feat: Add neapi support

util/zstd.js

@@ -0,0 +1,41 @@
+const zlib = require('zlib')
+const { decompress: fzstdDecompress } = require('fzstd')
+
+// Node 22.15+ 自带 zstd。更早的版本（CI 含 18）用 fzstd 解压，压缩则退回到
+// raw block 帧：内容原样存储，任何 zstd 解码器都能读，只是没有压缩率。
+const hasNative = typeof zlib.zstdCompressSync === 'function'
+
+const MAGIC = Buffer.from([0x28, 0xb5, 0x2f, 0xfd])
+const WINDOW_DESCRIPTOR = 0x50 // windowLog 20
+const BLOCK_MAX = 0x20000 // zstd 单块上限 128 KiB
+
+const compressRawFrame = (input) => {
+  const parts = [MAGIC, Buffer.from([0x00, WINDOW_DESCRIPTOR])]
+  let offset = 0
+  do {
+    const block = input.subarray(offset, offset + BLOCK_MAX)
+    const last = offset + BLOCK_MAX >= input.length
+    const header = Buffer.alloc(3)
+    header.writeUIntLE((block.length << 3) | (last ? 1 : 0), 0, 3)
+    parts.push(header, block)
+    offset += BLOCK_MAX
+  } while (offset < input.length)
+  return Buffer.concat(parts)
+}
+
+const compress = (input) => {
+  const buf = Buffer.isBuffer(input) ? input : Buffer.from(input)
+  return hasNative ? zlib.zstdCompressSync(buf) : compressRawFrame(buf)
+}
+
+const decompress = (input) => {
+  const buf = Buffer.isBuffer(input) ? input : Buffer.from(input)
+  return hasNative
+    ? zlib.zstdDecompressSync(buf)
+    : Buffer.from(fzstdDecompress(buf))
+}
+
+module.exports = {
+  compress,
+  decompress,
+}