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pgindent run.

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This commit is contained in:
Bruce Momjian
2003-08-04 00:43:34 +00:00
parent 63354a0228
commit 089003fb46
554 changed files with 24888 additions and 21245 deletions
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149
src/backend/access/nbtree/nbtpage.c
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@@ -9,7 +9,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/access/nbtree/nbtpage.c,v 1.66 2003/07/21 20:29:39 tgl Exp $
* $Header: /cvsroot/pgsql/src/backend/access/nbtree/nbtpage.c,v 1.67 2003/08/04 00:43:15 momjian Exp $
*
* NOTES
* Postgres btree pages look like ordinary relation pages. The opaque
@@ -181,8 +181,8 @@ _bt_getroot(Relation rel, int access)
/*
* Metadata initialized by someone else. In order to
* guarantee no deadlocks, we have to release the metadata
* page and start all over again. (Is that really true?
* But it's hardly worth trying to optimize this case.)
* page and start all over again. (Is that really true? But
* it's hardly worth trying to optimize this case.)
*/
_bt_relbuf(rel, metabuf);
return _bt_getroot(rel, access);
@@ -190,8 +190,8 @@ _bt_getroot(Relation rel, int access)
/*
* Get, initialize, write, and leave a lock of the appropriate
* type on the new root page. Since this is the first page in
* the tree, it's a leaf as well as the root.
* type on the new root page. Since this is the first page in the
* tree, it's a leaf as well as the root.
*/
rootbuf = _bt_getbuf(rel, P_NEW, BT_WRITE);
rootblkno = BufferGetBlockNumber(rootbuf);
@@ -240,7 +240,7 @@ _bt_getroot(Relation rel, int access)
_bt_wrtnorelbuf(rel, rootbuf);
/*
* swap root write lock for read lock. There is no danger of
* swap root write lock for read lock. There is no danger of
* anyone else accessing the new root page while it's unlocked,
* since no one else knows where it is yet.
*/
@@ -284,8 +284,8 @@ _bt_getroot(Relation rel, int access)
}
/*
* By here, we have a pin and read lock on the root page, and no
* lock set on the metadata page. Return the root page's buffer.
* By here, we have a pin and read lock on the root page, and no lock
* set on the metadata page. Return the root page's buffer.
*/
return rootbuf;
}
@@ -299,7 +299,7 @@ _bt_getroot(Relation rel, int access)
* By the time we acquire lock on the root page, it might have been split and
* not be the true root anymore. This is okay for the present uses of this
* routine; we only really need to be able to move up at least one tree level
* from whatever non-root page we were at. If we ever do need to lock the
* from whatever non-root page we were at. If we ever do need to lock the
* one true root page, we could loop here, re-reading the metapage on each
* failure. (Note that it wouldn't do to hold the lock on the metapage while
* moving to the root --- that'd deadlock against any concurrent root split.)
@@ -406,9 +406,9 @@ _bt_getbuf(Relation rel, BlockNumber blkno, int access)
* First see if the FSM knows of any free pages.
*
* We can't trust the FSM's report unreservedly; we have to check
* that the page is still free. (For example, an already-free page
* could have been re-used between the time the last VACUUM scanned
* it and the time the VACUUM made its FSM updates.)
* that the page is still free. (For example, an already-free
* page could have been re-used between the time the last VACUUM
* scanned it and the time the VACUUM made its FSM updates.)
*/
for (;;)
{
@@ -431,10 +431,10 @@ _bt_getbuf(Relation rel, BlockNumber blkno, int access)
/*
* Extend the relation by one page.
*
* We have to use a lock to ensure no one else is extending the rel at
* the same time, else we will both try to initialize the same new
* page. We can skip locking for new or temp relations, however,
* since no one else could be accessing them.
* We have to use a lock to ensure no one else is extending the rel
* at the same time, else we will both try to initialize the same
* new page. We can skip locking for new or temp relations,
* however, since no one else could be accessing them.
*/
needLock = !(rel->rd_isnew || rel->rd_istemp);
@@ -444,8 +444,8 @@ _bt_getbuf(Relation rel, BlockNumber blkno, int access)
buf = ReadBuffer(rel, P_NEW);
/*
* Release the file-extension lock; it's now OK for someone else to
* extend the relation some more.
