diff options
Diffstat (limited to 'src/backend/storage/page/bufpage.c')
| -rw-r--r-- | src/backend/storage/page/bufpage.c | 26 |
1 files changed, 23 insertions, 3 deletions
diff --git a/src/backend/storage/page/bufpage.c b/src/backend/storage/page/bufpage.c index 2e5c7c412bf..8299f550d6e 100644 --- a/src/backend/storage/page/bufpage.c +++ b/src/backend/storage/page/bufpage.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/storage/page/bufpage.c,v 1.70 2007/01/05 22:19:38 momjian Exp $ + * $PostgreSQL: pgsql/src/backend/storage/page/bufpage.c,v 1.71 2007/02/21 20:02:17 momjian Exp $ * *------------------------------------------------------------------------- */ @@ -418,7 +418,8 @@ PageRepairFragmentation(Page page, OffsetNumber *unused) /* * PageGetFreeSpace - * Returns the size of the free (allocatable) space on a page. + * Returns the size of the free (allocatable) space on a page, + * deducted by the space needed for a new line pointer. */ Size PageGetFreeSpace(Page page) @@ -434,7 +435,26 @@ PageGetFreeSpace(Page page) if (space < (int) sizeof(ItemIdData)) return 0; - space -= sizeof(ItemIdData); /* XXX not always appropriate */ + space -= sizeof(ItemIdData); + + return (Size) space; +} + +/* + * PageGetExactFreeSpace + * Returns the size of the free (allocatable) space on a page. + */ +Size +PageGetExactFreeSpace(Page page) +{ + int space; + + /* + * Use signed arithmetic here so that we behave sensibly if pd_lower > + * pd_upper. + */ + space = (int) ((PageHeader) page)->pd_upper - + (int) ((PageHeader) page)->pd_lower; return (Size) space; } |