TheCloud/dwarfs
1
0
Fork 0
mirror of https://github.com/mhx/dwarfs.git synced 2025-09-13 14:27:30 -04:00
Code Issues Packages Projects Releases Wiki Activity

Add constexpr rsync_hash::repeating_window()

Browse Source
This commit is contained in:
Marcus Holland-Moritz 2023-08-18 21:49:49 +02:00
parent db4499847e
commit c903f6b265
1 changed files with 7 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
include/dwarfs/cyclic_hash.h
View File

@ -50,6 +50,13 @@ class rsync_hash {
len_ = 0; len_ = 0;
} }
static constexpr uint32_t repeating_window(uint8_t byte, size_t length) {
uint16_t v = static_cast<uint16_t>(byte);
uint16_t a{static_cast<uint16_t>(v * length)};
uint16_t b{static_cast<uint16_t>(v * (length * (length + 1)) / 2)};
return static_cast<uint32_t>(a) | (static_cast<uint32_t>(b) << 16);
}
private: private:
uint16_t a_{0}; uint16_t a_{0};
uint16_t b_{0}; uint16_t b_{0};