mirror of https://git.tukaani.org/xz.git
Add some single-call buffer-to-buffer coding functions.
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@ -55,6 +55,7 @@ typedef struct {
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* - lzma_block_total_size()
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* - lzma_block_encoder()
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* - lzma_block_decoder()
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* - lzma_block_buffer_encode()
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*
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* Written by:
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* - lzma_block_header_decode()
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@ -76,6 +77,7 @@ typedef struct {
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*
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* Written by:
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* - lzma_block_header_size()
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* - lzma_block_buffer_encode()
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*/
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uint32_t header_size;
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# define LZMA_BLOCK_HEADER_SIZE_MIN 8
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@ -95,6 +97,7 @@ typedef struct {
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* - lzma_block_total_size()
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* - lzma_block_encoder()
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* - lzma_block_decoder()
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* - lzma_block_buffer_encode()
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*/
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lzma_check check;
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@ -147,6 +150,7 @@ typedef struct {
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* - lzma_block_compressed_size()
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* - lzma_block_encoder()
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* - lzma_block_decoder()
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* - lzma_block_buffer_encode()
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*/
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lzma_vli compressed_size;
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@ -168,6 +172,7 @@ typedef struct {
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* - lzma_block_header_decode()
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* - lzma_block_encoder()
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* - lzma_block_decoder()
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* - lzma_block_buffer_encode()
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*/
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lzma_vli uncompressed_size;
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@ -182,6 +187,7 @@ typedef struct {
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* - lzma_block_header_encode()
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* - lzma_block_encoder()
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* - lzma_block_decoder()
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* - lzma_block_buffer_encode()
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*
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* Written by:
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* - lzma_block_header_decode(): Note that this does NOT free()
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@ -415,3 +421,54 @@ extern lzma_ret lzma_block_encoder(lzma_stream *strm, lzma_block *block)
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*/
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extern lzma_ret lzma_block_decoder(lzma_stream *strm, lzma_block *block)
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lzma_attr_warn_unused_result;
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/**
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* \brief Calculate maximum output buffer size for single-call encoding
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*
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* This is equivalent to lzma_stream_buffer_bound() but for .xz Blocks.
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* See the documentation of lzma_stream_buffer_bound().
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*/
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extern size_t lzma_block_buffer_bound(size_t uncompressed_size);
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/**
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* \brief Single-call .xz Block encoder
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*
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* In contrast to the multi-call encoder initialized with
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* lzma_block_encoder(), this function encodes also the Block Header. This
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* is required to make it possible to write appropriate Block Header also
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* in case the data isn't compressible, and different filter chain has to be
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* used to encode the data in uncompressed form using uncompressed chunks
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* of the LZMA2 filter.
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*
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* When the data isn't compressible, header_size, compressed_size, and
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* uncompressed_size are set just like when the data was compressible, but
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* it is possible that header_size is too small to hold the filter chain
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* specified in block->filters, because that isn't necessarily the filter
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* chain that was actually used to encode the data. lzma_block_unpadded_size()
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* still works normally, because it doesn't read the filters array.
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*
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* \param block Block options: block->version, block->check,
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* and block->filters must be initialized.
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* \param allocator lzma_allocator for custom allocator functions.
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* Set to NULL to use malloc() and free().
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* \param in Beginning of the input buffer
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* \param in_size Size of the input buffer
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* \param out Beginning of the output buffer
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* \param out_pos The next byte will be written to out[*out_pos].
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* *out_pos is updated only if encoding succeeds.
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* \param out_size Size of the out buffer; the first byte into
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* which no data is written to is out[out_size].
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*
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* \return - LZMA_OK: Encoding was successful.
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* - LZMA_BUF_ERROR: Not enough output buffer space.
