// If async mode is enabled, this call blocks till all currently pending ops are
// done.
TF_CAPI_EXPORT extern void TFE_ContextExportRunMetadata(TFE_Context* ctx,
                                                        TF_Buffer* buf,
                                                        TF_Status* status);

// Some TF ops need a step container to be set to limit the lifetime of some

struct TFStatusDeleter {
  void operator()(TF_Status* s) const { TF_DeleteStatus(s); }
};
using OwnedTFStatus = std::unique_ptr<TF_Status, TFStatusDeleter>;

struct TFBufferDeleter {
  void operator()(TF_Buffer* buf) const { TF_DeleteBuffer(buf); }
};
using OwnedTFBuffer = std::unique_ptr<TF_Buffer, TFBufferDeleter>;

class CGraphOptimizer : public CustomGraphOptimizer {
 public:

// Serialize `attrs` as a tensorflow::NameAttrList protocol buffer (into `buf`),
// containing the op name and a map of its attributes.
TF_CAPI_EXPORT extern void TFE_OpAttrsSerialize(const TFE_OpAttrs* attrs,
                                                TF_Buffer* buf,
                                                TF_Status* status);

typedef struct TF_FunctionLibraryDefinition TF_FunctionLibraryDefinition;

// Create NewFunctionLibraryDefinition.
TF_CAPI_EXPORT extern TF_FunctionLibraryDefinition*
TF_NewFunctionLibraryDefinition(const TF_Buffer* graph_buf, TF_Status* status);

// Delete NewFunctionLibraryDefinition.
TF_CAPI_EXPORT extern void TF_DeleteFunctionLibraryDefinition(
    TF_FunctionLibraryDefinition* fn_lib);

// inside the `TF_Filesystem_Option_Value` struct)
// as MSVC does not recognize `typeof`.
typedef union TF_Filesystem_Option_Value_Union {
  int64_t int_val;
  double real_val;
  struct {
    char* buf;
    int buf_length;
  } buffer_val;
} TF_Filesystem_Option_Value_Union;

typedef struct TF_Filesystem_Option_Value {
  int type_tag;    // type of values in the values union
  int num_values;  // number of values