Adding upstream version 115.8.0esr.upstream/115.8.0esr

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 551 insertions, 0 deletions

diff --git a/modules/libpref/Preferences.h b/modules/libpref/Preferences.h
new file mode 100644
index 0000000000..7540755422
--- /dev/null
+++ b/modules/libpref/Preferences.h
@@ -0,0 +1,551 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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/. */
+
+// Documentation for libpref is in modules/libpref/docs/index.rst.
+
+#ifndef mozilla_Preferences_h
+#define mozilla_Preferences_h
+
+#ifndef MOZILLA_INTERNAL_API
+#  error "This header is only usable from within libxul (MOZILLA_INTERNAL_API)."
+#endif
+
+#include "mozilla/Atomics.h"
+#include "mozilla/MemoryReporting.h"
+#include "mozilla/StaticPtr.h"
+#include "nsCOMPtr.h"
+#include "nsIObserver.h"
+#include "nsIPrefBranch.h"
+#include "nsIPrefService.h"
+#include "nsString.h"
+#include "nsTArray.h"
+#include "nsWeakReference.h"
+#include "nsXULAppAPI.h"
+#include <atomic>
+#include <functional>
+
+class nsIFile;
+
+// The callback function will get passed the pref name which triggered the call
+// and the void* data which was passed to the registered callback function.
+typedef void (*PrefChangedFunc)(const char* aPref, void* aData);
+
+class nsPrefBranch;
+
+namespace mozilla {
+
+struct RegisterCallbacksInternal;
+
+void UnloadPrefsModule();
+
+class PreferenceServiceReporter;
+
+namespace dom {
+class Pref;
+class PrefValue;
+}  // namespace dom
+
+namespace ipc {
+class FileDescriptor;
+}  // namespace ipc
+
+struct PrefsSizes;
+
+// Xlib.h defines Bool as a macro constant. Don't try to define this enum if
+// it's already been included.
+#ifndef Bool
+
+// Keep this in sync with PrefType in parser/src/lib.rs.
+enum class PrefType : uint8_t {
+  None = 0,  // only used when neither the default nor user value is set
+  String = 1,
+  Int = 2,
+  Bool = 3,
+};
+
+#endif
+
+#ifdef XP_UNIX
+// We need to send two shared memory descriptors to every child process:
+//
+// 1) A read-only/write-protected snapshot of the initial state of the
+//    preference database. This memory is shared between all processes, and
+//    therefore cannot be modified once it has been created.
+//
+// 2) A set of changes on top of the snapshot, containing the current values of
+//    all preferences which have changed since it was created.
+//
+// Since the second set will be different for every process, and the first set
+// cannot be modified, it is unfortunately not possible to combine them into a
+// single file descriptor.
+//
+// XXX: bug 1440207 is about improving how fixed fds such as this are used.
+static const int kPrefsFileDescriptor = 8;
+static const int kPrefMapFileDescriptor = 9;
+#endif
+
+// Keep this in sync with PrefType in parser/src/lib.rs.
+enum class PrefValueKind : uint8_t { Default, User };
+
+class Preferences final : public nsIPrefService,
+                          public nsIObserver,
+                          public nsIPrefBranch,
+                          public nsSupportsWeakReference {
+  friend class ::nsPrefBranch;
+
+ public:
+  NS_DECL_THREADSAFE_ISUPPORTS
+  NS_DECL_NSIPREFSERVICE
+  NS_FORWARD_NSIPREFBRANCH(mRootBranch->)
+  NS_DECL_NSIOBSERVER
+
+  Preferences();
+
+  // Returns true if the Preferences service is available, false otherwise.
+  static bool IsServiceAvailable();
+
+  // Initialize user prefs from prefs.js/user.js
+  static void InitializeUserPrefs();
+  static void FinishInitializingUserPrefs();
+
+  // Returns the singleton instance which is addreffed.
+  static already_AddRefed<Preferences> GetInstanceForService();
+
+  // Finallizes global members.
