C服务器和Java客户端之间的UDP连接
我还有一个问题:)我有一个简单的C语言UDP服务器,它读取一些字节,对这些字节进行解码,当它有一个C语言的字符串时,它会通过UDP发送到另一个C语言的服务器。这是我的C服务器的代码,名为preprocessamiento。我很快就发布了整个过程,但也许这已经完成了与我的问题无关C服务器和Java客户端之间的UDP连接,java,c++,c,udp,client-server,Java,C++,C,Udp,Client Server,我还有一个问题:)我有一个简单的C语言UDP服务器,它读取一些字节,对这些字节进行解码,当它有一个C语言的字符串时,它会通过UDP发送到另一个C语言的服务器。这是我的C服务器的代码,名为preprocessamiento。我很快就发布了整个过程,但也许这已经完成了与我的问题无关 #include <sys/types.h> #include <sys/socket.h> #include <netdb.h> #include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <math.h>
#include <stdint.h>
#include <string.h>
#include <openssl/sha.h>
#include <openssl/hmac.h>
#include <openssl/evp.h>
#include <openssl/bio.h>
#include <openssl/buffer.h>
#define MAXBUF 512
#define SENDING 0x52
#define RESIVING 0xB4
#define TYPE 0xA3F0
int createSocket();
char *unbase64(unsigned char *input, int length);
/* This function recives bytes(ASCII numbers) and returns the char */
void cambiarAChars(char* bytes, char* result)
{
unsigned int ch;
char a[4];
char buff[50];
strcpy(result,"");
int i=0;
while(i<strlen(bytes))
{
if(bytes[i]=='1')
{
a[0]=bytes[i];
a[1]=bytes[i+1];
a[2]=bytes[i+2];
a[3]='\0';
i=i+3;
}
else
{
a[0]=bytes[i];
a[1]=bytes[i+1];
a[2]='\0';
i=i+2;
}
ch = atoi(a);
sprintf(buff,"%c",ch);
strcat(result,buff);
}
}
/*this is the message that is going to be sent to the other server*/
char msg[MAXBUF];
/*this is the bytes recived*/
char bytes[MAXBUF];
void loadConfig(struct sockaddr_in *udpServer,struct sockaddr_in *thisServer,unsigned char *file);
int sendDataToServerXX(struct sockaddr_in *udpServer, int udpSocket);
int *useStdrr;
int *maxRequests;
int returnStatus;
int main(int argc, char* argv[])
{
if (argc < 2)
{
fprintf(stderr, "Usage: %s <file.config adress>\n", argv[0]);
exit(1);
}
useStdrr=malloc(sizeof(int));
maxRequests=malloc(sizeof(int));
struct sockaddr_in udpServer,thisServer,udpClient;
loadConfig(&udpServer,&thisServer, argv[1]);
int thisServerSocket = createSocket();
int udpSocket=createSocket();
int addrlen;
printf("Listening on.. %d \n",thisServer.sin_port);
thisServer.sin_family = AF_INET;
returnStatus = bind(thisServerSocket, (struct sockaddr*)&thisServer, sizeof(thisServer));
if (returnStatus == 0) {
fprintf(stderr, "Bind completed!\n");
}
else {
fprintf(stderr, "Could not bind to address \n" );
close(thisServerSocket);
exit(1);
}
/*En este while infinito estamos esperando los datos de las tramas*/
while (1)
{
addrlen = sizeof(udpClient);
/* How to resive a struct? */
returnStatus = recvfrom(thisServerSocket,(char*)&bytes, sizeof(bytes), 0,
(struct sockaddr*)&udpClient, &addrlen);
if (returnStatus == -1) {
fprintf(stderr, "Could not receive message!\n");
}
else {
