1

/* $Id$ */

     2

     3

/** @file

     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

 * @see ChunkHandler

    16

 * @see SaveLoad

    17

 */

    18

#include "stdafx.h"

    19

#include "openttd.h"

    20

#include "debug.h"

    21

#include "functions.h"

    22

#include "vehicle.h"

    23

#include "station.h"

    24

#include "thread.h"

    25

#include "town.h"

    26

#include "player.h"

    27

#include "saveload.h"

    28

#include "network.h"

    29

#include "variables.h"

    30

#include <setjmp.h>

    31

    32

const uint16 SAVEGAME_VERSION = 23;

    33

uint16 _sl_version;       /// the major savegame version identifier

    34

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

    35

    36

typedef void WriterProc(uint len);

    37

typedef uint ReaderProc(void);

    38

    39

typedef uint ReferenceToIntProc(const void *obj, SLRefType rt);

    40

typedef void *IntToReferenceProc(uint index, SLRefType rt);

    41

    42

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

    43

static struct {

    44

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

    45

	byte need_length;                    /// ???

    46

	byte block_mode;                     /// ???

    47

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

    48

    49

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

    50

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

    51

    52

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

    53

    54

	WriterProc *write_bytes;             /// savegame writer function

    55

	ReaderProc *read_bytes;              /// savegame loader function

    56

    57

	ReferenceToIntProc *ref_to_int_proc; /// function to convert pointers to numbers when saving a game

    58

	IntToReferenceProc *int_to_ref_proc; /// function to convert numbers to pointers when loading a game

    59

    60

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

    61

	const SaveLoad* const *includes;     /// the internal layouf of the given chunk

    62

    63

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

    64

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

    65

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

    66

    67

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

    68

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

    69

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

    70

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

    71

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

    72

    73

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

    74

	const char *excpt_msg;               /// the error message

    75

	jmp_buf excpt;                       /// @todo used to jump to "exception handler";  really ugly

    76

} _sl;

    77

    78

    79

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

    80

    81

/**

    82

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

    83

 */

    84

static void SlReadFill(void)

    85

{

    86

	uint len = _sl.read_bytes();

    87

	assert(len != 0);

    88

    89

	_sl.bufp = _sl.buf;

    90

	_sl.bufe = _sl.buf + len;

    91

	_sl.offs_base += len;

    92

}

    93

    94

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

    95

    96

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

    97

 * as it appears in memory. @see VarTypes

    98

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

    99

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

   100

static inline byte SlCalcConvMemLen(VarType conv)

   101

{

   102

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

   103

	byte length = (conv >> 4) & 0xF;

   104

	assert(length < lengthof(conv_mem_size));

   105

	return conv_mem_size[length];

   106

}

   107

   108

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

   109

 * as it appears in a saved game. @see VarTypes

   110

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

   111

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

   112

static inline byte SlCalcConvFileLen(VarType conv)

   113

{

   114

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

   115

	byte length = conv & 0xF;

   116

	assert(length < lengthof(conv_file_size));

   117

	return conv_file_size[length];

   118

}

   119

   120

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

   121

static inline size_t SlCalcRefLen(void) {return 2;}

   122

   123

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

   124

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

   125

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

   126

 */

   127

static void SlWriteFill(void)

   128

{

   129

	// flush the buffer to disk (the writer)

   130

	if (_sl.bufp != NULL) {

   131

		uint len = _sl.bufp - _sl.buf;

   132

		_sl.offs_base += len;

   133

		if (len) _sl.write_bytes(len);

   134

	}

   135

   136

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

   137

	* to start reading in more data */

   138

	_sl.bufp = _sl.buf;

   139

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

   140

}

   141

   142

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

   143

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

   144

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

   145

static void NORETURN SlError(const char *msg)

   146

{

   147

	_sl.excpt_msg = msg;

   148

	longjmp(_sl.excpt, 0);

   149

}

   150

   151

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

   152

 * flush it to its final destination

   153

 * @return return the read byte from file

   154

 */

   155

static inline byte SlReadByteInternal(void)

   156

{

   157

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

   158

	return *_sl.bufp++;

   159

}

   160

   161

/** Wrapper for SlReadByteInternal */

   162

byte SlReadByte(void) {return SlReadByteInternal();}

   163

   164

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

   165

 * flush it to its destination (file)

   166

 * @param b the byte that is currently written

   167

 */

   168

static inline void SlWriteByteInternal(byte b)

   169

{

   170

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

   171

	*_sl.bufp++ = b;

   172

}

   173

   174

/** Wrapper for SlWriteByteInternal */

   175

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

   176

   177

static inline int SlReadUint16(void)

   178

{

   179

	int x = SlReadByte() << 8;

