fix: Multiple event data

Fix a regression introduced when adding the presence of topic in all
event data.

Author: euripedesrocha

Kconfig

@@ -177,4 +177,14 @@ menu "ESP-MQTT Configurations"
         help
             Messages which stays in the outbox longer than this value before being published will be discarded.
 
+    config MQTT_TOPIC_PRESENT_ALL_DATA_EVENTS
+        bool "Enable publish topic in all data events"
+        default n
+        depends on MQTT_USE_CUSTOM_CONFIG
+        help
+            Set to true to have publish topic in all data events. This changes the behaviour
+            when  the message is bigger than the receive buffer size. The first event of the sequence
+            always have the topic.
+            Note: This will allocate memory to store the topic only in case of messge bigger than the buffer size.
+
 endmenu

mqtt_client.c

@@ -1,5 +1,6 @@
 #include <stdint.h>
 #include <stdlib.h>
+#include <time.h>
 #include "esp_err.h"
 #include "esp_log.h"
 #include "esp_heap_caps.h"
@@ -1071,9 +1072,13 @@ static esp_err_t deliver_publish(esp_mqtt_client_handle_t client)
     uint8_t *msg_buf = client->mqtt_state.in_buffer;
     size_t msg_read_len = client->mqtt_state.in_buffer_read_len;
     size_t msg_total_len = client->mqtt_state.message_length;
-    size_t msg_topic_len = msg_read_len, msg_data_len = msg_read_len;
+    size_t msg_topic_len = msg_read_len;
+    size_t msg_data_len = msg_read_len;
     size_t msg_data_offset = 0;
-    char *msg_topic = NULL, *msg_data = NULL;
+    size_t saved_msg_topic_len = 0;
+    char *saved_msg_topic = NULL;
+    char *msg_topic = NULL;
+    char *msg_data = NULL;
 
     if (client->mqtt_state.connection.information.protocol_ver == MQTT_PROTOCOL_V_5) {
 #ifdef MQTT_PROTOCOL_5
@@ -1083,7 +1088,6 @@ static esp_err_t deliver_publish(esp_mqtt_client_handle_t client)
         }
 #endif
     } else {
-        // get and save topic
         msg_topic = mqtt_get_publish_topic(msg_buf, &msg_topic_len);
         if (msg_topic == NULL) {
             ESP_LOGE(TAG, "%s: mqtt_get_publish_topic() failed", __func__);
@@ -1098,11 +1102,7 @@ static esp_err_t deliver_publish(esp_mqtt_client_handle_t client)
             return ESP_FAIL;
         }
     }
-    char *saved_msg_topic = strndup(msg_topic, msg_topic_len);
-    ESP_MEM_CHECK(TAG, saved_msg_topic, return ESP_ERR_NO_MEM);
-    size_t saved_msg_topic_len = msg_topic_len;
 
-    // post data event
     client->event.retain = mqtt_get_retain(msg_buf);
     if (client->mqtt_state.connection.information.protocol_ver == MQTT_PROTOCOL_V_5) {
 #ifdef MQTT_PROTOCOL_5
@@ -1115,48 +1115,45 @@ static esp_err_t deliver_publish(esp_mqtt_client_handle_t client)
     client->event.dup = mqtt_get_dup(msg_buf);
     client->event.total_data_len = msg_data_len + msg_total_len - msg_read_len;
 
-    ESP_LOGD(TAG, "Get data len= %"NEWLIB_NANO_COMPAT_FORMAT", topic len=%"NEWLIB_NANO_COMPAT_FORMAT", total_data: %d offset: %"NEWLIB_NANO_COMPAT_FORMAT,
-             NEWLIB_NANO_COMPAT_CAST(msg_data_len), NEWLIB_NANO_COMPAT_CAST(msg_topic_len),
-             client->event.total_data_len, NEWLIB_NANO_COMPAT_CAST(msg_data_offset));
-    client->event.event_id = MQTT_EVENT_DATA;
-    client->event.data = msg_data_len > 0 ? msg_data : NULL;
-    client->event.data_len = msg_data_len;
-    client->event.current_data_offset = msg_data_offset;
-    client->event.topic = msg_topic;
-    client->event.topic_len = msg_topic_len;
-    esp_mqtt_dispatch_event(client);
-
-    client->event.topic = saved_msg_topic;
-    client->event.topic_len = saved_msg_topic_len;
-    while(msg_read_len < msg_total_len) {
-        size_t buf_len = client->mqtt_state.in_buffer_length;
-        msg_data = (char *)client->mqtt_state.in_buffer;
-        msg_data_offset += msg_data_len;
-
-        size_t read_len;
-        if(msg_total_len - msg_read_len > buf_len - saved_msg_topic_len) {
-            read_len = buf_len - saved_msg_topic_len;
-        } else {
-            read_len = msg_total_len - msg_read_len;
-        }
-
-        int ret = esp_transport_read(client->transport, (char *)client->mqtt_state.in_buffer, read_len, client->config->network_timeout_ms);
-        if (ret <= 0) {
-            return esp_mqtt_handle_transport_read_error(ret, client, false) == 0 ? ESP_OK : ESP_FAIL;
-        }
-
-        msg_data_len = ret;
-        msg_read_len += msg_data_len;
-
+    bool send_event = true;
+    while (send_event) {
         ESP_LOGD(TAG, "Get data len= %"NEWLIB_NANO_COMPAT_FORMAT", topic len=%"NEWLIB_NANO_COMPAT_FORMAT", total_data: %d offset: %"NEWLIB_NANO_COMPAT_FORMAT,
                  NEWLIB_NANO_COMPAT_CAST(msg_data_len), NEWLIB_NANO_COMPAT_CAST(msg_topic_len),
                  client->event.total_data_len, NEWLIB_NANO_COMPAT_CAST(msg_data_offset));
-
+        client->event.event_id = MQTT_EVENT_DATA;
+        client->event.data = msg_data_len > 0 ? msg_data : NULL;
         client->event.data_len = msg_data_len;
         client->event.current_data_offset = msg_data_offset;
-
+        client->event.topic = msg_topic;
+        client->event.topic_len = msg_topic_len;
         esp_mqtt_dispatch_event(client);
+        send_event = false;
+
+        if (msg_read_len < msg_total_len) {
+            send_event = true;
+            #ifdef CONFIG_MQTT_TOPIC_PRESENT_ALL_DATA_EVENTS
+            if (!saved_msg_topic) {
+                saved_msg_topic = strndup(msg_topic, msg_topic_len);
+                ESP_MEM_CHECK(TAG, saved_msg_topic, return ESP_ERR_NO_MEM);
+                saved_msg_topic_len = msg_topic_len;
+            }
+            #endif
+            size_t buf_len = client->mqtt_state.in_buffer_length;
+
+            msg_data = (char *)client->mqtt_state.in_buffer;
+            msg_topic = saved_msg_topic;
+            msg_topic_len = saved_msg_topic_len;
+            msg_data_offset += msg_data_len;
+            int ret = esp_transport_read(client->transport, (char *)client->mqtt_state.in_buffer,
+                                         msg_total_len - msg_read_len > buf_len ? buf_len : msg_total_len - msg_read_len,
+                                         client->config->network_timeout_ms);
+            if (ret <= 0) {
+                return esp_mqtt_handle_transport_read_error(ret, client, false) == 0 ? ESP_OK : ESP_FAIL;
+            }
 
+            msg_data_len = ret;
+            msg_read_len += msg_data_len;
+        }
     }
     free(saved_msg_topic);
     return ESP_OK;