GIF89a;
EcchiShell v1.0
/
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proc/
self/
root/
usr/
include/
pgsql/
pd_lower <= SizeOfPageHeaderData)
/*
* PageIsNew
* returns true iff page has not been initialized (by PageInit)
*/
#define PageIsNew(page) (((PageHeader) (page))->pd_upper == 0)
/*
* PageGetItemId
* Returns an item identifier of a page.
*/
#define PageGetItemId(page, offsetNumber) \
((ItemId) (&((PageHeader) (page))->pd_linp[(offsetNumber) - 1]))
/*
* PageGetContents
* To be used in case the page does not contain item pointers.
*
* Note: prior to 8.3 this was not guaranteed to yield a MAXALIGN'd result.
* Now it is. Beware of old code that might think the offset to the contents
* is just SizeOfPageHeaderData rather than MAXALIGN(SizeOfPageHeaderData).
*/
#define PageGetContents(page) \
((char *) (page) + MAXALIGN(SizeOfPageHeaderData))
/* ----------------
* macros to access page size info
* ----------------
*/
/*
* PageSizeIsValid
* True iff the page size is valid.
*/
#define PageSizeIsValid(pageSize) ((pageSize) == BLCKSZ)
/*
* PageGetPageSize
* Returns the page size of a page.
*
* this can only be called on a formatted page (unlike
* BufferGetPageSize, which can be called on an unformatted page).
* however, it can be called on a page that is not stored in a buffer.
*/
#define PageGetPageSize(page) \
((Size) (((PageHeader) (page))->pd_pagesize_version & (uint16) 0xFF00))
/*
* PageGetPageLayoutVersion
* Returns the page layout version of a page.
*/
#define PageGetPageLayoutVersion(page) \
(((PageHeader) (page))->pd_pagesize_version & 0x00FF)
/*
* PageSetPageSizeAndVersion
* Sets the page size and page layout version number of a page.
*
* We could support setting these two values separately, but there's
* no real need for it at the moment.
*/
#define PageSetPageSizeAndVersion(page, size, version) \
( \
AssertMacro(((size) & 0xFF00) == (size)), \
AssertMacro(((version) & 0x00FF) == (version)), \
((PageHeader) (page))->pd_pagesize_version = (size) | (version) \
)
/* ----------------
* page special data macros
* ----------------
*/
/*
* PageGetSpecialSize
* Returns size of special space on a page.
*/
#define PageGetSpecialSize(page) \
((uint16) (PageGetPageSize(page) - ((PageHeader)(page))->pd_special))
/*
* PageGetSpecialPointer
* Returns pointer to special space on a page.
*/
#define PageGetSpecialPointer(page) \
( \
AssertMacro(PageIsValid(page)), \
(char *) ((char *) (page) + ((PageHeader) (page))->pd_special) \
)
/*
* PageGetItem
* Retrieves an item on the given page.
*
* Note:
* This does not change the status of any of the resources passed.
* The semantics may change in the future.
*/
#define PageGetItem(page, itemId) \
( \
AssertMacro(PageIsValid(page)), \
AssertMacro(ItemIdHasStorage(itemId)), \
(Item)(((char *)(page)) + ItemIdGetOffset(itemId)) \
)
/*
* PageGetMaxOffsetNumber
* Returns the maximum offset number used by the given page.
* Since offset numbers are 1-based, this is also the number
* of items on the page.
*
* NOTE: if the page is not initialized (pd_lower == 0), we must
* return zero to ensure sane behavior. Accept double evaluation
* of the argument so that we can ensure this.
*/
#define PageGetMaxOffsetNumber(page) \
(((PageHeader) (page))->pd_lower <= SizeOfPageHeaderData ? 0 : \
((((PageHeader) (page))->pd_lower - SizeOfPageHeaderData) \
/ sizeof(ItemIdData)))
/*
* Additional macros for access to page headers
*/
#define PageGetLSN(page) \
(((PageHeader) (page))->pd_lsn)
#define PageSetLSN(page, lsn) \
(((PageHeader) (page))->pd_lsn = (lsn))
/* NOTE: only the 16 least significant bits are stored */
#define PageGetTLI(page) \
(((PageHeader) (page))->pd_tli)
#define PageSetTLI(page, tli) \
(((PageHeader) (page))->pd_tli = (uint16) (tli))
#define PageHasFreeLinePointers(page) \
(((PageHeader) (page))->pd_flags & PD_HAS_FREE_LINES)
#define PageSetHasFreeLinePointers(page) \
(((PageHeader) (page))->pd_flags |= PD_HAS_FREE_LINES)
#define PageClearHasFreeLinePointers(page) \
(((PageHeader) (page))->pd_flags &= ~PD_HAS_FREE_LINES)
#define PageIsFull(page) \
(((PageHeader) (page))->pd_flags & PD_PAGE_FULL)
#define PageSetFull(page) \
(((PageHeader) (page))->pd_flags |= PD_PAGE_FULL)
#define PageClearFull(page) \
(((PageHeader) (page))->pd_flags &= ~PD_PAGE_FULL)
#define PageIsAllVisible(page) \
(((PageHeader) (page))->pd_flags & PD_ALL_VISIBLE)
#define PageSetAllVisible(page) \
(((PageHeader) (page))->pd_flags |= PD_ALL_VISIBLE)
#define PageClearAllVisible(page) \
(((PageHeader) (page))->pd_flags &= ~PD_ALL_VISIBLE)
#define PageIsPrunable(page, oldestxmin) \
( \
AssertMacro(TransactionIdIsNormal(oldestxmin)), \
TransactionIdIsValid(((PageHeader) (page))->pd_prune_xid) && \
TransactionIdPrecedes(((PageHeader) (page))->pd_prune_xid, oldestxmin) \
)
#define PageSetPrunable(page, xid) \
do { \
Assert(TransactionIdIsNormal(xid)); \
if (!TransactionIdIsValid(((PageHeader) (page))->pd_prune_xid) || \
TransactionIdPrecedes(xid, ((PageHeader) (page))->pd_prune_xid)) \
((PageHeader) (page))->pd_prune_xid = (xid); \
} while (0)
#define PageClearPrunable(page) \
(((PageHeader) (page))->pd_prune_xid = InvalidTransactionId)
/* ----------------------------------------------------------------
* extern declarations
* ----------------------------------------------------------------
*/
extern void PageInit(Page page, Size pageSize, Size specialSize);
extern bool PageHeaderIsValid(PageHeader page);
extern OffsetNumber PageAddItem(Page page, Item item, Size size,
OffsetNumber offsetNumber, bool overwrite, bool is_heap);
extern Page PageGetTempPage(Page page);
extern Page PageGetTempPageCopy(Page page);
extern Page PageGetTempPageCopySpecial(Page page);
extern void PageRestoreTempPage(Page tempPage, Page oldPage);
extern void PageRepairFragmentation(Page page);
extern Size PageGetFreeSpace(Page page);
extern Size PageGetExactFreeSpace(Page page);
extern Size PageGetHeapFreeSpace(Page page);
extern void PageIndexTupleDelete(Page page, OffsetNumber offset);
extern void PageIndexMultiDelete(Page page, OffsetNumber *itemnos, int nitems);
#endif /* BUFPAGE_H */