Index: xz/src/liblzma/api/lzma/block.h |
=================================================================== |
--- xz/src/liblzma/api/lzma/block.h (revision 0) |
+++ xz/src/liblzma/api/lzma/block.h (revision 0) |
@@ -0,0 +1,529 @@ |
+/** |
+ * \file lzma/block.h |
+ * \brief .xz Block handling |
+ */ |
+ |
+/* |
+ * Author: Lasse Collin |
+ * |
+ * This file has been put into the public domain. |
+ * You can do whatever you want with this file. |
+ * |
+ * See ../lzma.h for information about liblzma as a whole. |
+ */ |
+ |
+#ifndef LZMA_H_INTERNAL |
+# error Never include this file directly. Use <lzma.h> instead. |
+#endif |
+ |
+ |
+/** |
+ * \brief Options for the Block and Block Header encoders and decoders |
+ * |
+ * Different Block handling functions use different parts of this structure. |
+ * Some read some members, other functions write, and some do both. Only the |
+ * members listed for reading need to be initialized when the specified |
+ * functions are called. The members marked for writing will be assigned |
+ * new values at some point either by calling the given function or by |
+ * later calls to lzma_code(). |
+ */ |
+typedef struct { |
+ /** |
+ * \brief Block format version |
+ * |
+ * To prevent API and ABI breakages if new features are needed in |
+ * the Block field, a version number is used to indicate which |
+ * fields in this structure are in use. For now, version must always |
+ * be zero. With non-zero version, most Block related functions will |
+ * return LZMA_OPTIONS_ERROR. |
+ * |
+ * Read by: |
+ * - All functions that take pointer to lzma_block as argument, |
+ * including lzma_block_header_decode(). |
+ * |
+ * Written by: |
+ * - lzma_block_header_decode() |
+ */ |
+ uint32_t version; |
+ |
+ /** |
+ * \brief Size of the Block Header field |
+ * |
+ * This is always a multiple of four. |
+ * |
+ * Read by: |
+ * - lzma_block_header_encode() |
+ * - lzma_block_header_decode() |
+ * - lzma_block_compressed_size() |
+ * - lzma_block_unpadded_size() |
+ * - lzma_block_total_size() |
+ * - lzma_block_decoder() |
+ * - lzma_block_buffer_decode() |
+ * |
+ * Written by: |
+ * - lzma_block_header_size() |
+ * - lzma_block_buffer_encode() |
+ */ |
+ uint32_t header_size; |
+# define LZMA_BLOCK_HEADER_SIZE_MIN 8 |
+# define LZMA_BLOCK_HEADER_SIZE_MAX 1024 |
+ |
+ /** |
+ * \brief Type of integrity Check |
+ * |
+ * The Check ID is not stored into the Block Header, thus its value |
+ * must be provided also when decoding. |
+ * |
+ * Read by: |
+ * - lzma_block_header_encode() |
+ * - lzma_block_header_decode() |
+ * - lzma_block_compressed_size() |
+ * - lzma_block_unpadded_size() |
+ * - lzma_block_total_size() |
+ * - lzma_block_encoder() |
+ * - lzma_block_decoder() |
+ * - lzma_block_buffer_encode() |
+ * - lzma_block_buffer_decode() |
+ */ |
+ lzma_check check; |
+ |
+ /** |
+ * \brief Size of the Compressed Data in bytes |
+ * |
+ * Encoding: If this is not LZMA_VLI_UNKNOWN, Block Header encoder |
+ * will store this value to the Block Header. Block encoder doesn't |
+ * care about this value, but will set it once the encoding has been |
+ * finished. |
+ * |
+ * Decoding: If this is not LZMA_VLI_UNKNOWN, Block decoder will |
+ * verify that the size of the Compressed Data field matches |
+ * compressed_size. |
+ * |
+ * Usually you don't know this value when encoding in streamed mode, |
+ * and thus cannot write this field into the Block Header. |
+ * |
+ * In non-streamed mode you can reserve space for this field before |
+ * encoding the actual Block. After encoding the data, finish the |
+ * Block by encoding the Block Header. Steps in detail: |
+ * |
+ * - Set compressed_size to some big enough value. If you don't know |
+ * better, use LZMA_VLI_MAX, but remember that bigger values take |
+ * more space in Block Header. |
+ * |
+ * - Call lzma_block_header_size() to see how much space you need to |
+ * reserve for the Block Header. |
+ * |
+ * - Encode the Block using lzma_block_encoder() and lzma_code(). |
