connect_modem.c

仿真测试接口程序。根据电总《用户接入网管理功能与管理接口技术规范》之《与112集中受理系统接口规范》

#include    <stdio.h>
#include    <poll.h>

#include    <errno.h>

extern int errno;
extern int logfp;

extern void writelog(int logfp, char *str);
char *wait_cmd_ret(int fd, int timeval);
extern void write_msg(char *head, unsigned char *msg, int msg_len);

/*********************************************************
Function:int connect_modem(int fd, const char *phone_no)
Narrative:
	Check local modem and connect to remote modem.

Param:	int fd	- socket id
 	const char *phone_no - a pointer to telephone number of  remote modem

Return: 0	OK.
	-1 	Local modem fail.
	-2	Connect to remote modem fail.
*********************************************************/
int connect_modem(int fd, const char *phone_no)
{
	char modem_cmd_str[128];
	char *cmd_ret_str;
	int ret_val;
	char *test_str = "UUU";

	/* read previous infomation from port */
	do
	{
		cmd_ret_str = wait_cmd_ret(fd, 100);
	}
	while (cmd_ret_str[0] != 0);

	/* check local modem connection */
	write(fd, "\r\n+++", 5);
	cmd_ret_str = wait_cmd_ret(fd, 2000);

	write(fd, "at\r\n", 4);
	cmd_ret_str = wait_cmd_ret(fd, 2000);
	if (strstr(cmd_ret_str, "at") == NULL)
	{
		if (strstr(cmd_ret_str, "OK"))
		{
			write(fd, "ato\r\n", 5);
			cmd_ret_str = wait_cmd_ret(fd, 10000);
			return 0;
		}
		else
			return -1;
	}

	/*hang up the modem */
	write(fd, "ath\r\n", 5);
	cmd_ret_str = wait_cmd_ret(fd, 2000);
	if (cmd_ret_str[0] == 0)
		return -1;

	/*set modem to check BUSY */
	write(fd, "atx4\r\n", 6);
	cmd_ret_str = wait_cmd_ret(fd, 2000);

	/*reconnect to switcher port */
	sprintf(modem_cmd_str, "atdt%s\r\n", phone_no);
	write(fd, modem_cmd_str, strlen(modem_cmd_str));
	cmd_ret_str = wait_cmd_ret(fd, 35000);

	if (cmd_ret_str[0] == 0)
		return -2;

	if (strstr(cmd_ret_str, "CONNECT"))
	{
		writelog(logfp, cmd_ret_str);
/*    cmd_ret_str=wait_cmd_ret(fd,10000); */
		return 0;
	}
	else
	{
		write(fd, "ath\r\n", 5);
		cmd_ret_str = wait_cmd_ret(fd, 2000);
		return -2;
	}
}

/*********************************************************
Function:char *wait_cmd_ret(int fd, int timeval)
Narrative:
	Recieve return stirng from modem.

Param:	int fd	- socket id
 	int timeval	- poll system call waiting time

Return: cmd_ret_str recieved string.
*********************************************************/
char *wait_cmd_ret(int fd, int timeval)
{
	static char cmd_ret_str[512];
	struct pollfd com_pollfd;
	int ret_len, rc;
	int poll_rval;
	char ch;
	/*intial the struct com_pollfd */
	com_pollfd.fd = fd;
	com_pollfd.events = POLLIN;
	com_pollfd.revents = 0;

	cmd_ret_str[0] = 0;
	ret_len = 0;
	for (;;)
	{
		poll_rval = poll(&com_pollfd, 1, timeval);

		/* System call poll() error */
		if (poll_rval < 0 && errno != EINTR)
		{
			writelog(logfp, "serial port poll() failed");
			return (cmd_ret_str);
		}

		/* Timeout */
		if (poll_rval == 0)
		{
			if (timeval == 10000)
			{
				write_msg("Modem!\n", (unsigned char *) cmd_ret_str, ret_len);
/*rc=write(fd,"+++ATH\r\n+++ATH\r\n+++ATH\r\n",24); */
			}
			return (cmd_ret_str);
		}

		/* normal data arriving at this fd */
		if (com_pollfd.revents & POLLIN)
		{
			rc = read(fd, cmd_ret_str + ret_len, 1);
			if (rc == 1)
			{
				ch = cmd_ret_str[ret_len];
				ret_len += rc;
				cmd_ret_str[ret_len] = 0;

				if (ret_len > 500)
					return (cmd_ret_str);
				if (ch == '\n')
				{
					if (strstr(cmd_ret_str, "+++"))
						return (cmd_ret_str);
					if (strstr(cmd_ret_str, "OK"))
						return (cmd_ret_str);
					if (strstr(cmd_ret_str, "CONNECT"))
					{
						return (cmd_ret_str);
					}
					if (strstr(cmd_ret_str, "NO CARRIER"))
						return (cmd_ret_str);
					if (strstr(cmd_ret_str, "BUSY"))
						return (cmd_ret_str);
					if (strstr(cmd_ret_str, "NO ANSWER"))
						return (cmd_ret_str);
					if (strstr(cmd_ret_str, "NO DIAL TONE"))
						return (cmd_ret_str);
				}
			}
		}
	}
}