lzma_filter_flags_decode(
lzma_filter *filter, lzma_allocator *allocator,
const uint8_t *in, size_t *in_pos, size_t in_size)
{
lzma_vli props_size;
lzma_ret ret;
// Set the pointer to NULL so the caller can always safely free it.
filter->options = NULL;
// Filter ID
return_if_error(lzma_vli_decode(&filter->id, NULL,
in, in_pos, in_size));
if (filter->id >= LZMA_FILTER_RESERVED_START)
return LZMA_DATA_ERROR;
// Size of Properties
return_if_error(lzma_vli_decode(&props_size, NULL,
in, in_pos, in_size));
// Filter Properties
if (in_size - *in_pos < props_size)
return LZMA_DATA_ERROR;
ret = lzma_properties_decode(
filter, allocator, in + *in_pos, props_size);
*in_pos += props_size;
return ret;
}
lzma_block_header_encode(const lzma_block *block, uint8_t *out)
{
// Validate everything but filters.
if (lzma_block_unpadded_size(block) == 0
|| !lzma_vli_is_valid(block->uncompressed_size))
return LZMA_PROG_ERROR;
// Indicate the size of the buffer _excluding_ the CRC32 field.
const size_t out_size = block->header_size - 4;
// Store the Block Header Size.
out[0] = out_size / 4;
// We write Block Flags in pieces.
out[1] = 0x00;
size_t out_pos = 2;
// Compressed Size
if (block->compressed_size != LZMA_VLI_UNKNOWN) {
return_if_error(lzma_vli_encode(block->compressed_size, NULL,
out, &out_pos, out_size));
out[1] |= 0x40;
}
// Uncompressed Size
if (block->uncompressed_size != LZMA_VLI_UNKNOWN) {
return_if_error(lzma_vli_encode(block->uncompressed_size, NULL,
out, &out_pos, out_size));
out[1] |= 0x80;
}
// Filter Flags
if (block->filters == NULL || block->filters[0].id == LZMA_VLI_UNKNOWN)
return LZMA_PROG_ERROR;
size_t filter_count = 0;
do {
// There can be a maximum of four filters.
if (filter_count == LZMA_FILTERS_MAX)
return LZMA_PROG_ERROR;
return_if_error(lzma_filter_flags_encode(
block->filters + filter_count,
out, &out_pos, out_size));
} while (block->filters[++filter_count].id != LZMA_VLI_UNKNOWN);
out[1] |= filter_count - 1;
// Padding
memzero(out + out_pos, out_size - out_pos);
// CRC32
unaligned_write32le(out + out_size, lzma_crc32(out, out_size, 0));
return LZMA_OK;
}
lzma_block_header_size(lzma_block *block)
{
if (block->version != 0)
return LZMA_OPTIONS_ERROR;
// Block Header Size + Block Flags + CRC32.
uint32_t size = 1 + 1 + 4;
// Compressed Size
if (block->compressed_size != LZMA_VLI_UNKNOWN) {
const uint32_t add = lzma_vli_size(block->compressed_size);
if (add == 0 || block->compressed_size == 0)
return LZMA_PROG_ERROR;
size += add;
}
// Uncompressed Size
if (block->uncompressed_size != LZMA_VLI_UNKNOWN) {
const uint32_t add = lzma_vli_size(block->uncompressed_size);
if (add == 0)
return LZMA_PROG_ERROR;
size += add;
}
// List of Filter Flags
if (block->filters == NULL || block->filters[0].id == LZMA_VLI_UNKNOWN)
return LZMA_PROG_ERROR;
for (size_t i = 0; block->filters[i].id != LZMA_VLI_UNKNOWN; ++i) {
// Don't allow too many filters.
if (i == LZMA_FILTERS_MAX)
return LZMA_PROG_ERROR;
uint32_t add;
return_if_error(lzma_filter_flags_size(&add,
block->filters + i));
size += add;
}
// Pad to a multiple of four bytes.
