1

/* $Id$ */

     2

     3

/** @file saveload.cpp

     4

 * All actions handling saving and loading goes on in this file. The general actions

     5

 * are as follows for saving a game (loading is analogous):

     6

 * <ol>

     7

 * <li>initialize the writer by creating a temporary memory-buffer for it

     8

 * <li>go through all to-be saved elements, each 'chunk' (ChunkHandler) prefixed by a label

     9

 * <li>use their description array (SaveLoad) to know what elements to save and in what version

    10

 *    of the game it was active (used when loading)

    11

 * <li>write all data byte-by-byte to the temporary buffer so it is endian-safe

    12

 * <li>when the buffer is full; flush it to the output (eg save to file) (_sl.buf, _sl.bufp, _sl.bufe)

    13

 * <li>repeat this until everything is done, and flush any remaining output to file

    14

 * </ol>

    15

 */

    16

#include "stdafx.h"

    17

#include "openttd.h"

    18

#include "debug.h"

    19

#include "station_base.h"

    20

#include "thread.h"

    21

#include "town.h"

    22

#include "saveload.h"

    23

#include "network/network.h"

    24

#include "variables.h"

    25

#include "window_func.h"

    26

#include "strings_func.h"

    27

#include "gfx_func.h"

    28

#include "core/alloc_func.hpp"

    29

#include "functions.h"

    30

#include "core/endian_func.hpp"

    31

#include "vehicle_base.h"

    32

#include "autoreplace_base.h"

    33

#include <list>

    34

    35

#include "table/strings.h"

    36

    37

extern const uint16 SAVEGAME_VERSION = 95;

    38

    39

SavegameType _savegame_type; ///< type of savegame we are loading

    40

    41

uint32 _ttdp_version;     ///< version of TTDP savegame (if applicable)

    42

uint16 _sl_version;       ///< the major savegame version identifier

    43

byte   _sl_minor_version; ///< the minor savegame version, DO NOT USE!

    44

    45

typedef void WriterProc(uint len);

    46

typedef uint ReaderProc();

    47

    48

/** The saveload struct, containing reader-writer functions, bufffer, version, etc. */

    49

static struct {

    50

	bool save;                           ///< are we doing a save or a load atm. True when saving

    51

	byte need_length;                    ///< ???

    52

	byte block_mode;                     ///< ???

    53

	bool error;                          ///< did an error occur or not

    54

    55

	int obj_len;                         ///< the length of the current object we are busy with

    56

	int array_index, last_array_index;   ///< in the case of an array, the current and last positions

    57

    58

	uint32 offs_base;                    ///< the offset in number of bytes since we started writing data (eg uncompressed savegame size)

    59

    60

	WriterProc *write_bytes;             ///< savegame writer function

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	ReaderProc *read_bytes;              ///< savegame loader function

    62

    63

	const ChunkHandler* const *chs;      ///< the chunk of data that is being processed atm (vehicles, signs, etc.)

    64

    65

	/* When saving/loading savegames, they are always saved to a temporary memory-place

    66

	 * to be flushed to file (save) or to final place (load) when full. */

    67

	byte *bufp, *bufe;                   ///< bufp(ointer) gives the current position in the buffer bufe(nd) gives the end of the buffer

    68

    69

	/* these 3 may be used by compressor/decompressors. */

    70

	byte *buf;                           ///< pointer to temporary memory to read/write, initialized by SaveLoadFormat->initread/write

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	byte *buf_ori;                       ///< pointer to the original memory location of buf, used to free it afterwards

    72

	uint bufsize;                        ///< the size of the temporary memory *buf

    73

	FILE *fh;                            ///< the file from which is read or written to

    74

    75

	void (*excpt_uninit)();              ///< the function to execute on any encountered error

    76

	StringID error_str;                  ///< the translateable error message to show

    77

	char *extra_msg;                     ///< the error message

    78

} _sl;

    79

    80

    81

enum NeedLengthValues {NL_NONE = 0, NL_WANTLENGTH = 1, NL_CALCLENGTH = 2};

    82

    83

/** Error handler, calls longjmp to simulate an exception.

