update socket server fork program, add convert lowercase to uppercase support

Guo Wenxue

2018-11-16 6c41fb183d2ea71bb8d3a7bf4947f28eacfe97fe

 ch3_fork/socket_server_fork.c

File was renamed from ch3_fork/socket_server.c
@@ -7,8 +7,7 @@
#include <arpa/inet.h>
#include <stdlib.h>
#include <getopt.h>

#define MSG_STR "Hello LingYun IoT Studio Client\n"
#include <ctype.h>

void print_usage(char *progname)
{
@@ -72,8 +71,8 @@
   memset(&servaddr, 0, sizeof(servaddr));
   servaddr.sin_family=AF_INET;
   servaddr.sin_port = htons(port);
   servaddr.sin_addr.s_addr = htonl(INADDR_ANY);
   //inet_aton("192.168.0.16", &servaddr.sin_addr);
   servaddr.sin_addr.s_addr = htonl(INADDR_ANY); /* listen all the IP address on this host */
   //inet_aton("192.168.0.16", &servaddr.sin_addr); /* Only listen specify IP address on this host */

   rv=bind(sockfd, (struct sockaddr *)&servaddr, sizeof(servaddr));
   if(rv < 0)
@@ -96,8 +95,7 @@
         continue;
      }

      printf("Accept new client[%s:%d] successfully\n", 
            inet_ntoa(cliaddr.sin_addr), ntohs(cliaddr.sin_port));
      printf("Accept new client[%s:%d] successfully\n", inet_ntoa(cliaddr.sin_addr), ntohs(cliaddr.sin_port));

      pid = fork();
      if( pid < 0 )
@@ -115,44 +113,50 @@
      else if ( 0 == pid )
      { 
         char                 buf[1024];
         int                  i;

         /* Child process close the listen socket fd */
         close(sockfd); 
		       
         printf("Child process start to commuicate with socket client...\n");
         memset(buf, 0, sizeof(buf));
                rv=read(clifd, buf, sizeof(buf));
                if( rv < 0)
                {
                   printf("Read data from client sockfd[%d] failure: %s\n", clifd, strerror(errno));
                   close(clifd);
            exit(0);
                }
                else if( rv == 0)
                { 
            printf("Socket[%d] get disconnected\n", clifd);
                   close(clifd);
            exit(0);
         } 
         else if( rv > 0 ) 

         close(sockfd); /* Child process close the listen socket fd */

         while(1)
         {
                   printf("Read %d bytes data from Server: %s\n", rv, buf);
                } 
			
         rv=write(clifd, MSG_STR, strlen(MSG_STR));
                if(rv < 0)
                {
                   printf("Write to client by sockfd[%d] failure: %s\n", clifd, strerror(errno));
                   close(clifd);
            exit(0);
                }
                   memset(buf, 0, sizeof(buf));
                   rv=read(clifd, buf, sizeof(buf));
                   if( rv < 0 )
                   {
                      printf("Read data from client sockfd[%d] failure: %s\n", clifd, strerror(errno));
                      close(clifd);
                      exit(0);
                   }
                   else if( rv == 0)
                   { 
               printf("Socket[%d] get disconnected\n", clifd);
                      close(clifd);
                      exit(0);
                   } 
            else if( rv > 0 ) 
            {
                      printf("Read %d bytes data from Server: %s\n", rv, buf);
                   } 

         sleep(1);
            /* convert letter from lowercase to uppercase */
            for(i=0; i<rv; i++)
            {
                      buf[i]=toupper(buf[i]);
            }

         printf("close client socket[%d] and child process exit\n", clifd);
                close(clifd);
                exit(0);
      }
            rv=write(clifd, buf, rv);
                   if(rv < 0)
                   {
                      printf("Write to client by sockfd[%d] failure: %s\n", clifd, strerror(errno));
                      close(clifd);
                      exit(0);
                   }

         } /* Child process loop */

      } /* Child process start*/
   }