[context] Make support for libdnf5 conf drop-in, overrides conditional

In previous commits, support for libdnf5 drop-in configuration
directories and directories with repositories configuration overrides
was added to the context part of libdnf.

This changes the behavior of libdnf. Therefore, the new behavior can now
be turned off during library compilation.

Added build options:
ENABLE_DNF5_CONF_DROP_IN         - support for drop-in directories
ENABLE_DNF5_CONF_REPOS_OVERRIDE  - support for repositories overrides

Author: jrohel

CMakeLists.txt

@@ -31,6 +31,8 @@ option(WITH_GTKDOC "Enables libdnf GTK-Doc HTML documentation" ON)
 option(WITH_HTML "Enables hawkey HTML generation" ON)
 option(WITH_MAN "Enables hawkey man page generation" ON)
 option(WITH_ZCHUNK "Build with zchunk support" ON)
+option(ENABLE_DNF5_CONF_DROP_IN "Build with support for libdnf5 drop-in configuration directories?" ON)
+option(ENABLE_DNF5_CONF_REPOS_OVERRIDE "Build with support for libdnf5 repository configuration overrides?" ON)
 option(ENABLE_RHSM_SUPPORT "Build with Red Hat Subscription Manager support?" OFF)
 option(ENABLE_SOLV_URPMREORDER "Build with support for URPM-like solution reordering?" OFF)
 option(WITH_TESTS "Enables unit tests" ON)
@@ -132,6 +134,16 @@ add_definitions(-DG_LOG_DOMAIN="libdnf")
 # tests
 add_definitions(-DTESTDATADIR="${CMAKE_SOURCE_DIR}/data/tests")
 
+# Use libdnf5 drop-in configuration directories including distribution configuration.
+if(ENABLE_DNF5_CONF_DROP_IN)
+    add_definitions(-DDNF5_CONF_DROP_IN)
+endif()
+
+# Use libdnf5 repository overrides. Save repo conf chnges to "99-config_manager.repo" override.
+if(ENABLE_DNF5_CONF_REPOS_OVERRIDE)
+    add_definitions(-DDNF5_CONF_REPOS_OVERRIDE)
+endif()
+
 # librhsm
 if(ENABLE_RHSM_SUPPORT)
     add_definitions(-DRHSM_SUPPORT)

libdnf/dnf-context.cpp

@@ -4037,6 +4037,7 @@ libdnf::ConfigMain & getGlobalMainConfig(bool canReadConfigFile)
 
         const std::string cfgPath{globalMainConfig->config_file_path().getValue()};
         try {
+#ifdef DNF5_CONF_DROP_IN
             std::string conf_dir_path{CONF_DIR};
             std::string dist_conf_dir_path{DISTRIBUTION_CONF_DIR};
 
@@ -4057,6 +4058,7 @@ libdnf::ConfigMain & getGlobalMainConfig(bool canReadConfigFile)
                 parser.read(path);
                 load_from_parser(parser, path);
             }
+#endif
 
             // Finally, if a user configuration filename is defined or the file exists in the default location,
             // it will be loaded.

libdnf/dnf-repo.cpp

@@ -62,7 +62,9 @@
 #include "utils/url-encode.hpp"
 #include "utils/utils.hpp"
 
+#ifdef DNF5_CONF_REPOS_OVERRIDE
 #include <map>
+#endif
 #include <set>
 #include <string>
 #include <vector>
@@ -88,7 +90,9 @@ typedef struct
     LrHandle        *repo_handle;
     LrResult        *repo_result;
     LrUrlVars       *urlvars;
+#ifdef DNF5_CONF_REPOS_OVERRIDE
     std::map<std::string, std::string> *config_changes; // dnf_repo_set_data, dnf_repo_commit
+#endif
     bool            unit_test_mode;  /* ugly hack for unit tests */
 } DnfRepoPrivate;
 
@@ -124,8 +128,10 @@ dnf_repo_finalize(GObject *object)
     if (priv->context != NULL)
         g_object_remove_weak_pointer(G_OBJECT(priv->context),
                                      (void **) &priv->context);
+#ifdef DNF5_CONF_REPOS_OVERRIDE
     if (priv->config_changes)
         delete priv->config_changes;
+#endif
 
