1 /////////////////////////////////////////////////////////////////////////////// 2 // 3 /// \file index.h 4 /// \brief Handling of Index 5 /// \note This header file does not include common.h or lzma.h because 6 /// this file is needed by both liblzma internally and by the 7 /// tests. Including common.h will include and define many things 8 /// the tests do not need and prevents issues with header file 9 /// include order. This way, if lzma.h or common.h are not 10 /// included before this file it will break on every OS instead 11 /// of causing more subtle errors. 12 // 13 // Author: Lasse Collin 14 // 15 // This file has been put into the public domain. 16 // You can do whatever you want with this file. 17 // 18 /////////////////////////////////////////////////////////////////////////////// 19 20 #ifndef LZMA_INDEX_H 21 #define LZMA_INDEX_H 22 23 24 /// Minimum Unpadded Size 25 #define UNPADDED_SIZE_MIN LZMA_VLI_C(5) 26 27 /// Maximum Unpadded Size 28 #define UNPADDED_SIZE_MAX (LZMA_VLI_MAX & ~LZMA_VLI_C(3)) 29 30 /// Index Indicator based on xz specification 31 #define INDEX_INDICATOR 0 32 33 34 /// Get the size of the Index Padding field. This is needed by Index encoder 35 /// and decoder, but applications should have no use for this. 36 extern uint32_t lzma_index_padding_size(const lzma_index *i); 37 38 39 /// Set for how many Records to allocate memory the next time 40 /// lzma_index_append() needs to allocate space for a new Record. 41 /// This is used only by the Index decoder. 42 extern void lzma_index_prealloc(lzma_index *i, lzma_vli records); 43 44 45 /// Round the variable-length integer to the next multiple of four. 46 static inline lzma_vli 47 vli_ceil4(lzma_vli vli) 48 { 49 assert(vli <= UNPADDED_SIZE_MAX); 50 return (vli + 3) & ~LZMA_VLI_C(3); 51 } 52 53 54 /// Calculate the size of the Index field excluding Index Padding 55 static inline lzma_vli 56 index_size_unpadded(lzma_vli count, lzma_vli index_list_size) 57 { 58 // Index Indicator + Number of Records + List of Records + CRC32 59 return 1 + lzma_vli_size(count) + index_list_size + 4; 60 } 61 62 63 /// Calculate the size of the Index field including Index Padding 64 static inline lzma_vli 65 index_size(lzma_vli count, lzma_vli index_list_size) 66 { 67 return vli_ceil4(index_size_unpadded(count, index_list_size)); 68 } 69 70 71 /// Calculate the total size of the Stream 72 static inline lzma_vli 73 index_stream_size(lzma_vli blocks_size, 74 lzma_vli count, lzma_vli index_list_size) 75 { 76 return LZMA_STREAM_HEADER_SIZE + blocks_size 77 + index_size(count, index_list_size) 78 + LZMA_STREAM_HEADER_SIZE; 79 } 80 81 #endif 82