[TD-10430] add dnode cfg for dnode module

source/server/dnode/inc/dnodeCfg.h

+/*
+ * 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/>.
+ */
+
+#ifndef _TD_DNODE_CFG_H_
+#define _TD_DNODE_CFG_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+#include "dnodeInt.h"
+
+typedef struct DnCfg {
+  Dnode *         dnode;
+  int32_t         dnodeId;
+  int32_t         dropped;
+  char            clusterId[TSDB_CLUSTER_ID_LEN];
+  char            file[PATH_MAX + 20];
+  pthread_mutex_t mutex;
+} DnCfg;
+
+int32_t dnodeInitCfg(Dnode *dnode, DnCfg **cfg);
+void    dnodeCleanupCfg(Dnode *dnode, DnCfg **cfg);
+void    dnodeUpdateCfg(DnCfg *cfg, SDnodeCfg *data);
+int32_t dnodeGetDnodeId(DnCfg *cfg);
+void    dnodeGetClusterId(DnCfg *cfg, char *clusterId);
+void    dnodeGetCfg(DnCfg *cfg, int32_t *dnodeId, char *clusterId);
+void    dnodeSetDropped(DnCfg *cfg);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /*_TD_DNODE_CFG_H_*/

source/server/dnode/src/dnodeCfg.c

+/*
+ * 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/>.
+ */
+
+#define _DEFAULT_SOURCE
+#include "os.h"
+#include "cJSON.h"
+#include "dnodeCfg.h"
+
+static int32_t dnodeReadCfg(DnCfg *cfg) {
+  int32_t len = 0;
+  int32_t maxLen = 200;
+  char *  content = calloc(1, maxLen + 1);
+  cJSON * root = NULL;
+  FILE *  fp = NULL;
+
+  fp = fopen(cfg->file, "r");
+  if (!fp) {
+    dDebug("file %s not exist", cfg->file);
+    goto PARSE_CFG_OVER;
+  }
+
+  len = (int32_t)fread(content, 1, maxLen, fp);
+  if (len <= 0) {
+    dError("failed to read %s since content is null", cfg->file);
+    goto PARSE_CFG_OVER;
+  }
+
+  content[len] = 0;
+  root = cJSON_Parse(content);
+  if (root == NULL) {
+    dError("failed to read %s since invalid json format", cfg->file);
+    goto PARSE_CFG_OVER;
+  }
+
+  cJSON *dnodeId = cJSON_GetObjectItem(root, "dnodeId");
+  if (!dnodeId || dnodeId->type != cJSON_Number) {
+    dError("failed to read %s since dnodeId not found", cfg->file);
+    goto PARSE_CFG_OVER;
+  }
+  cfg->dnodeId = (int32_t)dnodeId->valueint;
+
+  cJSON *dropped = cJSON_GetObjectItem(root, "dropped");
+  if (!dropped || dropped->type != cJSON_Number) {
+    dError("failed to read %s since dropped not found", cfg->file);
+    goto PARSE_CFG_OVER;
+  }
+  cfg->dropped = (int32_t)dropped->valueint;
+
+  cJSON *clusterId = cJSON_GetObjectItem(root, "clusterId");
+  if (!clusterId || clusterId->type != cJSON_String) {
+    dError("failed to read %s since clusterId not found", cfg->file);
+    goto PARSE_CFG_OVER;
+  }
+  tstrncpy(cfg->clusterId, clusterId->valuestring, TSDB_CLUSTER_ID_LEN);
+
+  dInfo("successed to read %s", cfg->file);
+
+PARSE_CFG_OVER:
+  if (content != NULL) free(content);
+  if (root != NULL) cJSON_Delete(root);
+  if (fp != NULL) fclose(fp);