+ * It sets compressed_size to the correct value. |
+ * |
+ * - Use lzma_block_header_encode() to encode the Block Header. |
+ * Because space was reserved in the first step, you don't need |
+ * to call lzma_block_header_size() anymore, because due to |
+ * reserving, header_size has to be big enough. If it is "too big", |
+ * lzma_block_header_encode() will add enough Header Padding to |
+ * make Block Header to match the size specified by header_size. |
+ * |
+ * Read by: |
+ * - lzma_block_header_size() |
+ * - lzma_block_header_encode() |
+ * - lzma_block_compressed_size() |
+ * - lzma_block_unpadded_size() |
+ * - lzma_block_total_size() |
+ * - lzma_block_decoder() |
+ * - lzma_block_buffer_decode() |
+ * |
+ * Written by: |
+ * - lzma_block_header_decode() |
+ * - lzma_block_compressed_size() |
+ * - lzma_block_encoder() |
+ * - lzma_block_decoder() |
+ * - lzma_block_buffer_encode() |
+ * - lzma_block_buffer_decode() |
+ */ |
+ lzma_vli compressed_size; |
+ |
+ /** |
+ * \brief Uncompressed Size in bytes |
+ * |
+ * This is handled very similarly to compressed_size above. |
+ * |
+ * uncompressed_size is needed by fewer functions than |
+ * compressed_size. This is because uncompressed_size isn't |
+ * needed to validate that Block stays within proper limits. |
+ * |
+ * Read by: |
+ * - lzma_block_header_size() |
+ * - lzma_block_header_encode() |
+ * - lzma_block_decoder() |
+ * - lzma_block_buffer_decode() |
+ * |
+ * Written by: |
+ * - lzma_block_header_decode() |
+ * - lzma_block_encoder() |
+ * - lzma_block_decoder() |
+ * - lzma_block_buffer_encode() |
+ * - lzma_block_buffer_decode() |
+ */ |
+ lzma_vli uncompressed_size; |
+ |
+ /** |
+ * \brief Array of filters |
+ * |
+ * There can be 1-4 filters. The end of the array is marked with |
+ * .id = LZMA_VLI_UNKNOWN. |
+ * |
+ * Read by: |
+ * - lzma_block_header_size() |
+ * - lzma_block_header_encode() |
+ * - lzma_block_encoder() |
+ * - lzma_block_decoder() |
+ * - lzma_block_buffer_encode() |
+ * - lzma_block_buffer_decode() |
+ * |
+ * Written by: |
+ * - lzma_block_header_decode(): Note that this does NOT free() |
+ * the old filter options structures. All unused filters[] will |
+ * have .id == LZMA_VLI_UNKNOWN and .options == NULL. If |
+ * decoding fails, all filters[] are guaranteed to be |
+ * LZMA_VLI_UNKNOWN and NULL. |
+ * |
+ * \note Because of the array is terminated with |
+ * .id = LZMA_VLI_UNKNOWN, the actual array must |
+ * have LZMA_FILTERS_MAX + 1 members or the Block |
+ * Header decoder will overflow the buffer. |
+ */ |
+ lzma_filter *filters; |
+ |
+ /** |
+ * \brief Raw value stored in the Check field |
+ * |
+ * After successful coding, the first lzma_check_size(check) bytes |
+ * of this array contain the raw value stored in the Check field. |
+ * |
+ * Note that CRC32 and CRC64 are stored in little endian byte order. |
+ * Take it into account if you display the Check values to the user. |
+ * |
+ * Written by: |
+ * - lzma_block_encoder() |
+ * - lzma_block_decoder() |
+ * - lzma_block_buffer_encode() |
+ * - lzma_block_buffer_decode() |
+ */ |
+ uint8_t raw_check[LZMA_CHECK_SIZE_MAX]; |
+ |
+ /* |
+ * Reserved space to allow possible future extensions without |
+ * breaking the ABI. You should not touch these, because the names |
+ * of these variables may change. These are and will never be used |
+ * with the currently supported options, so it is safe to leave these |
+ * uninitialized. |
+ */ |
+ void *reserved_ptr1; |
+ void *reserved_ptr2; |
+ void *reserved_ptr3; |
+ uint32_t reserved_int1; |
+ uint32_t reserved_int2; |
+ lzma_vli reserved_int3; |
+ lzma_vli reserved_int4; |
+ lzma_vli reserved_int5; |
+ lzma_vli reserved_int6; |
+ lzma_vli reserved_int7; |
+ lzma_vli reserved_int8; |
+ lzma_reserved_enum reserved_enum1; |
+ lzma_reserved_enum reserved_enum2; |
+ lzma_reserved_enum reserved_enum3; |
+ lzma_reserved_enum reserved_enum4; |
+ lzma_bool reserved_bool1; |
+ lzma_bool reserved_bool2; |
