tap.c

使用TAP的蜂窝型GSM手机短消息服务中心

/* -------------------------------------------------------------------- */
/* -------------------------------------------------------------------- */
static void TAP_checksum(char *message)
{
	int 	i,
		checksum;

		
	checksum  = 0;
	for (i=0; i<sms_strlen(message); i++)
	{	checksum += message[i];
	}

	checksum = (checksum & 0x0FFF);	/* Mask low 12Bits */

	message[i]   = (((checksum & 0x0F00) >> 8) | 0x30);
	message[i+1] = (((checksum & 0x00F0) >> 4) | 0x30);
	message[i+2] = (((checksum & 0x000F)     ) | 0x30);
	message[i+3] = '\0';
}


/* -------------------------------------------------------------------- */
/* -------------------------------------------------------------------- */
static void TAP_hangup(void)
{	default_hangup((DRIVER_DEFAULT_ENV *)(&driver_env));
}

/* -------------------------------------------------------------------- */
/* -------------------------------------------------------------------- */
static int TAP_send_disconnect(void)
{
	lprintf(LOG_STANDARD, "Disconnect...\n");
	
	if (TAP_DISCONNECT)
	{	
		twrite(FD, REQ7, sms_strlen(REQ7), WRITETIMEOUT);
		if (expstr(FD, buf, ACK8, MAX_RESPONSE_BUFSIZE, TIMEOUT) == 0)
		{
			lprintf(LOG_STANDARD, "Disconnected from SMSC\n");
		}
		else
		{	lprintf(LOG_STANDARD, "Failed to disconnect from SMSC\n");
		
			TAP_hangup();
			return ETAP_NODISCONNECT;
		}
	}

	return 0;
}


/* -------------------------------------------------------------------- */
/* -------------------------------------------------------------------- */
static int TAP_login(void)
{
	int 	i;


	lprintf(LOG_STANDARD, "Login...\n");
	

	/* Resend the S_CR every 2 seconds	*/
	/* until ID= received, only try		*/
	/* 5 times then give up.		*/

	sms_usleep(INITLOGINSLEEP);
	for (i=0; i < MAX_TRIES; i++)
	{
		twrite(FD, REQ1, sms_strlen(REQ1), WRITETIMEOUT);

		if (expstr(FD, buf, ACK1, MAX_RESPONSE_BUFSIZE, LOGINTIMEOUT) == 0)
		{	
			lprintf(LOG_STANDARD, "SMSC Acknowledgment received\n");	
			break;
		}

		lprintf(LOG_STANDARD, "SMSC Retry for Acknowledgment\n");	
		sms_usleep(LOGINSLEEP);
	}

	if (i == MAX_TRIES)
	{
		lprintf(LOG_STANDARD, "Failed Acknowledgment %ld retries attempted\n", MAX_TRIES);
		
		TAP_hangup();
		return ETAP_NOACK;
	}

	
	/* Send S_ESC <TAP_SELECT> S_CR and get back	*/
	/* the acknowledgement S_ACK S_CR	*/

	twrite(FD, REQ2a,      sms_strlen(REQ2a),      WRITETIMEOUT);
	twrite(FD, TAP_SELECT, sms_strlen(TAP_SELECT), WRITETIMEOUT);
	twrite(FD, REQ2b,      sms_strlen(REQ2b),      WRITETIMEOUT);

	if (expstr(FD, buf, ACK2, MAX_RESPONSE_BUFSIZE, TIMEOUT) == 0)
	{
		lprintf(LOG_STANDARD, "Login successful\n");
	}
	else
	{	lprintf(LOG_STANDARD, "Login failed\n");
	
		TAP_hangup();
		return ETAP_NOLOGIN;
	}

	if (expstr(FD, buf, ACK3, MAX_RESPONSE_BUFSIZE, TIMEOUT) == 0)
	{
		lprintf(LOG_STANDARD, "Ready to receive message\n");
	}
	else
	{	lprintf(LOG_STANDARD, "SMSC NOT Ready to receive message\n");
		
		TAP_hangup();
		return ETAP_NOREADY;
	}

	return 0;
}


/* -------------------------------------------------------------------- */
/* -------------------------------------------------------------------- */
static void TAP_buildmessage(char *tap_message, char *msisdn, char *message)
{
	int 	i;
	char	*ptr;


	/* ---------------------------- */

	tap_message[0] = '\0';
	
	sms_strcat(tap_message, REQ3);
	sms_strcat(tap_message, msisdn);
	sms_strcat(tap_message, REQ4);

	
	/* Convert message so that it contains	*/
	/* only TAP valid characters		*/
	/* any invalid characters will be	*/
	/* mapped to a SPACE			*/
	/* Add to tap_message			*/

	ptr = tap_message;
	while(*ptr != '\0')
	{	ptr++;
	}

	for (i=0; i<sms_strlen(message) +1; i++)
	{	*ptr = TAP_charset[(int)message[i]];
		ptr++;
	}

	*ptr = '\0';

	sms_strcat(tap_message, REQ5);


	/* Generate TAP checksum. Consisting	*/
	/* of 3 characters. Append this to end	*/
	/* of tap_message.			*/

	TAP_checksum(tap_message);

	sms_strcat(tap_message, REQ6);
}


/* -------------------------------------------------------------------- */
/* -------------------------------------------------------------------- */
static int TAP_sendmessage(char *msisdn, char *message)
{
	char 	tap_message[MAX_MESSAGE + MAX_ENVELOPE];


	TAP_buildmessage(tap_message, msisdn, message);
	
	twrite(FD, tap_message, sms_strlen(tap_message), WRITETIMEOUT);
	if (TAP_RESPONSE)
	{	
		if (expstr(FD, buf, ACK4, MAX_RESPONSE_BUFSIZE, DELIVERTIMEOUT) == 0)
		{
			lprintf(LOG_STANDARD, "Received Message Response: %s\n", buf);
		}
		else
		{	lprintf(LOG_STANDARD, "No Message Response\n");
			
			TAP_hangup();
			return ETAP_NOMESSAGE;
		}
	}

	if (expstr(FD, buf, ACK5, MAX_RESPONSE_BUFSIZE, TIMEOUT) == 0)
	{
		lprintf(LOG_STANDARD, "Successful message submission\n");
	}
	else
	{ 	if (strncmp(&buf[sms_strlen(buf) - sms_strlen(ACK6)], ACK6, sms_strlen(ACK6)) == 0)
		{
			lprintf(LOG_STANDARD, "Message submission failed - Transmission incomprehensible\n");
		}
		else if (strncmp(&buf[sms_strlen(buf) - sms_strlen(ACK7)], ACK7, sms_strlen(ACK7)) == 0)
		{
			lprintf(LOG_STANDARD, "Message submission failed - Problem with message\n");
		}
		else
		{	lprintf(LOG_STANDARD, "Message submission failed - Reason Unknown\n");
		}
		
		TAP_hangup();
		return ETAP_NODELIVERY;
	}

	return 0;
}

/* -------------------------------------------------------------------- */
/* -------------------------------------------------------------------- */
DEVICE_ENTRY tap_device = {
	"TAP",
	resource_list,
	(DRIVER_DEFAULT_ENV *)(&driver_env),

	default_init,
	default_main,
	default_validate_numeric_id,
	default_dial,
	default_hangup,
	TAP_send_disconnect,
	default_multiple_counted_deliver,
	TAP_sendmessage,
	TAP_login
};