root / lab4 / .minix-src / include / lzma / index_hash.h @ 13
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| 1 | 13 | up20180614 | /**
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| 2 | * \file lzma/index_hash.h
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| 3 | * \brief Validate Index by using a hash function
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| 4 | *
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| 5 | * Hashing makes it possible to use constant amount of memory to validate
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| 6 | * Index of arbitrary size.
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| 7 | */
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| 8 | |||
| 9 | /*
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| 10 | * Author: Lasse Collin
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| 11 | *
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| 12 | * This file has been put into the public domain.
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| 13 | * You can do whatever you want with this file.
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| 14 | *
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| 15 | * See ../lzma.h for information about liblzma as a whole.
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| 16 | */
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| 17 | |||
| 18 | #ifndef LZMA_H_INTERNAL
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| 19 | # error Never include this file directly. Use <lzma.h> instead.
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| 20 | #endif
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| 21 | |||
| 22 | /**
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| 23 | * \brief Opaque data type to hold the Index hash
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| 24 | */
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| 25 | typedef struct lzma_index_hash_s lzma_index_hash; |
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| 26 | |||
| 27 | |||
| 28 | /**
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| 29 | * \brief Allocate and initialize a new lzma_index_hash structure
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| 30 | *
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| 31 | * If index_hash is NULL, a new lzma_index_hash structure is allocated,
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| 32 | * initialized, and a pointer to it returned. If allocation fails, NULL
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| 33 | * is returned.
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| 34 | *
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| 35 | * If index_hash is non-NULL, it is reinitialized and the same pointer
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| 36 | * returned. In this case, return value cannot be NULL or a different
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| 37 | * pointer than the index_hash that was given as an argument.
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| 38 | */
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| 39 | extern LZMA_API(lzma_index_hash *) lzma_index_hash_init(
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| 40 | lzma_index_hash *index_hash, const lzma_allocator *allocator)
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| 41 | lzma_nothrow lzma_attr_warn_unused_result; |
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| 42 | |||
| 43 | |||
| 44 | /**
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| 45 | * \brief Deallocate lzma_index_hash structure
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| 46 | */
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| 47 | extern LZMA_API(void) lzma_index_hash_end( |
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| 48 | lzma_index_hash *index_hash, const lzma_allocator *allocator)
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| 49 | lzma_nothrow; |
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| 50 | |||
| 51 | |||
| 52 | /**
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| 53 | * \brief Add a new Record to an Index hash
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| 54 | *
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| 55 | * \param index Pointer to a lzma_index_hash structure
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| 56 | * \param unpadded_size Unpadded Size of a Block
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| 57 | * \param uncompressed_size Uncompressed Size of a Block
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| 58 | *
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| 59 | * \return - LZMA_OK
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| 60 | * - LZMA_DATA_ERROR: Compressed or uncompressed size of the
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| 61 | * Stream or size of the Index field would grow too big.
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| 62 | * - LZMA_PROG_ERROR: Invalid arguments or this function is being
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| 63 | * used when lzma_index_hash_decode() has already been used.
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| 64 | */
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| 65 | extern LZMA_API(lzma_ret) lzma_index_hash_append(lzma_index_hash *index_hash,
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| 66 | lzma_vli unpadded_size, lzma_vli uncompressed_size) |
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| 67 | lzma_nothrow lzma_attr_warn_unused_result; |
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| 68 | |||
| 69 | |||
| 70 | /**
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| 71 | * \brief Decode and validate the Index field
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| 72 | *
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| 73 | * After telling the sizes of all Blocks with lzma_index_hash_append(),
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| 74 | * the actual Index field is decoded with this function. Specifically,
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| 75 | * once decoding of the Index field has been started, no more Records
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| 76 | * can be added using lzma_index_hash_append().
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| 77 | *
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| 78 | * This function doesn't use lzma_stream structure to pass the input data.
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| 79 | * Instead, the input buffer is specified using three arguments. This is
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| 80 | * because it matches better the internal APIs of liblzma.
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| 81 | *
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| 82 | * \param index_hash Pointer to a lzma_index_hash structure
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| 83 | * \param in Pointer to the beginning of the input buffer
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| 84 | * \param in_pos in[*in_pos] is the next byte to process
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| 85 | * \param in_size in[in_size] is the first byte not to process
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| 86 | *
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| 87 | * \return - LZMA_OK: So far good, but more input is needed.
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| 88 | * - LZMA_STREAM_END: Index decoded successfully and it matches
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| 89 | * the Records given with lzma_index_hash_append().
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| 90 | * - LZMA_DATA_ERROR: Index is corrupt or doesn't match the
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| 91 | * information given with lzma_index_hash_append().
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| 92 | * - LZMA_BUF_ERROR: Cannot progress because *in_pos >= in_size.
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| 93 | * - LZMA_PROG_ERROR
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| 94 | */
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| 95 | extern LZMA_API(lzma_ret) lzma_index_hash_decode(lzma_index_hash *index_hash,
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| 96 | const uint8_t *in, size_t *in_pos, size_t in_size)
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| 97 | lzma_nothrow lzma_attr_warn_unused_result; |
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| 98 | |||
| 99 | |||
| 100 | /**
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| 101 | * \brief Get the size of the Index field as bytes
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| 102 | *
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| 103 | * This is needed to verify the Backward Size field in the Stream Footer.
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| 104 | */
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| 105 | extern LZMA_API(lzma_vli) lzma_index_hash_size(
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| 106 | const lzma_index_hash *index_hash)
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| 107 | lzma_nothrow lzma_attr_pure; |