+ lzma_bool reserved_bool3; |
+ lzma_bool reserved_bool4; |
+ lzma_bool reserved_bool5; |
+ lzma_bool reserved_bool6; |
+ lzma_bool reserved_bool7; |
+ lzma_bool reserved_bool8; |
+ |
+} lzma_block; |
+ |
+ |
+/** |
+ * \brief Decode the Block Header Size field |
+ * |
+ * To decode Block Header using lzma_block_header_decode(), the size of the |
+ * Block Header has to be known and stored into lzma_block.header_size. |
+ * The size can be calculated from the first byte of a Block using this macro. |
+ * Note that if the first byte is 0x00, it indicates beginning of Index; use |
+ * this macro only when the byte is not 0x00. |
+ * |
+ * There is no encoding macro, because Block Header encoder is enough for that. |
+ */ |
+#define lzma_block_header_size_decode(b) (((uint32_t)(b) + 1) * 4) |
+ |
+ |
+/** |
+ * \brief Calculate Block Header Size |
+ * |
+ * Calculate the minimum size needed for the Block Header field using the |
+ * settings specified in the lzma_block structure. Note that it is OK to |
+ * increase the calculated header_size value as long as it is a multiple of |
+ * four and doesn't exceed LZMA_BLOCK_HEADER_SIZE_MAX. Increasing header_size |
+ * just means that lzma_block_header_encode() will add Header Padding. |
+ * |
+ * \return - LZMA_OK: Size calculated successfully and stored to |
+ * block->header_size. |
+ * - LZMA_OPTIONS_ERROR: Unsupported version, filters or |
+ * filter options. |
+ * - LZMA_PROG_ERROR: Invalid values like compressed_size == 0. |
+ * |
+ * \note This doesn't check that all the options are valid i.e. this |
+ * may return LZMA_OK even if lzma_block_header_encode() or |
+ * lzma_block_encoder() would fail. If you want to validate the |
+ * filter chain, consider using lzma_memlimit_encoder() which as |
+ * a side-effect validates the filter chain. |
+ */ |
+extern LZMA_API(lzma_ret) lzma_block_header_size(lzma_block *block) |
+ lzma_nothrow lzma_attr_warn_unused_result; |
+ |
+ |
+/** |
+ * \brief Encode Block Header |
+ * |
+ * The caller must have calculated the size of the Block Header already with |
+ * lzma_block_header_size(). If a value larger than the one calculated by |
+ * lzma_block_header_size() is used, the Block Header will be padded to the |
+ * specified size. |
+ * |
+ * \param out Beginning of the output buffer. This must be |
+ * at least block->header_size bytes. |
+ * \param block Block options to be encoded. |
+ * |
+ * \return - LZMA_OK: Encoding was successful. block->header_size |
+ * bytes were written to output buffer. |
+ * - LZMA_OPTIONS_ERROR: Invalid or unsupported options. |
+ * - LZMA_PROG_ERROR: Invalid arguments, for example |
+ * block->header_size is invalid or block->filters is NULL. |
+ */ |
+extern LZMA_API(lzma_ret) lzma_block_header_encode( |
+ const lzma_block *block, uint8_t *out) |
+ lzma_nothrow lzma_attr_warn_unused_result; |
+ |
+ |
+/** |
+ * \brief Decode Block Header |
+ * |
+ * block->version should be set to the highest value supported by the |
+ * application; currently the only possible version is zero. This function |
+ * will set version to the lowest value that still supports all the features |
+ * required by the Block Header. |
+ * |
+ * The size of the Block Header must have already been decoded with |
+ * lzma_block_header_size_decode() macro and stored to block->header_size. |
+ * |
+ * block->filters must have been allocated, but not necessarily initialized. |
+ * Possible existing filter options are _not_ freed. |
+ * |
+ * \param block Destination for Block options. |
+ * \param allocator lzma_allocator for custom allocator functions. |
+ * Set to NULL to use malloc() (and also free() |
+ * if an error occurs). |
+ * \param in Beginning of the input buffer. This must be |
+ * at least block->header_size bytes. |
+ * |
+ * \return - LZMA_OK: Decoding was successful. block->header_size |
+ * bytes were read from the input buffer. |
+ * - LZMA_OPTIONS_ERROR: The Block Header specifies some |