+  static void Shutdown();
+
+  // Returns shared pref service instance NOTE: not addreffed.
+  static nsIPrefService* GetService() {
+    NS_ENSURE_TRUE(InitStaticMembers(), nullptr);
+    return sPreferences;
+  }
+
+  // Returns shared pref branch instance. NOTE: not addreffed.
+  static nsIPrefBranch* GetRootBranch(
+      PrefValueKind aKind = PrefValueKind::User) {
+    NS_ENSURE_TRUE(InitStaticMembers(), nullptr);
+    return (aKind == PrefValueKind::Default) ? sPreferences->mDefaultRootBranch
+                                             : sPreferences->mRootBranch;
+  }
+
+  // Gets the type of the pref.
+  static int32_t GetType(const char* aPrefName);
+
+  // Fallible value getters. When `aKind` is `User` they will get the user
+  // value if possible, and fall back to the default value otherwise.
+  static nsresult GetBool(const char* aPrefName, bool* aResult,
+                          PrefValueKind aKind = PrefValueKind::User);
+  static nsresult GetInt(const char* aPrefName, int32_t* aResult,
+                         PrefValueKind aKind = PrefValueKind::User);
+  static nsresult GetUint(const char* aPrefName, uint32_t* aResult,
+                          PrefValueKind aKind = PrefValueKind::User) {
+    return GetInt(aPrefName, reinterpret_cast<int32_t*>(aResult), aKind);
+  }
+  static nsresult GetFloat(const char* aPrefName, float* aResult,
+                           PrefValueKind aKind = PrefValueKind::User);
+  static nsresult GetCString(const char* aPrefName, nsACString& aResult,
+                             PrefValueKind aKind = PrefValueKind::User);
+  static nsresult GetString(const char* aPrefName, nsAString& aResult,
+                            PrefValueKind aKind = PrefValueKind::User);
+  static nsresult GetLocalizedCString(
+      const char* aPrefName, nsACString& aResult,
+      PrefValueKind aKind = PrefValueKind::User);
+  static nsresult GetLocalizedString(const char* aPrefName, nsAString& aResult,
+                                     PrefValueKind aKind = PrefValueKind::User);
+  static nsresult GetComplex(const char* aPrefName, const nsIID& aType,
+                             void** aResult,
+                             PrefValueKind aKind = PrefValueKind::User);
+
+  // Infallible getters of user or default values, with fallback results on
+  // failure. When `aKind` is `User` they will get the user value if possible,
+  // and fall back to the default value otherwise.
+  static bool GetBool(const char* aPrefName, bool aFallback = false,
+                      PrefValueKind aKind = PrefValueKind::User);
+  static int32_t GetInt(const char* aPrefName, int32_t aFallback = 0,
+                        PrefValueKind aKind = PrefValueKind::User);
+  static uint32_t GetUint(const char* aPrefName, uint32_t aFallback = 0,
+                          PrefValueKind aKind = PrefValueKind::User);
+  static float GetFloat(const char* aPrefName, float aFallback = 0.0f,
+                        PrefValueKind aKind = PrefValueKind::User);
+
+  // Value setters. These fail if run outside the parent process.
