/* $Id$ */ /** @file * All actions handling saving and loading goes on in this file. The general actions * are as follows for saving a game (loading is analogous): * <ol> * <li>initialize the writer by creating a temporary memory-buffer for it * <li>go through all to-be saved elements, each 'chunk' (ChunkHandler) prefixed by a label * <li>use their description array (SaveLoad) to know what elements to save and in what version * of the game it was active (used when loading) * <li>write all data byte-by-byte to the temporary buffer so it is endian-safe * <li>when the buffer is full; flush it to the output (eg save to file) (_sl.buf, _sl.bufp, _sl.bufe) * <li>repeat this until everything is done, and flush any remaining output to file * </ol> * @see ChunkHandler * @see SaveLoad */ #include "stdafx.h" #include "openttd.h" #include "debug.h" #include "functions.h" #include "hal.h" #include "vehicle.h" #include "station.h" #include "thread.h" #include "town.h" #include "player.h" #include "saveload.h" #include "network.h" #include "variables.h" #include <setjmp.h> const uint16 SAVEGAME_VERSION = 24; uint16 _sl_version; /// the major savegame version identifier byte _sl_minor_version; /// the minor savegame version, DO NOT USE! typedef void WriterProc(uint len); typedef uint ReaderProc(void); typedef uint ReferenceToIntProc(const void *obj, SLRefType rt); typedef void *IntToReferenceProc(uint index, SLRefType rt); /** The saveload struct, containing reader-writer functions, bufffer, version, etc. */ static struct { bool save; /// are we doing a save or a load atm. True when saving byte need_length; /// ??? byte block_mode; /// ??? bool error; /// did an error occur or not int obj_len; /// the length of the current object we are busy with int array_index, last_array_index; /// in the case of an array, the current and last positions uint32 offs_base; /// the offset in number of bytes since we started writing data (eg uncompressed savegame size) WriterProc *write_bytes; /// savegame writer function ReaderProc *read_bytes; /// savegame loader function ReferenceToIntProc *ref_to_int_proc; /// function to convert pointers to numbers when saving a game IntToReferenceProc *int_to_ref_proc; /// function to convert numbers to pointers when loading a game const ChunkHandler* const *chs; /// the chunk of data that is being processed atm (vehicles, signs, etc.) const SaveLoad* const *includes; /// the internal layouf of the given chunk /** When saving/loading savegames, they are always saved to a temporary memory-place * to be flushed to file (save) or to final place (load) when full. */ byte *bufp, *bufe; /// bufp(ointer) gives the current position in the buffer bufe(nd) gives the end of the buffer // these 3 may be used by compressor/decompressors. byte *buf; /// pointer to temporary memory to read/write, initialized by SaveLoadFormat->initread/write byte *buf_ori; /// pointer to the original memory location of buf, used to free it afterwards uint bufsize; /// the size of the temporary memory *buf FILE *fh; /// the file from which is read or written to void (*excpt_uninit)(void); /// the function to execute on any encountered error const char *excpt_msg; /// the error message jmp_buf excpt; /// @todo used to jump to "exception handler"; really ugly } _sl; enum NeedLengthValues {NL_NONE = 0, NL_WANTLENGTH = 1, NL_CALCLENGTH = 2}; /** * Fill the input buffer by reading from the file with the given reader */ static void SlReadFill(void) { uint len = _sl.read_bytes(); assert(len != 0); _sl.bufp = _sl.buf; _sl.bufe = _sl.buf + len; _sl.offs_base += len; } static inline uint32 SlGetOffs(void) {return _sl.offs_base - (_sl.bufe - _sl.bufp);} /** Return the size in bytes of a certain type of normal/atomic variable * as it appears in memory. @see VarTypes * @param conv @VarType type of variable that is used for calculating the size * @return Return the size of this type in bytes */ static inline byte SlCalcConvMemLen(VarType conv) { static const byte conv_mem_size[] = {1, 1, 1, 2, 2, 4, 4, 8, 8, 0}; byte length = (conv >> 4) & 0xF; assert(length < lengthof(conv_mem_size)); return conv_mem_size[length]; } /** Return the size in bytes of a certain type of normal/atomic variable * as it appears in a saved game. @see VarTypes * @param conv @VarType type of variable that is used for calculating the size * @return Return the size of this type in bytes */ static inline byte SlCalcConvFileLen(VarType conv) { static const byte conv_file_size[] = {1, 1, 2, 2, 4, 4, 8, 8, 2}; byte length = conv & 0xF; assert(length < lengthof(conv_file_size)); return conv_file_size[length]; } /* Return the size in bytes of a reference (pointer) */ static inline size_t SlCalcRefLen(void) {return 2;} /** Flush the output buffer by writing to disk with the given reader. * If the buffer pointer has not yet been set up, set it up now. Usually * only called when the buffer is full, or there is no more data to be processed */ static void SlWriteFill(void) { // flush the buffer to disk (the writer) if (_sl.bufp != NULL) { uint len = _sl.bufp - _sl.buf; _sl.offs_base += len; if (len) _sl.write_bytes(len); } /* All the data from the buffer has been written away, rewind to the beginning * to start reading in more data */ _sl.bufp = _sl.buf; _sl.bufe = _sl.buf + _sl.bufsize; } /** Error handler, calls longjmp to simulate an exception. * @todo this was used to have a central place to handle errors, but it is * pretty ugly, and seriously interferes with any multithreaded approaches */ static void NORETURN SlError(const char *msg) { _sl.excpt_msg = msg; longjmp(_sl.excpt, 0); } /** Read in a single byte from file. If the temporary buffer is full, * flush