block->header_size = (size + 3) & ~UINT32_C(3);
// NOTE: We don't verify that the encoded size of the Block stays
// within limits. This is because it is possible that we are called
// with exaggerated Compressed Size (e.g. LZMA_VLI_MAX) to reserve
// space for Block Header, and later called again with lower,
// real values.
return LZMA_OK;
}
extern lzma_ret
lzma_raw_coder_init(lzma_next_coder *next, lzma_allocator *allocator,
const lzma_filter *options,
lzma_filter_find coder_find, bool is_encoder)
{
// Do some basic validation and get the number of filters.
size_t count;
return_if_error(validate_chain(options, &count));
// Set the filter functions and copy the options pointer.
lzma_filter_info filters[LZMA_FILTERS_MAX + 1];
if (is_encoder) {
for (size_t i = 0; i < count; ++i) {
// The order of the filters is reversed in the
// encoder. It allows more efficient handling
// of the uncompressed data.
const size_t j = count - i - 1;
const lzma_filter_coder *const fc
= coder_find(options[i].id);
if (fc == NULL || fc->init == NULL)
return LZMA_OPTIONS_ERROR;
filters[j].id = options[i].id;
filters[j].init = fc->init;
filters[j].options = options[i].options;
}
} else {
for (size_t i = 0; i < count; ++i) {
const lzma_filter_coder *const fc
= coder_find(options[i].id);
if (fc == NULL || fc->init == NULL)
return LZMA_OPTIONS_ERROR;
filters[i].id = options[i].id;
filters[i].init = fc->init;
filters[i].options = options[i].options;
}
}
// Terminate the array.
filters[count].id = LZMA_VLI_UNKNOWN;
filters[count].init = NULL;
// Initialize the filters.
const lzma_ret ret = lzma_next_filter_init(next, allocator, filters);
if (ret != LZMA_OK)
lzma_next_end(next, allocator);
return ret;
}
lzma_index_stream_flags(lzma_index *i, const lzma_stream_flags *stream_flags)
{
if (i == NULL || stream_flags == NULL)
return LZMA_PROG_ERROR;
// Validate the Stream Flags.
return_if_error(lzma_stream_flags_compare(
stream_flags, stream_flags));
index_stream *s = (index_stream *)(i->streams.rightmost);
s->stream_flags = *stream_flags;
return LZMA_OK;
}
value value_cons_now2(value *op1, value *op2)
{
if (op2->type == VALUE_NIL) {
op2->type = VALUE_PAR;
value_malloc(op2, 2);
if (op2->type == VALUE_ERROR) return;
op2->core.u_p->head = *op1;
op2->core.u_p->tail = value_init_nil();
} else if (op2->type == VALUE_ARY) {
value res;
res.type = VALUE_ARY;
size_t i, length = value_length(*op2);
if (resize_p(length+1)) {
value_realloc(op1, next_size(length+1) + 1);
if (op1->type == VALUE_ERROR)
return value_init_error();
}
for (i = 1; i < length; ++i)
res.core.u_a.a[i+1] = op2->core.u_a.a[i];
res.core.u_a.a[0] = *op1;
res.core.u_a.length = op2->core.u_a.length + 1;
*op2 = res;
} else if (op2->type == VALUE_LST) {
value res;
res.type = VALUE_LST;
value_malloc(&res, 2);
if (res.type == VALUE_ERROR) {
return value_init_error();
}
res.core.u_l[0] = *op1;
res.core.u_l[1] = *op2;
*op2 = res;
} else if (op2->type == VALUE_PAR) {
value res;
res.type = VALUE_PAR;
value_malloc(&res, 2);
return_if_error(res);
res.core.u_l[0] = *op1;
res.core.u_l[1] = *op2;
*op2 = res;
} else {
value_error(1, "Type Error: cons() is undefined where op2 is %ts (nil, array or list expected).", *op2);
return value_init_error();
}
return value_init_nil();
}
static lzma_ret
block_encoder_init(lzma_coder *coder, const lzma_allocator *allocator)
{
// Prepare the Block options. Even though Block encoder doesn't need
// compressed_size, uncompressed_size, and header_size to be
// initialized, it is a good idea to do it here, because this way
// we catch if someone gave us Filter ID that cannot be used in
// Blocks/Streams.
