improve and add comments in examples/network/ including tcpserver.c

tcpclient.c udpserver.c and udpclient.c
Formatting
Co-authored-by: Man, Jianting (Meco) <[email protected]>

1 files changed, 20 insertions, 10 deletions

diff --git a/examples/network/udpserver.c b/examples/network/udpserver.c
index a33a27da10..33442a72ed 100644
--- a/examples/network/udpserver.c
+++ b/examples/network/udpserver.c
@@ -1,10 +1,11 @@
 /*
- * Copyright (c) 2006-2021, RT-Thread Development Team
+ * Copyright (c) 2006-2022, RT-Thread Development Team
  *
  * SPDX-License-Identifier: Apache-2.0
  *
  * Change Logs:
  * Date           Author       Notes
+ * 2022-01-24     ChungHsuan   improve code comments
  */
 
 #include <rtthread.h>
@@ -16,7 +17,7 @@
 #include <sys/time.h>
 #include <sys/select.h>
 #endif
-#include <sys/socket.h> /* 使用BSD socket，需要包含socket.h头文件 */
+#include <sys/socket.h> /* socket.h header file is needed when using BSD socket */ /* 使用BSD socket，需要包含socket.h头文件 */
 #include "netdb.h"
 
 #define DEBUG_UDP_SERVER
@@ -35,6 +36,9 @@ static int started = 0;
 static int is_running = 0;
 static int port = 5000;
 
+/**
+* @brief  This function is for creating a udp server on RT-Thread
+*/
 static void udpserv(void *paramemter)
 {
     int sock;
@@ -45,7 +49,7 @@ static void udpserv(void *paramemter)
 
     struct timeval timeout;
     fd_set readset;
-
+    /* Allocate space for recv_data */
     /* 分配接收用的数据缓冲 */
     recv_data = rt_malloc(BUFSZ);
     if (recv_data == RT_NULL)
@@ -53,20 +57,20 @@ static void udpserv(void *paramemter)
         LOG_E("No memory");
         return;
     }
-
+    /* Create a socket and set it to SOCK_DGRAM(UDP) */
     /* 创建一个socket，类型是SOCK_DGRAM，UDP类型 */
     if ((sock = socket(AF_INET, SOCK_DGRAM, 0)) == -1)
     {
         LOG_E("Create socket error");
         goto __exit;
     }
-
+    /* Initialize server side address */
     /* 初始化服务端地址 */
     server_addr.sin_family = AF_INET;
     server_addr.sin_port = htons(port);
     server_addr.sin_addr.s_addr = INADDR_ANY;
     rt_memset(&(server_addr.sin_zero), 0, sizeof(server_addr.sin_zero));
-
+    /* Bind socket to server side address */
     /* 绑定socket到服务端地址 */
     if (bind(sock, (struct sockaddr *)&server_addr,
              sizeof(struct sockaddr)) == -1)
@@ -92,7 +96,7 @@ static void udpserv(void *paramemter)
         /* Wait for read or write */
         if (select(sock + 1, &readset, RT_NULL, RT_NULL, &timeout) == 0)
             continue;
-
+        /* The maximum size received from sock is BUFSZ-1 bytes*/
         /* 从sock中收取最大BUFSZ - 1字节数据 */
         bytes_read = recvfrom(sock, recv_data, BUFSZ - 1, 0,
                               (struct sockaddr *)&client_addr, &addr_len);
@@ -108,11 +112,11 @@ static void udpserv(void *paramemter)
         }
         else
         {
-            recv_data[bytes_read] = '\0'; /* 把末端清零 */
-
+            recv_data[bytes_read] = '\0'; /* Append '\0' at the end of message *//* 把末端清零 */
+            /* Output received message */
             /* 输出接收的数据 */
             LOG_D("Received data = %s", recv_data);
-
+            /* If the message received is 'exit', quit. */
             /* 如果接收数据是exit，退出 */
             if (strcmp(recv_data, "exit") == 0)
             {
@@ -136,6 +140,9 @@ __exit:
     is_running = 0;
 }
 
+/**
+* @brief    The usage description of udp server on rt-Thread
+*/
 static void usage(void)
 {
     rt_kprintf("Usage: udpserver -p <port>\n");
@@ -148,6 +155,9 @@ static void usage(void)
     rt_kprintf("  --help       Print help information\n");
 }
 
+/**
+* @brief    This function is for testing udp server on rt-Thread
+*/
 static void udpserver_test(int argc, char** argv)
 {
     rt_thread_t tid;