers in the savegame or
	 * fall back to backwards compatibility and uses hard-coded headers.
	 */
	SaveLoadTable GetLoadDescription() const;
};

/**
 * Default handler for saving/loading an object to/from disk.
 *
 * This handles a few common things for handlers, meaning the actual handler
 * needs less code.
 *
 * Usage: class SlMine : public DefaultSaveLoadHandler<SlMine, MyObject> {}
 *
 * @tparam TImpl The class initializing this template.
 * @tparam TObject The class of the object using this SaveLoadHandler.
 */
template <class TImpl, class TObject>
class DefaultSaveLoadHandler : public SaveLoadHandler {
public:
	SaveLoadTable GetDescription() const override { return static_cast<const TImpl *>(this)->description; }

	virtual void Save(TObject *object) const {}
	void Save(void *object) const override { this->Save(static_cast<TObject *>(object)); }

	virtual void Load(TObject *object) const {}
	void Load(void *object) const override { this->Load(static_cast<TObject *>(object)); }

	virtual void LoadCheck(TObject *object) const {}
	void LoadCheck(void *object) const override { this->LoadCheck(static_cast<TObject *>(object)); }

	virtual void FixPointers(TObject *object) const {}
	void FixPointers(void *object) const override { this->FixPointers(static_cast<TObject *>(object)); }
};

/** Type of reference (#SLE_REF, #SLE_CONDREF). */
enum SLRefType {
	REF_ORDER          =  0, ///< Load/save a reference to an order.
	REF_VEHICLE        =  1, ///< Load/save a reference to a vehicle.
	REF_STATION        =  2, ///< Load/save a reference to a station.
	REF_TOWN           =  3, ///< Load/save a reference to a town.
	REF_VEHICLE_OLD    =  4, ///< Load/save an old-style reference to a vehicle (for pre-4.4 savegames).
	REF_ROADSTOPS      =  5, ///< Load/save a reference to a bus/truck stop.
	REF_ENGINE_RENEWS  =  6, ///< Load/save a reference to an engine renewal (autoreplace).
	REF_CARGO_PACKET   =  7, ///< Load/save a reference to a cargo packet.
	REF_ORDERLIST      =  8, ///< Load/save a reference to an orderlist.
	REF_STORAGE        =  9, ///< Load/save a reference to a persistent storage.
	REF_LINK_GRAPH     = 10, ///< Load/save a reference to a link graph.
	REF_LINK_GRAPH_JOB = 11, ///< Load/save a reference to a link graph job.
};

/**
 * VarTypes is the general bitmasked magic type that tells us
 * certain characteristics about the variable it refers to. For example
 * SLE_FILE_* gives the size(type) as it would be in the savegame and
 * SLE_VAR_* the size(type) as it is in memory during runtime. These are
 * the first 8 bits (0-3 SLE_FILE, 4-7 SLE_VAR).
 * Bits 8-15 are reserved for various flags as explained below
 */
enum VarTypes {
	/* 4 bits allocated a maximum of 16 types for NumberType.
	 * NOTE: the SLE_FILE_NNN values are stored in the savegame! */
	SLE_FILE_END      =  0, ///< Used to mark end-of-header in tables.
	SLE_FILE_I8       =  1,
	SLE_FILE_U8       =  2,
	SLE_FILE_I16      =  3,
	SLE_FILE_U16      =  4,
	SLE_FILE_I32      =  5,
	SLE_FILE_U32      =  6,
	SLE_FILE_I64      =  7,
	SLE_FILE_U64      =  8,
	SLE_FILE_STRINGID =  9, ///< StringID offset into strings-array
	SLE_FILE_STRING   = 10,
	SLE_FILE_STRUCT   = 11,
	/* 4 more possible file-primitives */

	SLE_FILE_TYPE_MASK = 0xf, ///< Mask to get the file-type (and not any flags).
	SLE_FILE_HAS_LENGTH_FIELD = 1 << 4, ///< Bit stored in savegame to indicate field has a length field for each entry.

