Error msg regarding the Switch loop, What's wrong in my code?

Hi there,

This is my code

Code:

int SRV_TYPE=0;
const int HTTP=80;
const int FTP=21;
const int TELNET=23;
const int POP3=110;
const int SMTP=25;
..
.
.
.
SRV_TYPE= (int)DST_PORT;
switch (SRV_TYPE)
  {	case HTTP:	printf("HTTP Data ..... \n");
  			print_data(tcp_ptr,length);
  			break;
  			
	case FTP:	printf("FTP Data .....\n");
			print_data(tcp_ptr,length);
			break;
			
	case TELNET:	printf("TELNET Data ....\n");
			print_data(tcp_ptr,length);
			break;
	
	case POP3:	printf("POP3 Data ....\n");
			print_data(tcp_ptr,length);
			break;
	
	case SMTP:	printf("SMTP Data ....\n");
			print_data(tcp_ptr,length);
			break;
	
	default :	printf("Unknown Data Type\n");
			break;
  }

When i compile it on FreeBSD, I get this error msg :

Code:

In function `print_tcp_seg':
463: case label does not reduce to an integer constant
467: case label does not reduce to an integer constant
471: case label does not reduce to an integer constant
475: case label does not reduce to an integer constant
479: case label does not reduce to an integer constant
463: warning: unreachable code at beginning of switch statement
*** Error code 1

It seems the problem with the SWITCH statement, I am gessing that there is a mismatch between SRV_TYPE (int) and DST_PORT (u_short), am I right ?
SRV_TYPE=(int) DST_PORT; CAN I DO THAT ????

Any suggestion ?

any tiny help is very highly appreciated.

AHT

Try enumerations instead of "const int":

Code:

enum { HTTP = 80, FTP = 21, TELNET = 23, POP3 = 110, SMTP = 25 };

The typecast is fine, and if you'll pay attention to the actual warnings, it has nothing to do with that line.

Quzah.

What about this line :
SRV_TYPE= (int)DST_PORT;

is it legal in C ?! and does c treat SRV_TYPE as an intger with the value of DST_PORT (0x50)? , which is 80 .

Follow up:
Is there any way in c to check for a variable's value if it is in the enum { HTTP = 80, FTP = 21, TELNET = 23, POP3 = 110, SMTP = 25 }; ?

something like this :
if (service in enum) do something....

is it legal in C ?!

Of course it's legal. It's a typecast. If in doubt, turn on your compiler warnings, and try "-pedantic", and optionally "-ansi" when you compile.

You could always try it and see, you know:

Code:

printf("SRV_TYPE = (int)DST_PORT gives us %d\n", (SRV_TYPE = (int)DST_PORT) );

Is there any way in c to check for a variable's value if it is in the enum { HTTP = 80, FTP = 21, TELNET = 23, POP3 = 110, SMTP = 25 }; ?

Of course you can.

Code:

int x = 21;

if( x == FTP )
    printf("x is set to FTP\n" );
else
    printf("x is set to %d\n", x );

You shouldn't feel afraid to try something. It'll either work or it won't. Either way, perhaps you'll learn something from it.

Quzah.

Originally Posted by althagafi

Follow up:
Is there any way in c to check for a variable's value if it is in the enum { HTTP = 80, FTP = 21, TELNET = 23, POP3 = 110, SMTP = 25 }; ?

something like this :
if (service in enum) do something....

No, but you can write your own function.

Code:

int is_in (int *array, size_t nb, int value)
{
   /* ... */
}

Originally Posted by Emmanuel Delaha

No, but you can write your own function.

Code:

int is_in (int *array, size_t nb, int value)
{
   /* ... */
}

I read that backwards... I figured they wanted to compare to an enum.

Quzah.

Thanx to all.
I got it running fast.

Please, close this thread with high appreciation to all kinds of help.