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* - LZMA_OPTIONS_ERROR
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* - LZMA_MEM_ERROR
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* - LZMA_DATA_ERROR
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* - LZMA_PROG_ERROR
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*/
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extern lzma_ret lzma_block_buffer_encode(
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lzma_block *block, lzma_allocator *allocator,
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const uint8_t *in, size_t in_size,
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uint8_t *out, size_t *out_pos, size_t out_size);
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@ -169,6 +169,62 @@ extern lzma_ret lzma_alone_encoder(
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lzma_attr_warn_unused_result;
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/**
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* \brief Calculate output buffer size for single-call Stream encoder
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*
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* When trying to compress uncompressible data, the encoded size will be
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* slightly bigger than the input data. This function calculates how much
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* output buffer space is required to be sure that lzma_stream_buffer_encode()
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* doesn't return LZMA_BUF_ERROR.
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*
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* The calculated value is not exact, but it is guaranteed to be big enough.
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* The actual maximum output space required may be slightly smaller (up to
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* about 100 bytes). This should not be a problem in practice.
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*
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* If the calculated maximum size doesn't fit into size_t or would make the
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* Stream grow past LZMA_VLI_MAX (which should never happen in practice),
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* zero is returned to indicate the error.
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*
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* \note The limit calculated by this function applies only to
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* single-call encoding. Multi-call encoding may (and probably
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* will) have larger maximum expansion when encoding
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* uncompressible data. Currently there is no function to
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* calculate the maximum expansion of multi-call encoding.
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*/
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extern size_t lzma_stream_buffer_bound(size_t uncompressed_size);
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/**
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* \brief Single-call Stream encoder
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*
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* \param filters Array of filters. This must be terminated with
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* filters[n].id = LZMA_VLI_UNKNOWN. See filter.h
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* for more information.
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* \param check Type of the integrity check to calculate from
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* uncompressed data.
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* \param allocator lzma_allocator for custom allocator functions.
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* Set to NULL to use malloc() and free().
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* \param in Beginning of the input buffer
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* \param in_size Size of the input buffer
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* \param out Beginning of the output buffer
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* \param out_pos The next byte will be written to out[*out_pos].
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* *out_pos is updated only if encoding succeeds.
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* \param out_size Size of the out buffer; the first byte into
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* which no data is written to is out[out_size].
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*
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* \return - LZMA_OK: Encoding was successful.
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* - LZMA_BUF_ERROR: Not enough output buffer space.
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* - LZMA_OPTIONS_ERROR
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* - LZMA_MEM_ERROR
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* - LZMA_DATA_ERROR
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* - LZMA_PROG_ERROR
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*/
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extern lzma_ret lzma_stream_buffer_encode(
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lzma_filter *filters, lzma_check check,
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lzma_allocator *allocator, const uint8_t *in, size_t in_size,
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uint8_t *out, size_t *out_pos, size_t out_size);
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/************
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* Decoding *
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************/
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@ -255,7 +255,7 @@ extern lzma_ret lzma_index_cat(lzma_index *lzma_restrict dest,
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/**
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* \brief Duplicates an Index list
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* \brief Duplicate an Index list
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*
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* Makes an identical copy of the Index. Also the read position is copied.
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*
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@ -267,7 +267,7 @@ extern lzma_index *lzma_index_dup(
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/**
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* \brief Compares if two Index lists are identical
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* \brief Compare if two Index lists are identical
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*
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* \return True if *a and *b are equal, false otherwise.
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*/
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@ -276,7 +276,7 @@ extern lzma_bool lzma_index_equal(const lzma_index *a, const lzma_index *b)
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/**
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* \brief Initializes Index encoder
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* \brief Initialize Index encoder
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*
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* \param strm Pointer to properly prepared lzma_stream
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* \param i Pointer to lzma_index which should be encoded.
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@ -294,14 +294,15 @@ extern lzma_ret lzma_index_encoder(lzma_stream *strm, lzma_index *i)
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/**
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* \brief Initializes Index decoder
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* \brief Initialize Index decoder
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*
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* \param strm Pointer to properly prepared lzma_stream
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* \param i Pointer to a pointer that will be made to point
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* to the final decoded Index once lzma_code() has
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* returned LZMA_STREAM_END. That is,
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* lzma_index_decoder() takes care of allocating
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* a new lzma_index structure.
