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#pragma once
#include <util/system/defaults.h>
#include <util/generic/typetraits.h>
#include <util/generic/string.h>
#include <util/str_stl.h>
#include <stdio.h>
#define METASIZE (1u << 12)
#define METASIG 0x12345678u
#define PAGESIG 0x87654321u
enum EMbdbErrors {
MBDB_ALREADY_INITIALIZED = 200,
MBDB_NOT_INITIALIZED = 201,
MBDB_BAD_DESCRIPTOR = 202,
MBDB_OPEN_ERROR = 203,
MBDB_READ_ERROR = 204,
MBDB_WRITE_ERROR = 205,
MBDB_CLOSE_ERROR = 206,
MBDB_EXPECTED_EOF = 207,
MBDB_UNEXPECTED_EOF = 208,
MBDB_BAD_FILENAME = 209,
MBDB_BAD_METAPAGE = 210,
MBDB_BAD_RECORDSIG = 211,
MBDB_BAD_FILE_SIZE = 212,
MBDB_BAD_PAGESIG = 213,
MBDB_BAD_PAGESIZE = 214,
MBDB_BAD_PARM = 215,
MBDB_BAD_SYNC = 216,
MBDB_PAGE_OVERFLOW = 217,
MBDB_NO_MEMORY = 218,
MBDB_MEMORY_LEAK = 219,
MBDB_NOT_SUPPORTED = 220
};
TString ToString(EMbdbErrors error);
TString ErrorMessage(int error, const TString& text, const TString& path = TString(), ui32 recordSig = 0, ui32 gotRecordSig = 0);
enum EPageFormat {
MBDB_FORMAT_RAW = 0,
MBDB_FORMAT_COMPRESSED = 1,
MBDB_FORMAT_NULL = 255
};
enum ECompressionAlgorithm {
MBDB_COMPRESSION_ZLIB = 1,
MBDB_COMPRESSION_FASTLZ = 2,
MBDB_COMPRESSION_SNAPPY = 3
};
struct TDatMetaPage {
ui32 MetaSig;
ui32 RecordSig;
ui32 PageSize;
};
struct TDatPage {
ui32 RecNum; //!< number of records on this page
ui32 PageSig;
ui32 Format : 2; //!< one of EPageFormat
ui32 Reserved : 30;
};
/// Additional page header with compression info
struct TCompressedPage {
ui32 BlockCount;
ui32 Algorithm : 4;
ui32 Version : 4;
ui32 Reserved : 24;
};
namespace NMicroBDB {
/// Header of compressed block
struct TCompressedHeader {
ui32 Compressed;
ui32 Original; /// original size of block
ui32 Count; /// number of records in block
ui32 Reserved;
};
Y_HAS_MEMBER(AssertValid);
template <typename T, bool TVal>
struct TAssertValid {
void operator()(const T*) {
}
};
template <typename T>
struct TAssertValid<T, true> {
void operator()(const T* rec) {
return rec->AssertValid();
}
};
template <typename T>
void AssertValid(const T* rec) {
return NMicroBDB::TAssertValid<T, NMicroBDB::THasAssertValid<T>::value>()(rec);
}
Y_HAS_MEMBER(SizeOf);
template <typename T, bool TVal>
struct TGetSizeOf;
template <typename T>
struct TGetSizeOf<T, true> {
size_t operator()(const T* rec) {
return rec->SizeOf();
}
};
template <typename T>
struct TGetSizeOf<T, false> {
size_t operator()(const T*) {
return sizeof(T);
}
};
inline char* GetFirstRecord(const TDatPage* page) {
switch (page->Format) {
case MBDB_FORMAT_RAW:
return (char*)page + sizeof(TDatPage);
case MBDB_FORMAT_COMPRESSED:
// Первая запись на сжатой странице сохраняется несжатой
// сразу же после всех заголовков.
// Алгоритм сохранения смотреть в TOutputRecordIterator::FlushBuffer
return (char*)page + sizeof(TDatPage) + sizeof(TCompressedPage) + sizeof(NMicroBDB::TCompressedHeader);
}
return (char*)nullptr;
}
}
template <typename T>
size_t SizeOf(const T* rec) {
return NMicroBDB::TGetSizeOf<T, NMicroBDB::THasSizeOf<T>::value>()(rec);
}
template <typename T>
size_t MaxSizeOf() {
return sizeof(T);
}
static inline int DatNameToIdx(char iname[/*FILENAME_MAX*/], const char* dname) {
if (!dname || !*dname)
return MBDB_BAD_FILENAME;
const char* ptr;
if (!(ptr = strrchr(dname, '/')))
ptr = dname;
if (!(ptr = strrchr(ptr, '.')))
ptr = strchr(dname, 0);
if (ptr - dname > FILENAME_MAX - 5)
return MBDB_BAD_FILENAME;
memcpy(iname, dname, ptr - dname);
strcpy(iname + (ptr - dname), ".idx");
return 0;
}
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