224 lines
8.3 KiB
C
224 lines
8.3 KiB
C
|
/**
|
||
|
|
* \file lzma/stream_flags.h
|
||
|
|
* \brief .xz Stream Header and Stream Footer encoder and decoder
|
||
|
|
*/
|
||
|
|
|
||
|
|
/*
|
||
|
|
* 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 Size of Stream Header and Stream Footer
|
||
|
|
*
|
||
|
|
* Stream Header and Stream Footer have the same size and they are not
|
||
|
|
* going to change even if a newer version of the .xz file format is
|
||
|
|
* developed in future.
|
||
|
|
*/
|
||
|
|
#define LZMA_STREAM_HEADER_SIZE 12
|
||
|
|
|
||
|
|
|
||
|
|
/**
|
||
|
|
* \brief Options for encoding/decoding Stream Header and Stream Footer
|
||
|
|
*/
|
||
|
|
typedef struct {
|
||
|
|
/**
|
||
|
|
* \brief Stream Flags format version
|
||
|
|
*
|
||
|
|
* To prevent API and ABI breakages if new features are needed in
|
||
|
|
* Stream Header or Stream Footer, 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, the
|
||
|
|
* lzma_stream_header_encode() and lzma_stream_footer_encode()
|
||
|
|
* will return LZMA_OPTIONS_ERROR.
|
||
|
|
*
|
||
|
|
* lzma_stream_header_decode() and lzma_stream_footer_decode()
|
||
|
|
* will always set this to the lowest value that supports all the
|
||
|
|
* features indicated by the Stream Flags field. The application
|
||
|
|
* must check that the version number set by the decoding functions
|
||
|
|
* is supported by the application. Otherwise it is possible that
|
||
|
|
* the application will decode the Stream incorrectly.
|
||
|
|
*/
|
||
|
|
uint32_t version;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* \brief Backward Size
|
||
|
|
*
|
||
|
|
* Backward Size must be a multiple of four bytes. In this Stream
|
||
|
|
* format version, Backward Size is the size of the Index field.
|
||
|
|
*
|
||
|
|
* Backward Size isn't actually part of the Stream Flags field, but
|
||
|
|
* it is convenient to include in this structure anyway. Backward
|
||
|
|
* Size is present only in the Stream Footer. There is no need to
|
||
|
|
* initialize backward_size when encoding Stream Header.
|
||
|
|
*
|
||
|
|
* lzma_stream_header_decode() always sets backward_size to
|
||
|
|
* LZMA_VLI_UNKNOWN so that it is convenient to use
|
||
|
|
* lzma_stream_flags_compare() when both Stream Header and Stream
|
||
|
|
* Footer have been decoded.
|
||
|
|
*/
|
||
|
|
lzma_vli backward_size;
|
||
|
|
# define LZMA_BACKWARD_SIZE_MIN 4
|
||
|
|
# define LZMA_BACKWARD_SIZE_MAX (LZMA_VLI_C(1) << 34)
|
||
|
|
|
||
|
|
/**
|
||
|
|
* \brief Check ID
|
||
|
|
*
|
||
|
|
* This indicates the type of the integrity check calculated from
|
||
|
|
* uncompressed data.
|
||
|
|
*/
|
||
|
|
lzma_check check;
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Reserved space to allow possible future extensions without
|
||
|
|
* breaking the ABI. You should not touch these, because the
|
||
|
|
* names of these variables may change.
|
||
|
|
*
|
||
|
|
* (We will never be able to use all of these since Stream Flags
|
||
|
|
* is just two bytes plus Backward Size of four bytes. But it's
|
||
|
|
* nice to have the proper types when they are needed.)
|
||
|
|
*/
|
||
|
|
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;
|
||
|
|
uint32_t reserved_int1;
|
||
|
|
uint32_t reserved_int2;
|
||
|
|
|
||
|
|
} lzma_stream_flags;
|
||
|
|
|
||
|
|
|
||
|
|
/**
|
||
|
|
* \brief Encode Stream Header
|
||
|
|
*
|
||
|
|
* \param options Stream Header options to be encoded.
|
||
|
|
* options->backward_size is ignored and doesn't
|
||
|
|
* need to be initialized.
|
||
|
|
* \param out Beginning of the output buffer of
|
||
|
|
* LZMA_STREAM_HEADER_SIZE bytes.
|
||
|
|
*
|
||
|
|
* \return - LZMA_OK: Encoding was successful.
|
||
|
|
* - LZMA_OPTIONS_ERROR: options->version is not supported by
|
||
|
|
* this liblzma version.
|
||
|
|
* - LZMA_PROG_ERROR: Invalid options.
|
||
|
|
*/
|
||
|
|
extern LZMA_API(lzma_ret) lzma_stream_header_encode(
|
||
|
|
const lzma_stream_flags *options, uint8_t *out)
|
||
|
|
lzma_nothrow lzma_attr_warn_unused_result;
|
||
|
|
|
||
|
|
|
||
|
|
/**
|
||
|
|
* \brief Encode Stream Footer
|
||
|
|
*
|
||
|
|
* \param options Stream Footer options to be encoded.
|
||
|
|
* \param out Beginning of the output buffer of
|
||
|
|
* LZMA_STREAM_HEADER_SIZE bytes.
|
||
|
|
*
|
||
|
|
* \return - LZMA_OK: Encoding was successful.
|
||
|
|
* - LZMA_OPTIONS_ERROR: options->version is not supported by
|
||
|
|
* this liblzma version.
