diff options
Diffstat (limited to 'src/backend/access/nbtree/nbtsearch.c')
| -rw-r--r-- | src/backend/access/nbtree/nbtsearch.c | 80 |
1 files changed, 42 insertions, 38 deletions
diff --git a/src/backend/access/nbtree/nbtsearch.c b/src/backend/access/nbtree/nbtsearch.c index c1a82f2b856..2cfb8c8f001 100644 --- a/src/backend/access/nbtree/nbtsearch.c +++ b/src/backend/access/nbtree/nbtsearch.c @@ -8,7 +8,7 @@ * Portions Copyright (c) 1994, Regents of the University of California * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/backend/access/nbtree/nbtsearch.c,v 1.69 2001/10/25 05:49:21 momjian Exp $ + * $Header: /cvsroot/pgsql/src/backend/access/nbtree/nbtsearch.c,v 1.70 2002/05/20 23:51:41 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -19,7 +19,7 @@ #include "access/nbtree.h" -static RetrieveIndexResult _bt_endpoint(IndexScanDesc scan, ScanDirection dir); +static bool _bt_endpoint(IndexScanDesc scan, ScanDirection dir); /* @@ -357,11 +357,11 @@ _bt_compare(Relation rel, * * On entry, we have a valid currentItemData in the scan, and a * read lock and pin count on the page that contains that item. - * We return the next item in the scan, or NULL if no more. + * We return the next item in the scan, or false if no more. * On successful exit, the page containing the new item is locked - * and pinned; on NULL exit, no lock or pin is held. + * and pinned; on failure exit, no lock or pin is held. */ -RetrieveIndexResult +bool _bt_next(IndexScanDesc scan, ScanDirection dir) { Relation rel; @@ -374,7 +374,7 @@ _bt_next(IndexScanDesc scan, ScanDirection dir) BTScanOpaque so; bool continuescan; - rel = scan->relation; + rel = scan->indexRelation; so = (BTScanOpaque) scan->opaque; current = &(scan->currentItemData); @@ -386,7 +386,7 @@ _bt_next(IndexScanDesc scan, ScanDirection dir) { /* step one tuple in the appropriate direction */ if (!_bt_step(scan, &buf, dir)) - return (RetrieveIndexResult) NULL; + return false; /* current is the next candidate tuple to return */ offnum = ItemPointerGetOffsetNumber(current); @@ -397,7 +397,8 @@ _bt_next(IndexScanDesc scan, ScanDirection dir) if (_bt_checkkeys(scan, itup, dir, &continuescan)) { /* tuple passes all scan key conditions, so return it */ - return FormRetrieveIndexResult(current, &(itup->t_tid)); + scan->xs_ctup.t_self = itup->t_tid; + return true; } /* This tuple doesn't pass, but there might be more that do */ @@ -408,20 +409,20 @@ _bt_next(IndexScanDesc scan, ScanDirection dir) so->btso_curbuf = InvalidBuffer; _bt_relbuf(rel, buf); - return (RetrieveIndexResult) NULL; + return false; } /* * _bt_first() -- Find the first item in a scan. * * We need to be clever about the type of scan, the operation it's - * performing, and the tree ordering. We return the RetrieveIndexResult - * of the first item in the tree that satisfies the qualification + * performing, and the tree ordering. We find the + * first item in the tree that satisfies the qualification * associated with the scan descriptor. On exit, the page containing * the current index tuple is read locked and pinned, and the scan's * opaque data entry is updated to include the buffer. */ -RetrieveIndexResult +bool _bt_first(IndexScanDesc scan, ScanDirection dir) { Relation rel; @@ -434,9 +435,10 @@ _bt_first(IndexScanDesc scan, ScanDirection dir) ItemPointer current; BlockNumber blkno; StrategyNumber strat; - RetrieveIndexResult res; + bool res; int32 result; BTScanOpaque so; + bool scanFromEnd; bool continuescan; ScanKey scankeys = NULL; int keysCount = 0; @@ -445,7 +447,7 @@ _bt_first(IndexScanDesc scan, ScanDirection dir) j; StrategyNumber strat_total; - rel = scan->relation; + rel = scan->indexRelation; so = (BTScanOpaque) scan->opaque; /* @@ -459,12 +461,12 @@ _bt_first(IndexScanDesc scan, ScanDirection dir) * be satisfied (eg, x == 1 AND x > 2). */ if (!so->qual_ok) - return (RetrieveIndexResult) NULL; + return false; /* * Examine the scan keys to discover where we need to start the scan. */ - scan->scanFromEnd = false; + scanFromEnd = false; strat_total = BTEqualStrategyNumber; if (so->numberOfKeys > 0) { @@ -511,13 +513,13 @@ _bt_first(IndexScanDesc scan, ScanDirection dir) } } if (keysCount == 0) - scan->scanFromEnd = true; + scanFromEnd = true; } else - scan->scanFromEnd = true; + scanFromEnd = true; /* if we just need to walk down one edge of the tree, do that */ - if (scan->scanFromEnd) + if (scanFromEnd) { if (nKeyIs) pfree(nKeyIs); @@ -544,7 +546,7 @@ _bt_first(IndexScanDesc scan, ScanDirection dir) pfree(nKeyIs); pfree(scankeys); elog(ERROR, "_bt_first: btree doesn't support is(not)null, yet"); - return ((RetrieveIndexResult) NULL); + return false; } procinfo = index_getprocinfo(rel, i + 1, BTORDER_PROC); ScanKeyEntryInitializeWithInfo(scankeys + i, @@ -574,7 +576,7 @@ _bt_first(IndexScanDesc scan, ScanDirection dir) ItemPointerSetInvalid(current); so->btso_curbuf = InvalidBuffer; pfree(scankeys); - return (RetrieveIndexResult) NULL; + return false; } /* remember which buffer we have pinned */ @@ -598,7 +600,7 @@ _bt_first(IndexScanDesc scan, ScanDirection dir) * the scan strategy to find the exact place to start the scan. * * Note: if _bt_step fails (meaning we fell off the end of the index in - * one direction or the other), we either return NULL (no matches) or + * one direction or the other), we either return false (no matches) or * call _bt_endpoint() to set up a scan starting at that index * endpoint, as appropriate for the desired scan type. * @@ -615,7 +617,7 @@ _bt_first(IndexScanDesc scan, ScanDirection dir) if (!_bt_step(scan, &buf, BackwardScanDirection)) { pfree(scankeys); - return (RetrieveIndexResult) NULL; + return false; } break; @@ -649,7 +651,7 @@ _bt_first(IndexScanDesc scan, ScanDirection dir) if (!_bt_step(scan, &buf, BackwardScanDirection)) { pfree(scankeys); - return (RetrieveIndexResult) NULL; + return false; } break; @@ -664,7 +666,7 @@ _bt_first(IndexScanDesc scan, ScanDirection dir) if (!_bt_step(scan, &buf, ForwardScanDirection)) { pfree(scankeys); - return (RetrieveIndexResult) NULL; + return false; } offnum = ItemPointerGetOffsetNumber(current); page = BufferGetPage(buf); @@ -706,7 +708,7 @@ _bt_first(IndexScanDesc scan, ScanDirection dir) if (!_bt_step(scan, &buf, ForwardScanDirection)) { pfree(scankeys); - return (RetrieveIndexResult) NULL; + return false; } } break; @@ -722,7 +724,7 @@ _bt_first(IndexScanDesc scan, ScanDirection dir) if (!_bt_step(scan, &buf, ForwardScanDirection)) { pfree(scankeys); - return (RetrieveIndexResult) NULL; + return false; } offnum = ItemPointerGetOffsetNumber(current); page = BufferGetPage(buf); @@ -733,7 +735,7 @@ _bt_first(IndexScanDesc scan, ScanDirection dir) if (!_bt_step(scan, &buf, ForwardScanDirection)) { pfree(scankeys); - return (RetrieveIndexResult) NULL; + return false; } offnum = ItemPointerGetOffsetNumber(current); page = BufferGetPage(buf); @@ -752,7 +754,8 @@ _bt_first(IndexScanDesc scan, ScanDirection dir) if (_bt_checkkeys(scan, itup, dir, &continuescan)) { /* yes, return it */ - res = FormRetrieveIndexResult(current, &(itup->t_tid)); + scan->xs_ctup.t_self = itup->t_tid; + res = true; } else if (continuescan) { @@ -766,7 +769,7 @@ nomatches: ItemPointerSetInvalid(current); so->btso_curbuf = InvalidBuffer; _bt_relbuf(rel, buf); - res = (RetrieveIndexResult) NULL; + res = false; } pfree(scankeys); @@ -788,7 +791,7 @@ nomatches: bool _bt_step(IndexScanDesc scan, Buffer *bufP, ScanDirection dir) { - Relation rel = scan->relation; + Relation rel = scan->indexRelation; ItemPointer current = &(scan->currentItemData); BTScanOpaque so = (BTScanOpaque) scan->opaque; Page page; @@ -902,7 +905,7 @@ _bt_step(IndexScanDesc scan, Buffer *bufP, ScanDirection dir) * that the scan must start at the beginning or end of the index (for * a forward or backward scan respectively). */ -static RetrieveIndexResult +static bool _bt_endpoint(IndexScanDesc scan, ScanDirection dir) { Relation rel; @@ -917,10 +920,10 @@ _bt_endpoint(IndexScanDesc scan, ScanDirection dir) BTItem btitem; IndexTuple itup; BTScanOpaque so; - RetrieveIndexResult res; + bool res; bool continuescan; - rel = scan->relation; + rel = scan->indexRelation; current = &(scan->currentItemData); so = (BTScanOpaque) scan->opaque; @@ -936,7 +939,7 @@ _bt_endpoint(IndexScanDesc scan, ScanDirection dir) /* empty index... */ ItemPointerSetInvalid(current); so->btso_curbuf = InvalidBuffer; - return (RetrieveIndexResult) NULL; + return false; } blkno = BufferGetBlockNumber(buf); @@ -1016,7 +1019,7 @@ _bt_endpoint(IndexScanDesc scan, ScanDirection dir) if (start > maxoff) { if (!_bt_step(scan, &buf, dir)) - return (RetrieveIndexResult) NULL; + return false; start = ItemPointerGetOffsetNumber(current); page = BufferGetPage(buf); } @@ -1028,7 +1031,8 @@ _bt_endpoint(IndexScanDesc scan, ScanDirection dir) if (_bt_checkkeys(scan, itup, dir, &continuescan)) { /* yes, return it */ - res = FormRetrieveIndexResult(current, &(itup->t_tid)); + scan->xs_ctup.t_self = itup->t_tid; + res = true; } else if (continuescan) { @@ -1041,7 +1045,7 @@ _bt_endpoint(IndexScanDesc scan, ScanDirection dir) ItemPointerSetInvalid(current); so->btso_curbuf = InvalidBuffer; _bt_relbuf(rel, buf); - res = (RetrieveIndexResult) NULL; + res = false; } return res; |