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#include "main.h"
#include "serial.h"
#include "modem.h"
struct prog_params parse_args(int argc, char* argv[])
{
struct prog_params ret;
memset(&ret, 0, sizeof(ret));
for (int i = 1; i < argc; i++)
{
int i_cpy = i; //i might be changed in loop
if(argv[i_cpy][0] == '-')
{
for (int o = 1; o < strlen(argv[i_cpy]); o++)
{
switch (argv[i_cpy][o])
{
case 'h':
ERROR_HELP("");
break;
case 'p':
ret.telnet = 1;
ret.port = atoi(argv[i_cpy + 1]);
i++;
break;
case 'i':
ret.telnet = 1;
ret.ip = argv[i_cpy + 1];
i++;
break;
case 's'://Serial modem
ret.serial = 1;
ret.serial_port = argv[i_cpy + 1];
i++;
break;
case 'b':
ret.serial = 1;
ret.serial_baudrate = atoi(argv[i_cpy + 1]);
i++;
break;
case 'f'://PID file for spawned children
ret.fork = 1;
ret.pidfile = argv[i_cpy + 1];
i++;
break;
default:
ERROR_HELP("Unrecognized Option: '%c'\n", argv[i_cpy][o]);
break;
};//switch
}//for
}//if
else
{
//Copy the rest as arguments for prog to exec
ret.run_argc = argc - i_cpy;
ret.run_argv = &(argv[i_cpy]);
break;
}//else
}//for
if(ret.telnet == ret.serial)//run EITHER in telnet OR modem mode
ERROR_HELP("Select either modem OR telnet.\n");
return ret;
}
void handle_connection(int _socket, struct sockaddr_in _addr, int argc, char* argv[])
{
pid_t pid = fork();
if( pid > 0 )
{
close(_socket);
return;
}
else if ( pid < 0 )
return;
//This is here for later
//This should handle a premature closed socket from client to not create unused processes
pid = fork();
if(pid > 0)
{
close(_socket);
//Instead of waiting for pid, check if process is running AND socket is still open
wait(0);
exit(0);
}
else if(pid < 0)
exit(1);
//Redirect STDIO to socket
dup2(_socket, STDIN_FILENO);
dup2(_socket, STDOUT_FILENO);
dup2(_socket, STDERR_FILENO);
char* arv[argc + 1];
for(int i = 0; i < argc; i++)
arv[i] = argv[i];
arv[argc] = NULL;
execv(argv[0], arv);
PRINT_ERROR("EXEC failed");
close(_socket);
exit(1);
}
int main(int argc, char* argv[])
{
signal(SIGCHLD,SIG_IGN); //Ignore sigchld
struct prog_params params = parse_args(argc, argv);
//Fork and write PID to pidfile
if(params.fork)
{
FILE* pidfile = fopen(params.pidfile, "w");
if(!pidfile)
{
PRINT_ERROR("Unable to open pidfile for writing");
exit(1);
}
pid_t pid = fork();
if(pid < 0)
{
PRINT_ERROR("fork() failed");
exit(1);
}
else if(pid > 0)
{
fprintf(pidfile, "%i", pid);
printf("Forked with PID %i\n", pid);
fclose (pidfile);
exit(0);
}
fclose (pidfile);
}//if params.fork
DEBUG_PRINTF("%s, %i\n", params.run_argv[0], params.run_argc);
if ( params.serial )
dialup_server(params);
else if (params.telnet)
telnet_server(params);
return 0;
}
void dialup_server(struct prog_params params)
{
printf("Starting dialup server\n");
int fd = open (params.serial_port, O_RDWR | O_NOCTTY | O_SYNC);
if (fd < 0)
{
PRINT_ERROR("Failed to open serial port");
return;
}
set_interface_attribs (fd, params.serial_baudrate, 0);
set_blocking (fd, 0);
int ret = modem_accept_wait(fd);
if(ret)
return;
DEBUG_PRINTF("Connection established\n");
modem_run(fd, params.run_argc, params.run_argv);
}
void telnet_server(struct prog_params params)
{
signal(SIGCHLD,SIG_IGN); //Ignore sigchld
int server_socket, client_socket;
struct sockaddr_in socket_address, client_address;
size_t claddrsize = sizeof(client_address);
if ( (server_socket = socket(AF_INET, SOCK_STREAM, 0)) == -1 )
{
printf("Error creating socket: %i: %s\n", errno, strerror(errno));
exit(1);
}
memset (&socket_address, 0, sizeof(socket_address));
socket_address.sin_family = AF_INET;
socket_address.sin_port = htons( params.port );
if ( (bind(server_socket, &socket_address, sizeof(socket_address))) == -1 )
{
printf("Error binding socket: %i: %s\n", errno, strerror(errno));
exit(1);
}
if ( (listen(server_socket, 10)) == -1 )
{
printf("Error listening socket: %i: %s\n", errno, strerror(errno));
exit(1);
}
while(1)
{
client_socket = accept(server_socket, &client_address, &claddrsize);
DEBUG_PRINTF("Connection: %s\n", inet_ntoa(client_address.sin_addr));
handle_connection(client_socket, client_address, params.run_argc, params.run_argv);
}
}
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