2 * Copyright 2017 Facebook, Inc.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
20 #include <boost/iterator/iterator_adaptor.hpp>
21 #include <boost/iterator/iterator_facade.hpp>
22 #include <folly/Likely.h>
23 #include <folly/Conv.h>
24 #include <folly/Format.h>
26 //////////////////////////////////////////////////////////////////////
31 struct hash< ::folly::dynamic> {
32 size_t operator()(::folly::dynamic const& d) const {
39 //////////////////////////////////////////////////////////////////////
41 // This is a higher-order preprocessor macro to aid going from runtime
42 // types to the compile time type system.
43 #define FB_DYNAMIC_APPLY(type, apply) \
73 //////////////////////////////////////////////////////////////////////
77 struct TypeError : std::runtime_error {
78 explicit TypeError(const std::string& expected, dynamic::Type actual);
79 explicit TypeError(const std::string& expected,
80 dynamic::Type actual1, dynamic::Type actual2);
85 //////////////////////////////////////////////////////////////////////
89 // This helper is used in destroy() to be able to run destructors on
90 // types like "int64_t" without a compiler error.
92 template<class T> static void destroy(T* t) { t->~T(); }
96 * Helper for implementing numeric conversions in operators on
97 * numbers. Just promotes to double when one of the arguments is
98 * double, or throws if either is not a numeric type.
100 template<template<class> class Op>
101 dynamic numericOp(dynamic const& a, dynamic const& b) {
102 if (!a.isNumber() || !b.isNumber()) {
103 throw TypeError("numeric", a.type(), b.type());
105 if (a.type() != b.type()) {
106 auto& integ = a.isInt() ? a : b;
107 auto& nonint = a.isInt() ? b : a;
108 return Op<double>()(to<double>(integ.asInt()), nonint.asDouble());
111 return Op<double>()(a.asDouble(), b.asDouble());
113 return Op<int64_t>()(a.asInt(), b.asInt());
118 //////////////////////////////////////////////////////////////////////
121 * We're doing this instead of a simple member typedef to avoid the
122 * undefined behavior of parameterizing std::unordered_map<> with an
125 * Note: Later we may add separate order tracking here (a multi-index
128 struct dynamic::ObjectImpl : std::unordered_map<dynamic, dynamic> {};
130 //////////////////////////////////////////////////////////////////////
132 // Helper object for creating objects conveniently. See object and
133 // the dynamic::dynamic(ObjectMaker&&) ctor.
134 struct dynamic::ObjectMaker {
135 friend struct dynamic;
137 explicit ObjectMaker() : val_(dynamic::object) {}
138 explicit ObjectMaker(dynamic key, dynamic val)
139 : val_(dynamic::object)
141 val_.insert(std::move(key), std::move(val));
144 // Make sure no one tries to save one of these into an lvalue with
145 // auto or anything like that.