+
+  static nsresult SetBool(const char* aPrefName, bool aValue,
+                          PrefValueKind aKind = PrefValueKind::User);
+  static nsresult SetInt(const char* aPrefName, int32_t aValue,
+                         PrefValueKind aKind = PrefValueKind::User);
+  static nsresult SetCString(const char* aPrefName, const nsACString& aValue,
+                             PrefValueKind aKind = PrefValueKind::User);
+
+  static nsresult SetUint(const char* aPrefName, uint32_t aValue,
+                          PrefValueKind aKind = PrefValueKind::User) {
+    return SetInt(aPrefName, static_cast<int32_t>(aValue), aKind);
+  }
+
+  static nsresult SetFloat(const char* aPrefName, float aValue,
+                           PrefValueKind aKind = PrefValueKind::User) {
+    nsAutoCString value;
+    value.AppendFloat(aValue);
+    return SetCString(aPrefName, value, aKind);
+  }
+
+  static nsresult SetCString(const char* aPrefName, const char* aValue,
+                             PrefValueKind aKind = PrefValueKind::User) {
+    return Preferences::SetCString(aPrefName, nsDependentCString(aValue),
+                                   aKind);
+  }
+
+  static nsresult SetString(const char* aPrefName, const char16ptr_t aValue,
+                            PrefValueKind aKind = PrefValueKind::User) {
+    return Preferences::SetCString(aPrefName, NS_ConvertUTF16toUTF8(aValue),
+                                   aKind);
+  }
+
+  static nsresult SetString(const char* aPrefName, const nsAString& aValue,
+                            PrefValueKind aKind = PrefValueKind::User) {
+    return Preferences::SetCString(aPrefName, NS_ConvertUTF16toUTF8(aValue),
+                                   aKind);
+  }
+
+  static nsresult SetComplex(const char* aPrefName, const nsIID& aType,
+                             nsISupports* aValue,
+                             PrefValueKind aKind = PrefValueKind::User);
+
+  static nsresult Lock(const char* aPrefName);
+  static nsresult Unlock(const char* aPrefName);
+  static bool IsLocked(const char* aPrefName);
+  static bool IsSanitized(const char* aPrefName);
+
+  // Clears user set pref. Fails if run outside the parent process.
+  static nsresult ClearUser(const char* aPrefName);
+
+  // Whether the pref has a user value or not.
+  static bool HasUserValue(const char* aPref);
+
+  // Whether the pref has a user value or not.
+  static bool HasDefaultValue(const char* aPref);
+
+  // Adds/Removes the observer for the root pref branch. See nsIPrefBranch.idl
+  // for details.
+  static nsresult AddStrongObserver(nsIObserver* aObserver,
+                                    const nsACString& aPref);
+  static nsresult AddWeakObserver(nsIObserver* aObserver,
+                                  const nsACString& aPref);
+  static nsresult RemoveObserver(nsIObserver* aObserver,
+                                 const nsACString& aPref);
+
+  template <int N>
+  static nsresult AddStrongObserver(nsIObserver* aObserver,
+                                    const char (&aPref)[N]) {
+    return AddStrongObserver(aObserver, nsLiteralCString(aPref));
+  }
+  template <int N>
+  static nsresult AddWeakObserver(nsIObserver* aObserver,
+                                  const char (&aPref)[N]) {
+    return AddWeakObserver(aObserver, nsLiteralCString(aPref));
+  }
+  template <int N>
+  static nsresult RemoveObserver(nsIObserver* aObserver,
+                                 const char (&aPref)[N]) {
+    return RemoveObserver(aObserver, nsLiteralCString(aPref));
+  }
+
+  // Adds/Removes two or more observers for the root pref branch. Pass to
+  // aPrefs an array of const char* whose last item is nullptr.
+  // Note: All preference strings *must* be statically-allocated string
+  // literals.
+  static nsresult AddStrongObservers(nsIObserver* aObserver,
+                                     const char** aPrefs);
+  static nsresult AddWeakObservers(nsIObserver* aObserver, const char** aPrefs);
+  static nsresult RemoveObservers(nsIObserver* aObserver, const char** aPrefs);
+
+  // Registers/Unregisters the callback function for the aPref.
+  template <typename T = void>
+  static nsresult RegisterCallback(PrefChangedFunc aCallback,
+                                   const nsACString& aPref,
+                                   T* aClosure = nullptr) {
+    return RegisterCallback(aCallback, aPref, aClosure, ExactMatch);
+  }
+
+  template <typename T = void>
+  static nsresult UnregisterCallback(PrefChangedFunc aCallback,
+                                     const nsACString& aPref,
+                                     T* aClosure = nullptr) {
+    return UnregisterCallback(aCallback, aPref, aClosure, ExactMatch);
+  }
+
+  // Like RegisterCallback, but also calls the callback immediately for
+  // initialization.
