#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include "strlist.h"

static str_node *strlist_head = NULL ;
static str_node *strlist_last = NULL ;


/*************************************************************
Print message and abort.
*/
static void crash_and_burn(char * mesg) {

   fprintf (stderr, "Error: %s\n", mesg) ;
   abort() ;
}


/*************************************************************
Initialize a linked list of strings with dummy header.
*/
void strlist_init() {
   str_node *tptr ;

   if (! (tptr = malloc(sizeof(str_node)))) 
	  crash_and_burn("malloc() out of memory!!") ;
   tptr->number = -1 ;
   tptr->str = NULL ;
   tptr->next = NULL ;
   
   strlist_head = tptr ;
   strlist_last = tptr ;
}


/*************************************************************
Add str_node at the end.
*/
void strlist_append(int number, char *str) {
   str_node *tptr ;

   if (! (tptr = malloc(sizeof(str_node)))) 
	  crash_and_burn("malloc() out of memory!!") ;
   tptr->number = number ;
   tptr->str = strdup(str) ;
   tptr->next = NULL ;
   
   assert(strlist_last != NULL) ;

   strlist_last->next = tptr ;
   strlist_last = tptr ;
}

/*************************************************************
Deallocate list
*/
void strlist_destroy(char *str) {
   str_node *ptr1, *fptr;

   ptr1 = strlist_head ;
   strlist_head = NULL ;
   strlist_last = NULL ;
 
   while(ptr1 != NULL) {
       fptr = ptr1 ;
	   ptr1 = ptr1->next ;
	   
	   free(fptr->str) ;   /* OK to free NULL pointer */
	   free(fptr) ;
   }

}


/*************************************************************
Print out string constants
*/
void strlist_output(FILE *of) {
   str_node *ptr ;

   fprintf(of, "\n; String constants\n") ;
   
   assert(strlist_head != NULL) ;
   ptr = strlist_head->next ;

   while(ptr != NULL) {
      fprintf(of, "%s%d:\t", STR_LABEL_PREFIX, ptr->number) ;
	  fprintf(of, "db\t\"%s\", 0\n", ptr->str) ;
	  ptr = ptr->next ;
   }

   fprintf(of, "\n") ;
}