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refact

This commit is contained in:
Hongze Cheng 2022-03-30 06:58:56 +00:00
parent 953d325ac3
commit 3c78e4b7bf
1 changed files with 101 additions and 99 deletions
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200
source/libs/tdb/src/db/tdbBtree.c
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@ -256,105 +256,6 @@ int tdbBtreePGet(SBTree *pBt, const void *pKey, int kLen, void **ppKey, int *pkL
return 0;
}
static int tdbBtCursorMoveTo(SBTC *pBtc, const void *pKey, int kLen, int *pCRst) {
int ret;
SBTree *pBt;
SPager *pPager;
pBt = pBtc->pBt;
pPager = pBt->pPager;
if (pBtc->iPage < 0) {
ASSERT(pBtc->iPage == -1);
ASSERT(pBtc->idx == -1);
// Move from the root
ret = tdbPagerFetchPage(pPager, pBt->root, &(pBtc->pPage), tdbBtreeInitPage, pBt);
if (ret < 0) {
ASSERT(0);
return -1;
}
pBtc->iPage = 0;
if (TDB_PAGE_TOTAL_CELLS(pBtc->pPage) == 0) {
// Current page is empty
// ASSERT(TDB_FLAG_IS(TDB_PAGE_FLAGS(pBtc->pPage), TDB_BTREE_ROOT | TDB_BTREE_LEAF));
return 0;
}
for (;;) {
int lidx, ridx, midx, c, nCells;
SCell *pCell;
SPage *pPage;
SCellDecoder cd = {0};
pPage = pBtc->pPage;
nCells = TDB_PAGE_TOTAL_CELLS(pPage);
lidx = 0;
ridx = nCells - 1;
ASSERT(nCells > 0);
for (;;) {
if (lidx > ridx) break;
midx = (lidx + ridx) >> 1;
pCell = tdbPageGetCell(pPage, midx);
ret = tdbBtreeDecodeCell(pPage, pCell, &cd);
if (ret < 0) {
// TODO: handle error
ASSERT(0);
return -1;
}
// Compare the key values
c = pBt->kcmpr(pKey, kLen, cd.pKey, cd.kLen);
if (c < 0) {
/* input-key < cell-key */
ridx = midx - 1;
} else if (c > 0) {
/* input-key > cell-key */
lidx = midx + 1;
} else {
/* input-key == cell-key */
break;
}
}
// Move downward or break
u8 leaf = TDB_BTREE_PAGE_IS_LEAF(pPage);
if (leaf) {
pBtc->idx = midx;
*pCRst = c;
break;
} else {
if (c <= 0) {
pBtc->idx = midx;
tdbBtcMoveDownward(pBtc, cd.pgno);
} else {
pBtc->idx = midx + 1;
if (midx == nCells - 1) {
/* Move to right-most child */
tdbBtcMoveDownward(pBtc, ((SIntHdr *)pBtc->pPage->pData)->pgno);
} else {
pCell = tdbPageGetCell(pPage, pBtc->idx);
tdbBtreeDecodeCell(pPage, pCell, &cd);
tdbBtcMoveDownward(pBtc, cd.pgno);
}
}
}
}
} else {
// TODO: Move the cursor from a some position instead of a clear state
ASSERT(0);
}
return 0;
}
static int tdbDefaultKeyCmprFn(const void *pKey1, int keyLen1, const void *pKey2, int keyLen2) {
int mlen;
int cret;
@ -1077,6 +978,7 @@ static int tdbBtreeCellSize(const SPage *pPage, SCell *pCell) {
}
// TDB_BTREE_CELL
// TDB_BTREE_CURSOR =====================
int tdbBtcOpen(SBTC *pBtc, SBTree *pBt) {
pBtc->pBt = pBt;
pBtc->iPage = -1;
@ -1086,6 +988,105 @@ int tdbBtcOpen(SBTC *pBtc, SBTree *pBt) {
return 0;
}
static int tdbBtCursorMoveTo(SBTC *pBtc, const void *pKey, int kLen, int *pCRst) {
int ret;
SBTree *pBt;
SPager *pPager;
pBt = pBtc->pBt;
pPager = pBt->pPager;
if (pBtc->iPage < 0) {
ASSERT(pBtc->iPage == -1);
ASSERT(pBtc->idx == -1);
// Move from the root
ret = tdbPagerFetchPage(pPager, pBt->root, &(pBtc->pPage), tdbBtreeInitPage, pBt);
if (ret < 0) {
ASSERT(0);
return -1;
}
pBtc->iPage = 0;
if (TDB_PAGE_TOTAL_CELLS(pBtc->pPage) == 0) {
// Current page is empty
// ASSERT(TDB_FLAG_IS(TDB_PAGE_FLAGS(pBtc->pPage), TDB_BTREE_ROOT | TDB_BTREE_LEAF));
return 0;
}
for (;;) {
int lidx, ridx, midx, c, nCells;
SCell *pCell;
SPage *pPage;
SCellDecoder cd = {0};
pPage = pBtc->pPage;
nCells = TDB_PAGE_TOTAL_CELLS(pPage);
lidx = 0;
ridx = nCells - 1;
ASSERT(nCells > 0);
for (;;) {
if (lidx > ridx) break;
midx = (lidx + ridx) >> 1;
pCell = tdbPageGetCell(pPage, midx);
ret = tdbBtreeDecodeCell(pPage, pCell, &cd);
if (ret < 0) {
// TODO: handle error
ASSERT(0);
return -1;
}
// Compare the key values
c = pBt->kcmpr(pKey, kLen, cd.pKey, cd.kLen);
if (c < 0) {
/* input-key < cell-key */
ridx = midx - 1;
} else if (c > 0) {
/* input-key > cell-key */
lidx = midx + 1;
} else {
/* input-key == cell-key */
break;
}
}
// Move downward or break
u8 leaf = TDB_BTREE_PAGE_IS_LEAF(pPage);
if (leaf) {
pBtc->idx = midx;
*pCRst = c;
break;
} else {
if (c <= 0) {
pBtc->idx = midx;
tdbBtcMoveDownward(pBtc, cd.pgno);
} else {
pBtc->idx = midx + 1;
if (midx == nCells - 1) {
/* Move to right-most child */
tdbBtcMoveDownward(pBtc, ((SIntHdr *)pBtc->pPage->pData)->pgno);
} else {
pCell = tdbPageGetCell(pPage, pBtc->idx);
tdbBtreeDecodeCell(pPage, pCell, &cd);
tdbBtcMoveDownward(pBtc, cd.pgno);
}
}
}
}
} else {
// TODO: Move the cursor from a some position instead of a clear state
ASSERT(0);
}
return 0;
}
int tdbBtcMoveToFirst(SBTC *pBtc) {
int ret;
SBTree *pBt;
@ -1309,6 +1310,7 @@ static int tdbBtcMoveUpward(SBTC *pBtc) {
return 0;
}
// TDB_BTREE_CURSOR
#ifndef NODEBUG
typedef struct {