diff options
Diffstat (limited to 'src/mongo/db/storage/mmap_v1/aligned_builder.h')
| -rw-r--r-- | src/mongo/db/storage/mmap_v1/aligned_builder.h | 211 |
1 files changed, 112 insertions, 99 deletions
diff --git a/src/mongo/db/storage/mmap_v1/aligned_builder.h b/src/mongo/db/storage/mmap_v1/aligned_builder.h index fb184424b66..f43cbee7d5d 100644 --- a/src/mongo/db/storage/mmap_v1/aligned_builder.h +++ b/src/mongo/db/storage/mmap_v1/aligned_builder.h @@ -33,104 +33,117 @@ namespace mongo { - /** a page-aligned BufBuilder. */ - class AlignedBuilder { - public: - AlignedBuilder(unsigned init_size); - ~AlignedBuilder() { kill(); } - - /** reset with a hint as to the upcoming needed size specified */ - void reset(unsigned sz); - - /** reset for a re-use. shrinks if > 128MB */ - void reset(); - - /** note this may be deallocated (realloced) if you keep writing or reset(). */ - const char* buf() const { return _p._data; } - - /** leave room for some stuff later - @return offset in the buffer that was our current position - */ - size_t skip(unsigned n) { - unsigned l = len(); - grow(n); - return l; +/** a page-aligned BufBuilder. */ +class AlignedBuilder { +public: + AlignedBuilder(unsigned init_size); + ~AlignedBuilder() { + kill(); + } + + /** reset with a hint as to the upcoming needed size specified */ + void reset(unsigned sz); + + /** reset for a re-use. shrinks if > 128MB */ + void reset(); + + /** note this may be deallocated (realloced) if you keep writing or reset(). */ + const char* buf() const { + return _p._data; + } + + /** leave room for some stuff later + @return offset in the buffer that was our current position + */ + size_t skip(unsigned n) { + unsigned l = len(); + grow(n); + return l; + } + + /** if buffer grows pointer no longer valid */ + char* atOfs(unsigned ofs) { + return _p._data + ofs; + } + + /** if buffer grows pointer no longer valid */ + char* cur() { + return _p._data + _len; + } + + void appendChar(char j) { + *((char*)grow(sizeof(char))) = j; + } + void appendNum(char j) { + *((char*)grow(sizeof(char))) = j; + } + void appendNum(short j) { + *((short*)grow(sizeof(short))) = j; + } + void appendNum(int j) { + *((int*)grow(sizeof(int))) = j; + } + void appendNum(unsigned j) { + *((unsigned*)grow(sizeof(unsigned))) = j; + } + void appendNum(bool j) { + *((bool*)grow(sizeof(bool))) = j; + } + void appendNum(double j) { + *((double*)grow(sizeof(double))) = j; + } + void appendNum(long long j) { + *((long long*)grow(sizeof(long long))) = j; + } + void appendNum(unsigned long long j) { + *((unsigned long long*)grow(sizeof(unsigned long long))) = j; + } + + void appendBuf(const void* src, size_t len) { + memcpy(grow((unsigned)len), src, len); + } + + template <class T> + void appendStruct(const T& s) { + appendBuf(&s, sizeof(T)); + } + + void appendStr(StringData str, bool includeEOO = true) { + const unsigned len = str.size() + (includeEOO ? 1 : 0); + verify(len < (unsigned)BSONObjMaxUserSize); + str.copyTo(grow(len), includeEOO); + } + + /** @return the in-use length */ + unsigned len() const { + return _len; + } + +private: + static const unsigned Alignment = 8192; + + /** returns the pre-grow write position */ + inline char* grow(unsigned by) { + unsigned oldlen = _len; + _len += by; + if (MONGO_unlikely(_len > _p._size)) { + growReallocate(oldlen); } - - /** if buffer grows pointer no longer valid */ - char* atOfs(unsigned ofs) { return _p._data + ofs; } - - /** if buffer grows pointer no longer valid */ - char* cur() { return _p._data + _len; } - - void appendChar(char j) { - *((char*)grow(sizeof(char))) = j; - } - void appendNum(char j) { - *((char*)grow(sizeof(char))) = j; - } - void appendNum(short j) { - *((short*)grow(sizeof(short))) = j; - } - void appendNum(int j) { - *((int*)grow(sizeof(int))) = j; - } - void appendNum(unsigned j) { - *((unsigned*)grow(sizeof(unsigned))) = j; - } - void appendNum(bool j) { - *((bool*)grow(sizeof(bool))) = j; - } - void appendNum(double j) { - *((double*)grow(sizeof(double))) = j; - } - void appendNum(long long j) { - *((long long*)grow(sizeof(long long))) = j; - } - void appendNum(unsigned long long j) { - *((unsigned long long*)grow(sizeof(unsigned long long))) = j; - } - - void appendBuf(const void *src, size_t len) { memcpy(grow((unsigned) len), src, len); } - - template<class T> - void appendStruct(const T& s) { appendBuf(&s, sizeof(T)); } - - void appendStr(StringData str , bool includeEOO = true ) { - const unsigned len = str.size() + ( includeEOO ? 1 : 0 ); - verify( len < (unsigned) BSONObjMaxUserSize ); - str.copyTo( grow(len), includeEOO ); - } - - /** @return the in-use length */ - unsigned len() const { return _len; } - - private: - static const unsigned Alignment = 8192; - - /** returns the pre-grow write position */ - inline char* grow(unsigned by) { - unsigned oldlen = _len; - _len += by; - if (MONGO_unlikely( _len > _p._size )) { - growReallocate(oldlen); - } - return _p._data + oldlen; - } - - void growReallocate(unsigned oldLenInUse); - void kill(); - void mallocSelfAligned(unsigned sz); - void _malloc(unsigned sz); - void _realloc(unsigned newSize, unsigned oldLenInUse); - void _free(void*); - - struct AllocationInfo { - char *_data; - void *_allocationAddress; - unsigned _size; - } _p; - unsigned _len; // bytes in use - }; - + return _p._data + oldlen; + } + + void growReallocate(unsigned oldLenInUse); + void kill(); + void mallocSelfAligned(unsigned sz); + void _malloc(unsigned sz); + void _realloc(unsigned newSize, unsigned oldLenInUse); + void _free(void*); + + struct AllocationInfo { + char* _data; + void* _allocationAddress; + unsigned _size; + } _p; + unsigned _len; // bytes in use +}; } |