(svn r15174) -Codechange: split oldloader.cpp

1 files changed, 124 insertions, 0 deletions

diff --git a/src/saveload/oldloader.h b/src/saveload/oldloader.h
new file mode 100644
index 000000000..5cde06cc5
--- /dev/null
+++ b/src/saveload/oldloader.h
@@ -0,0 +1,124 @@
+/* $Id$ */
+
+/** @file oldloader.h Declarations of strctures and function used in loader of old savegames */
+
+#ifndef OLDLOADER_H
+#define OLDLOADER_H
+
+#include "saveload.h"
+
+enum {
+	BUFFER_SIZE = 4096,
+	OLD_MAP_SIZE = 256 * 256,
+};
+
+struct LoadgameState {
+	FILE *file;
+
+	uint chunk_size;
+
+	bool decoding;
+	byte decode_char;
+
+	uint buffer_count;
+	uint buffer_cur;
+	byte buffer[BUFFER_SIZE];
+
+	uint total_read;
+	bool failed;
+};
+
+/* OldChunk-Type */
+enum OldChunkType {
+	OC_SIMPLE    = 0,
+	OC_NULL      = 1,
+	OC_CHUNK     = 2,
+	OC_ASSERT    = 3,
+	/* 8 bits allocated (256 max) */
+
+	OC_VAR_I8    = 1 << 8,
+	OC_VAR_U8    = 2 << 8,
+	OC_VAR_I16   = 3 << 8,
+	OC_VAR_U16   = 4 << 8,
+	OC_VAR_I32   = 5 << 8,
+	OC_VAR_U32   = 6 << 8,
+	OC_VAR_I64   = 7 << 8,
+	/* 8 bits allocated (256 max) */
+
+	OC_FILE_I8   = 1 << 16,
+	OC_FILE_U8   = 2 << 16,
+	OC_FILE_I16  = 3 << 16,
+	OC_FILE_U16  = 4 << 16,
+	OC_FILE_I32  = 5 << 16,
+	OC_FILE_U32  = 6 << 16,
+	/* 8 bits allocated (256 max) */
+
+	OC_INT8      = OC_VAR_I8   | OC_FILE_I8,
+	OC_UINT8     = OC_VAR_U8   | OC_FILE_U8,
+	OC_INT16     = OC_VAR_I16  | OC_FILE_I16,
+	OC_UINT16    = OC_VAR_U16  | OC_FILE_U16,
+	OC_INT32     = OC_VAR_I32  | OC_FILE_I32,
+	OC_UINT32    = OC_VAR_U32  | OC_FILE_U32,
+
+	OC_TILE      = OC_VAR_U32  | OC_FILE_U16,
+
+	/**
+	 * Dereference the pointer once before writing to it,
+	 * so we do not have to use big static arrays.
+	 */
+	OC_DEREFERENCE_POINTER = 1 << 31,
+
+	OC_END       = 0 ///< End of the whole chunk, all 32 bits set to zero
+};
+
+DECLARE_ENUM_AS_BIT_SET(OldChunkType);
+
+typedef bool OldChunkProc(LoadgameState *ls, int num);
+
+struct OldChunks {
+	OldChunkType type;   ///< Type of field
+	uint32 amount;       ///< Amount of fields
+
+	void *ptr;           ///< Pointer where to save the data (may only be set if offset is 0)
+	uint offset;         ///< Offset from basepointer (may only be set if ptr is NULL)
+	OldChunkProc *proc;  ///< Pointer to function that is called with OC_CHUNK
+};
+
+/* If it fails, check lines above.. */
+assert_compile(sizeof(TileIndex) == 4);
+
+extern uint _bump_assert_value;
+byte ReadByte(LoadgameState *ls);
+bool LoadChunk(LoadgameState *ls, void *base, const OldChunks *chunks);
+
+bool LoadOldMain(LoadgameState *ls);
+
+static inline uint16 ReadUint16(LoadgameState *ls)
+{
+	byte x = ReadByte(ls);
+	return x | ReadByte(ls) << 8;
+}
+
+static inline uint32 ReadUint32(LoadgameState *ls)
+{
+	uint16 x = ReadUint16(ls);
+	return x | ReadUint16(ls) << 16;
+}
+
+/* Help:
+ *  - OCL_SVAR: load 'type' to offset 'offset' in a struct of type 'base', which must also
+ *       be given via base in LoadChunk() as real pointer
+ *  - OCL_VAR: load 'type' to a global var
+ *  - OCL_END: every struct must end with this
+ *  - OCL_NULL: read 'amount' of bytes and send them to /dev/null or something
+ *  - OCL_CHUNK: load an other proc to load a part of the savegame, 'amount' times
+ *  - OCL_ASSERT: to check if we are really at the place we expect to be.. because old savegames are too binary to be sure ;)
+ */
+#define OCL_SVAR(type, base, offset)         { type,          1, NULL,    (uint)cpp_offsetof(base, offset), NULL }
+#define OCL_VAR(type, amount, pointer)       { type,     amount, pointer, 0,                      NULL }
+#define OCL_END()                                   { OC_END,        0, NULL,    0,                      NULL }
+#define OCL_NULL(amount)                            { OC_NULL,  amount, NULL,    0,                      NULL }
+#define OCL_CHUNK(amount, proc)                     { OC_CHUNK, amount, NULL,    0,                      proc }
+#define OCL_ASSERT(size)                            { OC_ASSERT,     1, NULL, size,                      NULL }
+
+#endif /* OLDLOADER_H */