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;
}
lzma_index_append(lzma_index *i, lzma_allocator *allocator,
lzma_vli unpadded_size, lzma_vli uncompressed_size)
{
if (unpadded_size < UNPADDED_SIZE_MIN
|| unpadded_size > UNPADDED_SIZE_MAX
|| uncompressed_size > LZMA_VLI_MAX)
return LZMA_PROG_ERROR;
// This looks a bit ugly. We want to first validate that the Index
// and Stream stay in valid limits after adding this Record. After
// validating, we may need to allocate a new lzma_index_group (it's
// slightly more correct to validate before allocating, YMMV).
lzma_ret ret;
// First update the overall info so we can validate it.
const lzma_vli index_list_size_add = lzma_vli_size(unpadded_size)
+ lzma_vli_size(uncompressed_size);
const lzma_vli total_size = vli_ceil4(unpadded_size);
i->total_size += total_size;
i->uncompressed_size += uncompressed_size;
++i->count;
i->index_list_size += index_list_size_add;
if (i->total_size > LZMA_VLI_MAX
|| i->uncompressed_size > LZMA_VLI_MAX
|| lzma_index_size(i) > LZMA_BACKWARD_SIZE_MAX
|| lzma_index_file_size(i) > LZMA_VLI_MAX)
ret = LZMA_DATA_ERROR; // Would grow past the limits.
else
ret = index_append_real(i, allocator, unpadded_size,
uncompressed_size, false);
if (ret != LZMA_OK) {
// Something went wrong. Undo the updates.
i->total_size -= total_size;
i->uncompressed_size -= uncompressed_size;
--i->count;
i->index_list_size -= index_list_size_add;
}
return ret;
}
lzma_index_append(lzma_index *i, const lzma_allocator *allocator,
lzma_vli unpadded_size, lzma_vli uncompressed_size)
{
// Validate.
if (i == NULL || unpadded_size < UNPADDED_SIZE_MIN
|| unpadded_size > UNPADDED_SIZE_MAX
|| uncompressed_size > LZMA_VLI_MAX)
return LZMA_PROG_ERROR;
index_stream *s = (index_stream *)(i->streams.rightmost);
index_group *g = (index_group *)(s->groups.rightmost);
const lzma_vli compressed_base = g == NULL ? 0
: vli_ceil4(g->records[g->last].unpadded_sum);
const lzma_vli uncompressed_base = g == NULL ? 0
: g->records[g->last].uncompressed_sum;
const uint32_t index_list_size_add = lzma_vli_size(unpadded_size)
+ lzma_vli_size(uncompressed_size);
// Check that the file size will stay within limits.
if (index_file_size(s->node.compressed_base,
compressed_base + unpadded_size, s->record_count + 1,
s->index_list_size + index_list_size_add,
s->stream_padding) == LZMA_VLI_UNKNOWN)
return LZMA_DATA_ERROR;
// The size of the Index field must not exceed the maximum value
// that can be stored in the Backward Size field.
if (index_size(i->record_count + 1,
i->index_list_size + index_list_size_add)
> LZMA_BACKWARD_SIZE_MAX)
return LZMA_DATA_ERROR;
if (g != NULL && g->last + 1 < g->allocated) {
// There is space in the last group at least for one Record.
++g->last;
} else {
// We need to allocate a new group.
g = lzma_alloc(sizeof(index_group)
+ i->prealloc * sizeof(index_record),
allocator);
if (g == NULL)
return LZMA_MEM_ERROR;
g->last = 0;
g->allocated = i->prealloc;
// Reset prealloc so that if the application happens to
// add new Records, the allocation size will be sane.
i->prealloc = INDEX_GROUP_SIZE;
// Set the start offsets of this group.
g->node.uncompressed_base = uncompressed_base;
g->node.compressed_base = compressed_base;
g->number_base = s->record_count + 1;
// Add the new group to the Stream.
index_tree_append(&s->groups, &g->node);
}
// Add the new Record to the group.
g->records[g->last].uncompressed_sum
= uncompressed_base + uncompressed_size;
g->records[g->last].unpadded_sum
= compressed_base + unpadded_size;
// Update the totals.
++s->record_count;
s->index_list_size += index_list_size_add;
i->total_size += vli_ceil4(unpadded_size);
i->uncompressed_size += uncompressed_size;
++i->record_count;
i->index_list_size += index_list_size_add;
return LZMA_OK;
}