coder->block_options.compressed_size = LZMA_VLI_UNKNOWN;
coder->block_options.uncompressed_size = LZMA_VLI_UNKNOWN;
return_if_error(lzma_block_header_size(&coder->block_options));
// Initialize the actual Block encoder.
return lzma_block_encoder_init(&coder->block_encoder, allocator,
&coder->block_options);
}
extern lzma_ret
lzma_outq_init(lzma_outq *outq, const lzma_allocator *allocator,
uint64_t buf_size_max, uint32_t threads)
{
uint64_t bufs_alloc_size;
uint32_t bufs_count;
// Set bufs_count and bufs_alloc_size.
return_if_error(get_options(&bufs_alloc_size, &bufs_count,
buf_size_max, threads));
// Allocate memory if needed.
if (outq->buf_size_max != buf_size_max
|| outq->bufs_allocated != bufs_count) {
lzma_outq_end(outq, allocator);
#if SIZE_MAX < UINT64_MAX
if (bufs_alloc_size > SIZE_MAX)
return LZMA_MEM_ERROR;
#endif
outq->bufs = lzma_alloc(bufs_count * sizeof(lzma_outbuf),
allocator);
outq->bufs_mem = lzma_alloc((size_t)(bufs_alloc_size),
allocator);
if (outq->bufs == NULL || outq->bufs_mem == NULL) {
lzma_outq_end(outq, allocator);
return LZMA_MEM_ERROR;
}
}
// Initialize the rest of the main structure. Initialization of
// outq->bufs[] is done when they are actually needed.
outq->buf_size_max = (size_t)(buf_size_max);
outq->bufs_allocated = bufs_count;
outq->bufs_pos = 0;
outq->bufs_used = 0;
outq->read_pos = 0;
return LZMA_OK;
}
lzma_raw_buffer_encode(const lzma_filter *filters, lzma_allocator *allocator,
const uint8_t *in, size_t in_size, uint8_t *out,
size_t *out_pos, size_t out_size)
{
// Validate what isn't validated later in filter_common.c.
if ((in == NULL && in_size != 0) || out == NULL
|| out_pos == NULL || *out_pos > out_size)
return LZMA_PROG_ERROR;
// Initialize the encoder
lzma_next_coder next = LZMA_NEXT_CODER_INIT;
return_if_error(lzma_raw_encoder_init(&next, allocator, filters));
// Store the output position so that we can restore it if
// something goes wrong.
const size_t out_start = *out_pos;
// Do the actual encoding and free coder's memory.
size_t in_pos = 0;
lzma_ret ret = next.code(next.coder, allocator, in, &in_pos, in_size,
out, out_pos, out_size, LZMA_FINISH);
lzma_next_end(&next, allocator);
if (ret == LZMA_STREAM_END) {
ret = LZMA_OK;
} else {
if (ret == LZMA_OK) {
// Output buffer was too small.
assert(*out_pos == out_size);
ret = LZMA_BUF_ERROR;
}
// Restore the output position.
*out_pos = out_start;
}
return ret;
}
static lzma_ret
stream_encoder_update(lzma_coder *coder, const lzma_allocator *allocator,
const lzma_filter *filters,
const lzma_filter *reversed_filters)
{
if (coder->sequence <= SEQ_BLOCK_INIT) {
// There is no incomplete Block waiting to be finished,
// thus we can change the whole filter chain. Start by
// trying to initialize the Block encoder with the new
// chain. This way we detect if the chain is valid.
coder->block_encoder_is_initialized = false;
coder->block_options.filters = (lzma_filter *)(filters);
const lzma_ret ret = block_encoder_init(coder, allocator);
coder->block_options.filters = coder->filters;
if (ret != LZMA_OK)
return ret;
coder->block_encoder_is_initialized = true;
} else if (coder->sequence <= SEQ_BLOCK_ENCODE) {
// We are in the middle of a Block. Try to update only
// the filter-specific options.