+  template <typename T = void>
+  static nsresult RegisterCallbackAndCall(PrefChangedFunc aCallback,
+                                          const nsACString& aPref,
+                                          T* aClosure = nullptr) {
+    return RegisterCallbackAndCall(aCallback, aPref, aClosure, ExactMatch);
+  }
+
+  // Like RegisterCallback, but registers a callback for a prefix of multiple
+  // pref names, not a single pref name.
+  template <typename T = void>
+  static nsresult RegisterPrefixCallback(PrefChangedFunc aCallback,
+                                         const nsACString& aPref,
+                                         T* aClosure = nullptr) {
+    return RegisterCallback(aCallback, aPref, aClosure, PrefixMatch);
+  }
+
+  // Like RegisterPrefixCallback, but also calls the callback immediately for
+  // initialization.
+  template <typename T = void>
+  static nsresult RegisterPrefixCallbackAndCall(PrefChangedFunc aCallback,
+                                                const nsACString& aPref,
+                                                T* aClosure = nullptr) {
+    return RegisterCallbackAndCall(aCallback, aPref, aClosure, PrefixMatch);
+  }
+
+  // Unregister a callback registered with RegisterPrefixCallback or
+  // RegisterPrefixCallbackAndCall.
+  template <typename T = void>
+  static nsresult UnregisterPrefixCallback(PrefChangedFunc aCallback,
+                                           const nsACString& aPref,
+                                           T* aClosure = nullptr) {
+    return UnregisterCallback(aCallback, aPref, aClosure, PrefixMatch);
+  }
+
+  // Variants of the above which register a single callback to handle multiple
+  // preferences.
+  //
+  // The array of preference names must be null terminated. It may be
+  // dynamically allocated, but the caller is responsible for keeping it alive
+  // until the callback is unregistered.
+  //
+  // Also note that the exact same aPrefs pointer must be passed to the
+  // Unregister call as was passed to the Register call.
+  template <typename T = void>
+  static nsresult RegisterCallbacks(PrefChangedFunc aCallback,
+                                    const char** aPrefs,
+                                    T* aClosure = nullptr) {
+    return RegisterCallbacks(aCallback, aPrefs, aClosure, ExactMatch);
+  }
+  static nsresult RegisterCallbacksAndCall(PrefChangedFunc aCallback,
+                                           const char** aPrefs,
+                                           void* aClosure = nullptr);
+  template <typename T = void>
+  static nsresult UnregisterCallbacks(PrefChangedFunc aCallback,
+                                      const char** aPrefs,
+                                      T* aClosure = nullptr) {
+    return UnregisterCallbacks(aCallback, aPrefs, aClosure, ExactMatch);
+  }
+  template <typename T = void>
+  static nsresult RegisterPrefixCallbacks(PrefChangedFunc aCallback,
+                                          const char** aPrefs,
+                                          T* aClosure = nullptr) {
+    return RegisterCallbacks(aCallback, aPrefs, aClosure, PrefixMatch);
+  }
+  template <typename T = void>
+  static nsresult UnregisterPrefixCallbacks(PrefChangedFunc aCallback,
+                                            const char** aPrefs,
+                                            T* aClosure = nullptr) {
+    return UnregisterCallbacks(aCallback, aPrefs, aClosure, PrefixMatch);
+  }
+
+  template <int N, typename T = void>
+  static nsresult RegisterCallback(PrefChangedFunc aCallback,
+                                   const char (&aPref)[N],
+                                   T* aClosure = nullptr) {
+    return RegisterCallback(aCallback, nsLiteralCString(aPref), aClosure,
+                            ExactMatch);
+  }
+
+  template <int N, typename T = void>
+  static nsresult UnregisterCallback(PrefChangedFunc aCallback,
+                                     const char (&aPref)[N],
+                                     T* aClosure = nullptr) {