it to its final destination * @return return the read byte from file */ static inline byte SlReadByteInternal(void) { if (_sl.bufp == _sl.bufe) SlReadFill(); return *_sl.bufp++; } /** Wrapper for SlReadByteInternal */ byte SlReadByte(void) {return SlReadByteInternal();} /** Write away a single byte from memory. If the temporary buffer is full, * flush it to its destination (file) * @param b the byte that is currently written */ static inline void SlWriteByteInternal(byte b) { if (_sl.bufp == _sl.bufe) SlWriteFill(); *_sl.bufp++ = b; } /** Wrapper for SlWriteByteInternal */ void SlWriteByte(byte b) {SlWriteByteInternal(b);} static inline int SlReadUint16(void) { int x = SlReadByte() << 8; return x | SlReadByte(); } static inline uint32 SlReadUint32(void) { uint32 x = SlReadUint16() << 16; return x | SlReadUint16(); } static inline uint64 SlReadUint64(void) { uint32 x = SlReadUint32(); uint32 y = SlReadUint32(); return (uint64)x << 32 | y; } static inline void SlWriteUint16(uint16 v) { SlWriteByte(GB(v, 8, 8)); SlWriteByte(GB(v, 0, 8)); } static inline void SlWriteUint32(uint32 v) { SlWriteUint16(GB(v, 16, 16)); SlWriteUint16(GB(v, 0, 16)); } static inline void SlWriteUint64(uint64 x) { SlWriteUint32((uint32)(x >> 32)); SlWriteUint32((uint32)x); } /** * Read in the header descriptor of an object or an array. * If the highest bit is set (7), then the index is bigger than 127 * elements, so use the next byte to read in the real value. * The actual value is then both bytes added with the first shifted * 8 bits to the left, and dropping the highest bit (which only indicated a big index). * x = ((x & 0x7F) << 8) + SlReadByte(); * @return Return the value of the index */ static uint SlReadSimpleGamma(void) { uint i = SlReadByte(); if (HASBIT(i, 7)) { i &= ~0x80; if (HASBIT(i, 6)) { i &= ~0x40; if (HASBIT(i, 5)) { i &= ~0x20; if (HASBIT(i, 4)) SlError("Unsupported gamma"); i = (i << 8) | SlReadByte(); } i = (i << 8) | SlReadByte(); } i = (i << 8) | SlReadByte(); } return i; } /** * Write the header descriptor of an object or an array. * If the element is bigger than 127, use 2 bytes for saving * and use the highest byte of the first written one as a notice * that the length consists of 2 bytes, etc.. like this: * 0xxxxxxx * 10xxxxxx xxxxxxxx * 110xxxxx xxxxxxxx xxxxxxxx * 1110xxxx xxxxxxxx xxxxxxxx xxxxxxxx * @param i Index being written */ static void SlWriteSimpleGamma(uint i) { if (i >= (1 << 7)) { if (i >= (1 << 14)) { if (i >= (1 << 21)) { assert(i < (1 << 28)); SlWriteByte((byte)0xE0 | (i>>24)); SlWriteByte((byte)(i>>16)); } else { SlWriteByte((byte)0xC0 | (i>>16)); } SlWriteByte((byte)(i>>8)); } else { SlWriteByte((byte)(0x80 | (i>>8))); } } SlWriteByte(i); } /** Return how many bytes used to encode a gamma value */ static inline uint SlGetGammaLength(uint i) { return 1 + (i >= (1 << 7)) + (i >= (1 << 14)) + (i >= (1 << 21)); } static inline uint SlReadSparseIndex(void) {return SlReadSimpleGamma();} static inline void SlWriteSparseIndex(uint index) {SlWriteSimpleGamma(index);} static inline uint SlReadArrayLength(void) {return SlReadSimpleGamma();} static inline void SlWriteArrayLength(uint length) {SlWriteSimpleGamma(length);} void SlSetArrayIndex(uint index) { _sl.need_length = NL_WANTLENGTH; _sl.array_index = index; } /** * Iterate through the elements of an array and read the whole thing * @return The index of the object, or -1 if we have reached the end of current block */ int SlIterateArray(void) { int index; static uint32 next_offs; /* After reading in the whole array inside the loop * we must have read in all the data, so we must be at end of current block. */ assert(next_offs == 0 || SlGetOffs() == next_offs); while (true) { uint length = SlReadArrayLength(); if (length == 0) { next_offs = 0; return -1; } _sl.obj_len = --length; next_offs = SlGetOffs() + length; switch (_sl.block_mode) { case CH_SPARSE_ARRAY: index = (int)SlReadSparseIndex(); break; case CH_ARRAY: index = _sl.array_index++; break; default: DEBUG(misc, 0) ("[Sl] SlIterateArray: error"); return -1; // error } if (length != 0) return index; } } /** * Sets the length of either a RIFF object or the number of items in an array. * This lets us load an object or an array of arbitrary size * @param length The length of the sought object/array */ void SlSetLength(size_t length) { assert(_sl.save); switch (_sl.need_length) { case NL_WANTLENGTH: _sl.need_length = NL_NONE; switch (_sl.block_mode) { case CH_RIFF: // Ugly encoding of >16M RIFF chunks // The lower 24 bits are normal // The uppermost 4 bits are bits 24:27 assert(length < (1<<28)); SlWriteUint32((length & 0xFFFFFF) | ((length >> 24) << 28)); break; case CH_ARRAY: assert(_sl.last_array_index <= _sl.array_index); while (++_sl.last_array_index <= _sl.array_index) SlWriteArrayLength(1); SlWriteArrayLength(length + 1); break; case CH_SPARSE_ARRAY: SlWriteArrayLength(length + 1 + SlGetGammaLength(_sl.array_index)); // Also include length of sparse index. SlWriteSparseIndex(_sl.array_index); break; default: NOT_REACHED(); } break; case NL_CALCLENGTH: _sl.obj_len += length; break; } } /** * Save/Load bytes. These do not need to be converted to Little/Big Endian * so directly write them or read them to/from file * @param ptr The source or destination of the object being manipulated * @param length number of bytes this fast CopyBytes lasts */ static void SlCopyBytes(void *ptr, size_t length) { byte *p = (byte*)ptr; if (_sl.save) { for (; length != 0; length--) {SlWriteByteInternal(*p++);} } else { for (; length != 0; length--) {*p++ = SlReadByteInternal();} } } /** 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(); } /* Get the length of the current object */ uint