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* lzma_index_decoder() always takes care of
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* allocating a new lzma_index structure, and *i
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* doesn't need to be initialized by the caller.
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* \param memlimit How much memory the resulting Index is allowed
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* to require.
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*
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@ -321,3 +322,60 @@ extern lzma_ret lzma_index_encoder(lzma_stream *strm, lzma_index *i)
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extern lzma_ret lzma_index_decoder(
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lzma_stream *strm, lzma_index **i, uint64_t memlimit)
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lzma_attr_warn_unused_result;
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/**
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* \brief Single-call Index encoder
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*
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* \param i Index to be encoded. The read position will be at
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* the end of the Index if encoding succeeds, or at
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* unspecified position in case an error occurs.
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* \param out Beginning of the output buffer
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* \param out_pos The next byte will be written to out[*out_pos].
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* *out_pos is updated only if encoding succeeds.
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* \param out_size Size of the out buffer; the first byte into
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* which no data is written to is out[out_size].
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*
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* \return - LZMA_OK: Encoding was successful.
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* - LZMA_BUF_ERROR: Output buffer is too small. Use
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* lzma_index_size() to find out how much output
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* space is needed.
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* - LZMA_PROG_ERROR
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*
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* \note This function doesn't take allocator argument since all
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* the internal data is allocated on stack.
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*/
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extern lzma_ret lzma_index_buffer_encode(lzma_index *i,
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uint8_t *out, size_t *out_pos, size_t out_size);
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/**
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* \brief Single-call Index decoder
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*
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* \param i Pointer to a pointer that will be made to point
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* to the final decoded Index if decoding is
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* successful. That is, lzma_index_buffer_decode()
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* always takes care of allocating a new
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* lzma_index structure, and *i doesn't need to be
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* initialized by the caller.
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* \param memlimit Pointer to how much memory the resulting Index
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* is allowed to require. The value pointed by
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* this pointer is modified if and only if
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* LZMA_MEMLIMIT_ERROR is returned.
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* \param allocator Pointer to lzma_allocator, or NULL to use malloc()
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* \param in Beginning of the input buffer
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* \param in_pos The next byte will be read from in[*in_pos].
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* *in_pos is updated only if decoding succeeds.
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* \param in_size Size of the input buffer; the first byte that
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* won't be read is in[in_size].
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*
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* \return - LZMA_OK: Decoding was successful.
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* - LZMA_MEM_ERROR
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* - LZMA_MEMLIMIT_ERROR: Memory usage limit was reached.
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* The minimum required memlimit value was stored to *memlimit.
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* - LZMA_DATA_ERROR
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* - LZMA_PROG_ERROR
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*/
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extern lzma_ret lzma_index_buffer_decode(
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lzma_index **i, uint64_t *memlimit, lzma_allocator *allocator,
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const uint8_t *in, size_t *in_pos, size_t in_size);
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@ -39,6 +39,7 @@ libcommon_la_SOURCES = \
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if COND_MAIN_ENCODER
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libcommon_la_SOURCES += \
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alone_encoder.c \
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block_buffer_encoder.c \
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block_encoder.c \
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block_encoder.h \
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block_header_encoder.c \
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@ -48,6 +49,7 @@ libcommon_la_SOURCES += \
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filter_flags_encoder.c \
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index_encoder.c \
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index_encoder.h \
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stream_buffer_encoder.c \
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stream_encoder.c \
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stream_encoder.h \
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stream_flags_encoder.c \
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@ -0,0 +1,305 @@
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///////////////////////////////////////////////////////////////////////////////
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//
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/// \file block_buffer_encoder.c
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/// \brief Single-call .xz Block encoder
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//
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// Copyright (C) 2009 Lasse Collin
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//
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// This library is free software; you can redistribute it and/or
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// modify it under the terms of the GNU Lesser General Public
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// License as published by the Free Software Foundation; either
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// version 2.1 of the License, or (at your option) any later version.
