fix(trajectory): clean up runtime files across short reads (#109206)

src/trajectory/cleanup.test.ts

@@ -1,7 +1,8 @@
 // Trajectory cleanup tests cover retention pruning of trajectory artifacts.
+import fsSync from "node:fs";
 import fs from "node:fs/promises";
 import path from "node:path";
-import { describe, expect, it } from "vitest";
+import { describe, expect, it, vi } from "vitest";
 import { formatSqliteSessionFileMarker } from "../config/sessions/sqlite-marker.js";
 import { withTempDir } from "../test-helpers/temp-dir.js";
 import {
@@ -131,14 +132,31 @@ describe("trajectory cleanup", () => {
 
       const pointerPath = resolveTrajectoryPointerFilePath(sessionFile);
       await fs.writeFile(pointerPath, pointerFile(sessionId, safeExternalRuntime), "utf8");
-      await removeSessionTrajectoryArtifacts({
-        sessionId,
-        sessionFile,
-        storePath,
-        restrictToStoreDir: true,
-      });
+      const realReadSync = fsSync.readSync.bind(fsSync);
+      let shortReadCalls = 0;
+      const readSpy = vi.spyOn(fsSync, "readSync").mockImplementation(((
+        fd: number,
+        buffer: NodeJS.ArrayBufferView,
+        offset: number,
+        length: number,
+        position: fsSync.ReadPosition | null,
+      ) => {
+        shortReadCalls += 1;
+        return realReadSync(fd, buffer, offset, Math.min(length, 16), position);
+      }) as typeof fsSync.readSync);
+      try {
+        await removeSessionTrajectoryArtifacts({
+          sessionId,
+          sessionFile,
+          storePath,
+          restrictToStoreDir: true,
+        });
+      } finally {
+        readSpy.mockRestore();
+      }
 
       await expectPathMissing(safeExternalRuntime);
+      expect(shortReadCalls).toBeGreaterThan(1);
       await expectPathMissing(pointerPath);
 
       await fs.writeFile(pointerPath, pointerFile(sessionId, unsafeExternalRuntime), "utf8");

src/trajectory/cleanup.ts

@@ -4,6 +4,7 @@ import path from "node:path";
 import { isRecord } from "@openclaw/normalization-core/record-coerce";
 import { resolveSessionFilePath } from "../config/sessions/paths.js";
 import { parseSqliteSessionFileMarker } from "../config/sessions/sqlite-marker.js";
+import { readFileWindowFullySync } from "../infra/file-read.js";
 import { isPathInside } from "../infra/path-guards.js";
 import {
   resolveTrajectoryFilePath,
@@ -79,7 +80,7 @@ function readFirstNonEmptyLine(filePath: string): string | null {
   try {
     fd = fs.openSync(filePath, "r");
     const buffer = Buffer.alloc(64 * 1024);
-    const bytesRead = fs.readSync(fd, buffer, 0, buffer.length, 0);
+    const bytesRead = readFileWindowFullySync(fd, buffer, 0);
     if (bytesRead <= 0) {
       return null;
     }