Follow pointers (#122)

Add command to go to value of a variable.
eclipse-cdt-cloud · May 6, 2024 · 36db026 · 36db026
1 parent 835ef75
commit 36db026
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Showing 7 changed files with 67 additions and 8 deletions.
diff --git a/package.json b/package.json
@@ -85,6 +85,11 @@
         "title": "Show in Memory Inspector",
         "category": "Memory"
       },
+      {
+        "command": "memory-inspector.go-to-value",
+        "title": "Go to value in Memory Inspector",
+        "category": "Memory"
+      },
       {
         "command": "memory-inspector.toggle-variables-column",
         "title": "Toggle Variables Column",
@@ -144,6 +149,10 @@
           "command": "memory-inspector.show-variable",
           "when": "canViewMemory && memory-inspector.canRead"
         },
+        {
+          "command": "memory-inspector.go-to-value",
+          "when": "canViewMemory && memory-inspector.canRead && memory-inspector.variable.isPointer"
+        },
         {
           "command": "memory-inspector.store-file",
           "when": "canViewMemory && memory-inspector.canRead"
@@ -199,6 +208,11 @@
           "command": "memory-inspector.show-advanced-display-options",
           "group": "z_more",
           "when": "webviewId === memory-inspector.memory"
+        },
+        {
+          "command": "memory-inspector.go-to-value",
+          "group": "display@7",
+          "when": "webviewId === memory-inspector.memory && memory-inspector.variable.isPointer"
         }
       ]
     },

diff --git a/src/common/debug-requests.ts b/src/common/debug-requests.ts
@@ -29,7 +29,8 @@ export interface DebugRequestTypes {
 
 export interface DebugEvents {
     'memory': DebugProtocol.MemoryEvent,
-    'stopped': DebugProtocol.StoppedEvent
+    'stopped': DebugProtocol.StoppedEvent,
+    'output': DebugProtocol.OutputEvent,
 }
 
 export type DebugRequest<C, A> = Omit<DebugProtocol.Request, 'command' | 'arguments'> & { command: C, arguments: A };

diff --git a/src/common/memory-range.ts b/src/common/memory-range.ts
@@ -108,6 +108,7 @@ export interface VariableMetadata {
     type?: string;
     /** If applicable, a string representation of the variable's value */
     value?: string;
+    isPointer?: boolean;
 }
 
 /** Suitable for transmission as JSON */

diff --git a/src/common/webview-context.ts b/src/common/webview-context.ts
@@ -58,3 +58,13 @@ export function isWebviewContext(args: WebviewContext | unknown): args is Webvie
         && typeof assumed.showRadixPrefix === 'boolean' && typeof assumed.activeReadArguments?.count === 'number' && typeof assumed.activeReadArguments?.offset === 'number'
         && typeof assumed.activeReadArguments?.memoryReference === 'string';
 }
+
+export function isWebviewVariableContext(args: WebviewVariableContext | unknown): args is Required<WebviewVariableContext> {
+    const assumed = args ? args as WebviewVariableContext : undefined;
+    return !!assumed && isWebviewContext(args)
+        && !!assumed.variable
+        && typeof assumed.variable.name === 'string' && !!assumed.variable.name
+        && (typeof assumed.variable.type === 'string' || assumed.variable.type === undefined)
+        && (typeof assumed.variable.value === 'string' || assumed.variable.value === undefined)
+        && (typeof assumed.variable.isPointer === 'boolean' || assumed.variable.isPointer === undefined);
+}
diff --git a/src/plugin/adapter-registry/c-tracker.ts b/src/plugin/adapter-registry/c-tracker.ts
@@ -18,7 +18,7 @@ import { DebugProtocol } from '@vscode/debugprotocol';
 import * as vscode from 'vscode';
 import { sendRequest } from '../../common/debug-requests';
 import { toHexStringWithRadixMarker, VariableRange } from '../../common/memory-range';
-import { AdapterVariableTracker, extractAddress, notADigit } from './adapter-capabilities';
+import { AdapterVariableTracker, decimalAddress, extractAddress, hexAddress, notADigit } from './adapter-capabilities';
 
