/* symtab.c     Routines to maintain and manipulate a symbol table
 *
 *   These routines donated to the NASM effort by Graeme Defty.
 *
 * The Netwide Assembler is copyright (C) 1996 Simon Tatham and
 * Julian Hall. All rights reserved. The software is
 * redistributable under the licence given in the file "Licence"
 * distributed in the NASM archive.
 */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <malloc.h>

#include "symtab.h"
#include "hash.h"

#define SYMTABSIZE 64
#define slotnum(x) (hash((x)) % SYMTABSIZE)

/* ------------------------------------- */
/* Private data types */

typedef struct tagSymtabNode {
  struct tagSymtabNode  * next;
  symtabEnt             ent;
} symtabNode;

typedef symtabNode *(symtabTab[SYMTABSIZE]); 

typedef symtabTab *symtab;                   

/* ------------------------------------- */
void *
symtabNew(void)
{
  symtab mytab;

  mytab = (symtabTab *) calloc(SYMTABSIZE ,sizeof(symtabNode *));
  if (mytab == NULL) {
    fprintf(stderr,"symtab: out of memory\n");
    exit(3);
  }

  return mytab;
}

/* ------------------------------------- */
void
symtabDone(void *stab)
{
   symtab mytab = (symtab)stab;
   int i;
   symtabNode *this, *next;

   for (i=0; i < SYMTABSIZE; ++i) {

      for (this = (*mytab)[i]; this; this=next)
      { next = this->next;   free (this); }

   }
   free (*mytab);
}

/* ------------------------------------- */
void
symtabInsert(void *stab, symtabEnt *ent)
{
  symtab mytab = (symtab) stab;
  symtabNode *node;
  int slot;

  node = malloc(sizeof(symtabNode));
  if (node == NULL) {
    fprintf(stderr,"symtab: out of memory\n");
    exit(3);
  }

  slot = slotnum(ent->name);

  node->ent = *ent;
  node->next = (*mytab)[slot];
  (*mytab)[slot] = node; 
}

/* ------------------------------------- */
symtabEnt *
symtabFind(void *stab, const char *name)
{
   symtab mytab = (symtab) stab;
   int slot = slotnum(name);
   symtabNode *node = (*mytab)[slot];

   while (node) {
      if (!strcmp(node->ent.name,name)) {
	 return &(node->ent);
      }
      node = node->next;
   }  

   return NULL;
}

/* ------------------------------------- */
void
symtabDump(void *stab, FILE* of)
{
   symtab mytab = (symtab)stab;
   int i;
   char *SegNames[3]={"code","data","bss"};

   fprintf(of, "Symbol table is ...\n");
   for (i=0; i < SYMTABSIZE; ++i) {
      symtabNode        *l = (symtabNode *)(*mytab)[i];

      if (l) {
	 fprintf(of, " ... slot %d ...\n", i);
      }
      while(l) {
	if ((l->ent.segment) == -1) {
	    fprintf(of,"%-32s Unresolved reference\n",l->ent.name);
	} else {		
	    fprintf(of, "%-32s %s:%08lx (%ld)\n",l->ent.name,
	    SegNames[l->ent.segment],
	    l->ent.offset, l->ent.flags);
	}
	l = l->next;
      }
   }
   fprintf(of, "........... end of Symbol table.\n");
}