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xz/src/liblzma/subblock/subblock_encoder.c

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///////////////////////////////////////////////////////////////////////////////
//
/// \file subblock_encoder.c
/// \brief Encoder of the Subblock filter
//
// Author: Lasse Collin
//
// This file has been put into the public domain.
// You can do whatever you want with this file.
//
///////////////////////////////////////////////////////////////////////////////
#include "subblock_encoder.h"
#include "filter_encoder.h"
/// Maximum number of repeats that a single Repeating Data can indicate.
/// This is directly from the file format specification.
#define REPEAT_COUNT_MAX (1U << 28)
/// Number of bytes the data chunk (not including the header part) must be
/// before we care about alignment. This is somewhat arbitrary. It just
/// doesn't make sense to waste bytes for alignment when the data chunk
/// is very small.
#define MIN_CHUNK_SIZE_FOR_ALIGN 4
/// Number of bytes of the header part of Subblock Type `Data'. This is
/// used as the `skew' argument for subblock_align().
#define ALIGN_SKEW_DATA 4
/// Like above but for Repeating Data.
#define ALIGN_SKEW_REPEATING_DATA 5
/// Writes one byte to output buffer and updates the alignment counter.
#define write_byte(b) \
do { \
assert(*out_pos < out_size); \
out[*out_pos] = b; \
++*out_pos; \
++coder->alignment.out_pos; \
} while (0)
struct lzma_coder_s {
lzma_next_coder next;
bool next_finished;
enum {
SEQ_FILL,
SEQ_FLUSH,
SEQ_RLE_COUNT_0,
SEQ_RLE_COUNT_1,
SEQ_RLE_COUNT_2,
SEQ_RLE_COUNT_3,
SEQ_RLE_SIZE,
SEQ_RLE_DATA,
SEQ_DATA_SIZE_0,
SEQ_DATA_SIZE_1,
SEQ_DATA_SIZE_2,
SEQ_DATA_SIZE_3,
SEQ_DATA,
SEQ_SUBFILTER_INIT,
SEQ_SUBFILTER_FLAGS,
} sequence;
/// Pointer to the options given by the application. This is used
/// for two-way communication with the application.
lzma_options_subblock *options;
/// Position in various arrays.
size_t pos;
/// Holds subblock.size - 1 or rle.size - 1 when encoding size
/// of Data or Repeat Count.
uint32_t tmp;
struct {
/// This is a copy of options->alignment, or
/// LZMA_SUBBLOCK_ALIGNMENT_DEFAULT if options is NULL.
uint32_t multiple;
/// Number of input bytes which we have processed and started
/// writing out. 32-bit integer is enough since we care only
/// about the lowest bits when fixing alignment.
uint32_t in_pos;
/// Number of bytes written out.
uint32_t out_pos;
} alignment;
struct {
/// Pointer to allocated buffer holding the Data field
/// of Subblock Type "Data".
uint8_t *data;
/// Number of bytes in the buffer.
size_t size;
/// Allocated size of the buffer.
size_t limit;
/// Number of input bytes that we have already read but
/// not yet started writing out. This can be different
/// to `size' when using Subfilter. That's why we track
/// in_pending separately for RLE (see below).
uint32_t in_pending;
} subblock;
struct {
/// Buffer to hold the data that may be coded with
/// Subblock Type `Repeating Data'.
uint8_t buffer[LZMA_SUBBLOCK_RLE_MAX];
/// Number of bytes in buffer[].
size_t size;
/// Number of times the first `size' bytes of buffer[]
/// will be repeated.
uint64_t count;
/// Like subblock.in_pending above, but for RLE.
uint32_t in_pending;
} rle;
struct {
enum {
SUB_NONE,
SUB_SET,
SUB_RUN,
SUB_FLUSH,
SUB_FINISH,
SUB_END_MARKER,
} mode;
/// This is a copy of options->allow_subfilters. We use
/// this to verify that the application doesn't change
/// the value of allow_subfilters.
bool allow;
/// When this is true, application is not allowed to modify
/// options->subblock_mode. We may still modify it here.
bool mode_locked;
/// True if we have encoded at least one byte of data with
/// the Subfilter.
bool got_input;
/// Track the amount of input available once
/// LZMA_SUBFILTER_FINISH has been enabled.
