[examples] update:

1. cleanup for posix dfs_net.
2. fixed recv buf overwrite.
3. format code.

examples/network/chargen.c

@@ -1,7 +1,14 @@
 #include <rtthread.h>
 #include <sys/socket.h>
-#include <sys/select.h>
+
+#ifdef RT_USING_DFS_NET
+#include <sys/select.h> // only dfs_net
 #include <dfs_posix.h>
+#else
+#define read        lwip_read
+#define write       lwip_write
+#endif /* RT_USING_DFS_NET */
+
 #include "netdb.h"
 
 #define MAX_SERV                 32         /* Maximum number of chargen services. Don't need too many */
@@ -61,7 +68,7 @@ static void chargen_thread(void *arg)
     /* Wait forever for network input: This could be connections or data */
     for (;;)
     {
-        maxfdp1 = listenfd+1;
+        maxfdp1 = listenfd + 1;
 
         /* Determine what sockets need to be in readset */
         FD_ZERO(&readset);
@@ -113,6 +120,7 @@ static void chargen_thread(void *arg)
                     closesocket(sock);
             }
         }
+
         /* Go through list of connected clients and process data */
         for (p_charcb = charcb_list; p_charcb; p_charcb = p_charcb->next)
         {
@@ -124,17 +132,19 @@ static void chargen_thread(void *arg)
                 if (do_read(p_charcb) < 0)
                     break;
             }
+
             if (FD_ISSET(p_charcb->socket, &writeset))
             {
                 char line[80];
                 char setchar = p_charcb->nextchar;
 
-                for( i = 0; i < 59; i++)
+                for (i = 0; i < 59; i++)
                 {
                     line[i] = setchar;
                     if (++setchar == 0x7f)
                         setchar = 0x21;
                 }
+
                 line[i] = 0;
                 strcat(line, "\n\r");
                 if (write(p_charcb->socket, line, strlen(line)) < 0)
@@ -142,6 +152,7 @@ static void chargen_thread(void *arg)
                     close_chargen(p_charcb);
                     break;
                 }
+
                 if (++p_charcb->nextchar == 0x7f)
                     p_charcb->nextchar = 0x21;
             }

examples/network/tcpclient.c

@@ -1,15 +1,12 @@
 #include <rtthread.h>
 
-//#include <lwip/netdb.h>   /* 为了解析主机名，需要包含netdb.h头文件 */
+#include <sys/socket.h> /* 使用BSD socket，需要包含socket.h头文件 */
-//#include <lwip/sockets.h> /* 使用BSD socket，需要包含sockets.h头文件 */
-
-#include <sys/socket.h> /* 使用BSD socket，需要包含sockets.h头文件 */
 #include "netdb.h"
 
 #define BUFSZ   1024
 
 static const char send_data[] = "This is TCP Client from RT-Thread."; /* 发送用到的数据 */
-void tcpclient(const char* url, int port)
+void tcpclient(const char *url, int port)
 {
     int ret;
     char *recv_data;
@@ -57,7 +54,7 @@ void tcpclient(const char* url, int port)
         return;
     }
 
-    while(1)
+    while (1)
     {
         /* 从sock连接中接收最大BUFSZ - 1字节数据 */
         bytes_received = recv(sock, recv_data, BUFSZ - 1, 0);
@@ -75,13 +72,14 @@ void tcpclient(const char* url, int port)
         {
             /* 打印recv函数返回值为0的警告信息 */
             rt_kprintf("\nReceived warning,recv function return 0.\r\n");
+
             continue;
         }
 
         /* 有接收到数据，把末端清零 */
         recv_data[bytes_received] = '\0';
 
-        if (strcmp(recv_data , "q") == 0 || strcmp(recv_data , "Q") == 0)
+        if (strcmp(recv_data, "q") == 0 || strcmp(recv_data, "Q") == 0)
         {
             /* 如果是首字母是q或Q，关闭这个连接 */
             closesocket(sock);
@@ -94,11 +92,11 @@ void tcpclient(const char* url, int port)
         else
         {
             /* 在控制终端显示收到的数据 */
-            rt_kprintf("\nReceived data = %s " , recv_data);
+            rt_kprintf("\nReceived data = %s ", recv_data);
         }
 
         /* 发送数据到sock连接 */
-        ret = send(sock,send_data,strlen(send_data), 0);
+        ret = send(sock, send_data, strlen(send_data), 0);
         if (ret < 0)
         {
             /* 接收失败，关闭这个连接 */

examples/network/tcpsendpacket.c

@@ -1,8 +1,9 @@
 #include <rtthread.h>
-#include <lwip/netdb.h>   /* 为了解析主机名，需要包含netdb.h头文件 */
-#include <lwip/sockets.h> /* 使用BSD socket，需要包含sockets.h头文件 */
 
