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

    38

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

    39

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

    40

    41

typedef void WriterProc(uint len);

    42

typedef uint ReaderProc();

    43

    44

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

    45

static struct {

    46

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

    47

	byte need_length;                    ///< ???

    48

	byte block_mode;                     ///< ???

    49

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

    50

    51

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

    52

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

    53

    54

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

    55

    56

	WriterProc *write_bytes;             ///< savegame writer function

    57

	ReaderProc *read_bytes;              ///< savegame loader function

    58

    59

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

    60

    61

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

    62

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

    63

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

    64

    65

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

    66

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

    67

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

    68

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

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

    70

    71

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

    72

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

    73

	char *extra_msg;                     ///< the error message

    74

} _sl;

    75

    76

    77

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

    78

    79

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

    80

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

    81

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

    82

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

    83

{

    84

	_sl.error_str = string;

    85

	free(_sl.extra_msg);

    86

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

    87

	throw std::exception();

    88

}

    89

    90

typedef void (*AsyncSaveFinishProc)();

    91

static AsyncSaveFinishProc _async_save_finish = NULL;

    92

    93

/**

    94

 * Called by save thread to tell we finished saving.

    95

 */

    96

static void SetAsyncSaveFinish(AsyncSaveFinishProc proc)

    97

{

    98

	if (_exit_game) return;

    99

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

   100

   101

	_async_save_finish = proc;

   102

}

   103

   104

/**

   105

 * Handle async save finishes.

   106

 */

   107

void ProcessAsyncSaveFinish()

   108

{

   109

	if (_async_save_finish == NULL) return;

   110

   111

	_async_save_finish();

   112

   113

	_async_save_finish = NULL;

   114

}

   115

   116

/**

   117

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

   118

 */

   119

static void SlReadFill()

   120

{

   121

	uint len = _sl.read_bytes();

   122

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

   123

   124

	_sl.bufp = _sl.buf;

   125

	_sl.bufe = _sl.buf + len;

   126

	_sl.offs_base += len;

   127

}

   128

   129

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

   130

   131

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

   132

 * as it appears in memory. See VarTypes

   133

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

   134

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

   135

static inline byte SlCalcConvMemLen(VarType conv)

   136

{

   137

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

   138

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

   139

	assert(length < lengthof(conv_mem_size));

   140

	return conv_mem_size[length];

   141

}

   142

   143

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

   144

 * as it appears in a saved game. See VarTypes

   145

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

   146

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

   147

static inline byte SlCalcConvFileLen(VarType conv)

   148

{

   149

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

   150

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

   151

	assert(length < lengthof(conv_file_size));

   152

	return conv_file_size[length];

   153

}

   154

   155

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

   156

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

   157

   158

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

   159

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

   160

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

   161

 */

   162

static void SlWriteFill()

   163

{

   164

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

   165

	if (_sl.bufp != NULL) {

   166

		uint len = _sl.bufp - _sl.buf;

   167

		_sl.offs_base += len;

   168

		if (len) _sl.write_bytes(len);

   169

	}

   170

   171

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

   172

	 * to start reading in more data */

   173

	_sl.bufp = _sl.buf;

   174

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

   175

}

   176

   177

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

   178

 * flush it to its final destination

   179

 * @return return the read byte from file

   180

 */

   181

static inline byte SlReadByteInternal()

   182

{

   183

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

   184

	return *_sl.bufp++;

   185

}

   186

   187

/** Wrapper for SlReadByteInternal */

   188

byte SlReadByte() {return SlReadByteInternal();}

   189

   190

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

   191

 * flush it to its destination (file)

   192

 * @param b the byte that is currently written

   193

 */

   194

static inline void SlWriteByteInternal(byte b)

   195

{

   196

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

   197

	*_sl.bufp++ = b;

   198

}

   199

   200

/** Wrapper for SlWriteByteInternal */

   201

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

   202

   203

static inline int SlReadUint16()

   204

{

   205

	int x = SlReadByte() << 8;

   206

	return x | SlReadByte();

   207

}

   208

   209

static inline uint32 SlReadUint32()

   210

{

   211

	uint32 x = SlReadUint16() << 16;

   212

	return x | SlReadUint16();

   213

}

   214

   215

static inline uint64 SlReadUint64()

   216

{

   217

	uint32 x = SlReadUint32();

   218

	uint32 y = SlReadUint32();

   219

	return (uint64)x << 32 | y;

   220

}

   221

   222

static inline void SlWriteUint16(uint16 v)

   223

{

   224

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

   225

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

   226

}

   227

   228

static inline void SlWriteUint32(uint32 v)

   229

{

   230

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

   231

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

   232

}

   233

   234

static inline void SlWriteUint64(uint64 x)

   235

{

   236

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

   237

	SlWriteUint32((uint32)x);

   238

}

   239

   240

/**

   241

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

   242

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

   243

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

   244

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

   245

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

   246

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

   247

 * @return Return the value of the index

   248

 */

   249

static uint SlReadSimpleGamma()

   250

{

   251

	uint i = SlReadByte();

   252

	if (HasBit(i, 7)) {

   253

		i &= ~0x80;

   254

		if (HasBit(i, 6)) {

   255

			i &= ~0x40;

   256

			if (HasBit(i, 5)) {

   257

				i &= ~0x20;

   258

				if (HasBit(i, 4))

   259

					SlError(STR_GAME_SAVELOAD_ERROR_BROKEN_SAVEGAME, "Unsupported gamma");

   260

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

   261

			}

   262

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

   263

		}

   264

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

   265

	}

   266

	return i;