    84

 * @todo this was used to have a central place to handle errors, but it is

    85

 * pretty ugly, and seriously interferes with any multithreaded approaches */

    86

static void NORETURN SlError(StringID string, const char *extra_msg = NULL)

    87

{

    88

	_sl.error_str = string;

    89

	free(_sl.extra_msg);

    90

	_sl.extra_msg = (extra_msg == NULL) ? NULL : strdup(extra_msg);

    91

	throw std::exception();

    92

}

    93

    94

typedef void (*AsyncSaveFinishProc)();

    95

static AsyncSaveFinishProc _async_save_finish = NULL;

    96

    97

/**

    98

 * Called by save thread to tell we finished saving.

    99

 */

   100

static void SetAsyncSaveFinish(AsyncSaveFinishProc proc)

   101

{

   102

	if (_exit_game) return;

   103

	while (_async_save_finish != NULL) CSleep(10);

   104

   105

	_async_save_finish = proc;

   106

}

   107

   108

/**

   109

 * Handle async save finishes.

   110

 */

   111

void ProcessAsyncSaveFinish()

   112

{

   113

	if (_async_save_finish == NULL) return;

   114

   115

	_async_save_finish();

   116

   117

	_async_save_finish = NULL;

   118

}

   119

   120

/**

   121

 * Fill the input buffer by reading from the file with the given reader

   122

 */

   123

static void SlReadFill()

   124

{

   125

	uint len = _sl.read_bytes();

   126

	if (len == 0) SlError(STR_GAME_SAVELOAD_ERROR_BROKEN_SAVEGAME, "Unexpected end of chunk");

   127

   128

	_sl.bufp = _sl.buf;

   129

	_sl.bufe = _sl.buf + len;

   130

	_sl.offs_base += len;

   131

}

   132

   133

static inline uint32 SlGetOffs() {return _sl.offs_base - (_sl.bufe - _sl.bufp);}

   134

   135

/** Return the size in bytes of a certain type of normal/atomic variable

   136

 * as it appears in memory. See VarTypes

   137

 * @param conv VarType type of variable that is used for calculating the size

   138

 * @return Return the size of this type in bytes */

   139

static inline byte SlCalcConvMemLen(VarType conv)

   140

{

   141

	static const byte conv_mem_size[] = {1, 1, 1, 2, 2, 4, 4, 8, 8, 0};

   142

	byte length = GB(conv, 4, 4);

   143

	assert(length < lengthof(conv_mem_size));

   144

	return conv_mem_size[length];

   145

}

   146

   147

/** Return the size in bytes of a certain type of normal/atomic variable

   148

 * as it appears in a saved game. See VarTypes

   149

 * @param conv VarType type of variable that is used for calculating the size

   150

 * @return Return the size of this type in bytes */

   151

static inline byte SlCalcConvFileLen(VarType conv)

   152

{

   153

	static const byte conv_file_size[] = {1, 1, 2, 2, 4, 4, 8, 8, 2};

   154

	byte length = GB(conv, 0, 4);

   155

	assert(length < lengthof(conv_file_size));

   156

	return conv_file_size[length];

   157

}

   158

   159

/** Return the size in bytes of a reference (pointer) */

   160

static inline size_t SlCalcRefLen() {return CheckSavegameVersion(69) ? 2 : 4;}

   161

   162

/** Flush the output buffer by writing to disk with the given reader.

   163

 * If the buffer pointer has not yet been set up, set it up now. Usually

   164

 * only called when the buffer is full, or there is no more data to be processed

   165

 */

   166

static void SlWriteFill()

   167

{

   168

	/* flush the buffer to disk (the writer) */

   169

	if (_sl.bufp != NULL) {

   170

		uint len = _sl.bufp - _sl.buf;

   171

		_sl.offs_base += len;

   172

		if (len) _sl.write_bytes(len);

   173

	}

   174

   175

	/* All the data from the buffer has been written away, rewind to the beginning

   176

	 * to start reading in more data */

   177

	_sl.bufp = _sl.buf;

   178

	_sl.bufe = _sl.buf + _sl.bufsize;

   179

}

   180

   181

/** Read in a single byte from file. If the temporary buffer is full,

   182

 * flush it to its final destination

   183

 * @return return the read byte from file

   184

 */

   185

static inline byte SlReadByteInternal()

   186

{

   187

	if (_sl.bufp == _sl.bufe) SlReadFill();