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//
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// This library is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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// Lesser General Public License for more details.
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//
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///////////////////////////////////////////////////////////////////////////////
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#include "block_encoder.h"
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#include "filter_encoder.h"
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#include "lzma2_encoder.h"
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#include "check.h"
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/// Estimate the maximum size of the Block Header and Check fields for
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/// a Block that uses LZMA2 uncompressed chunks. We could use
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/// lzma_block_header_size() but this is simpler.
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///
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/// Block Header Size + Block Flags + Compressed Size
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/// + Uncompressed Size + Filter Flags for LZMA2 + CRC32 + Check
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/// and round up to the next multiple of four to take Header Padding
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/// into account.
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#define HEADERS_BOUND ((1 + 1 + 2 * LZMA_VLI_BYTES_MAX + 3 + 4 \
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+ LZMA_CHECK_SIZE_MAX + 3) & ~3)
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static lzma_vli
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lzma2_bound(lzma_vli uncompressed_size)
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{
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// Prevent integer overflow in overhead calculation.
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if (uncompressed_size > COMPRESSED_SIZE_MAX)
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return 0;
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// Calculate the exact overhead of the LZMA2 headers: Round
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// uncompressed_size up to the next multiple of LZMA2_CHUNK_MAX,
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// multiply by the size of per-chunk header, and add one byte for
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// the end marker.
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const lzma_vli overhead = ((uncompressed_size + LZMA2_CHUNK_MAX - 1)
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/ LZMA2_CHUNK_MAX)
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* LZMA2_HEADER_UNCOMPRESSED + 1;
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// Catch the possible integer overflow.
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if (COMPRESSED_SIZE_MAX - overhead < uncompressed_size)
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return 0;
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return uncompressed_size + overhead;
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}
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extern LZMA_API size_t
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lzma_block_buffer_bound(size_t uncompressed_size)
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{
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// For now, if the data doesn't compress, we always use uncompressed
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// chunks of LZMA2. In future we may use Subblock filter too, but
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// but for simplicity we probably will still use the same bound
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// calculation even though Subblock filter would have slightly less
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// overhead.
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lzma_vli lzma2_size = lzma2_bound(uncompressed_size);
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if (lzma2_size == 0)
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return 0;
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// Take Block Padding into account.
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lzma2_size = (lzma2_size + 3) & ~LZMA_VLI_C(3);
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#if SIZE_MAX < LZMA_VLI_MAX
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// Catch the possible integer overflow on 32-bit systems. There's no
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// overflow on 64-bit systems, because lzma2_bound() already takes
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// into account the size of the headers in the Block.
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if (SIZE_MAX - HEADERS_BOUND < lzma2_size)
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return 0;
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#endif
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return HEADERS_BOUND + lzma2_size;
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}
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static lzma_ret
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block_encode_uncompressed(lzma_block *block, const uint8_t *in, size_t in_size,
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uint8_t *out, size_t *out_pos, size_t out_size)
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{
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// TODO: Figure out if the last filter is LZMA2 or Subblock and use
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// that filter to encode the uncompressed chunks.
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// Use LZMA2 uncompressed chunks. We wouldn't need a dictionary at
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// all, but LZMA2 always requires a dictionary, so use the minimum
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// value to minimize memory usage of the decoder.
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lzma_options_lzma lzma2 = {
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.dict_size = LZMA_DICT_SIZE_MIN,
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};
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lzma_filter filters[2];
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filters[0].id = LZMA_FILTER_LZMA2;
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filters[0].options = &lzma2;
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filters[1].id = LZMA_VLI_UNKNOWN;
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// Set the above filter options to *block temporarily so that we can
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// encode the Block Header.
