Module: Oselvar::Var::Core::Hash32

Defined in:
lib/oselvar/var/core/hash.rb

Overview

FNV-1a (32-bit) change-detector over UTF-16 code units. Not a security hash: tiny and byte-identical to the TS/Python/JVM ports so var.lock.json fingerprints match everywhere. The "fnv1a:" prefix namespaces the algorithm. Port of hash.ts.

Constant Summary collapse

FNV_OFFSET = 
0x811c9dc5
FNV_PRIME = 
0x01000193
MASK = 
0xffffffff

Class Method Summary collapse

Class Method Details

.hash_source(source) ⇒ Object 



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# File 'lib/oselvar/var/core/hash.rb', line 17

def hash_source(source)
  h = FNV_OFFSET
  data = source.encode('UTF-16LE').bytes
  (0...data.length).step(2) do |i|
    unit = data[i] | (data[i + 1] << 8)
    h = ((h ^ unit) * FNV_PRIME) & MASK
  end
  format('fnv1a:%08x', h)
end