return_if_error(coder->block_encoder.update(
coder->block_encoder.coder, allocator,
filters, reversed_filters));
} else {
// Trying to update the filter chain when we are already
// encoding Index or Stream Footer.
return LZMA_PROG_ERROR;
}
// Free the copy of the old chain and make a copy of the new chain.
for (size_t i = 0; coder->filters[i].id != LZMA_VLI_UNKNOWN; ++i)
lzma_free(coder->filters[i].options, allocator);
return lzma_filters_copy(filters, coder->filters, allocator);
}
lzma_raw_buffer_decode(const lzma_filter *filters, lzma_allocator *allocator,
const uint8_t *in, size_t *in_pos, size_t in_size,
uint8_t *out, size_t *out_pos, size_t out_size)
{
// Validate what isn't validated later in filter_common.c.
if (in == NULL || in_pos == NULL || *in_pos > in_size || out == NULL
|| out_pos == NULL || *out_pos > out_size)
return LZMA_PROG_ERROR;
// Initialize the decoer.
lzma_next_coder next = LZMA_NEXT_CODER_INIT;
return_if_error(lzma_raw_decoder_init(&next, allocator, filters));
// Store the positions so that we can restore them if something
// goes wrong.
const size_t in_start = *in_pos;
const size_t out_start = *out_pos;
// Do the actual decoding and free decoder's memory.
lzma_ret ret = next.code(next.coder, allocator, in, in_pos, in_size,
out, out_pos, out_size, LZMA_FINISH);
if (ret == LZMA_STREAM_END) {
ret = LZMA_OK;
} else {
if (ret == LZMA_OK) {
// Either the input was truncated or the
// output buffer was too small.
assert(*in_pos == in_size || *out_pos == out_size);
if (*in_pos != in_size) {
// Since input wasn't consumed completely,
// the output buffer became full and is
// too small.
ret = LZMA_BUF_ERROR;
} else if (*out_pos != out_size) {
// Since output didn't became full, the input
// has to be truncated.
ret = LZMA_DATA_ERROR;
} else {
// All the input was consumed and output
// buffer is full. Now we don't immediately
// know the reason for the error. Try
// decoding one more byte. If it succeeds,
// then the output buffer was too small. If
// we cannot get a new output byte, the input
// is truncated.
uint8_t tmp[1];
size_t tmp_pos = 0;
(void)next.code(next.coder, allocator,
in, in_pos, in_size,
tmp, &tmp_pos, 1, LZMA_FINISH);
if (tmp_pos == 1)
ret = LZMA_BUF_ERROR;
else
ret = LZMA_DATA_ERROR;
}
}
// Restore the positions.
*in_pos = in_start;
*out_pos = out_start;
}
lzma_next_end(&next, allocator);
return ret;
}
lzma_block_header_decode(lzma_block *block,
lzma_allocator *allocator, const uint8_t *in)
{
const size_t filter_count = (in[1] & 3) + 1;
size_t in_size;
size_t i;
// Start after the Block Header Size and Block Flags fields.
size_t in_pos = 2;
// NOTE: We consider the header to be corrupt not only when the
// CRC32 doesn't match, but also when variable-length integers
// are invalid or over 63 bits, or if the header is too small
// to contain the claimed information.
