/* wmem_user_cb.c

 * Wireshark Memory Manager User Callbacks

 * Copyright 2012, Evan Huus <eapache@gmail.com>

 *

 * Wireshark - Network traffic analyzer

 * By Gerald Combs <gerald@wireshark.org>

 * Copyright 1998 Gerald Combs

 *

 * SPDX-License-Identifier: GPL-2.0-or-later

 */

#include "wmem_core.h"

#include "wmem_allocator.h"

#include "wmem_user_cb.h"

#include "wmem_user_cb_int.h"

typedef struct _wmem_user_cb_container_t {

    wmem_user_cb_t                    cb;

    void                             *user_data;

    struct _wmem_user_cb_container_t *next;

    unsigned                          id;

} wmem_user_cb_container_t;

void

wmem_call_callbacks(wmem_allocator_t *allocator, wmem_cb_event_t event)

{

    wmem_user_cb_container_t **prev, *cur;

    bool again;

    prev = &(allocator->callbacks);

    cur  = allocator->callbacks;

    while (cur) {

        /* call it */

        again = cur->cb(allocator, event, cur->user_data);

        /* if the callback requested deregistration, or this is being triggered

         * by the final destruction of the allocator, remove the callback */

        if (! again || event == WMEM_CB_DESTROY_EVENT) {

            *prev = cur->next;

            wmem_free(NULL, cur);

            cur = *prev;

        }

        else {

            prev = &(cur->next);

            cur  = cur->next;

        }

    }

}

unsigned

wmem_register_callback(wmem_allocator_t *allocator,

        wmem_user_cb_t callback, void *user_data)

{

    wmem_user_cb_container_t *container;

    static unsigned next_id = 1;

    container = wmem_new(NULL, wmem_user_cb_container_t);

    container->cb        = callback;

    container->user_data = user_data;

    container->next      = allocator->callbacks;

    container->id        = next_id++;

    allocator->callbacks = container;

    return container->id;

}

void

wmem_unregister_callback(wmem_allocator_t *allocator, unsigned id)

{

    wmem_user_cb_container_t **prev, *cur;

    prev = &(allocator->callbacks);

    cur  = allocator->callbacks;

    while (cur) {

        if (cur->id == id) {

            *prev = cur->next;

            wmem_free(NULL, cur);

            return;

        }

        prev = &(cur->next);

        cur  = cur->next;

    }

}

/*

 * Editor modelines  -  https://www.wireshark.org/tools/modelines.html

 *

 * Local variables:

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 * End:

 *

 * vi: set shiftwidth=4 tabstop=8 expandtab:

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 */