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smithy-lang · Jun 5, 2024 · 83ba8b5 · 83ba8b5
1 parent 952394a
commit 83ba8b5
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Showing 8 changed files with 316 additions and 338 deletions.
diff --git a/packages/core/src/submodules/cbor/ByteVector.ts b/packages/core/src/submodules/cbor/ByteVector.ts
@@ -1,5 +1,7 @@
 import { fromUtf8 } from "@smithy/util-utf8";
 
+import { alloc, Uint8 } from "./cbor-types";
+
 const USE_BUFFER = typeof Buffer !== "undefined";
 const USE_TEXT_ENCODER = typeof TextEncoder !== "undefined";
 
@@ -13,70 +15,49 @@ type BufferWithUtf8Write = Buffer & {
  *
  */
 export class ByteVector {
-  private data: Uint8Array = new Uint8Array();
-  private dataView: DataView = new DataView(this.data.buffer, 0, 0);
+  private data: Uint8Array = alloc(0);
+  private dataView: DataView = new DataView(this.data.buffer, this.data.byteOffset, this.data.byteLength);
   private cursor: number = 0;
   private textEncoder: TextEncoder | null = USE_TEXT_ENCODER ? new TextEncoder() : null;
 
   public constructor(private initialSize: number = 1_000_000) {
     this.resize(initialSize);
   }
 
-  public write(...bytes: number[]) {
-    for (const byte of bytes) {
-      if (this.cursor === this.data.length) {
-        this.resize(this.cursor + this.initialSize);
-      }
-      this.data[this.cursor++] = byte;
-    }
+  public write(byte: Uint8) {
+    this.data[this.cursor++] = byte;
   }
 
   public writeBytes(bytes: Uint8Array) {
-    if (this.cursor + bytes.length >= this.data.length) {
-      this.resize(this.cursor + bytes.length + this.initialSize);
-    }
     this.data.set(bytes, this.cursor);
     this.cursor += bytes.byteLength;
   }
 
-  public writeUnsignedInt(major: number, bitSize: 16 | 32 | 64, value: number | bigint) {
-    if (this.cursor + bitSize / 8 >= this.data.length) {
-      this.resize(this.cursor + bitSize / 8 + this.initialSize);
-    }
-    const dv = byteVector.getDataView();
-    switch (bitSize) {
-      case 16:
-        this.write(major);
-        dv.setUint16(byteVector.getCursor(), Number(value) as number);
-        this.cursor += 2;
-        break;
-      case 32:
-        this.write(major);
-        dv.setUint32(byteVector.getCursor(), Number(value) as number);
-        this.cursor += 4;
-        break;
-      case 64:
-        this.write(major);
-        dv.setBigUint64(byteVector.getCursor(), BigInt(value) as bigint);
-        this.cursor += 8;
-        break;
-    }
+  public writeUint16(major: number, value: number) {
+    this.data[this.cursor++] = major;
+    this.data[this.cursor++] = value >> 8;
+    this.data[this.cursor++] = value & 0b1111_1111;
+  }
+
+  public writeUint32(major: number, value: number) {
+    this.data[this.cursor++] = major;
+    this.dataView.setUint32(this.cursor, value as number);
+    this.cursor += 4;
+  }
+
+  public writeUint64(major: number, value: number | bigint) {
+    this.data[this.cursor++] = major;
+    this.dataView.setBigUint64(this.cursor, typeof value === "bigint" ? value : BigInt(value));
+    this.cursor += 8;
   }
 
   public writeFloat64(major: number, value: number) {
-    if (this.cursor + 8 >= this.data.length) {
-      this.resize(this.cursor + 8 + this.initialSize);
-    }
-    const dv = byteVector.getDataView();
-    this.write(major);
-    dv.setFloat64(this.cursor, value);
+    this.data[this.cursor++] = major;
+    this.dataView.setFloat64(this.cursor, value);
     this.cursor += 8;
   }
 
   public writeString(str: string) {
-    if (this.cursor + str.length * 4 > this.data.length) {
-      this.resize(this.cursor + str.length * 4 + this.initialSize);
-    }
     if (USE_BUFFER && (this.data as BufferWithUtf8Write).utf8Write) {
       this.cursor += (this.data as BufferWithUtf8Write).utf8Write(str, this.cursor);
     } else if (USE_TEXT_ENCODER && this.textEncoder?.encodeInto) {
@@ -87,34 +68,31 @@ export class ByteVector {
     }
   }
 
+  public ensureSpace(bytes: number) {
+    if (this.data.byteLength - this.cursor < bytes) {
+      this.resize(this.data.byteLength + this.initialSize + bytes);
+    }
+  }
+
   public toUint8Array(): Uint8Array {
-    const out = new Uint8Array(this.cursor);
+    const out = alloc(this.cursor);
     out.set(this.data.subarray(0, this.cursor), 0);
     this.cursor = 0;
     if (this.data.length > this.initialSize) {
-      this.data = new Uint8Array(this.initialSize);
-      this.dataView = new DataView(this.data.buffer, 0, this.initialSize);
+      this.data = alloc(this.initialSize);
+      this.dataView = new DataView(this.data.buffer, this.data.byteOffset, this.data.byteLength);
     }
     return out;
   }
 
-  public getDataView() {
-    return this.dataView;
-  }
-
-  public getCursor() {
-    return this.cursor;
-  }
-
-  // eslint-disable-next-line @typescript-eslint/no-unused-vars
   private resize(size: number) {
     const data = this.data;
-    this.data = USE_BUFFER ? Buffer.allocUnsafeSlow(size) : new Uint8Array(size);
+    this.data = alloc(size);
     if (data) {
       this.data.set(data, 0);
     }
-    this.dataView = new DataView(this.data.buffer, 0, size);
+    this.dataView = new DataView(this.data.buffer, this.data.byteOffset, this.data.byteLength);
   }
 }
 
-export const byteVector = new ByteVector();
+export const byteVector = new ByteVector(10_000_000);
diff --git a/packages/core/src/submodules/cbor/DecodeView.ts b/packages/core/src/submodules/cbor/DecodeView.ts
@@ -1,13 +1,15 @@
 import { toUtf8 } from "@smithy/util-utf8";
 
+import { alloc } from "./cbor-types";
+
 const USE_TEXT_DECODER = typeof TextDecoder !== "undefined";
 
 /**
  * Data container for synchronous decoding.
  */
 export class DecodeView {
-  public payload = new Uint8Array();
-  public dataView = new DataView(this.payload.buffer, 0, this.payload.length);
+  public payload = alloc(0);
+  public dataView = new DataView(this.payload.buffer, this.payload.byteOffset, this.payload.byteLength);
   private textDecoder = USE_TEXT_DECODER ? new TextDecoder() : null;
 
   public constructor(payload: Uint8Array) {
@@ -16,7 +18,7 @@ export class DecodeView {
 
   public set(payload: Uint8Array) {
     this.payload = payload;
-    this.dataView = new DataView(this.payload.buffer, 0, this.payload.length);
+    this.dataView = new DataView(this.payload.buffer, this.payload.byteOffset, this.payload.byteLength);
   }
 
   public toUtf8(bytes: Uint8Array, at: number, to: number): string {
@@ -27,4 +29,4 @@ export class DecodeView {
   }
 }
 
-export const decodeView = new DecodeView(new Uint8Array());
+export const decodeView = new DecodeView(alloc(0));