// Initialize the filter options array. This way the caller can
// safely free() the options even if an error occurs in this function.
for (i = 0; i <= LZMA_FILTERS_MAX; ++i) {
block->filters[i].id = LZMA_VLI_UNKNOWN;
block->filters[i].options = NULL;
}
// Always zero for now.
block->version = 0;
// Validate Block Header Size and Check type. The caller must have
// already set these, so it is a programming error if this test fails.
if (lzma_block_header_size_decode(in[0]) != block->header_size
|| (unsigned int)(block->check) > LZMA_CHECK_ID_MAX)
return LZMA_PROG_ERROR;
// Exclude the CRC32 field.
in_size = block->header_size - 4;
// Verify CRC32
if (lzma_crc32(in, in_size, 0) != unaligned_read32le(in + in_size))
return LZMA_DATA_ERROR;
// Check for unsupported flags.
if (in[1] & 0x3C)
return LZMA_OPTIONS_ERROR;
// Compressed Size
if (in[1] & 0x40) {
return_if_error(lzma_vli_decode(&block->compressed_size,
NULL, in, &in_pos, in_size));
// Validate Compressed Size. This checks that it isn't zero
// and that the total size of the Block is a valid VLI.
if (lzma_block_unpadded_size(block) == 0)
return LZMA_DATA_ERROR;
} else {
block->compressed_size = LZMA_VLI_UNKNOWN;
}
// Uncompressed Size
if (in[1] & 0x80)
return_if_error(lzma_vli_decode(&block->uncompressed_size,
NULL, in, &in_pos, in_size));
else
block->uncompressed_size = LZMA_VLI_UNKNOWN;
// Filter Flags
for (i = 0; i < filter_count; ++i) {
const lzma_ret ret = lzma_filter_flags_decode(
&block->filters[i], allocator,
in, &in_pos, in_size);
if (ret != LZMA_OK) {
free_properties(block, allocator);
return ret;
}
}
// Padding
while (in_pos < in_size) {
if (in[in_pos++] != 0x00) {
free_properties(block, allocator);
// Possibly some new field present so use
// LZMA_OPTIONS_ERROR instead of LZMA_DATA_ERROR.
return LZMA_OPTIONS_ERROR;
}
}
return LZMA_OK;
}
static lzma_ret
stream_encoder_init(lzma_next_coder *next, const lzma_allocator *allocator,
const lzma_filter *filters, lzma_check check)
{
lzma_next_coder_init(&stream_encoder_init, next, allocator);
if (filters == NULL)
return LZMA_PROG_ERROR;
if (next->coder == NULL) {
next->coder = lzma_alloc(sizeof(lzma_coder), allocator);
if (next->coder == NULL)
return LZMA_MEM_ERROR;
next->code = &stream_encode;
next->end = &stream_encoder_end;
next->update = &stream_encoder_update;
next->coder->filters[0].id = LZMA_VLI_UNKNOWN;
next->coder->block_encoder = LZMA_NEXT_CODER_INIT;
next->coder->index_encoder = LZMA_NEXT_CODER_INIT;
next->coder->index = NULL;
}
// Basic initializations
next->coder->sequence = SEQ_STREAM_HEADER;
next->coder->block_options.version = 0;
next->coder->block_options.check = check;
// Initialize the Index
lzma_index_end(next->coder->index, allocator);
next->coder->index = lzma_index_init(allocator);
if (next->coder->index == NULL)
return LZMA_MEM_ERROR;
// Encode the Stream Header
lzma_stream_flags stream_flags = {
.version = 0,
.check = check,
};
return_if_error(lzma_stream_header_encode(
&stream_flags, next->coder->buffer));
next->coder->buffer_pos = 0;
next->coder->buffer_size = LZMA_STREAM_HEADER_SIZE;
// Initialize the Block encoder. This way we detect unsupported
// filter chains when initializing the Stream encoder instead of
// giving an error after Stream Header has already written out.
return stream_encoder_update(
next->coder, allocator, filters, NULL);
}
extern LZMA_API(lzma_ret)
lzma_stream_encoder(lzma_stream *strm,
const lzma_filter *filters, lzma_check check)
{
lzma_next_strm_init(stream_encoder_init, strm, filters, check);
strm->internal->supported_actions[LZMA_RUN] = true;
strm->internal->supported_actions[LZMA_SYNC_FLUSH] = true;
strm->internal->supported_actions[LZMA_FULL_FLUSH] = true;
strm->internal->supported_actions[LZMA_FINISH] = true;
return LZMA_OK;
}
lzma_block_buffer_encode(lzma_block *block, lzma_allocator *allocator,
const uint8_t *in, size_t in_size,
uint8_t *out, size_t *out_pos, size_t out_size)
{
size_t check_size;
lzma_ret ret;
size_t i;
// Validate the arguments.