     G_OBJECT_CLASS(dnf_repo_parent_class)->finalize(object);
 }
@@ -930,6 +936,7 @@ dnf_repo_conf_from_gkeyfile(DnfRepo *repo, const char *repoId, GKeyFile *gkeyFil
     }
 }
 
+#ifdef DNF5_CONF_REPOS_OVERRIDE
 /* Loads repository configuration overrides */
 static void
 dnf_repo_conf_load_overrides(DnfRepo *repo, const char *repoId)
@@ -987,7 +994,7 @@ dnf_repo_conf_load_overrides(DnfRepo *repo, const char *repoId)
         }
     }
 }
-
+#endif
 
 static void
 dnf_repo_apply_setopts(libdnf::ConfigRepo &config, const char *repoId)
@@ -1032,7 +1039,9 @@ dnf_repo_set_keyfile_data(DnfRepo *repo, gboolean reloadFromGKeyFile, GError **e
     // Reload repository configuration from keyfile.
     if (reloadFromGKeyFile) {
         dnf_repo_conf_from_gkeyfile(repo, repoId, priv->keyfile);
+#ifdef DNF5_CONF_REPOS_OVERRIDE
         dnf_repo_conf_load_overrides(repo, repoId);
+#endif
         dnf_repo_apply_setopts(*conf, repoId);
     }
 
@@ -1314,7 +1323,9 @@ dnf_repo_setup(DnfRepo *repo, GError **error) try
 
     auto conf = priv->repo->getConfig();
     dnf_repo_conf_from_gkeyfile(repo, repoId, priv->keyfile);
+#ifdef DNF5_CONF_REPOS_OVERRIDE
     dnf_repo_conf_load_overrides(repo, repoId);
+#endif
     dnf_repo_apply_setopts(*conf, repoId);
 
     auto sslverify = conf->sslverify().getValue();
@@ -2109,18 +2120,20 @@ dnf_repo_set_data(DnfRepo *repo,
 {
     DnfRepoPrivate *priv = GET_PRIVATE(repo);
 
+#ifdef DNF5_CONF_REPOS_OVERRIDE
     // we note the changes
     // dnf_repo_commit writes them to the override configuration file
     if (!priv->config_changes) {
         priv->config_changes = new std::map<std::string, std::string>;
     }
     (*priv->config_changes)[parameter] = value;
+#endif
 
     g_key_file_set_string(priv->keyfile, priv->repo->getId().c_str(), parameter, value);
     return TRUE;
 } CATCH_TO_GERROR(FALSE)
 
-
+#ifdef DNF5_CONF_REPOS_OVERRIDE
 static std::string
 get_repos_config_override_dir_path(DnfRepo *repo)
 {
@@ -2148,6 +2161,7 @@ modify_config(libdnf::ConfigParser & parser, const std::string & section_id, con
         parser.setValue(section_id, key_val.first, key_val.second, "");
     }
 }
+#endif
 
 /**
  * dnf_repo_commit:
@@ -2175,6 +2189,7 @@ dnf_repo_commit(DnfRepo *repo, GError **error) try
         return FALSE;
     }
 
+#ifdef DNF5_CONF_REPOS_OVERRIDE
     constexpr const char * REPOS_OVERRIDE_CFG_HEADER =
     "# Generated by libdnf.\n# Do not modify this file manually.\n";
     const std::string CFG_MANAGER_REPOS_OVERRIDE_FILENAME = "99-config_manager.repo";
@@ -2209,8 +2224,16 @@ dnf_repo_commit(DnfRepo *repo, GError **error) try
         delete priv->config_changes;
         priv->config_changes = nullptr;
     }
-
     return TRUE;
+
+#else
+
+    /* dump updated file to disk */
+    data = g_key_file_to_data(priv->keyfile, NULL, error);
+    if (data == NULL)
+        return FALSE;
+    return g_file_set_contents(priv->filename, data, -1, error);
+#endif
 } CATCH_TO_GERROR(FALSE)
 
 /**