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refact more

This commit is contained in:
Hongze Cheng 2022-03-31 06:22:29 +00:00
parent 839912e4f5
commit 59061a6fb5
1 changed files with 40 additions and 7 deletions
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47
source/libs/tdb/src/db/tdbBtree.c
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@ -1040,12 +1040,11 @@ int tdbBtcMoveToFirst(SBTC *pBtc) {
// move upward
for (;;) {
if (pBtc->iPage == 0) {
if (pBtc->iPage == iPage) {
pBtc->idx = 0;
break;
}
if (pBtc->iPage < iPage) break;
tdbBtcMoveUpward(pBtc);
}
}
@ -1106,15 +1105,15 @@ int tdbBtcMoveToLast(SBTC *pBtc) {
// move upward
for (;;) {
if (pBtc->iPage == 0) {
if (pBtc->iPage == iPage) {
if (TDB_BTREE_PAGE_IS_LEAF(pBtc->pPage)) {
pBtc->idx = TDB_PAGE_TOTAL_CELLS(pBtc->pPage) - 1;
} else {
pBtc->idx = TDB_PAGE_TOTAL_CELLS(pBtc->pPage);
}
break;
}
if (pBtc->iPage < iPage) break;
tdbBtcMoveUpward(pBtc);
}
}
@ -1275,6 +1274,8 @@ static int tdbBtcMoveUpward(SBTC *pBtc) {
static int tdbBtcMoveTo(SBTC *pBtc, const void *pKey, int kLen, int *pCRst) {
int ret;
int nCells;
int c;
SBTree *pBt;
SCell *pCell;
SPager *pPager;
@ -1297,13 +1298,45 @@ static int tdbBtcMoveTo(SBTC *pBtc, const void *pKey, int kLen, int *pCRst) {
// for empty tree, just return with an invalid position
if (TDB_PAGE_TOTAL_CELLS(pBtc->pPage) == 0) return 0;
} else {
// move upward to a page that the search key is in the range
ASSERT(0);
SPage *pPage;
int idx;
int iPage = 0;
// downward search
for (; iPage < pBtc->iPage; iPage++) {
pPage = pBtc->pgStack[iPage];
idx = pBtc->idxStack[iPage];
nCells = TDB_PAGE_TOTAL_CELLS(pPage);
ASSERT(!TDB_BTREE_PAGE_IS_LEAF(pPage));
// check if key <= current position
if (idx < nCells) {
pCell = tdbPageGetCell(pPage, idx);
tdbBtreeDecodeCell(pPage, pCell, &cd);
c = pBt->kcmpr(pKey, kLen, cd.pKey, cd.kLen);
if (c > 0) break;
}
// check if key > current - 1 position
if (idx > 0) {
pCell = tdbPageGetCell(pPage, idx - 1);
tdbBtreeDecodeCell(pPage, pCell, &cd);
c = pBt->kcmpr(pKey, kLen, cd.pKey, cd.kLen);
if (c <= 0) break;
}
}
// move upward
for (;;) {
if (pBtc->iPage == iPage) break;
tdbBtcMoveUpward(pBtc);
}
}
// search downward to the leaf
for (;;) {
int lidx, ridx, midx, c, nCells;
int lidx, ridx, midx;
SPage *pPage;
pPage = pBtc->pPage;