Allow a base address to be added to a file via a URI

media/hexEdit.ts

@@ -33,7 +33,7 @@ function openAnyway(): void {
 					// Loads the html body sent over
 					if (body.html !== undefined) {
 						document.getElementsByTagName("body")[0].innerHTML = body.html;
-						virtualHexDocument = new VirtualDocument(body.fileSize);
+						virtualHexDocument = new VirtualDocument(body.fileSize, body.baseAddress);
 						// We initially load 4 chunks below the viewport (normally we buffer 2 above as well, but there is no above at the start)
 						chunkHandler.ensureBuffer(virtualHexDocument.topOffset(), {
 							topBufferSize: 0,
@@ -80,4 +80,4 @@ function openAnyway(): void {
 
 	// Signal to VS Code that the webview is initialized.
 	messageHandler.postMessage("ready");
-})();
+})();

media/virtualDocument.ts

@@ -22,6 +22,7 @@ export interface VirtualizedPacket {
  */
 export class VirtualDocument {
     private fileSize: number;
+    private baseAddress: number;
     private rowHeight: number;
     public readonly documentHeight: number;
     private viewPortHeight!: number
@@ -37,8 +38,9 @@ export class VirtualDocument {
      * @description Constructs a VirtualDocument for a file of a given size. Also handles the initial DOM layout
      * @param {number} fileSize The size, in bytes, of the file which is being displayed
      */
-    constructor(fileSize: number) {
+    constructor(fileSize: number, baseAddress = 0) {
         this.fileSize = fileSize;
+        this.baseAddress = baseAddress;
         this.editHandler = new EditHandler();
         this.selectHandler = new SelectHandler();
         this.searchHandler = new SearchHandler();
@@ -266,9 +268,10 @@ export class VirtualDocument {
     private populateHexAdresses(fragment: DocumentFragment, rowData: VirtualizedPacket[]): void {
         const offset = rowData[0].offset;
         const addr = document.createElement("div");
+        const displayOffset = offset + this.baseAddress;
         addr.className = "row";
         addr.setAttribute("data-offset", offset.toString());
-        addr.innerText = pad(offset.toString(16), 8).toUpperCase();
+        addr.innerText = pad(displayOffset.toString(16), 8).toUpperCase();
         fragment.appendChild(addr);
         this.rows[0].set(offset.toString(), addr);
         // We add a left px offset to effectively right align the column

src/hexDocument.ts

@@ -2,6 +2,7 @@
 // Licensed under the MIT license.
 
 import * as vscode from "vscode";
+import * as fs from "fs";
 import { Disposable } from "./dispose";
 import TelemetryReporter from "vscode-extension-telemetry";
 import { SearchProvider } from "./searchProvider";
@@ -43,6 +44,8 @@ export class HexDocument extends Disposable implements vscode.CustomDocument {
 		const dataFile = typeof backupId === "string" ? vscode.Uri.parse(backupId) : uri;
 		const unsavedEditURI = typeof backupId === "string" ? vscode.Uri.parse(backupId + ".json") : undefined;
 		const fileSize = (await vscode.workspace.fs.stat(dataFile)).size;
+		const queries = HexDocument.parseQuery(uri.query);
+		const baseAddress: number = queries["baseAddress"] ? HexDocument.parseHexOrDecInt(queries["baseAddress"]) : 0;
 		/* __GDPR__
 			"fileOpen" : {
 				"fileSize" : { "classification": "SystemMetaData", "purpose": "FeatureInsight", "isMeasurement": true },
@@ -62,13 +65,13 @@ export class HexDocument extends Disposable implements vscode.CustomDocument {
 				unsavedEdits = JSON.parse(Buffer.from(jsonData).toString("utf-8"));
 			}
 		}
-		return new HexDocument(uri, fileData, fileSize, unsavedEdits);
+		return new HexDocument(uri, fileData, fileSize, unsavedEdits, baseAddress);
 	}
 
 	private readonly _uri: vscode.Uri;
 
 	private _bytesize: number;
-
+	private _baseAddress: number;
 	private _documentData: Uint8Array;
 
 	private _edits: HexDocumentEdit[][] = [];
@@ -83,12 +86,14 @@ export class HexDocument extends Disposable implements vscode.CustomDocument {
 		uri: vscode.Uri,
 		initialContent: Uint8Array,
 		fileSize: number,
-		unsavedEdits: HexDocumentEdit[][]
+		unsavedEdits: HexDocumentEdit[][],
+		baseAddress: number
 	) {
 		super();
 		this._uri = uri;
 		this._documentData = initialContent;
 		this._bytesize = fileSize;
+		this._baseAddress = baseAddress;
 		this._unsavedEdits = unsavedEdits;
 		// If we don't do this Array.from casting then both will reference the same array causing bad behavior
 		this._edits = Array.from(unsavedEdits);
@@ -110,6 +115,7 @@ export class HexDocument extends Disposable implements vscode.CustomDocument {
 		return this._bytesize + numAdditions;
 	}
 
