/* Copyright 2017 The TensorFlow Authors. All Rights Reserved.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

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 TENSORFLOW_LITE_CORE_API_ERROR_REPORTER_H_
#define TENSORFLOW_LITE_CORE_API_ERROR_REPORTER_H_

#include <cstdarg>

namespace tflite {

/// A functor that reports error to supporting system. Invoked similar to
/// printf.
///
/// Usage:
///  ErrorReporter foo;
///  foo.Report("test %d", 5);
/// or
///  va_list args;
///  foo.Report("test %d", args); // where args is va_list
///
/// Subclass ErrorReporter to provide another reporting destination.
/// For example, if you have a GUI program, you might redirect to a buffer
/// that drives a GUI error log box.
class ErrorReporter {
 public:
  virtual ~ErrorReporter() = default;
  /// Converts `args` to character equivalents according to `format` string,
  /// constructs the error string and report it.
  /// Returns number of characters written or zero on success, and negative
  /// number on error.
  virtual int Report(const char* format, va_list args) = 0;

  /// Converts arguments to character equivalents according to `format` string,
  /// constructs the error string and report it.
  /// Returns number of characters written or zero on success, and negative
  /// number on error.
  int Report(const char* format, ...);

  /// Equivalent to `Report` above. The additional `void*` parameter is unused.
  /// This method is for compatibility with macros that takes `TfLiteContext`,
  /// like TF_LITE_ENSURE and related macros.
  int ReportError(void*, const char* format, ...);
};

}  // namespace tflite

// You should not make bare calls to the error reporter, instead use the
// TF_LITE_REPORT_ERROR macro, since this allows message strings to be
// stripped when the binary size has to be optimized. If you are looking to
// reduce binary size, define TF_LITE_STRIP_ERROR_STRINGS when compiling and
// every call will be stubbed out, taking no memory.
#ifndef TF_LITE_STRIP_ERROR_STRINGS
#define TF_LITE_REPORT_ERROR(reporter, ...)                             \
  do {                                                                  \
    static_cast<tflite::ErrorReporter*>(reporter)->Report(__VA_ARGS__); \
  } while (false)
#else  // TF_LITE_STRIP_ERROR_STRINGS
#define TF_LITE_REPORT_ERROR(reporter, ...)
#endif  // TF_LITE_STRIP_ERROR_STRINGS

#endif  // TENSORFLOW_LITE_CORE_API_ERROR_REPORTER_H_
