From 032339949edb84b89962eb613b9d6c5e576e4372 Mon Sep 17 00:00:00 2001
From: Hongze Cheng <hzcheng@taosdata.com>
Date: Mon, 4 Jul 2022 12:24:34 +0000
Subject: [PATCH] more work

---
 source/dnode/vnode/src/inc/vnodeInt.h      |  9 ++++++++-
 source/dnode/vnode/src/meta/metaSnapshot.c | 12 +++++++-----
 source/dnode/vnode/src/vnd/vnodeSnapshot.c |  7 +++----
 3 files changed, 18 insertions(+), 10 deletions(-)

diff --git a/source/dnode/vnode/src/inc/vnodeInt.h b/source/dnode/vnode/src/inc/vnodeInt.h
index 9f7b1ed783..4850aab2e0 100644
--- a/source/dnode/vnode/src/inc/vnodeInt.h
+++ b/source/dnode/vnode/src/inc/vnodeInt.h
@@ -62,6 +62,7 @@ typedef struct SMetaSnapReader SMetaSnapReader;
 typedef struct SMetaSnapWriter SMetaSnapWriter;
 typedef struct STsdbSnapReader STsdbSnapReader;
 typedef struct STsdbSnapWriter STsdbSnapWriter;
+typedef struct SSnapDataHdr    SSnapDataHdr;
 
 #define VNODE_META_DIR  "meta"
 #define VNODE_TSDB_DIR  "tsdb"
@@ -177,7 +178,7 @@ void*   tdUidStoreFree(STbUidStore* pStore);
 // SMetaSnapReader ========================================
 int32_t metaSnapReaderOpen(SMeta* pMeta, int64_t sver, int64_t ever, SMetaSnapReader** ppReader);
 int32_t metaSnapReaderClose(SMetaSnapReader** ppReader);
-int32_t metaSnapRead(SMetaSnapReader* pReader, uint8_t** ppData, int64_t* nDatap);
+int32_t metaSnapRead(SMetaSnapReader* pReader, uint8_t** ppData);
 // SMetaSnapWriter ========================================
 // STsdbSnapReader ========================================
 int32_t tsdbSnapReaderOpen(STsdb* pTsdb, int64_t sver, int64_t ever, STsdbSnapReader** ppReader);
@@ -292,6 +293,12 @@ struct SSma {
 // sma
 void smaHandleRes(void* pVnode, int64_t smaId, const SArray* data);
 
+struct SSnapDataHdr {
+  int8_t  type;
+  int64_t size;
+  uint8_t data[];
+};
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/source/dnode/vnode/src/meta/metaSnapshot.c b/source/dnode/vnode/src/meta/metaSnapshot.c
index 9252f8d23d..013ec19411 100644
--- a/source/dnode/vnode/src/meta/metaSnapshot.c
+++ b/source/dnode/vnode/src/meta/metaSnapshot.c
@@ -65,7 +65,7 @@ int32_t metaSnapReaderClose(SMetaSnapReader** ppReader) {
   return 0;
 }
 
-int32_t metaSnapRead(SMetaSnapReader* pReader, uint8_t** ppData, int64_t* nDatap) {
+int32_t metaSnapRead(SMetaSnapReader* pReader, uint8_t** ppData) {
   const void* pKey = NULL;
   const void* pData = NULL;
   int32_t     nKey = 0;
@@ -79,20 +79,22 @@ int32_t metaSnapRead(SMetaSnapReader* pReader, uint8_t** ppData, int64_t* nDatap
     }
 
     if (((STbDbKey*)pData)->version < pReader->sver) {
+      tdbTbcMoveToNext(pReader->pTbc);
       continue;
     }
 
+    tdbTbcMoveToNext(pReader->pTbc);
     break;
   }
 
   // copy the data
-  if (tRealloc(ppData, nData) < 0) {
+  if (tRealloc(ppData, sizeof(SSnapDataHdr) + nData) < 0) {
     code = TSDB_CODE_OUT_OF_MEMORY;
     return code;
   }
-
-  memcpy(*ppData, pData, nData);
-  *nDatap = nData;
+  ((SSnapDataHdr*)(*ppData))->type = 0;  // TODO: use macro
+  ((SSnapDataHdr*)(*ppData))->size = nData;
+  memcpy(((SSnapDataHdr*)(*ppData))->data, pData, nData);
   return code;
 }
 
diff --git a/source/dnode/vnode/src/vnd/vnodeSnapshot.c b/source/dnode/vnode/src/vnd/vnodeSnapshot.c
index fbc1a08401..f760d9174e 100644
--- a/source/dnode/vnode/src/vnd/vnodeSnapshot.c
+++ b/source/dnode/vnode/src/vnd/vnodeSnapshot.c
@@ -27,7 +27,6 @@ struct SVSnapReader {
   int8_t           tsdbDone;
   STsdbSnapReader *pTsdbReader;
   uint8_t         *pData;
-  int64_t          nData;
 };
 
 int32_t vnodeSnapReaderOpen(SVnode *pVnode, int64_t sver, int64_t ever, SVSnapReader **ppReader) {
@@ -73,7 +72,7 @@ int32_t vnodeSnapRead(SVSnapReader *pReader, uint8_t **ppData, uint32_t *nData)
   int32_t code = 0;
 
   if (!pReader->metaDone) {
-    code = metaSnapRead(pReader->pMetaReader, &pReader->pData, &pReader->nData);
+    code = metaSnapRead(pReader->pMetaReader, &pReader->pData);
     if (code) {
       if (code == TSDB_CODE_VND_READ_END) {
         pReader->metaDone = 1;
@@ -82,7 +81,7 @@ int32_t vnodeSnapRead(SVSnapReader *pReader, uint8_t **ppData, uint32_t *nData)
       }
     } else {
       *ppData = pReader->pData;
-      *nData = pReader->nData;
+      *nData = sizeof(SSnapDataHdr) + ((SSnapDataHdr *)pReader->pData)->size;
       goto _exit;
     }
   }
@@ -97,7 +96,7 @@ int32_t vnodeSnapRead(SVSnapReader *pReader, uint8_t **ppData, uint32_t *nData)
       }
     } else {
       *ppData = pReader->pData;
-      *nData = pReader->nData;
+      *nData = sizeof(SSnapDataHdr) + ((SSnapDataHdr *)pReader->pData)->size;
       goto _exit;
     }
   }