 export namespace CEvaluateExpression {
     export function sizeOf(expression: string): string {
@@ -47,7 +47,7 @@ export class CTracker extends AdapterVariableTracker {
             const evaluateName = variable.evaluateName ?? variable.name;
             [variableAddress, variableSize] = await Promise.all([
                 variableAddress ?? this.getAddressOfVariable(evaluateName, session),
-                this.getSizeOfVariable(evaluateName, session)
+                this.getSizeOfVariable(evaluateName, session),
             ]);
         } catch (err) {
             this.logger.warn('Unable to resolve location and size of', variable.name + (err instanceof Error ? ':\n\t' + err.message : ''));
@@ -58,12 +58,15 @@ export class CTracker extends AdapterVariableTracker {
         }
         this.logger.debug('Resolved', variable.name, { start: variableAddress, size: variableSize });
         const address = BigInt(variableAddress);
+        const startAddress = toHexStringWithRadixMarker(address);
+        const isPointer = this.isMaybePointer(variable, startAddress);
         const variableRange: VariableRange = {
             name: variable.name,
-            startAddress: toHexStringWithRadixMarker(address),
+            startAddress,
             endAddress: variableSize === undefined ? undefined : toHexStringWithRadixMarker(address + variableSize),
             value: variable.value,
             type: variable.type,
+            isPointer,
         };
         return variableRange;
     }
@@ -77,4 +80,11 @@ export class CTracker extends AdapterVariableTracker {
         const response = await sendRequest(session, 'evaluate', { expression: CEvaluateExpression.sizeOf(variableName), context: 'watch', frameId: this.currentFrame });
         return notADigit.test(response.result) ? undefined : BigInt(response.result);
     }
+
+    protected isMaybePointer({ value, type }: DebugProtocol.Variable, startAddress: string): boolean {
+        if (type?.endsWith('*')) { return true; } // Definitely a pointer
+
+        // Might reasonably get cast as a pointer
+        return (value !== startAddress) && (hexAddress.test(value) || decimalAddress.test(value));
+    }
 }
diff --git a/src/plugin/memory-webview-main.ts b/src/plugin/memory-webview-main.ts
@@ -43,7 +43,7 @@ import {
     WriteMemoryResult,
     writeMemoryType,
 } from '../common/messaging';
-import { getVisibleColumns, WebviewContext } from '../common/webview-context';
+import { getVisibleColumns, isWebviewVariableContext, WebviewContext } from '../common/webview-context';
 import { AddressPaddingOptions, MemoryViewSettings, ScrollingBehavior } from '../webview/utils/view-types';
 import { isVariablesContext } from './external-views';
 import { outputChannelLogger } from './logger';
@@ -65,6 +65,7 @@ export class MemoryWebview implements vscode.CustomReadonlyEditorProvider {
     public static ViewType = `${manifest.PACKAGE_NAME}.memory`;
     public static ShowCommandType = `${manifest.PACKAGE_NAME}.show`;
     public static VariableCommandType = `${manifest.PACKAGE_NAME}.show-variable`;
+    public static GoToValueCommandType = `${manifest.PACKAGE_NAME}.go-to-value`;
     public static ToggleAsciiColumnCommandType = `${manifest.PACKAGE_NAME}.toggle-ascii-column`;
     public static ToggleVariablesColumnCommandType = `${manifest.PACKAGE_NAME}.toggle-variables-column`;
     public static ToggleRadixPrefixCommandType = `${manifest.PACKAGE_NAME}.toggle-radix-prefix`;
@@ -97,6 +98,11 @@ export class MemoryWebview implements vscode.CustomReadonlyEditorProvider {
                     this.show({ memoryReference });
                 }
             }),
+            vscode.commands.registerCommand(MemoryWebview.GoToValueCommandType, async args => {
+                if (isWebviewVariableContext(args) && args.variable.isPointer) {
+                    this.show({ memoryReference: args.variable.value });
+                }
+            }),
             vscode.commands.registerCommand(MemoryWebview.ToggleVariablesColumnCommandType, (ctx: WebviewContext) => {
                 this.toggleWebviewColumn(ctx, 'variables');
             }),

diff --git a/src/webview/utils/vscode-contexts.ts b/src/webview/utils/vscode-contexts.ts
@@ -28,7 +28,24 @@ export interface VscodeContext {
 export type WebviewSection = 'optionsWidget' | 'advancedOptionsOverlay' | 'memoryTable';
 
 export function createVscodeContext<C extends {}>(context: C): VscodeContext {
-    return { 'data-vscode-context': JSON.stringify(context) };
+    return { 'data-vscode-context': JSON.stringify(includeFlatKeys(context)) };
+}
+
+function includeFlatKeys(src: object): Record<string, unknown> {
+    return { ...src, ...flattenKeys(src) };
+}
+
+// VSCode context cannot make use of nested keys in 'when' clauses.
+function flattenKeys(src: object, dst: Record<string, unknown> = {}, prefix = 'memory-inspector.'): Record<string, unknown> {
+    if (!src || typeof src !== 'object') { return dst; }
+    for (const [key, value] of Object.entries(src)) {
+        if (value && typeof value === 'object' && !Array.isArray(value)) {
+            flattenKeys(value, dst, `${prefix}${key}.`);
+        } else {
+            dst[`${prefix}${key}`] = value;
+        }
+    }
+    return dst;
 }
 
 export function createSectionVscodeContext(webviewSection: WebviewSection): VscodeContext {
@@ -44,7 +61,7 @@ export function createAppVscodeContext(context: Omit<WebviewContext, 'webviewSec
 }
 
 export function createVariableVscodeContext(variable: BigIntVariableRange): VscodeContext {
-    const { name, type, value } = variable;
-    return createVscodeContext({ variable: { name, type, value } });
+    const { name, type, value, isPointer } = variable;
+    return createVscodeContext({ variable: { name, type, value, isPointer } });
 }