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/* SPDX-License-Identifier: GPL-3.0-or-later */
/*
* read_table.c
*
* Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
*/
#include "config.h"
#include "meta_reader.h"
#include "highlevel.h"
#include "util.h"
#include <endian.h>
#include <stdlib.h>
#include <stdio.h>
void *sqfs_read_table(int fd, compressor_t *cmp, size_t table_size,
uint64_t location)
{
size_t diff, block_count, list_size, blk_idx = 0;
uint64_t start, *locations;
meta_reader_t *m;
void *data, *ptr;
data = malloc(table_size);
if (data == NULL) {
perror("reading table");
return NULL;
}
/* restore list from image */
block_count = table_size / SQFS_META_BLOCK_SIZE;
if ((table_size % SQFS_META_BLOCK_SIZE) != 0)
++block_count;
list_size = sizeof(uint64_t) * block_count;
locations = malloc(list_size);
if (locations == NULL) {
perror("allocation table location list");
goto fail_data;
}
if (read_data_at("reading table locations", location,
fd, locations, list_size)) {
goto fail_idx;
}
/* Read the actual data */
m = meta_reader_create(fd, cmp);
if (m == NULL)
goto fail_idx;
ptr = data;
while (table_size > 0) {
start = le64toh(locations[blk_idx++]);
if (meta_reader_seek(m, start, 0))
goto fail;
diff = SQFS_META_BLOCK_SIZE;
if (diff > table_size)
diff = table_size;
if (meta_reader_read(m, ptr, diff))
goto fail;
ptr = (char *)ptr + diff;
table_size -= diff;
}
meta_reader_destroy(m);
free(locations);
return data;
fail:
meta_reader_destroy(m);
fail_idx:
free(locations);
fail_data:
free(data);
return NULL;
}
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