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 "statusbar_gui.h"

    34

#include <list>

    35

#include "gamelog.h"

    36

    37

#include "table/strings.h"

    38

    39

extern const uint16 SAVEGAME_VERSION = NEWGRF_AIRPORTS_SAVEGAME;

    40

    41

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

    42

    43

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

    44

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

    45

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

    46

    47

typedef void WriterProc(size_t len);

    48

typedef size_t ReaderProc();

    49

    50

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

    51

static struct {

    52

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

    53

	byte need_length;                    ///< ???

    54

	byte block_mode;                     ///< ???

    55

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

    56

    57

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

    58

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

    59

    60

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

    61

    62

	WriterProc *write_bytes;             ///< savegame writer function

    63

	ReaderProc *read_bytes;              ///< savegame loader function

    64

    65

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

    66

    67

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

    68

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

    69

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

    70

    71

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

    72

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

    73

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

    74

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

    75

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

    76

    77

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

    78

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

    79

	char *extra_msg;                     ///< the error message

    80

} _sl;

    81

    82

    83

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

    84

    85

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

    86

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

    87

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

    88

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

    89

{

    90

	_sl.error_str = string;

    91

	free(_sl.extra_msg);

    92

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

    93

	throw std::exception();

    94

}

    95

    96

typedef void (*AsyncSaveFinishProc)();

    97

static AsyncSaveFinishProc _async_save_finish = NULL;

    99

   100

/**

   101

 * Called by save thread to tell we finished saving.

   102

 */

   103

static void SetAsyncSaveFinish(AsyncSaveFinishProc proc)

   104

{

   105

	if (_exit_game) return;

   106

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

   107

   108

	_async_save_finish = proc;

   109

}

   110

   111

/**

   112

 * Handle async save finishes.

   113

 */

   114

void ProcessAsyncSaveFinish()

   115

{

   116

	if (_async_save_finish == NULL) return;

   117

   118

	_async_save_finish();

   119

   120

	_async_save_finish = NULL;

   127

}

   128

   129

/**

   130

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

   131

 */

   132

static void SlReadFill()

   133

{

   134

	size_t len = _sl.read_bytes();

   135

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

   136

   137

	_sl.bufp = _sl.buf;

   138

	_sl.bufe = _sl.buf + len;

   139

	_sl.offs_base += len;

   140

}

   141

   142

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

   143

   144

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

   145

 * as it appears in memory. See VarTypes

   146

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

   147

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

   148

static inline byte SlCalcConvMemLen(VarType conv)

   149

{

   150

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

   151

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

   152

	assert(length < lengthof(conv_mem_size));

   153

	return conv_mem_size[length];

   154

}

   155

   156

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

   157

 * as it appears in a saved game. See VarTypes

   158

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

   159

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

   160

static inline byte SlCalcConvFileLen(VarType conv)

   161

{

   162

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

   163

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

   164

	assert(length < lengthof(conv_file_size));

   165

	return conv_file_size[length];

   166

}

   167

   168

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

   169

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

   170

   171

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

   172

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

   173

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

   174

 */

   175

static void SlWriteFill()

   176

{

   177

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

   178

	if (_sl.bufp != NULL) {

   179

		uint len = _sl.bufp - _sl.buf;

   180

		_sl.offs_base += len;

   181

		if (len) _sl.write_bytes(len);

   182

	}

   183

   184

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

   185

	 * to start reading in more data */

   186

	_sl.bufp = _sl.buf;

   187

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

   188

}

   189

   190

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

   191

 * flush it to its final destination

   192

 * @return return the read byte from file

   193

 */

   194

static inline byte SlReadByteInternal()

   195

{

   196

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

   197

	return *_sl.bufp++;

   198

}

   199

   200

/** Wrapper for SlReadByteInternal */

   201

byte SlReadByte() {return SlReadByteInternal();}

   202

   203

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

   204

 * flush it to its destination (file)

   205

 * @param b the byte that is currently written

   206

 */

   207

static inline void SlWriteByteInternal(byte b)

   208

{

   209

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

   210

	*_sl.bufp++ = b;

   211

}

   212

   213

/** Wrapper for SlWriteByteInternal */

   214

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

   215

   216

static inline int SlReadUint16()

   217

{

   218

	int x = SlReadByte() << 8;

   219

	return x | SlReadByte();

   220

}

   221

   222

static inline uint32 SlReadUint32()

   223

{

   224

	uint32 x = SlReadUint16() << 16;

   225

	return x | SlReadUint16();

   226

}

   227

   228

static inline uint64 SlReadUint64()

   229

{

   230

	uint32 x = SlReadUint32();

   231

	uint32 y = SlReadUint32();

   232

	return (uint64)x << 32 | y;

   233

}

   234

   235

static inline void SlWriteUint16(uint16 v)

   236

{

   237

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

   238

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

   239

}

   240

   241

static inline void SlWriteUint32(uint32 v)

   242

{

   243

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

   244

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

   245

}

   246

   247

static inline void SlWriteUint64(uint64 x)

   248

{

   249

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

   250

	SlWriteUint32((uint32)x);

   251

}

   252

   253

/**

   254

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

   255

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

   256

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

   257

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

   258

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

   259

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

   260

 * @return Return the value of the index

   261

 */

   262

static uint SlReadSimpleGamma()

   263

{

   264

	uint i = SlReadByte();

   265

	if (HasBit(i, 7)) {

   266

		i &= ~0x80;

   267

		if (HasBit(i, 6)) {

   268

			i &= ~0x40;

   269

			if (HasBit(i, 5)) {

   270

				i &= ~0x20;

   271

				if (HasBit(i, 4))