+  terrno = 0;
+
+  return 0;
+}
+
+static int32_t dnodeWriteCfg(DnCfg *cfg) {
+  FILE *fp = fopen(cfg->file, "w");
+  if (!fp) {
+    dError("failed to write %s since %s", cfg->file, strerror(errno));
+    return -1;
+  }
+
+  int32_t len = 0;
+  int32_t maxLen = 200;
+  char *  content = calloc(1, maxLen + 1);
+
+  len += snprintf(content + len, maxLen - len, "{\n");
+  len += snprintf(content + len, maxLen - len, "  \"dnodeId\": %d,\n", cfg->dnodeId);
+  len += snprintf(content + len, maxLen - len, "  \"dropped\": %d,\n", cfg->dropped);
+  len += snprintf(content + len, maxLen - len, "  \"clusterId\": \"%s\"\n", cfg->clusterId);
+  len += snprintf(content + len, maxLen - len, "}\n");
+
+  fwrite(content, 1, len, fp);
+  taosFsync(fileno(fp));
+  fclose(fp);
+  free(content);
+  terrno = 0;
+
+  dInfo("successed to write %s", cfg->file);
+  return 0;
+}
+
+int32_t dnodeInitCfg(Dnode *dnode, DnCfg **out) {
+  DnCfg* cfg = calloc(1, sizeof(DnCfg));
+  if (cfg == NULL) return -1;
+
+  cfg->dnode = dnode;
+  cfg->dnodeId = 0;
+  cfg->dropped = 0;
+  cfg->clusterId[0] = 0;
+  snprintf(cfg->file, sizeof(cfg->file), "%s/dnodeCfg.json", tsDnodeDir);
+  pthread_mutex_init(&cfg->mutex, NULL);
+  *out = cfg;
+
+  int32_t ret = dnodeReadCfg(cfg);
+  if (ret == 0) {
+    dInfo("dnode cfg is initialized");
+  }
+
+  if (cfg->dropped) {
+    dInfo("dnode is dropped and start to exit");
+    return -1;
+  }
+
+  return ret;
+}
+
+void dnodeCleanupCfg(Dnode *dnode, DnCfg **out) {
+  DnCfg* cfg = *out;
+  *out = NULL;
+
+  pthread_mutex_destroy(&cfg->mutex);
+  free(cfg);
+}
+
+void dnodeUpdateCfg(DnCfg *cfg, SDnodeCfg *data) {
+  if (cfg == NULL || cfg->dnodeId == 0) return;
+
+  pthread_mutex_lock(&cfg->mutex);
+
+  cfg->dnodeId = data->dnodeId;
+  tstrncpy(cfg->clusterId, data->clusterId, TSDB_CLUSTER_ID_LEN);
+  dInfo("dnodeId is set to %d, clusterId is set to %s", cfg->dnodeId, cfg->clusterId);
+
+  dnodeWriteCfg(cfg);
+  pthread_mutex_unlock(&cfg->mutex);
+}
+
+void dnodeSetDropped(DnCfg *cfg) {
+  pthread_mutex_lock(&cfg->mutex);
+  cfg->dropped = 1;
+  dnodeWriteCfg(cfg);
+  pthread_mutex_unlock(&cfg->mutex);
+}
+
+int32_t dnodeGetDnodeId(DnCfg *cfg) {
+  int32_t dnodeId = 0;
+  pthread_mutex_lock(&cfg->mutex);
+  dnodeId = cfg->dnodeId;
+  pthread_mutex_unlock(&cfg->mutex);
+  return dnodeId;
+}
+
+void dnodeGetClusterId(DnCfg *cfg, char *clusterId) {
+  pthread_mutex_lock(&cfg->mutex);
+  tstrncpy(clusterId, cfg->clusterId, TSDB_CLUSTER_ID_LEN);
+  pthread_mutex_unlock(&cfg->mutex);
+}
+
+void dnodeGetCfg(DnCfg *cfg, int32_t *dnodeId, char *clusterId) {
+  pthread_mutex_lock(&cfg->mutex);
+  *dnodeId = cfg->dnodeId;
+  tstrncpy(clusterId, cfg->clusterId, TSDB_CLUSTER_ID_LEN);
+  pthread_mutex_unlock(&cfg->mutex);
+}