printf("Lo que llego: %s \n",bytes);
/*Primero quitamos el 0 y 1 y guardamos el nuevo arreglo en p*/
bytes[strlen(bytes)-1]='\0';
char p[strlen(bytes)];
int i=0;
while(bytes[i+1]!='\0'){
p[i]=bytes[i+1];
i++;
}
/*esto simula la cambiada a base10 de base64*/
char *result=malloc(512);
char *p2=malloc(sizeof(p)+1);
strcpy(p2,p);
cambiarAChars(p2,result);
strcat(result,"\n\0");
printf("TAMANO: %d \n",strlen(result));
char *output = unbase64(result, strlen(result));
printf("Unbase64: %s\n", output);
msg[0]='%';
strcat(msg,output);
int f=strlen(msg);
msg[f]='%';
msg[f+1]='\0';
printf("Voy a mandar: %s \n",msg);
sendDataToServerXX(&udpServer,udpSocket);
free(output);
}
}
close(thisServerSocket);
close(udpSocket);
}
int createSocket()
{
/* create a socket */
int Socket;
Socket = socket(AF_INET, SOCK_DGRAM, 0);
if (Socket == -1)
{
if(*useStdrr)
{
fprintf(stderr, "Could not create a socket!\n");
}
exit(1);
}
else {
printf("Socket created.\n");
}
return Socket;
}
void loadConfig(struct sockaddr_in *udpServer,struct sockaddr_in *thisServer, unsigned char *file)
{
char line[256];
int linenum=0;
FILE* f = fopen(file, "r");
while(fgets(line, 256, f) != NULL)
{
char atribute[256], value[256];
linenum++;
if(line[0] == '#'||line[0] == ' ') {
continue;
}
else{
if(sscanf(line, "%s %s", atribute, value) != 2)
{
fprintf(stderr, "Syntax error, line %d\n", linenum);
continue;
}
if(!strcmp(atribute,"server_address" ))
{
if(!strcmp(value,""))
{
udpServer->sin_addr.s_addr = htonl(INADDR_ANY);
}
else{
udpServer->sin_addr.s_addr = inet_addr(value);
}
}
else if(!strcmp(atribute,"server_port"))
{
udpServer->sin_port = htons(atoi(value));
}
else if(!strcmp(atribute,"print_message_details"))
{
if(!strcmp(value,"ON"))
{
*useStdrr=1;
}
else
{
*useStdrr=0;
}
}
else if(!strcmp(atribute,"request_count"))
{
*maxRequests=5;
}
else if(!strcmp(atribute,"valor_que_viene_del_cohete_simulado"))
{
}
else if(!strcmp(atribute,"this_server_address"))
{
if(!strcmp(value,""))
{
thisServer->sin_addr.s_addr = htonl(INADDR_ANY);
}
else{
thisServer->sin_addr.s_addr = inet_addr(value);
}
}
else if(!strcmp(atribute,"this_server_port"))
{
thisServer->sin_port = htons(atoi(value));
}
}
}
}
int sendDataToServerXX(struct sockaddr_in *udpServer, int udpSocket)
{
udpServer->sin_family = AF_INET;
int in=0;
int boolv=0;
while(in<*maxRequests)
{
in++;
returnStatus = sendto(udpSocket,(char*) &msg, sizeof(msg), 0,
(struct sockaddr*)udpServer, sizeof(*udpServer));
if (returnStatus == -1) {
if(*useStdrr)
{
fprintf(stderr, "Could not send message!\n");
}
}
else {
printf("Datos enviados al servidor xx.\n");
memset(msg, 0, strlen(msg));
in=*maxRequests;
boolv=1;
}
}
if(!boolv)
{
if(*useStdrr)
{
