/* $NetBSD: overlay.c,v 1.1 2020/06/26 03:23:04 thorpej Exp $ */

/*-
* Copyright (c) 2020 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Jared McNeill <[email protected]> and Jason R. Thorpe.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
*    notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
*    notice, this list of conditions and the following disclaimer in the
*    documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/

#include "efiboot.h"
#include "overlay.h"

#include <sys/queue.h>

int     dtoverlay_enabled = 1;

struct dtoverlay_entry {
       TAILQ_ENTRY(dtoverlay_entry) entries;
       char overlay_path[];
};
TAILQ_HEAD(, dtoverlay_entry) dtoverlay_entries =
   TAILQ_HEAD_INITIALIZER(dtoverlay_entries);

#define DTOVERLAY_ENTRY_SIZE(p) (sizeof(struct dtoverlay_entry) + strlen(p) + 1)

void
dtoverlay_foreach(void (*fn)(const char *))
{
       struct dtoverlay_entry *d;

       TAILQ_FOREACH(d, &dtoverlay_entries, entries) {
               fn(d->overlay_path);
       }
}

void
dtoverlay_add(const char *overlay_path)
{
       struct dtoverlay_entry *d;

       /* Trim leading whitespace */
       while (*overlay_path == ' ' || *overlay_path == '\t')
               ++overlay_path;

       /* Duplicate check */
       TAILQ_FOREACH(d, &dtoverlay_entries, entries) {
               if (strcmp(d->overlay_path, overlay_path) == 0)
                       return;
       }

       /* Add to list of overlays. */
       d = alloc(DTOVERLAY_ENTRY_SIZE(overlay_path));
       strcpy(d->overlay_path, overlay_path);
       TAILQ_INSERT_TAIL(&dtoverlay_entries, d, entries);
}

#if 0
void
dtoverlay_remove(const char *overlay_path)
{
       struct dtoverlay_entry *d;

       /* Trim leading whitespace */
       while (*overlay_path == ' ' || *overlay_path == '\t')
               ++overlay_path;

       TAILQ_FOREACH(d, &dtoverlay_entries, entries) {
               if (strcmp(d->overlay_path, overlay_path) == 0) {
                       TAILQ_REMOVE(&dtoverlay_entries, d, entries);
                       dealloc(d, DTOVERLAY_ENTRY_SIZE(d->overlay_path));
                       return;
               }
       }
}
#endif

void
dtoverlay_remove_all(void)
{
       struct dtoverlay_entry *d;

       while ((d = TAILQ_FIRST(&dtoverlay_entries)) != NULL) {
               TAILQ_REMOVE(&dtoverlay_entries, d, entries);
               dealloc(d, DTOVERLAY_ENTRY_SIZE(d->overlay_path));
       }
}

void
dtoverlay_enable(int onoff)
{
       dtoverlay_enabled = onoff;
}