	/* 4 bits allocated a maximum of 16 types for NumberType */
	SLE_VAR_BL    =  0 << 4,
	SLE_VAR_I8    =  1 << 4,
	SLE_VAR_U8    =  2 << 4,
	SLE_VAR_I16   =  3 << 4,
	SLE_VAR_U16   =  4 << 4,
	SLE_VAR_I32   =  5 << 4,
	SLE_VAR_U32   =  6 << 4,
	SLE_VAR_I64   =  7 << 4,
	SLE_VAR_U64   =  8 << 4,
	SLE_VAR_NULL  =  9 << 4, ///< useful to write zeros in savegame.
	SLE_VAR_STRB  = 10 << 4, ///< string (with pre-allocated buffer)
	SLE_VAR_STR   = 12 << 4, ///< string pointer
	SLE_VAR_STRQ  = 13 << 4, ///< string pointer enclosed in quotes
	SLE_VAR_NAME  = 14 << 4, ///< old custom name to be converted to a char pointer
	/* 1 more possible memory-primitives */

	/* Shortcut values */
	SLE_VAR_CHAR = SLE_VAR_I8,

	/* Default combinations of variables. As savegames change, so can variables
	 * and thus it is possible that the saved value and internal size do not
	 * match and you need to specify custom combo. The defaults are listed here */
	SLE_BOOL         = SLE_FILE_I8  | SLE_VAR_BL,
	SLE_INT8         = SLE_FILE_I8  | SLE_VAR_I8,
	SLE_UINT8        = SLE_FILE_U8  | SLE_VAR_U8,
	SLE_INT16        = SLE_FILE_I16 | SLE_VAR_I16,
	SLE_UINT16       = SLE_FILE_U16 | SLE_VAR_U16,
	SLE_INT32        = SLE_FILE_I32 | SLE_VAR_I32,
	SLE_UINT32       = SLE_FILE_U32 | SLE_VAR_U32,
	SLE_INT64        = SLE_FILE_I64 | SLE_VAR_I64,
	SLE_UINT64       = SLE_FILE_U64 | SLE_VAR_U64,
	SLE_CHAR         = SLE_FILE_I8  | SLE_VAR_CHAR,
	SLE_STRINGID     = SLE_FILE_STRINGID | SLE_VAR_U32,
	SLE_STRINGBUF    = SLE_FILE_STRING   | SLE_VAR_STRB,
	SLE_STRING       = SLE_FILE_STRING   | SLE_VAR_STR,
	SLE_STRINGQUOTE  = SLE_FILE_STRING   | SLE_VAR_STRQ,
	SLE_NAME         = SLE_FILE_STRINGID | SLE_VAR_NAME,

	/* Shortcut values */
	SLE_UINT  = SLE_UINT32,
	SLE_INT   = SLE_INT32,
	SLE_STRB  = SLE_STRINGBUF,
	SLE_STR   = SLE_STRING,
	SLE_STRQ  = SLE_STRINGQUOTE,

	/* 8 bits allocated for a maximum of 8 flags
	 * Flags directing saving/loading of a variable */
	SLF_ALLOW_CONTROL   = 1 << 8, ///< Allow control codes in the strings.
	SLF_ALLOW_NEWLINE   = 1 << 9, ///< Allow new lines in the strings.
};

typedef uint32 VarType;

/** Type of data saved. */
enum SaveLoadType : byte {
	SL_VAR         =  0, ///< Save/load a variable.
	SL_REF         =  1, ///< Save/load a reference.
	SL_STRUCT      =  2, ///< Save/load a struct.

	SL_STR         =  3, ///< Save/load a string.
	SL_STDSTR      =  4, ///< Save/load a \c std::string.

	SL_ARR         =  5, ///< Save/load a fixed-size array of #SL_VAR elements.
	SL_DEQUE       =  6, ///< Save/load a deque of #SL_VAR elements.
	SL_VECTOR      =  7, ///< Save/load a vector of #SL_VAR elements.
	SL_REFLIST     =  8, ///< Save/load a list of #SL_REF elements.
	SL_STRUCTLIST  =  9, ///< Save/load a list of structs.