* Release the file-extension lock; it's now OK for someone else
* to extend the relation some more.
*/
if (needLock)
UnlockPage(rel, 0, ExclusiveLock);
@@ -484,7 +484,7 @@ _bt_relbuf(Relation rel, Buffer buf)
* and a pin on the buffer.
*
* NOTE: actually, the buffer manager just marks the shared buffer page
* dirty here; the real I/O happens later. This is okay since we are not
* dirty here; the real I/O happens later. This is okay since we are not
* relying on write ordering anyway. The WAL mechanism is responsible for
* guaranteeing correctness after a crash.
*/
@@ -534,13 +534,14 @@ _bt_page_recyclable(Page page)
BTPageOpaque opaque;
/*
* It's possible to find an all-zeroes page in an index --- for example,
* a backend might successfully extend the relation one page and then
* crash before it is able to make a WAL entry for adding the page.
* If we find a zeroed page then reclaim it.
* It's possible to find an all-zeroes page in an index --- for
* example, a backend might successfully extend the relation one page
* and then crash before it is able to make a WAL entry for adding the
* page. If we find a zeroed page then reclaim it.
*/
if (PageIsNew(page))
return true;
/*
* Otherwise, recycle if deleted and too old to have any processes
* interested in it.
@@ -565,7 +566,7 @@ _bt_page_recyclable(Page page)
* mistake. On exit, metapage data is correct and we no longer have
* a pin or lock on the metapage.
*
* Actually this is not used for splitting on-the-fly anymore. It's only used
* Actually this is not used for splitting on-the-fly anymore. It's only used
* in nbtsort.c at the completion of btree building, where we know we have
* sole access to the index anyway.
*/
@@ -623,7 +624,7 @@ _bt_metaproot(Relation rel, BlockNumber rootbknum, uint32 level)
/*
* Delete item(s) from a btree page.
*
* This must only be used for deleting leaf items. Deleting an item on a
* This must only be used for deleting leaf items. Deleting an item on a
* non-leaf page has to be done as part of an atomic action that includes
* deleting the page it points to.
*
@@ -646,9 +647,7 @@ _bt_delitems(Relation rel, Buffer buf,
* adjusting item numbers for previous deletions.
*/
for (i = nitems - 1; i >= 0; i--)
{
PageIndexTupleDelete(page, itemnos[i]);
}
/* XLOG stuff */
if (!rel->rd_istemp)
@@ -666,8 +665,8 @@ _bt_delitems(Relation rel, Buffer buf,
rdata[0].next = &(rdata[1]);
/*
* The target-offsets array is not in the buffer, but pretend
* that it is. When XLogInsert stores the whole buffer, the offsets
* The target-offsets array is not in the buffer, but pretend that
* it is. When XLogInsert stores the whole buffer, the offsets
* array need not be stored too.
*/
rdata[1].buffer = buf;
@@ -701,7 +700,7 @@ _bt_delitems(Relation rel, Buffer buf,
* may currently be trying to follow links leading to the page; they have to
* be allowed to use its right-link to recover. See nbtree/README.
*
* On entry, the target buffer must be pinned and read-locked. This lock and
* On entry, the target buffer must be pinned and read-locked. This lock and
* pin will be dropped before exiting.
*
* Returns the number of pages successfully deleted (zero on failure; could
@@ -714,7 +713,7 @@ _bt_delitems(Relation rel, Buffer buf,
int
_bt_pagedel(Relation rel, Buffer buf, bool vacuum_full)
{
BlockNumber target,
BlockNumber target,
leftsib,
rightsib,
parent;
@@ -740,17 +739,18 @@ _bt_pagedel(Relation rel, Buffer buf, bool vacuum_full)
BTPageOpaque opaque;
/*
* We can never delete rightmost pages nor root pages. While at it,
* We can never delete rightmost pages nor root pages. While at it,
* check that page is not already deleted and is empty.