+ * unsupported options such as unsupported filters. This can |
+ * happen also if block->version was set to a too low value |
+ * compared to what would be required to properly represent |
+ * the information stored in the Block Header. |
+ * - LZMA_DATA_ERROR: Block Header is corrupt, for example, |
+ * the CRC32 doesn't match. |
+ * - LZMA_PROG_ERROR: Invalid arguments, for example |
+ * block->header_size is invalid or block->filters is NULL. |
+ */ |
+extern LZMA_API(lzma_ret) lzma_block_header_decode(lzma_block *block, |
+ lzma_allocator *allocator, const uint8_t *in) |
+ lzma_nothrow lzma_attr_warn_unused_result; |
+ |
+ |
+/** |
+ * \brief Validate and set Compressed Size according to Unpadded Size |
+ * |
+ * Block Header stores Compressed Size, but Index has Unpadded Size. If the |
+ * application has already parsed the Index and is now decoding Blocks, |
+ * it can calculate Compressed Size from Unpadded Size. This function does |
+ * exactly that with error checking: |
+ * |
+ * - Compressed Size calculated from Unpadded Size must be positive integer, |
+ * that is, Unpadded Size must be big enough that after Block Header and |
+ * Check fields there's still at least one byte for Compressed Size. |
+ * |
+ * - If Compressed Size was present in Block Header, the new value |
+ * calculated from Unpadded Size is compared against the value |
+ * from Block Header. |
+ * |
+ * \note This function must be called _after_ decoding the Block Header |
+ * field so that it can properly validate Compressed Size if it |
+ * was present in Block Header. |
+ * |
+ * \return - LZMA_OK: block->compressed_size was set successfully. |
+ * - LZMA_DATA_ERROR: unpadded_size is too small compared to |
+ * block->header_size and lzma_check_size(block->check). |
+ * - LZMA_PROG_ERROR: Some values are invalid. For example, |
+ * block->header_size must be a multiple of four and |
+ * between 8 and 1024 inclusive. |
+ */ |
+extern LZMA_API(lzma_ret) lzma_block_compressed_size( |
+ lzma_block *block, lzma_vli unpadded_size) |
+ lzma_nothrow lzma_attr_warn_unused_result; |
+ |
+ |
+/** |
+ * \brief Calculate Unpadded Size |
+ * |
+ * The Index field stores Unpadded Size and Uncompressed Size. The latter |
+ * can be taken directly from the lzma_block structure after coding a Block, |
+ * but Unpadded Size needs to be calculated from Block Header Size, |
+ * Compressed Size, and size of the Check field. This is where this function |
+ * is needed. |
+ * |
+ * \return Unpadded Size on success, or zero on error. |
+ */ |
+extern LZMA_API(lzma_vli) lzma_block_unpadded_size(const lzma_block *block) |
+ lzma_nothrow lzma_attr_pure; |
+ |
+ |
+/** |
+ * \brief Calculate the total encoded size of a Block |
+ * |
+ * This is equivalent to lzma_block_unpadded_size() except that the returned |
+ * value includes the size of the Block Padding field. |
+ * |
+ * \return On success, total encoded size of the Block. On error, |
+ * zero is returned. |
+ */ |
+extern LZMA_API(lzma_vli) lzma_block_total_size(const lzma_block *block) |
+ lzma_nothrow lzma_attr_pure; |
+ |
+ |
+/** |
+ * \brief Initialize .xz Block encoder |
+ * |
+ * Valid actions for lzma_code() are LZMA_RUN, LZMA_SYNC_FLUSH (only if the |
+ * filter chain supports it), and LZMA_FINISH. |
+ * |
+ * \return - LZMA_OK: All good, continue with lzma_code(). |
+ * - LZMA_MEM_ERROR |
+ * - LZMA_OPTIONS_ERROR |
+ * - LZMA_UNSUPPORTED_CHECK: block->check specifies a Check ID |
+ * that is not supported by this buid of liblzma. Initializing |
+ * the encoder failed. |
+ * - LZMA_PROG_ERROR |
+ */ |
+extern LZMA_API(lzma_ret) lzma_block_encoder( |
+ lzma_stream *strm, lzma_block *block) |
+ lzma_nothrow lzma_attr_warn_unused_result; |
+ |
+ |
+/** |
+ * \brief Initialize .xz Block decoder |
+ * |
+ * Valid actions for lzma_code() are LZMA_RUN and LZMA_FINISH. Using |
+ * LZMA_FINISH is not required. It is supported only for convenience. |
+ * |
+ * \return - LZMA_OK: All good, continue with lzma_code(). |
