From 8cf9ba95f857cbbc7f5d49b631075884a98e260b Mon Sep 17 00:00:00 2001
From: gc87 <sfme@qq.com>
Date: Fri, 29 Jul 2022 15:47:12 +0800
Subject: [PATCH] refactor(mqtt): static alloc -> dynamic alloc

---
 plugins/mqtt/mqtt_plugin.c     | 11 ++++++++---
 src/connection/mqtt_c_client.c | 26 ++++++++++++++++++++------
 2 files changed, 28 insertions(+), 9 deletions(-)

diff --git a/plugins/mqtt/mqtt_plugin.c b/plugins/mqtt/mqtt_plugin.c
index c22990a4..ed843d0c 100644
--- a/plugins/mqtt/mqtt_plugin.c
+++ b/plugins/mqtt/mqtt_plugin.c
@@ -28,6 +28,7 @@
 
 #define INTERVAL 100000U
 #define TIMEOUT 3000U
+#define MAX_TOPIC_LEN 256
 
 #define TOPIC_READ_REQ "neuron/%s/read/req"
 #define TOPIC_WRITE_REQ "neuron/%s/write/req"
@@ -64,13 +65,17 @@ struct mqtt_routine {
 
 static char *topics_format(char *format, char *name)
 {
-    char temp[256] = { '\0' };
-    int  rc        = snprintf(temp, 256, format, name);
+    char *topic = calloc(1, MAX_TOPIC_LEN);
+    if (NULL == topic) {
+        return NULL;
+    }
+
+    int rc = snprintf(topic, MAX_TOPIC_LEN, format, name);
     if (-1 != rc) {
-        char *topic = strdup(temp);
         return topic;
     }
 
+    free(topic);
     return NULL;
 }
 
diff --git a/src/connection/mqtt_c_client.c b/src/connection/mqtt_c_client.c
index 11fdb092..964e0ce0 100644
--- a/src/connection/mqtt_c_client.c
+++ b/src/connection/mqtt_c_client.c
@@ -53,8 +53,8 @@ struct reconnect_state {
     char *           key_file;
     char *           keypass;
     mqtt_c_client_t *client;
-    uint8_t          send_buf[SEND_BUF_SIZE];
-    uint8_t          recv_buf[RECV_BUF_SIZE];
+    uint8_t *        send_buf;
+    uint8_t *        recv_buf;
     size_t           send_buf_sz;
     size_t           recv_buf_sz;
     X509 *           cert;
@@ -410,6 +410,14 @@ static void reconnect_state_uninit(struct reconnect_state *state)
     if (NULL != state->keypass) {
         free(state->keypass);
     }
+
+    if (NULL != state->send_buf) {
+        free(state->send_buf);
+    }
+
+    if (NULL != state->recv_buf) {
+        free(state->recv_buf);
+    }
 }
 
 static void subscribe_on_reconnect(mqtt_c_client_t *client)
@@ -584,6 +592,14 @@ static mqtt_c_client_t *client_create(const neu_mqtt_option_t *option,
         return NULL;
     }
 
+    struct reconnect_state *state = &client->state;
+    state->send_buf               = calloc(1, SEND_BUF_SIZE);
+    state->recv_buf               = calloc(1, RECV_BUF_SIZE);
+    if (NULL == state->send_buf || NULL == state->recv_buf) {
+        zlog_error(option->log, "mqtt buff alloc error");
+        return NULL;
+    }
+
     client->option            = option;
     client->user_data         = context;
     client->state_update_func = client->option->state_update_func;
@@ -591,8 +607,6 @@ static mqtt_c_client_t *client_create(const neu_mqtt_option_t *option,
     UT_icd tuple_icd = { sizeof(struct subscribe_tuple *), NULL, NULL, NULL };
     utarray_new(client->array, &tuple_icd);
 
-    struct reconnect_state *state = &client->state;
-
     if (NULL != client->option->clientid) {
         state->client_id = strdup(client->option->clientid);
     }
@@ -644,8 +658,8 @@ static mqtt_c_client_t *client_create(const neu_mqtt_option_t *option,
     }
 
     state->client      = client;
-    state->send_buf_sz = sizeof(state->send_buf);
-    state->recv_buf_sz = sizeof(state->recv_buf);
+    state->send_buf_sz = SEND_BUF_SIZE;
+    state->recv_buf_sz = RECV_BUF_SIZE;
     state->cert        = NULL;
     state->key         = NULL;
     state->ssl_ctx     = NULL;