*/
page = BufferGetPage(buf);
opaque = (BTPageOpaque) PageGetSpecialPointer(page);
if (P_RIGHTMOST(opaque) || P_ISROOT(opaque) || P_ISDELETED(opaque) ||
P_FIRSTDATAKEY(opaque) <= PageGetMaxOffsetNumber(page))
P_FIRSTDATAKEY(opaque) <= PageGetMaxOffsetNumber(page))
{
_bt_relbuf(rel, buf);
return 0;
}
/*
* Save info about page, including a copy of its high key (it must
* have one, being non-rightmost).
@@ -760,12 +760,13 @@ _bt_pagedel(Relation rel, Buffer buf, bool vacuum_full)
leftsib = opaque->btpo_prev;
itemid = PageGetItemId(page, P_HIKEY);
targetkey = CopyBTItem((BTItem) PageGetItem(page, itemid));
/*
* We need to get an approximate pointer to the page's parent page.
* Use the standard search mechanism to search for the page's high key;
* this will give us a link to either the current parent or someplace
* to its left (if there are multiple equal high keys). To avoid
* deadlocks, we'd better drop the target page lock first.
* Use the standard search mechanism to search for the page's high
* key; this will give us a link to either the current parent or
* someplace to its left (if there are multiple equal high keys). To
* avoid deadlocks, we'd better drop the target page lock first.
*/
_bt_relbuf(rel, buf);
/* we need a scan key to do our search, so build one */
@@ -775,9 +776,11 @@ _bt_pagedel(Relation rel, Buffer buf, bool vacuum_full)
&lbuf, BT_READ);
/* don't need a pin on that either */
_bt_relbuf(rel, lbuf);
/*
* If we are trying to delete an interior page, _bt_search did more
* than we needed. Locate the stack item pointing to our parent level.
* than we needed. Locate the stack item pointing to our parent
* level.
*/
ilevel = 0;
for (;;)
@@ -789,10 +792,12 @@ _bt_pagedel(Relation rel, Buffer buf, bool vacuum_full)
stack = stack->bts_parent;
ilevel++;
}
/*
* We have to lock the pages we need to modify in the standard order:
* moving right, then up. Else we will deadlock against other writers.
*
* moving right, then up. Else we will deadlock against other
* writers.
*
* So, we need to find and write-lock the current left sibling of the
* target page. The sibling that was current a moment ago could have
* split, so we may have to move right. This search could fail if
@@ -823,21 +828,24 @@ _bt_pagedel(Relation rel, Buffer buf, bool vacuum_full)
}
else
lbuf = InvalidBuffer;
/*
* Next write-lock the target page itself. It should be okay to take just
* a write lock not a superexclusive lock, since no scans would stop on an
* empty page.
* Next write-lock the target page itself. It should be okay to take
* just a write lock not a superexclusive lock, since no scans would
* stop on an empty page.
*/
buf = _bt_getbuf(rel, target, BT_WRITE);
page = BufferGetPage(buf);
opaque = (BTPageOpaque) PageGetSpecialPointer(page);
/*
* Check page is still empty etc, else abandon deletion. The empty check
* is necessary since someone else might have inserted into it while
* we didn't have it locked; the others are just for paranoia's sake.
* Check page is still empty etc, else abandon deletion. The empty
* check is necessary since someone else might have inserted into it
* while we didn't have it locked; the others are just for paranoia's
* sake.
*/
if (P_RIGHTMOST(opaque) || P_ISROOT(opaque) || P_ISDELETED(opaque) ||
P_FIRSTDATAKEY(opaque) <= PageGetMaxOffsetNumber(page))
P_FIRSTDATAKEY(opaque) <= PageGetMaxOffsetNumber(page))
{
_bt_relbuf(rel, buf);
if (BufferIsValid(lbuf))
@@ -846,14 +854,17 @@ _bt_pagedel(Relation rel, Buffer buf, bool vacuum_full)
}
if (opaque->btpo_prev != leftsib)
elog(ERROR, "left link changed unexpectedly");
/*
* And next write-lock the (current) right sibling.
*/
rightsib = opaque->btpo_next;
rbuf = _bt_getbuf(rel, rightsib, BT_WRITE);
/*
* Next find and write-lock the current parent of the target page.
* This is essentially the same as the corresponding step of splitting.
* This is essentially the same as the corresponding step of
* splitting.
