DXR is a code search and navigation tool aimed at making sense of large projects. It supports full-text and regex searches as well as structural queries.

Mercurial (d1ed7de67f5a)

VCS Links

Line Code
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
/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-*/
/* vim: set ts=2 sw=2 et tw=79: */
/* 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/. */

/**
 * A header for declaring various things that binding implementation headers
 * might need.  The idea is to make binding implementation headers safe to
 * include anywhere without running into include hell like we do with
 * BindingUtils.h
 */
#ifndef mozilla_dom_BindingDeclarations_h__
#define mozilla_dom_BindingDeclarations_h__

#include "nsStringGlue.h"
#include "js/Value.h"
#include "js/RootingAPI.h"
#include "mozilla/Maybe.h"
#include "nsCOMPtr.h"
#include "nsTArray.h"
#include "nsAutoPtr.h" // for nsRefPtr member variables
#include "mozilla/dom/DOMString.h"
#include "mozilla/dom/OwningNonNull.h"

class nsWrapperCache;

namespace mozilla {
namespace dom {

// Struct that serves as a base class for all dictionaries.  Particularly useful
// so we can use IsBaseOf to detect dictionary template arguments.
struct DictionaryBase
{
protected:
  bool ParseJSON(JSContext* aCx, const nsAString& aJSON,
                 JS::MutableHandle<JS::Value> aVal);

  bool StringifyToJSON(JSContext* aCx,
                       JS::MutableHandle<JS::Value> aValue,
                       nsAString& aJSON);
private:
  // aString is expected to actually be an nsAString*.  Should only be
  // called from StringifyToJSON.
  static bool AppendJSONToString(const jschar* aJSONData, uint32_t aDataLength,
                                 void* aString);
};

// Struct that serves as a base class for all typed arrays and array buffers and
// array buffer views.  Particularly useful so we can use IsBaseOf to detect
// typed array/buffer/view template arguments.
struct AllTypedArraysBase {
};

// Struct that serves as a base class for all owning unions.
// Particularly useful so we can use IsBaseOf to detect owning union
// template arguments.
struct AllOwningUnionBase {
};


struct EnumEntry {
  const char* value;
  size_t length;
};

class MOZ_STACK_CLASS GlobalObject
{
public:
  GlobalObject(JSContext* aCx, JSObject* aObject);

  JSObject* Get() const
  {
    return mGlobalJSObject;
  }

  nsISupports* GetAsSupports() const;

  // The context that this returns is not guaranteed to be in the compartment of
  // the object returned from Get(), in fact it's generally in the caller's
  // compartment.
  JSContext* Context() const
  {
    return mCx;
  }

  bool Failed() const
  {
    return !Get();
  }

protected:
  JS::Rooted<JSObject*> mGlobalJSObject;
  JSContext* mCx;
  mutable nsISupports* mGlobalObject;
  mutable nsCOMPtr<nsISupports> mGlobalObjectRef;
};

// Class for representing optional arguments.
template<typename T, typename InternalType>
class Optional_base
{
public:
  Optional_base()
  {}

  explicit Optional_base(const T& aValue)
  {
    mImpl.emplace(aValue);
  }

  template<typename T1, typename T2>
  explicit Optional_base(const T1& aValue1, const T2& aValue2)
  {
    mImpl.emplace(aValue1, aValue2);
  }

  bool WasPassed() const
  {
    return mImpl.isSome();
  }

  // Return InternalType here so we can work with it usefully.
  InternalType& Construct()
  {
    mImpl.emplace();
    return *mImpl;
  }

  template <class T1>
  InternalType& Construct(const T1 &t1)
  {
    mImpl.emplace(t1);
    return *mImpl;
  }

  template <class T1, class T2>
  InternalType& Construct(const T1 &t1, const T2 &t2)
  {
    mImpl.emplace(t1, t2);
    return *mImpl;
  }

  void Reset()
  {
    mImpl.reset();
  }

  const T& Value() const
  {
    return *mImpl;
  }

  // Return InternalType here so we can work with it usefully.
  InternalType& Value()
  {
    return *mImpl;
  }

