diff options
Diffstat (limited to 'indra/llcommon/llsdutil.h')
| -rw-r--r-- | indra/llcommon/llsdutil.h | 132 |
1 files changed, 124 insertions, 8 deletions
diff --git a/indra/llcommon/llsdutil.h b/indra/llcommon/llsdutil.h index 38bbe19ddd..3ce0b1726d 100644 --- a/indra/llcommon/llsdutil.h +++ b/indra/llcommon/llsdutil.h @@ -365,15 +365,14 @@ private: // subject function has returned, so we must ensure that any constructed // LLSDParam<T> lives just as long as this LLSDParam<LLSD> does. Putting // each LLSDParam<T> on the heap and capturing a smart pointer in a vector - // works. We would have liked to use std::unique_ptr, but vector entries - // must be copyable. + // works. // (Alternatively we could assume that every instance of LLSDParam<LLSD> // will be asked for at most ONE conversion. We could store a scalar // std::unique_ptr and, when constructing an new LLSDParam<T>, assert that // the unique_ptr is empty. But some future change in usage patterns, and // consequent failure of that assertion, would be very mysterious. Instead // of explaining how to fix it, just fix it now.) - mutable std::vector<std::shared_ptr<LLSDParamBase>> converters_; + mutable std::vector<std::unique_ptr<LLSDParamBase>> converters_; public: LLSDParam(const LLSD& value): value_(value) {} @@ -389,9 +388,9 @@ public: { // capture 'ptr' with the specific subclass type because converters_ // only stores LLSDParamBase pointers - auto ptr{ std::make_shared<LLSDParam<std::decay_t<T>>>(value_) }; + auto ptr{ new LLSDParam<std::decay_t<T>>(value_) }; // keep the new converter alive until we ourselves are destroyed - converters_.push_back(ptr); + converters_.emplace_back(ptr); return *ptr; } }; @@ -474,12 +473,12 @@ public: } }; -namespace llsd -{ - /***************************************************************************** * range-based for-loop helpers for LLSD *****************************************************************************/ +namespace llsd +{ + /// Usage: for (LLSD item : inArray(someLLSDarray)) { ... } class inArray { @@ -525,7 +524,70 @@ private: } // namespace llsd +/***************************************************************************** +* LLSDParam<std::vector<T>> +*****************************************************************************/ +// Given an LLSD array, return a const std::vector<T>&, where T is a type +// supported by LLSDParam. Bonus: if the LLSD value is actually a scalar, +// return a single-element vector containing the converted value. +template <typename T> +class LLSDParam<std::vector<T>>: public LLSDParamBase +{ +public: + LLSDParam(const LLSD& array) + { + // treat undefined "array" as empty vector + if (array.isDefined()) + { + // what if it's a scalar? + if (! array.isArray()) + { + v.push_back(LLSDParam<T>(array)); + } + else // really is an array + { + // reserve space for the array entries + v.reserve(array.size()); + for (const auto& item : llsd::inArray(array)) + { + v.push_back(LLSDParam<T>(item)); + } + } + } + } + + operator const std::vector<T>&() const { return v; } + +private: + std::vector<T> v; +}; + +/***************************************************************************** +* LLSDParam<std::map<std::string, T>> +*****************************************************************************/ +// Given an LLSD map, return a const std::map<std::string, T>&, where T is a +// type supported by LLSDParam. +template <typename T> +class LLSDParam<std::map<std::string, T>>: public LLSDParamBase +{ +public: + LLSDParam(const LLSD& map) + { + for (const auto& pair : llsd::inMap(map)) + { + m[pair.first] = LLSDParam<T>(pair.second); + } + } + + operator const std::map<std::string, T>&() const { return m; } + +private: + std::map<std::string, T> m; +}; +/***************************************************************************** +* deep and shallow clone +*****************************************************************************/ // Creates a deep clone of an LLSD object. Maps, Arrays and binary objects // are duplicated, atomic primitives (Boolean, Integer, Real, etc) simply // use a shared reference. @@ -553,6 +615,60 @@ LLSD shallow(LLSD value, LLSD filter=LLSD()) { return llsd_shallow(value, filter } // namespace llsd +/***************************************************************************** +* toArray(), toMap() +*****************************************************************************/ +namespace llsd +{ + +// For some T convertible to LLSD, given std::vector<T> myVec, +// toArray(myVec) returns an LLSD array whose entries correspond to the +// items in myVec. +// For some U convertible to LLSD, given function U xform(const T&), +// toArray(myVec, xform) returns an LLSD array whose every entry is +// xform(item) of the corresponding item in myVec. +// toArray() actually works with any container<C> usable with range +// 'for', not just std::vector. +// (Once we get C++20 we can use std::identity instead of this default lambda.) +template <typename C, typename FUNC> +LLSD toArray(const C& container, FUNC&& func=[](const auto& arg){ return arg; }) +{ + LLSD array; + for (const auto& item : container) + { + array.append(std::forward<FUNC>(func)(item)); + } + return array; +} + +// For some T convertible to LLSD, given std::map<std::string, T> myMap, +// toMap(myMap) returns an LLSD map whose entries correspond to the +// (key, value) pairs in myMap. +// For some U convertible to LLSD, given function +// std::pair<std::string, U> xform(const std::pair<std::string, T>&), +// toMap(myMap, xform) returns an LLSD map whose every entry is +// xform(pair) of the corresponding (key, value) pair in myMap. +// toMap() actually works with any container usable with range 'for', not +// just std::map. It need not even be an associative container, as long as +// you pass an xform function that returns std::pair<std::string, U>. +// (Once we get C++20 we can use std::identity instead of this default lambda.) +template <typename C, typename FUNC> +LLSD toMap(const C& container, FUNC&& func=[](const auto& arg){ return arg; }) +{ + LLSD map; + for (const auto& pair : container) + { + const auto& [key, value] = std::forward<FUNC>(func)(pair); + map[key] = value; + } + return map; +} + +} // namespace llsd + +/***************************************************************************** +* boost::hash<LLSD> +*****************************************************************************/ // Specialization for generating a hash value from an LLSD block. namespace boost { |