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lzma_filter *filters_orig = block->filters;
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block->filters = filters;
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if (lzma_block_header_size(block) != LZMA_OK) {
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block->filters = filters_orig;
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return LZMA_PROG_ERROR;
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}
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// Check that there's enough output space. The caller has already
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// set block->compressed_size to what lzma2_bound() has returned,
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// so we can reuse that value. We know that compressed_size is a
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// known valid VLI and header_size is a small value so their sum
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// will never overflow.
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assert(block->compressed_size == lzma2_bound(in_size));
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if (out_size - *out_pos
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< block->header_size + block->compressed_size) {
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block->filters = filters_orig;
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return LZMA_BUF_ERROR;
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}
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if (lzma_block_header_encode(block, out + *out_pos) != LZMA_OK) {
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block->filters = filters_orig;
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return LZMA_PROG_ERROR;
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}
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block->filters = filters_orig;
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*out_pos += block->header_size;
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// Encode the data using LZMA2 uncompressed chunks.
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size_t in_pos = 0;
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uint8_t control = 0x01; // Dictionary reset
|
||||
|
||||
while (in_pos < in_size) {
|
||||
// Control byte: Indicate uncompressed chunk, of which
|
||||
// the first resets the dictionary.
|
||||
out[(*out_pos)++] = control;
|
||||
control = 0x02; // No dictionary reset
|
||||
|
||||
// Size of the uncompressed chunk
|
||||
const size_t copy_size
|
||||
= MIN(in_size - in_pos, LZMA2_CHUNK_MAX);
|
||||
out[(*out_pos)++] = (copy_size - 1) >> 8;
|
||||
out[(*out_pos)++] = (copy_size - 1) & 0xFF;
|
||||
|
||||
// The actual data
|
||||
assert(*out_pos + copy_size <= out_size);
|
||||
memcpy(out + *out_pos, in + in_pos, copy_size);
|
||||
|
||||
in_pos += copy_size;
|
||||
*out_pos += copy_size;
|
||||
}
|
||||
|
||||
// End marker
|
||||
out[(*out_pos)++] = 0x00;
|
||||
assert(*out_pos <= out_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)
|
||||
{
|
||||
// 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;
|
||||
|
||||
const size_t 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.
|
||||
lzma_next_coder raw_encoder = LZMA_NEXT_CODER_INIT;
|
||||
lzma_ret 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;
|
||||
}
|
||||
|
||||
|
||||
extern LZMA_API lzma_ret
|
||||
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)
|
||||
{
|
||||
// Sanity checks
|
||||
if (block == NULL || block->filters == NULL
|
||||
|| (in == NULL && in_size != 0) || out == NULL
|
||||
|| out_pos == NULL || *out_pos > out_size)
|
||||
return LZMA_PROG_ERROR;
|
||||
|
||||
// Check the version field.
|
||||
if (block->version != 0)
|
||||
return LZMA_OPTIONS_ERROR;
|
||||
|
||||
// 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.
|
||||
const size_t check_size = lzma_check_size(block->check);
|
||||
if (check_size == UINT32_MAX)
|
||||
return LZMA_PROG_ERROR;
|
||||
|
||||
// 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.
|
||||
const lzma_ret 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 (size_t 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(out + *out_pos, check.buffer.u8, check_size);
|
||||
*out_pos += check_size;
|
||||
}
|
||||
|
||||
return LZMA_OK;
|
||||
}
|
|
@ -225,6 +225,27 @@ index_decoder_memconfig(lzma_coder *coder, uint64_t *memusage,
|
|||
}
|
||||
|
||||
|
||||
static lzma_ret
|
||||
index_decoder_reset(lzma_coder *coder, lzma_allocator *allocator,
|
||||
lzma_index **i, uint64_t memlimit)
|
||||
{
|
||||
// We always allocate a new lzma_index.