SlGetFieldLength(void) {return _sl.obj_len;} /** Return a signed-long version of the value of a setting * @param ptr pointer to the variable * @param conv type of variable, can be a non-clean * type, eg one with other flags because it is parsed * @return returns the value of the pointer-setting */ int64 ReadValue(const void *ptr, VarType conv) { switch (GetVarMemType(conv)) { case SLE_VAR_BL: return (*(bool*)ptr != 0); case SLE_VAR_I8: return *(int8* )ptr; case SLE_VAR_U8: return *(byte* )ptr; case SLE_VAR_I16: return *(int16* )ptr; case SLE_VAR_U16: return *(uint16*)ptr; case SLE_VAR_I32: return *(int32* )ptr; case SLE_VAR_U32: return *(uint32*)ptr; case SLE_VAR_I64: return *(int64* )ptr; case SLE_VAR_U64: return *(uint64*)ptr; case SLE_VAR_NULL:return 0; default: NOT_REACHED(); } /* useless, but avoids compiler warning this way */ return 0; } /** Write the value of a setting * @param ptr pointer to the variable * @param conv type of variable, can be a non-clean type, eg * with other flags. It is parsed upon read * @param var the new value being given to the variable */ void WriteValue(void *ptr, VarType conv, int64 val) { switch (GetVarMemType(conv)) { case SLE_VAR_BL: *(bool *)ptr = (val != 0); break; case SLE_VAR_I8: *(int8 *)ptr = val; break; case SLE_VAR_U8: *(byte *)ptr = val; break; case SLE_VAR_I16: *(int16 *)ptr = val; break; case SLE_VAR_U16: *(uint16*)ptr = val; break; case SLE_VAR_I32: *(int32 *)ptr = val; break; case SLE_VAR_U32: *(uint32*)ptr = val; break; case SLE_VAR_I64: *(int64 *)ptr = val; break; case SLE_VAR_U64: *(uint64*)ptr = val; break; case SLE_VAR_NULL: break; default: NOT_REACHED(); } } /** * Handle all conversion and typechecking of variables here. * In the case of saving, read in the actual value from the struct * and then write them to file, endian safely. Loading a value * goes exactly the opposite way * @param ptr The object being filled/read * @param conv @VarType type of the current element of the struct */ static void SlSaveLoadConv(void *ptr, VarType conv) { int64 x = 0; if (_sl.save) { /* SAVE values */ /* Read a value from the struct. These ARE endian safe. */ x = ReadValue(ptr, conv); /* Write the value to the file and check if its value is in the desired range */ switch (GetVarFileType(conv)) { case SLE_FILE_I8: assert(x >= -128 && x <= 127); SlWriteByte(x);break; case SLE_FILE_U8: assert(x >= 0 && x <= 255); SlWriteByte(x);break; case SLE_FILE_I16:assert(x >= -32768 && x <= 32767); SlWriteUint16(x);break; case SLE_FILE_STRINGID: case SLE_FILE_U16:assert(x >= 0 && x <= 65535); SlWriteUint16(x);break; case SLE_FILE_I32: case SLE_FILE_U32: SlWriteUint32((uint32)x);break; case SLE_FILE_I64: case SLE_FILE_U64: SlWriteUint64(x);break; default: NOT_REACHED(); } } else { /* LOAD values */ /* Read a value from the file */ switch (GetVarFileType(conv)) { case SLE_FILE_I8: x = (int8 )SlReadByte(); break; case SLE_FILE_U8: x = (byte )SlReadByte(); break; case SLE_FILE_I16: x = (int16 )SlReadUint16(); break; case SLE_FILE_U16: x = (uint16)SlReadUint16(); break; case SLE_FILE_I32: x = (int32 )SlReadUint32(); break; case SLE_FILE_U32: x = (uint32)SlReadUint32(); break; case SLE_FILE_I64: x = (int64 )SlReadUint64(); break; case SLE_FILE_U64: x = (uint64)SlReadUint64(); break; case SLE_FILE_STRINGID: x = RemapOldStringID((uint16)SlReadUint16()); break; default: NOT_REACHED(); } /* Write The value to the struct. These ARE endian safe. */ WriteValue(ptr, conv, x); } } static inline size_t SlCalcStringLen(const char *ptr, uint length) { DEBUG(misc, 1) ("[Sl] TODO: save/load real length"); return length;//(_sl.save) ? min(strlen(ptr), length - 1) : SlReadArrayLength(); } /** * Save/Load a string. * @param ptr the string being manipulated * @param the length of the string (full length) * @param conv must be SLE_FILE_STRING * @todo the full length of the string is saved, even when the buffer * is 512 bytes and only 10 of those are used */ static void SlString(void *ptr, uint length, VarType conv) { uint len = SlCalcStringLen(ptr, length); assert((conv & 0xF) == SLE_FILE_STRING); SlCopyBytes(ptr, len); } /** * Return the size in bytes of a certain type of atomic array * @param length The length of the array counted in elements * @param conv @VarType type of the variable that is used in calculating the size */ static inline size_t SlCalcArrayLen(uint length, VarType conv) { return SlCalcConvFileLen(conv) * length; } /** * Save/Load an array. * @param array The array being manipulated * @param length The length of the array in elements * @param conv @VarType type of the atomic array (int, byte, uint64, etc.) */ void SlArray(void *array, uint length, VarType conv) { // Automatically calculate the length? if (_sl.need_length != NL_NONE) { SlSetLength(SlCalcArrayLen(length, conv)); // Determine length only? if (_sl.need_length == NL_CALCLENGTH) return; } /* NOTICE - handle some buggy stuff, in really old versions everything was saved * as a byte-type. So detect this, and adjust array size accordingly */ if (!_sl.save && _sl_version == 0) { if (conv == SLE_INT16 || conv == SLE_UINT16 || conv == SLE_STRINGID || conv == SLE_INT32 || conv == SLE_UINT32) { length *= SlCalcConvFileLen(conv); conv = SLE_INT8; } } /* If the size of elements is 1 byte both in file and memory, no special * conversion is needed, use specialized copy-copy function to speed up things */ if (conv == SLE_INT8 || conv == SLE_UINT8) { SlCopyBytes(array, length); } else { byte *a = (byte*)array; byte mem_size = SlCalcConvMemLen(conv); for (; length != 0; length --) { SlSaveLoadConv(a, conv); a += mem_size; // get size } } } /* Are we going to save this object or not? */ static inline bool SlIsObjectValidInSavegame(const SaveLoad *sld) { if (_sl_version < sld->version_from || _sl_version > sld->version_to) return false; if (sld->conv & SLF_SAVE_NO) return false; return true; } /** Are we going to load this variable when loading a savegame or not? * @note If the variable is skipped it is skipped in the savegame * bytestream itself as well, so there is no need to skip it somewhere else */ static inline bool SlSkipVariableOnLoad(const SaveLoad *sld) { if ((sld->conv & SLF_NETWORK_NO) && !