-void tcp_senddata(const char* url, int port, int length)
+#include <netdb.h>   /* 为了解析主机名，需要包含netdb.h头文件 */
+#include <sys/socket.h> /* 使用BSD socket，需要包含socket.h头文件 */
+
+void tcp_senddata(const char *url, int port, int length)
 {
     struct hostent *host;
     int sock, err, result, timeout, index;
@@ -27,7 +28,7 @@ void tcp_senddata(const char* url, int port, int length)
 
     timeout = 100;
     /* 设置发送超时时间100ms */
-    lwip_setsockopt(sock, SOL_SOCKET, SO_SNDTIMEO, &timeout, sizeof(timeout));
+    setsockopt(sock, SOL_SOCKET, SO_SNDTIMEO, &timeout, sizeof(timeout));
     /* 初始化预连接的服务端地址 */
     server_addr.sin_family = AF_INET;
     server_addr.sin_port = htons(port);
@@ -38,20 +39,20 @@ void tcp_senddata(const char* url, int port, int length)
     err = connect(sock, (struct sockaddr *)&server_addr, sizeof(struct sockaddr));
     rt_kprintf("TCP thread connect error code: %d\n", err);
 
-    while(1)
+    while (1)
     {
         /* 发送数据到sock连接 */
         result = send(sock, buffer_ptr, length, MSG_DONTWAIT);
-        if(result < 0) //数据发送错误处理
+        if (result < 0) //数据发送错误处理
         {
             rt_kprintf("TCP thread send error: %d\n", result);
-            lwip_close(sock);
+            closesocket(sock);
 
             /* 关闭连接，重新创建连接 */
             rt_thread_delay(10);
 
             if ((sock = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) == -1)
-                rt_kprintf("TCP Socket error:%d\n",sock);
+                rt_kprintf("TCP Socket error:%d\n", sock);
 
             err = connect(sock, (struct sockaddr *)&server_addr, sizeof(struct sockaddr));
             rt_kprintf("TCP thread connect error code: %d\n", err);

examples/network/tcpserver.c

@@ -1,20 +1,21 @@
 #include <rtthread.h>
 
-//#include <lwip/sockets.h> /* 使用BSD Socket接口必须包含sockets.h这个头文件 */
+#include <sys/socket.h> /* 使用BSD socket，需要包含socket.h头文件 */
-#include <sys/socket.h> /* 使用BSD socket，需要包含sockets.h头文件 */
 #include "netdb.h"
 
+#define BUFSZ       (1024)
+
 static const char send_data[] = "This is TCP Server from RT-Thread."; /* 发送用到的数据 */
-void tcpserv(void* parameter)
+static void tcpserv(void *parameter)
 {
     char *recv_data; /* 用于接收的指针，后面会做一次动态分配以请求可用内存 */
-   rt_uint32_t sin_size;
+    socklen_t sin_size;
     int sock, connected, bytes_received;
     struct sockaddr_in server_addr, client_addr;
     rt_bool_t stop = RT_FALSE; /* 停止标志 */
     int ret;
 
-   recv_data = rt_malloc(1024); /* 分配接收用的数据缓冲 */
+    recv_data = rt_malloc(BUFSZ + 1); /* 分配接收用的数据缓冲 */
     if (recv_data == RT_NULL)
     {
         rt_kprintf("No memory\n");
@@ -36,7 +37,7 @@ void tcpserv(void* parameter)
     server_addr.sin_family = AF_INET;
     server_addr.sin_port = htons(5000); /* 服务端工作的端口 */
     server_addr.sin_addr.s_addr = INADDR_ANY;
-   rt_memset(&(server_addr.sin_zero),8, sizeof(server_addr.sin_zero));
+    rt_memset(&(server_addr.sin_zero), 0, sizeof(server_addr.sin_zero));
 
     /* 绑定socket到服务端地址 */
     if (bind(sock, (struct sockaddr *)&server_addr, sizeof(struct sockaddr)) == -1)
@@ -60,17 +61,22 @@ void tcpserv(void* parameter)
     }
 
     rt_kprintf("\nTCPServer Waiting for client on port 5000...\n");
-   while(stop != RT_TRUE)
+    while (stop != RT_TRUE)
     {
         sin_size = sizeof(struct sockaddr_in);
 
         /* 接受一个客户端连接socket的请求，这个函数调用是阻塞式的 */
         connected = accept(sock, (struct sockaddr *)&client_addr, &sin_size);
         /* 返回的是连接成功的socket */
+        if (connected < 0)
+        {
+            rt_kprintf("accept connection failed! errno = %d\n", errno);
+            continue;
+        }
 