/// This is needed for sanity checking (kind
/// of duplicating what common/code.c does).
size_t in_avail;
/// Buffer for the Filter Flags field written after
/// the `Set Subfilter' indicator.
uint8_t *flags;
/// Size of Filter Flags field.
uint32_t flags_size;
/// Pointers to Subfilter.
lzma_next_coder subcoder;
} subfilter;
/// Temporary buffer used when we are not the last filter in the chain.
struct {
size_t pos;
size_t size;
uint8_t buffer[LZMA_BUFFER_SIZE];
} temp;
};
/// \brief Aligns the output buffer
///
/// Aligns the output buffer so that after skew bytes the output position is
/// a multiple of coder->alignment.multiple.
static bool
subblock_align(lzma_coder *coder, uint8_t *restrict out,
size_t *restrict out_pos, size_t out_size,
size_t chunk_size, uint32_t skew)
{
assert(*out_pos < out_size);
// Fix the alignment only if it makes sense at least a little.
if (chunk_size >= MIN_CHUNK_SIZE_FOR_ALIGN) {
const uint32_t target = coder->alignment.in_pos
% coder->alignment.multiple;
while ((coder->alignment.out_pos + skew)
% coder->alignment.multiple != target) {
// Zero indicates padding.
write_byte(0x00);
// Check if output buffer got full and indicate it to
// the caller.
if (*out_pos == out_size)
return true;
}
}
// Output buffer is not full.
return false;
}
/// \brief Checks if buffer contains repeated data
///
/// \param needle Buffer containing a single repeat chunk
/// \param needle_size Size of needle in bytes
/// \param buf Buffer to search for repeated needles
/// \param buf_chunks Buffer size is buf_chunks * needle_size.
///
/// \return True if the whole buf is filled with repeated needles.
///
static bool
is_repeating(const uint8_t *restrict needle, size_t needle_size,
const uint8_t *restrict buf, size_t buf_chunks)
{
while (buf_chunks-- != 0) {
if (memcmp(buf, needle, needle_size) != 0)
return false;
buf += needle_size;
}
return true;
}
/// \brief Optimizes the repeating style and updates coder->sequence
static void
subblock_rle_flush(lzma_coder *coder)
{
// The Subblock decoder can use memset() when the size of the data
// being repeated is one byte, so we check if the RLE buffer is
// filled with a single repeating byte.
if (coder->rle.size > 1) {
const uint8_t b = coder->rle.buffer[0];
size_t i = 0;
while (true) {
if (coder->rle.buffer[i] != b)
break;
if (++i == coder->rle.size) {
// TODO Integer overflow check maybe,
// although this needs at least 2**63 bytes
// of input until it gets triggered...
coder->rle.count *= coder->rle.size;
coder->rle.size = 1;
break;
}
}
}
if (coder->rle.count == 1) {
// The buffer should be repeated only once. It is
// waste of space to use Repeating Data. Instead,
// write a regular Data Subblock. See SEQ_RLE_COUNT_0
// in subblock_buffer() for more info.
coder->tmp = coder->rle.size - 1;
} else if (coder->rle.count > REPEAT_COUNT_MAX) {
// There's so much to repeat that it doesn't fit into
// 28-bit integer. We will write two or more Subblocks
// of type Repeating Data.
coder->tmp = REPEAT_COUNT_MAX - 1;
} else {
coder->tmp = coder->rle.count - 1;
}
coder->sequence = SEQ_RLE_COUNT_0;
return;
}
/// \brief Resizes coder->subblock.data for a new size limit
static lzma_ret
subblock_data_size(lzma_coder *coder, lzma_allocator *allocator,
size_t new_limit)
{
// Verify that the new limit is valid.
if (new_limit < LZMA_SUBBLOCK_DATA_SIZE_MIN
|| new_limit > LZMA_SUBBLOCK_DATA_SIZE_MAX)
return LZMA_OPTIONS_ERROR;
// Ff the new limit is different than the previous one, we need
// to reallocate the data buffer.
if (new_limit != coder->subblock.limit) {
lzma_free(coder->subblock.data, allocator);
coder->subblock.data = lzma_alloc(new_limit, allocator);
if (coder->subblock.data == NULL)
return LZMA_MEM_ERROR;
}
coder->subblock.limit = new_limit;
return LZMA_OK;
}
static lzma_ret
subblock_buffer(lzma_coder *coder, lzma_allocator *allocator,
const uint8_t *restrict in, size_t *restrict in_pos,
size_t in_size, uint8_t *restrict out,
size_t *restrict out_pos, size_t out_size, lzma_action action)
{
// Changing allow_subfilter is not allowed.
