src/dawn/node/utils/Debug.h

// Copyright 2021 The Dawn & Tint Authors
//
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// modification, are permitted provided that the following conditions are met:
//
// 1. Redistributions of source code must retain the above copyright notice, this
//    list of conditions and the following disclaimer.
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// 2. 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.
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// 3. Neither the name of the copyright holder nor the names of its
//    contributors may be used to endorse or promote products derived from
//    this software without specific prior written permission.
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// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
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#ifndef SRC_DAWN_NODE_UTILS_DEBUG_H_
#define SRC_DAWN_NODE_UTILS_DEBUG_H_

#include <iostream>
#include <optional>
#include <sstream>
#include <unordered_map>
#include <utility>
#include <variant>
#include <vector>

#include "dawn/webgpu_cpp_print.h"

namespace wgpu::utils {

// Write() is a helper for printing container types to the std::ostream.
// Write() is used by the LOG() macro below.

// Forward declarations
inline std::ostream& Write(std::ostream& out) {
    return out;
}
template <typename T>
inline std::ostream& Write(std::ostream& out, const std::optional<T>& value);
template <typename T>
inline std::ostream& Write(std::ostream& out, const std::vector<T>& value);
template <typename K, typename V>
inline std::ostream& Write(std::ostream& out, const std::unordered_map<K, V>& value);
template <typename... TYS>
inline std::ostream& Write(std::ostream& out, const std::variant<TYS...>& value);
template <typename VALUE>
std::ostream& Write(std::ostream& out, VALUE&& value);

// Write() implementations
template <typename T>
std::ostream& Write(std::ostream& out, const std::optional<T>& value) {
    if (value.has_value()) {
        return Write(out, value.value());
    }
    return out << "<undefined>";
}

template <typename T>
std::ostream& Write(std::ostream& out, const std::vector<T>& value) {
    out << "[";
    bool first = true;
    for (const auto& el : value) {
        if (!first) {
            out << ", ";
        }
        first = false;
        Write(out, el);
    }
    return out << "]";
}

template <typename K, typename V>
std::ostream& Write(std::ostream& out, const std::unordered_map<K, V>& value) {
    out << "{";
    bool first = true;
    for (auto& [key, value] : value) {
        if (!first) {
            out << ", ";
        }
        first = false;
        Write(out, key);
        out << ": ";
        Write(out, value);
    }
    return out << "}";
}

template <typename... TYS>
std::ostream& Write(std::ostream& out, const std::variant<TYS...>& value) {
    std::visit([&](auto&& v) { Write(out, v); }, value);
    return out;
}

template <typename VALUE>
std::ostream& Write(std::ostream& out, VALUE&& value) {
    return out << std::forward<VALUE>(value);
}

template <typename FIRST, typename... REST>
inline std::ostream& Write(std::ostream& out, FIRST&& first, REST&&... rest) {
    Write(out, std::forward<FIRST>(first));
    Write(out, std::forward<REST>(rest)...);
    return out;
}

// Fatal() prints a message to stdout with the given file, line, function and optional message,
// then calls abort(). Fatal() is usually not called directly, but by the UNREACHABLE() and
// UNIMPLEMENTED() macro below.
template <typename... MSG_ARGS>
[[noreturn]] inline void Fatal(const char* reason,
                               const char* file,
                               int line,
                               const char* function,
                               MSG_ARGS&&... msg_args) {
    std::stringstream msg;
    msg << file << ":" << line << ": " << reason << ": " << function << "()";
    if constexpr (sizeof...(msg_args) > 0) {
        msg << " ";
        Write(msg, std::forward<MSG_ARGS>(msg_args)...);
    }
    std::cout << msg.str() << std::endl;
    abort();
}

// LOG() prints the current file, line and function to stdout, followed by a
// string representation of all the variadic arguments.
#define LOG(...)                                                                                  \
    ::wgpu::utils::Write(std::cout << __FILE__ << ":" << __LINE__ << " " << __FUNCTION__ << ": ", \
                         ##__VA_ARGS__)                                                           \
        << std::endl

// UNIMPLEMENTED(env) raises a JS exception. Used to stub code that has not yet been implemented.
#define UNIMPLEMENTED(env, ...)                                              \
    do {                                                                     \
        Napi::Error::New(env, "UNIMPLEMENTED").ThrowAsJavaScriptException(); \
        return __VA_ARGS__;                                                  \
    } while (false)

// UNREACHABLE() prints 'UNREACHABLE' with the current file, line and
// function to stdout, along with the optional message, then calls abort().
// The macro calls Fatal(), which is annotated with [[noreturn]].
// Used to stub code that has not yet been implemented.
#define UNREACHABLE(...) \
    ::wgpu::utils::Fatal("UNREACHABLE", __FILE__, __LINE__, __FUNCTION__, ##__VA_ARGS__)

}  // namespace wgpu::utils

#endif  // SRC_DAWN_NODE_UTILS_DEBUG_H_