xxq250
/
homework-jianmu
1
0
Fork 0
Code Issues Pull Requests 1 Actions Packages Projects Releases Wiki Activity

more

This commit is contained in:
Hongze Cheng 2022-02-25 08:31:16 +00:00
parent 7c7c0fb5f6
commit 7cd83134d2
1 changed files with 57 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

51
source/libs/tdb/src/db/tdbBtree.c
View File

@ -35,11 +35,13 @@ typedef struct SPgHdr {
u16 pCell; u16 pCell;
i32 kLen; i32 kLen;
i32 vLen; i32 vLen;
SPgno rightChild;
} SPgHdr; } SPgHdr;
typedef struct SBtPage { typedef struct SBtPage {
SPgHdr *pHdr; SPgHdr *pHdr;
u16 * aCellIdx; u16 * aCellIdx;
u8 * aData;
} SBtPage; } SBtPage;
struct SBtCursor { struct SBtCursor {
@ -48,10 +50,16 @@ struct SBtCursor {
SBtPage *pPage; SBtPage *pPage;
}; };
typedef struct SFreeCell {
u16 size;
u16 next;
} SFreeCell;
static int tdbBtCursorMoveTo(SBtCursor *pCur, const void *pKey, int kLen); static int tdbBtCursorMoveTo(SBtCursor *pCur, const void *pKey, int kLen);
static int tdbEncodeLength(u8 *pBuf, uint len); static int tdbEncodeLength(u8 *pBuf, uint len);
static int tdbBtCursorMoveToRoot(SBtCursor *pCur); static int tdbBtCursorMoveToRoot(SBtCursor *pCur);
static int tdbInitBtPage(SPage *pPage, SBtPage **ppBtPage); static int tdbInitBtPage(SPage *pPage, SBtPage **ppBtPage);
static int tdbCompareKeyAndCell(const void *pKey, int kLen, const void *pCell);
int tdbBtreeOpen(SPgno root, SBTree **ppBt) { int tdbBtreeOpen(SPgno root, SBTree **ppBt) {
*ppBt = NULL; *ppBt = NULL;
@ -93,9 +101,37 @@ int tdbBtCursorInsert(SBtCursor *pCur, const void *pKey, int kLen, const void *p
static int tdbBtCursorMoveTo(SBtCursor *pCur, const void *pKey, int kLen) { static int tdbBtCursorMoveTo(SBtCursor *pCur, const void *pKey, int kLen) {
int ret; int ret;
SBtPage *pBtPage;
void * pCell;
ret = tdbBtCursorMoveToRoot(pCur); ret = tdbBtCursorMoveToRoot(pCur);
// TODO if (ret < 0) {
return -1;
}
for (;;) {
int lidx, ridx, midx, c;
pBtPage = pCur->pPage;
lidx = 0;
ridx = pBtPage->pHdr->nCells - 1;
while (lidx <= ridx) {
midx = (lidx + ridx) >> 1;
pCell = (void *)(pBtPage->aData + pBtPage->aCellIdx[midx]);
c = tdbCompareKeyAndCell(pKey, kLen, pCell);
if (c == 0) {
break;
} else if (c < 0) {
lidx = lidx + 1;
} else {
ridx = ridx - 1;
}
}
/* code */
}
return 0; return 0;
} }
@ -181,6 +217,17 @@ static int tdbBtCursorMoveToRoot(SBtCursor *pCur) {
} }
static int tdbInitBtPage(SPage *pPage, SBtPage **ppBtPage) { static int tdbInitBtPage(SPage *pPage, SBtPage **ppBtPage) {
// TODO SBtPage *pBtPage;
pBtPage = (SBtPage *)pPage->pExtra;
pBtPage->pHdr = (SPgHdr *)pPage->pData;
pBtPage->aCellIdx = (u16 *)(&((pBtPage->pHdr)[1]));
pBtPage->aData = (u8 *)pPage->pData;
*ppBtPage = pBtPage;
return 0;
}
static int tdbCompareKeyAndCell(const void *pKey, int kLen, const void *pCell) {
/* TODO */
return 0; return 0;
} }