if (coder->options != NULL && coder->subfilter.allow
!= coder->options->allow_subfilters)
return LZMA_PROG_ERROR;
// Check if we need to do something special with the Subfilter.
if (coder->subfilter.allow) {
assert(coder->options != NULL);
// See if subfilter_mode has been changed.
switch (coder->options->subfilter_mode) {
case LZMA_SUBFILTER_NONE:
if (coder->subfilter.mode != SUB_NONE)
return LZMA_PROG_ERROR;
break;
case LZMA_SUBFILTER_SET:
if (coder->subfilter.mode_locked
|| coder->subfilter.mode != SUB_NONE)
return LZMA_PROG_ERROR;
coder->subfilter.mode = SUB_SET;
coder->subfilter.got_input = false;
if (coder->sequence == SEQ_FILL)
coder->sequence = SEQ_FLUSH;
break;
case LZMA_SUBFILTER_RUN:
if (coder->subfilter.mode != SUB_RUN)
return LZMA_PROG_ERROR;
break;
case LZMA_SUBFILTER_FINISH: {
const size_t in_avail = in_size - *in_pos;
if (coder->subfilter.mode == SUB_RUN) {
if (coder->subfilter.mode_locked)
return LZMA_PROG_ERROR;
coder->subfilter.mode = SUB_FINISH;
coder->subfilter.in_avail = in_avail;
} else if (coder->subfilter.mode != SUB_FINISH
|| coder->subfilter.in_avail
!= in_avail) {
return LZMA_PROG_ERROR;
}
break;
}
default:
return LZMA_OPTIONS_ERROR;
}
// If we are sync-flushing or finishing, the application may
// no longer change subfilter_mode. Note that this check is
// done after checking the new subfilter_mode above; this
// way the application may e.g. set LZMA_SUBFILTER_SET and
// LZMA_SYNC_FLUSH at the same time, but it cannot modify
// subfilter_mode on the later lzma_code() calls before
// we have returned LZMA_STREAM_END.
if (action != LZMA_RUN)
coder->subfilter.mode_locked = true;
}
// Main loop
while (*out_pos < out_size)
switch (coder->sequence) {
case SEQ_FILL:
// Grab the new Subblock Data Size and reallocate the buffer.
if (coder->subblock.size == 0 && coder->options != NULL
&& coder->options->subblock_data_size
!= coder->subblock.limit)
return_if_error(subblock_data_size(coder,
allocator, coder->options
->subblock_data_size));
if (coder->subfilter.mode == SUB_NONE) {
assert(coder->subfilter.subcoder.code == NULL);
// No Subfilter is enabled, just copy the data as is.
coder->subblock.in_pending += lzma_bufcpy(
in, in_pos, in_size,
coder->subblock.data,
&coder->subblock.size,
coder->subblock.limit);
// If we ran out of input before the whole buffer
// was filled, return to application.
if (coder->subblock.size < coder->subblock.limit
&& action == LZMA_RUN)
return LZMA_OK;
} else {
assert(coder->options->subfilter_mode
!= LZMA_SUBFILTER_SET);
// Using LZMA_FINISH automatically toggles
// LZMA_SUBFILTER_FINISH.
//
// NOTE: It is possible that application had set
// LZMA_SUBFILTER_SET and LZMA_FINISH at the same
// time. In that case it is possible that we will
// cycle to LZMA_SUBFILTER_RUN, LZMA_SUBFILTER_FINISH,
// and back to LZMA_SUBFILTER_NONE in a single
// Subblock encoder function call.
if (action == LZMA_FINISH) {
coder->options->subfilter_mode
= LZMA_SUBFILTER_FINISH;
coder->subfilter.mode = SUB_FINISH;
}
const size_t in_start = *in_pos;
const lzma_ret ret = coder->subfilter.subcoder.code(
coder->subfilter.subcoder.coder,
allocator, in, in_pos, in_size,
coder->subblock.data,
&coder->subblock.size,
coder->subblock.limit,
coder->subfilter.mode == SUB_FINISH
? LZMA_FINISH : action);
const size_t in_used = *in_pos - in_start;
coder->subblock.in_pending += in_used;
if (in_used > 0)
coder->subfilter.got_input = true;
coder->subfilter.in_avail = in_size - *in_pos;
if (ret == LZMA_STREAM_END) {
// All currently available input must have
// been processed.
