enh: read mnode file

source/dnode/mgmt/mgmt_mnode/src/mmFile.c

@@ -17,117 +17,97 @@
 #include "mmInt.h"
 #include "tjson.h"
 
-int32_t mmReadFile(const char *path, SMnodeOpt *pOption) {
-  int32_t   code = TSDB_CODE_INVALID_JSON_FORMAT;
-  int32_t   len = 0;
-  int32_t   maxLen = 4096;
-  char     *content = taosMemoryCalloc(1, maxLen + 1);
-  cJSON    *root = NULL;
-  char      file[PATH_MAX] = {0};
-  TdFilePtr pFile = NULL;
+static int32_t mmDecodeOption(SJson *pJson, SMnodeOpt *pOption) {
+  int32_t code = 0;
 
-  snprintf(file, sizeof(file), "%s%smnode.json", path, TD_DIRSEP);
-  pFile = taosOpenFile(file, TD_FILE_READ);
-  if (pFile == NULL) {
-    code = 0;
-    goto _OVER;
-  }
+  tjsonGetInt32ValueFromDouble(pJson, "deployed", pOption->deploy, code);
+  if (code < 0) return -1;
+  tjsonGetInt32ValueFromDouble(pJson, "selfIndex", pOption->selfIndex, code);
+  if (code < 0) return 0;
 
-  len = (int32_t)taosReadFile(pFile, content, maxLen);
-  if (len <= 0) {
-    dError("failed to read %s since content is null", file);
-    goto _OVER;
-  }
+  SJson *replicas = tjsonGetObjectItem(pJson, "replicas");
+  if (replicas == NULL) return 0;
+  pOption->numOfReplicas = tjsonGetArraySize(replicas);
 
-  content[len] = 0;
-  root = cJSON_Parse(content);
-  if (root == NULL) {
-    dError("failed to read %s since invalid json format", file);
-    goto _OVER;
+  for (int32_t i = 0; i < pOption->numOfReplicas; ++i) {
+    SJson *replica = tjsonGetArrayItem(replicas, i);
+    if (replica == NULL) return -1;
+
+    SReplica *pReplica = pOption->replicas + i;
+    tjsonGetInt32ValueFromDouble(replica, "id", pReplica->id, code);
+    if (code < 0) return -1;
+    code = tjsonGetStringValue(replica, "fqdn", pReplica->fqdn);
+    if (code < 0) return -1;
+    tjsonGetUInt16ValueFromDouble(replica, "port", pReplica->port, code);
+    if (code < 0) return -1;
   }
 
-  cJSON *deployed = cJSON_GetObjectItem(root, "deployed");
-  if (!deployed || deployed->type != cJSON_Number) {
-    dError("failed to read %s since deployed not found", file);
-    goto _OVER;
+  return 0;
+}
+
+int32_t mmReadFile(const char *path, SMnodeOpt *pOption) {
+  int32_t   code = -1;
+  TdFilePtr pFile = NULL;
+  char     *pData = NULL;
+  SJson    *pJson = NULL;
+  char      file[PATH_MAX] = {0};
+  snprintf(file, sizeof(file), "%s%smnode.json", path, TD_DIRSEP);
+
+  if (taosStatFile(file, NULL, NULL) < 0) {
+    dInfo("mnode file:%s not exist", file);
+    return 0;
   }
-  pOption->deploy = deployed->valueint;
 
-  cJSON *selfIndex = cJSON_GetObjectItem(root, "selfIndex");
-  if (selfIndex) {
-    if (selfIndex->type != cJSON_Number) {
-      dError("failed to read %s since selfIndex not found", file);
+  pFile = taosOpenFile(file, TD_FILE_READ);
+  if (pFile == NULL) {
+    terrno = TAOS_SYSTEM_ERROR(errno);
+    dError("failed to open mnode file:%s since %s", file, terrstr());
     goto _OVER;
   }
-    pOption->selfIndex = selfIndex->valueint;
-  }
 
-  cJSON *replicas = cJSON_GetObjectItem(root, "replicas");
-  if (replicas) {
-    if (replicas->type != cJSON_Array) {
-      dError("failed to read %s since replicas not found", file);
+  int64_t size = 0;
+  if (taosFStatFile(pFile, &size, NULL) < 0) {
+    terrno = TAOS_SYSTEM_ERROR(errno);
+    dError("failed to fstat mnode file:%s since %s", file, terrstr());
     goto _OVER;
   }
 
-    int32_t numOfReplicas = cJSON_GetArraySize(replicas);
-    if (numOfReplicas <= 0) {
-      dError("failed to read %s since numOfReplicas:%d invalid", file, numOfReplicas);
+  pData = taosMemoryMalloc(size + 1);
+  if (pData == NULL) {
+    terrno = TSDB_CODE_OUT_OF_MEMORY;
     goto _OVER;
   }
-    pOption->numOfReplicas = numOfReplicas;
-
-    for (int32_t i = 0; i < numOfReplicas; ++i) {
-      SReplica *pReplica = pOption->replicas + i;
-
-      cJSON *replica = cJSON_GetArrayItem(replicas, i);
-      if (replica == NULL) break;
 
-      cJSON *id = cJSON_GetObjectItem(replica, "id");
-      if (id) {
-        if (id->type != cJSON_Number) {
-          dError("failed to read %s since id not found", file);
+  if (taosReadFile(pFile, pData, size) != size) {
+    terrno = TAOS_SYSTEM_ERROR(errno);
+    dError("failed to read mnode file:%s since %s", file, terrstr());
     goto _OVER;
   }
-        if (pReplica) {
-          pReplica->id = id->valueint;
-        }
-      }
 
-      cJSON *fqdn = cJSON_GetObjectItem(replica, "fqdn");
-      if (fqdn) {
-        if (fqdn->type != cJSON_String || fqdn->valuestring == NULL) {
-          dError("failed to read %s since fqdn not found", file);
+  pData[size] = '\0';
+
+  pJson = tjsonParse(pData);
+  if (pJson == NULL) {
+    terrno = TSDB_CODE_INVALID_JSON_FORMAT;
     goto _OVER;
   }
-        if (pReplica) {
-          tstrncpy(pReplica->fqdn, fqdn->valuestring, TSDB_FQDN_LEN);
-        }
-      }
 
-      cJSON *port = cJSON_GetObjectItem(replica, "port");
-      if (port) {
-        if (port->type != cJSON_Number) {
-          dError("failed to read %s since port not found", file);
+  if (mmDecodeOption(pJson, pOption) < 0) {
+    terrno = TSDB_CODE_INVALID_JSON_FORMAT;
     goto _OVER;
   }
-        if (pReplica) {
-          pReplica->port = (uint16_t)port->valueint;
-        }
-      }
-    }
-  }
 
   code = 0;
+  dInfo("succceed to read mnode file %s", file);
 
 _OVER:
-  if (content != NULL) taosMemoryFree(content);
-  if (root != NULL) cJSON_Delete(root);
+  if (pData != NULL) taosMemoryFree(pData);
+  if (pJson != NULL) cJSON_Delete(pJson);
   if (pFile != NULL) taosCloseFile(&pFile);
-  if (code == 0) {
-    dDebug("succcessed to read file %s, deployed:%d", file, pOption->deploy);
-  }
 
-  terrno = code;
+  if (code != 0) {
+    dError("failed to read mnode file:%s since %s", file, terrstr());
+  }
   return code;
 }