	SL_SAVEBYTE    = 10, ///< Save (but not load) a byte.
	SL_NULL        = 11, ///< Save null-bytes and load to nowhere.
};

typedef void *SaveLoadAddrProc(void *base, size_t extra);

/** SaveLoad type struct. Do NOT use this directly but use the SLE_ macros defined just below! */
struct SaveLoad {
	std::string name;    ///< Name of this field (optional, used for tables).
	SaveLoadType cmd;    ///< the action to take with the saved/loaded type, All types need different action
	VarType conv;        ///< type of the variable to be saved, int
	uint16 length;       ///< (conditional) length of the variable (eg. arrays) (max array size is 65536 elements)
	SaveLoadVersion version_from;   ///< save/load the variable starting from this savegame version
	SaveLoadVersion version_to;     ///< save/load the variable until this savegame version
	size_t size;                    ///< the sizeof size.
	SaveLoadAddrProc *address_proc; ///< callback proc the get the actual variable address in memory
	size_t extra_data;              ///< extra data for the callback proc
	std::shared_ptr<SaveLoadHandler> handler; ///< Custom handler for Save/Load procs.
};

/**
 * SaveLoad information for backwards compatibility.
 *
 * At SLV_SETTINGS_NAME a new method of keeping track of fields in a savegame
 * was added, where the order of fields is no longer important. For older
 * savegames we still need to know the correct order. This struct is the glue
 * to make that happen.
 */
struct SaveLoadCompat {
	std::string name;             ///< Name of the field.
	uint16 length;                ///< Length of the NULL field.
	SaveLoadVersion version_from; ///< Save/load the variable starting from this savegame version.
	SaveLoadVersion version_to;   ///< Save/load the variable until this savegame version.
};

/**
 * Storage of simple variables, references (pointers), and arrays.
 * @param cmd      Load/save type. @see SaveLoadType
 * @param base     Name of the class or struct containing the variable.
 * @param variable Name of the variable in the class or struct referenced by \a base.
 * @param type     Storage of the data in memory and in the savegame.
 * @param from     First savegame version that has the field.
 * @param to       Last savegame version that has the field.
 * @param extra    Extra data to pass to the address callback function.
 * @note In general, it is better to use one of the SLE_* macros below.
 */
#define SLE_GENERAL(cmd, base, variable, type, length, from, to, extra) SaveLoad {#variable, cmd, type, length, from, to, cpp_sizeof(base, variable), [] (void *b, size_t) -> void * { assert(b != nullptr); return const_cast<void *>(static_cast<const void *>(std::addressof(static_cast<base *>(b)->variable))); }, extra, nullptr}

/**
 * Storage of a variable in some savegame versions.
 * @param base     Name of the class or struct containing the variable.
 * @param variable Name of the variable in the class or struct referenced by \a base.
 * @param type     Storage of the data in memory and in the savegame.
 * @param from     First savegame version that has the field.
 * @param to       Last savegame version that has the field.
 */
#define SLE_CONDVAR(base, variable, type, from, to) SLE_GENERAL(SL_VAR, base, variable, type, 0, from, to, 0)

/**
 * Storage of a reference in some savegame versions.
 * @param base     Name of the class or struct containing the variable.
 * @param variable Name of the variable in the class or struct referenced by \a base.
 * @param type     Type of the reference, a value from #SLRefType.
 * @param from     First savegame version that has the field.
 * @param to       Last savegame version that has the field.
 */
#define SLE_CONDREF(base, variable, type, from, to) SLE_GENERAL(SL_REF, base, variable, type, 0, from, to, 0)

/**
 * Storage of a fixed-size array of #SL_VAR elements in some savegame versions.
 * @param base     Name of the class or struct containing the array.
 * @param variable Name of the variable in the class or struct referenced by \a base.
 * @param type     Storage of the data in memory and in the savegame.
 * @param length   Number of elements in the array.
 * @param from     First savegame version that has the array.
 * @param to       Last savegame version that has the array.
 */
#define SLE_CONDARR(base, variable, type, length, from, to) SLE_GENERAL(SL_ARR, base, variable, type, length, from, to, 0)

