platform: combine remaining POSIX, runtime, and SQLite fixes

apps/browser-demos/lib/init/index.ts

@@ -23,6 +23,3 @@ export { COREUTILS_NAMES } from "./shell-binaries";
 
 // Service worker bridge
 export { initServiceWorkerBridge } from "./service-worker-bridge";
-
-// MariaDB directory setup
-export { populateMariadbDirs } from "./mariadb-config";

apps/browser-demos/lib/kernel-owned-boot.ts

@@ -9,9 +9,12 @@
 // left is the small, transient per-boot image-build FS; these helpers track it
 // and nudge WebKit's collector to reclaim it between boots.
 import { MemoryFileSystem } from "@host/vfs/memory-fs";
+import { overlayEtcFromRootfs } from "@host/vfs/rootfs-overlay";
 // @ts-expect-error — vite ?url virtual module (resolved by the kernel-artifacts plugin)
 import rootfsVfsUrl from "@rootfs-vfs?url";
 
+export { overlayEtcFromRootfs };
+
 const WEBKIT_RECLAIM_TIMEOUT_MS = 1_500;
 const WEBKIT_RECLAIM_STEP_MS = 150;
 const WEBKIT_RECLAIM_PRESSURE_BYTES = 32 * 1024 * 1024;
@@ -91,116 +94,6 @@ export function createEmptyBuildFs(maxByteLength = 64 * 1024 * 1024): MemoryFile
   return MemoryFileSystem.create(sab, maxByteLength);
 }
 
-const S_IFMT = 0xf000;
-const S_IFREG = 0x8000;
-const S_IFDIR = 0x4000;
-const S_IFLNK = 0xa000;
-
-function copyMissingRootfsPath(
-  source: MemoryFileSystem,
-  target: MemoryFileSystem,
-  path: string,
-): void {
-  const sourceStat = source.lstat(path);
-  const sourceKind = sourceStat.mode & S_IFMT;
-  let targetKind: number | null = null;
-  try {
-    targetKind = target.lstat(path).mode & S_IFMT;
-  } catch {
-    // Missing in the caller's image: copy it from the canonical rootfs.
-  }
-
-  // Existing caller-owned leaves always win. Existing directories merge with
-  // canonical directories so a demo can override one file without losing the
-  // rest of that subtree.
-  if (targetKind !== null && (sourceKind !== S_IFDIR || targetKind !== S_IFDIR)) {
-    return;
-  }
-
-  if (sourceKind === S_IFDIR) {
-    if (targetKind === null) {
-      target.mkdirWithOwner(
-        path,
-        sourceStat.mode & 0o7777,
-        sourceStat.uid,
-        sourceStat.gid,
-      );
-    }
-    const dh = source.opendir(path);
-    try {
-      for (;;) {
-        const entry = source.readdir(dh);
-        if (entry === null) break;
-        if (entry.name === "." || entry.name === "..") continue;
-        copyMissingRootfsPath(
-          source,
-          target,
-          path === "/" ? `/${entry.name}` : `${path}/${entry.name}`,
-        );
-      }
-    } finally {
-      source.closedir(dh);
-    }
-    return;
-  }
-
-  if (sourceKind === S_IFLNK) {
-    target.symlinkWithOwner(
-      source.readlink(path),
-      path,
-      sourceStat.uid,
-      sourceStat.gid,
-    );
-    return;
-  }
-
-  if (sourceKind !== S_IFREG) {
-    throw new Error(`Unsupported canonical /etc file type at ${path}`);
-  }
-
-  const bytes = new Uint8Array(sourceStat.size);
-  const fd = source.open(path, 0, 0);
-  let offset = 0;
-  try {
-    while (offset < bytes.length) {
-      const count = source.read(
-        fd,
-        bytes.subarray(offset),
-        null,
-        bytes.length - offset,
-      );
-      if (count <= 0) {
-        throw new Error(
-          `Short read while copying canonical rootfs path ${path}: ` +
-            `${offset}/${bytes.length} bytes`,
-        );
-      }
-      offset += count;
-    }
-  } finally {
-    source.close(fd);
-  }
-  target.createFileWithOwner(
-    path,
-    sourceStat.mode & 0o7777,
-    sourceStat.uid,
-    sourceStat.gid,
-    bytes,
-  );
-}
-
-/**
- * Recursively merge canonical `/etc` state into `target`, without overwriting
- * files or symlinks the caller already wrote. This replaces the legacy
- * worker-side `/etc` overlay that `kernel.init()` performed: demos that start
- * from a small custom image still inherit rootfs-owned account, resolver, TLS,
- * and other configuration through the normal VFS path.
- */
-export function overlayEtcFromRootfs(target: MemoryFileSystem, rootfsImage: Uint8Array): void {
-  const source = MemoryFileSystem.fromImage(rootfsImage);
-  copyMissingRootfsPath(source, target, "/etc");
-}
-
 /**
  * Convenience: an empty build FS pre-seeded with `/etc` from the canonical
  * rootfs — the kernel-owned equivalent of the legacy empty-FS + init()-overlay

