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/*
* Copyright (C) 2012 The Android Open Source Project
*
* Licensed 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 <stdlib.h>
#include <sparse/sparse.h>
#include "defs.h"
#include "sparse_file.h"
#include "output_file.h"
#include "backed_block.h"
#include "sparse_defs.h"
#include "sparse_format.h"
struct sparse_file *sparse_file_new(unsigned int block_size, int64_t len)
{
struct sparse_file *s = calloc(sizeof(struct sparse_file), 1);
if (!s) {
return NULL;
}
s->backed_block_list = backed_block_list_new(block_size);
if (!s->backed_block_list) {
free(s);
return NULL;
}
s->block_size = block_size;
s->len = len;
return s;
}
void sparse_file_destroy(struct sparse_file *s)
{
backed_block_list_destroy(s->backed_block_list);
free(s);
}
int sparse_file_add_data(struct sparse_file *s,
void *data, unsigned int len, unsigned int block)
{
return backed_block_add_data(s->backed_block_list, data, len, block);
}
int sparse_file_add_fill(struct sparse_file *s,
uint32_t fill_val, unsigned int len, unsigned int block)
{
return backed_block_add_fill(s->backed_block_list, fill_val, len, block);
}
int sparse_file_add_file(struct sparse_file *s,
const char *filename, int64_t file_offset, unsigned int len,
unsigned int block)
{
return backed_block_add_file(s->backed_block_list, filename, file_offset,
len, block);
}
int sparse_file_add_fd(struct sparse_file *s,
int fd, int64_t file_offset, unsigned int len, unsigned int block)
{
return backed_block_add_fd(s->backed_block_list, fd, file_offset,
len, block);
}
unsigned int sparse_count_chunks(struct sparse_file *s)
{
struct backed_block *bb;
unsigned int last_block = 0;
unsigned int chunks = 0;
for (bb = backed_block_iter_new(s->backed_block_list); bb;
bb = backed_block_iter_next(bb)) {
if (backed_block_block(bb) > last_block) {
/* If there is a gap between chunks, add a skip chunk */
chunks++;
}
chunks++;
last_block = backed_block_block(bb) +
DIV_ROUND_UP(backed_block_len(bb), s->block_size);
}
if (last_block < DIV_ROUND_UP(s->len, s->block_size)) {
chunks++;
}
return chunks;
}
static void sparse_file_write_block(struct output_file *out,
struct backed_block *bb)
{
switch (backed_block_type(bb)) {
case BACKED_BLOCK_DATA:
write_data_chunk(out, backed_block_len(bb), backed_block_data(bb));
break;
case BACKED_BLOCK_FILE:
write_file_chunk(out, backed_block_len(bb),
backed_block_filename(bb), backed_block_file_offset(bb));
break;
case BACKED_BLOCK_FD:
write_fd_chunk(out, backed_block_len(bb),
backed_block_fd(bb), backed_block_file_offset(bb));
break;
case BACKED_BLOCK_FILL:
write_fill_chunk(out, backed_block_len(bb),
backed_block_fill_val(bb));
break;
}
}
static int write_all_blocks(struct sparse_file *s, struct output_file *out)
{
struct backed_block *bb;
unsigned int last_block = 0;
int64_t pad;
for (bb = backed_block_iter_new(s->backed_block_list); bb;
bb = backed_block_iter_next(bb)) {
if (backed_block_block(bb) > last_block) {
unsigned int blocks = backed_block_block(bb) - last_block;
write_skip_chunk(out, (int64_t)blocks * s->block_size);
}
sparse_file_write_block(out, bb);
last_block = backed_block_block(bb) +
DIV_ROUND_UP(backed_block_len(bb), s->block_size);
}
pad = s->len - (int64_t)last_block * s->block_size;
assert(pad >= 0);
if (pad > 0) {
write_skip_chunk(out, pad);
}
return 0;
}
int sparse_file_write(struct sparse_file *s, int fd, bool gz, bool sparse,
