Bug 1626815 - Expose startup cache info to about:support. r=froydnj,fluent-reviewers

Adds a new startup cache info service to expose some of the internal
state of the startup cache.

Differential Revision: https://phabricator.services.mozilla.com/D69298

--HG--
extra : moz-landing-system : lando

startupcache/StartupCache.cpp

@@ -137,6 +137,7 @@ nsresult StartupCache::InitSingleton() {
 StaticRefPtr<StartupCache> StartupCache::gStartupCache;
 bool StartupCache::gShutdownInitiated;
 bool StartupCache::gIgnoreDiskCache;
+bool StartupCache::gFoundDiskCacheOnInit;
 
 NS_IMPL_ISUPPORTS(StartupCache, nsIMemoryReporter)
 
@@ -211,6 +212,8 @@ nsresult StartupCache::Init() {
   auto result = LoadArchive();
   rv = result.isErr() ? result.unwrapErr() : NS_OK;
 
+  gFoundDiskCacheOnInit = rv != NS_ERROR_FILE_NOT_FOUND;
+
   // Sometimes we don't have a cache yet, that's ok.
   // If it's corrupted, just remove it and start over.
   if (gIgnoreDiskCache || (NS_FAILED(rv) && rv != NS_ERROR_FILE_NOT_FOUND)) {

startupcache/StartupCache.h

@@ -193,6 +193,8 @@ class StartupCache : public nsIMemoryReporter {
   StartupCache();
   virtual ~StartupCache();
 
+  friend class StartupCacheInfo;
+
   Result<Ok, nsresult> LoadArchive();
   nsresult Init();
 
@@ -238,6 +240,7 @@ class StartupCache : public nsIMemoryReporter {
   static StaticRefPtr<StartupCache> gStartupCache;
   static bool gShutdownInitiated;
   static bool gIgnoreDiskCache;
+  static bool gFoundDiskCacheOnInit;
   PRThread* mWriteThread;
   PRThread* mPrefetchThread;
   UniquePtr<Compression::LZ4FrameDecompressionContext> mDecompressionContext;

startupcache/StartupCacheInfo.cpp

@@ -0,0 +1,47 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "StartupCacheInfo.h"
+
+#include "mozilla/Components.h"
+#include "mozilla/RefPtr.h"
+
+using namespace mozilla;
+using namespace mozilla::scache;
+
+NS_IMPL_ISUPPORTS(StartupCacheInfo, nsIStartupCacheInfo)
+
+nsresult StartupCacheInfo::GetIgnoreDiskCache(bool* aIgnore) {
+  *aIgnore = StartupCache::gIgnoreDiskCache;
+  return NS_OK;
+}
+
+nsresult StartupCacheInfo::GetFoundDiskCacheOnInit(bool* aFound) {
+  *aFound = StartupCache::gFoundDiskCacheOnInit;
+  return NS_OK;
+}
+
+nsresult StartupCacheInfo::GetWroteToDiskCache(bool* aWrote) {
+  if (!StartupCache::gStartupCache) {
+    *aWrote = false;
+  } else {
+    *aWrote = StartupCache::gStartupCache->mWrittenOnce;
+  }
+  return NS_OK;
+}
+
+nsresult StartupCacheInfo::GetDiskCachePath(nsAString& aResult) {
+  if (!StartupCache::gStartupCache || !StartupCache::gStartupCache->mFile) {
+    return NS_OK;
+  }
+  nsAutoString path;
+  StartupCache::gStartupCache->mFile->GetPath(path);
+  aResult.Assign(path);
+  return NS_OK;
+}
+
+NS_IMPL_COMPONENT_FACTORY(nsIStartupCacheInfo) {
+  return MakeAndAddRef<StartupCacheInfo>().downcast<nsISupports>();
+}

startupcache/StartupCacheInfo.h

@@ -0,0 +1,28 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef StartupCacheInfo_h_
+#define StartupCacheInfo_h_
+
+#include "nsIStartupCacheInfo.h"
+
+namespace mozilla {
+namespace scache {
+
+class StartupCacheInfo final : public nsIStartupCacheInfo {
+ public:
+  NS_DECL_ISUPPORTS
+  NS_DECL_NSISTARTUPCACHEINFO
+
+  StartupCacheInfo() = default;
+
+ private:
+  ~StartupCacheInfo() = default;
+};
+
+}  // namespace scache
+}  // namespace mozilla
+
+#endif  // StartupCache_h_

startupcache/components.conf

@@ -0,0 +1,13 @@
+# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*-
+# vim: set filetype=python:
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+Classes = [
+    {
+        'cid': '{a6b2f8b0-7438-11ea-bc55-0242ac130003}',
+        'contract_ids': ['@mozilla.org/startupcacheinfo;1'],
+        'type': 'nsIStartupCacheInfo',
+    },
+]

startupcache/moz.build

@@ -17,7 +17,18 @@ EXPORTS.mozilla.scache += [
 
 UNIFIED_SOURCES += [
     'StartupCache.cpp',
+    'StartupCacheInfo.cpp',
     'StartupCacheUtils.cpp',
 ]
 