|
||||
*i = lzma_index_init(NULL, allocator);
|
||||
if (*i == NULL)
|
||||
return LZMA_MEM_ERROR;
|
||||
|
||||
// Initialize the rest.
|
||||
coder->sequence = SEQ_INDICATOR;
|
||||
coder->memlimit = memlimit;
|
||||
coder->index = *i;
|
||||
coder->count = 0; // Needs to be initialized due to _memconfig().
|
||||
coder->pos = 0;
|
||||
coder->crc32 = 0;
|
||||
|
||||
return LZMA_OK;
|
||||
}
|
||||
|
||||
|
||||
static lzma_ret
|
||||
index_decoder_init(lzma_next_coder *next, lzma_allocator *allocator,
|
||||
lzma_index **i, uint64_t memlimit)
|
||||
|
@ -247,20 +268,7 @@ index_decoder_init(lzma_next_coder *next, lzma_allocator *allocator,
|
|||
lzma_index_end(next->coder->index, allocator);
|
||||
}
|
||||
|
||||
// We always allocate a new lzma_index.
|
||||
*i = lzma_index_init(NULL, allocator);
|
||||
if (*i == NULL)
|
||||
return LZMA_MEM_ERROR;
|
||||
|
||||
// Initialize the rest.
|
||||
next->coder->sequence = SEQ_INDICATOR;
|
||||
next->coder->memlimit = memlimit;
|
||||
next->coder->index = *i;
|
||||
next->coder->count = 0; // Needs to be initialized due to _memconfig().
|
||||
next->coder->pos = 0;
|
||||
next->coder->crc32 = 0;
|
||||
|
||||
return LZMA_OK;
|
||||
return index_decoder_reset(next->coder, allocator, i, memlimit);
|
||||
}
|
||||
|
||||
|
||||
|
@ -273,3 +281,50 @@ lzma_index_decoder(lzma_stream *strm, lzma_index **i, uint64_t memlimit)
|
|||
|
||||
return LZMA_OK;
|
||||
}
|
||||
|
||||
|
||||
extern LZMA_API lzma_ret
|
||||
lzma_index_buffer_decode(
|
||||
lzma_index **i, uint64_t *memlimit, lzma_allocator *allocator,
|
||||
const uint8_t *in, size_t *in_pos, size_t in_size)
|
||||
{
|
||||
// Sanity checks
|
||||
if (i == NULL || in == NULL || in_pos == NULL || *in_pos > in_size)
|
||||
return LZMA_PROG_ERROR;
|
||||
|
||||
// Initialize the decoder.
|
||||
lzma_coder coder;
|
||||
return_if_error(index_decoder_reset(&coder, allocator, i, *memlimit));
|
||||
|
||||
// Store the input start position so that we can restore it in case
|
||||
// of an error.
|
||||
const size_t in_start = *in_pos;
|
||||
|
||||
// Do the actual decoding.
|
||||
lzma_ret ret = index_decode(&coder, allocator, in, in_pos, in_size,
|
||||
NULL, NULL, 0, LZMA_RUN);
|
||||
|
||||
if (ret == LZMA_STREAM_END) {
|
||||
ret = LZMA_OK;
|
||||
} else {
|
||||
// Something went wrong, free the Index structure and restore
|
||||
// the input position.
|
||||
lzma_index_end(*i, allocator);
|
||||
*i = NULL;
|
||||
*in_pos = in_start;
|
||||
|
||||
if (ret == LZMA_OK) {
|
||||
// The input is truncated or otherwise corrupt.
|
||||
// Use LZMA_DATA_ERROR instead of LZMA_BUF_ERROR
|
||||
// like lzma_vli_decode() does in single-call mode.
|
||||
ret = LZMA_DATA_ERROR;
|
||||
|
||||
} else if (ret == LZMA_MEMLIMIT_ERROR) {
|
||||
// Tell the caller how much memory would have
|
||||
// been needed.
