stasis-aries-wal/stasis/allocationPolicy.h

#ifndef ALLOCATION_POLICY_H
#define ALLOCATION_POLICY_H

#include <stasis/common.h>

struct stasis_allocation_policy_t;
typedef struct stasis_allocation_policy_t stasis_allocation_policy_t;

stasis_allocation_policy_t * stasis_allocation_policy_init();
void stasis_allocation_policy_deinit(stasis_allocation_policy_t * ap);
void stasis_allocation_policy_register_new_page(stasis_allocation_policy_t * ap, pageid_t page, size_t freespace); //availablePage** newPages);
pageid_t stasis_allocation_policy_pick_suitable_page(stasis_allocation_policy_t * ap, int xid, size_t freespace);
void stasis_allocation_policy_transaction_completed(stasis_allocation_policy_t * ap, int xid);
void stasis_allocation_policy_update_freespace(stasis_allocation_policy_t * ap, pageid_t pageid, size_t freespace);
void stasis_allocation_policy_dealloced_from_page(stasis_allocation_policy_t * ap, int xid, pageid_t page);
void stasis_allocation_policy_alloced_from_page(stasis_allocation_policy_t * ap, int xid, pageid_t page);
/**
   Check to see if it is safe to allocate from a particular page.

   If concurrent transactions have freed up space on a page, but they
   eventually abort, then it might not be safe for the current
   transaction to reuse the storage those transactions freed.  This is
   needed for methods such as TallocFromPage(), which do not consult
   allocation policy before deciding where to attempt allocation.

   @param ap The allocation policy managing the space in question
   @param xid The transaction that wants to allocate space from the page
   @param page The page that will be allocated from.
   @return true if the allocation would be safe.  false if not sure.
 */
int stasis_allocation_policy_can_xid_alloc_from_page(stasis_allocation_policy_t * ap, int xid, pageid_t page);
#endif // ALLOCATION_POLICY_H