more TDB

source/libs/tdb/src/db/tdbBtree.c

@@ -415,6 +415,7 @@ static int tdbBtreeInitPage(SPage *pPage, void *arg) {
 
   // TODO: need to update the SPage.nFree
   pPage->nFree = pPage->pFreeEnd - pPage->pFreeStart;
+  pPage->nOverflow = 0;
 
   return 0;
 }
@@ -445,7 +446,7 @@ typedef struct {
   SBTree *pBt;
   SPage  *pParent;
   int     idx;
-  i8      nOldPages;
+  i8      nOld;
   SPage  *pOldPages[3];
   i8      nNewPages;
   SPage  *pNewPages[5];
@@ -514,68 +515,71 @@ static int tdbBtreeBalanceDeeper(SBTree *pBt, SPage *pRoot, SPage **ppChild) {
 }
 
 static int tdbBtreeBalanceStep1(SBtreeBalanceHelper *pBlh) {
-#if 0
+  int          nCells;
-  int    i;
+  int          i;
-  SPage *pParent;
+  int          idxStart;
-  int    nDiv;
+  int          nChild;
-  SPgno  pgno;
+  int          ret;
-  SPage *pPage;
+  SPage       *pParent;
-  int    ret;
+  SPgno        pgno;
+  SCell       *pCell;
+  SCellDecoder cd;
+  SBTree      *pBt;
 
   pParent = pBlh->pParent;
-  i = pParent->pPageHdr->nCells + pParent->nOverflow;
+  nCells = TDB_PAGE_NCELLS(pParent);
+  nChild = nCells + 1;
+  pBt = pBlh->pBt;
 
-  if (i < 1) {
+  // TODO:  ASSERT below needs to be removed
-    nDiv = 0;
+  ASSERT(pParent->nOverflow == 0);
+  ASSERT(pBlh->idx <= nCells);
+
+  if (nChild < 3) {
+    idxStart = 0;
+    pBlh->nOld = nChild;
   } else {
     if (pBlh->idx == 0) {
-      nDiv = 0;
+      idxStart = 0;
-    } else if (pBlh->idx == i) {
+    } else if (pBlh->idx == nCells) {
-      nDiv = i - 2;
+      idxStart = pBlh->idx - 2;
     } else {
-      nDiv = pBlh->idx - 1;
+      idxStart = pBlh->idx - 1;
     }
-    i = 2;
+    pBlh->nOld = 3;
   }
-  pBlh->nOldPages = i + 1;
 
-  if (i + nDiv - pParent->nOverflow == pParent->pPageHdr->nCells) {
+  i = pBlh->nOld - 1;
-    // pgno = pParent->pPageHdr->rChild;
+
+  if (idxStart + i == nCells) {
+    pgno = ((SBtPageHdr *)(pParent->pAmHdr))[0].rChild;
   } else {
-    ASSERT(0);
+    pCell = TDB_PAGE_CELL_AT(pParent, idxStart + i);
-    // TODO
+    // TODO: no need to decode the payload part, and even the kLen, vLen part
-    pgno = 0;
+    // we only need the pgno part
+    ret = tdbBtreeDecodeCell(pParent, pCell, &cd);
+    if (ret < 0) {
+      ASSERT(0);
+      return -1;
+    }
+    pgno = cd.pgno;
   }
   for (;;) {
-    ret = tdbPagerFetchPage(pBlh->pBt->pPager, pgno, &pPage, tdbBtreeInitPage, pBlh->pBt);
+    ret = tdbPagerFetchPage(pBt->pPager, pgno, &(pBlh->pOldPages[i]), tdbBtreeInitPage, pBt);
     if (ret < 0) {
       ASSERT(0);
       return -1;
     }
 
-    pBlh->pOldPages[i] = pPage;
+    // Loop over
-
     if ((i--) == 0) break;
 
-    if (pParent->nOverflow && i + nDiv == pParent->aiOvfl[0]) {
+    {
-      // pCellDiv[i] = pParent->apOvfl[0];
+      // TODO
-      // pgno = 0;
+      // ASSERT(0);
-      // szNew[i] = tdbPageCellSize(pPage, pCell);
-      pParent->nOverflow = 0;
-    } else {
-      // pCellDiv[i] = TDB_PAGE_CELL_AT(pPage, i + nDiv - pParent->nOverflow);
-      // pgno = 0;
-      // szNew[i] = tdbPageCellSize(pPage, pCell);
-
-      // Drop the cell from the page
-      // ret = tdbPageDropCell(pPage, i + nDiv - pParent->nOverflow, szNew[i]);
-      // if (ret < 0) {
-      //   return -1;
-      // }
     }
   }
 
-#endif
   return 0;
 }
 
@@ -587,7 +591,7 @@ static int tdbBtreeBalanceStep2(SBtreeBalanceHelper *pBlh) {
   int    limit;
   SCell *pCell;
 
-  for (int i = 0; i < pBlh->nOldPages; i++) {
+  for (int i = 0; i < pBlh->nOld; i++) {
     pPage = pBlh->pOldPages[i];
     oidx = 0;
     cidx = 0;
@@ -631,7 +635,7 @@ static int tdbBtreeBalanceStep2(SBtreeBalanceHelper *pBlh) {
 }
 
 static int tdbBtreeBalanceStep3(SBtreeBalanceHelper *pBlh) {
-  for (int i = 0; i < pBlh->nOldPages; i++) {
+  for (int i = 0; i < pBlh->nOld; i++) {
     /* code */
   }
 
@@ -657,6 +661,8 @@ static int tdbBtreeBalanceNonRoot(SBTree *pBt, SPage *pParent, int idx) {
   int                 ret;
   SBtreeBalanceHelper blh;
 
+  ASSERT(!TDB_BTREE_PAGE_IS_LEAF(TDB_PAGE_FLAGS(pParent)));
+
   blh.pBt = pBt;
   blh.pParent = pParent;
   blh.idx = idx;
@@ -738,7 +744,8 @@ static int tdbBtreeBalance(SBtCursor *pCur) {
     //   }
     // }
 
-    // If balance over, break the loop
+    // when the page is not overflow and not too empty, the balance work
+    // is finished. Just break out the balance loop.
     if (pPage->nOverflow == 0 /* TODO: && pPage->nFree <= */) {
       break;
     }
@@ -760,7 +767,7 @@ static int tdbBtreeBalance(SBtCursor *pCur) {
       pCur->pPage = pCur->pgStack[1];
     } else {
       // Generalized balance step
-      pParent = pCur->pgStack[pCur->iPage - 1];
+      pParent = pCur->pgStack[iPage - 1];
 
       ret = tdbBtreeBalanceNonRoot(pCur->pBt, pParent, pCur->idxStack[pCur->iPage - 1]);
       if (ret < 0) {

source/libs/tdb/test/tdbTest.cpp

@@ -19,7 +19,7 @@ TEST(tdb_test, simple_test) {
     char key[64];
     char val[64];
 
-    for (int i = 1; i <= 65; i++) {
+    for (int i = 1; i <= 1000; i++) {
       sprintf(key, "key%d", i);
       sprintf(val, "value%d", i);
       ret = tdbDbInsert(pDb, key, strlen(key), val, strlen(val));