blob: 6825e985b8c86bc12e6ca9894bb586dc29953b2f [file] [log] [blame]
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
#include <assert.h>
#include <string.h>
#include <nffs/nffs.h>
static void
nffs_area_set_magic(struct nffs_disk_area *disk_area)
{
disk_area->nda_magic[0] = NFFS_AREA_MAGIC0;
disk_area->nda_magic[1] = NFFS_AREA_MAGIC1;
disk_area->nda_magic[2] = NFFS_AREA_MAGIC2;
disk_area->nda_magic[3] = NFFS_AREA_MAGIC3;
}
int
nffs_area_magic_is_set(const struct nffs_disk_area *disk_area)
{
return disk_area->nda_magic[0] == NFFS_AREA_MAGIC0 &&
disk_area->nda_magic[1] == NFFS_AREA_MAGIC1 &&
disk_area->nda_magic[2] == NFFS_AREA_MAGIC2 &&
disk_area->nda_magic[3] == NFFS_AREA_MAGIC3;
}
int
nffs_area_is_scratch(const struct nffs_disk_area *disk_area)
{
return nffs_area_magic_is_set(disk_area) &&
disk_area->nda_id == NFFS_AREA_ID_NONE;
}
int
nffs_area_is_current_version(const struct nffs_disk_area *disk_area)
{
return disk_area->nda_ver == NFFS_AREA_VER;
}
void
nffs_area_to_disk(const struct nffs_area *area,
struct nffs_disk_area *out_disk_area)
{
memset(out_disk_area, 0, sizeof *out_disk_area);
nffs_area_set_magic(out_disk_area);
out_disk_area->nda_length = area->na_length;
out_disk_area->nda_ver = NFFS_AREA_VER;
out_disk_area->nda_gc_seq = area->na_gc_seq;
out_disk_area->nda_id = area->na_id;
}
uint32_t
nffs_area_free_space(const struct nffs_area *area)
{
return area->na_length - area->na_cur;
}
/**
* Finds a corrupt scratch area. An area is indentified as a corrupt scratch
* area if it and another area share the same ID. Among two areas with the
* same ID, the one with fewer bytes written is the corrupt scratch area.
*
* @param out_good_idx On success, the index of the good area (longer
* of the two areas) gets written here.
* @param out_bad_idx On success, the index of the corrupt scratch
* area gets written here.
*
* @return 0 if a corrupt scratch area was identified;
* FS_ENOENT if one was not found.
*/
int
nffs_area_find_corrupt_scratch(uint16_t *out_good_idx, uint16_t *out_bad_idx)
{
const struct nffs_area *iarea;
const struct nffs_area *jarea;
int i;
int j;
for (i = 0; i < nffs_num_areas; i++) {
iarea = nffs_areas + i;
for (j = i + 1; j < nffs_num_areas; j++) {
jarea = nffs_areas + j;
if (jarea->na_id == iarea->na_id) {
/* Found a duplicate. The shorter of the two areas should be
* used as scratch.
*/
if (iarea->na_cur < jarea->na_cur) {
*out_good_idx = j;
*out_bad_idx = i;
} else {
*out_good_idx = i;
*out_bad_idx = j;
}
return 0;
}
}
}
return FS_ENOENT;
}