lzma_.check
Integrity checks Source:Author:
Lasse Collin (original liblzma author), Johannes Pfau (D bindings) License:
public domain
- enum lzma_check;
- Type of the integrity check (Check ID)
The .xz format supports multiple types of checks that are calculated
from the uncompressed data. They vary in both speed and ability to
detect errors.
- LZMA_CHECK_NONE
- No Check is calculated. Size of the Check field: 0 bytes
- LZMA_CHECK_CRC32
- CRC32 using the polynomial from the IEEE 802.3 standard Size of the Check field: 4 bytes
- LZMA_CHECK_CRC64
- CRC64 using the polynomial from the ECMA-182 standard Size of the Check field: 8 bytes
- LZMA_CHECK_SHA256
- SHA-256 Size of the Check field: 32 bytes
- int LZMA_CHECK_ID_MAX;
- Maximum valid Check ID The .xz file format specification specifies 16 Check IDs (0-15). Some of them are only reserved, that is, no actual Check algorithm has been assigned. When decoding, liblzma still accepts unknown Check IDs for future compatibility. If a valid but unsupported Check ID is detected, liblzma can indicate a warning; see the flags LZMA_TELL_NO_CHECK, LZMA_TELL_UNSUPPORTED_CHECK, and LZMA_TELL_ANY_CHECK in container.h.
- lzma_bool lzma_check_is_supported(lzma_check check);
- Test if the given Check ID is supported Return true if the given Check ID is supported by this liblzma build. Otherwise false is returned. It is safe to call this with a value that is not in the range [0, 15]; in that case the return value is always false. You can assume that LZMA_CHECK_NONE and LZMA_CHECK_CRC32 are always supported (even if liblzma is built with limited features).
- uint lzma_check_size(lzma_check check);
- Get the size of the Check field with the given Check ID Although not all Check IDs have a check algorithm associated, the size of every Check is already frozen. This function returns the size (in bytes) of the Check field with the specified Check ID. The values are: { 0, 4, 4, 4, 8, 8, 8, 16, 16, 16, 32, 32, 32, 64, 64, 64 } If the argument is not in the range [0, 15], UINT32_MAX is returned.
- int LZMA_CHECK_SIZE_MAX;
- Maximum size of a Check field
- uint lzma_crc32(const(ubyte)* buf, size_t size, uint crc);
- Calculate CRC32
Calculate CRC32 using the polynomial from the IEEE 802.3 standard.
Parameters:
Returns:const(ubyte)* buf Pointer to the input buffer size_t size Size of the input buffer uint crc Previously returned CRC value. This is used to calculate the CRC of a big buffer in smaller chunks. Set to zero when starting a new calculation.
Updated CRC value, which can be passed to this function again to continue CRC calculation. - ulong lzma_crc64(const(ubyte)* buf, size_t size, ulong crc);
- \brief Calculate CRC64 Calculate CRC64 using the polynomial from the ECMA-182 standard. This function is used similarly to lzma_crc32(). See its documentation.
- lzma_check lzma_get_check(const lzma_stream* strm);
- Get the type of the integrity check This function can be called only immediately after lzma_code() has returned LZMA_NO_CHECK, LZMA_UNSUPPORTED_CHECK, or LZMA_GET_CHECK. Calling this function in any other situation has undefined behavior.