_sl.save && _networking && !_network_server) { SlSkipBytes(SlCalcConvMemLen(sld->conv) * sld->length); return true; } return false; } /** * Calculate the size of an object. * @param sld The @SaveLoad description of the object so we know how to manipulate it */ static size_t SlCalcObjLength(const SaveLoad *sld) { size_t length = 0; // Need to determine the length and write a length tag. for (; sld->cmd != SL_END; sld++) { length += SlCalcObjMemberLength(sld); } return length; } size_t SlCalcObjMemberLength(const SaveLoad *sld) { assert(_sl.save); switch (sld->cmd) { case SL_VAR: case SL_REF: case SL_ARR: case SL_STR: /* CONDITIONAL saveload types depend on the savegame version */ if (!SlIsObjectValidInSavegame(sld)) break; switch (sld->cmd) { case SL_VAR: return SlCalcConvFileLen(sld->conv); case SL_REF: return SlCalcRefLen(); case SL_ARR: return SlCalcArrayLen(sld->length, sld->conv); case SL_STR: return SlCalcStringLen(sld->address, sld->length); default: NOT_REACHED(); } break; case SL_WRITEBYTE: return 1; // a byte is logically of size 1 case SL_INCLUDE: return SlCalcObjLength(_sl.includes[sld->version_from]); default: NOT_REACHED(); } return 0; } bool SlObjectMember(void *ptr, const SaveLoad *sld) { VarType conv = GB(sld->conv, 0, 8); switch (sld->cmd) { case SL_VAR: case SL_REF: case SL_ARR: case SL_STR: /* CONDITIONAL saveload types depend on the savegame version */ if (!SlIsObjectValidInSavegame(sld)) return false; if (SlSkipVariableOnLoad(sld)) return false; switch (sld->cmd) { case SL_VAR: SlSaveLoadConv(ptr, conv); break; case SL_REF: /* Reference variable, translate */ /// @todo XXX - another artificial limitof 65K elements of pointers? if (_sl.save) { // XXX - read/write pointer as uint16? What is with higher indeces? SlWriteUint16(_sl.ref_to_int_proc(*(void**)ptr, conv)); } else *(void**)ptr = _sl.int_to_ref_proc(SlReadUint16(), conv); break; case SL_ARR: SlArray(ptr, sld->length, conv); break; case SL_STR: SlString(ptr, sld->length, conv); break; default: NOT_REACHED(); } break; /* SL_WRITEBYTE translates a value of a variable to another one upon * saving or loading. * XXX - variable renaming abuse * game_value: the value of the variable ingame is abused by sld->version_from * file_value: the value of the variable in the savegame is abused by sld->version_to */ case SL_WRITEBYTE: if (_sl.save) { SlWriteByte(sld->version_to); } else { *(byte*)ptr = sld->version_from; } break; /* SL_INCLUDE loads common code for a type * XXX - variable renaming abuse * include_index: common code to include from _desc_includes[], abused by sld->version_from */ case SL_INCLUDE: SlObject(ptr, _sl.includes[sld->version_from]); break; default: NOT_REACHED(); } return true; } /** * Main SaveLoad function. * @param object The object that is being saved or loaded * @param sld The @SaveLoad description of the object so we know how to manipulate it */ void SlObject(void *object, const SaveLoad *sld) { // Automatically calculate the length? if (_sl.need_length != NL_NONE) { SlSetLength(SlCalcObjLength(sld)); if (_sl.need_length == NL_CALCLENGTH) return; } for (; sld->cmd != SL_END; sld++) { void *ptr = (byte*)object + (unsigned long)sld->address; SlObjectMember(ptr, sld); } } /** * Save or Load (a list of) global variables * @param desc The global variable that is being loaded or saved */ void SlGlobList(const SaveLoadGlobVarList *sldg) { if (_sl.need_length != NL_NONE) { SlSetLength(SlCalcObjLength((const SaveLoad*)sldg)); if (_sl.need_length == NL_CALCLENGTH) return; } for (; sldg->cmd != SL_END; sldg++) { SlObjectMember(sldg->address, (const SaveLoad*)sldg); } } /** * Do something of which I have no idea what it is :P * @param proc The callback procedure that is called * @param arg The variable that will be used for the callback procedure */ void SlAutolength(AutolengthProc *proc, void *arg) { uint32 offs; assert(_sl.save); // Tell it to calculate the length _sl.need_length = NL_CALCLENGTH; _sl.obj_len = 0; proc(arg); // Setup length _sl.need_length = NL_WANTLENGTH; SlSetLength(_sl.obj_len); offs = SlGetOffs() + _sl.obj_len; // And write the stuff proc(arg); assert(offs == SlGetOffs()); } /** * Load a chunk of data (eg vehicles, stations, etc.) * @param ch The chunkhandler that will be used for the operation */ static void SlLoadChunk(const ChunkHandler *ch) { byte m = SlReadByte(); size_t len; uint32 endoffs; _sl.block_mode = m; _sl.obj_len = 0; switch (m) { case CH_ARRAY: _sl.array_index = 0; ch->load_proc(); break; case CH_SPARSE_ARRAY: ch->load_proc(); break; default: if ((m & 0xF) == CH_RIFF) { // Read length len = (SlReadByte() << 16) | ((m >> 4) << 24); len += SlReadUint16(); _sl.obj_len = len; endoffs = SlGetOffs() + len; ch->load_proc(); assert(SlGetOffs() == endoffs); } else { SlError("Invalid chunk type"); } break; } } /* Stub Chunk handlers to only calculate length and do nothing else */ static ChunkSaveLoadProc *_tmp_proc_1; static inline void SlStubSaveProc2(void *arg) {_tmp_proc_1();} static void SlStubSaveProc(void) {SlAutolength(SlStubSaveProc2, NULL);} /** Save a chunk of data (eg. vehicles, stations, etc.). Each chunk is * prefixed by an ID identifying it, followed by data, and terminator where