assert(*in_pos == in_size);
// Flush now. Even if coder->subblock.size
// happened to be zero, we still need to go
// to SEQ_FLUSH to possibly finish RLE or
// write the Subfilter Unset indicator.
coder->sequence = SEQ_FLUSH;
if (coder->subfilter.mode == SUB_RUN) {
// Flushing with Subfilter enabled.
assert(action == LZMA_SYNC_FLUSH);
coder->subfilter.mode = SUB_FLUSH;
break;
}
// Subfilter finished its job.
assert(coder->subfilter.mode == SUB_FINISH
|| action == LZMA_FINISH);
// At least one byte of input must have been
// encoded with the Subfilter. This is
// required by the file format specification.
if (!coder->subfilter.got_input)
return LZMA_PROG_ERROR;
// We don't strictly need to do this, but
// doing it sounds like a good idea, because
// otherwise the Subfilter's memory could be
// left allocated for long time, and would
// just waste memory.
lzma_next_end(&coder->subfilter.subcoder,
allocator);
// We need to flush the currently buffered
// data and write Unset Subfilter marker.
// Note that we cannot set
// coder->options->subfilter_mode to
// LZMA_SUBFILTER_NONE yet, because we
// haven't written the Unset Subfilter
// marker yet.
coder->subfilter.mode = SUB_END_MARKER;
coder->sequence = SEQ_FLUSH;
break;
}
// Return if we couldn't fill the buffer or
// if an error occurred.
if (coder->subblock.size < coder->subblock.limit
|| ret != LZMA_OK)
return ret;
}
coder->sequence = SEQ_FLUSH;
// SEQ_FILL doesn't produce any output so falling through
// to SEQ_FLUSH is safe.
assert(*out_pos < out_size);
// Fall through
case SEQ_FLUSH:
if (coder->options != NULL) {
// Update the alignment variable.
coder->alignment.multiple = coder->options->alignment;
if (coder->alignment.multiple
< LZMA_SUBBLOCK_ALIGNMENT_MIN
|| coder->alignment.multiple
> LZMA_SUBBLOCK_ALIGNMENT_MAX)
return LZMA_OPTIONS_ERROR;
// Run-length encoder
//
// First check if there is some data pending and we
// have an obvious need to flush it immediately.
if (coder->rle.count > 0
&& (coder->rle.size
!= coder->options->rle
|| coder->subblock.size
% coder->rle.size)) {
subblock_rle_flush(coder);
break;
}
// Grab the (possibly new) RLE chunk size and
// validate it.
coder->rle.size = coder->options->rle;
if (coder->rle.size > LZMA_SUBBLOCK_RLE_MAX)
return LZMA_OPTIONS_ERROR;
if (coder->subblock.size != 0
&& coder->rle.size
!= LZMA_SUBBLOCK_RLE_OFF
&& coder->subblock.size
% coder->rle.size == 0) {
// Initialize coder->rle.buffer if we don't
// have RLE already running.
if (coder->rle.count == 0)
memcpy(coder->rle.buffer,
coder->subblock.data,
coder->rle.size);
// Test if coder->subblock.data is repeating.
// If coder->rle.count would overflow, we
// force flushing. Forced flushing shouldn't
// really happen in real-world situations.
const size_t count = coder->subblock.size
/ coder->rle.size;
if (UINT64_MAX - count > coder->rle.count
&& is_repeating(
coder->rle.buffer,
coder->rle.size,
coder->subblock.data,
count)) {
coder->rle.count += count;
coder->rle.in_pending += coder
->subblock.in_pending;
coder->subblock.in_pending = 0;
coder->subblock.size = 0;
} else if (coder->rle.count > 0) {
// It's not repeating or at least not
// with the same byte sequence as the
// earlier Subblock Data buffers. We
// have some data pending in the RLE
// buffer already, so do a flush.
