make wal meta serialized and flushed into disk

source/libs/wal/inc/walInt.h

@@ -83,8 +83,8 @@ int walReadMeta(SWal* pWal);
 int walWriteMeta(SWal* pWal);
 int walRollFileInfo(SWal* pWal);
 
-char* walFileInfoSerialize(SWal* pWal);
-SArray* walFileInfoDeserialize(const char* bytes);
+char* walMetaSerialize(SWal* pWal);
+int walMetaDeserialize(SWal* pWal, const char* bytes);
 //meta section end
 
 int64_t walGetSeq();

source/libs/wal/src/walMeta.c

@@ -47,49 +47,74 @@ int walRollFileInfo(SWal* pWal) {
   return 0;
 }
 
-char* walFileInfoSerialize(SWal* pWal) {
+char* walMetaSerialize(SWal* pWal) {
   char buf[30];
   if(pWal == NULL || pWal->fileInfoSet == NULL) return 0;
   int sz = pWal->fileInfoSet->size;
-  cJSON* root = cJSON_CreateArray();
-  cJSON* field;
-  if(root == NULL) {
+  cJSON* pRoot = cJSON_CreateObject();
+  cJSON* pMeta = cJSON_CreateObject();
+  cJSON* pFiles = cJSON_CreateArray();
+  cJSON* pField;
+  if(pRoot == NULL || pMeta == NULL || pFiles == NULL) {
     //TODO
     return NULL;
   }
+  cJSON_AddItemToObject(pRoot, "meta", pMeta);
+  sprintf(buf, "%" PRId64, pWal->firstVersion);
+  cJSON_AddStringToObject(pMeta, "firstVer", buf);
+  sprintf(buf, "%" PRId64, pWal->snapshotVersion);
+  cJSON_AddStringToObject(pMeta, "snapshotVer", buf);
+  sprintf(buf, "%" PRId64, pWal->commitVersion);
+  cJSON_AddStringToObject(pMeta, "commitVer", buf);
+  sprintf(buf, "%" PRId64, pWal->lastVersion);
+  cJSON_AddStringToObject(pMeta, "lastVer", buf);
+
+  cJSON_AddItemToObject(pRoot, "files", pFiles);
   WalFileInfo* pData = pWal->fileInfoSet->pData;
   for(int i = 0; i < sz; i++) {
     WalFileInfo* pInfo = &pData[i];
-    cJSON_AddItemToArray(root, field = cJSON_CreateObject());
-    if(field == NULL) {
-      cJSON_Delete(root);
+    cJSON_AddItemToArray(pFiles, pField = cJSON_CreateObject());
+    if(pField == NULL) {
+      cJSON_Delete(pRoot);
       return NULL;
     }
     //cjson only support int32_t or double
     //string are used to prohibit the loss of precision
-    sprintf(buf, "%ld", pInfo->firstVer);
-    cJSON_AddStringToObject(field, "firstVer", buf);
-    sprintf(buf, "%ld", pInfo->lastVer);
-    cJSON_AddStringToObject(field, "lastVer", buf);
-    sprintf(buf, "%ld", pInfo->createTs);
-    cJSON_AddStringToObject(field, "createTs", buf);
-    sprintf(buf, "%ld", pInfo->closeTs);
-    cJSON_AddStringToObject(field, "closeTs", buf);
-    sprintf(buf, "%ld", pInfo->fileSize);
-    cJSON_AddStringToObject(field, "fileSize", buf);
+    sprintf(buf, "%" PRId64, pInfo->firstVer);
+    cJSON_AddStringToObject(pField, "firstVer", buf);
+    sprintf(buf, "%" PRId64, pInfo->lastVer);
+    cJSON_AddStringToObject(pField, "lastVer", buf);
+    sprintf(buf, "%" PRId64, pInfo->createTs);
+    cJSON_AddStringToObject(pField, "createTs", buf);
+    sprintf(buf, "%" PRId64, pInfo->closeTs);
+    cJSON_AddStringToObject(pField, "closeTs", buf);
+    sprintf(buf, "%" PRId64, pInfo->fileSize);
+    cJSON_AddStringToObject(pField, "fileSize", buf);
   }
-  return cJSON_Print(root);
+  return cJSON_Print(pRoot);
 }
 