+XPCOM_MANIFESTS += [
+    'components.conf',
+]
+
+XPIDL_MODULE = 'startupcache'
+
+XPIDL_SOURCES += [
+    'nsIStartupCacheInfo.idl',
+]
+
 FINAL_LIBRARY = 'xul'

startupcache/nsIStartupCacheInfo.idl

@@ -0,0 +1,38 @@
+/* -*- Mode: IDL; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsISupports.idl"
+
+/* NOTE: this interface is completely undesigned, not stable and likely to change */
+[scriptable, builtinclass, uuid(a6b2f8b0-7438-11ea-bc55-0242ac130003)]
+interface nsIStartupCacheInfo : nsISupports
+{
+  /**
+   * Returns true if the startup cache will not load from the cache from disk.
+   * This can happen if the cache file is corrupt or has been invalidated.
+   */
+  readonly attribute boolean IgnoreDiskCache;
+
+  /**
+   * Returns true if during initialization of the startup cache an existing
+   * cache file was found on disk. This does NOT indicate if the file loaded
+   * successfully.
+   */
+  readonly attribute boolean FoundDiskCacheOnInit;
+
+  /**
+   * Returns true once the current cache file as been written to disk at least
+   * once. If the cache was loaded from disk and never changed this may never
+   * be set to true.
+   */
+  readonly attribute boolean WroteToDiskCache;
+
+  /**
+   * The full path and filename of the startup cache file that will be stored on
+   * disk.
+   */
+  readonly attribute AString DiskCachePath;
+};

toolkit/content/aboutSupport.js

@@ -959,6 +959,14 @@ var snapshotFormatters = {
     }
   },
 
+  startupCache(data) {
+    $("startup-cache-disk-cache-path").textContent = data.DiskCachePath;
+    $("startup-cache-ignore-disk-cache").textContent = data.IgnoreDiskCache;
+    $("startup-cache-found-disk-cache-on-init").textContent =
+      data.FoundDiskCacheOnInit;
+    $("startup-cache-wrote-to-disk-cache").textContent = data.WroteToDiskCache;
+  },
+
   libraryVersions(data) {
     let trs = [
       $.new("tr", [

toolkit/content/aboutSupport.xhtml

@@ -608,6 +608,37 @@
 #endif
 #endif
 
+      <h2 class="major-section" data-l10n-id="startup-cache-title"/>
+
+      <table>
+        <tbody>
+          <tr>
+            <th class="column" data-l10n-id="startup-cache-disk-cache-path"/>
+
+            <td id="startup-cache-disk-cache-path">
+            </td>
+          </tr>
+          <tr>
+            <th class="column" data-l10n-id="startup-cache-ignore-disk-cache"/>
+
+            <td id="startup-cache-ignore-disk-cache">
+            </td>
+          </tr>
+          <tr>
+            <th class="column" data-l10n-id="startup-cache-found-disk-cache-on-init"/>
+
+            <td id="startup-cache-found-disk-cache-on-init">
+            </td>
+          </tr>
+          <tr>
+            <th class="column" data-l10n-id="startup-cache-wrote-to-disk-cache"/>
+
+            <td id="startup-cache-wrote-to-disk-cache">
+            </td>
+          </tr>
+        </tbody>
+      </table>
+
       <h2 class="major-section" data-l10n-id="intl-title"/>
 
       <table>

toolkit/locales/en-US/toolkit/about/aboutSupport.ftl

@@ -300,6 +300,12 @@ sandbox-proc-type-file = file content
 sandbox-proc-type-media-plugin = media plugin
 sandbox-proc-type-data-decoder = data decoder
 
+startup-cache-title = Startup Cache
+startup-cache-disk-cache-path = Disk Cache Path
+startup-cache-ignore-disk-cache = Ignore Disk Cache
+startup-cache-found-disk-cache-on-init = Found Disk Cache on Init
+startup-cache-wrote-to-disk-cache = Wrote to Disk Cache
+
 launcher-process-status-0 = Enabled
 launcher-process-status-1 = Disabled due to failure
 launcher-process-status-2 = Disabled forcibly

toolkit/modules/Troubleshoot.jsm

@@ -714,6 +714,18 @@ var dataProviders = {
     done(data);
   },
 
+  startupCache: function startupCache(done) {
+    const startupInfo = Cc["@mozilla.org/startupcacheinfo;1"].getService(
+      Ci.nsIStartupCacheInfo
+    );
+    done({
+      DiskCachePath: startupInfo.DiskCachePath,
+      IgnoreDiskCache: startupInfo.IgnoreDiskCache,
+      FoundDiskCacheOnInit: startupInfo.FoundDiskCacheOnInit,
+      WroteToDiskCache: startupInfo.WroteToDiskCache,
+    });
+  },
+
   libraryVersions: function libraryVersions(done) {
     let data = {};
     let verInfo = Cc["@mozilla.org/security/nssversion;1"].getService(

toolkit/modules/tests/browser/browser_Troubleshoot.js

@@ -829,6 +829,28 @@ const SNAPSHOT_SCHEMA = {
         },
       },
     },
+    startupCache: {
+      required: false,
+      type: "object",
+      properties: {
+        DiskCachePath: {
+          required: true,
+          type: "string",
+        },
+        IgnoreDiskCache: {
+          required: true,
+          type: "boolean",
+        },
+        FoundDiskCacheOnInit: {
+          required: true,
+          type: "boolean",
+        },
+        WroteToDiskCache: {
+          required: true,
+          type: "boolean",
+        },
+      },
+    },
     intl: {
       required: true,
       type: "object",