1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560
|
/* -*- 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/MozPromise.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:
using WritePrefFilePromise = MozPromise<bool, nsresult, false>;
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* const* aPrefs);
static nsresult AddWeakObservers(nsIObserver* aObserver,
const char* const* aPrefs);
static nsresult RemoveObservers(nsIObserver* aObserver,
const char* const* 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* const* aPrefs,
T* aClosure = nullptr) {
return RegisterCallbacks(aCallback, aPrefs, aClosure, ExactMatch);
}
static nsresult RegisterCallbacksAndCall(PrefChangedFunc aCallback,
const char* const* aPrefs,
void* aClosure = nullptr);
template <typename T = void>
static nsresult UnregisterCallbacks(PrefChangedFunc aCallback,
const char* const* aPrefs,
T* aClosure = nullptr) {
return UnregisterCallbacks(aCallback, aPrefs, aClosure, ExactMatch);
}
template <typename T = void>
static nsresult RegisterPrefixCallbacks(PrefChangedFunc aCallback,
const char* const* aPrefs,
T* aClosure = nullptr) {
return RegisterCallbacks(aCallback, aPrefs, aClosure, PrefixMatch);
}
template <typename T = void>
static nsresult UnregisterPrefixCallbacks(PrefChangedFunc aCallback,
const char* const* 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,
UniquePtr<MozPromiseHolder<WritePrefFilePromise>> aPromise = nullptr);
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* const* aPrefs, void* aClosure,
MatchKind aMatchKind);
static nsresult UnregisterCallbacks(PrefChangedFunc aCallback,
const char* const* 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;
// Time since unix epoch in ms (JS Date compatible)
PRTime mUserPrefsFileLastModifiedAtStartup = 0;
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
|