/**
 * Storage of a string in some savegame versions.
 * @param base     Name of the class or struct containing the string.
 * @param variable Name of the variable in the class or struct referenced by \a base.
 * @param type     Storage of the data in memory and in the savegame.
 * @param length   Number of elements in the string (only used for fixed size buffers).
 * @param from     First savegame version that has the string.
 * @param to       Last savegame version that has the string.
 */
#define SLE_CONDSTR(base, variable, type, length, from, to) SLE_GENERAL(SL_STR, base, variable, type, length, from, to, 0)

/**
 * Storage of a \c std::string in some savegame versions.
 * @param base     Name of the class or struct containing the string.
 * @param variable Name of the variable in the class or struct referenced by \a base.
 * @param type     Storage of the data in memory and in the savegame.
 * @param from     First savegame version that has the string.
 * @param to       Last savegame version that has the string.
 */
#define SLE_CONDSSTR(base, variable, type, from, to) SLE_GENERAL(SL_STDSTR, base, variable, type, 0, from, to, 0)

/**
 * Storage of a list of #SL_REF elements in some savegame versions.
 * @param base     Name of the class or struct containing the list.
 * @param variable Name of the variable in the class or struct referenced by \a base.
 * @param type     Storage of the data in memory and in the savegame.
 * @param from     First savegame version that has the list.
 * @param to       Last savegame version that has the list.
 */
#define SLE_CONDREFLIST(base, variable, type, from, to) SLE_GENERAL(SL_REFLIST, base, variable, type, 0, from, to, 0)

/**
 * Storage of a deque of #SL_VAR elements in some savegame versions.
 * @param base     Name of the class or struct containing the list.
 * @param variable Name of the variable in the class or struct referenced by \a base.
 * @param type     Storage of the data in memory and in the savegame.
 * @param from     First savegame version that has the list.
 * @param to       Last savegame version that has the list.
 */
#define SLE_CONDDEQUE(base, variable, type, from, to) SLE_GENERAL(SL_DEQUE, base, variable, type, 0, from, to, 0)

/**
 * Storage of a variable in every version of a savegame.
 * @param base     Name of the class or struct containing the variable.
 * @param variable Name of the variable in the class or struct referenced by \a base.
 * @param type     Storage of the data in memory and in the savegame.
 */
#define SLE_VAR(base, variable, type) SLE_CONDVAR(base, variable, type, SL_MIN_VERSION, SL_MAX_VERSION)

/**
 * Storage of a reference in every version of a savegame.
 * @param base     Name of the class or struct containing the variable.
 * @param variable Name of the variable in the class or struct referenced by \a base.
 * @param type     Type of the reference, a value from #SLRefType.
 */
#define SLE_REF(base, variable, type) SLE_CONDREF(base, variable, type, SL_MIN_VERSION, SL_MAX_VERSION)

/**
 * Storage of fixed-size array of #SL_VAR elements in every version of a savegame.
 * @param base     Name of the class or struct containing the array.
 * @param variable Name of the variable in the class or struct referenced by \a base.
 * @param type     Storage of the data in memory and in the savegame.
 * @param length   Number of elements in the array.
 */
#define SLE_ARR(base, variable, type, length) SLE_CONDARR(base, variable, type, length, SL_MIN_VERSION, SL_MAX_VERSION)

/**
 * Storage of a string in every savegame version.
 * @param base     Name of the class or struct containing the string.
 * @param variable Name of the variable in the class or struct referenced by \a base.
 * @param type     Storage of the data in memory and in the savegame.
 * @param length   Number of elements in the string (only used for fixed size buffers).
 */
#define SLE_STR(base, variable, type, length) SLE_CONDSTR(base, variable, type, length, SL_MIN_VERSION, SL_MAX_VERSION)

