perf: updated error checks

README.md

@@ -1,9 +1,5 @@
 # ESP32 ESP-IDF component for Syslog UDP client
 
-## SAST Tools
-
-[PVS-Studio](https://pvs-studio.com/pvs-studio/?utm_source=website&utm_medium=github&utm_campaign=open_source) — static analyzer for C, C++, C#, and Java code.
-
 ## Features
 
 1. Support for all standard syslog facility codes (0-23) per RFC 5424.
@@ -51,11 +47,11 @@ Messages are built using the format defined in [RFC 5424](https://datatracker.ie
 
 #define SYSLOG_IP "8.8.8.8"
 
-esp_timer_handle_t wifi_reconnect_timer = {0};
+esp_timer_handle_t wifi_reconnect_timer = NULL;
 uint8_t wifi_reconnect_retry_num = 0;
-EventGroupHandle_t event_group_handle = {0};
+EventGroupHandle_t event_group_handle = NULL;
 
-bool flag = false;
+volatile bool flag = false;
 
 void wifi_event_handler(void *arg, esp_event_base_t event_base, int32_t event_id, void *event_data);
 
@@ -75,8 +71,8 @@ void app_main(void)
     esp_wifi_set_config(WIFI_IF_STA, &wifi_config);
     esp_event_handler_instance_register(WIFI_EVENT, ESP_EVENT_ANY_ID, &wifi_event_handler, NULL, NULL);
     esp_event_handler_instance_register(IP_EVENT, IP_EVENT_STA_GOT_IP, &wifi_event_handler, NULL, NULL);
-    esp_wifi_start();
     event_group_handle = xEventGroupCreate();
+    esp_wifi_start();
     xEventGroupWaitBits(event_group_handle, WIFI_CONNECT_SUCCESS, pdTRUE, pdTRUE, portMAX_DELAY);
     zh_syslog_init_config_t config = ZH_SYSLOG_INIT_CONFIG_DEFAULT();
     strcpy(config.syslog_ip, SYSLOG_IP);
@@ -121,6 +117,7 @@ void wifi_event_handler(void *arg, esp_event_base_t event_base, int32_t event_id
             {
                 esp_timer_stop(wifi_reconnect_timer);
                 esp_timer_delete(wifi_reconnect_timer);
+                wifi_reconnect_timer = NULL;
             }
             esp_timer_create_args_t wifi_reconnect_timer_args = {
                 .callback = (void *)esp_wifi_connect,

include/zh_syslog.h

@@ -10,8 +10,8 @@
  * - Support for all standard syslog facility codes (0-23)
  * - Support for all standard syslog severity levels (0-7)
  * - RFC 5424 format message generation
- * - Thread-safe initialization and deinitialization
- * - MALLOC_CAP_8BIT memory allocation for DMA compatibility
+ * - Short messages are formatted into a stack buffer, longer ones fall back
+ *   to a heap allocation with the exact required size
  *
  * @note Connection to the network must be established before calling zh_syslog_init().
  * @warning This library does not guarantee message delivery (UDP is connectionless).
@@ -19,17 +19,15 @@
 
 #pragma once
 
+#include "stdio.h"
+#include "string.h"
+#include "stdint.h"
 #include "stdbool.h"
+#include "esp_heap_caps.h"
 #include "esp_err.h"
 #include "esp_log.h"
-#include "lwip/err.h"
 #include "lwip/sockets.h"
-#include "lwip/sys.h"
-#include "lwip/netdb.h"
 