146 ObjectMaker(ObjectMaker&&) = default;
147 ObjectMaker(ObjectMaker const&) = delete;
148 ObjectMaker& operator=(ObjectMaker const&) = delete;
149 ObjectMaker& operator=(ObjectMaker&&) = delete;
151 // This returns an rvalue-reference instead of an lvalue-reference
152 // to allow constructs like this to moved instead of copied:
153 // dynamic a = dynamic::object("a", "b")("c", "d")
154 ObjectMaker&& operator()(dynamic key, dynamic val) {
155 val_.insert(std::move(key), std::move(val));
156 return std::move(*this);
163 inline void dynamic::array(EmptyArrayTag) {}
165 template <class... Args>
166 inline dynamic dynamic::array(Args&& ...args) {
167 return dynamic(Array{std::forward<Args>(args)...});
170 inline dynamic::ObjectMaker dynamic::object() { return ObjectMaker(); }
171 inline dynamic::ObjectMaker dynamic::object(dynamic a, dynamic b) {
172 return ObjectMaker(std::move(a), std::move(b));
175 //////////////////////////////////////////////////////////////////////
177 struct dynamic::const_item_iterator
178 : boost::iterator_adaptor<dynamic::const_item_iterator,
179 dynamic::ObjectImpl::const_iterator> {
180 /* implicit */ const_item_iterator(base_type b) : iterator_adaptor_(b) { }
183 friend class boost::iterator_core_access;
186 struct dynamic::const_key_iterator
187 : boost::iterator_adaptor<dynamic::const_key_iterator,
188 dynamic::ObjectImpl::const_iterator,
190 /* implicit */ const_key_iterator(base_type b) : iterator_adaptor_(b) { }
193 dynamic const& dereference() const {
194 return base_reference()->first;
196 friend class boost::iterator_core_access;
199 struct dynamic::const_value_iterator
200 : boost::iterator_adaptor<dynamic::const_value_iterator,
201 dynamic::ObjectImpl::const_iterator,
203 /* implicit */ const_value_iterator(base_type b) : iterator_adaptor_(b) { }
206 dynamic const& dereference() const {
207 return base_reference()->second;
209 friend class boost::iterator_core_access;
212 //////////////////////////////////////////////////////////////////////
214 inline dynamic::dynamic() : dynamic(nullptr) {}
216 inline dynamic::dynamic(std::nullptr_t) : type_(NULLT) {}
218 inline dynamic::dynamic(void (*)(EmptyArrayTag))
221 new (&u_.array) Array();
224 inline dynamic::dynamic(ObjectMaker (*)())
227 new (getAddress<ObjectImpl>()) ObjectImpl();
230 inline dynamic::dynamic(StringPiece s)
233 new (&u_.string) std::string(s.data(), s.size());
236 inline dynamic::dynamic(char const* s)
239 new (&u_.string) std::string(s);
242 inline dynamic::dynamic(std::string s)
245 new (&u_.string) std::string(std::move(s));
248 inline dynamic::dynamic(ObjectMaker&& maker)
251 new (getAddress<ObjectImpl>())
252 ObjectImpl(std::move(*maker.val_.getAddress<ObjectImpl>()));
255 inline dynamic::dynamic(dynamic const& o)
261 inline dynamic::dynamic(dynamic&& o) noexcept
264 *this = std::move(o);
267 inline dynamic::~dynamic() noexcept { destroy(); }
269 // Integral types except bool convert to int64_t, float types to double.
271 struct dynamic::NumericTypeHelper<
272 T, typename std::enable_if<std::is_integral<T>::value>::type> {
273 using type = int64_t;
276 struct dynamic::NumericTypeHelper<bool> {
280 struct dynamic::NumericTypeHelper<float> {
284 struct dynamic::NumericTypeHelper<double> {
288 template<class T, class NumericType /* = typename NumericTypeHelper<T>::type */>
289 dynamic::dynamic(T t) {
290 type_ = TypeInfo<NumericType>::type;
291 new (getAddress<NumericType>()) NumericType(NumericType(t));
294 template <class Iterator>
295 dynamic::dynamic(Iterator first, Iterator last)
298 new (&u_.array) Array(first, last);
301 //////////////////////////////////////////////////////////////////////
