src/common/utils/Log.h

/*
 * Copyright (c) 2021 Arm Limited.
 *
 * SPDX-License-Identifier: MIT
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to
 * deal in the Software without restriction, including without limitation the
 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
 * sell copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */
#ifndef SRC_COMMON_LOG_H
#define SRC_COMMON_LOG_H

#include "arm_compute/core/Error.h"
#include "arm_compute/core/utils/logging/Macros.h"
#include "utils/TypePrinter.h"

#ifdef ARM_COMPUTE_LOGGING_ENABLED
/** Create a logger
 *
 * @note It will eventually create all default loggers in don't exist
 */
#define ARM_COMPUTE_CREATE_ACL_LOGGER()                                                                                        \
    do                                                                                                                         \
    {                                                                                                                          \
        if(arm_compute::logging::LoggerRegistry::get().logger("ComputeLibrary") == nullptr)                                    \
        {                                                                                                                      \
            arm_compute::logging::LoggerRegistry::get().create_logger("ComputeLibrary", arm_compute::logging::LogLevel::INFO); \
        }                                                                                                                      \
    } while(false)
#else /* ARM_COMPUTE_LOGGING_ENABLED */
#define ARM_COMPUTE_CREATE_ACL_LOGGER()
#endif /* ARM_COMPUTE_LOGGING_ENABLED */

/** Log a message to the logger
 *
 * @param[in] log_level Logging level
 * @param[in] msg       Message to log
 */
#define ARM_COMPUTE_LOG_MSG_ACL(log_level, msg)                \
    do                                                         \
    {                                                          \
        ARM_COMPUTE_CREATE_ACL_LOGGER();                       \
        ARM_COMPUTE_LOG_MSG("ComputeLibrary", log_level, msg); \
    } while(false)

/** Log a message with format to the logger
 *
 * @param[in] log_level Logging level
 * @param[in] fmt       String format (printf style)
 * @param[in] ...       Message arguments
 */
#define ARM_COMPUTE_LOG_MSG_WITH_FORMAT_ACL(log_level, fmt, ...)                        \
    do                                                                                  \
    {                                                                                   \
        ARM_COMPUTE_CREATE_ACL_LOGGER();                                                \
        ARM_COMPUTE_LOG_MSG_WITH_FORMAT("ComputeLibrary", log_level, fmt, __VA_ARGS__); \
    } while(false)

/** Log an error message to the logger
 *
 * @param[in] msg Message to log
 */
#define ARM_COMPUTE_LOG_ERROR_ACL(msg)                                                     \
    do                                                                                     \
    {                                                                                      \
        ARM_COMPUTE_CREATE_ACL_LOGGER();                                                   \
        ARM_COMPUTE_LOG_MSG("ComputeLibrary", arm_compute::logging::LogLevel::ERROR, msg); \
    } while(false)

/** Log an error message to the logger with function name before the message
 *
 * @param[in] msg Message to log
 */
#define ARM_COMPUTE_LOG_ERROR_WITH_FUNCNAME_ACL(msg)                                                     \
    do                                                                                                   \
    {                                                                                                    \
        ARM_COMPUTE_CREATE_ACL_LOGGER();                                                                 \
        ARM_COMPUTE_LOG_MSG_WITH_FUNCNAME("ComputeLibrary", arm_compute::logging::LogLevel::ERROR, msg); \
    } while(false)

/** Log an information message to the logger with function name before the message
 *
 * @param[in] msg Message to log
 */
#define ARM_COMPUTE_LOG_INFO_WITH_FUNCNAME_ACL(msg)                                                     \
    do                                                                                                  \
    {                                                                                                   \
        ARM_COMPUTE_CREATE_ACL_LOGGER();                                                                \
        ARM_COMPUTE_LOG_MSG_WITH_FUNCNAME("ComputeLibrary", arm_compute::logging::LogLevel::INFO, msg); \
    } while(false)

/** Function template specialization for the out of bound element at index = tuple_size
 *
 * @param[in,out] data_registry   Reference to the input parameters data in a string format
 * @param[in]     in_params_tuple Tuple of different input data types
 */
template <std::size_t Index, typename... Tp>
inline typename std::enable_if<Index == sizeof...(Tp), void>::type
logParamsImpl(std::vector<std::string> &data_registry, const std::tuple<Tp...> &in_params_tuple)
{
    // Because it is out of bound index so do nothing
    ARM_COMPUTE_UNUSED(data_registry);
    ARM_COMPUTE_UNUSED(in_params_tuple);
}