   180

	return x | SlReadByte();

   181

}

   182

   183

static inline uint32 SlReadUint32(void)

   184

{

   185

	uint32 x = SlReadUint16() << 16;

   186

	return x | SlReadUint16();

   187

}

   188

   189

static inline uint64 SlReadUint64(void)

   190

{

   191

	uint32 x = SlReadUint32();

   192

	uint32 y = SlReadUint32();

   193

	return (uint64)x << 32 | y;

   194

}

   195

   196

static inline void SlWriteUint16(uint16 v)

   197

{

   198

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

   199

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

   200

}

   201

   202

static inline void SlWriteUint32(uint32 v)

   203

{

   204

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

   205

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

   206

}

   207

   208

static inline void SlWriteUint64(uint64 x)

   209

{

   210

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

   211

	SlWriteUint32((uint32)x);

   212

}

   213

   214

/**

   215

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

   216

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

   217

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

   218

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

   219

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

   220

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

   221

 * @return Return the value of the index

   222

 */

   223

static uint SlReadSimpleGamma(void)

   224

{

   225

	uint i = SlReadByte();

   226

	if (HASBIT(i, 7)) {

   227

		i &= ~0x80;

   228

		if (HASBIT(i, 6)) {

   229

			i &= ~0x40;

   230

			if (HASBIT(i, 5)) {

   231

				i &= ~0x20;

   232

				if (HASBIT(i, 4))

   233

					SlError("Unsupported gamma");

   234

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

   235

			}

   236

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

   237

		}

   238

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

   239

	}

   240

	return i;

   241

}

   242

   243

/**

   244

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

   245

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

   246

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

   247

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

   248

 * 0xxxxxxx

   249

 * 10xxxxxx xxxxxxxx

   250

 * 110xxxxx xxxxxxxx xxxxxxxx

   251

 * 1110xxxx xxxxxxxx xxxxxxxx xxxxxxxx

   252

 * @param i Index being written

   253

 */

   254

   255

static void SlWriteSimpleGamma(uint i)

   256

{

   257

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

   258

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

   259

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

   260

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

   261

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

   262

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

   263

			} else {

   264

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

   265

			}

   266

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

   267

		} else {

   268

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

   269

		}

   270

	}

   271

	SlWriteByte(i);

   272

}

   273

   274

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

   275

static inline uint SlGetGammaLength(uint i) {

   276

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

   277

}

   278

   279

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

   280

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

   281

   282

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

   283

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

   284

   285

void SlSetArrayIndex(uint index)

   286

{

   287

	_sl.need_length = NL_WANTLENGTH;

   288

	_sl.array_index = index;

   289

}

   290

   291

/**

   292

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

   293

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

   294

 */

   295

int SlIterateArray(void)

   296

{

   297

	int index;

   298

	static uint32 next_offs;

   299

   300

	/* After reading in the whole array inside the loop

   301

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

   302

	assert(next_offs == 0 || SlGetOffs() == next_offs);

   303

   304

	while (true) {

   305

		uint length = SlReadArrayLength();

   306

		if (length == 0) {

   307

			next_offs = 0;

   308

			return -1;

   309

		}

   310

   311

		_sl.obj_len = --length;

   312

		next_offs = SlGetOffs() + length;

   313

   314

		switch (_sl.block_mode) {

   315

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

   316

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

   317

		default:

   318

			DEBUG(misc, 0) ("[Sl] SlIterateArray: error");

   319

			return -1; // error

   320

		}

   321

   322

		if (length != 0) return index;

   323

	}

   324

}

   325

   326

/**

   327

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

   328

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

   329

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

   330

 */

   331

void SlSetLength(size_t length)

   332

{

   333

	assert(_sl.save);

   334

   335

	switch (_sl.need_length) {

   336

	case NL_WANTLENGTH:

   337

		_sl.need_length = NL_NONE;

   338

		switch (_sl.block_mode) {

   339

		case CH_RIFF:

   340

			// Ugly encoding of >16M RIFF chunks

   341

			// The lower 24 bits are normal

   342

			// The uppermost 4 bits are bits 24:27

   343

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

   344

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

   345

			break;

   346

		case CH_ARRAY:

   347

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

   348

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

   349

				SlWriteArrayLength(1);

   350

			SlWriteArrayLength(length + 1);

   351

			break;

   352

		case CH_SPARSE_ARRAY:

   353

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

   354

			SlWriteSparseIndex(_sl.array_index);

   355

			break;

   356

		default: NOT_REACHED();

   357

		} break;

   358

	case NL_CALCLENGTH:

   359

		_sl.obj_len += length;

   360

		break;