// Once flushed, we will check again
// if the Subblock Data happens to
// contain a different repeating
// sequence.
subblock_rle_flush(coder);
break;
}
}
}
// If we now have some data left in coder->subblock, the RLE
// buffer is empty and we must write a regular Subblock Data.
if (coder->subblock.size > 0) {
assert(coder->rle.count == 0);
coder->tmp = coder->subblock.size - 1;
coder->sequence = SEQ_DATA_SIZE_0;
break;
}
// Check if we should enable Subfilter.
if (coder->subfilter.mode == SUB_SET) {
if (coder->rle.count > 0)
subblock_rle_flush(coder);
else
coder->sequence = SEQ_SUBFILTER_INIT;
break;
}
// Check if we have just finished Subfiltering.
if (coder->subfilter.mode == SUB_END_MARKER) {
if (coder->rle.count > 0) {
subblock_rle_flush(coder);
break;
}
coder->options->subfilter_mode = LZMA_SUBFILTER_NONE;
coder->subfilter.mode = SUB_NONE;
write_byte(0x50);
if (*out_pos == out_size)
return LZMA_OK;
}
// Check if we have already written everything.
if (action != LZMA_RUN && *in_pos == in_size
&& (coder->subfilter.mode == SUB_NONE
|| coder->subfilter.mode == SUB_FLUSH)) {
if (coder->rle.count > 0) {
subblock_rle_flush(coder);
break;
}
if (action == LZMA_SYNC_FLUSH) {
if (coder->subfilter.mode == SUB_FLUSH)
coder->subfilter.mode = SUB_RUN;
coder->subfilter.mode_locked = false;
coder->sequence = SEQ_FILL;
} else {
assert(action == LZMA_FINISH);
// Write EOPM.
// NOTE: No need to use write_byte() here
// since we are finishing.
out[*out_pos] = 0x10;
++*out_pos;
}
return LZMA_STREAM_END;
}
// Otherwise we have more work to do.
coder->sequence = SEQ_FILL;
break;
case SEQ_RLE_COUNT_0:
assert(coder->rle.count > 0);
if (coder->rle.count == 1) {
// The buffer should be repeated only once. Fix
// the alignment and write the first byte of
// Subblock Type `Data'.
if (subblock_align(coder, out, out_pos, out_size,
coder->rle.size, ALIGN_SKEW_DATA))
return LZMA_OK;
write_byte(0x20 | (coder->tmp & 0x0F));
} else {
// We have something to actually repeat, which should
// mean that it takes less space with run-length
// encoding.
if (subblock_align(coder, out, out_pos, out_size,
coder->rle.size,
ALIGN_SKEW_REPEATING_DATA))
return LZMA_OK;
write_byte(0x30 | (coder->tmp & 0x0F));
}
// NOTE: If we have to write more than one Repeating Data
// due to rle.count > REPEAT_COUNT_MAX, the subsequent
// Repeating Data Subblocks may get wrong alignment, because
// we add rle.in_pending to alignment.in_pos at once instead
// of adding only as much as this particular Repeating Data
// consumed input data. Correct alignment is always restored
// after all the required Repeating Data Subblocks have been
// written. This problem occurs in such a weird cases that
// it's not worth fixing.
coder->alignment.out_pos += coder->rle.size;
coder->alignment.in_pos += coder->rle.in_pending;
coder->rle.in_pending = 0;
coder->sequence = SEQ_RLE_COUNT_1;
break;
case SEQ_RLE_COUNT_1:
write_byte(coder->tmp >> 4);
coder->sequence = SEQ_RLE_COUNT_2;
break;
case SEQ_RLE_COUNT_2:
write_byte(coder->tmp >> 12);
coder->sequence = SEQ_RLE_COUNT_3;
break;
case SEQ_RLE_COUNT_3:
write_byte(coder->tmp >> 20);
// Again, see if we are writing regular Data or Repeating Data.
// In the former case, we skip SEQ_RLE_SIZE.
if (coder->rle.count == 1)
coder->sequence = SEQ_RLE_DATA;
else
coder->sequence = SEQ_RLE_SIZE;
if (coder->rle.count > REPEAT_COUNT_MAX)
coder->rle.count -= REPEAT_COUNT_MAX;
else
coder->rle.count = 0;
break;
case SEQ_RLE_SIZE:
assert(coder->rle.size >= LZMA_SUBBLOCK_RLE_MIN);
assert(coder->rle.size <= LZMA_SUBBLOCK_RLE_MAX);
write_byte(coder->rle.size - 1);
coder->sequence = SEQ_RLE_DATA;
break;
case SEQ_RLE_DATA:
lzma_bufcpy(coder->rle.buffer, &coder->pos, coder->rle.size,
out, out_pos, out_size);
if (coder->pos < coder->rle.size)
return LZMA_OK;
coder->pos = 0;
coder->sequence = SEQ_FLUSH;
break;
case SEQ_DATA_SIZE_0:
// We need four bytes for the Size field.