-SArray* walFileInfoDeserialize(const char* bytes) {
-  cJSON *root, *pInfoJson, *pField;
-  root = cJSON_Parse(bytes);
-  int sz = cJSON_GetArraySize(root);
+int walMetaDeserialize(SWal* pWal, const char* bytes) {
+  ASSERT(taosArrayGetSize(pWal->fileInfoSet) == 0);
+  cJSON *pRoot, *pMeta, *pFiles, *pInfoJson, *pField;
+  pRoot = cJSON_Parse(bytes);
+  pMeta = cJSON_GetObjectItem(pRoot, "meta");
+  pField = cJSON_GetObjectItem(pMeta, "firstVer");
+  pWal->firstVersion = atoll(cJSON_GetStringValue(pField));
+  pField = cJSON_GetObjectItem(pMeta, "snapshotVer");
+  pWal->snapshotVersion = atoll(cJSON_GetStringValue(pField));
+  pField = cJSON_GetObjectItem(pMeta, "commitVer");
+  pWal->commitVersion = atoll(cJSON_GetStringValue(pField));
+  pField = cJSON_GetObjectItem(pMeta, "lastVer");
+  pWal->lastVersion = atoll(cJSON_GetStringValue(pField));
+
+  pFiles = cJSON_GetObjectItem(pRoot, "files");
+  int sz = cJSON_GetArraySize(pFiles);
   //deserialize
   SArray* pArray = taosArrayInit(sz, sizeof(WalFileInfo));
   WalFileInfo *pData = pArray->pData;
   for(int i = 0; i < sz; i++) {
-    cJSON* pInfoJson = cJSON_GetArrayItem(root, i);
+    cJSON* pInfoJson = cJSON_GetArrayItem(pFiles, i);
     WalFileInfo* pInfo = &pData[i];
     pField = cJSON_GetObjectItem(pInfoJson, "firstVer");
     pInfo->firstVer = atoll(cJSON_GetStringValue(pField));
@@ -103,7 +128,8 @@ SArray* walFileInfoDeserialize(const char* bytes) {
     pInfo->fileSize = atoll(cJSON_GetStringValue(pField));
   }
   taosArraySetSize(pArray, sz);
-  return pArray;
+  pWal->fileInfoSet = pArray;
+  return 0;
 }
 
 static inline int walBuildMetaName(SWal* pWal, int metaVer, char* buf) {
@@ -144,7 +170,7 @@ int walWriteMeta(SWal* pWal) {
   if(metaTfd < 0) {
     return -1;
   }
-  char* serialized = walFileInfoSerialize(pWal);
+  char* serialized = walMetaSerialize(pWal);
   int len = strlen(serialized);
   if(len != tfWrite(metaTfd, serialized, len)) {
     //TODO:clean file
@@ -183,8 +209,8 @@ int walReadMeta(SWal* pWal) {
     return -1;
   }
   //load into fileInfoSet
-  pWal->fileInfoSet = walFileInfoDeserialize(buf);
-  if(pWal->fileInfoSet == NULL) {
+  int code = walMetaDeserialize(pWal, buf);
+  if(code != 0) {
     free(buf);
     return -1;
   }

source/libs/wal/src/walMgmt.c

@@ -175,8 +175,6 @@ static void walFreeObj(void *wal) {
   tfClose(pWal->writeIdxTfd);
   taosArrayDestroy(pWal->fileInfoSet);
   pWal->fileInfoSet = NULL;
-  taosArrayDestroy(pWal->fileInfoSet);
-  pWal->fileInfoSet = NULL;
   pthread_mutex_destroy(&pWal->mutex);
   tfree(pWal);
 }

source/libs/wal/test/walMetaTest.cpp

@@ -92,7 +92,7 @@ TEST_F(WalCleanEnv, serialize) {
   ASSERT(code == 0);
   code = walRollFileInfo(pWal);
   ASSERT(code == 0);
-  char*ss = walFileInfoSerialize(pWal);
+  char*ss = walMetaSerialize(pWal);
   printf("%s\n", ss);
   code = walWriteMeta(pWal);
   ASSERT(code == 0);
@@ -113,20 +113,19 @@ TEST_F(WalCleanEnv, removeOldMeta) {
 TEST_F(WalKeepEnv, readOldMeta) {
   int code = walRollFileInfo(pWal);
   ASSERT(code == 0);
-  ASSERT(pWal->fileInfoSet != NULL);
   code = walWriteMeta(pWal);
   ASSERT(code == 0);
   code = walRollFileInfo(pWal);
   ASSERT(code == 0);
   code = walWriteMeta(pWal);
   ASSERT(code == 0);
-  char*oldss = walFileInfoSerialize(pWal);
+  char*oldss = walMetaSerialize(pWal);
 
   TearDown();
   SetUp();
   code = walReadMeta(pWal);
   ASSERT(code == 0);
-  char* newss = walFileInfoSerialize(pWal);
+  char* newss = walMetaSerialize(pWal);
 
   int len = strlen(oldss);
   ASSERT_EQ(len, strlen(newss));