fix(core): remove binparse from cotar reader (#478)

linz · Jul 19, 2023 · 822f646 · 822f646
1 parent 4441843
commit 822f646
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Showing 4 changed files with 31 additions and 21 deletions.
diff --git a/packages/core/src/binary/__test__/binary.header.test.ts b/packages/core/src/binary/__test__/binary.header.test.ts
@@ -1,6 +1,6 @@
 import o from 'ospec';
 import { writeHeaderFooter } from '../binary.index.builder.js';
-import { CotarMetadataParser } from '../binary.index.js';
+import { readMetadata } from '../binary.index.js';
 
 const Example = {
   v1: {
@@ -32,15 +32,13 @@ o.spec('CotarBinaryHeaderFooter', () => {
   });
 
   o('should parse v1 header', () => {
-    const header = CotarMetadataParser.read(Example.v1.buf);
-    o(header.offset).equals(8);
-    o(header.value).deepEquals(Example.v1.header);
+    const header = readMetadata(Example.v1.buf);
+    o(header).deepEquals(Example.v1.header);
   });
 
   o('should parse v2 header', () => {
-    const header = CotarMetadataParser.read(Example.v2.buf);
-    o(header.offset).equals(8);
-    o(header.value).deepEquals(Example.v2.header);
+    const header = readMetadata(Example.v2.buf);
+    o(header).deepEquals(Example.v2.header);
   });
 
   o('should write a header and a footer', () => {
@@ -52,10 +50,10 @@ o.spec('CotarBinaryHeaderFooter', () => {
     o(buf64.startsWith('Q09UAtIClkk')).equals(true);
     o(buf64.endsWith('Q09UAtIClkk=')).equals(true);
 
-    const headStart = CotarMetadataParser.read(buf);
-    const headEnd = CotarMetadataParser.read(buf, buf.length - 8);
+    const headStart = readMetadata(buf);
+    const headEnd = readMetadata(buf.slice(buf.length - 8));
 
-    o(headStart.value).deepEquals(Example.v2.header);
-    o(headEnd.value).deepEquals(Example.v2.header);
+    o(headStart).deepEquals(Example.v2.header);
+    o(headEnd).deepEquals(Example.v2.header);
   });
 });
diff --git a/packages/core/src/binary/binary.index.ts b/packages/core/src/binary/binary.index.ts
@@ -1,18 +1,30 @@
 import { ChunkSource } from '@chunkd/core';
 import fnv1a from '@sindresorhus/fnv1a';
-import { bp } from 'binparse';
 import { CotarIndexRecord } from '../cotar.js';
 import { IndexHeaderSize, IndexMagic, IndexV1RecordSize, IndexV2RecordSize } from './format.js';
 
 const Big0 = BigInt(0);
 const Big32 = BigInt(32);
 const BigUint32Max = BigInt(2 ** 32 - 1);
 
-export const CotarMetadataParser = bp.object('CotarMetadata', {
-  magic: bp.string(IndexMagic.length),
-  version: bp.u8,
-  count: bp.lu32,
-});
+export function readMetadata(bytes: Uint8Array): CotarMetadata {
+  // Read the first three bytes as magic 'COT' string
+  const magic = String.fromCharCode(bytes[0]) + String.fromCharCode(bytes[1]) + String.fromCharCode(bytes[2]);
+
+  // Version number is a uint8
+  const version = bytes[3];
+
+  // Record count from uint32
+  const byteA = bytes[4];
+  const byteB = bytes[5] << 8;
+  const byteC = bytes[6] << 16;
+  const byteD = bytes[7] * 0x1000000;
+  return {
+    magic,
+    version,
+    count: (byteA | byteB | byteC) + byteD,
+  };
+}
 
 export type CotarMetadata = {
   /** Magic string "COT" */
@@ -51,13 +63,13 @@ export class CotarIndex {
     if (isHeader) {
       await source.loadBytes(sourceOffset, source.chunkSize);
       const bytes = source.bytes(sourceOffset, IndexHeaderSize);
-      return CotarMetadataParser.read(bytes).value;
+      return readMetadata(bytes);
     }
 
     // TODO ideally this would a file inside the tar
     // however different tar programs seem to have differing suffixes some have "2x512" bytes of 0 others pad them out further
     const bytes = await source.fetchBytes(-IndexHeaderSize);
-    return CotarMetadataParser.read(new Uint8Array(bytes)).value;
+    return readMetadata(new Uint8Array(bytes));
   }
 
   static async getMetadata(source: ChunkSource, sourceOffset: number, isHeader: boolean): Promise<CotarMetadata> {

diff --git a/packages/core/src/index.ts b/packages/core/src/index.ts
@@ -1,4 +1,4 @@
 export { CotarIndexBuilder, CotarIndexOptions } from './binary/binary.index.builder.js';
 export { CotarIndex as CotarIndexBinary } from './binary/binary.index.js';
 export { Cotar } from './cotar.js';
-export { TarHeader, TarReader } from './tar.js';
+export { TarReader } from './tar.js';
diff --git a/packages/core/src/tar.ts b/packages/core/src/tar.ts
@@ -22,7 +22,7 @@ export enum TarType {
 }
 
 // It takes time to load all the header in, load in only the chunks we care about
-export const TarHeader = bp.object('TarHeader', {
+const TarHeader = bp.static('TarHeader', {
   path: bp.string(100),
   skip1: bp.skip(24),
   // mode: bp.string(8),