   361

	}

   362

}

   363

   364

/**

   365

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

   366

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

   367

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

   368

 * @param length number of bytes this fast CopyBytes lasts

   369

 */

   370

static void SlCopyBytes(void *ptr, size_t length)

   371

{

   372

	byte *p = (byte*)ptr;

   373

   374

	if (_sl.save) {

   375

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

   376

	} else {

   377

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

   378

	}

   379

}

   380

   381

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

   382

 * anything with them, discarding them in effect

   383

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

   384

 */

   385

static inline void SlSkipBytes(size_t length)

   386

{

   387

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

   388

}

   389

   390

/* Get the length of the current object */

   391

uint SlGetFieldLength(void) {return _sl.obj_len;}

   392

   393

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

   394

 * @param ptr pointer to the variable

   395

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

   396

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

   397

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

   398

int64 ReadValue(const void *ptr, VarType conv)

   399

{

   400

	switch (GetVarMemType(conv)) {

   401

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

   402

	case SLE_VAR_I8:  return *(int8*  )ptr;

   403

	case SLE_VAR_U8:  return *(byte*  )ptr;

   404

	case SLE_VAR_I16: return *(int16* )ptr;

   405

	case SLE_VAR_U16: return *(uint16*)ptr;

   406

	case SLE_VAR_I32: return *(int32* )ptr;

   407

	case SLE_VAR_U32: return *(uint32*)ptr;

   408

	case SLE_VAR_I64: return *(int64* )ptr;

   409

	case SLE_VAR_U64: return *(uint64*)ptr;

   410

	case SLE_VAR_NULL:return 0;

   411

	default: NOT_REACHED();

   412

	}

   413

   414

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

   415

	return 0;

   416

}

   417

   418

/** Write the value of a setting

   419

 * @param ptr pointer to the variable

   420

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

   421

 * with other flags. It is parsed upon read

   422

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

   423

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

   424

{

   425

	switch (GetVarMemType(conv)) {

   426

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

   427

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

   428

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

   429

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

   430

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

   431

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

   432

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

   433

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

   434

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

   435

	case SLE_VAR_NULL: break;

   436

	default: NOT_REACHED();

   437

	}

   438

}

   439

   440

/**

   441

 * Handle all conversion and typechecking of variables here.

   442

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

   443

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

   444

 * goes exactly the opposite way

   445

 * @param ptr The object being filled/read

   446

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

   447

 */

   448

static void SlSaveLoadConv(void *ptr, VarType conv)

   449

{

   450

	int64 x = 0;

   451

   452

	if (_sl.save) { /* SAVE values */

   453

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

   454

		x = ReadValue(ptr, conv);

   455

   456

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

   457

		switch (GetVarFileType(conv)) {

   458

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

   459

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

   460

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

   461

		case SLE_FILE_STRINGID:

   462

		case SLE_FILE_U16:assert(x >= 0 && x <= 65535);      SlWriteUint16(x);break;

   463

		case SLE_FILE_I32:

   464

		case SLE_FILE_U32:                                   SlWriteUint32((uint32)x);break;

   465

		case SLE_FILE_I64:

   466

		case SLE_FILE_U64:                                   SlWriteUint64(x);break;

   467

		default: NOT_REACHED();

   468

		}

   469

	} else { /* LOAD values */

   470

   471

		/* Read a value from the file */

   472

		switch (GetVarFileType(conv)) {

   473

		case SLE_FILE_I8:  x = (int8  )SlReadByte();   break;

   474

		case SLE_FILE_U8:  x = (byte  )SlReadByte();   break;

   475

		case SLE_FILE_I16: x = (int16 )SlReadUint16(); break;

   476

		case SLE_FILE_U16: x = (uint16)SlReadUint16(); break;

   477

		case SLE_FILE_I32: x = (int32 )SlReadUint32(); break;

   478

		case SLE_FILE_U32: x = (uint32)SlReadUint32(); break;

   479

		case SLE_FILE_I64: x = (int64 )SlReadUint64(); break;

   480

		case SLE_FILE_U64: x = (uint64)SlReadUint64(); break;

   481

		case SLE_FILE_STRINGID: x = RemapOldStringID((uint16)SlReadUint16()); break;

   482

		default: NOT_REACHED();

   483

		}

   484

   485

		/* Write The value to the struct. These ARE endian safe. */

   486

		WriteValue(ptr, conv, x);

   487

	}

   488

}

   489

   490

static inline size_t SlCalcStringLen(const char *ptr, uint length)

   491

{

   492

	DEBUG(misc, 1) ("[Sl] TODO: save/load real length");

   493

	return length;//(_sl.save) ? min(strlen(ptr), length - 1) : SlReadArrayLength();

   494

}

   495