b.liu | e958203 | 2025-04-17 19:18:16 +0800 | [diff] [blame^] | 1 | /////////////////////////////////////////////////////////////////////////////// |
| 2 | // |
| 3 | /// \file index.h |
| 4 | /// \brief Handling of Index |
| 5 | // |
| 6 | // Author: Lasse Collin |
| 7 | // |
| 8 | // This file has been put into the public domain. |
| 9 | // You can do whatever you want with this file. |
| 10 | // |
| 11 | /////////////////////////////////////////////////////////////////////////////// |
| 12 | |
| 13 | #ifndef LZMA_INDEX_H |
| 14 | #define LZMA_INDEX_H |
| 15 | |
| 16 | #include "common.h" |
| 17 | |
| 18 | |
| 19 | /// Minimum Unpadded Size |
| 20 | #define UNPADDED_SIZE_MIN LZMA_VLI_C(5) |
| 21 | |
| 22 | /// Maximum Unpadded Size |
| 23 | #define UNPADDED_SIZE_MAX (LZMA_VLI_MAX & ~LZMA_VLI_C(3)) |
| 24 | |
| 25 | |
| 26 | /// Get the size of the Index Padding field. This is needed by Index encoder |
| 27 | /// and decoder, but applications should have no use for this. |
| 28 | extern uint32_t lzma_index_padding_size(const lzma_index *i); |
| 29 | |
| 30 | |
| 31 | /// Set for how many Records to allocate memory the next time |
| 32 | /// lzma_index_append() needs to allocate space for a new Record. |
| 33 | /// This is used only by the Index decoder. |
| 34 | extern void lzma_index_prealloc(lzma_index *i, lzma_vli records); |
| 35 | |
| 36 | |
| 37 | /// Round the variable-length integer to the next multiple of four. |
| 38 | static inline lzma_vli |
| 39 | vli_ceil4(lzma_vli vli) |
| 40 | { |
| 41 | assert(vli <= LZMA_VLI_MAX); |
| 42 | return (vli + 3) & ~LZMA_VLI_C(3); |
| 43 | } |
| 44 | |
| 45 | |
| 46 | /// Calculate the size of the Index field excluding Index Padding |
| 47 | static inline lzma_vli |
| 48 | index_size_unpadded(lzma_vli count, lzma_vli index_list_size) |
| 49 | { |
| 50 | // Index Indicator + Number of Records + List of Records + CRC32 |
| 51 | return 1 + lzma_vli_size(count) + index_list_size + 4; |
| 52 | } |
| 53 | |
| 54 | |
| 55 | /// Calculate the size of the Index field including Index Padding |
| 56 | static inline lzma_vli |
| 57 | index_size(lzma_vli count, lzma_vli index_list_size) |
| 58 | { |
| 59 | return vli_ceil4(index_size_unpadded(count, index_list_size)); |
| 60 | } |
| 61 | |
| 62 | |
| 63 | /// Calculate the total size of the Stream |
| 64 | static inline lzma_vli |
| 65 | index_stream_size(lzma_vli blocks_size, |
| 66 | lzma_vli count, lzma_vli index_list_size) |
| 67 | { |
| 68 | return LZMA_STREAM_HEADER_SIZE + blocks_size |
| 69 | + index_size(count, index_list_size) |
| 70 | + LZMA_STREAM_HEADER_SIZE; |
| 71 | } |
| 72 | |
| 73 | #endif |