+    return UnregisterCallback(aCallback, nsLiteralCString(aPref), aClosure,
+                              ExactMatch);
+  }
+
+  template <int N, typename T = void>
+  static nsresult RegisterCallbackAndCall(PrefChangedFunc aCallback,
+                                          const char (&aPref)[N],
+                                          T* aClosure = nullptr) {
+    return RegisterCallbackAndCall(aCallback, nsLiteralCString(aPref), aClosure,
+                                   ExactMatch);
+  }
+
+  template <int N, typename T = void>
+  static nsresult RegisterPrefixCallback(PrefChangedFunc aCallback,
+                                         const char (&aPref)[N],
+                                         T* aClosure = nullptr) {
+    return RegisterCallback(aCallback, nsLiteralCString(aPref), aClosure,
+                            PrefixMatch);
+  }
+
+  template <int N, typename T = void>
+  static nsresult RegisterPrefixCallbackAndCall(PrefChangedFunc aCallback,
+                                                const char (&aPref)[N],
+                                                T* aClosure = nullptr) {
+    return RegisterCallbackAndCall(aCallback, nsLiteralCString(aPref), aClosure,
+                                   PrefixMatch);
+  }
+
+  template <int N, typename T = void>
+  static nsresult UnregisterPrefixCallback(PrefChangedFunc aCallback,
+                                           const char (&aPref)[N],
+                                           T* aClosure = nullptr) {
+    return UnregisterCallback(aCallback, nsLiteralCString(aPref), aClosure,
+                              PrefixMatch);
+  }
+
+  // When a content process is created these methods are used to pass changed
+  // prefs in bulk from the parent process, via shared memory.
+  static void SerializePreferences(nsCString& aStr,
+                                   bool aIsDestinationWebContentProcess);
+  static void DeserializePreferences(char* aStr, size_t aPrefsLen);
+
+  static mozilla::ipc::FileDescriptor EnsureSnapshot(size_t* aSize);
+  static void InitSnapshot(const mozilla::ipc::FileDescriptor&, size_t aSize);
+
+  // When a single pref is changed in the parent process, these methods are
+  // used to pass the update to content processes.
+  static void GetPreference(dom::Pref* aPref,
+                            const GeckoProcessType aDestinationProcessType,
+                            const nsACString& aDestinationRemoteType);
+  static void SetPreference(const dom::Pref& aPref);
+
+#ifdef DEBUG
+  static bool ArePrefsInitedInContentProcess();
+#endif
+
+  static void AddSizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf,
+                                     PrefsSizes& aSizes);
+
+  static void HandleDirty();
+
+  // Explicitly choosing synchronous or asynchronous (if allowed) preferences
+  // file write. Only for the default file.  The guarantee for the "blocking"
+  // is that when it returns, the file on disk reflect the current state of
+  // preferences.
+  nsresult SavePrefFileBlocking();
+  nsresult SavePrefFileAsynchronous();
+
+  // If this is false, only blocking writes, on main thread are allowed.
+  bool AllowOffMainThreadSave();
+
+ private:
+  virtual ~Preferences();
+
+  nsresult NotifyServiceObservers(const char* aSubject);
+
+  // Loads the prefs.js file from the profile, or creates a new one. Returns
+  // the prefs file if successful, or nullptr on failure.
+  already_AddRefed<nsIFile> ReadSavedPrefs();
+
+  // Loads the user.js file from the profile if present.
+  void ReadUserOverridePrefs();
+
+  nsresult MakeBackupPrefFile(nsIFile* aFile);
+
+  // Default pref file save can be blocking or not.
+  enum class SaveMethod { Blocking, Asynchronous };
+
+  // Off main thread is only respected for the default aFile value (nullptr).
+  nsresult SavePrefFileInternal(nsIFile* aFile, SaveMethod aSaveMethod);
+  nsresult WritePrefFile(nsIFile* aFile, SaveMethod aSaveMethod);
+
+  nsresult ResetUserPrefs();
+
+  // Helpers for implementing
+  // Register(Prefix)Callback/Unregister(Prefix)Callback.
