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more TDB

This commit is contained in:
Hongze Cheng 2022-03-16 10:19:37 +00:00
parent 16e7fa2e9e
commit 0c02e1123d
1 changed files with 33 additions and 8 deletions
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41
source/libs/tdb/src/db/tdbBtree.c
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@ -380,11 +380,13 @@ static int tdbBtreeOpenImpl(SBTree *pBt) {
static int tdbBtreeInitPage(SPage *pPage, void *arg) { static int tdbBtreeInitPage(SPage *pPage, void *arg) {
SBTree *pBt; SBTree *pBt;
u16 flags; u16 flags;
u8 isLeaf;
pBt = (SBTree *)arg; pBt = (SBTree *)arg;
flags = TDB_PAGE_FLAGS(pPage); flags = TDB_PAGE_FLAGS(pPage);
if (TDB_BTREE_PAGE_IS_LEAF(flags)) { isLeaf = TDB_BTREE_PAGE_IS_LEAF(flags);
if (isLeaf) {
pPage->szAmHdr = 0; pPage->szAmHdr = 0;
} else { } else {
pPage->szAmHdr = sizeof(SBtPageHdr); pPage->szAmHdr = sizeof(SBtPageHdr);
@ -399,7 +401,7 @@ static int tdbBtreeInitPage(SPage *pPage, void *arg) {
TDB_BTREE_ASSERT_FLAG(flags); TDB_BTREE_ASSERT_FLAG(flags);
// Init other fields // Init other fields
if (TDB_BTREE_PAGE_IS_LEAF(flags)) { if (isLeaf) {
pPage->kLen = pBt->keyLen; pPage->kLen = pBt->keyLen;
pPage->vLen = pBt->valLen; pPage->vLen = pBt->valLen;
pPage->maxLocal = pBt->maxLeaf; pPage->maxLocal = pBt->maxLeaf;
@ -450,7 +452,22 @@ typedef struct {
} SBtreeBalanceHelper; } SBtreeBalanceHelper;
static int tdbBtreeCopyPageContent(SPage *pFrom, SPage *pTo) { static int tdbBtreeCopyPageContent(SPage *pFrom, SPage *pTo) {
/* TODO */ int nCells = TDB_PAGE_NCELLS(pFrom);
int cCells = TDB_PAGE_CCELLS(pFrom);
int fCell = TDB_PAGE_FCELL(pFrom);
int nFree = TDB_PAGE_NFREE(pFrom);
pTo->pFreeStart = pTo->pCellIdx + nCells * pFrom->szOffset;
memcpy(pTo->pCellIdx, pFrom->pCellIdx, nCells * pFrom->szOffset);
pTo->pFreeEnd = (u8 *)pTo->pPageFtr - (pFrom->pFreeEnd - (u8 *)(pFrom->pPageFtr));
memcpy(pTo->pFreeEnd, pFrom->pFreeEnd, (pFrom->pFreeEnd - (u8 *)pFrom->pPageFtr));
TDB_PAGE_NCELLS_SET(pTo, nCells);
TDB_PAGE_CCELLS_SET(pTo, cCells);
TDB_PAGE_FCELL_SET(pTo, fCell);
TDB_PAGE_NFREE_SET(pTo, nFree);
// TODO: update other fields
return 0; return 0;
} }
@ -698,11 +715,19 @@ static int tdbBtreeBalanceNonRoot(SBTree *pBt, SPage *pParent, int idx) {
static int tdbBtreeBalance(SBtCursor *pCur) { static int tdbBtreeBalance(SBtCursor *pCur) {
int iPage; int iPage;
SPage *pParent; SPage *pParent;
SPage *pPage;
int ret; int ret;
u16 flags;
u8 leaf;
u8 root;
// Main loop to balance the BTree // Main loop to balance the BTree
for (;;) { for (;;) {
iPage = pCur->iPage; iPage = pCur->iPage;
pPage = pCur->pPage;
flags = TDB_PAGE_FLAGS(pPage);
leaf = TDB_BTREE_PAGE_IS_LEAF(flags);
root = TDB_BTREE_PAGE_IS_ROOT(flags);
// TODO: Get the page free space if not get yet // TODO: Get the page free space if not get yet
// if (pPage->nFree < 0) { // if (pPage->nFree < 0) {
@ -711,14 +736,15 @@ static int tdbBtreeBalance(SBtCursor *pCur) {
// } // }
// } // }
if (0 /*TODO: balance is over*/) { // If balance over, break the loop
if (pPage->nOverflow == 0 /* TODO: && pPage->nFree <= */) {
break; break;
} }
if (iPage == 0) { if (iPage == 0) {
// Balance the root page by copy the root page content to // For the root page, only balance when the page is overfull,
// a child page and set the root page as empty first // ignore the case of empty
// ASSERT(TDB_BTREE_PAGE_IS_ROOT(pCur->pPage->pPageHdr->flags)); if (pPage->nOverflow == 0) break;
ret = tdbBtreeBalanceDeeper(pCur->pBt, pCur->pPage, &(pCur->pgStack[1])); ret = tdbBtreeBalanceDeeper(pCur->pBt, pCur->pPage, &(pCur->pgStack[1]));
if (ret < 0) { if (ret < 0) {
@ -730,7 +756,6 @@ static int tdbBtreeBalance(SBtCursor *pCur) {
pCur->pgStack[0] = pCur->pPage; pCur->pgStack[0] = pCur->pPage;
pCur->iPage = 1; pCur->iPage = 1;
pCur->pPage = pCur->pgStack[1]; pCur->pPage = pCur->pgStack[1];
} else { } else {
// Generalized balance step // Generalized balance step
pParent = pCur->pgStack[pCur->iPage - 1]; pParent = pCur->pgStack[pCur->iPage - 1];