bool crc)
{
int ret;
int chunks;
struct output_file *out;
chunks = sparse_count_chunks(s);
out = output_file_open_fd(fd, s->block_size, s->len, gz, sparse, chunks, crc);
if (!out)
return -ENOMEM;
ret = write_all_blocks(s, out);
output_file_close(out);
return ret;
}
int sparse_file_callback(struct sparse_file *s, bool sparse, bool crc,
int (*write)(void *priv, const void *data, int len), void *priv)
{
int ret;
int chunks;
struct output_file *out;
chunks = sparse_count_chunks(s);
out = output_file_open_callback(write, priv, s->block_size, s->len, false,
sparse, chunks, crc);
if (!out)
return -ENOMEM;
ret = write_all_blocks(s, out);
output_file_close(out);
return ret;
}
static int out_counter_write(void *priv, const void *data __unused, int len)
{
int64_t *count = priv;
*count += len;
return 0;
}
int64_t sparse_file_len(struct sparse_file *s, bool sparse, bool crc)
{
int ret;
int chunks = sparse_count_chunks(s);
int64_t count = 0;
struct output_file *out;
out = output_file_open_callback(out_counter_write, &count,
s->block_size, s->len, false, sparse, chunks, crc);
if (!out) {
return -1;
}
ret = write_all_blocks(s, out);
output_file_close(out);
if (ret < 0) {
return -1;
}
return count;
}
static struct backed_block *move_chunks_up_to_len(struct sparse_file *from,
struct sparse_file *to, unsigned int len)
{
int64_t count = 0;
struct output_file *out_counter;
struct backed_block *last_bb = NULL;
struct backed_block *bb;
struct backed_block *start;
int64_t file_len = 0;
/*
* overhead is sparse file header, initial skip chunk, split chunk, end
* skip chunk, and crc chunk.
*/
int overhead = sizeof(sparse_header_t) + 4 * sizeof(chunk_header_t) +
sizeof(uint32_t);
len -= overhead;
start = backed_block_iter_new(from->backed_block_list);
out_counter = output_file_open_callback(out_counter_write, &count,
to->block_size, to->len, false, true, 0, false);
if (!out_counter) {
return NULL;
}
for (bb = start; bb; bb = backed_block_iter_next(bb)) {
count = 0;
/* will call out_counter_write to update count */
sparse_file_write_block(out_counter, bb);
if (file_len + count > len) {
/*
* If the remaining available size is more than 1/8th of the
* requested size, split the chunk. Results in sparse files that
* are at least 7/8ths of the requested size
*/
if (!last_bb || (len - file_len > (len / 8))) {
backed_block_split(from->backed_block_list, bb, len - file_len);
last_bb = bb;
}
goto out;
}
file_len += count;
last_bb = bb;
}
out:
backed_block_list_move(from->backed_block_list,
to->backed_block_list, start, last_bb);
output_file_close(out_counter);
return bb;
}
int sparse_file_resparse(struct sparse_file *in_s, unsigned int max_len,
struct sparse_file **out_s, int out_s_count)
{
struct backed_block *bb;
unsigned int overhead;
struct sparse_file *s;
struct sparse_file *tmp;
int c = 0;
tmp = sparse_file_new(in_s->block_size, in_s->len);
if (!tmp) {
return -ENOMEM;
}
do {
s = sparse_file_new(in_s->block_size, in_s->len);
bb = move_chunks_up_to_len(in_s, s, max_len);
if (c < out_s_count) {
out_s[c] = s;
} else {
backed_block_list_move(s->backed_block_list, tmp->backed_block_list,
NULL, NULL);
sparse_file_destroy(s);
}
c++;
} while (bb);
backed_block_list_move(tmp->backed_block_list, in_s->backed_block_list,
NULL, NULL);
sparse_file_destroy(tmp);
return c;
}
void sparse_file_verbose(struct sparse_file *s)
{
s->verbose = true;
}