#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include "assemble.h"

void do_branch (long address, OperandType *operand, Label_Node *label_head, int pass, int line_no)
{
   int label, i, hash;
   long reladdress;
   
   /* It's a branch instruction */
   operand->addtype = REL;
   strcpy (operand->formatted, operand->orig);
   
   /* Work out it's value. either a number or a label */
   if (operand->orig[0] == '#')
     {
	hash = 1;
	reladdress = get_value (operand, &operand->orig[1], label_head, pass, line_no);
     }
   else
     {
	hash = 0;
	reladdress = get_value (operand, operand->orig, label_head, pass, line_no);
     }
	
   label = 0;
   if (operand->orig[hash] != '$')
     if (operand->orig[hash] != '%')
       for (i=hash; i<strlen(operand->orig); i++)
	 if (!isdigit(operand->orig[i]))
	   label = 1;
   
   /* If it isn't a label use the value directly */
   if (label == 0)
     operand->value = (char) reladdress;
   else
     /* If the label is recognised, use an offset value */
     if (reladdress != 0x666666)
       operand->value = (reladdress - address - 2);
   else
     operand->value = 0x66;
   
   /* Is it a valid branch? */
   if (operand->value > 127 || operand->value < -127)
     {
	fprintf (stderr, "Jump too large (%ld) at line /foo/. Make +/-127\n", operand->value);
	exit (EXIT_FAILURE);
     }
   else
     {
	operand->value = operand->value & 0xff;
	sprintf (operand->formatted, "$%2lX", operand->value);
     }
}