  // And an explicit way to get the InternalType even if we're const.
  const InternalType& InternalValue() const
  {
    return *mImpl;
  }

  // If we ever decide to add conversion operators for optional arrays
  // like the ones Nullable has, we'll need to ensure that Maybe<> has
  // the boolean before the actual data.

private:
  // Forbid copy-construction and assignment
  Optional_base(const Optional_base& other) MOZ_DELETE;
  const Optional_base &operator=(const Optional_base &other) MOZ_DELETE;

protected:
  Maybe<InternalType> mImpl;
};

template<typename T>
class Optional : public Optional_base<T, T>
{
public:
  Optional() :
    Optional_base<T, T>()
  {}

  explicit Optional(const T& aValue) :
    Optional_base<T, T>(aValue)
  {}
};

template<typename T>
class Optional<JS::Handle<T> > :
  public Optional_base<JS::Handle<T>, JS::Rooted<T> >
{
public:
  Optional() :
    Optional_base<JS::Handle<T>, JS::Rooted<T> >()
  {}

  explicit Optional(JSContext* cx) :
    Optional_base<JS::Handle<T>, JS::Rooted<T> >()
  {
    this->Construct(cx);
  }

  Optional(JSContext* cx, const T& aValue) :
    Optional_base<JS::Handle<T>, JS::Rooted<T> >(cx, aValue)
  {}

  // Override the const Value() to return the right thing so we're not
  // returning references to temporaries.
  JS::Handle<T> Value() const
  {
    return *this->mImpl;
  }

  // And we have to override the non-const one too, since we're
  // shadowing the one on the superclass.
  JS::Rooted<T>& Value()
  {
    return *this->mImpl;
  }
};

// A specialization of Optional for JSObject* to make sure that when someone
// calls Construct() on it we will pre-initialized the JSObject* to nullptr so
// it can be traced safely.
template<>
class Optional<JSObject*> : public Optional_base<JSObject*, JSObject*>
{
public:
  Optional() :
    Optional_base<JSObject*, JSObject*>()
  {}

  explicit Optional(JSObject* aValue) :
    Optional_base<JSObject*, JSObject*>(aValue)
  {}

  // Don't allow us to have an uninitialized JSObject*
  JSObject*& Construct()
  {
    // The Android compiler sucks and thinks we're trying to construct
    // a JSObject* from an int if we don't cast here.  :(
    return Optional_base<JSObject*, JSObject*>::Construct(
      static_cast<JSObject*>(nullptr));
  }

  template <class T1>
  JSObject*& Construct(const T1& t1)
  {
    return Optional_base<JSObject*, JSObject*>::Construct(t1);
  }
};

// A specialization of Optional for JS::Value to make sure no one ever uses it.
template<>
class Optional<JS::Value>
{
private:
  Optional() MOZ_DELETE;

  explicit Optional(JS::Value aValue) MOZ_DELETE;
};

// A specialization of Optional for NonNull that lets us get a T& from Value()
template<typename U> class NonNull;
template<typename T>
class Optional<NonNull<T> > : public Optional_base<T, NonNull<T> >
{
public:
  // We want our Value to actually return a non-const reference, even
  // if we're const.  At least for things that are normally pointer
  // types...
  T& Value() const
  {
    return *this->mImpl->get();
  }

  // And we have to override the non-const one too, since we're
  // shadowing the one on the superclass.
  NonNull<T>& Value()
  {
    return *this->mImpl;
  }
};

// A specialization of Optional for OwningNonNull that lets us get a
// T& from Value()
template<typename T>
class Optional<OwningNonNull<T> > : public Optional_base<T, OwningNonNull<T> >
{
public:
  // We want our Value to actually return a non-const reference, even
  // if we're const.  At least for things that are normally pointer
  // types...
  T& Value() const
  {
    return *this->mImpl->get();
  }

  // And we have to override the non-const one too, since we're
  // shadowing the one on the superclass.
  OwningNonNull<T>& Value()
  {
    return *this->mImpl;
  }
};

// Specialization for strings.
// XXXbz we can't pull in FakeString here, because it depends on internal
// strings.  So we just have to forward-declare it and reimplement its
// ToAStringPtr.