|
||||
*memlimit = lzma_index_memusage(coder.count);
|
||||
}
|
||||
}
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
|
|
@ -178,6 +178,20 @@ index_encoder_end(lzma_coder *coder, lzma_allocator *allocator)
|
|||
}
|
||||
|
||||
|
||||
static void
|
||||
index_encoder_reset(lzma_coder *coder, lzma_index *i)
|
||||
{
|
||||
lzma_index_rewind(i);
|
||||
|
||||
coder->sequence = SEQ_INDICATOR;
|
||||
coder->index = i;
|
||||
coder->pos = 0;
|
||||
coder->crc32 = 0;
|
||||
|
||||
return;
|
||||
}
|
||||
|
||||
|
||||
extern lzma_ret
|
||||
lzma_index_encoder_init(lzma_next_coder *next, lzma_allocator *allocator,
|
||||
lzma_index *i)
|
||||
|
@ -196,12 +210,7 @@ lzma_index_encoder_init(lzma_next_coder *next, lzma_allocator *allocator,
|
|||
next->end = &index_encoder_end;
|
||||
}
|
||||
|
||||
lzma_index_rewind(i);
|
||||
|
||||
next->coder->sequence = SEQ_INDICATOR;
|
||||
next->coder->index = i;
|
||||
next->coder->pos = 0;
|
||||
next->coder->crc32 = 0;
|
||||
index_encoder_reset(next->coder, i);
|
||||
|
||||
return LZMA_OK;
|
||||
}
|
||||
|
@ -216,3 +225,41 @@ lzma_index_encoder(lzma_stream *strm, lzma_index *i)
|
|||
|
||||
return LZMA_OK;
|
||||
}
|
||||
|
||||
|
||||
extern LZMA_API lzma_ret
|
||||
lzma_index_buffer_encode(lzma_index *i,
|
||||
uint8_t *out, size_t *out_pos, size_t out_size)
|
||||
{
|
||||
// Validate the arugments.
|
||||
if (i == NULL || out == NULL || out_pos == NULL || *out_pos > out_size)
|
||||
return LZMA_PROG_ERROR;
|
||||
|
||||
// Don't try to encode if there's not enough output space.
|
||||
if (out_size - *out_pos < lzma_index_size(i))
|
||||
return LZMA_BUF_ERROR;
|
||||
|
||||
// The Index encoder needs just one small data structure so we can
|
||||
// allocate it on stack.
|
||||
lzma_coder coder;
|
||||
index_encoder_reset(&coder, i);
|
||||
|
||||
// Do the actual encoding. This should never fail, but store
|
||||
// the original *out_pos just in case.
|
||||
const size_t out_start = *out_pos;
|
||||
lzma_ret ret = index_encode(&coder, NULL, NULL, NULL, 0,
|
||||
out, out_pos, out_size, LZMA_RUN);
|
||||
|
||||
if (ret == LZMA_STREAM_END) {
|
||||
ret = LZMA_OK;
|
||||
} else {
|
||||
// We should never get here, but just in case, restore the
|
||||
// output position and set the error accordingly if something
|
||||
// goes wrong and debugging isn't enabled.
|
||||
assert(0);
|
||||
*out_pos = out_start;
|
||||
ret = LZMA_PROG_ERROR;
|
||||
}
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
|
|
@ -0,0 +1,138 @@
|
|||
///////////////////////////////////////////////////////////////////////////////
|
||||
//
|
||||
/// \file stream_buffer_encoder.c
|
||||
/// \brief Single-call .xz Stream encoder
|
||||
//
|
||||
// Copyright (C) 2009 Lasse Collin
|
||||
//
|
||||
// This library is free software; you can redistribute it and/or
|
||||
// modify it under the terms of the GNU Lesser General Public
|
||||
// License as published by the Free Software Foundation; either
|
||||
// version 2.1 of the License, or (at your option) any later version.
|
||||
//
|
||||
// This library is distributed in the hope that it will be useful,
|
||||
// but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
||||
// Lesser General Public License for more details.
