| /* |
| * Copyright 2019 Google LLC |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #ifndef WasmCommon_DEFINED |
| #define WasmCommon_DEFINED |
| |
| #include <emscripten.h> |
| #include <emscripten/bind.h> |
| #include "include/core/SkColor.h" |
| #include "include/core/SkSpan.h" |
| #include "include/private/base/SkMalloc.h" |
| |
| using namespace emscripten; |
| |
| // Self-documenting types |
| using JSColor = int32_t; |
| using JSArray = emscripten::val; |
| using JSObject = emscripten::val; |
| using JSString = emscripten::val; |
| using SkPathOrNull = emscripten::val; |
| using TypedArray = emscripten::val; |
| using Uint8Array = emscripten::val; |
| using Uint16Array = emscripten::val; |
| using Uint32Array = emscripten::val; |
| using Float32Array = emscripten::val; |
| |
| // If we are using C++ and EMSCRIPTEN_BINDINGS, we can't have primitive pointers in our function |
| // type signatures. (this gives an error message like "Cannot call foo due to unbound |
| // types Pi, Pf"). But, we can just pretend they are numbers and cast them to be pointers and |
| // the compiler is happy. |
| // These types refer to the TypedArray that the JS interface wrote into or will read out of. |
| // This doesn't stop us from using these as different types; e.g. a float* can be treated as an |
| // SkPoint* in some APIs. |
| using WASMPointerF32 = uintptr_t; |
| using WASMPointerI32 = uintptr_t; |
| using WASMPointerU8 = uintptr_t; |
| using WASMPointerU16 = uintptr_t; |
| using WASMPointerU32 = uintptr_t; |
| using WASMPointer = uintptr_t; |
| |
| #define SPECIALIZE_JSARRAYTYPE(type, name) \ |
| template <> struct JSArrayType<type> { \ |
| static constexpr const char* const gName = name; \ |
| } |
| |
| template <typename T> struct JSArrayType {}; |
| |
| SPECIALIZE_JSARRAYTYPE( int8_t, "Int8Array"); |
| SPECIALIZE_JSARRAYTYPE(uint8_t, "Uint8Array"); |
| SPECIALIZE_JSARRAYTYPE( int16_t, "Int16Array"); |
| SPECIALIZE_JSARRAYTYPE(uint16_t, "Uint16Array"); |
| SPECIALIZE_JSARRAYTYPE( int32_t, "Int32Array"); |
| SPECIALIZE_JSARRAYTYPE(uint32_t, "Uint32Array"); |
| SPECIALIZE_JSARRAYTYPE(float, "Float32Array"); |
| |
| #undef SPECIALIZE_JSARRAYTYPE |
| |
| /** |
| * Create a typed-array (in the JS heap) and initialize it with the provided |
| * data (from the wasm heap). |
| */ |
| template <typename T> TypedArray MakeTypedArray(int count, const T src[]) { |
| emscripten::val length = emscripten::val(count); |
| emscripten::val jarray = emscripten::val::global(JSArrayType<T>::gName).new_(count); |
| jarray.call<void>("set", val(typed_memory_view(count, src))); |
| return jarray; |
| } |
| |
| /** |
| * Gives read access to a JSArray |
| * |
| * We explicitly use malloc/free (not new/delete) so this can be used with allocations from the JS |
| * side (ala CanvasKit.Malloc). |
| */ |
| template <typename T> class JSSpan { |
| public: |
| // Note: Use of this constructor is 5-20x slower than manually copying the data on the JS side |
| // and sending over a pointer, length, and boolean for the other constructor. |
| JSSpan(JSArray src) { |
| const size_t len = src["length"].as<size_t>(); |
| T* data; |
| |
| // If the buffer was allocated via CanvasKit' Malloc, we can peek directly at it! |
| if (src["_ck"].isTrue()) { |
| fOwned = false; |
| data = reinterpret_cast<T*>(src["byteOffset"].as<size_t>()); |
| } else { |
| fOwned = true; |
| data = static_cast<T*>(sk_malloc_throw(len, sizeof(T))); |
| |
| // now actually copy into 'data' |
| if (src.instanceof(emscripten::val::global(JSArrayType<T>::gName))) { |
| auto dst_view = emscripten::val(typed_memory_view(len, data)); |
| dst_view.call<void>("set", src); |
| } else { |
| for (size_t i = 0; i < len; ++i) { |
| data[i] = src[i].as<T>(); |
| } |
| } |
| } |
| fSpan = SkSpan(data, len); |
| } |
| |
| JSSpan(WASMPointer ptr, size_t len, bool takeOwnership): fOwned(takeOwnership) { |
| fSpan = SkSpan(reinterpret_cast<T*>(ptr), len); |
| } |
| |
| ~JSSpan() { |
| if (fOwned) { |
| sk_free(fSpan.data()); |
| } |
| } |
| |
| const T* data() const { return fSpan.data(); } |
| size_t size() const { return fSpan.size(); } |
| |
| private: |
| SkSpan<T> fSpan; |
| bool fOwned; |
| }; |
| |
| #endif |