+	public get baseAddress(): number { return this._baseAddress; }
 	public get documentData(): Uint8Array { return this._documentData; }
 
 	/**
@@ -160,6 +166,7 @@ export class HexDocument extends Disposable implements vscode.CustomDocument {
 
 	private readonly _onDidChangeDocument = this._register(new vscode.EventEmitter<{
 		readonly fileSize: number;
+		readonly baseAddress: number;
 		readonly type: "redo" | "undo" | "revert";
 		readonly edits: readonly HexDocumentEdit[];
 	}>());
@@ -218,6 +225,7 @@ export class HexDocument extends Disposable implements vscode.CustomDocument {
 				if (unsavedEdits.length !== 0)	this._unsavedEdits.push(unsavedEdits);
 				this._onDidChangeDocument.fire({
 					fileSize: this.filesize,
+					baseAddress: this.baseAddress,
 					type: "undo",
 					edits: undoneEdits,
 				});
@@ -248,6 +256,7 @@ export class HexDocument extends Disposable implements vscode.CustomDocument {
 				if (unsavedEdits.length !== 0) this._unsavedEdits.push(unsavedEdits);
 				this._onDidChangeDocument.fire({
 					fileSize: this.filesize,
+					baseAddress: this.baseAddress,
 					type: "redo",
 					edits: redoneEdits
 				});
@@ -291,6 +300,7 @@ export class HexDocument extends Disposable implements vscode.CustomDocument {
 		// this._edits.flat().forEach(e => e.sameOnDisk = true);
 		this._onDidChangeDocument.fire({
 			fileSize: this.filesize,
+			baseAddress: this.baseAddress,
 			type: "revert",
 			edits: []
 		});
@@ -362,4 +372,31 @@ export class HexDocument extends Disposable implements vscode.CustomDocument {
 		if (allEdits.length !== 0) this.makeEdit(allEdits);
 		return allEdits;
 	}
+
+
+	/**
+	 * Utility function to convert a Uri query string into a map
+	 */
+	private static parseQuery(queryString: string): { [key: string]: string } {
+		const queries: { [key: string]: string } = {};
+		if (queryString) {
+			const pairs = (queryString[0] === "?" ? queryString.substr(1) : queryString).split("&");
+			for (const q of pairs) {
+				const pair = q.split("=");
+				const name = pair.shift();
+				if (name) {
+					queries[name] = pair.join("=");
+				}
+			}
+		}
+		return queries;
+	}
+
+	/**
+	 * Utility function to parse a number. Only hex and decimal supported
+	 */
+	private static parseHexOrDecInt(str: string): number {
+		str = str.toLowerCase();
+		return str.startsWith("0x") ? parseInt(str.substring(2), 16) : parseInt(str, 10);
+	}
 }

src/hexEditorProvider.ts

@@ -2,6 +2,7 @@
 // Licensed under the MIT license.
 
 import * as vscode from "vscode";
+import * as fs from "fs";
 import { HexDocument, HexDocumentEdit } from "./hexDocument";
 import { disposeAll } from "./dispose";
 import { WebviewCollection } from "./webViewCollection";
@@ -57,6 +58,7 @@ export class HexEditorProvider implements vscode.CustomEditorProvider<HexDocumen
 			for (const webviewPanel of this.webviews.get(document.uri)) {
 				this.postMessage(webviewPanel, "update", {
 					fileSize: e.fileSize,
+					baseAddress: e.baseAddress,
 					type: e.type,
 					edits: e.edits
 				});
@@ -124,6 +126,7 @@ export class HexEditorProvider implements vscode.CustomEditorProvider<HexDocumen
 			if (e.type === "ready") {
 				this.postMessage(webviewPanel, "init", {
 					fileSize: document.filesize,
+					baseAddress: document.baseAddress,
 					html: document.documentData.length === document.filesize || document.unsavedEdits.length != 0 ? this.getBodyHTML() : undefined
 				});
 			}
@@ -134,6 +137,7 @@ export class HexEditorProvider implements vscode.CustomEditorProvider<HexDocumen
 				await document.openAnyways();
 				this.postMessage(webviewPanel, "init", {
 					fileSize: document.filesize,
+					baseAddress: document.baseAddress,
 					html: this.getBodyHTML()
 				});
 			}
@@ -422,6 +426,7 @@ export class HexEditorProvider implements vscode.CustomEditorProvider<HexDocumen
 				});
 				panel.webview.postMessage({ type: "packet", requestId: message.requestId, body: {
 					fileSize: document.filesize,
+					baseAddress: document.baseAddress,
 					data: packet,
 					offset: request.initialOffset,
 					edits: edits
@@ -431,7 +436,8 @@ export class HexEditorProvider implements vscode.CustomEditorProvider<HexDocumen
 				document.makeEdit(message.body);
 				// We respond with the size of the file so that the webview is always in sync with the ext host
 				panel.webview.postMessage({ type: "edit", requestId: message.requestId, body: {
-					fileSize: document.filesize
+					fileSize: document.filesize,
+					baseAddress: document.baseAddress,
 				} });
 				return;
 			case "search":