env.cpp

/**
 * Copyright © 2016 IBM Corporation
 *
 * 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.
 */

#include <cstdlib>
#include <fstream>
#include <string>
#include "hwmon.hpp"
#include "sensorset.hpp"

std::string getEnv(
    const char* prefix, const SensorSet::key_type& sensor)
{
    std::string key;
    std::string value;

    key.assign(prefix);
    key.append(1, '_');
    key.append(sensor.first);
    key.append(sensor.second);
    auto env = getenv(key.c_str());
    if (env)
    {
        value.assign(env);
    }

    return value;
}

std::string getEnv(
    const char* prefix,
    const std::string& type,
    const std::string& id)
{
    SensorSet::key_type sensor{type, id};
    return getEnv(prefix, sensor);
}

std::string getIndirectLabelEnv(
    const char* prefix, std::string path, const SensorSet::key_type& sensor)
{
    std::string key;
    std::string value;

    path.append(sensor.first);
    path.append(sensor.second);
    path.append(1, '_');
    path.append(hwmon::entry::label);

    std::ifstream handle(path.c_str());
    if (handle.fail())
    {
        return value;
    }

    std::string content(
        (std::istreambuf_iterator<char>(handle)),
        (std::istreambuf_iterator<char>()));

    if (content.empty())
    {
        return value;
    }

    content.pop_back();

    key.assign(prefix);
    key.append(1, '_');
    key.append(sensor.first);
    key.append(content);
    auto env = getenv(key.c_str());
    if (env)
    {
        value.assign(env);
    }

    return value;
}

// vim: tabstop=8 expandtab shiftwidth=4 softtabstop=4