提交 7be2d80b 编写于 作者: H Hongze Cheng

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上级 34ccd1b2
......@@ -48,6 +48,7 @@ int tdbBtreeClose(SBTree *pBt) {
int tdbBtreeCursor(SBTree *pBt, SBtCursor *pCur) {
pCur->pBt = pBt;
pCur->iPage = -1;
/* TODO */
return 0;
}
......@@ -68,154 +69,4 @@ static int tdbBtreeCursorMoveToRoot(SBtCursor *pCur) {
}
return 0;
}
#if 0
struct SBtCursor {
SBTree *pBtree;
SPgno pgno;
SPage * pPage; // current page traversing
};
typedef struct {
SPgno pgno;
pgsz_t offset;
} SBtIdx;
// Btree page header definition
typedef struct __attribute__((__packed__)) {
uint8_t flag; // page flag
int32_t vlen; // value length of current page, TDB_VARIANT_LEN for variant length
uint16_t nPayloads; // number of total payloads
pgoff_t freeOff; // free payload offset
pgsz_t fragSize; // total fragment size
pgoff_t offPayload; // payload offset
SPgno rChildPgno; // right most child page number
} SBtPgHdr;
typedef int (*BtreeCmprFn)(const void *, const void *);
#define BTREE_PAGE_HDR(pPage) NULL /* TODO */
#define BTREE_PAGE_PAYLOAD_AT(pPage, idx) NULL /*TODO*/
#define BTREE_PAGE_IS_LEAF(pPage) 0 /* TODO */
static int btreeCreate(SBTree **ppBt);
static int btreeDestroy(SBTree *pBt);
static int btreeCursorMoveToChild(SBtCursor *pBtCur, SPgno pgno);
int btreeOpen(SBTree **ppBt, SPgFile *pPgFile) {
SBTree *pBt;
int ret;
ret = btreeCreate(&pBt);
if (ret != 0) {
return -1;
}
*ppBt = pBt;
return 0;
}
int btreeClose(SBTree *pBt) {
// TODO
return 0;
}
static int btreeCreate(SBTree **ppBt) {
SBTree *pBt;
pBt = (SBTree *)calloc(1, sizeof(*pBt));
if (pBt == NULL) {
return -1;
}
// TODO
return 0;
}
static int btreeDestroy(SBTree *pBt) {
if (pBt) {
free(pBt);
}
return 0;
}
int btreeCursorOpen(SBtCursor *pBtCur, SBTree *pBt) {
// TODO
return 0;
}
int btreeCursorClose(SBtCursor *pBtCur) {
// TODO
return 0;
}
int btreeCursorMoveTo(SBtCursor *pBtCur, int kLen, const void *pKey) {
SPage * pPage;
SBtPgHdr * pBtPgHdr;
SPgFile * pPgFile;
SPgno childPgno;
SPgno rootPgno;
int nPayloads;
void * pPayload;
BtreeCmprFn cmpFn;
// 1. Move the cursor to the root page
if (rootPgno == TDB_IVLD_PGNO) {
// No any data in this btree, just return not found (TODO)
return 0;
} else {
// Load the page from the file by the SPgFile handle
pPage = pgFileFetch(pPgFile, rootPgno);
pBtCur->pPage = pPage;
}
// 2. Loop to search over the whole tree
for (;;) {
int lidx, ridx, midx, cret;
pPage = pBtCur->pPage;
pBtPgHdr = BTREE_PAGE_HDR(pPage);
nPayloads = pBtPgHdr->nPayloads;
// Binary search the page
lidx = 0;
ridx = nPayloads - 1;
midx = (lidx + ridx) >> 1;
for (;;) {
// get the payload ptr at midx
pPayload = BTREE_PAGE_PAYLOAD_AT(pPage, midx);
// the payload and the key
cret = cmpFn(pKey, pPayload);
if (cret < 0) {
/* TODO */
} else if (cret > 0) {
/* TODO */
} else {
/* TODO */
}
if (lidx > ridx) break;
midx = (lidx + ridx) >> 1;
}
if (BTREE_PAGE_IS_LEAF(pPage)) {
/* TODO */
break;
} else {
/* TODO */
btreeCursorMoveToChild(pBtCur, childPgno);
}
}
return 0;
}
static int btreeCursorMoveToChild(SBtCursor *pBtCur, SPgno pgno) {
SPgFile *pPgFile;
// TODO
return 0;
}
#endif
\ No newline at end of file
}
\ No newline at end of file
......@@ -23,22 +23,6 @@ extern "C" {
typedef struct SBTree SBTree;
typedef struct SBtCursor SBtCursor;
#if 0
// SBTree
int btreeOpen(SBTree **ppBt, SPgFile *pPgFile);
int btreeClose(SBTree *pBt);
// SBtCursor
int btreeCursorOpen(SBtCursor *pBtCur, SBTree *pBt);
int btreeCursorClose(SBtCursor *pBtCur);
int btreeCursorMoveTo(SBtCursor *pBtCur, int kLen, const void *pKey);
int btreeCursorNext(SBtCursor *pBtCur);
struct SBTree {
SPgno root;
};
#endif
#ifdef __cplusplus
}
#endif
......
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