improve plugin/node/group/tag storage

src/base/tag_table.c

@@ -0,0 +1,177 @@
+/**
+ * NEURON IIoT System for Industry 4.0
+ * Copyright (C) 2020-2021 EMQ Technologies Co., Ltd All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or (at your option) any later version.
+ *
+ * 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.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ **/
+
+#include <pthread.h>
+#include <stdlib.h>
+#include <sys/time.h>
+
+#include "utils/uthash.h"
+
+#include "tag_table.h"
+
+struct tag_elem {
+    neu_tag_t tag;
+
+    char           name[NEU_TAG_NAME_LEN];
+    UT_hash_handle hh;
+};
+
+struct neu_tag_table {
+    pthread_mutex_t mtx;
+    int64_t         timestamp;
+
+    struct tag_elem *tags;
+};
+
+static void update_timestamp(neu_tag_table_t *tbl)
+{
+    struct timeval tv = { 0 };
+
+    gettimeofday(&tv, NULL);
+
+    tbl->timestamp = tv.tv_sec * 1000 * 1000 + tv.tv_usec;
+}
+
+neu_tag_table_t *neu_tag_table_create(void)
+{
+    neu_tag_table_t *table = calloc(1, sizeof(neu_tag_table_t));
+
+    pthread_mutex_init(&table->mtx, NULL);
+
+    return table;
+}
+
+void neu_tag_table_destory(neu_tag_table_t *tbl)
+{
+    pthread_mutex_destroy(&tbl->mtx);
+
+    free(tbl);
+}
+
+uint32_t neu_tag_table_size(neu_tag_table_t *tbl)
+{
+    uint32_t size = 0;
+
+    pthread_mutex_lock(&tbl->mtx);
+    size = HASH_COUNT(tbl->tags);
+    pthread_mutex_unlock(&tbl->mtx);
+
+    return size;
+}
+
+neu_tag_t *neu_tag_table_get(neu_tag_table_t *tbl, const char *name)
+{
+    struct tag_elem *elem = NULL;
+    neu_tag_t *      tag  = NULL;
+
+    pthread_mutex_lock(&tbl->mtx);
+    HASH_FIND_STR(tbl->tags, name, elem);
+    if (elem != NULL) {
+        tag = calloc(1, sizeof(neu_tag_t));
+        memcpy(tag, &elem->tag, sizeof(neu_tag_t));
+    }
+    pthread_mutex_unlock(&tbl->mtx);
+
+    return tag;
+}
+
+int neu_tag_table_add(neu_tag_table_t *tbl, neu_tag_t *tag)
+{
+    int              ret  = -1;
+    struct tag_elem *elem = NULL;
+
+    pthread_mutex_lock(&tbl->mtx);
+    HASH_FIND_STR(tbl->tags, tag->name, elem);
+    if (elem == NULL) {
+        elem = calloc(1, sizeof(struct tag_elem));
+
+        elem->tag = *tag;
+        strncpy(elem->name, tag->name, strlen(tag->name));
+        HASH_ADD_STR(tbl->tags, name, elem);
+
+        update_timestamp(tbl);
+        ret = 0;
+    }
+    pthread_mutex_unlock(&tbl->mtx);
+
+    return ret;
+}
+
+int neu_tag_table_update(neu_tag_table_t *tbl, neu_tag_t *tag)
+{
+    int              ret  = -1;
+    struct tag_elem *elem = NULL;
+
+    pthread_mutex_lock(&tbl->mtx);
+    HASH_FIND_STR(tbl->tags, tag->name, elem);
+    if (elem != NULL) {
+        elem->tag = *tag;
+
+        update_timestamp(tbl);
+        ret = 0;
+    }
+    pthread_mutex_unlock(&tbl->mtx);
+
+    return ret;
+}
+
+int neu_tag_table_delete(neu_tag_table_t *tbl, const char *name)
+{
+    int              ret  = -1;
+    struct tag_elem *elem = NULL;
+
+    pthread_mutex_lock(&tbl->mtx);
+    HASH_FIND_STR(tbl->tags, name, elem);
+    if (elem != NULL) {
+        HASH_DEL(tbl->tags, elem);
+
+        update_timestamp(tbl);
+        ret = 0;
+    }
+    pthread_mutex_unlock(&tbl->mtx);
+
+    return ret;
+}
+void neu_tag_table_foreach(neu_tag_table_t *tbl, void *arg,
+                           neu_tag_table_foreach_fn fn)
+{
+    struct tag_elem *elem = NULL;
+
+    pthread_mutex_lock(&tbl->mtx);
+    for (elem = tbl->tags; elem != NULL; elem = elem->hh.next) {
+        fn(arg, &elem->tag);
+    }
+    pthread_mutex_unlock(&tbl->mtx);
+}
+
+int64_t neu_tag_table_change_foreach(neu_tag_table_t *tbl, int64_t timestamp,
+                                     void *arg, neu_tag_table_foreach_fn fn)
+{
+    struct tag_elem *elem = NULL;
+
+    pthread_mutex_lock(&tbl->mtx);
+    if (timestamp != tbl->timestamp) {
+        for (elem = tbl->tags; elem != NULL; elem = elem->hh.next) {
+            fn(arg, &elem->tag);
+        }
+    }
+    pthread_mutex_unlock(&tbl->mtx);
+
+    return tbl->timestamp;
+}