/************************************************************************ * @file implementation of variable-sized slotted pages STRUCTURE OF A PAGE
 +-----------------------------------------+-----------------------+----+
 | DATA SECTION                 +--------->| RID: (PAGE, 0)        |    |
 |          +-----------------+ |          +-----------------------+    |
 |      +-->| RID: (PAGE, 1)  | |                                       |
 |      |   +-----------------+ |                                       |
 |      |                       |                                       |
 |      ----------------+       |        +------------------------------+
 |                      |       |   +--->| RID: (PAGE, n)               |
 |                      |       |   |    +------------------------------+
 |======================================================================|
 |  ^ FREE SPACE        |       |   |                                   |
 |  |                   |       |   |                                   |
 |  +-------------------|-------|---|--------------------+              |
 |                      |       |   |                    |              |
 |        +-------------|-------|---+                    |              |
 |        |             |       |                        |              |
 |    +---|---+-----+---|---+---|---+--------------+-----|------+-------+
 |    | slotn | ... | slot1 | slot0 | num of slots | free space |  ***  |
 +----+-------+-----+-------+-------+--------------+------------+-------+
*** = @see page.h for information on this field. NOTE: - slots are zero indexed. - slots are of implemented as (offset, length) Slotted page layout: END: lsn (4 bytes) type (2 bytes) free space (2 bytes) num of slots (2 bytes) freelist head(2 bytes) slot 0 (4 bytes) slot 1 (4 bytes) ... slot n (4 bytes) ... unused ... record n (x bytes) ... record 0 (y bytes) record 1 (z bytes) START $Id$ @todo slotted.c Should know that specific record types (like blobs) exist, (but should not hardcode information about these types) This has been handled, except in slottedPostRalloc... ************************************************************************/ #ifndef STASIS_PAGE_SLOTTED_H #define STASIS_PAGE_SLOTTED_H static inline int16_t* stasis_page_slotted_freespace_ptr(Page * p) { return stasis_page_int16_ptr_from_end((p), 1); } static inline int16_t* stasis_page_slotted_numslots_ptr(Page * p) { return stasis_page_int16_ptr_from_end(p, 2); } static inline int16_t* stasis_page_slotted_freelist_ptr(Page * p) { return stasis_page_int16_ptr_from_end(p, 3); } static inline int16_t* stasis_page_slotted_slot_ptr(Page * p, slotid_t n) { return stasis_page_int16_ptr_from_end(p, (2*(n))+4); } static inline int16_t* stasis_page_slotted_slot_length_ptr(Page * p, slotid_t n) { return stasis_page_int16_ptr_from_end((p), (2*(n))+5); } static inline byte* stasis_page_slotted_record_ptr(Page * p, slotid_t n) { return stasis_page_byte_ptr_from_start((p), *stasis_page_slotted_slot_ptr((p), (n))); } static inline const int16_t* stasis_page_slotted_freespace_cptr(const Page * p) { return stasis_page_slotted_freespace_ptr((Page*)p); } static inline const int16_t* stasis_page_slotted_numslots_cptr(const Page * p) { return stasis_page_slotted_numslots_ptr((Page*)p); } static inline const int16_t* stasis_page_slotted_freelist_cptr(const Page * p) { return stasis_page_slotted_freelist_ptr((Page*)p); } static inline const int16_t* stasis_page_slotted_slot_cptr(const Page * p, slotid_t n) { return stasis_page_slotted_slot_ptr((Page*)p, n); } static inline const int16_t* stasis_page_slotted_slot_length_cptr(const Page * p, slotid_t n) { return stasis_page_slotted_slot_length_ptr((Page*)p, n); } static inline const byte* stasis_page_slotted_record_cptr(const Page * p, slotid_t n) { return stasis_page_slotted_record_ptr((Page*)p, n); } void stasis_page_slotted_init(); void stasis_page_slotted_deinit(); page_impl stasis_page_slotted_impl(); page_impl stasis_page_boundary_tag_impl(); #endif //STASIS_PAGE_SLOTTED_H