   272

					SlError(STR_GAME_SAVELOAD_ERROR_BROKEN_SAVEGAME, "Unsupported gamma");

   273

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

   274

			}

   275

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

   276

		}

   277

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

   278

	}

   279

	return i;

   280

}

   281

   282

/**

   283

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

   284

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

   285

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

   286

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

   287

 * 0xxxxxxx

   288

 * 10xxxxxx xxxxxxxx

   289

 * 110xxxxx xxxxxxxx xxxxxxxx

   290

 * 1110xxxx xxxxxxxx xxxxxxxx xxxxxxxx

   291

 * @param i Index being written

   292

 */

   293

   294

static void SlWriteSimpleGamma(size_t i)

   295

{

   296

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

   297

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

   298

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

   299

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

   300

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

   301

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

   302

			} else {

   303

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

   304

			}

   305

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

   306

		} else {

   307

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

   308

		}

   309

	}

   310

	SlWriteByte((byte)i);

   311

}

   312

   313

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

   314

static inline uint SlGetGammaLength(size_t i)

   315

{

   316

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

   317

}

   318

   319

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

   320

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

   321

   322

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

   323

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

   324

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

   325

   326

void SlSetArrayIndex(uint index)

   327

{

   328

	_sl.need_length = NL_WANTLENGTH;

   329

	_sl.array_index = index;

   330

}

   331

   332

static size_t _next_offs;

   333

   334

/**

   335

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

   336

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

   337

 */

   338

int SlIterateArray()

   339

{

   340

	int index;

   341

   342

	/* After reading in the whole array inside the loop

   343

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

   344

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

   345

   346

	while (true) {

   347

		uint length = SlReadArrayLength();

   348

		if (length == 0) {

   349

			_next_offs = 0;

   350

			return -1;

   351

		}

   352

   353

		_sl.obj_len = --length;

   354

		_next_offs = SlGetOffs() + length;

   355

   356

		switch (_sl.block_mode) {

   357

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

   358

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

   359

		default:

   360

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

   361

			return -1; // error

   362

		}

   363

   364

		if (length != 0) return index;

   365

	}

   366

}

   367

   368

/**

   369

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

   370

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

   371

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

   372

 */

   373

void SlSetLength(size_t length)

   374

{

   375

	assert(_sl.save);

   376

   377

	switch (_sl.need_length) {

   378

	case NL_WANTLENGTH:

   379

		_sl.need_length = NL_NONE;

   380

		switch (_sl.block_mode) {

   381

		case CH_RIFF:

   382

			/* Ugly encoding of >16M RIFF chunks

   383

			 * The lower 24 bits are normal

   384

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

   385

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

   386

			SlWriteUint32((uint32)((length & 0xFFFFFF) | ((length >> 24) << 28)));

   387

			break;

   388

		case CH_ARRAY:

   389

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

   390

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

   391

				SlWriteArrayLength(1);

   392

			SlWriteArrayLength(length + 1);

   393

			break;

   394

		case CH_SPARSE_ARRAY:

   395

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

   396

			SlWriteSparseIndex(_sl.array_index);

   397

			break;

   398

		default: NOT_REACHED();

   399

		} break;

   400

	case NL_CALCLENGTH:

   401

		_sl.obj_len += (int)length;

   402

		break;

   403

	}

   404

}

   405

   406

/**

   407

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

   408

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

   409

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

   410

 * @param length number of bytes this fast CopyBytes lasts

   411

 */

   412

static void SlCopyBytes(void *ptr, size_t length)

   413

{

   414

	byte *p = (byte*)ptr;

   415

   416

	if (_sl.save) {

   417

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

   418

	} else {

   419

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

   420

	}

   421

}

   422

   423

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

   424

 * anything with them, discarding them in effect

   425

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

   426

 */

   427

static inline void SlSkipBytes(size_t length)

   428

{

   429

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

   430

}

   431

   432

/* Get the length of the current object */

   433

size_t SlGetFieldLength() {return _sl.obj_len;}

   434

   435

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

   436

 * @param ptr pointer to the variable

   437

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

   438

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

   439

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

   440

int64 ReadValue(const void *ptr, VarType conv)

   441

{

   442

	switch (GetVarMemType(conv)) {

   443

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

   444

	case SLE_VAR_I8:  return *(int8*  )ptr;

   445

	case SLE_VAR_U8:  return *(byte*  )ptr;

   446

	case SLE_VAR_I16: return *(int16* )ptr;

   447

	case SLE_VAR_U16: return *(uint16*)ptr;

   448

	case SLE_VAR_I32: return *(int32* )ptr;

   449

	case SLE_VAR_U32: return *(uint32*)ptr;

   450

	case SLE_VAR_I64: return *(int64* )ptr;

   451

	case SLE_VAR_U64: return *(uint64*)ptr;

   452

	case SLE_VAR_NULL:return 0;

   453

	default: NOT_REACHED();

   454

	}

   455

   456

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

   457

	return 0;

   458

}

   459

   460

/** Write the value of a setting

   461

 * @param ptr pointer to the variable

   462

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

   463

 *             with other flags. It is parsed upon read

   464

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

   465

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

   466

{

   467

	switch (GetVarMemType(conv)) {

   468

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

   469

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

   470

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

   471

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

   472

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

   473

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

   474

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

   475

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

   476

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

   477

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

   478

	case SLE_VAR_NULL: break;

   479

	default: NOT_REACHED();

   480

	}

   481

}

   482

   483

/**

   484

 * Handle all conversion and typechecking of variables here.

   485

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

   486

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

   487

 * goes exactly the opposite way

   488

 * @param ptr The object being filled/read

   489

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

   490

 */