303 inline dynamic::const_iterator dynamic::begin() const {
304 return get<Array>().begin();
306 inline dynamic::const_iterator dynamic::end() const {
307 return get<Array>().end();
311 struct dynamic::IterableProxy {
312 typedef It const_iterator;
313 typedef typename It::value_type value_type;
315 /* implicit */ IterableProxy(const dynamic::ObjectImpl* o) : o_(o) { }
326 const dynamic::ObjectImpl* o_;
329 inline dynamic::IterableProxy<dynamic::const_key_iterator> dynamic::keys()
331 return &(get<ObjectImpl>());
334 inline dynamic::IterableProxy<dynamic::const_value_iterator> dynamic::values()
336 return &(get<ObjectImpl>());
339 inline dynamic::IterableProxy<dynamic::const_item_iterator> dynamic::items()
341 return &(get<ObjectImpl>());
344 inline bool dynamic::isString() const {
345 return get_nothrow<std::string>() != nullptr;
347 inline bool dynamic::isObject() const {
348 return get_nothrow<ObjectImpl>() != nullptr;
350 inline bool dynamic::isBool() const {
351 return get_nothrow<bool>() != nullptr;
353 inline bool dynamic::isArray() const {
354 return get_nothrow<Array>() != nullptr;
356 inline bool dynamic::isDouble() const {
357 return get_nothrow<double>() != nullptr;
359 inline bool dynamic::isInt() const {
360 return get_nothrow<int64_t>() != nullptr;
362 inline bool dynamic::isNull() const {
363 return get_nothrow<void*>() != nullptr;
365 inline bool dynamic::isNumber() const {
366 return isInt() || isDouble();
369 inline dynamic::Type dynamic::type() const {
373 inline std::string dynamic::asString() const {
374 return asImpl<std::string>();
376 inline double dynamic::asDouble() const {
377 return asImpl<double>();
379 inline int64_t dynamic::asInt() const {
380 return asImpl<int64_t>();
382 inline bool dynamic::asBool() const {
383 return asImpl<bool>();
386 inline const std::string& dynamic::getString() const& {
387 return get<std::string>();
389 inline double dynamic::getDouble() const& { return get<double>(); }
390 inline int64_t dynamic::getInt() const& { return get<int64_t>(); }
391 inline bool dynamic::getBool() const& { return get<bool>(); }
393 inline std::string& dynamic::getString()& {
394 return get<std::string>();
396 inline double& dynamic::getDouble() & { return get<double>(); }
397 inline int64_t& dynamic::getInt() & { return get<int64_t>(); }
398 inline bool& dynamic::getBool() & { return get<bool>(); }
400 inline std::string&& dynamic::getString()&& {
401 return std::move(get<std::string>());
403 inline double dynamic::getDouble() && { return get<double>(); }
404 inline int64_t dynamic::getInt() && { return get<int64_t>(); }
405 inline bool dynamic::getBool() && { return get<bool>(); }
407 inline const char* dynamic::data() const& {
408 return get<std::string>().data();
410 inline const char* dynamic::c_str() const& {
411 return get<std::string>().c_str();
413 inline StringPiece dynamic::stringPiece() const {
414 return get<std::string>();
418 struct dynamic::CompareOp {
419 static bool comp(T const& a, T const& b) { return a < b; }
422 struct dynamic::CompareOp<dynamic::ObjectImpl> {
423 static bool comp(ObjectImpl const&, ObjectImpl const&) {
424 // This code never executes; it is just here for the compiler.
429 inline dynamic& dynamic::operator+=(dynamic const& o) {
430 if (type() == STRING && o.type() == STRING) {
431 *getAddress<std::string>() += *o.getAddress<std::string>();
434 *this = detail::numericOp<std::plus>(*this, o);
438 inline dynamic& dynamic::operator-=(dynamic const& o) {
439 *this = detail::numericOp<std::minus>(*this, o);
443 inline dynamic& dynamic::operator*=(dynamic const& o) {
444 *this = detail::numericOp<std::multiplies>(*this, o);