+ public:
+  // Public so the ValueObserver classes can use it.
+  enum MatchKind {
+    PrefixMatch,
+    ExactMatch,
+  };
+
+ private:
+  static void SetupTelemetryPref();
+  static nsresult InitInitialObjects(bool aIsStartup);
+
+  friend struct Internals;
+
+  static nsresult RegisterCallback(PrefChangedFunc aCallback,
+                                   const nsACString& aPref, void* aClosure,
+                                   MatchKind aMatchKind,
+                                   bool aIsPriority = false);
+  static nsresult UnregisterCallback(PrefChangedFunc aCallback,
+                                     const nsACString& aPref, void* aClosure,
+                                     MatchKind aMatchKind);
+  static nsresult RegisterCallbackAndCall(PrefChangedFunc aCallback,
+                                          const nsACString& aPref,
+                                          void* aClosure, MatchKind aMatchKind);
+
+  static nsresult RegisterCallbacks(PrefChangedFunc aCallback,
+                                    const char** aPrefs, void* aClosure,
+                                    MatchKind aMatchKind);
+  static nsresult UnregisterCallbacks(PrefChangedFunc aCallback,
+                                      const char** aPrefs, void* aClosure,
+                                      MatchKind aMatchKind);
+
+  template <typename T>
+  static nsresult RegisterCallbackImpl(PrefChangedFunc aCallback, T& aPref,
+                                       void* aClosure, MatchKind aMatchKind,
+                                       bool aIsPriority = false);
+  template <typename T>
+  static nsresult UnregisterCallbackImpl(PrefChangedFunc aCallback, T& aPref,
+                                         void* aClosure, MatchKind aMatchKind);
+
+  static nsresult RegisterCallback(PrefChangedFunc aCallback, const char* aPref,
+                                   void* aClosure, MatchKind aMatchKind,
+                                   bool aIsPriority = false) {
+    return RegisterCallback(aCallback, nsDependentCString(aPref), aClosure,
+                            aMatchKind, aIsPriority);
+  }
+  static nsresult UnregisterCallback(PrefChangedFunc aCallback,
+                                     const char* aPref, void* aClosure,
+                                     MatchKind aMatchKind) {
+    return UnregisterCallback(aCallback, nsDependentCString(aPref), aClosure,
+                              aMatchKind);
+  }
+  static nsresult RegisterCallbackAndCall(PrefChangedFunc aCallback,
+                                          const char* aPref, void* aClosure,
+                                          MatchKind aMatchKind) {
+    return RegisterCallbackAndCall(aCallback, nsDependentCString(aPref),
+                                   aClosure, aMatchKind);
+  }
+
+ private:
+  nsCOMPtr<nsIFile> mCurrentFile;
+  bool mDirty = false;
+  bool mProfileShutdown = false;
+  // We wait a bit after prefs are dirty before writing them. In this period,
+  // mDirty and mSavePending will both be true.
+  bool mSavePending = false;
+
+  nsCOMPtr<nsIPrefBranch> mRootBranch;
+  nsCOMPtr<nsIPrefBranch> mDefaultRootBranch;
+
+  static StaticRefPtr<Preferences> sPreferences;
+  static bool sShutdown;
+
+  // Init static members. Returns true on success.
+  static bool InitStaticMembers();
+};
+
+extern Atomic<bool, Relaxed> sOmitBlocklistedPrefValues;
+extern Atomic<bool, Relaxed> sCrashOnBlocklistedPref;
+
+bool IsPreferenceSanitized(const char* aPref);
+
+const char kFissionEnforceBlockList[] =
+    "fission.enforceBlocklistedPrefsInSubprocesses";
+const char kFissionOmitBlockListValues[] =
+    "fission.omitBlocklistedPrefsInSubprocesses";
+
+void OnFissionBlocklistPrefChange(const char* aPref, void* aData);
+
+}  // namespace mozilla
+
+#endif  // mozilla_Preferences_h