|
||||
//
|
||||
///////////////////////////////////////////////////////////////////////////////
|
||||
|
||||
#include "index.h"
|
||||
|
||||
|
||||
/// Maximum size of Index that has exactly one Record.
|
||||
/// Index Indicator + Number of Records + Record + CRC32 rounded up to
|
||||
/// the next multiple of four.
|
||||
#define INDEX_BOUND ((1 + 1 + 2 * LZMA_VLI_BYTES_MAX + 4 + 3) & ~3)
|
||||
|
||||
/// Stream Header, Stream Footer, and Index
|
||||
#define HEADERS_BOUND (2 * LZMA_STREAM_HEADER_SIZE + INDEX_BOUND)
|
||||
|
||||
|
||||
extern LZMA_API size_t
|
||||
lzma_stream_buffer_bound(size_t uncompressed_size)
|
||||
{
|
||||
// Get the maximum possible size of a Block.
|
||||
const size_t block_bound = lzma_block_buffer_bound(uncompressed_size);
|
||||
if (block_bound == 0)
|
||||
return 0;
|
||||
|
||||
// Catch the possible integer overflow and also prevent the size of
|
||||
// the Stream exceeding LZMA_VLI_MAX (theoretically possible on
|
||||
// 64-bit systems).
|
||||
if (MIN(SIZE_MAX, LZMA_VLI_MAX) - block_bound < HEADERS_BOUND)
|
||||
return 0;
|
||||
|
||||
return block_bound + HEADERS_BOUND;
|
||||
}
|
||||
|
||||
|
||||
extern LZMA_API lzma_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;
|
||||
|
||||
// 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;
|
||||
|
||||
// Block
|
||||
lzma_block block = {
|
||||
.version = 0,
|
||||
.check = check,
|
||||
.filters = filters,
|
||||
};
|
||||
|
||||
return_if_error(lzma_block_buffer_encode(&block, allocator,
|
||||
in, in_size, out, &out_pos, out_size));
|
||||
|
||||
// Index
|
||||
{
|
||||
// Create an Index with one Record.
|
||||
lzma_index *i = lzma_index_init(NULL, NULL);
|
||||
if (i == NULL)
|
||||
return LZMA_MEM_ERROR;
|
||||
|
||||
lzma_ret ret = lzma_index_append(i, NULL,
|
||||
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, NULL);
|
||||
|
||||
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;
|
||||
}
|
|
@ -197,6 +197,30 @@ test_code(lzma_index *i)
|
|||
|
||||
lzma_index_hash_end(h, NULL);
|
||||
|
||||
// Encode buffer
|
||||
size_t buf_pos = 1;
|
||||
expect(lzma_index_buffer_encode(i, buf, &buf_pos, index_size)
|
||||
== LZMA_BUF_ERROR);
|
||||
expect(buf_pos == 1);
|
||||
|
||||
succeed(lzma_index_buffer_encode(i, buf, &buf_pos, index_size + 1));
|
||||
expect(buf_pos == index_size + 1);
|
||||
|
||||
// Decode buffer
|
||||
buf_pos = 1;
|
||||
uint64_t memlimit = MEMLIMIT;
|
||||
expect(lzma_index_buffer_decode(&d, &memlimit, NULL, buf, &buf_pos,
|
||||
index_size) == LZMA_DATA_ERROR);
|
||||
expect(buf_pos == 1);
|
||||
expect(d == NULL);
|
||||
|
||||
succeed(lzma_index_buffer_decode(&d, &memlimit, NULL, buf, &buf_pos,
|
||||
index_size + 1));
|
||||
expect(buf_pos == index_size + 1);
|
||||
expect(lzma_index_equal(i, d));
|
||||
|
||||
lzma_index_end(d, NULL);
|
||||
|
||||
free(buf);
|
||||
}
|
||||
|
||||
|
|
Loading…
Reference in New Issue