448 inline dynamic& dynamic::operator/=(dynamic const& o) {
449 *this = detail::numericOp<std::divides>(*this, o);
453 #define FB_DYNAMIC_INTEGER_OP(op) \
454 inline dynamic& dynamic::operator op(dynamic const& o) { \
455 if (!isInt() || !o.isInt()) { \
456 throw TypeError("int64", type(), o.type()); \
458 *getAddress<int64_t>() op o.asInt(); \
462 FB_DYNAMIC_INTEGER_OP(%=)
463 FB_DYNAMIC_INTEGER_OP(|=)
464 FB_DYNAMIC_INTEGER_OP(&=)
465 FB_DYNAMIC_INTEGER_OP(^=)
467 #undef FB_DYNAMIC_INTEGER_OP
469 inline dynamic& dynamic::operator++() {
474 inline dynamic& dynamic::operator--() {
479 inline dynamic const& dynamic::operator[](dynamic const& idx) const& {
483 inline dynamic&& dynamic::operator[](dynamic const& idx) && {
484 return std::move((*this)[idx]);
487 template<class K, class V> inline dynamic& dynamic::setDefault(K&& k, V&& v) {
488 auto& obj = get<ObjectImpl>();
489 return obj.insert(std::make_pair(std::forward<K>(k),
490 std::forward<V>(v))).first->second;
493 template<class K> inline dynamic& dynamic::setDefault(K&& k, dynamic&& v) {
494 auto& obj = get<ObjectImpl>();
495 return obj.insert(std::make_pair(std::forward<K>(k),
496 std::move(v))).first->second;
499 template<class K> inline dynamic& dynamic::setDefault(K&& k, const dynamic& v) {
500 auto& obj = get<ObjectImpl>();
501 return obj.insert(std::make_pair(std::forward<K>(k), v)).first->second;
504 inline dynamic* dynamic::get_ptr(dynamic const& idx) & {
505 return const_cast<dynamic*>(const_cast<dynamic const*>(this)->get_ptr(idx));
508 inline dynamic& dynamic::at(dynamic const& idx) & {
509 return const_cast<dynamic&>(const_cast<dynamic const*>(this)->at(idx));
512 inline dynamic&& dynamic::at(dynamic const& idx) && {
513 return std::move(at(idx));
516 inline bool dynamic::empty() const {
523 inline std::size_t dynamic::count(dynamic const& key) const {
524 return find(key) != items().end() ? 1u : 0u;
527 inline dynamic::const_item_iterator dynamic::find(dynamic const& key) const {
528 return get<ObjectImpl>().find(key);
531 template<class K, class V> inline void dynamic::insert(K&& key, V&& val) {
532 auto& obj = get<ObjectImpl>();
533 auto rv = obj.insert({ std::forward<K>(key), nullptr });
534 rv.first->second = std::forward<V>(val);
537 inline void dynamic::update(const dynamic& mergeObj) {
538 if (!isObject() || !mergeObj.isObject()) {
539 throw TypeError("object", type(), mergeObj.type());
542 for (const auto& pair : mergeObj.items()) {
543 (*this)[pair.first] = pair.second;
547 inline void dynamic::update_missing(const dynamic& mergeObj1) {
548 if (!isObject() || !mergeObj1.isObject()) {
549 throw TypeError("object", type(), mergeObj1.type());
552 // Only add if not already there
553 for (const auto& pair : mergeObj1.items()) {
554 if ((*this).find(pair.first) == (*this).items().end()) {
555 (*this)[pair.first] = pair.second;
560 inline dynamic dynamic::merge(
561 const dynamic& mergeObj1,
562 const dynamic& mergeObj2) {
564 // No checks on type needed here because they are done in update_missing
565 // Note that we do update_missing here instead of update() because
566 // it will prevent the extra writes that would occur with update()
567 auto ret = mergeObj2;
568 ret.update_missing(mergeObj1);
572 inline std::size_t dynamic::erase(dynamic const& key) {
573 auto& obj = get<ObjectImpl>();
574 return obj.erase(key);
577 inline dynamic::const_iterator dynamic::erase(const_iterator it) {
578 auto& arr = get<Array>();
579 // std::vector doesn't have an erase method that works on const iterators,
580 // even though the standard says it should, so this hack converts to a
581 // non-const iterator before calling erase.
