how to establish sip session in .c programming between client and server - c++

Question

this is client server application I want to establish SIP (session initiation protocol) between client and server.
So please anyone guide me how can I do this.
server.c:
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <sys/wait.h>
#include <signal.h>
#include <netinet/tcp.h>
#define MYPORT 3490 // the port users will be connecting to
#define BACKLOG 10 // how many pending connections queue will hold
#define MAXDATASIZE 100
void str_server(int);
void sigchld_handler(int s)
{
while(waitpid(-1, NULL, WNOHANG) > 0);
}
int main(void)
{
int sockfd, numbytes,new_fd, optlen; // listen on sock_fd, new connection on new_fd
struct sockaddr_in my_addr; // my address information
struct sockaddr_in their_addr; // connector's address information
struct tcp_info info;
socklen_t sin_size;
struct sigaction sa;
char buf[MAXDATASIZE];
int yes=1;
if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) == -1) {
perror("socket");
exit(1);
}
if (setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(int)) == -1) {
perror("setsockopt");
exit(1);
}
my_addr.sin_family = AF_INET; // host byte order
my_addr.sin_port = htons(MYPORT); // short, network byte order
my_addr.sin_addr.s_addr = INADDR_ANY; // automatically fill with my IP
memset(my_addr.sin_zero, '\0', sizeof my_addr.sin_zero);
if (bind(sockfd, (struct sockaddr *)&my_addr, sizeof my_addr) == -1) {
perror("bind");
exit(1);
}
if (listen(sockfd, BACKLOG) == -1) {
perror("listen");
exit(1);
}
sa.sa_handler = sigchld_handler; // reap all dead processes
sigemptyset(&sa.sa_mask);
sa.sa_flags = SA_RESTART;
if (sigaction(SIGCHLD, &sa, NULL) == -1) {
perror("sigaction");
exit(1);
}
while(1) { // main accept() loop
sin_size = sizeof their_addr;
getchar();
if ((new_fd = accept(sockfd, (struct sockaddr *)&their_addr, \
&sin_size)) == -1) {
perror("accept");
continue;
}
printf("server: got connection from %s\n", \
inet_ntoa(their_addr.sin_addr));
if (!fork()) { // this is the child process
close(sockfd); // child doesn't need the listener
if ((numbytes=recv(new_fd, buf, MAXDATASIZE-1, 0)) == -1) {
perror("recv");
exit(1);
}
buf[numbytes] = '\0';
printf("Received From Client: %s\n",buf);
str_server(sockfd);
FILE *fp = fopen( "adventure.mpg", "rb" );
//if(!fork())
// execlp("gedit", "gedit", "SIPFILE.txt", NULL);
//system("popen /home/umair/Documents/CurrentData/SIPFILE.txt");
//ShellExecute(GetDesktopWindow(), "open","ls /home/umair/Documents
/CurrentData/SIPFILE.txt",NULL, NULL, SW_SHOW);
if (send(new_fd, "Hello, world!\n", 14, 0) == -1)
perror("send");
close(new_fd);
exit(0);
}
close(new_fd); // parent doesn't need this
}
return 0;
}
void str_server(int sock)
{
char buf[1025];
const char* filename = "test.text";
FILE *file = fopen(filename, "rb");
if (!file)
{
printf("Can't open file for reading");
return;
}
while (!feof(file))
{
int rval = fread(buf, 1, sizeof(buf), file);
if (rval < 1)
{
printf("Can't read from file");
fclose(file);
return;
}
int off = 0;
do
{
int sent = send(sock, &buf[off], rval - off, 0);
if (sent < 1)
{
// if the socket is non-blocking, then check
// the socket error for WSAEWOULDBLOCK/EAGAIN
// (depending on platform) and if true then
// use select() to wait for a small period of
// time to see if the socket becomes writable
// again before failing the transfer...
printf("Can't write to socket");
fclose(file);
return;
}
off += sent;
}
while (off < rval);
}
fclose(file);
}
//client.c :
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <netdb.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <sys/socket.h>
#include <netinet/tcp.h>
#define PORT 3490 // the port client will be connecting to
#define MAXDATASIZE 100 // max number of bytes we can get at once
void RecvFile(int , const char* );
FILE *filename;
int main(int argc, char *argv[])
{
int sockfd, numbytes, optlen;
char buf[MAXDATASIZE];
char *message;
struct hostent *he;
struct tcp_info info;
struct sockaddr_in their_addr; // connector's address information
if (argc != 2) {
fprintf(stderr,"usage: client hostname\n");
exit(1);
}
if ((he=gethostbyname(argv[1])) == NULL) { // get the host info
herror("gethostbyname");
exit(1);
}
if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) == -1) {
perror("socket");
exit(1);
}
their_addr.sin_family = AF_INET; // host byte order
their_addr.sin_port = htons(PORT); // short, network byte order
their_addr.sin_addr = *((struct in_addr *)he->h_addr);
memset(their_addr.sin_zero, '\0', sizeof their_addr.sin_zero);
if (connect(sockfd, (struct sockaddr *)&their_addr,
sizeof their_addr) == -1) {
perror("connect");
exit(1);
}
printf("connect successfull\n");
/* if (send(sockfd, "Hello, world!\n", 14, 0) == -1)
perror("send");
printf("send successfull\n");
*/
message = "GET /?st=1 HTTP/1.1\r\nHost: www.msn.com\r\n\r\n";
if( send(sockfd , message , strlen(message) , 0) < 0)
{
puts("Send failed");
return 1;
}
puts("Data Send\n");
RecvFile(sockfd , message);
optlen = sizeof(info);
if ((numbytes=recv(sockfd, buf, MAXDATASIZE-1, 0)) == -1) {
perror("recv");
exit(1);
}
buf[numbytes] = '\0';
printf("Received: %s\n",buf);
close(sockfd);
return 0;
}
void RecvFile(int sock, const char* filename)
{
int rval;
char buf[0x1000];
FILE *file = fopen(filename, "wb");
if (!file)
{
printf("Can't open file for writing");
return;
}
do
{
rval = recv(sock, buf, sizeof(buf), 0);
if (rval < 0)
{
// if the socket is non-blocking, then check
// the socket error for WSAEWOULDBLOCK/EAGAIN
// (depending on platform) and if true then
// use select() to wait for a small period of
// time to see if the socket becomes readable
// again before failing the transfer...
printf("Can't read from socket");
fclose(file);
return;
}
if (rval == 0)
break;
int off = 0;
do
{
int written = fwrite(&buf[off], 1, rval - off, file);
if (written < 1)
{
printf("Can't write to file");
fclose(file);
return;
}
off += written;
}
while (off < rval);
}
while (!feof(file));
fclose(file);
}
Any Suggestion?

Answer 1

I am not sure what you are trying to do with SIP, but the code snippet you've provided shows only establishing a TCP/IP connection. If you intend to do a SIP server-client application, I suggest that you look for a library to help you along the way.
One that I know of that is very complete is called Sofia SIP:
http://sofia-sip.sourceforge.net/
It's written by Nokia for Linux in C language.
Source code is available here: http://gitorious.org/sofia-sip/sofia-sip/trees/master
(Older http://sourceforge.net/p/sofia-sip/git/ci/master/tree/)

Answer 2

you can learn about sipp scenarios and message passing through this utility and its documentation.