integrate lzma

[zpackage] / lzma / api / lzma / index_hash.h

diff --git a/lzma/api/lzma/index_hash.h b/lzma/api/lzma/index_hash.h
new file mode 100644 (file)
index 0000000..9287f1d
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+++ b/lzma/api/lzma/index_hash.h
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+/**
+ * \file        lzma/index_hash.h
+ * \brief       Validate Index by using a hash function
+ *
+ * Hashing makes it possible to use constant amount of memory to validate
+ * Index of arbitrary size.
+ */
+
+/*
+ * 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       Opaque data type to hold the Index hash
+ */
+typedef struct lzma_index_hash_s lzma_index_hash;
+
+
+/**
+ * \brief       Allocate and initialize a new lzma_index_hash structure
+ *
+ * If index_hash is NULL, a new lzma_index_hash structure is allocated,
+ * initialized, and a pointer to it returned. If allocation fails, NULL
+ * is returned.
+ *
+ * If index_hash is non-NULL, it is reinitialized and the same pointer
+ * returned. In this case, return value cannot be NULL or a different
+ * pointer than the index_hash that was given as an argument.
+ */
+extern LZMA_API(lzma_index_hash *) lzma_index_hash_init(
+               lzma_index_hash *index_hash, const lzma_allocator *allocator)
+               lzma_nothrow lzma_attr_warn_unused_result;
+
+
+/**
+ * \brief       Deallocate lzma_index_hash structure
+ */
+extern LZMA_API(void) lzma_index_hash_end(
+               lzma_index_hash *index_hash, const lzma_allocator *allocator)
+               lzma_nothrow;
+
+
+/**
+ * \brief       Add a new Record to an Index hash
+ *
+ * \param       index             Pointer to a lzma_index_hash structure
+ * \param       unpadded_size     Unpadded Size of a Block
+ * \param       uncompressed_size Uncompressed Size of a Block
+ *
+ * \return      - LZMA_OK
+ *              - LZMA_DATA_ERROR: Compressed or uncompressed size of the
+ *                Stream or size of the Index field would grow too big.
+ *              - LZMA_PROG_ERROR: Invalid arguments or this function is being
+ *                used when lzma_index_hash_decode() has already been used.
+ */
+extern LZMA_API(lzma_ret) lzma_index_hash_append(lzma_index_hash *index_hash,
+               lzma_vli unpadded_size, lzma_vli uncompressed_size)
+               lzma_nothrow lzma_attr_warn_unused_result;
+
+
+/**
+ * \brief       Decode and validate the Index field
+ *
+ * After telling the sizes of all Blocks with lzma_index_hash_append(),
+ * the actual Index field is decoded with this function. Specifically,
+ * once decoding of the Index field has been started, no more Records
+ * can be added using lzma_index_hash_append().
+ *
+ * This function doesn't use lzma_stream structure to pass the input data.
+ * Instead, the input buffer is specified using three arguments. This is
+ * because it matches better the internal APIs of liblzma.
+ *
+ * \param       index_hash      Pointer to a lzma_index_hash structure
+ * \param       in              Pointer to the beginning of the input buffer
+ * \param       in_pos          in[*in_pos] is the next byte to process
+ * \param       in_size         in[in_size] is the first byte not to process
+ *
+ * \return      - LZMA_OK: So far good, but more input is needed.
+ *              - LZMA_STREAM_END: Index decoded successfully and it matches
+ *                the Records given with lzma_index_hash_append().
+ *              - LZMA_DATA_ERROR: Index is corrupt or doesn't match the
+ *                information given with lzma_index_hash_append().
+ *              - LZMA_BUF_ERROR: Cannot progress because *in_pos >= in_size.
+ *              - LZMA_PROG_ERROR
+ */
+extern LZMA_API(lzma_ret) lzma_index_hash_decode(lzma_index_hash *index_hash,
+               const uint8_t *in, size_t *in_pos, size_t in_size)
+               lzma_nothrow lzma_attr_warn_unused_result;
+
+
+/**
+ * \brief       Get the size of the Index field as bytes
+ *
+ * This is needed to verify the Backward Size field in the Stream Footer.
+ */
+extern LZMA_API(lzma_vli) lzma_index_hash_size(
+               const lzma_index_hash *index_hash)
+               lzma_nothrow lzma_attr_pure;