   188

	return *_sl.bufp++;

   189

}

   190

   191

/** Wrapper for SlReadByteInternal */

   192

byte SlReadByte() {return SlReadByteInternal();}

   193

   194

/** Write away a single byte from memory. If the temporary buffer is full,

   195

 * flush it to its destination (file)

   196

 * @param b the byte that is currently written

   197

 */

   198

static inline void SlWriteByteInternal(byte b)

   199

{

   200

	if (_sl.bufp == _sl.bufe) SlWriteFill();

   201

	*_sl.bufp++ = b;

   202

}

   203

   204

/** Wrapper for SlWriteByteInternal */

   205

void SlWriteByte(byte b) {SlWriteByteInternal(b);}

   206

   207

static inline int SlReadUint16()

   208

{

   209

	int x = SlReadByte() << 8;

   210

	return x | SlReadByte();

   211

}

   212

   213

static inline uint32 SlReadUint32()

   214

{

   215

	uint32 x = SlReadUint16() << 16;

   216

	return x | SlReadUint16();

   217

}

   218

   219

static inline uint64 SlReadUint64()

   220

{

   221

	uint32 x = SlReadUint32();

   222

	uint32 y = SlReadUint32();

   223

	return (uint64)x << 32 | y;

   224

}

   225

   226

static inline void SlWriteUint16(uint16 v)

   227

{

   228

	SlWriteByte(GB(v, 8, 8));

   229

	SlWriteByte(GB(v, 0, 8));

   230

}

   231

   232

static inline void SlWriteUint32(uint32 v)

   233

{

   234

	SlWriteUint16(GB(v, 16, 16));

   235

	SlWriteUint16(GB(v,  0, 16));

   236

}

   237

   238

static inline void SlWriteUint64(uint64 x)

   239

{

   240

	SlWriteUint32((uint32)(x >> 32));

   241

	SlWriteUint32((uint32)x);

   242

}

   243

   244

/**

   245

 * Read in the header descriptor of an object or an array.

   246

 * If the highest bit is set (7), then the index is bigger than 127

   247

 * elements, so use the next byte to read in the real value.

   248

 * The actual value is then both bytes added with the first shifted

   249

 * 8 bits to the left, and dropping the highest bit (which only indicated a big index).

   250

 * x = ((x & 0x7F) << 8) + SlReadByte();

   251

 * @return Return the value of the index

   252

 */

   253

static uint SlReadSimpleGamma()

   254

{

   255

	uint i = SlReadByte();

   256

	if (HasBit(i, 7)) {

   257

		i &= ~0x80;

   258

		if (HasBit(i, 6)) {

   259

			i &= ~0x40;

   260

			if (HasBit(i, 5)) {

   261

				i &= ~0x20;

   262

				if (HasBit(i, 4))

   263

					SlError(STR_GAME_SAVELOAD_ERROR_BROKEN_SAVEGAME, "Unsupported gamma");

   264

				i = (i << 8) | SlReadByte();

   265

			}

   266

			i = (i << 8) | SlReadByte();

   267

		}

   268

		i = (i << 8) | SlReadByte();

   269

	}

   270

	return i;

   271

}

   272

   273

/**

   274

 * Write the header descriptor of an object or an array.

   275

 * If the element is bigger than 127, use 2 bytes for saving

   276

 * and use the highest byte of the first written one as a notice

   277

 * that the length consists of 2 bytes, etc.. like this:

   278

 * 0xxxxxxx

   279

 * 10xxxxxx xxxxxxxx

   280

 * 110xxxxx xxxxxxxx xxxxxxxx

   281

 * 1110xxxx xxxxxxxx xxxxxxxx xxxxxxxx

   282

 * @param i Index being written

   283

 */

   284

   285

static void SlWriteSimpleGamma(uint i)

   286

{

   287

	if (i >= (1 << 7)) {

   288

		if (i >= (1 << 14)) {

   289

			if (i >= (1 << 21)) {

   290

				assert(i < (1 << 28));

   291

				SlWriteByte((byte)0xE0 | (i >> 24));

   292

				SlWriteByte((byte)(i >> 16));

   293

			} else {

   294

				SlWriteByte((byte)0xC0 | (i >> 16));

   295

			}

   296

			SlWriteByte((byte)(i >> 8));