appropiate * @param ch The chunkhandler that will be used for the operation */ static void SlSaveChunk(const ChunkHandler *ch) { ChunkSaveLoadProc *proc = ch->save_proc; SlWriteUint32(ch->id); DEBUG(misc, 1) ("[Sl] Saving chunk %c%c%c%c", ch->id >> 24, ch->id >> 16, ch->id >> 8, ch->id); if (ch->flags & CH_AUTO_LENGTH) { // Need to calculate the length. Solve that by calling SlAutoLength in the save_proc. _tmp_proc_1 = proc; proc = SlStubSaveProc; } _sl.block_mode = ch->flags & CH_TYPE_MASK; switch (ch->flags & CH_TYPE_MASK) { case CH_RIFF: _sl.need_length = NL_WANTLENGTH; proc(); break; case CH_ARRAY: _sl.last_array_index = 0; SlWriteByte(CH_ARRAY); proc(); SlWriteArrayLength(0); // Terminate arrays break; case CH_SPARSE_ARRAY: SlWriteByte(CH_SPARSE_ARRAY); proc(); SlWriteArrayLength(0); // Terminate arrays break; default: NOT_REACHED(); } } /** Save all chunks */ static void SlSaveChunks(void) { const ChunkHandler *ch; const ChunkHandler* const *chsc; uint p; for (p = 0; p != CH_NUM_PRI_LEVELS; p++) { for (chsc = _sl.chs; (ch = *chsc++) != NULL;) { while (true) { if (((ch->flags >> CH_PRI_SHL) & (CH_NUM_PRI_LEVELS - 1)) == p) SlSaveChunk(ch); if (ch->flags & CH_LAST) break; ch++; } } } // Terminator SlWriteUint32(0); } /** Find the ChunkHandler that will be used for processing the found * chunk in the savegame or in memory * @param id the chunk in question * @return returns the appropiate chunkhandler */ static const ChunkHandler *SlFindChunkHandler(uint32 id) { const ChunkHandler *ch; const ChunkHandler *const *chsc; for (chsc = _sl.chs; (ch=*chsc++) != NULL;) { for (;;) { if (ch->id == id) return ch; if (ch->flags & CH_LAST) break; ch++; } } return NULL; } /** Load all chunks */ static void SlLoadChunks(void) { uint32 id; const ChunkHandler *ch; for (id = SlReadUint32(); id != 0; id = SlReadUint32()) { DEBUG(misc, 1) ("[Sl] Loading chunk %c%c%c%c", id >> 24, id >> 16, id >> 8, id); ch = SlFindChunkHandler(id); if (ch == NULL) SlError("found unknown tag in savegame (sync error)"); SlLoadChunk(ch); } } //******************************************* //********** START OF LZO CODE ************** //******************************************* #define LZO_SIZE 8192 #include "minilzo.h" static uint ReadLZO(void) { byte out[LZO_SIZE + LZO_SIZE / 64 + 16 + 3 + 8]; uint32 tmp[2]; uint32 size; uint len; // Read header if (fread(tmp, sizeof(tmp), 1, _sl.fh) != 1) SlError("file read failed"); // Check if size is bad ((uint32*)out)[0] = size = tmp[1]; if (_sl_version != 0) { tmp[0] = TO_BE32(tmp[0]); size = TO_BE32(size); } if (size >= sizeof(out)) SlError("inconsistent size"); // Read block if (fread(out + sizeof(uint32), size, 1, _sl.fh) != 1) SlError("file read failed"); // Verify checksum if (tmp[0] != lzo_adler32(0, out, size + sizeof(uint32))) SlError("bad checksum"); // Decompress lzo1x_decompress(out + sizeof(uint32)*1, size, _sl.buf, &len, NULL); return len; } // p contains the pointer to the buffer, len contains the pointer to the length. // len bytes will be written, p and l will be updated to reflect the next buffer. static void WriteLZO(uint size) { byte out[LZO_SIZE + LZO_SIZE / 64 + 16 + 3 + 8]; byte wrkmem[sizeof(byte*)*4096]; uint outlen; lzo1x_1_compress(_sl.buf, size, out + sizeof(uint32)*2, &outlen, wrkmem); ((uint32*)out)[1] = TO_BE32(outlen); ((uint32*)out)[0] = TO_BE32(lzo_adler32(0, out + sizeof(uint32), outlen + sizeof(uint32))); if (fwrite(out, outlen + sizeof(uint32)*2, 1, _sl.fh) != 1) SlError("file write failed"); } static bool InitLZO(void) { _sl.bufsize = LZO_SIZE; _sl.buf = _sl.buf_ori = (byte*)malloc(LZO_SIZE); return true; } static void UninitLZO(void) { free(_sl.buf_ori); } //********************************************* //******** START OF NOCOMP CODE (uncompressed)* //********************************************* static uint ReadNoComp(void) { return fread(_sl.buf, 1, LZO_SIZE, _sl.fh); } static void WriteNoComp(uint size) { fwrite(_sl.buf, 1, size, _sl.fh); } static bool InitNoComp(void) { _sl.bufsize = LZO_SIZE; _sl.buf = _sl.buf_ori =(byte*)malloc(LZO_SIZE); return true; } static void UninitNoComp(void) { free(_sl.buf_ori); } //******************************************** //********** START OF MEMORY CODE (in ram)**** //******************************************** enum { SAVE_POOL_BLOCK_SIZE_BITS = 17, SAVE_POOL_MAX_BLOCKS = 500 }; #include "network.h" #include "table/strings.h" #include "table/sprites.h" #include "gfx.h" #include "gui.h" typedef struct ThreadedSave { MemoryPool *save; uint count; bool ff_state; bool saveinprogress; CursorID cursor; } ThreadedSave; /* A maximum size of of 128K * 500 = 64.000KB savegames */ static MemoryPool _save_pool = {"Savegame", SAVE_POOL_MAX_BLOCKS, SAVE_POOL_BLOCK_SIZE_BITS, sizeof(byte), NULL, 0, 0, NULL}; static ThreadedSave _ts; static bool InitMem(void) { _ts.save = &_save_pool; _ts.count = 0; CleanPool(_ts.save); AddBlockToPool(_ts.save); /* A block from the pool is a contigious area of memory, so it is safe to write to it sequentially */ _sl.bufsize = _ts.save->total_items; _sl.buf = (byte*)GetItemFromPool(_ts.save, _ts.count); return true; } static void UnInitMem(void) { CleanPool(_ts.save); _ts.save = NULL; } static void WriteMem(uint size) { _ts.count += size; /* Allocate new block and new buffer-pointer */ AddBlockIfNeeded(_ts.save, _ts.count); _sl.buf = (byte*)GetItemFromPool(_ts.save, _ts.count); } //******************************************** //********** START OF ZLIB CODE ************** //******************************************** #if defined(WITH_ZLIB) #include <zlib.h> static z_stream _z; static bool InitReadZlib(void) { memset(&_z, 0, sizeof(_z)); if (inflateInit(&_z) != Z_OK) return false; _sl.bufsize = 4096; _sl.buf = _sl.buf_ori = (byte*)malloc(4096 + 4096); // also contains fread buffer return true; } static uint ReadZlib(void) { int r; _z.next_out = _sl.buf; _z.avail_out = 4096; do { // read more bytes from the file? if (_z.avail_in == 0) { _z.avail_in = fread(_z.next_in = _sl.buf + 4096, 1, 4096, _sl.fh); } // inflate the data r = inflate(&_z, 0); if (r == Z_STREAM_END) break; if (r != Z_OK) SlError("inflate() failed"); } while (_z.avail_out); return 4096 - _z.avail_out; } static void UninitReadZlib(void) { inflateEnd(&_z); free(_sl.buf_ori); } static bool InitWriteZlib(void) { memset(&_z, 0, sizeof(_z)); if (deflateInit(&_z, 6) != Z_OK) return false; _sl.bufsize = 4096; _sl.buf = _sl.buf_ori = (byte*)malloc(4096); // also contains fread buffer return true; } static void WriteZlibLoop(z_streamp z, byte *p, uint len, int mode) { byte buf[1024]; // output buffer int r; uint n; z->next_in = p; z->avail_in = len; do { z->next_out = buf; z->avail_out = sizeof(buf); r = deflate(z, mode); // bytes were emitted? if ((n=sizeof(buf) - z->avail_out) != 0) { if (fwrite(buf, n, 1, _sl.fh) != 1) SlError("file write error"); } if (r == Z_STREAM_END) break; if (r != Z_OK) SlError("zlib returned error code"); } while (z->avail_in || !z->avail_out); } static void WriteZlib(uint len) { WriteZlibLoop(&_z, _sl.buf, len, 0); } static void UninitWriteZlib(void) { // flush any pending output. if (_sl.fh) WriteZlibLoop(&_z, NULL, 0, Z_FINISH); deflateEnd(&_z); free(_sl.buf_ori); } #endif /* WITH_ZLIB */ //******************************************* //************* END OF CODE ***************** //******************************************* // these define the chunks extern const ChunkHandler _misc_chunk_handlers[]; extern const ChunkHandler _setting_chunk_handlers[]; extern const ChunkHandler _player_chunk_handlers[]; extern const ChunkHandler _engine_chunk_handlers[]; extern const ChunkHandler _veh_chunk_handlers[]; extern const ChunkHandler _waypoint_chunk_handlers[]; extern const ChunkHandler _depot_chunk_handlers[]; extern const ChunkHandler _order_chunk_handlers[]; extern const ChunkHandler _town_chunk_handlers[]; extern const ChunkHandler _sign_chunk_handlers[]; extern const ChunkHandler _station_chunk_handlers[]; extern const ChunkHandler _industry_chunk_handlers[]; extern const ChunkHandler _economy_chunk_handlers[]; extern const ChunkHandler _animated_tile_chunk_handlers[]; static const ChunkHandler * const _chunk_handlers[] = { _misc_chunk_handlers, _setting_chunk_handlers, _veh_chunk_handlers, _waypoint_chunk_handlers, _depot_chunk_handlers, _order_chunk_handlers, _industry_chunk_handlers, _economy_chunk_handlers, _engine_chunk_handlers, _town_chunk_handlers, _sign_chunk_handlers, _station_chunk_handlers, _player_chunk_handlers, _animated_tile_chunk_handlers, NULL, }; // used to include a vehicle desc in another desc. extern const SaveLoad _common_veh_desc[]; static const SaveLoad* const _desc_includes[] = { _common_veh_desc }; /** * Pointers cannot be saved to a savegame, so this functions gets * the index of the item, and if not available, it hussles with * pointers (looks really bad :() * Remember that a NULL item has value 0, and all * indeces have +1, so vehicle 0 is saved as index 1. * @param obj The object that we want to get the index of * @param rt @SLRefType type of the object the index is being sought of * @return Return the pointer converted to an index of the type pointed to */ static uint ReferenceToInt(const void *obj, SLRefType rt) { if (obj == NULL) return 0; switch (rt) { case REF_VEHICLE_OLD: // Old vehicles we save as new onces case REF_VEHICLE: return ((const Vehicle*)obj)->index + 1; case REF_STATION: return ((const Station*)obj)->index + 1; case REF_TOWN: return ((const Town*)obj)->index + 1; case REF_ORDER: return ((const Order*)obj)->index + 1; case REF_ROADSTOPS: return ((const RoadStop*)obj)->index + 1; case REF_ENGINE_RENEWS: return ((const EngineRenew*)obj)->index + 1; default: NOT_REACHED(); } return 0; // avoid compiler warning } /** * Pointers cannot be loaded from a savegame, so this function * gets the index from the savegame and returns the appropiate * pointer from the already loaded base. * Remember that an index of 0 is a NULL pointer so all indeces * are +1 so vehicle 0 is saved as 1. * @param index The index that is being converted to a pointer * @param rt @SLRefType type of the object the pointer is sought of * @return Return the index converted to a pointer of any type */ static void *IntToReference(uint index, SLRefType rt) { /* After version 4.3 REF_VEHICLE_OLD is saved as REF_VEHICLE, * and should be loaded like that */ if (rt == REF_VEHICLE_OLD && !CheckSavegameVersionOldStyle(4, 4)) rt = REF_VEHICLE; /* No need to look up NULL pointers, just return immediately */ if (rt != REF_VEHICLE_OLD && index == 0) return NULL; index--; // correct for the NULL index switch (rt) { case REF_ORDER: { if (!AddBlockIfNeeded(&_order_pool, index)) error("Orders: failed loading savegame: too many orders"); return GetOrder(index); } case REF_VEHICLE: { if (!AddBlockIfNeeded(&_vehicle_pool, index)) error("Vehicles: failed loading savegame: too many vehicles"); return GetVehicle(index); } case REF_STATION: { if (!AddBlockIfNeeded(&_station_pool, index)) error("Stations: failed loading savegame: too many stations"); return GetStation(index); } case REF_TOWN: { if (!AddBlockIfNeeded(&_town_pool, index)) error("Towns: failed loading savegame: too many towns"); return GetTown(index); } case REF_ROADSTOPS: { if (!AddBlockIfNeeded(&_roadstop_pool, index)) error("RoadStops: failed loading savegame: too many RoadStops"); return GetRoadStop(index); } case REF_ENGINE_RENEWS: { if (!AddBlockIfNeeded(&_engine_renew_pool, index)) error("EngineRenews: failed loading savegame: too many EngineRenews"); return GetEngineRenew(index); } case REF_VEHICLE_OLD: { /* Old vehicles were saved differently: * invalid vehicle was 0xFFFF, * and the index was not - 1.. correct for this */ index++; if (index == INVALID_VEHICLE) return NULL; if (!AddBlockIfNeeded(&_vehicle_pool, index)) error("Vehicles: failed loading savegame: too many vehicles"); return GetVehicle(index); } default: NOT_REACHED(); } return NULL; } /** The format for a reader/writer type of a savegame */ typedef struct { const char *name; /// name of the compressor/decompressor (debug-only) uint32 tag; /// the 4-letter tag by which it is identified in the savegame bool (*init_read)(void); /// function executed upon initalization of the loader ReaderProc *reader; /// function that loads the data from the file void (*uninit_read)(void); /// function executed when reading is finished bool (*init_write)(void); /// function executed upon intialization of the saver WriterProc *writer; /// function that saves the data to the file void (*uninit_write)(void); /// function executed when writing is done } SaveLoadFormat; static const SaveLoadFormat _saveload_formats[] = { {"memory", 0, NULL, NULL, NULL, InitMem, WriteMem, UnInitMem}, {"lzo", TO_BE32X('OTTD'), InitLZO, ReadLZO, UninitLZO, InitLZO, WriteLZO, UninitLZO}, {"none", TO_BE32X('OTTN'), InitNoComp, ReadNoComp, UninitNoComp, InitNoComp, WriteNoComp, UninitNoComp}, #if defined(WITH_ZLIB) {"zlib", TO_BE32X('OTTZ'), InitReadZlib, ReadZlib, UninitReadZlib, InitWriteZlib, WriteZlib, UninitWriteZlib}, #else {"zlib", TO_BE32X('OTTZ'), NULL, NULL, NULL, NULL, NULL, NULL}, #endif }; /** * Return the savegameformat of the game. Whether it was create with ZLIB compression * uncompressed, or another type * @param s Name of the savegame format. If NULL it picks the first available one * @return Pointer to @SaveLoadFormat struct giving all characteristics of this type of savegame */ static const SaveLoadFormat *GetSavegameFormat(const char *s) { const SaveLoadFormat *def = endof(_saveload_formats) - 1; // find default savegame format, the highest one with which files can be written while (!def->init_write) def--; if (s != NULL && s[0] != '\0') { const SaveLoadFormat *slf; for (slf = &_saveload_formats[0]; slf != endof(_saveload_formats); slf++) { if (slf->init_write != NULL && strcmp(s, slf->name) == 0) return slf; } ShowInfoF("Savegame format '%s' is not available. Reverting to '%s'.", s, def->name); } return def; } // actual loader/saver function void InitializeGame(int mode, uint size_x, uint size_y); extern bool AfterLoadGame(void); extern void BeforeSaveGame(void); extern bool LoadOldSaveGame(const char *file); /** Small helper function to close the to be loaded savegame an signal error */ static inline SaveOrLoadResult AbortSaveLoad(void) { if (_sl.fh != NULL) fclose(_sl.fh); _sl.fh = NULL; return SL_ERROR; } /** Update the gui accordingly when starting saving * and set locks on saveload. Also turn off fast-forward cause with that * saving takes Aaaaages */ void SaveFileStart(void) { _ts.ff_state = _fast_forward; _fast_forward = false; if (_cursor.sprite == SPR_CURSOR_MOUSE) SetMouseCursor(SPR_CURSOR_ZZZ); SendWindowMessage(WC_STATUS_BAR, 0, true, 0, 0); _ts.saveinprogress = true; } /** Update the gui accordingly when saving is done and release locks * on saveload */ void SaveFileDone(void) { _fast_forward = _ts.ff_state; if (_cursor.sprite == SPR_CURSOR_ZZZ) SetMouseCursor(SPR_CURSOR_MOUSE); SendWindowMessage(WC_STATUS_BAR, 0, false, 0, 0); _ts.saveinprogress = false; } /** Show a gui message when saving has failed */ void SaveFileError(void) { ShowErrorMessage(STR_4007_GAME_SAVE_FAILED, STR_NULL, 0, 0); SaveFileDone(); } static Thread* save_thread; /** We have written the whole game into memory, _save_pool, now find * and appropiate compressor and start writing to file. */ static void* SaveFileToDisk(void *arg) { const SaveLoadFormat *fmt; uint32 hdr[2]; if (arg != NULL) OTTD_SendThreadMessage(MSG_OTTD_SAVETHREAD_START); /* XXX - Setup setjmp error handler if an error occurs anywhere deep during * loading/saving execute a longjmp() and continue execution here */ if (setjmp(_sl.excpt)) { AbortSaveLoad(); _sl.excpt_uninit(); fprintf(stderr, "Save game failed: %s.", _sl.excpt_msg); if (arg != NULL) OTTD_SendThreadMessage(MSG_OTTD_SAVETHREAD_ERROR); else SaveFileError(); return NULL; } fmt = GetSavegameFormat(_savegame_format); /* We have written our stuff to memory, now write it to file! */ hdr[0] = fmt->tag; hdr[1] = TO_BE32(SAVEGAME_VERSION << 16); if (fwrite(hdr, sizeof(hdr), 1, _sl.fh) != 1) SlError("file write failed"); if (!fmt->init_write()) SlError("cannot initialize compressor"); { uint i; uint count = 1 << _ts.save->block_size_bits; assert(_ts.count == _sl.offs_base); for (i = 0; i != _ts.save->current_blocks - 1; i++) { _sl.buf = _ts.save->blocks[i]; fmt->writer(count); } /* The last block is (almost) always not fully filled, so only write away * as much data as it is in there */ _sl.buf = _ts.save->blocks[i]; fmt->writer(_ts.count - (i * count)); } fmt->uninit_write(); assert(_ts.count == _sl.offs_base); GetSavegameFormat("memory")->uninit_write(); // clean the memorypool fclose(_sl.fh); if (arg != NULL) OTTD_SendThreadMessage(MSG_OTTD_SAVETHREAD_DONE); return NULL; } void WaitTillSaved(void) { OTTDJoinThread(save_thread); save_thread = NULL; } /** * Main Save or Load function where the high-level saveload functions are * handled. It opens the savegame, selects format and checks versions * @param filename The name of the savegame being created/loaded * @param mode Save or load. Load can also be a TTD(Patch) game. Use SL_LOAD, SL_OLD_LOAD or SL_SAVE * @return Return the results of the action. SL_OK, SL_ERROR or SL_REINIT ("unload" the game) */ SaveOrLoadResult SaveOrLoad(const char *filename, int mode) { uint32 hdr[2]; const SaveLoadFormat *fmt; uint version; /* An instance of saving is already active, so don't go saving again */ if (_ts.saveinprogress && mode == SL_SAVE) { // if not an autosave, but a user action, show error message if (!