more TDB

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

@@ -50,7 +50,6 @@ typedef struct {
 
 static int tdbBtCursorMoveTo(SBtCursor *pCur, const void *pKey, int kLen);
 static int tdbEncodeLength(u8 *pBuf, uint32_t len);
-static int tdbBtCursorMoveToRoot(SBtCursor *pCur);
 static int tdbCompareKeyAndCell(const void *pKey, int kLen, const void *pCell);
 static int tdbDefaultKeyCmprFn(const void *pKey1, int keyLen1, const void *pKey2, int keyLen2);
 static int tdbBtreeOpenImpl(SBTree *pBt);
@@ -114,7 +113,7 @@ int tdbBtreeCursor(SBtCursor *pCur, SBTree *pBt) {
   pCur->pBt = pBt;
   pCur->iPage = -1;
   pCur->pPage = NULL;
-  pCur->idx = 0;
+  pCur->idx = -1;
 
   return 0;
 }
@@ -129,13 +128,45 @@ int tdbBtCursorInsert(SBtCursor *pCur, const void *pKey, int kLen, const void *p
     return -1;
   }
 
+  if (pCur->idx == -1) {
+    ASSERT(pCur->pPage->pPageHdr->nCells == 0);
+    // TODO: insert the K-V pair to idx 0
+  }
+
   return 0;
 }
 
 static int tdbBtCursorMoveTo(SBtCursor *pCur, const void *pKey, int kLen) {
   int     ret;
-  void *pCell;
+  SBTree *pBt;
+  SPager *pPager;
+
+  pBt = pCur->pBt;
+  pPager = pBt->pPager;
+
+  if (pCur->iPage < 0) {
+    ASSERT(pCur->iPage == -1);
+    ASSERT(pCur->idx == -1);
+
+    // Move from the root
+    ret = tdbPagerFetchPage(pPager, pBt->root, &(pCur->pPage), tdbBtreeInitPage, pBt);
+    if (ret < 0) {
+      ASSERT(0);
+      return -1;
+    }
+
+    pCur->iPage = 0;
+
+    if (pCur->pPage->pPageHdr->nCells == 0) {
+      // Current page is empty
+      ASSERT(TDB_FLAG_IS(pCur->pPage->pPageHdr->flags, TDB_BTREE_ROOT | TDB_BTREE_LEAF));
+      return 0;
+    }
 
+    // Search from root page down to leaf
+    {
+      // TODO
+      ASSERT(0);
       // ret = tdbBtCursorMoveToRoot(pCur);
       // if (ret < 0) {
       //   return -1;
@@ -167,6 +198,11 @@ static int tdbBtCursorMoveTo(SBtCursor *pCur, const void *pKey, int kLen) {
 
       //   /* code */
       // }
+    }
+
+  } else {
+    // TODO: Move the cursor from a some position instead of a clear state
+  }
 
   return 0;
 }

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

@@ -130,45 +130,6 @@ int tdbPagerOpenDB(SPager *pPager, SPgno *ppgno, bool toCreate) {
   return 0;
 }
 
-SPage *tdbPagerGet(SPager *pPager, SPgno pgno, bool toLoad) {
-  SPgid  pgid;
-  SPage *pPage;
-  int    ret;
-
-  memcpy(pgid.fileid, pPager->fid, TDB_FILE_ID_LEN);
-  pgid.pgno = pgno;
-
-  // Get page frame from the SPCache
-  pPage = tdbPCacheFetch(pPager->pCache, &pgid, 1);
-  if (pPage == NULL) {
-    // TODO: handle error
-    return NULL;
-  }
-  tdbPCacheFetchFinish(pPager->pCache, pPage);
-
-  // Zero the page or load page content from backend
-  // according to the options
-  if (pPage->pPager == NULL || !toLoad) {
-    if (!toLoad || pgno >= pPager->dbFileSize) {
-      memset(pPage->pData, 0, pPager->pageSize);
-    } else {
-      ret = tdbPagerReadPage(pPager, pPage);
-      if (ret < 0) {
-        // TODO: Need to drop the page
-        return NULL;
-      }
-    }
-
-    if (pPage->pPager) {
-      ASSERT(pPage->pPager == pPager);
-    } else {
-      pPage->pPager = pPager;
-    }
-  }
-
-  return pPage;
-}
-
 int tdbPagerWrite(SPager *pPager, SPage *pPage) {
   int ret;
 

source/libs/tdb/src/inc/tdbBtree.h

@@ -27,7 +27,7 @@ struct SBtCursor {
   SBTree *pBt;
   i8      iPage;
   SPage * pPage;
-  u16     idx;
+  int     idx;
   u16     idxStack[BTREE_MAX_DEPTH + 1];
   SPage * pgStack[BTREE_MAX_DEPTH + 1];
   void *  pBuf;

source/libs/tdb/src/inc/tdbPager.h

@@ -23,7 +23,6 @@ extern "C" {
 int    tdbPagerOpen(SPCache *pCache, const char *fileName, SPager **ppPager);
 int    tdbPagerClose(SPager *pPager);
 int    tdbPagerOpenDB(SPager *pPager, SPgno *ppgno, bool toCreate);
-SPage *tdbPagerGet(SPager *pPager, SPgno pgno, bool toLoad);
 int    tdbPagerWrite(SPager *pPager, SPage *pPage);
 int    tdbPagerBegin(SPager *pPager);
 int    tdbPagerCommit(SPager *pPager);

source/libs/tdb/test/tdbTest.cpp

@@ -16,7 +16,7 @@ TEST(tdb_test, simple_test) {
   GTEST_ASSERT_EQ(ret, 0);
 
   // // Insert some data
-  ret = tdbDbInsert(pDb, "1", 1, "world", 5);
+  ret = tdbDbInsert(pDb, "key1", 4, "value1", 6);
   GTEST_ASSERT_EQ(ret, 0);
 
   ret = tdbDbDrop(pDb);