add external dependencies in a pre-built way to avoid incompatibilities

external/include/google/protobuf/metadata_lite.h

@@ -0,0 +1,270 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#ifndef GOOGLE_PROTOBUF_METADATA_LITE_H__
+#define GOOGLE_PROTOBUF_METADATA_LITE_H__
+
+#include <string>
+#include <google/protobuf/stubs/common.h>
+#include <google/protobuf/arena.h>
+#include <google/protobuf/port.h>
+
+#include <google/protobuf/port_def.inc>
+
+#ifdef SWIG
+#error "You cannot SWIG proto headers"
+#endif
+
+namespace google {
+namespace protobuf {
+namespace internal {
+
+// This is the representation for messages that support arena allocation. It
+// uses a tagged pointer to either store the owning Arena pointer, if there are
+// no unknown fields, or a pointer to a block of memory with both the owning
+// Arena pointer and the UnknownFieldSet, if there are unknown fields. Besides,
+// it also uses the tag to distinguish whether the owning Arena pointer is also
+// used by sub-structure allocation. This optimization allows for
+// "zero-overhead" storage of the Arena pointer, relative to the above baseline
+// implementation.
+//
+// The tagged pointer uses the least two significant bits to disambiguate cases.
+// It uses bit 0 == 0 to indicate an arena pointer and bit 0 == 1 to indicate a
+// UFS+Arena-container pointer. Besides it uses bit 1 == 0 to indicate arena
+// allocation and bit 1 == 1 to indicate heap allocation.
+class InternalMetadata {
+ public:
+  constexpr InternalMetadata() : ptr_(0) {}
+  explicit InternalMetadata(Arena* arena, bool is_message_owned = false)
+      : ptr_(is_message_owned
+                 ? reinterpret_cast<intptr_t>(arena) | kMessageOwnedArenaTagMask
+                 : reinterpret_cast<intptr_t>(arena)) {
+    GOOGLE_DCHECK(!is_message_owned || arena != nullptr);
+  }
+
+  ~InternalMetadata() {
+    if (HasMessageOwnedArenaTag()) {
+      delete arena();
+    }
+  }
+
+  template <typename T>
+  void Delete() {
+    // Note that Delete<> should be called not more than once.
+    if (have_unknown_fields()) {
+      DeleteOutOfLineHelper<T>();
+    }
+  }
+
+  PROTOBUF_NDEBUG_INLINE Arena* owning_arena() const {
+    return HasMessageOwnedArenaTag() ? nullptr : arena();
+  }
+
+  PROTOBUF_NDEBUG_INLINE Arena* arena() const {
+    if (PROTOBUF_PREDICT_FALSE(have_unknown_fields())) {
+      return PtrValue<ContainerBase>()->arena;
+    } else {
+      return PtrValue<Arena>();
+    }
+  }
+
+  PROTOBUF_NDEBUG_INLINE bool have_unknown_fields() const {
+    return HasUnknownFieldsTag();
+  }
+
+  PROTOBUF_NDEBUG_INLINE void* raw_arena_ptr() const {
+    return reinterpret_cast<void*>(ptr_);
+  }
+
+  template <typename T>
+  PROTOBUF_NDEBUG_INLINE const T& unknown_fields(
+      const T& (*default_instance)()) const {
+    if (PROTOBUF_PREDICT_FALSE(have_unknown_fields())) {
+      return PtrValue<Container<T>>()->unknown_fields;
+    } else {
+      return default_instance();
+    }
+  }
+
+  template <typename T>
+  PROTOBUF_NDEBUG_INLINE T* mutable_unknown_fields() {
+    if (PROTOBUF_PREDICT_TRUE(have_unknown_fields())) {
+      return &PtrValue<Container<T>>()->unknown_fields;
+    } else {
+      return mutable_unknown_fields_slow<T>();
+    }
+  }
+
+  template <typename T>
+  PROTOBUF_NDEBUG_INLINE void Swap(InternalMetadata* other) {
+    // Semantics here are that we swap only the unknown fields, not the arena
+    // pointer. We cannot simply swap ptr_ with other->ptr_ because we need to
+    // maintain our own arena ptr. Also, our ptr_ and other's ptr_ may be in
+    // different states (direct arena pointer vs. container with UFS) so we
+    // cannot simply swap ptr_ and then restore the arena pointers. We reuse
+    // UFS's swap implementation instead.
+    if (have_unknown_fields() || other->have_unknown_fields()) {
+      DoSwap<T>(other->mutable_unknown_fields<T>());
+    }
+  }
+
+  PROTOBUF_NDEBUG_INLINE void InternalSwap(InternalMetadata* other) {
+    std::swap(ptr_, other->ptr_);
+  }
+
+  template <typename T>
+  PROTOBUF_NDEBUG_INLINE void MergeFrom(const InternalMetadata& other) {
+    if (other.have_unknown_fields()) {
+      DoMergeFrom<T>(other.unknown_fields<T>(nullptr));
+    }
+  }
+
+  template <typename T>
+  PROTOBUF_NDEBUG_INLINE void Clear() {
+    if (have_unknown_fields()) {
+      DoClear<T>();
+    }
+  }
+
+ private:
+  intptr_t ptr_;
+
+  // Tagged pointer implementation.