-/**
- * @brief Default syslog client initialization configuration.
- */
 #define ZH_SYSLOG_INIT_CONFIG_DEFAULT() \
     {                                   \
         .syslog_ip = "192.168.0.1",     \
@@ -116,10 +114,11 @@ extern "C"
      * Creates a UDP socket and configures connection parameters
      * for the remote syslog server.
      *
-     * @param[in] config Pointer to syslog client initialization configuration structure. Can point to a temporary variable (must not be NULL)
+     * @param[in] config Pointer to syslog client initialization configuration structure (must not be NULL)
      *
      * @return ESP_OK on success
-     * @return ESP_ERR_INVALID_ARG if config is NULL
+     * @return ESP_ERR_INVALID_ARG if any parameter is NULL, port is out of range, or IP is malformed
+     * @return ESP_ERR_INVALID_STATE if client is already initialized
      * @return ESP_FAIL if socket creation fails
      *
      * @note Connection to the network must be established before calling this function.
@@ -147,12 +146,12 @@ extern "C"
      *
      * @param[in] facility Syslog facility code (0-23)
      * @param[in] severity Syslog severity code (0-7)
-     * @param[in] hostname Pointer to device hostname that generated the message. Only alphanumeric characters without spaces (must not be NULL)
-     * @param[in] app_name Pointer to application name that generated the message. Only alphanumeric characters without spaces (must not be NULL)
+     * @param[in] hostname Pointer to device hostname that generated the message (must not be NULL)
+     * @param[in] app_name Pointer to application name that generated the message (must not be NULL)
      * @param[in] message Pointer to the message payload to send (must not be NULL)
      *
      * @return ESP_OK on success
-     * @return ESP_ERR_INVALID_ARG if hostname, app_name, or message is NULL
+     * @return ESP_ERR_INVALID_ARG if hostname, app_name, or message is NULL, or facility/severity is out of range
      * @return ESP_ERR_INVALID_STATE if zh_syslog_init() was not called previously
      * @return ESP_ERR_NO_MEM if memory allocation fails
      * @return ESP_FAIL if UDP send operation fails

zh_syslog.c

@@ -13,19 +13,22 @@
 
 static const char *TAG = "zh_syslog";
 
-static zh_syslog_init_config_t _init_config = {0}; /*!< Syslog client initialization configuration (internal copy) */
-static struct sockaddr_in _syslog_server = {0};    /*!< Pre-configured syslog server address */
-volatile static int _socket = 0;                   /*!< UDP socket file descriptor */
-volatile static bool _is_initialized = false;      /*!< Initialization status flag */
+static struct sockaddr_in _syslog_server = {0};
+volatile static int _socket = -1;
+volatile static bool _is_initialized = false;
 
 esp_err_t zh_syslog_init(const zh_syslog_init_config_t *config)
 {
     ESP_LOGI(TAG, "Syslog client initialization begin.");
     ZH_ERROR_CHECK(config != NULL, ESP_ERR_INVALID_ARG, NULL, "Syslog client initialization fail. Invalid argument.");
-    _init_config = *config;
-    _syslog_server.sin_addr.s_addr = inet_addr(_init_config.syslog_ip);
+    ZH_ERROR_CHECK(_is_initialized == false, ESP_ERR_INVALID_STATE, NULL, "Syslog client initialization fail. Syslog client already initialized.");
+    ZH_ERROR_CHECK(config->syslog_port != 0 && config->syslog_port <= 65535, ESP_ERR_INVALID_ARG, NULL, "Syslog client initialization fail. Invalid argument.");
+    ZH_ERROR_CHECK(memchr(config->syslog_ip, '\0', sizeof(config->syslog_ip)) != NULL, ESP_ERR_INVALID_ARG, NULL, "Syslog client initialization fail. Invalid IP.");
+    struct in_addr addr;
+    ZH_ERROR_CHECK(inet_pton(AF_INET, config->syslog_ip, &addr) == 1, ESP_ERR_INVALID_ARG, NULL, "Syslog client initialization fail. Invalid argument.");
+    _syslog_server.sin_addr = addr;
     _syslog_server.sin_family = AF_INET;
-    _syslog_server.sin_port = htons(_init_config.syslog_port);
+    _syslog_server.sin_port = htons((uint16_t)config->syslog_port);
     _socket = socket(AF_INET, SOCK_DGRAM, 0);
     ZH_ERROR_CHECK(_socket >= 0, ESP_FAIL, NULL, "Syslog client initialization fail. Create socket error.");
     _is_initialized = true;
@@ -37,24 +40,39 @@ esp_err_t zh_syslog_deinit(void)
 {
     ESP_LOGI(TAG, "Syslog client deinitialization begin.");
     ZH_ERROR_CHECK(_is_initialized == true, ESP_ERR_INVALID_STATE, NULL, "Syslog client deinitialization fail. Syslog client not initialized.");
-    shutdown(_socket, 0);
     close(_socket);
+    _socket = -1;
     _is_initialized = false;
     ESP_LOGI(TAG, "Syslog client deinitialization success.");
     return ESP_OK;
 }
 
