Convert .tgs with go libraries (and cgo) (telegram) (#1569)

This commit adds support for go/cgo tgs conversion when building with the -tags `cgo`
The default binaries are still "pure" go and uses the old way of converting.

* Move lottie_convert.py conversion code to its own file

* Add optional libtgsconverter

* Update vendor

* Apply suggestions from code review

* Update bridge/helper/libtgsconverter.go

Co-authored-by: Wim <wim@42.be>

1 files changed, 121 insertions, 0 deletions

diff --git a/vendor/github.com/Benau/go_rlottie/lottie_rapidjson_stringbuffer.h b/vendor/github.com/Benau/go_rlottie/lottie_rapidjson_stringbuffer.h
new file mode 100644
index 00000000..295d6a2f
--- /dev/null
+++ b/vendor/github.com/Benau/go_rlottie/lottie_rapidjson_stringbuffer.h
@@ -0,0 +1,121 @@
+// Tencent is pleased to support the open source community by making RapidJSON available.
+// 
+// Copyright (C) 2015 THL A29 Limited, a Tencent company, and Milo Yip. All rights reserved.
+//
+// Licensed under the MIT License (the "License"); you may not use this file except
+// in compliance with the License. You may obtain a copy of the License at
+//
+// http://opensource.org/licenses/MIT
+//
+// Unless required by applicable law or agreed to in writing, software distributed 
+// under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR 
+// CONDITIONS OF ANY KIND, either express or implied. See the License for the 
+// specific language governing permissions and limitations under the License.
+
+#ifndef RAPIDJSON_STRINGBUFFER_H_
+#define RAPIDJSON_STRINGBUFFER_H_
+
+#include "lottie_rapidjson_stream.h"
+#include "lottie_rapidjson_internal_stack.h"
+
+#if RAPIDJSON_HAS_CXX11_RVALUE_REFS
+#include <utility> // std::move
+#endif
+
+#include "lottie_rapidjson_internal_stack.h"
+
+#if defined(__clang__)
+RAPIDJSON_DIAG_PUSH
+RAPIDJSON_DIAG_OFF(c++98-compat)
+#endif
+
+RAPIDJSON_NAMESPACE_BEGIN
+
+//! Represents an in-memory output stream.
+/*!
+    \tparam Encoding Encoding of the stream.
+    \tparam Allocator type for allocating memory buffer.
+    \note implements Stream concept
+*/
+template <typename Encoding, typename Allocator = CrtAllocator>
+class GenericStringBuffer {
+public:
+    typedef typename Encoding::Ch Ch;
+
+    GenericStringBuffer(Allocator* allocator = 0, size_t capacity = kDefaultCapacity) : stack_(allocator, capacity) {}
+
+#if RAPIDJSON_HAS_CXX11_RVALUE_REFS
+    GenericStringBuffer(GenericStringBuffer&& rhs) : stack_(std::move(rhs.stack_)) {}
+    GenericStringBuffer& operator=(GenericStringBuffer&& rhs) {
+        if (&rhs != this)
+            stack_ = std::move(rhs.stack_);
+        return *this;
+    }
+#endif
+
+    void Put(Ch c) { *stack_.template Push<Ch>() = c; }
+    void PutUnsafe(Ch c) { *stack_.template PushUnsafe<Ch>() = c; }
+    void Flush() {}
+
+    void Clear() { stack_.Clear(); }
+    void ShrinkToFit() {
+        // Push and pop a null terminator. This is safe.
+        *stack_.template Push<Ch>() = '\0';
+        stack_.ShrinkToFit();
+        stack_.template Pop<Ch>(1);
+    }
+
+    void Reserve(size_t count) { stack_.template Reserve<Ch>(count); }
+    Ch* Push(size_t count) { return stack_.template Push<Ch>(count); }
+    Ch* PushUnsafe(size_t count) { return stack_.template PushUnsafe<Ch>(count); }
+    void Pop(size_t count) { stack_.template Pop<Ch>(count); }
+
+    const Ch* GetString() const {
+        // Push and pop a null terminator. This is safe.
+        *stack_.template Push<Ch>() = '\0';
+        stack_.template Pop<Ch>(1);
+
+        return stack_.template Bottom<Ch>();
+    }
+
+    //! Get the size of string in bytes in the string buffer.
+    size_t GetSize() const { return stack_.GetSize(); }
+
+    //! Get the length of string in Ch in the string buffer.
+    size_t GetLength() const { return stack_.GetSize() / sizeof(Ch); }
+
+    static const size_t kDefaultCapacity = 256;
+    mutable internal::Stack<Allocator> stack_;
+
+private:
+    // Prohibit copy constructor & assignment operator.
+    GenericStringBuffer(const GenericStringBuffer&);
+    GenericStringBuffer& operator=(const GenericStringBuffer&);
+};
+
+//! String buffer with UTF8 encoding
+typedef GenericStringBuffer<UTF8<> > StringBuffer;
+
+template<typename Encoding, typename Allocator>
+inline void PutReserve(GenericStringBuffer<Encoding, Allocator>& stream, size_t count) {
+    stream.Reserve(count);
+}
+
+template<typename Encoding, typename Allocator>
+inline void PutUnsafe(GenericStringBuffer<Encoding, Allocator>& stream, typename Encoding::Ch c) {
+    stream.PutUnsafe(c);
+}
+
+//! Implement specialized version of PutN() with memset() for better performance.
+template<>
+inline void PutN(GenericStringBuffer<UTF8<> >& stream, char c, size_t n) {
+    std::memset(stream.stack_.Push<char>(n), c, n * sizeof(c));
+}
+
+RAPIDJSON_NAMESPACE_END
+
+#if defined(__clang__)
+RAPIDJSON_DIAG_POP
+#endif
+
+#endif // RAPIDJSON_STRINGBUFFER_H_