psutils: Move utility functions to utils.*pp

The files named version.hpp and version.cpp implement the --get-version
option of the psutils tool.

However, the files also contain some utility functions that would be
helpful for implementing other command line options, such as --update or
the planned new option --get-model.

Move the utility functions into new files named utils.hpp and utils.cpp.
The functions will be defined within a namespace named 'utils'.

Tested:
* Verified automated testcases ran successfully
* Verified --get-version option worked correctly
  * When using a psu.json file
  * When using D-Bus information

Change-Id: If902ee4581fce000af37073ac2e7a7b0ade01f78
Signed-off-by: Shawn McCarney <shawnmm@us.ibm.com>
diff --git a/tools/power-utils/utils.cpp b/tools/power-utils/utils.cpp
new file mode 100644
index 0000000..0afc4a8
--- /dev/null
+++ b/tools/power-utils/utils.cpp
@@ -0,0 +1,168 @@
+/**
+ * Copyright © 2024 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 "utils.hpp"
+
+#include "utility.hpp"
+
+#include <phosphor-logging/log.hpp>
+#include <xyz/openbmc_project/Common/Device/error.hpp>
+
+#include <exception>
+#include <iostream>
+#include <regex>
+#include <stdexcept>
+
+using namespace phosphor::logging;
+using namespace phosphor::power::util;
+using namespace sdbusplus::xyz::openbmc_project::Common::Device::Error;
+
+namespace utils
+{
+
+constexpr auto IBMCFFPSInterface =
+    "xyz.openbmc_project.Configuration.IBMCFFPSConnector";
+constexpr auto i2cBusProp = "I2CBus";
+constexpr auto i2cAddressProp = "I2CAddress";
+
+PsuI2cInfo getPsuI2c(sdbusplus::bus_t& bus, const std::string& psuInventoryPath)
+{
+    auto depth = 0;
+    auto objects = getSubTree(bus, "/", IBMCFFPSInterface, depth);
+    if (objects.empty())
+    {
+        throw std::runtime_error("Supported Configuration Not Found");
+    }
+
+    std::optional<std::uint64_t> i2cbus;
+    std::optional<std::uint64_t> i2caddr;
+
+    // GET a map of objects back.
+    // Each object will have a path, a service, and an interface.
+    for (const auto& [path, services] : objects)
+    {
+        auto service = services.begin()->first;
+
+        if (path.empty() || service.empty())
+        {
+            continue;
+        }
+
+        // Match the PSU identifier in the path with the passed PSU inventory
+        // path. Compare the last character of both paths to find the PSU bus
+        // and address. example: PSU path:
+        // /xyz/openbmc_project/inventory/system/board/Nisqually_Backplane/Power_Supply_Slot_0
+        // PSU inventory path:
+        // /xyz/openbmc_project/inventory/system/chassis/motherboard/powersupply0
+        if (path.back() == psuInventoryPath.back())
+        {
+            // Retrieve i2cBus and i2cAddress from array of properties.
+            auto properties =
+                getAllProperties(bus, path, IBMCFFPSInterface, service);
+            for (const auto& property : properties)
+            {
+                try
+                {
+                    if (property.first == i2cBusProp)
+                    {
+                        i2cbus = std::get<uint64_t>(properties.at(i2cBusProp));
+                    }
+                    else if (property.first == i2cAddressProp)
+                    {
+                        i2caddr =
+                            std::get<uint64_t>(properties.at(i2cAddressProp));
+                    }
+                }
+                catch (const std::exception& e)
+                {
+                    log<level::WARNING>(
+                        std::format("Error reading property {}: {}",
+                                    property.first, e.what())
+                            .c_str());
+                }
+            }
+
+            if (i2cbus.has_value() && i2caddr.has_value())
+            {
+                break;
+            }
+        }
+    }
+
+    if (!i2cbus.has_value() || !i2caddr.has_value())
+    {
+        throw std::runtime_error("Failed to get I2C bus or address");
+    }
+
+    return std::make_tuple(*i2cbus, *i2caddr);
+}
+
+std::unique_ptr<phosphor::pmbus::PMBusBase>
+    getPmbusIntf(std::uint64_t i2cBus, std::uint64_t i2cAddr)
+{
+    std::stringstream ss;
+    ss << std::hex << std::setw(4) << std::setfill('0') << i2cAddr;
+    return phosphor::pmbus::createPMBus(i2cBus, ss.str());
+}
+
+std::string readVPDValue(phosphor::pmbus::PMBusBase& pmbusIntf,
+                         const std::string& vpdName,
+                         const phosphor::pmbus::Type& type,
+                         const std::size_t& vpdSize)
+{
+    std::string vpdValue;
+    const std::regex illegalVPDRegex =
+        std::regex("[^[:alnum:]]", std::regex::basic);
+
+    try
+    {
+        vpdValue = pmbusIntf.readString(vpdName, type);
+    }
+    catch (const ReadFailure& e)
+    {
+        // Ignore the read failure, let pmbus code indicate failure.
+    }
+
+    if (vpdValue.size() != vpdSize)
+    {
+        log<level::INFO>(
+            std::format(" {} resize needed. size: {}", vpdName, vpdValue.size())
+                .c_str());
+        vpdValue.resize(vpdSize, ' ');
+    }
+
+    // Replace any illegal values with space(s).
+    std::regex_replace(vpdValue.begin(), vpdValue.begin(), vpdValue.end(),
+                       illegalVPDRegex, " ");
+
+    return vpdValue;
+}
+
+bool checkFileExists(const std::string& filePath)
+{
+    try
+    {
+        return std::filesystem::exists(filePath);
+    }
+    catch (const std::exception& e)
+    {
+        log<level::ERR>(std::format("Unable to check for existence of {}: {}",
+                                    filePath, e.what())
+                            .c_str());
+    }
+    return false;
+}
+
+} // namespace utils