+  static constexpr intptr_t kUnknownFieldsTagMask = 1;
+  static constexpr intptr_t kMessageOwnedArenaTagMask = 2;
+  static constexpr intptr_t kPtrTagMask =
+      kUnknownFieldsTagMask | kMessageOwnedArenaTagMask;
+  static constexpr intptr_t kPtrValueMask = ~kPtrTagMask;
+
+  // Accessors for pointer tag and pointer value.
+  PROTOBUF_ALWAYS_INLINE bool HasUnknownFieldsTag() const {
+    return ptr_ & kUnknownFieldsTagMask;
+  }
+  PROTOBUF_ALWAYS_INLINE bool HasMessageOwnedArenaTag() const {
+    return ptr_ & kMessageOwnedArenaTagMask;
+  }
+
+  template <typename U>
+  U* PtrValue() const {
+    return reinterpret_cast<U*>(ptr_ & kPtrValueMask);
+  }
+
+  // If ptr_'s tag is kTagContainer, it points to an instance of this struct.
+  struct ContainerBase {
+    Arena* arena;
+  };
+
+  template <typename T>
+  struct Container : public ContainerBase {
+    T unknown_fields;
+  };
+
+  template <typename T>
+  PROTOBUF_NOINLINE void DeleteOutOfLineHelper() {
+    if (arena() == NULL) {
+      delete PtrValue<Container<T>>();
+    }
+  }
+
+  template <typename T>
+  PROTOBUF_NOINLINE T* mutable_unknown_fields_slow() {
+    Arena* my_arena = arena();
+    Container<T>* container = Arena::Create<Container<T>>(my_arena);
+    intptr_t message_owned_arena_tag = ptr_ & kMessageOwnedArenaTagMask;
+    // Two-step assignment works around a bug in clang's static analyzer:
+    // https://bugs.llvm.org/show_bug.cgi?id=34198.
+    ptr_ = reinterpret_cast<intptr_t>(container);
+    ptr_ |= kUnknownFieldsTagMask | message_owned_arena_tag;
+    container->arena = my_arena;
+    return &(container->unknown_fields);
+  }
+
+  // Templated functions.
+
+  template <typename T>
+  PROTOBUF_NOINLINE void DoClear() {
+    mutable_unknown_fields<T>()->Clear();
+  }
+
+  template <typename T>
+  PROTOBUF_NOINLINE void DoMergeFrom(const T& other) {
+    mutable_unknown_fields<T>()->MergeFrom(other);
+  }
+
+  template <typename T>
+  PROTOBUF_NOINLINE void DoSwap(T* other) {
+    mutable_unknown_fields<T>()->Swap(other);
+  }
+};
+
+// String Template specializations.
+
+template <>
+PROTOBUF_EXPORT void InternalMetadata::DoClear<std::string>();
+template <>
+PROTOBUF_EXPORT void InternalMetadata::DoMergeFrom<std::string>(
+    const std::string& other);
+template <>
+PROTOBUF_EXPORT void InternalMetadata::DoSwap<std::string>(std::string* other);
+
+// This helper RAII class is needed to efficiently parse unknown fields. We
+// should only call mutable_unknown_fields if there are actual unknown fields.
+// The obvious thing to just use a stack string and swap it at the end of
+// the parse won't work, because the destructor of StringOutputStream needs to
+// be called before we can modify the string (it check-fails). Using
+// LiteUnknownFieldSetter setter(&_internal_metadata_);
+// StringOutputStream stream(setter.buffer());
+// guarantees that the string is only swapped after stream is destroyed.
+class PROTOBUF_EXPORT LiteUnknownFieldSetter {
+ public:
+  explicit LiteUnknownFieldSetter(InternalMetadata* metadata)
+      : metadata_(metadata) {
+    if (metadata->have_unknown_fields()) {
+      buffer_.swap(*metadata->mutable_unknown_fields<std::string>());
+    }
+  }
+  ~LiteUnknownFieldSetter() {
+    if (!buffer_.empty())
+      metadata_->mutable_unknown_fields<std::string>()->swap(buffer_);
+  }
+  std::string* buffer() { return &buffer_; }
+
+ private:
+  InternalMetadata* metadata_;
+  std::string buffer_;
+};
+
+}  // namespace internal
+}  // namespace protobuf
+}  // namespace google
+
+#include <google/protobuf/port_undef.inc>
+
+#endif  // GOOGLE_PROTOBUF_METADATA_LITE_H__