apps/browser-demos/pages/network/network-demo-worker.ts

@@ -1,4 +1,5 @@
 import { CAPTURED_STDIO, CentralizedKernelWorker } from "@host/kernel-worker";
+import { installBrowserSetImmediatePolyfill } from "@host/browser-immediate-polyfill";
 import { BrowserWorkerAdapter } from "@host/worker-adapter-browser";
 import { detectPtrWidth, extractHeapBase } from "@host/constants";
 import { LocalVirtualNetwork } from "@host/networking/virtual-network";
@@ -16,43 +17,7 @@ import workerEntryUrl from "@host/worker-entry-browser.ts?worker&url";
 import ncWasmUrl from "@binaries/programs/wasm32/nc.wasm?url";
 import curlWasmUrl from "@binaries/programs/wasm32/curl.wasm?url";
 
-if (typeof (globalThis as typeof globalThis & { setImmediate?: unknown }).setImmediate === "undefined") {
-  const queue: Array<{ id: number; fn: (...args: unknown[]) => void; args: unknown[] }> = [];
-  const cancelled = new Set<number>();
-  const channel = new MessageChannel();
-  let nextId = 0;
-  let scheduled = false;
-  let flushing = false;
-
-  channel.port1.onmessage = () => {
-    scheduled = false;
-    flushing = true;
-    const count = queue.length;
-    for (let i = 0; i < count && queue.length > 0; i++) {
-      const entry = queue.shift()!;
-      if (cancelled.delete(entry.id)) continue;
-      entry.fn(...entry.args);
-    }
-    flushing = false;
-    if (queue.length > 0 && !scheduled) {
-      scheduled = true;
-      channel.port2.postMessage(null);
-    }
-  };
-
-  (globalThis as typeof globalThis & { setImmediate: (fn: (...args: unknown[]) => void, ...args: unknown[]) => number }).setImmediate =
-    (fn, ...args) => {
-      const id = ++nextId;
-      queue.push({ id, fn, args });
-      if (!scheduled && !flushing) {
-        scheduled = true;
-        channel.port2.postMessage(null);
-      }
-      return id;
-    };
-  (globalThis as typeof globalThis & { clearImmediate: (id: number) => void }).clearImmediate =
-    (id) => { cancelled.add(id); };
-}
+installBrowserSetImmediatePolyfill();
 
 const MAX_PAGES = 16384;
 const CH_TOTAL_SIZE = 72 + 65536;

apps/browser-demos/pages/sqlite-test/main.ts

@@ -7,6 +7,10 @@ import { BrowserKernel } from "@host/browser-kernel-host";
 import { MemoryFileSystem } from "@host/vfs/memory-fs";
 import { writeVfsFile } from "@host/vfs/image-helpers";
 import { finalizeKernelOwnedImage, settleWebKitReclaim } from "../../lib/kernel-owned-boot";
+import {
+  patchTestrunnerForKandelo,
+  testrunnerPlatformShim,
+} from "./testrunner-patch";
 import kernelWasmUrl from "@kernel-wasm?url";
 
 declare global {
@@ -91,6 +95,20 @@ async function collectArtifactsFromKernel(
   return artifacts.length > 0 ? artifacts : undefined;
 }
 
+function installTestrunnerPatches(fs: MemoryFileSystem): void {
+  const runnerPath = "/sqlite/test/testrunner.tcl";
+  const decoder = new TextDecoder();
+  const runner = decoder.decode(readVfsFile(fs, runnerPath));
+  writeVfsFile(fs, runnerPath, patchTestrunnerForKandelo(runner), 0o644);
+
+  writeVfsFile(fs, "/sqlite/kandelo-testrunner.tcl", [
+    testrunnerPlatformShim,
+    "set argv0 test/testrunner.tcl",
+    "source $argv0",
+    "",
+  ].join("\n"), 0o644);
+}
+
 function createFs(): MemoryFileSystem {
   if (!vfsImageBytes) throw new Error("SQLite test VFS image not loaded");
   const fs = MemoryFileSystem.fromImage(vfsImageBytes, {
@@ -153,13 +171,7 @@ async function init() {
     // SharedArrayBuffer across the per-test loop (Safari OOM fix).
     const buildFs = createFs();
     if (argv[1] === "kandelo-testrunner.tcl") {
-      writeVfsFile(buildFs, "/sqlite/kandelo-testrunner.tcl", [
-        "set ::tcl_platform(os) OpenBSD",
-        "set ::tcl_platform(platform) unix",
-        "set argv0 test/testrunner.tcl",
-        "source $argv0",
-        "",
-      ].join("\n"), 0o644);
+      installTestrunnerPatches(buildFs);
     }
     const vfsImage = await finalizeKernelOwnedImage(buildFs);
     const kernel = new BrowserKernel({