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181 | pragma Style_Checks (Off);
with Interfaces.C; use Interfaces.C;
with Ada.Streams;
with Lzma.Base;
package Lzma.Vli is
-- unsupported macro: LZMA_VLI_MAX (UINT64_MAX / 2)
-- unsupported macro: LZMA_VLI_UNKNOWN UINT64_MAX
LZMA_VLI_BYTES_MAX : constant := 9; -- /usr/include/lzma/vli.h:44
-- arg-macro: procedure LZMA_VLI_C UINT64_C(n)
-- UINT64_C(n)
-- arg-macro: function lzma_vli_is_valid ((vli) <= LZMA_VLI_MAX or else (vli) = LZMA_VLI_UNKNOWN
-- return (vli) <= LZMA_VLI_MAX or else (vli) = LZMA_VLI_UNKNOWN;
--*
-- * \file lzma/vli.h
-- * \brief Variable-length integer handling
-- *
-- * In the .xz format, most integers are encoded in a variable-length
-- * representation, which is sometimes called little endian base-128 encoding.
-- * This saves space when smaller values are more likely than bigger values.
-- *
-- * The encoding scheme encodes seven bits to every byte, using minimum
-- * number of bytes required to represent the given value. Encodings that use
-- * non-minimum number of bytes are invalid, thus every integer has exactly
-- * one encoded representation. The maximum number of bits in a VLI is 63,
-- * thus the vli argument must be less than or equal to UINT64_MAX / 2. You
-- * should use LZMA_VLI_MAX for clarity.
--
-- * 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.
--
--*
-- * \brief Maximum supported value of a variable-length integer
--
--*
-- * \brief VLI value to denote that the value is unknown
--
--*
-- * \brief Maximum supported encoded length of variable length integers
--
--*
-- * \brief VLI constant suffix
--
--*
-- * \brief Variable-length integer type
-- *
-- * Valid VLI values are in the range [0, LZMA_VLI_MAX]. Unknown value is
-- * indicated with LZMA_VLI_UNKNOWN, which is the maximum value of the
-- * underlaying integer type.
-- *
-- * lzma_vli will be uint64_t for the foreseeable future. If a bigger size
-- * is needed in the future, it is guaranteed that 2 * LZMA_VLI_MAX will
-- * not overflow lzma_vli. This simplifies integer overflow detection.
--
subtype lzma_vli is Long_Long_Integer; -- /usr/include/lzma/vli.h:63
--*
-- * \brief Validate a variable-length integer
-- *
-- * This is useful to test that application has given acceptable values
-- * for example in the uncompressed_size and compressed_size variables.
-- *
-- * \return True if the integer is representable as VLI or if it
-- * indicates unknown value.
--
--*
-- * \brief Encode a variable-length integer
-- *
-- * This function has two modes: single-call and multi-call. Single-call mode
-- * encodes the whole integer at once; it is an error if the output buffer is
-- * too small. Multi-call mode saves the position in *vli_pos, and thus it is
-- * possible to continue encoding if the buffer becomes full before the whole
-- * integer has been encoded.
-- *
-- * \param vli Integer to be encoded
-- * \param vli_pos How many VLI-encoded bytes have already been written
-- * out. When starting to encode a new integer in
-- * multi-call mode, *vli_pos must be set to zero.
-- * To use single-call encoding, set vli_pos to NULL.
-- * \param out Beginning of the output buffer
-- * \param out_pos The next byte will be written to out[*out_pos].
-- * \param out_size Size of the out buffer; the first byte into
-- * which no data is written to is out[out_size].
-- *
-- * \return Slightly different return values are used in multi-call and
-- * single-call modes.
-- *
-- * Single-call (vli_pos == NULL):
-- * - LZMA_OK: Integer successfully encoded.
-- * - LZMA_PROG_ERROR: Arguments are not sane. This can be due
-- * to too little output space; single-call mode doesn't use
-- * LZMA_BUF_ERROR, since the application should have checked
-- * the encoded size with lzma_vli_size().
-- *
-- * Multi-call (vli_pos != NULL):
-- * - LZMA_OK: So far all OK, but the integer is not
-- * completely written out yet.
-- * - LZMA_STREAM_END: Integer successfully encoded.
-- * - LZMA_BUF_ERROR: No output space was provided.
-- * - LZMA_PROG_ERROR: Arguments are not sane.
--
function lzma_vli_encode
(vli : lzma_vli;
vli_pos : access Interfaces.C.size_t;
c_out : access Ada.Streams.Stream_Element;
out_pos : access Interfaces.C.size_t;
out_size : Interfaces.C.size_t) return Lzma.Base.lzma_ret; -- /usr/include/lzma/vli.h:115
pragma Import (C, lzma_vli_encode, "lzma_vli_encode");
--*
-- * \brief Decode a variable-length integer
-- *
-- * Like lzma_vli_encode(), this function has single-call and multi-call modes.
-- *
-- * \param vli Pointer to decoded integer. The decoder will
-- * initialize it to zero when *vli_pos == 0, so
-- * application isn't required to initialize *vli.
-- * \param vli_pos How many bytes have already been decoded. When
-- * starting to decode a new integer in multi-call
-- * mode, *vli_pos must be initialized to zero. To
-- * use single-call decoding, set vli_pos to NULL.
-- * \param in Beginning of the input buffer
-- * \param in_pos The next byte will be read from in[*in_pos].
-- * \param in_size Size of the input buffer; the first byte that
-- * won't be read is in[in_size].
-- *
-- * \return Slightly different return values are used in multi-call and
-- * single-call modes.
-- *
-- * Single-call (vli_pos == NULL):
-- * - LZMA_OK: Integer successfully decoded.
-- * - LZMA_DATA_ERROR: Integer is corrupt. This includes hitting
-- * the end of the input buffer before the whole integer was
-- * decoded; providing no input at all will use LZMA_DATA_ERROR.
-- * - LZMA_PROG_ERROR: Arguments are not sane.
-- *
-- * Multi-call (vli_pos != NULL):
-- * - LZMA_OK: So far all OK, but the integer is not
-- * completely decoded yet.
-- * - LZMA_STREAM_END: Integer successfully decoded.
-- * - LZMA_DATA_ERROR: Integer is corrupt.
-- * - LZMA_BUF_ERROR: No input was provided.
-- * - LZMA_PROG_ERROR: Arguments are not sane.
--
function lzma_vli_decode
(vli : access lzma_vli;
vli_pos : access Interfaces.C.size_t;
c_in : access Ada.Streams.Stream_Element;
in_pos : access Interfaces.C.size_t;
in_size : Interfaces.C.size_t) return Lzma.Base.lzma_ret; -- /usr/include/lzma/vli.h:154
pragma Import (C, lzma_vli_decode, "lzma_vli_decode");
--*
-- * \brief Get the number of bytes required to encode a VLI
-- *
-- * \return Number of bytes on success (1-9). If vli isn't valid,
-- * zero is returned.
--
function lzma_vli_size (vli : lzma_vli) return Interfaces.C.unsigned; -- /usr/include/lzma/vli.h:165
pragma Import (C, lzma_vli_size, "lzma_vli_size");
end Lzma.Vli;
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