582 return get<Array>().erase(arr.begin() + (it - arr.begin()));
585 inline dynamic::const_key_iterator dynamic::erase(const_key_iterator it) {
586 return const_key_iterator(get<ObjectImpl>().erase(it.base()));
589 inline dynamic::const_key_iterator dynamic::erase(const_key_iterator first,
590 const_key_iterator last) {
591 return const_key_iterator(get<ObjectImpl>().erase(first.base(),
595 inline dynamic::const_value_iterator dynamic::erase(const_value_iterator it) {
596 return const_value_iterator(get<ObjectImpl>().erase(it.base()));
599 inline dynamic::const_value_iterator dynamic::erase(const_value_iterator first,
600 const_value_iterator last) {
601 return const_value_iterator(get<ObjectImpl>().erase(first.base(),
605 inline dynamic::const_item_iterator dynamic::erase(const_item_iterator it) {
606 return const_item_iterator(get<ObjectImpl>().erase(it.base()));
609 inline dynamic::const_item_iterator dynamic::erase(const_item_iterator first,
610 const_item_iterator last) {
611 return const_item_iterator(get<ObjectImpl>().erase(first.base(),
615 inline void dynamic::resize(std::size_t sz, dynamic const& c) {
616 auto& arr = get<Array>();
620 inline void dynamic::push_back(dynamic const& v) {
621 auto& arr = get<Array>();
625 inline void dynamic::push_back(dynamic&& v) {
626 auto& arr = get<Array>();
627 arr.push_back(std::move(v));
630 inline void dynamic::pop_back() {
631 auto& arr = get<Array>();
635 //////////////////////////////////////////////////////////////////////
637 inline dynamic::dynamic(Array&& r) : type_(ARRAY) {
638 new (&u_.array) Array(std::move(r));
641 #define FOLLY_DYNAMIC_DEC_TYPEINFO(T, str, val) \
642 template <> struct dynamic::TypeInfo<T> { \
643 static constexpr const char* name = str; \
644 static constexpr dynamic::Type type = val; \
648 FOLLY_DYNAMIC_DEC_TYPEINFO(void*, "null", dynamic::NULLT)
649 FOLLY_DYNAMIC_DEC_TYPEINFO(bool, "boolean", dynamic::BOOL)
650 FOLLY_DYNAMIC_DEC_TYPEINFO(std::string, "string", dynamic::STRING)
651 FOLLY_DYNAMIC_DEC_TYPEINFO(dynamic::Array, "array", dynamic::ARRAY)
652 FOLLY_DYNAMIC_DEC_TYPEINFO(double, "double", dynamic::DOUBLE)
653 FOLLY_DYNAMIC_DEC_TYPEINFO(int64_t, "int64", dynamic::INT64)
654 FOLLY_DYNAMIC_DEC_TYPEINFO(dynamic::ObjectImpl, "object", dynamic::OBJECT)
656 #undef FOLLY_DYNAMIC_DEC_TYPEINFO
659 T dynamic::asImpl() const {
661 case INT64: return to<T>(*get_nothrow<int64_t>());
662 case DOUBLE: return to<T>(*get_nothrow<double>());
663 case BOOL: return to<T>(*get_nothrow<bool>());
665 return to<T>(*get_nothrow<std::string>());
667 throw TypeError("int/double/bool/string", type());
671 // Return a T* to our type, or null if we're not that type.
673 T* dynamic::get_nothrow() & noexcept {
674 if (type_ != TypeInfo<T>::type) {
677 return getAddress<T>();
681 T const* dynamic::get_nothrow() const& noexcept {
682 return const_cast<dynamic*>(this)->get_nothrow<T>();
685 // Return T* for where we can put a T, without type checking. (Memory
686 // might be uninitialized, even.)