/**
 * Storage of a \c std::string in every savegame version.
 * @param base     Name of the class or struct containing the string.
 * @param variable Name of the variable in the class or struct referenced by \a base.
 * @param type     Storage of the data in memory and in the savegame.
 */
#define SLE_SSTR(base, variable, type) SLE_CONDSSTR(base, variable, type, SL_MIN_VERSION, SL_MAX_VERSION)

/**
 * Storage of a list of #SL_REF elements in every savegame version.
 * @param base     Name of the class or struct containing the list.
 * @param variable Name of the variable in the class or struct referenced by \a base.
 * @param type     Storage of the data in memory and in the savegame.
 */
#define SLE_REFLIST(base, variable, type) SLE_CONDREFLIST(base, variable, type, SL_MIN_VERSION, SL_MAX_VERSION)

/**
 * Empty space in every savegame version.
 * @param length Length of the empty space.
 */
#define SLE_NULL(length) SLE_CONDNULL(length, SL_MIN_VERSION, SL_MAX_VERSION)

/**
 * Empty space in some savegame versions.
 * @param length Length of the empty space.
 * @param from   First savegame version that has the empty space.
 * @param to     Last savegame version that has the empty space.
 */
#define SLE_CONDNULL(length, from, to) SaveLoad {"", SL_NULL, SLE_FILE_U8 | SLE_VAR_NULL, length, from, to, 0, nullptr, 0, nullptr}

/**
 * Only write byte during saving; never read it during loading.
 * When using SLE_SAVEBYTE you will have to read this byte before the table
 * this is in is read. This also means SLE_SAVEBYTE can only be used at the
 * top of a chunk.
 * This is intended to be used to indicate what type of entry this is in a
 * list of entries.
 * @param base     Name of the class or struct containing the variable.
 * @param variable Name of the variable in the class or struct referenced by \a base.
 */
#define SLE_SAVEBYTE(base, variable) SLE_GENERAL(SL_SAVEBYTE, base, variable, 0, 0, SL_MIN_VERSION, SL_MAX_VERSION, 0)

/**
 * Storage of global simple variables, references (pointers), and arrays.
 * @param name     The name of the field.
 * @param cmd      Load/save type. @see SaveLoadType
 * @param variable Name of the global variable.
 * @param type     Storage of the data in memory and in the savegame.
 * @param from     First savegame version that has the field.
 * @param to       Last savegame version that has the field.
 * @param extra    Extra data to pass to the address callback function.
 * @note In general, it is better to use one of the SLEG_* macros below.
 */
#define SLEG_GENERAL(name, cmd, variable, type, length, from, to, extra) SaveLoad {name, cmd, type, length, from, to, sizeof(variable), [] (void *, size_t) -> void * { return static_cast<void *>(std::addressof(variable)); }, extra, nullptr}

/**
 * Storage of a global variable in some savegame versions.
 * @param name     The name of the field.
 * @param variable Name of the global variable.
 * @param type     Storage of the data in memory and in the savegame.
 * @param from     First savegame version that has the field.
 * @param to       Last savegame version that has the field.
 */
#define SLEG_CONDVAR(name, variable, type, from, to) SLEG_GENERAL(name, SL_VAR, variable, type, 0, from, to, 0)

/**
 * Storage of a global reference in some savegame versions.
 * @param name     The name of the field.
 * @param variable Name of the global variable.
 * @param type     Storage of the data in memory and in the savegame.
 * @param from     First savegame version that has the field.
 * @param to       Last savegame version that has the field.
 */
#define SLEG_CONDREF(name, variable, type, from, to) SLEG_GENERAL(name, SL_REF, variable, type, 0, from, to, 0)

/**
 * Storage of a global fixed-size array of #SL_VAR elements in some savegame versions.
 * @param name     The name of the field.
 * @param variable Name of the global variable.
 * @param type     Storage of the data in memory and in the savegame.
 * @param length   Number of elements in the array.
 * @param from     First savegame version that has the array.
 * @param to       Last savegame version that has the array.
 */
#define SLEG_CONDARR(name, variable, type, length, from, to) SLEG_GENERAL(name, SL_ARR, variable, type, length, from, to, 0)