if (block == NULL || (in == NULL && in_size != 0) || out == NULL
|| out_pos == NULL || *out_pos > out_size)
return LZMA_PROG_ERROR;
// The contents of the structure may depend on the version so
// check the version before validating the contents of *block.
if (block->version != 0)
return LZMA_OPTIONS_ERROR;
if ((unsigned int)(block->check) > LZMA_CHECK_ID_MAX
|| block->filters == NULL)
return LZMA_PROG_ERROR;
if (!lzma_check_is_supported(block->check))
return LZMA_UNSUPPORTED_CHECK;
// Size of a Block has to be a multiple of four, so limit the size
// here already. This way we don't need to check it again when adding
// Block Padding.
out_size -= (out_size - *out_pos) & 3;
// Get the size of the Check field.
check_size = lzma_check_size(block->check);
assert(check_size != UINT32_MAX);
// Reserve space for the Check field.
if (out_size - *out_pos <= check_size)
return LZMA_BUF_ERROR;
out_size -= check_size;
// Do the actual compression.
ret = block_encode_normal(block, allocator,
in, in_size, out, out_pos, out_size);
if (ret != LZMA_OK) {
// If the error was something else than output buffer
// becoming full, return the error now.
if (ret != LZMA_BUF_ERROR)
return ret;
// The data was uncompressible (at least with the options
// given to us) or the output buffer was too small. Use the
// uncompressed chunks of LZMA2 to wrap the data into a valid
// Block. If we haven't been given enough output space, even
// this may fail.
return_if_error(block_encode_uncompressed(block, in, in_size,
out, out_pos, out_size));
}
assert(*out_pos <= out_size);
// Block Padding. No buffer overflow here, because we already adjusted
// out_size so that (out_size - out_start) is a multiple of four.
// Thus, if the buffer is full, the loop body can never run.
for (i = (size_t)(block->compressed_size); i & 3; ++i) {
assert(*out_pos < out_size);
out[(*out_pos)++] = 0x00;
}
// If there's no Check field, we are done now.
if (check_size > 0) {
// Calculate the integrity check. We reserved space for
// the Check field earlier so we don't need to check for
// available output space here.
lzma_check_state check;
lzma_check_init(&check, block->check);
lzma_check_update(&check, block->check, in, in_size);
lzma_check_finish(&check, block->check);
memcpy(block->raw_check, check.buffer.u8, check_size);
memcpy(out + *out_pos, check.buffer.u8, check_size);
*out_pos += check_size;
}
return LZMA_OK;
}
static lzma_ret
block_encode_normal(lzma_block *block, lzma_allocator *allocator,
const uint8_t *in, size_t in_size,
uint8_t *out, size_t *out_pos, size_t out_size)
{
size_t out_start;
lzma_next_coder raw_encoder = LZMA_NEXT_CODER_INIT;
lzma_ret ret;
// Find out the size of the Block Header.
block->compressed_size = lzma2_bound(in_size);
if (block->compressed_size == 0)
return LZMA_DATA_ERROR;
block->uncompressed_size = in_size;
return_if_error(lzma_block_header_size(block));
// Reserve space for the Block Header and skip it for now.
if (out_size - *out_pos <= block->header_size)
return LZMA_BUF_ERROR;
out_start = *out_pos;
*out_pos += block->header_size;
// Limit out_size so that we stop encoding if the output would grow
// bigger than what uncompressed Block would be.
if (out_size - *out_pos > block->compressed_size)
out_size = *out_pos + block->compressed_size;
// TODO: In many common cases this could be optimized to use
// significantly less memory.