if (subblock_align(coder, out, out_pos, out_size,
coder->subblock.size, ALIGN_SKEW_DATA))
return LZMA_OK;
coder->alignment.out_pos += coder->subblock.size;
coder->alignment.in_pos += coder->subblock.in_pending;
coder->subblock.in_pending = 0;
write_byte(0x20 | (coder->tmp & 0x0F));
coder->sequence = SEQ_DATA_SIZE_1;
break;
case SEQ_DATA_SIZE_1:
write_byte(coder->tmp >> 4);
coder->sequence = SEQ_DATA_SIZE_2;
break;
case SEQ_DATA_SIZE_2:
write_byte(coder->tmp >> 12);
coder->sequence = SEQ_DATA_SIZE_3;
break;
case SEQ_DATA_SIZE_3:
write_byte(coder->tmp >> 20);
coder->sequence = SEQ_DATA;
break;
case SEQ_DATA:
lzma_bufcpy(coder->subblock.data, &coder->pos,
coder->subblock.size, out, out_pos, out_size);
if (coder->pos < coder->subblock.size)
return LZMA_OK;
coder->subblock.size = 0;
coder->pos = 0;
coder->sequence = SEQ_FLUSH;
break;
case SEQ_SUBFILTER_INIT: {
assert(coder->subblock.size == 0);
assert(coder->subblock.in_pending == 0);
assert(coder->rle.count == 0);
assert(coder->rle.in_pending == 0);
assert(coder->subfilter.mode == SUB_SET);
assert(coder->options != NULL);
// There must be a filter specified.
if (coder->options->subfilter_options.id == LZMA_VLI_UNKNOWN)
return LZMA_OPTIONS_ERROR;
// Initialize a raw encoder to work as a Subfilter.
lzma_filter options[2];
options[0] = coder->options->subfilter_options;
options[1].id = LZMA_VLI_UNKNOWN;
return_if_error(lzma_raw_encoder_init(
&coder->subfilter.subcoder, allocator,
options));
// Encode the Filter Flags field into a buffer. This should
// never fail since we have already successfully initialized
// the Subfilter itself. Check it still, and return
// LZMA_PROG_ERROR instead of whatever the ret would say.
lzma_ret ret = lzma_filter_flags_size(
&coder->subfilter.flags_size, options);
assert(ret == LZMA_OK);
if (ret != LZMA_OK)
return LZMA_PROG_ERROR;
coder->subfilter.flags = lzma_alloc(
coder->subfilter.flags_size, allocator);
if (coder->subfilter.flags == NULL)
return LZMA_MEM_ERROR;
// Now we have a big-enough buffer. Encode the Filter Flags.
// Like above, this should never fail.
size_t dummy = 0;
ret = lzma_filter_flags_encode(options, coder->subfilter.flags,
&dummy, coder->subfilter.flags_size);
assert(ret == LZMA_OK);
assert(dummy == coder->subfilter.flags_size);
if (ret != LZMA_OK || dummy != coder->subfilter.flags_size)
return LZMA_PROG_ERROR;
// Write a Subblock indicating a new Subfilter.
write_byte(0x40);
coder->options->subfilter_mode = LZMA_SUBFILTER_RUN;
coder->subfilter.mode = SUB_RUN;
coder->alignment.out_pos += coder->subfilter.flags_size;
coder->sequence = SEQ_SUBFILTER_FLAGS;
// It is safe to fall through because SEQ_SUBFILTER_FLAGS
// uses lzma_bufcpy() which doesn't write unless there is
// output space.