688 T* dynamic::getAddress() noexcept {
689 return GetAddrImpl<T>::get(u_);
693 T const* dynamic::getAddress() const noexcept {
694 return const_cast<dynamic*>(this)->getAddress<T>();
697 template<class T> struct dynamic::GetAddrImpl {};
698 template<> struct dynamic::GetAddrImpl<void*> {
699 static void** get(Data& d) noexcept { return &d.nul; }
701 template<> struct dynamic::GetAddrImpl<dynamic::Array> {
702 static Array* get(Data& d) noexcept { return &d.array; }
704 template<> struct dynamic::GetAddrImpl<bool> {
705 static bool* get(Data& d) noexcept { return &d.boolean; }
707 template<> struct dynamic::GetAddrImpl<int64_t> {
708 static int64_t* get(Data& d) noexcept { return &d.integer; }
710 template<> struct dynamic::GetAddrImpl<double> {
711 static double* get(Data& d) noexcept { return &d.doubl; }
714 struct dynamic::GetAddrImpl<std::string> {
715 static std::string* get(Data& d) noexcept {
719 template<> struct dynamic::GetAddrImpl<dynamic::ObjectImpl> {
720 static_assert(sizeof(ObjectImpl) <= sizeof(Data::objectBuffer),
721 "In your implementation, std::unordered_map<> apparently takes different"
722 " amount of space depending on its template parameters. This is "
723 "weird. Make objectBuffer bigger if you want to compile dynamic.");
725 static ObjectImpl* get(Data& d) noexcept {
726 void* data = &d.objectBuffer;
727 return static_cast<ObjectImpl*>(data);
733 if (auto* p = get_nothrow<T>()) {
736 throw TypeError(TypeInfo<T>::name, type());
740 T const& dynamic::get() const {
741 return const_cast<dynamic*>(this)->get<T>();
744 //////////////////////////////////////////////////////////////////////
747 * Helper for implementing operator<<. Throws if the type shouldn't
751 struct dynamic::PrintImpl {
752 static void print(dynamic const&, std::ostream& out, T const& t) {
756 // Otherwise, null, being (void*)0, would print as 0.
758 struct dynamic::PrintImpl<void*> {
759 static void print(dynamic const& /* d */,
762 DCHECK_EQ((void*)0, nul);
767 struct dynamic::PrintImpl<dynamic::ObjectImpl> {
768 static void print(dynamic const& d,
770 dynamic::ObjectImpl const&) {
771 d.print_as_pseudo_json(out);
775 struct dynamic::PrintImpl<dynamic::Array> {
776 static void print(dynamic const& d,
778 dynamic::Array const&) {
779 d.print_as_pseudo_json(out);
783 inline void dynamic::print(std::ostream& out) const {
784 #define FB_X(T) PrintImpl<T>::print(*this, out, *getAddress<T>())
785 FB_DYNAMIC_APPLY(type_, FB_X);
789 inline std::ostream& operator<<(std::ostream& out, dynamic const& d) {
794 //////////////////////////////////////////////////////////////////////
796 // Secialization of FormatValue so dynamic objects can be formatted
798 class FormatValue<dynamic> {
800 explicit FormatValue(const dynamic& val) : val_(val) { }
802 template <class FormatCallback>
803 void format(FormatArg& arg, FormatCallback& cb) const {
804 switch (val_.type()) {
806 FormatValue<std::nullptr_t>(nullptr).format(arg, cb);
809 FormatValue<bool>(val_.asBool()).format(arg, cb);
812 FormatValue<int64_t>(val_.asInt()).format(arg, cb);
814 case dynamic::STRING:
815 FormatValue<std::string>(val_.asString()).format(arg, cb);
817 case dynamic::DOUBLE:
818 FormatValue<double>(val_.asDouble()).format(arg, cb);
821 FormatValue(val_.at(arg.splitIntKey())).format(arg, cb);
823 case dynamic::OBJECT:
824 FormatValue(val_.at(arg.splitKey().toString())).format(arg, cb);
834 class FormatValue<detail::DefaultValueWrapper<dynamic, V>> {
836 explicit FormatValue(
837 const detail::DefaultValueWrapper<dynamic, V>& val)
840 template <class FormatCallback>
841 void format(FormatArg& arg, FormatCallback& cb) const {
842 auto& c = val_.container;
847 case dynamic::STRING:
848 case dynamic::DOUBLE:
849 FormatValue<dynamic>(c).format(arg, cb);
853 int key = arg.splitIntKey();
854 if (key >= 0 && size_t(key) < c.size()) {
855 FormatValue<dynamic>(c.at(key)).format(arg, cb);
857 FormatValue<V>(val_.defaultValue).format(arg, cb);
861 case dynamic::OBJECT:
863 auto pos = c.find(arg.splitKey());
864 if (pos != c.items().end()) {
865 FormatValue<dynamic>(pos->second).format(arg, cb);
867 FormatValue<V>(val_.defaultValue).format(arg, cb);
875 const detail::DefaultValueWrapper<dynamic, V>& val_;
880 #undef FB_DYNAMIC_APPLY