ret = lzma_raw_encoder_init(
&raw_encoder, allocator, block->filters);
if (ret == LZMA_OK) {
size_t in_pos = 0;
ret = raw_encoder.code(raw_encoder.coder, allocator,
in, &in_pos, in_size, out, out_pos, out_size,
LZMA_FINISH);
}
// NOTE: This needs to be run even if lzma_raw_encoder_init() failed.
lzma_next_end(&raw_encoder, allocator);
if (ret == LZMA_STREAM_END) {
// Compression was successful. Write the Block Header.
block->compressed_size
= *out_pos - (out_start + block->header_size);
ret = lzma_block_header_encode(block, out + out_start);
if (ret != LZMA_OK)
ret = LZMA_PROG_ERROR;
} else if (ret == LZMA_OK) {
// Output buffer became full.
ret = LZMA_BUF_ERROR;
}
// Reset *out_pos if something went wrong.
if (ret != LZMA_OK)
*out_pos = out_start;
return ret;
}
lzma_stream_buffer_encode(lzma_filter *filters, lzma_check check,
lzma_allocator *allocator, const uint8_t *in, size_t in_size,
uint8_t *out, size_t *out_pos_ptr, size_t out_size)
{
// Sanity checks
if (filters == NULL || (unsigned int)(check) > LZMA_CHECK_ID_MAX
|| (in == NULL && in_size != 0) || out == NULL
|| out_pos_ptr == NULL || *out_pos_ptr > out_size)
return LZMA_PROG_ERROR;
if (!lzma_check_is_supported(check))
return LZMA_UNSUPPORTED_CHECK;
// Note for the paranoids: Index encoder prevents the Stream from
// getting too big and still being accepted with LZMA_OK, and Block
// encoder catches if the input is too big. So we don't need to
// separately check if the buffers are too big.
// Use a local copy. We update *out_pos_ptr only if everything
// succeeds.
size_t out_pos = *out_pos_ptr;
// Check that there's enough space for both Stream Header and
// Stream Footer.
if (out_size - out_pos <= 2 * LZMA_STREAM_HEADER_SIZE)
return LZMA_BUF_ERROR;
// Reserve space for Stream Footer so we don't need to check for
// available space again before encoding Stream Footer.
out_size -= LZMA_STREAM_HEADER_SIZE;
// Encode the Stream Header.
lzma_stream_flags stream_flags = {
.version = 0,
.check = check,
};
if (lzma_stream_header_encode(&stream_flags, out + out_pos)
!= LZMA_OK)
return LZMA_PROG_ERROR;
out_pos += LZMA_STREAM_HEADER_SIZE;
// Encode a Block but only if there is at least one byte of input.
lzma_block block = {
.version = 0,
.check = check,
.filters = filters,
};
if (in_size > 0)
return_if_error(lzma_block_buffer_encode(&block, allocator,
in, in_size, out, &out_pos, out_size));
// Index
{
// Create an Index. It will have one Record if there was
// at least one byte of input to encode. Otherwise the
// Index will be empty.
lzma_index *i = lzma_index_init(allocator);
if (i == NULL)
return LZMA_MEM_ERROR;
lzma_ret ret = LZMA_OK;
if (in_size > 0)
ret = lzma_index_append(i, allocator,
lzma_block_unpadded_size(&block),
block.uncompressed_size);
// If adding the Record was successful, encode the Index
// and get its size which will be stored into Stream Footer.
if (ret == LZMA_OK) {
ret = lzma_index_buffer_encode(
i, out, &out_pos, out_size);
stream_flags.backward_size = lzma_index_size(i);
}
lzma_index_end(i, allocator);
if (ret != LZMA_OK)
return ret;
}
// Stream Footer. We have already reserved space for this.
if (lzma_stream_footer_encode(&stream_flags, out + out_pos)
!= LZMA_OK)
return LZMA_PROG_ERROR;
out_pos += LZMA_STREAM_HEADER_SIZE;
// Everything went fine, make the new output position available
// to the application.
*out_pos_ptr = out_pos;
return LZMA_OK;
}