}
// Fall through
case SEQ_SUBFILTER_FLAGS:
// Copy the Filter Flags to the output stream.
lzma_bufcpy(coder->subfilter.flags, &coder->pos,
coder->subfilter.flags_size,
out, out_pos, out_size);
if (coder->pos < coder->subfilter.flags_size)
return LZMA_OK;
lzma_free(coder->subfilter.flags, allocator);
coder->subfilter.flags = NULL;
coder->pos = 0;
coder->sequence = SEQ_FILL;
break;
default:
return LZMA_PROG_ERROR;
}
return LZMA_OK;
}
static lzma_ret
subblock_encode(lzma_coder *coder, lzma_allocator *allocator,
const uint8_t *restrict in, size_t *restrict in_pos,
size_t in_size, uint8_t *restrict out,
size_t *restrict out_pos, size_t out_size, lzma_action action)
{
if (coder->next.code == NULL)
return subblock_buffer(coder, allocator, in, in_pos, in_size,
out, out_pos, out_size, action);
while (*out_pos < out_size
&& (*in_pos < in_size || action != LZMA_RUN)) {
if (!coder->next_finished
&& coder->temp.pos == coder->temp.size) {
coder->temp.pos = 0;
coder->temp.size = 0;
const lzma_ret ret = coder->next.code(coder->next.coder,
allocator, in, in_pos, in_size,
coder->temp.buffer, &coder->temp.size,
LZMA_BUFFER_SIZE, action);
if (ret == LZMA_STREAM_END) {
assert(action != LZMA_RUN);
coder->next_finished = true;
} else if (coder->temp.size == 0 || ret != LZMA_OK) {
return ret;
}
}
const lzma_ret ret = subblock_buffer(coder, allocator,
coder->temp.buffer, &coder->temp.pos,
coder->temp.size, out, out_pos, out_size,
coder->next_finished ? LZMA_FINISH : LZMA_RUN);
if (ret == LZMA_STREAM_END) {
assert(action != LZMA_RUN);
assert(coder->next_finished);
return LZMA_STREAM_END;
}
if (ret != LZMA_OK)
return ret;
}
return LZMA_OK;
}
static void
subblock_encoder_end(lzma_coder *coder, lzma_allocator *allocator)
{
lzma_next_end(&coder->next, allocator);
lzma_next_end(&coder->subfilter.subcoder, allocator);
lzma_free(coder->subblock.data, allocator);
lzma_free(coder->subfilter.flags, allocator);
lzma_free(coder, allocator);
return;
}
extern lzma_ret
lzma_subblock_encoder_init(lzma_next_coder *next, lzma_allocator *allocator,
const lzma_filter_info *filters)
{
if (next->coder == NULL) {
next->coder = lzma_alloc(sizeof(lzma_coder), allocator);
if (next->coder == NULL)
return LZMA_MEM_ERROR;
next->code = &subblock_encode;
next->end = &subblock_encoder_end;
next->coder->next = LZMA_NEXT_CODER_INIT;
next->coder->subblock.data = NULL;
next->coder->subblock.limit = 0;
next->coder->subfilter.subcoder = LZMA_NEXT_CODER_INIT;
} else {
lzma_next_end(&next->coder->subfilter.subcoder,
allocator);
lzma_free(next->coder->subfilter.flags, allocator);
}
next->coder->subfilter.flags = NULL;
next->coder->next_finished = false;
next->coder->sequence = SEQ_FILL;
next->coder->options = filters[0].options;
next->coder->pos = 0;
next->coder->alignment.in_pos = 0;
next->coder->alignment.out_pos = 0;
next->coder->subblock.size = 0;
next->coder->subblock.in_pending = 0;
next->coder->rle.count = 0;
next->coder->rle.in_pending = 0;
next->coder->subfilter.mode = SUB_NONE;
next->coder->subfilter.mode_locked = false;
next->coder->temp.pos = 0;
next->coder->temp.size = 0;
// Grab some values from the options structure if it is available.
size_t subblock_size_limit;
if (next->coder->options != NULL) {
if (next->coder->options->alignment
< LZMA_SUBBLOCK_ALIGNMENT_MIN
|| next->coder->options->alignment
> LZMA_SUBBLOCK_ALIGNMENT_MAX) {
subblock_encoder_end(next->coder, allocator);
return LZMA_OPTIONS_ERROR;
}
next->coder->alignment.multiple
= next->coder->options->alignment;
next->coder->subfilter.allow
= next->coder->options->allow_subfilters;
subblock_size_limit = next->coder->options->subblock_data_size;
} else {
next->coder->alignment.multiple
= LZMA_SUBBLOCK_ALIGNMENT_DEFAULT;
next->coder->subfilter.allow = false;
subblock_size_limit = LZMA_SUBBLOCK_DATA_SIZE_DEFAULT;
}
return_if_error(subblock_data_size(next->coder, allocator,
subblock_size_limit));
return lzma_next_filter_init(
&next->coder->next, allocator, filters + 1);
}
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