   267

}

   268

   269

/**

   270

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

   271

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

   272

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

   273

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

   274

 * 0xxxxxxx

   275

 * 10xxxxxx xxxxxxxx

   276

 * 110xxxxx xxxxxxxx xxxxxxxx

   277

 * 1110xxxx xxxxxxxx xxxxxxxx xxxxxxxx

   278

 * @param i Index being written

   279

 */

   280

   281

static void SlWriteSimpleGamma(uint i)

   282

{

   283

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

   284

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

   285

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

   286

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

   287

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

   288

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

   289

			} else {

   290

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

   291

			}

   292

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

   293

		} else {

   294

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

   295

		}

   296

	}

   297

	SlWriteByte(i);

   298

}

   299

   300

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

   301

static inline uint SlGetGammaLength(uint i)

   302

{

   303

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

   304

}

   305

   306

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

   307

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

   308

   309

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

   310

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

   311

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

   312

   313

void SlSetArrayIndex(uint index)

   314

{

   315

	_sl.need_length = NL_WANTLENGTH;

   316

	_sl.array_index = index;

   317

}

   318

   319

static uint32 _next_offs;

   320

   321

/**

   322

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

   323

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

   324

 */

   325

int SlIterateArray()

   326

{

   327

	int index;

   328

   329

	/* After reading in the whole array inside the loop

   330

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

   331

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

   332

   333

	while (true) {

   334

		uint length = SlReadArrayLength();

   335

		if (length == 0) {

   336

			_next_offs = 0;

   337

			return -1;

   338

		}

   339

   340

		_sl.obj_len = --length;

   341

		_next_offs = SlGetOffs() + length;

   342

   343

		switch (_sl.block_mode) {

   344

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

   345

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

   346

		default:

   347

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

   348

			return -1; // error

   349

		}

   350

   351

		if (length != 0) return index;

   352

	}

   353

}

   354

   355

/**

   356

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

   357

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

   358

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

   359

 */

   360

void SlSetLength(size_t length)

   361

{

   362

	assert(_sl.save);

   363

   364

	switch (_sl.need_length) {

   365

	case NL_WANTLENGTH:

   366

		_sl.need_length = NL_NONE;

   367

		switch (_sl.block_mode) {

   368

		case CH_RIFF:

   369

			/* Ugly encoding of >16M RIFF chunks

   370

			 * The lower 24 bits are normal

   371

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

   372

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

   373

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

   374

			break;

   375

		case CH_ARRAY:

   376

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

   377

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

   378

				SlWriteArrayLength(1);

   379

			SlWriteArrayLength(length + 1);

   380

			break;

   381

		case CH_SPARSE_ARRAY:

   382

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

   383

			SlWriteSparseIndex(_sl.array_index);

   384

			break;

   385

		default: NOT_REACHED();

   386

		} break;

   387

	case NL_CALCLENGTH:

   388

		_sl.obj_len += length;

   389

		break;

   390

	}

   391

}

   392

   393

/**

   394

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

   395

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

   396

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

   397

 * @param length number of bytes this fast CopyBytes lasts

   398

 */

   399

static void SlCopyBytes(void *ptr, size_t length)

   400

{

   401

	byte *p = (byte*)ptr;

   402

   403

	if (_sl.save) {

   404

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

   405

	} else {

   406

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

   407

	}

   408

}

   409

   410

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

   411

 * anything with them, discarding them in effect

   412

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

   413

 */

   414

static inline void SlSkipBytes(size_t length)

   415

{

   416

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

   417

}

   418

   419

/* Get the length of the current object */

   420

uint SlGetFieldLength() {return _sl.obj_len;}

   421

   422

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

   423

 * @param ptr pointer to the variable

   424

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

   425

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

   426

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

   427

int64 ReadValue(const void *ptr, VarType conv)

   428

{

   429

	switch (GetVarMemType(conv)) {

   430

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

   431

	case SLE_VAR_I8:  return *(int8*  )ptr;

   432

	case SLE_VAR_U8:  return *(byte*  )ptr;

   433

	case SLE_VAR_I16: return *(int16* )ptr;

   434

	case SLE_VAR_U16: return *(uint16*)ptr;

   435

	case SLE_VAR_I32: return *(int32* )ptr;

   436

	case SLE_VAR_U32: return *(uint32*)ptr;

   437

	case SLE_VAR_I64: return *(int64* )ptr;

   438

	case SLE_VAR_U64: return *(uint64*)ptr;

   439

	case SLE_VAR_NULL:return 0;

   440

	default: NOT_REACHED();

   441

	}

   442

   443

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

   444

	return 0;

   445

}

   446

   447

/** Write the value of a setting

   448

 * @param ptr pointer to the variable

   449

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

   450

 *             with other flags. It is parsed upon read

   451

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

   452

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

   453

{

   454

	switch (GetVarMemType(conv)) {

   455

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

   456

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

   457

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

   458

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

   459

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

   460

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

   461

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

   462

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

   463

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

   464

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

   465

	case SLE_VAR_NULL: break;

   466

	default: NOT_REACHED();

   467

	}

   468

}

   469

   470

/**

   471

 * Handle all conversion and typechecking of variables here.

   472

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

   473

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

   474

 * goes exactly the opposite way

   475

 * @param ptr The object being filled/read

   476

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

   477

 */

   478

static void SlSaveLoadConv(void *ptr, VarType conv)

   479

{

   480

	int64 x = 0;

   481

   482

	if (_sl.save) { // SAVE values

   483

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

   484

		x = ReadValue(ptr, conv);

   485

   486

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

   487

		switch (GetVarFileType(conv)) {

   488

		case SLE_FILE_I8: assert(x >= -128 && x <= 127);     SlWriteByte(x);break;

   489

		case SLE_FILE_U8: assert(x >= 0 && x <= 255);        SlWriteByte(x);break;

   490

		case SLE_FILE_I16:assert(x >= -32768 && x <= 32767); SlWriteUint16(x);break;