/**
 * Storage of a global string in some savegame versions.
 * @param name     The name of the field.
 * @param variable Name of the global variable.
 * @param type     Storage of the data in memory and in the savegame.
 * @param length   Number of elements in the string (only used for fixed size buffers).
 * @param from     First savegame version that has the string.
 * @param to       Last savegame version that has the string.
 */
#define SLEG_CONDSTR(name, variable, type, length, from, to) SLEG_GENERAL(name, SL_STR, variable, type, length, from, to, 0)

/**
 * Storage of a global \c std::string in some savegame versions.
 * @param name     The name of the field.
 * @param variable Name of the global variable.
 * @param type     Storage of the data in memory and in the savegame.
 * @param from     First savegame version that has the string.
 * @param to       Last savegame version that has the string.
 */
#define SLEG_CONDSSTR(name, variable, type, from, to) SLEG_GENERAL(name, SL_STDSTR, variable, type, 0, from, to, 0)

/**
 * Storage of a structs in some savegame versions.
 * @param name     The name of the field.
 * @param handler  SaveLoadHandler for the structs.
 * @param from     First savegame version that has the struct.
 * @param to       Last savegame version that has the struct.
 */
#define SLEG_CONDSTRUCT(name, handler, from, to) SaveLoad {name, SL_STRUCT, 0, 0, from, to, 0, nullptr, 0, std::make_shared<handler>()}

/**
 * Storage of a global reference list in some savegame versions.
 * @param name     The name of the field.
 * @param variable Name of the global variable.
 * @param type     Storage of the data in memory and in the savegame.
 * @param from     First savegame version that has the list.
 * @param to       Last savegame version that has the list.
 */
#define SLEG_CONDREFLIST(name, variable, type, from, to) SLEG_GENERAL(name, SL_REFLIST, variable, type, 0, from, to, 0)

/**
 * Storage of a global vector of #SL_VAR elements in some savegame versions.
 * @param name     The name of the field.
 * @param variable Name of the global variable.
 * @param type     Storage of the data in memory and in the savegame.
 * @param from     First savegame version that has the list.
 * @param to       Last savegame version that has the list.
 */
#define SLEG_CONDVECTOR(name, variable, type, from, to) SLEG_GENERAL(name, SL_VECTOR, variable, type, 0, from, to, 0)

/**
 * Storage of a list of structs in some savegame versions.
 * @param name     The name of the field.
 * @param handler  SaveLoadHandler for the list of structs.
 * @param from     First savegame version that has the list.
 * @param to       Last savegame version that has the list.
 */
#define SLEG_CONDSTRUCTLIST(name, handler, from, to) SaveLoad {name, SL_STRUCTLIST, 0, 0, from, to, 0, nullptr, 0, std::make_shared<handler>()}

/**
 * Storage of a global variable in every savegame version.
 * @param name     The name of the field.
 * @param variable Name of the global variable.
 * @param type     Storage of the data in memory and in the savegame.
 */
#define SLEG_VAR(name, variable, type) SLEG_CONDVAR(name, variable, type, SL_MIN_VERSION, SL_MAX_VERSION)

/**
 * Storage of a global reference in every savegame version.
 * @param name     The name of the field.
 * @param variable Name of the global variable.
 * @param type     Storage of the data in memory and in the savegame.
 */
#define SLEG_REF(name, variable, type) SLEG_CONDREF(name, variable, type, SL_MIN_VERSION, SL_MAX_VERSION)

/**
 * Storage of a global fixed-size array of #SL_VAR elements in every savegame version.
 * @param name     The name of the field.
 * @param variable Name of the global variable.
 * @param type     Storage of the data in memory and in the savegame.
 */
#define SLEG_ARR(name, variable, type) SLEG_CONDARR(name, variable, type, lengthof(variable), SL_MIN_VERSION, SL_MAX_VERSION)