/** Function template to iterate over all input parameters tuple at compile time:
 *
 * @param[in,out] data_registry   Reference to a vector of input parameters data in a string format
 * @param[in]     in_params_tuple Constant reference to a tuple of different input data types
 */
template <std::size_t Index, typename... Tp>
inline typename std::enable_if < Index<sizeof...(Tp), void>::type
logParamsImpl(std::vector<std::string> &data_registry, const std::tuple<Tp...> &in_params_tuple)
{
    data_registry.push_back(arm_compute::to_string(std::get<Index>(in_params_tuple)));
    // Unfold the next tuple element
    logParamsImpl < Index + 1, Tp... > (data_registry, in_params_tuple);
}

/** Function Template with variable number of inputs to collect all the passed parameters from
 *  the logging macro ARM_COMPUTE_LOG_PARAMS(...)
 *
 * @param[in] ...ins The input parameters in the variadic template, taken by universal references Ts.. &&, (not by value)
 *                   to avoid detecting T as an abstract data type when passing any of these parameters as an L-value
 *                   reference to an abstract type.
 *
 * @return  Vector of the parameters' data in a string format
 */
template <typename... Ts>
const std::vector<std::string> logParams(Ts &&... ins)
{
    std::vector<std::string> data_registry{};
    std::tuple<Ts...>        in_params_tuple{ ins... };

    // Start logging the tuple elements, starting from 0 to tuple_size-1
    logParamsImpl<0>(data_registry, in_params_tuple);
    return data_registry;
}

/** Inline function to parse the input parameters string passed from strignizing of the variadic macro input
 *  #__VA_ARGS__.
 *  It is Inline to avoid the redefinition of this function each time this header is included
 *
 * @param[in] in_params_str Constant reference to a string consists of the names of the input parameters provided
 *                          as:ARM_COMPUTE_LOG_PARAMS(src0, src1) the params_names = "src0, src1"
 *
 * @return  Vector of strings containing all the names of the input parameters
 */
inline const std::vector<std::string> getParamsNames(const std::string &in_params_str)
{
    std::stringstream ss(in_params_str);

    // Vector containing all the names of the input parameters
    std::vector<std::string> names;
    std::string              temp;

    // Usually the input parameters string would be name of parameters separated
    // by ',' e.g. "src0, src1, policy"
    while(std::getline(ss, temp, ','))
    {
        names.push_back(temp);
    }
    for(auto &name : names)
    {
        // Totally get rid of white space characters
        name.erase(std::remove(name.begin(), name.end(), ' '), name.end());
    }
    return names;
}

/** It constructs the log message to be displayed by the logger by writing each parameter name and its
 *  corresponding data info string.
 *
 * @param[in] params_names  Constant reference to a string consists of the the input parameters' names
 *                          provided e.g.: ARM_COMPUTE_LOG_PARAMS(src0, src1) then params_names = "src0, src1"
 * @param[in] data_registry Constant reference to a registry of all parameters' data in string format,
 *                          stringnized by arm_compute::to_string()
 *
 * @return  Log message string to be displayed
 */
inline const std::string constructDataLog(const std::vector<std::string> &params_names,
                                          const std::vector<std::string> &data_registry)
{
    std::string dataLog = "\n ";
    ARM_COMPUTE_ERROR_ON(params_names.size() != data_registry.size());
    for(uint8_t i = 0; i < params_names.size(); ++i)
    {
        dataLog += params_names[i] + ": " + data_registry.at(i) + "\n ";
    }

    return dataLog;
}

/** Macro for logging input Parameters from any function.
 *  It detects the input parameters names, and their corresponding values before stringizing them using
 *  the overloaded arm_compute::to_string() type printer. Finally, displayed using the printer configured
 *  in the logger.
 *
 * @param[in] ... Input parameters
 */
#define ARM_COMPUTE_LOG_PARAMS(...)                                                           \
    do                                                                                        \
    {                                                                                         \
        ARM_COMPUTE_LOG_INFO_WITH_FUNCNAME_ACL(constructDataLog(getParamsNames(#__VA_ARGS__), \
                                                                logParams(__VA_ARGS__)));     \
    } while(false)
#endif /* SRC_COMMON_LOG_H */