         /* 接受返回的client_addr指向了客户端的地址信息 */
         rt_kprintf("I got a connection from (%s , %d)\n",
-                  inet_ntoa(client_addr.sin_addr),ntohs(client_addr.sin_port));
+                   inet_ntoa(client_addr.sin_addr), ntohs(client_addr.sin_port));
 
         /* 客户端连接的处理 */
         while (1)
@@ -91,7 +97,7 @@ void tcpserv(void* parameter)
             }
 
             /* 从connected socket中接收数据，接收buffer是1024大小，但并不一定能够收到1024大小的数据 */
-           bytes_received = recv(connected,recv_data, 1024, 0);
+            bytes_received = recv(connected, recv_data, BUFSZ, 0);
             if (bytes_received < 0)
             {
                 /* 接收失败，关闭这个connected socket */
@@ -102,12 +108,13 @@ void tcpserv(void* parameter)
             {
                 /* 打印recv函数返回值为0的警告信息 */
                 rt_kprintf("\nReceived warning,recv function return 0.\r\n");
-               continue;
+                closesocket(connected);
+                break;
             }
 
             /* 有接收到数据，把末端清零 */
             recv_data[bytes_received] = '\0';
-           if (strcmp(recv_data , "q") == 0 || strcmp(recv_data , "Q") == 0)
+            if (strcmp(recv_data, "q") == 0 || strcmp(recv_data, "Q") == 0)
             {
                 /* 如果是首字母是q或Q，关闭这个连接 */
                 closesocket(connected);
@@ -123,7 +130,7 @@ void tcpserv(void* parameter)
             else
             {
                 /* 在控制终端显示收到的数据 */
-               rt_kprintf("RECEIVED DATA = %s \n" , recv_data);
+                rt_kprintf("RECEIVED DATA = %s \n", recv_data);
             }
         }
     }

examples/network/udpclient.c

@@ -5,14 +5,14 @@
 #include "netdb.h"
 
 const char send_data[] = "This is UDP Client from RT-Thread.\n"; /* 发送用到的数据 */
-void udpclient(const char* url, int port, int count)
+void udpclient(const char *url, int port, int count)
 {
     int sock;
     struct hostent *host;
     struct sockaddr_in server_addr;
 
     /* 通过函数入口参数url获得host地址（如果是域名，会做域名解析） */
-   host= (struct hostent *) gethostbyname(url);
+    host = (struct hostent *) gethostbyname(url);
 
     /* 创建一个socket，类型是SOCK_DGRAM，UDP类型 */
     if ((sock = socket(AF_INET, SOCK_DGRAM, 0)) == -1)

examples/network/udpserver.c

@@ -1,17 +1,16 @@
 #include <rtthread.h>
-//#include <lwip/sockets.h> /* 使用BSD socket，需要包含sockets.h头文件 */
-#include <sys/socket.h> /* 使用BSD socket，需要包含sockets.h头文件 */
-#include "netdb.h"
 
+#include <sys/socket.h> /* 使用BSD socket，需要包含socket.h头文件 */
+#include "netdb.h"
 
 #define BUFSZ   1024
 
-void udpserv(void* paramemter)
+static void udpserv(void *paramemter)
 {
     int sock;
     int bytes_read;
     char *recv_data;
-   rt_uint32_t addr_len;
+    socklen_t addr_len;
     struct sockaddr_in server_addr, client_addr;
 
     /* 分配接收用的数据缓冲 */
@@ -37,10 +36,10 @@ void udpserv(void* paramemter)
     server_addr.sin_family = AF_INET;
     server_addr.sin_port = htons(5000);
     server_addr.sin_addr.s_addr = INADDR_ANY;
-   rt_memset(&(server_addr.sin_zero),0, sizeof(server_addr.sin_zero));
+    rt_memset(&(server_addr.sin_zero), 0, sizeof(server_addr.sin_zero));
 
     /* 绑定socket到服务端地址 */
-   if (bind(sock,(struct sockaddr *)&server_addr,
+    if (bind(sock, (struct sockaddr *)&server_addr,
              sizeof(struct sockaddr)) == -1)
     {
         /* 绑定地址失败 */
@@ -64,7 +63,7 @@ void udpserv(void* paramemter)
         recv_data[bytes_read] = '\0'; /* 把末端清零 */
 
         /* 输出接收的数据 */
-       rt_kprintf("\n(%s , %d) said : ",inet_ntoa(client_addr.sin_addr),
+        rt_kprintf("\n(%s , %d) said : ", inet_ntoa(client_addr.sin_addr),
                    ntohs(client_addr.sin_port));
         rt_kprintf("%s", recv_data);