/**
 * Storage of a global string in every savegame version.
 * @param name     The name of the field.
 * @param variable Name of the global variable.
 * @param type     Storage of the data in memory and in the savegame.
 */
#define SLEG_STR(name, variable, type) SLEG_CONDSTR(name, variable, type, sizeof(variable), SL_MIN_VERSION, SL_MAX_VERSION)

/**
 * Storage of a global \c std::string in every savegame version.
 * @param name     The name of the field.
 * @param variable Name of the global variable.
 * @param type     Storage of the data in memory and in the savegame.
 */
#define SLEG_SSTR(name, variable, type) SLEG_CONDSSTR(name, variable, type, SL_MIN_VERSION, SL_MAX_VERSION)

/**
 * Storage of a structs in every savegame version.
 * @param name     The name of the field.
 * @param handler SaveLoadHandler for the structs.
 */
#define SLEG_STRUCT(name, handler) SLEG_CONDSTRUCT(name, handler, SL_MIN_VERSION, SL_MAX_VERSION)

/**
 * Storage of a global reference list in every savegame version.
 * @param name     The name of the field.
 * @param variable Name of the global variable.
 * @param type     Storage of the data in memory and in the savegame.
 */
#define SLEG_REFLIST(name, variable, type) SLEG_CONDREFLIST(name, variable, type, SL_MIN_VERSION, SL_MAX_VERSION)

/**
 * Storage of a global vector of #SL_VAR elements in every savegame version.
 * @param name     The name of the field.
 * @param variable Name of the global variable.
 * @param type     Storage of the data in memory and in the savegame.
 */
#define SLEG_VECTOR(name, variable, type) SLEG_CONDVECTOR(name, variable, type, SL_MIN_VERSION, SL_MAX_VERSION)

/**
 * Storage of a list of structs in every savegame version.
 * @param name    The name of the field.
 * @param handler SaveLoadHandler for the list of structs.
 */
#define SLEG_STRUCTLIST(name, handler) SLEG_CONDSTRUCTLIST(name, handler, SL_MIN_VERSION, SL_MAX_VERSION)

/**
 * Empty global space in some savegame versions.
 * @param length Length of the empty space.
 * @param from   First savegame version that has the empty space.
 * @param to     Last savegame version that has the empty space.
 */
#define SLEG_CONDNULL(length, from, to) SaveLoad {"", SL_NULL, SLE_FILE_U8 | SLE_VAR_NULL, length, from, to, 0, nullptr, 0, nullptr}

/**
 * Field name where the real SaveLoad can be located.
 * @param name The name of the field.
 */
#define SLC_VAR(name) {name, 0, SL_MIN_VERSION, SL_MAX_VERSION}

/**
 * Empty space in every savegame version.
 * @param length Length of the empty space.
 * @param from   First savegame version that has the empty space.
 * @param to     Last savegame version that has the empty space.
 */
#define SLC_NULL(length, from, to) {{}, length, from, to}

/** End marker of compat variables save or load. */
#define SLC_END() {{}, 0, SL_MIN_VERSION, SL_MIN_VERSION}

/**
 * Checks whether the savegame is below \a major.\a minor.
 * @param major Major number of the version to check against.
 * @param minor Minor number of the version to check against. If \a minor is 0 or not specified, only the major number is checked.
 * @return Savegame version is earlier than the specified version.
 */
static inline bool IsSavegameVersionBefore(SaveLoadVersion major, byte minor = 0)
{
	extern SaveLoadVersion _sl_version;
	extern byte            _sl_minor_version;
	return _sl_version < major || (minor > 0 && _sl_version == major && _sl_minor_version < minor);
}

/**
 * Checks whether the savegame is below or at \a major. This should be used to repair data from existing
 * savegames which is no longer corrupted in new savegames, but for which otherwise no savegame
 * bump is required.
 * @param major Major number of the version to check against.
 * @return Savegame version is at most the specified version.
 */
static inline bool IsSavegameVersionUntil(SaveLoadVersion major)
{
	extern SaveLoadVersion _sl_version;
	return _sl_version <= major;
}