|
||
|
|
* - LZMA_PROG_ERROR: Invalid options.
|
||
|
|
*/
|
||
|
|
extern LZMA_API(lzma_ret) lzma_stream_footer_encode(
|
||
|
|
const lzma_stream_flags *options, uint8_t *out)
|
||
|
|
lzma_nothrow lzma_attr_warn_unused_result;
|
||
|
|
|
||
|
|
|
||
|
|
/**
|
||
|
|
* \brief Decode Stream Header
|
||
|
|
*
|
||
|
|
* \param options Target for the decoded Stream Header options.
|
||
|
|
* \param in Beginning of the input buffer of
|
||
|
|
* LZMA_STREAM_HEADER_SIZE bytes.
|
||
|
|
*
|
||
|
|
* options->backward_size is always set to LZMA_VLI_UNKNOWN. This is to
|
||
|
|
* help comparing Stream Flags from Stream Header and Stream Footer with
|
||
|
|
* lzma_stream_flags_compare().
|
||
|
|
*
|
||
|
|
* \return - LZMA_OK: Decoding was successful.
|
||
|
|
* - LZMA_FORMAT_ERROR: Magic bytes don't match, thus the given
|
||
|
|
* buffer cannot be Stream Header.
|
||
|
|
* - LZMA_DATA_ERROR: CRC32 doesn't match, thus the header
|
||
|
|
* is corrupt.
|
||
|
|
* - LZMA_OPTIONS_ERROR: Unsupported options are present
|
||
|
|
* in the header.
|
||
|
|
*
|
||
|
|
* \note When decoding .xz files that contain multiple Streams, it may
|
||
|
|
* make sense to print "file format not recognized" only if
|
||
|
|
* decoding of the Stream Header of the _first_ Stream gives
|
||
|
|
* LZMA_FORMAT_ERROR. If non-first Stream Header gives
|
||
|
|
* LZMA_FORMAT_ERROR, the message used for LZMA_DATA_ERROR is
|
||
|
|
* probably more appropriate.
|
||
|
|
*
|
||
|
|
* For example, Stream decoder in liblzma uses LZMA_DATA_ERROR if
|
||
|
|
* LZMA_FORMAT_ERROR is returned by lzma_stream_header_decode()
|
||
|
|
* when decoding non-first Stream.
|
||
|
|
*/
|
||
|
|
extern LZMA_API(lzma_ret) lzma_stream_header_decode(
|
||
|
|
lzma_stream_flags *options, const uint8_t *in)
|
||
|
|
lzma_nothrow lzma_attr_warn_unused_result;
|
||
|
|
|
||
|
|
|
||
|
|
/**
|
||
|
|
* \brief Decode Stream Footer
|
||
|
|
*
|
||
|
|
* \param options Target for the decoded Stream Header options.
|
||
|
|
* \param in Beginning of the input buffer of
|
||
|
|
* LZMA_STREAM_HEADER_SIZE bytes.
|
||
|
|
*
|
||
|
|
* \return - LZMA_OK: Decoding was successful.
|
||
|
|
* - LZMA_FORMAT_ERROR: Magic bytes don't match, thus the given
|
||
|
|
* buffer cannot be Stream Footer.
|
||
|
|
* - LZMA_DATA_ERROR: CRC32 doesn't match, thus the Stream Footer
|
||
|
|
* is corrupt.
|
||
|
|
* - LZMA_OPTIONS_ERROR: Unsupported options are present
|
||
|
|
* in Stream Footer.
|
||
|
|
*
|
||
|
|
* \note If Stream Header was already decoded successfully, but
|
||
|
|
* decoding Stream Footer returns LZMA_FORMAT_ERROR, the
|
||
|
|
* application should probably report some other error message
|
||
|
|
* than "file format not recognized", since the file more likely
|
||
|
|
* is corrupt (possibly truncated). Stream decoder in liblzma
|
||
|
|
* uses LZMA_DATA_ERROR in this situation.
|
||
|
|
*/
|
||
|
|
extern LZMA_API(lzma_ret) lzma_stream_footer_decode(
|
||
|
|
lzma_stream_flags *options, const uint8_t *in)
|
||
|
|
lzma_nothrow lzma_attr_warn_unused_result;
|
||
|
|
|
||
|
|
|
||
|
|
/**
|
||
|
|
* \brief Compare two lzma_stream_flags structures
|
||
|
|
*
|
||
|
|
* backward_size values are compared only if both are not
|
||
|
|
* LZMA_VLI_UNKNOWN.
|
||
|
|
*
|
||
|
|
* \return - LZMA_OK: Both are equal. If either had backward_size set
|
||
|
|
* to LZMA_VLI_UNKNOWN, backward_size values were not
|
||
|
|
* compared or validated.
|
||
|
|
* - LZMA_DATA_ERROR: The structures differ.
|
||
|
|
* - LZMA_OPTIONS_ERROR: version in either structure is greater
|
||
|
|
* than the maximum supported version (currently zero).
|
||
|
|
* - LZMA_PROG_ERROR: Invalid value, e.g. invalid check or
|
||
|
|
* backward_size.
|
||
|
|
*/
|
||
|
|
extern LZMA_API(lzma_ret) lzma_stream_flags_compare(
|
||
|
|
const lzma_stream_flags *a, const lzma_stream_flags *b)
|
||
|
|
lzma_nothrow lzma_attr_pure;
|