/*
* Copyright (c) 2018 The TCPDUMP project
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that: (1) source code
* distributions retain the above copyright notice and this paragraph
* in its entirety, and (2) distributions including binary code include
* the above copyright notice and this paragraph in its entirety in
* the documentation or other materials provided with the distribution.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND
* WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT
* LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE.
*/

#include <config.h>

#include <stdlib.h>
#include "netdissect-alloc.h"

static void nd_add_alloc_list(netdissect_options *, nd_mem_chunk_t *);

/*
* nd_free_all() is intended to be used after a packet printing
*/

/* Add a memory chunk in allocation linked list */
static void
nd_add_alloc_list(netdissect_options *ndo, nd_mem_chunk_t *chunkp)
{
       if (ndo->ndo_last_mem_p == NULL)        /* first memory allocation */
               chunkp->prev_mem_p = NULL;
       else                                    /* previous memory allocation */
               chunkp->prev_mem_p = ndo->ndo_last_mem_p;
       ndo->ndo_last_mem_p = chunkp;
}

/* malloc replacement, with tracking in a linked list */
void *
nd_malloc(netdissect_options *ndo, size_t size)
{
       nd_mem_chunk_t *chunkp = malloc(sizeof(nd_mem_chunk_t) + size);
       if (chunkp == NULL)
               return NULL;
       nd_add_alloc_list(ndo, chunkp);
       return chunkp + 1;
}

/* Free chunks in allocation linked list from last to first */
void
nd_free_all(netdissect_options *ndo)
{
       nd_mem_chunk_t *current, *previous;
       current = ndo->ndo_last_mem_p;
       while (current != NULL) {
               previous = current->prev_mem_p;
               free(current);
               current = previous;
       }
       ndo->ndo_last_mem_p = NULL;
}