namespace binding_detail {
struct FakeString;
} // namespace binding_detail

template<>
class Optional<nsAString>
{
public:
  Optional() : mPassed(false) {}

  bool WasPassed() const
  {
    return mPassed;
  }

  void operator=(const nsAString* str)
  {
    MOZ_ASSERT(str);
    mStr = str;
    mPassed = true;
  }

  // If this code ever goes away, remove the comment pointing to it in the
  // FakeString class in BindingUtils.h.
  void operator=(const binding_detail::FakeString* str)
  {
    MOZ_ASSERT(str);
    mStr = reinterpret_cast<const nsString*>(str);
    mPassed = true;
  }

  const nsAString& Value() const
  {
    MOZ_ASSERT(WasPassed());
    return *mStr;
  }

private:
  // Forbid copy-construction and assignment
  Optional(const Optional& other) MOZ_DELETE;
  const Optional &operator=(const Optional &other) MOZ_DELETE;

  bool mPassed;
  const nsAString* mStr;
};

template<class T>
class NonNull
{
public:
  NonNull()
#ifdef DEBUG
    : inited(false)
#endif
  {}

  // This is no worse than get() in terms of const handling.
  operator T&() const {
    MOZ_ASSERT(inited);
    MOZ_ASSERT(ptr, "NonNull<T> was set to null");
    return *ptr;
  }

  operator T*() const {
    MOZ_ASSERT(inited);
    MOZ_ASSERT(ptr, "NonNull<T> was set to null");
    return ptr;
  }

  void operator=(T* t) {
    ptr = t;
    MOZ_ASSERT(ptr);
#ifdef DEBUG
    inited = true;
#endif
  }

  template<typename U>
  void operator=(U* t) {
    ptr = t->ToAStringPtr();
    MOZ_ASSERT(ptr);
#ifdef DEBUG
    inited = true;
#endif
  }

  T** Slot() {
#ifdef DEBUG
    inited = true;
#endif
    return &ptr;
  }

  T* Ptr() {
    MOZ_ASSERT(inited);
    MOZ_ASSERT(ptr, "NonNull<T> was set to null");
    return ptr;
  }

  // Make us work with smart-ptr helpers that expect a get()
  T* get() const {
    MOZ_ASSERT(inited);
    MOZ_ASSERT(ptr);
    return ptr;
  }

protected:
  T* ptr;
#ifdef DEBUG
  bool inited;
#endif
};

// Class for representing sequences in arguments.  We use a non-auto array
// because that allows us to use sequences of sequences and the like.  This
// needs to be fallible because web content controls the length of the array,
// and can easily try to create very large lengths.
template<typename T>
class Sequence : public FallibleTArray<T>
{
public:
  Sequence() : FallibleTArray<T>()
  {}
};

inline nsWrapperCache*
GetWrapperCache(nsWrapperCache* cache)
{
  return cache;
}

inline nsWrapperCache*
GetWrapperCache(void* p)
{
  return nullptr;
}

// Helper template for smart pointers to resolve ambiguity between
// GetWrappeCache(void*) and GetWrapperCache(const ParentObject&).
template <template <typename> class SmartPtr, typename T>
inline nsWrapperCache*
GetWrapperCache(const SmartPtr<T>& aObject)
{
  return GetWrapperCache(aObject.get());
}

struct ParentObject {
  template<class T>
  ParentObject(T* aObject) :
    mObject(aObject),
    mWrapperCache(GetWrapperCache(aObject)),
    mUseXBLScope(false)
  {}

  template<class T, template<typename> class SmartPtr>
  ParentObject(const SmartPtr<T>& aObject) :
    mObject(aObject.get()),
    mWrapperCache(GetWrapperCache(aObject.get())),
    mUseXBLScope(false)
  {}

  ParentObject(nsISupports* aObject, nsWrapperCache* aCache) :
    mObject(aObject),
    mWrapperCache(aCache),
    mUseXBLScope(false)
  {}

  nsISupports* const mObject;
  nsWrapperCache* const mWrapperCache;
  bool mUseXBLScope;
};

} // namespace dom
} // namespace mozilla

#endif // mozilla_dom_BindingDeclarations_h__