fprintf(stderr, "fixed number of requests finished.. no reply.\n");
}
}
return 0;
}
char *unbase64(unsigned char *input, int length)
{
BIO *b64, *bmem;
char *buffer = (char *)malloc(length);
memset(buffer, 0, length);
b64 = BIO_new(BIO_f_base64());
BIO_set_flags(b64, BIO_FLAGS_BASE64_NO_NL);
bmem = BIO_new_mem_buf(input, length);
bmem = BIO_push(b64, bmem);
BIO_read(bmem, buffer, length);
BIO_free_all(bmem);
return buffer;
}
#包括
#包括
#包括
#包括
#包括
#包括
#包括
#包括
#包括
#包括
#包括
#包括
#包括
#包括
#包括
#定义MAXBUF 512
#定义发送0x52
#定义调整大小0xB4
#定义类型0xA3F0
int createSocket();
字符*unbase64(无符号字符*输入,整数长度);
/*此函数接收字节(ASCII数字)并返回字符*/
void cambiarAChars(字符*字节,字符*结果)
{
无符号int-ch;
chara[4];
字符buff[50];
strcpy(结果“”);
int i=0;
而(isin_addr.s_addr=htonl(INADDR_ANY);
}
否则{
udpServer->sin\u addr.s\u addr=inet\u addr(值);
}
}
如果(!strcmp(atribute,“服务器端口”))
{
udpServer->sin_port=htons(atoi(值));
}
否则,如果(!strcmp(atribute,“打印消息详细信息”))
{
如果(!strcmp(值,“开”))
{
*useStdrr=1;
}
其他的
{
*useStdrr=0;
}
}
否则,如果(!strcmp(atribute,“请求计数”))
{
*最大请求数=5;
}
否则,如果(!strcmp(atribute,“valor_que_viene_del_cohete_simulado”))
{
}
如果(!strcmp(atribute,“此服务器地址”))
{
如果(!strcmp(值,“”)
{
此服务器->sin\u addr.s\u addr=htonl(INADDR\u ANY);
}
否则{
thisServer->sin\u addr.s\u addr=inet\u addr(值);
}
}
如果(!strcmp(atribute,“此服务器端口”))
{
thisServer->sin_port=htons(atoi(value));
}
}
}
}
int-sendDataToServerXX(在*udpServer中的结构sockaddr_,int-udpSocket)
{
udpServer->sin_family=AF_INET;
int in=0;
int boolv=0;
while(insin_addr.s_addr=inet_addr(值);
}
}
如果(!strcmp(atribute,“服务器端口”))
{
udpServer->sin_port=htons(atoi(值));
}
否则,如果(!strcmp(atribute,“打印消息详细信息”))
{
如果(!strcmp(值,“开”))
{
*useStdrr=1;
}
其他的
{
*useStdrr=0;
}
}
否则,如果(!strcmp(atribute,“请求计数”))
{
*maxRequests=atoi(值);
}
否则如果(!strcmp(atribute,“请求超时”))
{
*超时=atoi(值);
}
}
}
}
现在真正的问题是:从java客户端到C服务器的C连接是否需要与连接到另一个C客户端不同?如果答案是否定的,那么问题出在java项目中?他们告诉我它工作正常,但我认为他们已经用java服务器对其进行了测试。有什么不同吗?如果问题是在java项目中,我应该告诉他们如何更改以使其与我的C服务器一起工作
很多thx
Alejandro Casas没有UDP连接。在UDP中,程序只是在给定IP的给定端口上抛出数据包。如果在该IP/端口上没有任何内容侦听,或者接收程序决定忽略UDP数据包,则会丢弃该数据包。如果需要实际连接,则使用TCP 此外,某些ISP默认情况下会阻止某些类型的UDP数据包 在Java中,TCP套接字称为套接字,UDP套接字称为DatagramSocket。请确保您是从Java客户端上的DatagramSocket发送的 不过我还没有用C做过套接字编程
最后,如果您发布一些Java代码,这会有所帮助。这是一个关于如何开始开发Java客户机/服务器的好例子。 请注意,它来自Kurose和Ross的“计算机网络:自上而下的方法” 这本书在JAVA中有两个UDP/TCP示例,非常好,我向您推荐 UDP服务器/客户端: TCP服务器/客户端:
如果Java服务器通过网络堆栈发送UDP,那么您应该能够使用任何语言编写的UDP客户端来接收数据。您是否使用wireshark之类的工具来验证数据包是否来自Java服务器?@Alejandro,如果您不打算花时间清理源代码,那么很难期望其他人会这样做r用户可以利用他们宝贵的时间免费帮助您。。。
#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <string.h>
#define MAXBUF 1024
#define SENDING 0x52
#define RESIVING 0xB4
#define TYPE 0xA3F0
int createSocket();
char msg[MAXBUF];
void loadConfig(struct sockaddr_in *udpServer, char *file);
