refactor: fnv1a52

package.json

@@ -28,7 +28,6 @@
     "crypto-js": "^4.1.1",
     "eslint": "^8.51.0",
     "jsdom": "^22.1.0",
-    "ohash": "^1.1.3",
     "tsup": "^7.2.0",
     "tsx": "^3.13.0",
     "vite": "^4.4.11",

src/fingerprint.ts

@@ -1,5 +1,5 @@
 // eslint-disable-next-line n/no-unpublished-import
-import { murmurHash } from 'ohash'
+import { fnv1a52 } from '~/lib/fnv1a52.ts'
 
 /** {@link https://browserleaks.com/canvas#how-does-it-work} */
 export const getFingerprint = () => {
@@ -25,7 +25,7 @@ export const getFingerprint = () => {
     // TODO: test
     ctx.clearRect(0, 0, canvas.width, canvas.height)
 
-    return murmurHash(fingerprint, 256)
+    return fnv1a52(fingerprint)
   }
   catch {
     return

src/lib/fnv1a52.ts

@@ -0,0 +1,46 @@
+/* eslint-disable tsdoc/syntax */
+/**
+ * FNV-1a Hash implementation
+ * @author Travis Webb (tjwebb) <me@traviswebb.com>
+ *
+ * Ported from https://github.com/tjwebb/fnv-plus/blob/master/index.js
+ *
+ * Simplified, optimized and add modified for 52 bit, which provides a larger hash space
+ * and still making use of Javascript's 53-bit integer space.
+ */
+export const fnv1a52 = (str: string) => {
+  const len = str.length
+  let i = 0,
+    t0 = 0,
+    v0 = 0x23_25,
+    t1 = 0,
+    v1 = 0x84_22,
+    t2 = 0,
+    v2 = 0x9C_E4,
+    t3 = 0,
+    v3 = 0xCB_F2
+
+  while (i < len) {
+    v0 ^= str.codePointAt(i++)!
+    t0 = v0 * 435
+    t1 = v1 * 435
+    t2 = v2 * 435
+    t3 = v3 * 435
+    t2 += v0 << 8
+    t3 += v1 << 8
+    t1 += t0 >>> 16
+    v0 = t0 & 65_535
+    t2 += t1 >>> 16
+    v1 = t1 & 65_535
+    v3 = (t3 + (t2 >>> 16)) & 65_535
+    v2 = t2 & 65_535
+  }
+
+  return (
+    (v3 & 15) * 281_474_976_710_656
+    + v2 * 4_294_967_296
+    + v1 * 65_536
+    + (v0 ^ (v3 >> 4))
+  )
+}
+/* eslint-enable tsdoc/syntax */