   297

		} else {

   298

			SlWriteByte((byte)(0x80 | (i >> 8)));

   299

		}

   300

	}

   301

	SlWriteByte(i);

   302

}

   303

   304

/** Return how many bytes used to encode a gamma value */

   305

static inline uint SlGetGammaLength(uint i)

   306

{

   307

	return 1 + (i >= (1 << 7)) + (i >= (1 << 14)) + (i >= (1 << 21));

   308

}

   309

   310

static inline uint SlReadSparseIndex() {return SlReadSimpleGamma();}

   311

static inline void SlWriteSparseIndex(uint index) {SlWriteSimpleGamma(index);}

   312

   313

static inline uint SlReadArrayLength() {return SlReadSimpleGamma();}

   314

static inline void SlWriteArrayLength(uint length) {SlWriteSimpleGamma(length);}

   315

static inline uint SlGetArrayLength(uint length) {return SlGetGammaLength(length);}

   316

   317

void SlSetArrayIndex(uint index)

   318

{

   319

	_sl.need_length = NL_WANTLENGTH;

   320

	_sl.array_index = index;

   321

}

   322

   323

static uint32 _next_offs;

   324

   325

/**

   326

 * Iterate through the elements of an array and read the whole thing

   327

 * @return The index of the object, or -1 if we have reached the end of current block

   328

 */

   329

int SlIterateArray()

   330

{

   331

	int index;

   332

   333

	/* After reading in the whole array inside the loop

   334

	 * we must have read in all the data, so we must be at end of current block. */

   335

	if (_next_offs != 0 && SlGetOffs() != _next_offs) SlError(STR_GAME_SAVELOAD_ERROR_BROKEN_SAVEGAME, "Invalid chunk size");

   336

   337

	while (true) {

   338

		uint length = SlReadArrayLength();

   339

		if (length == 0) {

   340

			_next_offs = 0;

   341

			return -1;

   342

		}

   343

   344

		_sl.obj_len = --length;

   345

		_next_offs = SlGetOffs() + length;

   346

   347

		switch (_sl.block_mode) {

   348

		case CH_SPARSE_ARRAY: index = (int)SlReadSparseIndex(); break;

   349

		case CH_ARRAY:        index = _sl.array_index++; break;

   350

		default:

   351

			DEBUG(sl, 0, "SlIterateArray error");

   352

			return -1; // error

   353

		}

   354

   355

		if (length != 0) return index;

   356

	}

   357

}

   358

   359

/**

   360

 * Sets the length of either a RIFF object or the number of items in an array.

   361

 * This lets us load an object or an array of arbitrary size

   362

 * @param length The length of the sought object/array

   363

 */

   364

void SlSetLength(size_t length)

   365

{

   366

	assert(_sl.save);

   367

   368

	switch (_sl.need_length) {

   369

	case NL_WANTLENGTH:

   370

		_sl.need_length = NL_NONE;

   371

		switch (_sl.block_mode) {

   372

		case CH_RIFF:

   373

			/* Ugly encoding of >16M RIFF chunks

   374

			 * The lower 24 bits are normal

   375

			 * The uppermost 4 bits are bits 24:27 */

   376

			assert(length < (1 << 28));

   377

			SlWriteUint32((length & 0xFFFFFF) | ((length >> 24) << 28));

   378

			break;

   379

		case CH_ARRAY:

   380

			assert(_sl.last_array_index <= _sl.array_index);

   381

			while (++_sl.last_array_index <= _sl.array_index)

   382

				SlWriteArrayLength(1);

   383

			SlWriteArrayLength(length + 1);

   384

			break;

   385

		case CH_SPARSE_ARRAY:

   386

			SlWriteArrayLength(length + 1 + SlGetArrayLength(_sl.array_index)); // Also include length of sparse index.