int *useStdrr;
int *maxRequests;
int *timeOut;
int main(int argc, char* argv[])
{
int returnStatus;
int addrlen;
struct sockaddr_in udpClient, udpServer;
char buf[MAXBUF];
useStdrr=malloc(sizeof(int));
maxRequests=malloc(sizeof(int));
timeOut=malloc(sizeof(int));
/*ms.timezone="AES";*/
if (argc < 2)
{
fprintf(stderr, "Usage: %s <file.config adress>\n", argv[0]);
exit(1);
}
int udpSocket=createSocket();
udpServer.sin_family = AF_INET;
loadConfig(&udpServer, argv[1]);
/*how to send a struct here?*/
int in=0;
int boolv=0;
printf("Request number %i\n",*maxRequests);
while(in<*maxRequests)
{
in++;
printf("Request number %i\n",in);
printf("Adresss::: %d\n",udpServer.sin_addr.s_addr);
printf("PORT:::: %i\n",udpServer.sin_port);
returnStatus = sendto(udpSocket,(char*) &msg, sizeof(msg), 0,
(struct sockaddr*)&udpServer, sizeof(udpServer));
if (returnStatus == -1) {
if(*useStdrr)
{
fprintf(stderr, "Could not send message!\n");
}
}
else {
printf("Message sent.\n");
/* message sent: look for confirmation */
/*
addrlen = sizeof(udpServer);
returnStatus = recvfrom(udpSocket, (char*) &msg, sizeof(msg), 0,
(struct sockaddr*)&udpServer, &addrlen);
if (returnStatus == -1) {
if(*useStdrr)
{
fprintf(stderr, "Did not receive confirmation!\n");
}
}
else {
printf("Second: %s\n", msg);
*/
in=*maxRequests;
boolv=1;
/*
}*/
}
}
if(!boolv)
{
if(*useStdrr)
{
fprintf(stderr, "fixed number of requests finished.. no reply.\n");
}
}
close(udpSocket);
return 0;
}
int createSocket()
{
/* create a socket */
int Socket;
Socket = socket(AF_INET, SOCK_DGRAM, 0);
if (Socket == -1)
{
if(*useStdrr)
{
fprintf(stderr, "Could not create a socket!\n");
}
exit(1);
}
else {
printf("Socket created.\n");
}
return Socket;
}
void loadConfig(struct sockaddr_in *udpServer, char *file)
{
char line[256];
int linenum=0;
FILE* f = fopen(file, "r");
while(fgets(line, 256, f) != NULL)
{
char atribute[256], value[256];
linenum++;
if(line[0] == '#'||line[0] == ' ') {
continue;
}
else{
if(sscanf(line, "%s %s", atribute, value) != 2)
{
fprintf(stderr, "Syntax error, line %d\n", linenum);
continue;
}
printf("Atribute: %s\n",atribute);
printf("Value: %s\n",value);
if(!strcmp(atribute,"server_address" ))
{
if(!strcmp(value,""))
{
udpServer->sin_addr.s_addr = htonl(INADDR_ANY);
}
else{
udpServer->sin_addr.s_addr = inet_addr(value);
}
}
else if(!strcmp(atribute,"server_port"))
{
udpServer->sin_port = htons(atoi(value));
}
else if(!strcmp(atribute,"print_message_details"))
{
if(!strcmp(value,"ON"))
{
*useStdrr=1;
}
else
{
*useStdrr=0;
}
}
else if(!strcmp(atribute,"request_count"))
{
*maxRequests=atoi(value);
}
else if(!strcmp(atribute,"request_*timeOut"))
{
*timeOut=atoi(value);
}
}
}
}