vnode snapshot 2

source/dnode/vnode/CMakeLists.txt

@@ -14,6 +14,7 @@ target_sources(
     "src/vnd/vnodeSvr.c"
     "src/vnd/vnodeSync.c"
     "src/vnd/vnodeSnapshot.c"
+    "src/vnd/vnodeUtil.c"
 
     # meta
     "src/meta/metaOpen.c"

source/dnode/vnode/src/inc/vnodeInt.h

@@ -69,8 +69,10 @@ typedef struct STsdbSnapshotReader STsdbSnapshotReader;
 #define VNODE_RSMA2_DIR "rsma2"
 
 // vnd.h
-void* vnodeBufPoolMalloc(SVBufPool* pPool, int size);
+void*   vnodeBufPoolMalloc(SVBufPool* pPool, int size);
-void  vnodeBufPoolFree(SVBufPool* pPool, void* p);
+void    vnodeBufPoolFree(SVBufPool* pPool, void* p);
+int32_t vnodeRealloc(void** pp, int32_t size);
+void    vnodeFree(void* p);
 
 // meta
 typedef struct SMCtbCursor SMCtbCursor;

source/dnode/vnode/src/meta/metaSnapshot.c

@@ -16,20 +16,78 @@
 #include "meta.h"
 
 struct SMetaSnapshotReader {
-  // TODO
+  SMeta*  pMeta;
+  TBC*    pTbc;
+  int64_t sver;
+  int64_t ever;
 };
 
 int32_t metaSnapshotReaderOpen(SMeta* pMeta, SMetaSnapshotReader** ppReader, int64_t sver, int64_t ever) {
-  // TODO
+  int32_t              code = 0;
-  return 0;
+  int32_t              c = 0;
+  SMetaSnapshotReader* pMetaReader = NULL;
+
+  pMetaReader = (SMetaSnapshotReader*)taosMemoryCalloc(1, sizeof(*pMetaReader));
+  if (pMetaReader == NULL) {
+    code = TSDB_CODE_OUT_OF_MEMORY;
+    goto _err;
+  }
+  pMetaReader->pMeta = pMeta;
+  pMetaReader->sver = sver;
+  pMetaReader->ever = ever;
+  code = tdbTbcOpen(pMeta->pTbDb, &pMetaReader->pTbc, NULL);
+  if (code) {
+    goto _err;
+  }
+
+  code = tdbTbcMoveTo(pMetaReader->pTbc, &(STbDbKey){.version = sver, .uid = INT64_MIN}, sizeof(STbDbKey), &c);
+  if (code) {
+    goto _err;
+  }
+
+  *ppReader = pMetaReader;
+  return code;
+
+_err:
+  *ppReader = NULL;
+  return code;
 }
 
 int32_t metaSnapshotReaderClose(SMetaSnapshotReader* pReader) {
-  // TODO
+  if (pReader) {
+    tdbTbcClose(pReader->pTbc);
+    taosMemoryFree(pReader);
+  }
   return 0;
 }
 
-int32_t metaSnapshotRead(SMetaSnapshotReader* pReader, void** ppData, uint32_t* nData) {
+int32_t metaSnapshotRead(SMetaSnapshotReader* pReader, void** ppData, uint32_t* nDatap) {
-  // TODO
+  const void* pKey = NULL;
-  return 0;
+  const void* pData = NULL;
+  int32_t     nKey = 0;
+  int32_t     nData = 0;
+  int32_t     code = 0;
+
+  for (;;) {
+    code = tdbTbcGet(pReader->pTbc, &pKey, &nKey, &pData, &nData);
+    if (code || ((STbDbKey*)pData)->version > pReader->ever) {
+      return TSDB_CODE_VND_READ_END;
+    }
+
+    if (((STbDbKey*)pData)->version < pReader->sver) {
+      continue;
+    }
+
+    break;
+  }
+
+  // copy the data
+  if (vnodeRealloc(ppData, nData) < 0) {
+    code = TSDB_CODE_OUT_OF_MEMORY;
+    return code;
+  }
+
+  memcpy(*ppData, pData, nData);
+  *nDatap = nData;
+  return code;
 }

source/dnode/vnode/src/vnd/vnodeUtil.c

@@ -0,0 +1,45 @@
+/*
+ * Copyright (c) 2019 TAOS Data, Inc. <jhtao@taosdata.com>
+ *
+ * This program is free software: you can use, redistribute, and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3
+ * or later ("AGPL"), as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "vnd.h"
+
+int32_t vnodeRealloc(void** pp, int32_t size) {
+  uint8_t* p = NULL;
+  int32_t  csize = 0;
+
+  if (*pp) {
+    p = (uint8_t*)(*pp) - sizeof(int32_t);
+    csize = *(int32_t*)p;
+  }
+
+  if (csize >= size) {
+    return 0;
+  }
+
+  p = (uint8_t*)taosMemoryRealloc(p, size);
+  if (p == NULL) {
+    return TSDB_CODE_OUT_OF_MEMORY;
+  }
+  *(int32_t*)p = size;
+  *pp = p + sizeof(int32_t);
+
+  return 0;
+}
+
+void vnodeFree(void* p) {
+  if (p) {
+    taosMemoryFree(((uint8_t*)p) - sizeof(int32_t));
+  }
+}