diff options
Diffstat (limited to 'src/mongo/db/storage/mmap_v1/diskloc.h')
| -rw-r--r-- | src/mongo/db/storage/mmap_v1/diskloc.h | 271 |
1 files changed, 149 insertions, 122 deletions
diff --git a/src/mongo/db/storage/mmap_v1/diskloc.h b/src/mongo/db/storage/mmap_v1/diskloc.h index 9d3adc64da7..662daf074d5 100644 --- a/src/mongo/db/storage/mmap_v1/diskloc.h +++ b/src/mongo/db/storage/mmap_v1/diskloc.h @@ -43,149 +43,176 @@ namespace mongo { - template< class Version > class BtreeBucket; +template <class Version> +class BtreeBucket; #pragma pack(1) - /** represents a disk location/offset on disk in a database. 64 bits. - it is assumed these will be passed around by value a lot so don't do anything to make them large - (such as adding a virtual function) - */ - class DiskLoc { - int _a; // this will be volume, file #, etc. but is a logical value could be anything depending on storage engine - int ofs; - - public: - - enum SentinelValues { - /* note NullOfs is different. todo clean up. see refs to NullOfs in code - use is valid but outside DiskLoc context so confusing as-is. */ - NullOfs = -1, - - // Caps the number of files that may be allocated in a database, allowing about 32TB of - // data per db. Note that the DiskLoc and DiskLoc56Bit types supports more files than - // this value, as does the data storage format. - MaxFiles=16000, - - // How invalid DiskLocs are represented in RecordIds. - InvalidRepr = -2LL, - }; - - DiskLoc(int a, int Ofs) : _a(a), ofs(Ofs) { } - DiskLoc() { Null(); } - - // Minimum allowed DiskLoc. No MmapV1RecordHeader may begin at this location because file and extent - // headers must precede Records in a file. - static DiskLoc min() { return DiskLoc(0, 0); } - - // Maximum allowed DiskLoc. - // No MmapV1RecordHeader may begin at this location because the minimum size of a MmapV1RecordHeader is larger than - // one byte. Also, the last bit is not able to be used because mmapv1 uses that for "used". - static DiskLoc max() { return DiskLoc(0x7fffffff, 0x7ffffffe); } - - bool questionable() const { - return ofs < -1 || - _a < -1 || - _a > 524288; - } +/** represents a disk location/offset on disk in a database. 64 bits. + it is assumed these will be passed around by value a lot so don't do anything to make them large + (such as adding a virtual function) + */ +class DiskLoc { + int _a; // this will be volume, file #, etc. but is a logical value could be anything depending on storage engine + int ofs; + +public: + enum SentinelValues { + /* note NullOfs is different. todo clean up. see refs to NullOfs in code - use is valid but outside DiskLoc context so confusing as-is. */ + NullOfs = -1, + + // Caps the number of files that may be allocated in a database, allowing about 32TB of + // data per db. Note that the DiskLoc and DiskLoc56Bit types supports more files than + // this value, as does the data storage format. + MaxFiles = 16000, + + // How invalid DiskLocs are represented in RecordIds. + InvalidRepr = -2LL, + }; - bool isNull() const { return _a == -1; } - DiskLoc& Null() { - _a = -1; - ofs = 0; /* note NullOfs is different. todo clean up. see refs to NullOfs in code - use is valid but outside DiskLoc context so confusing as-is. */ - return *this; - } - void assertOk() const { verify(!isNull()); } - DiskLoc& setInvalid() { - _a = -2; - ofs = 0; - return *this; - } - bool isValid() const { return _a != -2; } - - std::string toString() const { - if ( isNull() ) - return "null"; - std::stringstream ss; - ss << _a << ':' << std::hex << ofs; - return ss.str(); - } + DiskLoc(int a, int Ofs) : _a(a), ofs(Ofs) {} + DiskLoc() { + Null(); + } - BSONObj toBSONObj() const { return BSON( "file" << _a << "offset" << ofs ); } + // Minimum allowed DiskLoc. No MmapV1RecordHeader may begin at this location because file and extent + // headers must precede Records in a file. + static DiskLoc min() { + return DiskLoc(0, 0); + } - int a() const { return _a; } + // Maximum allowed DiskLoc. + // No MmapV1RecordHeader may begin at this location because the minimum size of a MmapV1RecordHeader is larger than + // one byte. Also, the last bit is not able to be used because mmapv1 uses that for "used". + static DiskLoc max() { + return DiskLoc(0x7fffffff, 