/**
 * Checks if some version from/to combination falls within the range of the
 * active savegame version.
 * @param version_from Inclusive savegame version lower bound.
 * @param version_to   Exclusive savegame version upper bound. SL_MAX_VERSION if no upper bound.
 * @return Active savegame version falls within the given range.
 */
static inline bool SlIsObjectCurrentlyValid(SaveLoadVersion version_from, SaveLoadVersion version_to)
{
	extern const SaveLoadVersion SAVEGAME_VERSION;
	return version_from <= SAVEGAME_VERSION && SAVEGAME_VERSION < version_to;
}

/**
 * Get the NumberType of a setting. This describes the integer type
 * as it is represented in memory
 * @param type VarType holding information about the variable-type
 * @return the SLE_VAR_* part of a variable-type description
 */
static inline VarType GetVarMemType(VarType type)
{
	return type & 0xF0; // GB(type, 4, 4) << 4;
}

/**
 * Get the FileType of a setting. This describes the integer type
 * as it is represented in a savegame/file
 * @param type VarType holding information about the file-type
 * @return the SLE_FILE_* part of a variable-type description
 */
static inline VarType GetVarFileType(VarType type)
{
	return type & 0xF; // GB(type, 0, 4);
}

/**
 * Check if the given saveload type is a numeric type.
 * @param conv the type to check
 * @return True if it's a numeric type.
 */
static inline bool IsNumericType(VarType conv)
{
	return GetVarMemType(conv) <= SLE_VAR_U64;
}

/**
 * Get the address of the variable. Null-variables don't have an address,
 * everything else has a callback function that returns the address based
 * on the saveload data and the current object for non-globals.
 */
static inline void *GetVariableAddress(const void *object, const SaveLoad &sld)
{
	/* Entry is a null-variable, mostly used to read old savegames etc. */
	if (GetVarMemType(sld.conv) == SLE_VAR_NULL) {
		assert(sld.address_proc == nullptr);
		return nullptr;
	}

	/* Everything else should be a non-null pointer. */
	assert(sld.address_proc != nullptr);
	return sld.address_proc(const_cast<void *>(object), sld.extra_data);
}

int64 ReadValue(const void *ptr, VarType conv);
void WriteValue(void *ptr, VarType conv, int64 val);

void SlSetArrayIndex(uint index);
int SlIterateArray();

void SlSetStructListLength(size_t length);
size_t SlGetStructListLength(size_t limit);

void SlAutolength(AutolengthProc *proc, void *arg);
size_t SlGetFieldLength();
void SlSetLength(size_t length);
size_t SlCalcObjMemberLength(const void *object, const SaveLoad &sld);
size_t SlCalcObjLength(const void *object, const SaveLoadTable &slt);

byte SlReadByte();
void SlWriteByte(byte b);

void SlGlobList(const SaveLoadTable &slt);
void SlCopy(void *object, size_t length, VarType conv);
std::vector<SaveLoad> SlTableHeader(const SaveLoadTable &slt);
std::vector<SaveLoad> SlCompatTableHeader(const SaveLoadTable &slt, const SaveLoadCompatTable &slct);
void SlObject(void *object, const SaveLoadTable &slt);
void NORETURN SlError(StringID string, const char *extra_msg = nullptr);
void NORETURN SlErrorCorrupt(const char *msg);
void NORETURN SlErrorCorruptFmt(const char *format, ...) WARN_FORMAT(1, 2);

bool SaveloadCrashWithMissingNewGRFs();

/**
 * Read in bytes from the file/data structure but don't do
 * anything with them, discarding them in effect
 * @param length The amount of bytes that is being treated this way
 */
static inline void SlSkipBytes(size_t length)
{
	for (; length != 0; length--) SlReadByte();
}

extern std::string _savegame_format;
extern bool _do_autosave;

#endif /* SAVELOAD_H */