-esp_err_t zh_syslog_send(const zh_syslog_facility_code_t facility, const zh_syslog_severity_code_t severity, const char *hostname, const char *app_name, const char *message) // -V2008
+esp_err_t zh_syslog_send(const zh_syslog_facility_code_t facility, const zh_syslog_severity_code_t severity, const char *hostname, const char *app_name, const char *message)
 {
     ESP_LOGI(TAG, "Syslog client send begin.");
     ZH_ERROR_CHECK(hostname != NULL && app_name != NULL && message != NULL, ESP_ERR_INVALID_ARG, NULL, "Syslog client send fail. Invalid argument.");
     ZH_ERROR_CHECK(_is_initialized == true, ESP_ERR_INVALID_STATE, NULL, "Syslog client send fail. Syslog client not initialized.");
-    char *payload = heap_caps_calloc(1, 1024, MALLOC_CAP_8BIT);
+    ZH_ERROR_CHECK(facility >= ZH_KERN && facility <= ZH_LOCAL7 && severity >= ZH_EMERG && severity <= ZH_DEBUG, ESP_ERR_INVALID_ARG, NULL, "Syslog client send fail. Invalid argument.");
+    const int pri = ((uint8_t)facility * 8) + (uint8_t)severity;
+    char stack_buf[256];
+    int len = snprintf(stack_buf, sizeof(stack_buf), "<%d>1 - %s %s - - - %s", pri, hostname, app_name, message);
+    ZH_ERROR_CHECK(len >= 0, ESP_FAIL, NULL, "Syslog client send fail. Format error.");
+    char *payload = stack_buf;
+    bool heap_allocated = false;
+    if (len >= sizeof(stack_buf))
+    {
+        payload = heap_caps_calloc(1, len + 1, MALLOC_CAP_8BIT);
         ZH_ERROR_CHECK(payload != NULL, ESP_ERR_NO_MEM, NULL, "Syslog client send fail. Memory allocation fail or no free memory in the heap.");
-    sprintf(payload, "<%d>1 - %s %s - - - %s", ((uint8_t)facility * 8) + (uint8_t)severity, hostname, app_name, message);
-    int temp = sendto(_socket, payload, strlen(payload), 0, (struct sockaddr *)&_syslog_server, sizeof(_syslog_server)); // -V641
-    ZH_ERROR_CHECK(temp >= 0, ESP_FAIL, heap_caps_free(payload), "Syslog client send fail. Socket error.");
+        int written = snprintf(payload, len + 1, "<%d>1 - %s %s - - - %s", pri, hostname, app_name, message);
+        ZH_ERROR_CHECK(written == len, ESP_FAIL, heap_caps_free(payload), "Syslog client send fail. Format error.");
+        heap_allocated = true;
+    }
+    int sent = sendto(_socket, payload, len, 0, (struct sockaddr *)&_syslog_server, sizeof(_syslog_server));
+    if (heap_allocated == true)
+    {
         heap_caps_free(payload);
+    }
+    ZH_ERROR_CHECK(sent == len, ESP_FAIL, NULL, "Syslog client send fail. Socket error.");
     ESP_LOGI(TAG, "Syslog client send success.");
     return ESP_OK;
 }