0x7ffffffe); + } - int& GETOFS() { return ofs; } - int getOfs() const { return ofs; } - void set(int a, int b) { - _a=a; - ofs=b; - } + bool questionable() const { + return ofs < -1 || _a < -1 || _a > 524288; + } - void inc(int amt) { - verify( !isNull() ); - ofs += amt; - } + bool isNull() const { + return _a == -1; + } + DiskLoc& Null() { + _a = -1; + ofs = + 0; /* note NullOfs is different. todo clean up. see refs to NullOfs in code - use is valid but outside DiskLoc context so confusing as-is. */ + return *this; + } + void assertOk() const { + verify(!isNull()); + } + DiskLoc& setInvalid() { + _a = -2; + ofs = 0; + return *this; + } + bool isValid() const { + return _a != -2; + } - bool sameFile(DiskLoc b) { - return _a== b._a; - } + std::string toString() const { + if (isNull()) + return "null"; + std::stringstream ss; + ss << _a << ':' << std::hex << ofs; + return ss.str(); + } - bool operator==(const DiskLoc& b) const { - return _a==b._a&& ofs == b.ofs; - } - bool operator!=(const DiskLoc& b) const { - return !(*this==b); - } - int compare(const DiskLoc& b) const { - int x = _a - b._a; - if ( x ) - return x; - return ofs - b.ofs; - } + BSONObj toBSONObj() const { + return BSON("file" << _a << "offset" << ofs); + } - static DiskLoc fromRecordId(RecordId id) { - if (id.isNormal()) - return DiskLoc((id.repr() >> 32), uint32_t(id.repr())); + int a() const { + return _a; + } - if (id.isNull()) - return DiskLoc(); + int& GETOFS() { + return ofs; + } + int getOfs() const { + return ofs; + } + void set(int a, int b) { + _a = a; + ofs = b; + } - if (id == RecordId::max()) - return DiskLoc::max(); + void inc(int amt) { + verify(!isNull()); + ofs += amt; + } - if (id == RecordId::min()) - return DiskLoc::min(); + bool sameFile(DiskLoc b) { + return _a == b._a; + } - dassert(id.repr() == InvalidRepr); - return DiskLoc().setInvalid(); - } + bool operator==(const DiskLoc& b) const { + return _a == b._a && ofs == b.ofs; + } + bool operator!=(const DiskLoc& b) const { + return !(*this == b); + } + int compare(const DiskLoc& b) const { + int x = _a - b._a; + if (x) + return x; + return ofs - b.ofs; + } + + static DiskLoc fromRecordId(RecordId id) { + if (id.isNormal()) + return DiskLoc((id.repr() >> 32), uint32_t(id.repr())); - RecordId toRecordId() const { - if (_a >= 0) { - if (*this == DiskLoc::min()) - return RecordId::min(); + if (id.isNull()) + return DiskLoc(); - if (*this == DiskLoc::max()) - return RecordId::max(); + if (id == RecordId::max()) + return DiskLoc::max(); - return RecordId(uint64_t(_a) << 32 | uint32_t(ofs)); - } + if (id == RecordId::min()) + return DiskLoc::min(); + + dassert(id.repr() == InvalidRepr); + return DiskLoc().setInvalid(); + } - if (isNull()) - return RecordId(); + RecordId toRecordId() const { + if (_a >= 0) { + if (*this == DiskLoc::min()) + return RecordId::min(); - dassert(!isValid()); - return RecordId(InvalidRepr); + if (*this == DiskLoc::max()) + return RecordId::max(); + + return RecordId(uint64_t(_a) << 32 | uint32_t(ofs)); } - }; -#pragma pack() - inline bool operator< (const DiskLoc& rhs, const DiskLoc& lhs) { return rhs.compare(lhs) < 0; } - inline bool operator<=(const DiskLoc& rhs, const DiskLoc& lhs) { return rhs.compare(lhs) <= 0; } - inline bool operator> (const DiskLoc& rhs, const DiskLoc& lhs) { return rhs.compare(lhs) > 0; } - inline bool operator>=(const DiskLoc& rhs, const DiskLoc& lhs) { return rhs.compare(lhs) >= 0; } + if (isNull()) + return RecordId(); - inline std::ostream& operator<<( std::ostream &stream, const DiskLoc &loc ) { - return stream << loc.toString(); + dassert(!isValid()); + return RecordId(InvalidRepr); } +}; +#pragma pack() -} // namespace mongo +inline bool operator<(const DiskLoc& rhs, const DiskLoc& lhs) { + return rhs.compare(lhs) < 0; +} +inline bool operator<=(const DiskLoc& rhs, const DiskLoc& lhs) { + return rhs.compare(lhs) <= 0; +} +inline bool operator>(const DiskLoc& rhs, const DiskLoc& lhs) { + return rhs.compare(lhs) > 0; +} +inline bool operator>=(const DiskLoc& rhs, const DiskLoc& lhs) { + return rhs.compare(lhs) >= 0; +} + +inline std::ostream& operator<<(std::ostream& stream, const DiskLoc& loc) { + return stream << loc.toString(); +} + +} // namespace mongo |