_do_autosave) ShowErrorMessage(INVALID_STRING_ID, STR_SAVE_STILL_IN_PROGRESS, 0, 0); return SL_OK; } WaitTillSaved(); /* Load a TTDLX or TTDPatch game */ if (mode == SL_OLD_LOAD) { InitializeGame(IG_DATE_RESET, 256, 256); // set a mapsize of 256x256 for TTDPatch games or it might get confused if (!LoadOldSaveGame(filename)) return SL_REINIT; _sl_version = 0; AfterLoadGame(); return SL_OK; } _sl.fh = (mode == SL_SAVE) ? fopen(OTTD2FS(filename), "wb") : fopen(filename, "rb"); if (_sl.fh == NULL) { DEBUG(misc, 0) ("[Sl] Cannot open savegame for saving/loading."); return SL_ERROR; } _sl.bufe = _sl.bufp = NULL; _sl.offs_base = 0; _sl.int_to_ref_proc = IntToReference; _sl.ref_to_int_proc = ReferenceToInt; _sl.save = mode; _sl.includes = _desc_includes; _sl.chs = _chunk_handlers; /* XXX - Setup setjmp error handler if an error occurs anywhere deep during * loading/saving execute a longjmp() and continue execution here */ if (setjmp(_sl.excpt)) { AbortSaveLoad(); // deinitialize compressor. _sl.excpt_uninit(); /* A saver/loader exception!! reinitialize all variables to prevent crash! */ if (mode == SL_LOAD) { ShowInfoF("Load game failed: %s.", _sl.excpt_msg); return SL_REINIT; } ShowInfoF("Save game failed: %s.", _sl.excpt_msg); return SL_ERROR; } /* We first initialize here to avoid: "warning: variable `version' might * be clobbered by `longjmp' or `vfork'" */ version = 0; /* General tactic is to first save the game to memory, then use an available writer * to write it to file, either in threaded mode if possible, or single-threaded */ if (mode == SL_SAVE) { /* SAVE game */ fmt = GetSavegameFormat("memory"); // write to memory _sl.write_bytes = fmt->writer; _sl.excpt_uninit = fmt->uninit_write; if (!fmt->init_write()) { DEBUG(misc, 0) ("[Sl] Initializing writer %s failed.", fmt->name); return AbortSaveLoad(); } _sl_version = SAVEGAME_VERSION; BeforeSaveGame(); SlSaveChunks(); SlWriteFill(); // flush the save buffer if (_network_server || (save_thread = OTTDCreateThread(&SaveFileToDisk, (void*)"")) == NULL) { DEBUG(misc, 1) ("[Sl] Cannot create savegame thread, reverting to single-threaded mode..."); SaveFileToDisk(NULL); } } else { /* LOAD game */ assert(mode == SL_LOAD); if (fread(hdr, sizeof(hdr), 1, _sl.fh) != 1) { DEBUG(misc, 0) ("[Sl] Cannot read savegame header, aborting."); return AbortSaveLoad(); } // see if we have any loader for this type. for (fmt = _saveload_formats; ; fmt++) { /* No loader found, treat as version 0 and use LZO format */ if (fmt == endof(_saveload_formats)) { DEBUG(misc, 0) ("[Sl] Unknown savegame type, trying to load it as the buggy format."); rewind(_sl.fh); _sl_version = version = 0; _sl_minor_version = 0; fmt = _saveload_formats + 1; // LZO break; } if (fmt->tag == hdr[0]) { // check version number _sl_version = version = TO_BE32(hdr[1]) >> 16; /* Minor is not used anymore from version 18.0, but it is still needed * in versions before that (4 cases) which can't be removed easy. * Therefor it is loaded, but never saved (or, it saves a 0 in any scenario). * So never EVER use this minor version again. -- TrueLight -- 22-11-2005 */ _sl_minor_version = (TO_BE32(hdr[1]) >> 8) & 0xFF; DEBUG(misc, 1)("[Sl] Loading savegame version %d", _sl_version); /* Is the version higher than the current? */ if (_sl_version > SAVEGAME_VERSION) { DEBUG(misc, 0) ("[Sl] Savegame version invalid."); return AbortSaveLoad(); } break; } } _sl.read_bytes = fmt->reader; _sl.excpt_uninit = fmt->uninit_read; // loader for this savegame type is not implemented? if (fmt->init_read == NULL) { ShowInfoF("Loader for '%s' is not available.", fmt->name); return AbortSaveLoad(); } if (!fmt->init_read()) { DEBUG(misc, 0) ("[Sl] Initializing loader %s failed.", fmt->name); return AbortSaveLoad(); } /* Old maps were hardcoded to 256x256 and thus did not contain * any mapsize information. Pre-initialize to 256x256 to not to * confuse old games */ InitializeGame(IG_DATE_RESET, 256, 256); SlLoadChunks(); fmt->uninit_read(); fclose(_sl.fh); /* After loading fix up savegame for any internal changes that * might've occured since then. If it fails, load back the old game */ if (!AfterLoadGame()) return SL_REINIT; } return SL_OK; } /** Do a save when exiting the game (patch option) _patches.autosave_on_exit */ void DoExitSave(void) { char buf[200]; snprintf(buf, sizeof(buf), "%s%sexit.sav", _path.autosave_dir, PATHSEP); SaveOrLoad(buf, SL_SAVE); } #if 0 /** * Function to get the type of the savegame by looking at the file header. * NOTICE: Not used right now, but could be used if extensions of savegames are garbled * @param file Savegame to be checked * @return SL_OLD_LOAD or SL_LOAD of the file */ int GetSavegameType(char *file) { const SaveLoadFormat *fmt; uint32 hdr; FILE *f; int mode = SL_OLD_LOAD; f = fopen(file, "rb"); if (fread(&hdr, sizeof(hdr), 1, f) != 1) { printf("Savegame is obsolete or invalid format.\n"); mode = SL_LOAD; // don't try to get filename, just show name as it is written } else { // see if we have any loader for this type. for (fmt = _saveload_formats; fmt != endof(_saveload_formats); fmt++) { if (fmt->tag == hdr) { mode = SL_LOAD; // new type of savegame break; } } } fclose(f); return mode; } #endif