+ * - LZMA_UNSUPPORTED_CHECK: Initialization was successful, but |
+ * the given Check ID is not supported, thus Check will be |
+ * ignored. |
+ * - LZMA_PROG_ERROR |
+ * - LZMA_MEM_ERROR |
+ */ |
+extern LZMA_API(lzma_ret) lzma_block_decoder( |
+ lzma_stream *strm, lzma_block *block) |
+ lzma_nothrow lzma_attr_warn_unused_result; |
+ |
+ |
+/** |
+ * \brief Calculate maximum output size for single-call Block encoding |
+ * |
+ * This is equivalent to lzma_stream_buffer_bound() but for .xz Blocks. |
+ * See the documentation of lzma_stream_buffer_bound(). |
+ */ |
+extern LZMA_API(size_t) lzma_block_buffer_bound(size_t uncompressed_size) |
+ lzma_nothrow; |
+ |
+ |
+/** |
+ * \brief Single-call .xz Block encoder |
+ * |
+ * In contrast to the multi-call encoder initialized with |
+ * lzma_block_encoder(), this function encodes also the Block Header. This |
+ * is required to make it possible to write appropriate Block Header also |
+ * in case the data isn't compressible, and different filter chain has to be |
+ * used to encode the data in uncompressed form using uncompressed chunks |
+ * of the LZMA2 filter. |
+ * |
+ * When the data isn't compressible, header_size, compressed_size, and |
+ * uncompressed_size are set just like when the data was compressible, but |
+ * it is possible that header_size is too small to hold the filter chain |
+ * specified in block->filters, because that isn't necessarily the filter |
+ * chain that was actually used to encode the data. lzma_block_unpadded_size() |
+ * still works normally, because it doesn't read the filters array. |
+ * |
+ * \param block Block options: block->version, block->check, |
+ * and block->filters must have been initialized. |
+ * \param allocator lzma_allocator for custom allocator functions. |
+ * Set to NULL to use malloc() and free(). |
+ * \param in Beginning of the input buffer |
+ * \param in_size Size of the input buffer |
+ * \param out Beginning of the output buffer |
+ * \param out_pos The next byte will be written to out[*out_pos]. |
+ * *out_pos is updated only if encoding succeeds. |
+ * \param out_size Size of the out buffer; the first byte into |
+ * which no data is written to is out[out_size]. |
+ * |
+ * \return - LZMA_OK: Encoding was successful. |
+ * - LZMA_BUF_ERROR: Not enough output buffer space. |
+ * - LZMA_OPTIONS_ERROR |
+ * - LZMA_MEM_ERROR |
+ * - LZMA_DATA_ERROR |
+ * - LZMA_PROG_ERROR |
+ */ |
+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) |
+ lzma_nothrow lzma_attr_warn_unused_result; |
+ |
+ |
+/** |
+ * \brief Single-call .xz Block decoder |
+ * |
+ * This is single-call equivalent of lzma_block_decoder(), and requires that |
+ * the caller has already decoded Block Header and checked its memory usage. |
+ * |
+ * \param block Block options just like with lzma_block_decoder(). |
+ * \param allocator lzma_allocator for custom allocator functions. |
+ * Set to NULL to use malloc() and free(). |
+ * \param in Beginning of the input buffer |
+ * \param in_pos The next byte will be read from in[*in_pos]. |
+ * *in_pos is updated only if decoding succeeds. |
+ * \param in_size Size of the input buffer; the first byte that |
+ * won't be read is in[in_size]. |
+ * \param out Beginning of the output buffer |
+ * \param out_pos The next byte will be written to out[*out_pos]. |
+ * *out_pos is updated only if encoding succeeds. |
+ * \param out_size Size of the out buffer; the first byte into |
+ * which no data is written to is out[out_size]. |
+ * |
+ * \return - LZMA_OK: Decoding was successful. |
+ * - LZMA_OPTIONS_ERROR |
+ * - LZMA_DATA_ERROR |
+ * - LZMA_MEM_ERROR |
+ * - LZMA_BUF_ERROR: Output buffer was too small. |
+ * - LZMA_PROG_ERROR |
+ */ |
+extern LZMA_API(lzma_ret) lzma_block_buffer_decode( |
+ lzma_block *block, 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) |
+ lzma_nothrow; |
Property changes on: xz/src/liblzma/api/lzma/block.h |
___________________________________________________________________ |
Added: svn:eol-style |
+ LF |