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/* SPDX-License-Identifier: GPL-3.0-or-later */
#include "meta_reader.h"
#include "highlevel.h"
#include "util.h"
#include <stdlib.h>
#include <unistd.h>
#include <stdio.h>
int id_table_read(id_table_t *tbl, int fd, sqfs_super_t *super,
compressor_t *cmp)
{
size_t i, block_count, count, diff;
uint64_t blocks[32];
meta_reader_t *m;
uint32_t *ptr;
ssize_t ret;
if (tbl->ids != NULL) {
free(tbl->ids);
tbl->num_ids = 0;
tbl->max_ids = 0;
tbl->ids = NULL;
}
if (!super->id_count || super->id_table_start >= super->bytes_used) {
fputs("ID table missing from file system\n", stderr);
return -1;
}
tbl->ids = malloc(super->id_count * sizeof(uint32_t));
if (tbl->ids == NULL) {
perror("reading ID table");
return -1;
}
tbl->num_ids = super->id_count;
tbl->max_ids = super->id_count;
if (lseek(fd, super->id_table_start, SEEK_SET) == (off_t)-1)
goto fail_seek;
block_count = super->id_count / 2048;
if (super->id_count % 2048)
++block_count;
ret = read_retry(fd, blocks, sizeof(blocks[0]) * block_count);
if (ret < 0)
goto fail_rd;
if ((size_t)ret < sizeof(blocks[0]) * block_count)
goto fail_trunc;
for (i = 0; i < block_count; ++i)
blocks[i] = le64toh(blocks[i]);
m = meta_reader_create(fd, cmp);
if (m == NULL)
return -1;
count = super->id_count;
ptr = tbl->ids;
for (i = 0; i < block_count && count > 0; ++i) {
diff = count < 2048 ? count : 2048;
if (meta_reader_seek(m, blocks[i], 0))
goto fail_meta;
if (meta_reader_read(m, ptr, diff * sizeof(tbl->ids[0])))
goto fail_meta;
count -= diff;
ptr += diff;
}
meta_reader_destroy(m);
for (i = 0; i < tbl->num_ids; ++i)
tbl->ids[i] = le32toh(tbl->ids[i]);
return 0;
fail_meta:
meta_reader_destroy(m);
return -1;
fail_trunc:
fputs("reading ID table: unexpected end of file\n", stderr);
return -1;
fail_rd:
perror("reading ID table");
return -1;
fail_seek:
perror("seeking to ID table");
return -1;
}
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