LDAP: Add the persistency for the "Enabled" property

This property will control that whether the LDAP service would
be started or not.

We are persisting this property using cereal, other properties
is being persisted through nslcd.conf, nslcd doesn't give us
a way to put this property under nslcd.conf.

Tested By:
      Test the persistency of enabled property.
        Verified that it was getting persisted across restart/reboot.

Change-Id: Id64b23b71865bac15d3be2d79abad615aa576bea
Signed-off-by: Ratan Gupta <ratagupt@linux.vnet.ibm.com>

1 files changed, 88 insertions, 0 deletions

diff --git a/phosphor-ldap-config/ldap_serialize.cpp b/phosphor-ldap-config/ldap_serialize.cpp
new file mode 100644
index 0000000..510686c
--- /dev/null
+++ b/phosphor-ldap-config/ldap_serialize.cpp
@@ -0,0 +1,88 @@
+#include <cereal/types/string.hpp>
+#include <cereal/types/vector.hpp>
+#include <cereal/archives/binary.hpp>
+#include <fstream>
+
+#include "ldap_serialize.hpp"
+#include "ldap_configuration.hpp"
+#include <phosphor-logging/log.hpp>
+#include "config.h"
+
+// Register class version
+// From cereal documentation;
+// "This macro should be placed at global scope"
+CEREAL_CLASS_VERSION(phosphor::ldap::Config, CLASS_VERSION);
+
+namespace phosphor
+{
+namespace ldap
+{
+
+using namespace phosphor::logging;
+
+/** @brief Function required by Cereal to perform serialization.
+ *  @tparam Archive - Cereal archive type (binary in our case).
+ *  @param[in] archive - reference to Cereal archive.
+ *  @param[in] config - const reference to ldap config.
+ *  @param[in] version - Class version that enables handling
+ *                       a serialized data across code levels
+ */
+template <class Archive>
+void save(Archive& archive, const Config& config, const std::uint32_t version)
+{
+    archive(config.enabled());
+}
+
+/** @brief Function required by Cereal to perform deserialization.
+ *  @tparam Archive - Cereal archive type (binary in our case).
+ *  @param[in] archive - reference to Cereal archive.
+ *  @param[in] config -  reference of ldap config object.
+ *  @param[in] version - Class version that enables handling
+ *                       a serialized data across code levels
+ */
+template <class Archive>
+void load(Archive& archive, Config& config, const std::uint32_t version)
+{
+    bool enabled = false;
+    archive(enabled);
+    config.enabled(enabled);
+}
+
+fs::path serialize(const Config& config, const fs::path& path)
+{
+    fs::create_directories(path.parent_path());
+
+    std::ofstream os(path.string(), std::ios::binary);
+    cereal::BinaryOutputArchive oarchive(os);
+    oarchive(config);
+    return path;
+}
+
+bool deserialize(const fs::path& path, Config& config)
+{
+    try
+    {
+        if (fs::exists(path))
+        {
+            std::ifstream is(path.c_str(), std::ios::in | std::ios::binary);
+            cereal::BinaryInputArchive iarchive(is);
+            iarchive(config);
+            return true;
+        }
+        return false;
+    }
+    catch (cereal::Exception& e)
+    {
+        log<level::ERR>(e.what());
+        std::error_code ec;
+        fs::remove(path, ec);
+        return false;
+    }
+    catch (const fs::filesystem_error& e)
+    {
+        return false;
+    }
+}
+
+} // namespace ldap
+} // namespace phosphor