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more TDB

This commit is contained in:
Hongze Cheng 2022-03-25 07:19:48 +00:00
parent cc176b1037
commit 07f6d03a52
1 changed files with 96 additions and 11 deletions
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107
source/libs/tdb/src/db/tdbBtree.c
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@ -131,15 +131,6 @@ int tdbBtreeClose(SBTree *pBt) {
return 0;
}
int tdbBtcOpen(SBTC *pCur, SBTree *pBt) {
pCur->pBt = pBt;
pCur->iPage = -1;
pCur->pPage = NULL;
pCur->idx = -1;
return 0;
}
int tdbBtCursorInsert(SBTC *pCur, const void *pKey, int kLen, const void *pVal, int vLen) {
int ret;
int idx;
@ -1073,13 +1064,107 @@ static int tdbBtreeCellSize(const SPage *pPage, SCell *pCell) {
#endif
int tdbBtcOpen(SBTC *pCur, SBTree *pBt) {
pCur->pBt = pBt;
pCur->iPage = -1;
pCur->pPage = NULL;
pCur->idx = -1;
return 0;
}
int tdbBtcMoveToFirst(SBTC *pBtc) {
// TODO
int ret;
SBTree *pBt;
SPager *pPager;
u8 flags;
SCell *pCell;
SPgno pgno;
pBt = pBtc->pBt;
pPager = pBt->pPager;
if (pBtc->iPage < 0) {
// move a clean cursor
ret = tdbPagerFetchPage(pPager, pBt->root, &(pBtc->pPage), tdbBtreeInitPage, pBt);
if (ret < 0) {
ASSERT(0);
return -1;
}
pBtc->iPage = 0;
pBtc->idx = 0;
} else {
// move from a position
ASSERT(0);
}
// move downward
for (;;) {
flags = TDB_BTREE_PAGE_GET_FLAGS(pBtc->pPage);
if (TDB_BTREE_PAGE_IS_LEAF(flags)) break;
pCell = tdbPageGetCell(pBtc->pPage, 0);
pgno = *(SPgno *)pCell;
ret = tdbBtCursorMoveToChild(pBtc, pgno);
if (ret < 0) {
ASSERT(0);
return -1;
}
pBtc->idx = 0;
}
return 0;
}
int tdbBtcMoveToLast(SBTC *pBtc) {
// TODO
int ret;
SBTree *pBt;
SPager *pPager;
u8 flags;
SPgno pgno;
pBt = pBtc->pBt;
pPager = pBt->pPager;
if (pBtc->iPage < 0) {
// move a clean cursor
ret = tdbPagerFetchPage(pPager, pBt->root, &(pBtc->pPage), tdbBtreeInitPage, pBt);
if (ret < 0) {
ASSERT(0);
return -1;
}
pBtc->iPage = 0;
} else {
// move from a position
ASSERT(0);
}
// move downward
for (;;) {
flags = TDB_BTREE_PAGE_GET_FLAGS(pBtc->pPage);
if (TDB_BTREE_PAGE_IS_LEAF(flags)) {
// TODO: handle empty case
ASSERT(TDB_PAGE_TOTAL_CELLS(pBtc->pPage) > 0);
pBtc->idx = TDB_PAGE_TOTAL_CELLS(pBtc->pPage) - 1;
break;
} else {
pBtc->idx = TDB_PAGE_TOTAL_CELLS(pBtc->pPage);
pgno = ((SIntHdr *)pBtc->pPage->pData)->pgno;
ret = tdbBtCursorMoveToChild(pBtc, pgno);
if (ret < 0) {
ASSERT(0);
return -1;
}
}
}
return 0;
}