*/
ItemPointerSet(&(stack->bts_btitem.bti_itup.t_tid),
target, P_HIKEY);
@@ -863,10 +874,11 @@ _bt_pagedel(Relation rel, Buffer buf, bool vacuum_full)
RelationGetRelationName(rel));
parent = stack->bts_blkno;
poffset = stack->bts_offset;
/*
* If the target is the rightmost child of its parent, then we can't
* delete, unless it's also the only child --- in which case the parent
* changes to half-dead status.
* delete, unless it's also the only child --- in which case the
* parent changes to half-dead status.
*/
page = BufferGetPage(pbuf);
opaque = (BTPageOpaque) PageGetSpecialPointer(page);
@@ -893,12 +905,13 @@ _bt_pagedel(Relation rel, Buffer buf, bool vacuum_full)
if (OffsetNumberNext(P_FIRSTDATAKEY(opaque)) == maxoff)
parent_one_child = true;
}
/*
* If we are deleting the next-to-last page on the target's level,
* then the rightsib is a candidate to become the new fast root.
* (In theory, it might be possible to push the fast root even further
* down, but the odds of doing so are slim, and the locking considerations
* daunting.)
* then the rightsib is a candidate to become the new fast root. (In
* theory, it might be possible to push the fast root even further
* down, but the odds of doing so are slim, and the locking
* considerations daunting.)
*
* We can safely acquire a lock on the metapage here --- see comments for
* _bt_newroot().
@@ -914,12 +927,13 @@ _bt_pagedel(Relation rel, Buffer buf, bool vacuum_full)
metabuf = _bt_getbuf(rel, BTREE_METAPAGE, BT_WRITE);
metapg = BufferGetPage(metabuf);
metad = BTPageGetMeta(metapg);
/*
* The expected case here is btm_fastlevel == targetlevel+1;
* if the fastlevel is <= targetlevel, something is wrong, and we
* choose to overwrite it to fix it.
* if the fastlevel is <= targetlevel, something is wrong, and
* we choose to overwrite it to fix it.
*/
if (metad->btm_fastlevel > targetlevel+1)
if (metad->btm_fastlevel > targetlevel + 1)
{
/* no update wanted */
_bt_relbuf(rel, metabuf);
@@ -937,9 +951,9 @@ _bt_pagedel(Relation rel, Buffer buf, bool vacuum_full)
/*
* Update parent. The normal case is a tad tricky because we want to
* delete the target's downlink and the *following* key. Easiest way is
* to copy the right sibling's downlink over the target downlink, and then
* delete the following item.
* delete the target's downlink and the *following* key. Easiest way
* is to copy the right sibling's downlink over the target downlink,
* and then delete the following item.
*/
page = BufferGetPage(pbuf);
opaque = (BTPageOpaque) PageGetSpecialPointer(page);
@@ -950,7 +964,7 @@ _bt_pagedel(Relation rel, Buffer buf, bool vacuum_full)
}
else
{
OffsetNumber nextoffset;
OffsetNumber nextoffset;
itemid = PageGetItemId(page, poffset);
btitem = (BTItem) PageGetItem(page, itemid);
@@ -968,8 +982,8 @@ _bt_pagedel(Relation rel, Buffer buf, bool vacuum_full)
}
/*
* Update siblings' side-links. Note the target page's side-links will
* continue to point to the siblings.
* Update siblings' side-links. Note the target page's side-links
* will continue to point to the siblings.
*/
if (BufferIsValid(lbuf))
{
@@ -1096,10 +1110,11 @@ _bt_pagedel(Relation rel, Buffer buf, bool vacuum_full)
_bt_wrtbuf(rel, lbuf);
/*
* If parent became half dead, recurse to try to delete it. Otherwise,
* if right sibling is empty and is now the last child of the parent,
* recurse to try to delete it. (These cases cannot apply at the same
* time, though the second case might itself recurse to the first.)
* If parent became half dead, recurse to try to delete it.
* Otherwise, if right sibling is empty and is now the last child of
* the parent, recurse to try to delete it. (These cases cannot apply
* at the same time, though the second case might itself recurse to
* the first.)
*/
if (parent_half_dead)
{