/* $Id: gluegen.c,v 1.6 2003/04/06 03:47:38 wafer Exp $ */

#include <stdio.h>
#include <stdlib.h>
#include "glue.h"

const char *type_to_string (type_t t)
{
     switch (t) {
     case double_t:
	  return "double";
     case int_t:
	  return "int";
     case string_t:
	  return "string";
     }
     return NULL;
}

void glue_gen (FILE *glue_file, FILE *glue_header_file, FILE *register_file)
{
     int j;
     static int n_reg_func = 0;

     /* first make a glue wrapper */
     fprintf(glue_file, "value_t %s_glue (value_t *argv, int argc)\n{\n", 
	     i->name); 
     fprintf(glue_file, "\tvalue_t ret;\n");
     if (i->ret != void_t) {
	  /* make a temporary variable to hold the function return */
	  fprintf(glue_file, "\t%s temp;\n", type_to_string(i->ret));
     }
     /* set up the arguments */
     for (j = 0; j < i->argc; ++j) 
	  fprintf(glue_file, "\t%s arg%d;\n", type_to_string(i->argt[j]), j);

     fprintf(glue_file, "\n");
     for (j = 0; j < i->argc; ++j) {
	  fprintf(glue_file, "\tconv_");
	  switch (i->argt[j]) {
	  case double_t:
	       fprintf(glue_file, "float(&");
	       break;
	  case int_t:
	       fprintf(glue_file, "int(&");
	       break;
	  case string_t:
	       fprintf(glue_file, "string(");
	       break;
	  }
	  fprintf(glue_file, "arg%d, &argv[%d]);\n", j, j);
     }

     /* make the function call */
     fprintf(glue_file, "\n");
     if (i->ret != void_t) 
	  fprintf(glue_file, "\ttemp = ");
     else 
	  fprintf(glue_file, "\t");
     fprintf(glue_file, "%s(", i->name);
     for (j = 0; j < i->argc; ++j) {
	  fprintf(glue_file, "arg%d", j);
	  if (j == i->argc - 1)
	       continue;
	  fprintf(glue_file, ",");
     }
     fprintf(glue_file, ");\n");
     /* assign the temporary variable to the right field in the return */
     switch (i->ret) {
     case double_t:
	  fprintf(glue_file, "\n\tret.val_type = %s;\n\tret.value.%s = temp;\n",
		 "val_float", "v_float");
	  break;
     case int_t:
	  fprintf(glue_file, "\n\tret.val_type = %s;\n\tret.value.%s = temp;\n",
		 "val_int", "v_int");
	  break;
     case string_t:
	  fprintf(glue_file, "\n\tret.val_type = %s;\n\t"
		 "strncpy(ret.value.%s, temp, STRING_LIT_LEN);\n",
		 "val_string", "v_string");
	  break;
     case void_t:
	  break;
     }
     /* clean up and leave */
     fprintf(glue_file, "\n\treturn ret;\n}\n\n");

     /* declare it in the header file */
     fprintf(glue_header_file, "value_t %s_glue (value_t *argv, int argc);\n",
	     i->name); 

     /* now register the glue function in the identifier list */
     fprintf(register_file, "\t{\n");
     fprintf(register_file, "\t\tident_t *id = ident_create(\"%s\");\n", 
	     i->name);
     fprintf(register_file, "\t\tid->cont.func = %s_glue;\n", i->name);
     fprintf(register_file, "\t\tid->type = func;\n");
     fprintf(register_file, "\t\tid->is_declared = 1;\n\t}\n");
     
     n_reg_func++;
     return;
}