   387

			SlWriteSparseIndex(_sl.array_index);

   388

			break;

   389

		default: NOT_REACHED();

   390

		} break;

   391

	case NL_CALCLENGTH:

   392

		_sl.obj_len += length;

   393

		break;

   394

	}

   395

}

   396

   397

/**

   398

 * Save/Load bytes. These do not need to be converted to Little/Big Endian

   399

 * so directly write them or read them to/from file

   400

 * @param ptr The source or destination of the object being manipulated

   401

 * @param length number of bytes this fast CopyBytes lasts

   402

 */

   403

static void SlCopyBytes(void *ptr, size_t length)

   404

{

   405

	byte *p = (byte*)ptr;

   406

   407

	if (_sl.save) {

   408

		for (; length != 0; length--) {SlWriteByteInternal(*p++);}

   409

	} else {

   410

		for (; length != 0; length--) {*p++ = SlReadByteInternal();}

   411

	}

   412

}

   413

   414

/** Read in bytes from the file/data structure but don't do

   415

 * anything with them, discarding them in effect

   416

 * @param length The amount of bytes that is being treated this way

   417

 */

   418

static inline void SlSkipBytes(size_t length)

   419

{

   420

	for (; length != 0; length--) SlReadByte();

   421

}

   422

   423

/* Get the length of the current object */

   424

uint SlGetFieldLength() {return _sl.obj_len;}

   425

   426

/** Return a signed-long version of the value of a setting

   427

 * @param ptr pointer to the variable

   428

 * @param conv type of variable, can be a non-clean

   429

 * type, eg one with other flags because it is parsed

   430

 * @return returns the value of the pointer-setting */

   431

int64 ReadValue(const void *ptr, VarType conv)

   432

{

   433

	switch (GetVarMemType(conv)) {

   434

	case SLE_VAR_BL:  return (*(bool*)ptr != 0);

   435

	case SLE_VAR_I8:  return *(int8*  )ptr;

   436

	case SLE_VAR_U8:  return *(byte*  )ptr;

   437

	case SLE_VAR_I16: return *(int16* )ptr;

   438

	case SLE_VAR_U16: return *(uint16*)ptr;

   439

	case SLE_VAR_I32: return *(int32* )ptr;

   440

	case SLE_VAR_U32: return *(uint32*)ptr;

   441

	case SLE_VAR_I64: return *(int64* )ptr;

   442

	case SLE_VAR_U64: return *(uint64*)ptr;

   443

	case SLE_VAR_NULL:return 0;

   444

	default: NOT_REACHED();

   445

	}

   446

   447

	/* useless, but avoids compiler warning this way */

   448

	return 0;

   449

}

   450

   451

/** Write the value of a setting

   452

 * @param ptr pointer to the variable

   453

 * @param conv type of variable, can be a non-clean type, eg

   454

 *             with other flags. It is parsed upon read

   455

 * @param val the new value being given to the variable */

   456

void WriteValue(void *ptr, VarType conv, int64 val)

   457

{

   458

	switch (GetVarMemType(conv)) {

   459

	case SLE_VAR_BL:  *(bool  *)ptr = (val != 0);  break;

   460

	case SLE_VAR_I8:  *(int8  *)ptr = val; break;

   461

	case SLE_VAR_U8:  *(byte  *)ptr = val; break;

   462

	case SLE_VAR_I16: *(int16 *)ptr = val; break;

   463

	case SLE_VAR_U16: *(uint16*)ptr = val; break;

   464

	case SLE_VAR_I32: *(int32 *)ptr = val; break;

   465

	case SLE_VAR_U32: *(uint32*)ptr = val; break;

   466

	case SLE_VAR_I64: *(int64 *)ptr = val; break;

   467

	case SLE_VAR_U64: *(uint64*)ptr = val; break;

   468

	case SLE_VAR_NAME: *(char**)ptr = CopyFromOldName(val); break;

   469

	case SLE_VAR_NULL: break;

   470

	default: NOT_REACHED();

   471

	}

   472

}

   473

   474

/**

   475

 * Handle all conversion and typechecking of variables here.

   476

 * In the case of saving, read in the actual value from the struct

   477

 * and then write them to file, endian safely. Loading a value

   478

 * goes exactly the opposite way

   479

 * @param ptr The object being filled/read

   480

 * @param conv VarType type of the current element of the struct

   481

 */

   482

static void SlSaveLoadConv(void *ptr, VarType conv)

   483

{

   484

	int64 x = 0;

   485

   486

	if (_sl.save) { // SAVE values

   487

		/* Read a value from the struct. These ARE endian safe. */

   488

		x = ReadValue(ptr, conv);

   489

   490

		/* Write the value to the file and check if its value is in the desired range */