[tracker-miners/wip/carlosg/perf-squeeze: 12/16] tracker-miner-fs: Add --dry-run commandline argument

[Carlos Garnacho <carlosg src gnome org>]

commit a913c4d3981af36128ee24d99a7697cb83e07d88
Author: Carlos Garnacho <carlosg gnome org>
Date:   Sat Jul 4 21:02:20 2020 +0200

    tracker-miner-fs: Add --dry-run commandline argument
    
    This makes tracker-miner-fs run avoiding the filesystem for the most
    part, a in-memory database is used, and other ancillary files are not
    written to.

 src/miners/fs/tracker-main.c | 23 +++++++++++++++--------
 1 file changed, 15 insertions(+), 8 deletions(-)
---
diff --git a/src/miners/fs/tracker-main.c b/src/miners/fs/tracker-main.c
index 150cf9b56..278476411 100644
--- a/src/miners/fs/tracker-main.c
+++ b/src/miners/fs/tracker-main.c
@@ -64,6 +64,7 @@ static gboolean version;
 static guint miners_timeout_id = 0;
 static gboolean do_crawling = FALSE;
 static gchar *domain_ontology_name = NULL;
+static gboolean dry_run = FALSE;
 
 static GOptionEntry entries[] = {
        { "initial-sleep", 's', 0,
@@ -83,6 +84,10 @@ static GOptionEntry entries[] = {
          G_OPTION_ARG_STRING, &domain_ontology_name,
          N_("Runs for a specific domain ontology"),
          NULL },
+       { "dry-run", 'r', 0,
+         G_OPTION_ARG_NONE, &dry_run,
+         N_("Avoids changes in the filesystem"),
+         NULL },
        { "version", 'V', 0,
          G_OPTION_ARG_NONE, &version,
          N_("Displays version information"),
@@ -426,7 +431,7 @@ miner_finished_cb (TrackerMinerFS *fs,
                total_directories_found,
                total_files_found);
 
-       if (do_crawling) {
+       if (do_crawling && !dry_run) {
                tracker_miner_files_set_last_crawl_done (TRACKER_MINER_FILES (fs),
                                                         TRUE);
        }
@@ -754,16 +759,17 @@ setup_connection_and_endpoint (TrackerDomainOntology    *domain,
                                TrackerEndpointDBus     **endpoint,
                                GError                  **error)
 {
-       GFile *store, *ontology;
+       GFile *store = NULL, *ontology;
 
-       store = get_cache_dir (domain);
+       if (!dry_run)
+               store = get_cache_dir (domain);
        ontology = tracker_domain_ontology_get_ontology (domain);
        *sparql_conn = tracker_sparql_connection_new (get_fts_connection_flags (),
                                                      store,
                                                      ontology,
                                                      NULL,
                                                      error);
-       g_object_unref (store);
+       g_clear_object (&store);
 
        if (!*sparql_conn)
                return FALSE;
@@ -966,10 +972,11 @@ main (gint argc, gchar *argv[])
         * event of a crash, this is changed back on shutdown if
         * everything appears to be fine.
         */
-       tracker_miner_files_set_need_mtime_check (TRACKER_MINER_FILES (miner_files), TRUE);
+       if (!dry_run) {
+               tracker_miner_files_set_need_mtime_check (TRACKER_MINER_FILES (miner_files), TRUE);
+               tracker_miner_files_set_mtime_checking (TRACKER_MINER_FILES (miner_files), do_mtime_checking);
+       }
 
-       /* Configure files miner */
-       tracker_miner_files_set_mtime_checking (TRACKER_MINER_FILES (miner_files), do_mtime_checking);
        g_signal_connect (miner_files, "finished",
                          G_CALLBACK (miner_finished_cb),
                          NULL);
@@ -984,7 +991,7 @@ main (gint argc, gchar *argv[])
 
        g_debug ("Shutdown started");
 
-       if (miners_timeout_id == 0 && !miner_needs_check (miner_files)) {
+       if (!dry_run && miners_timeout_id == 0 && !miner_needs_check (miner_files)) {
                tracker_miner_files_set_need_mtime_check (TRACKER_MINER_FILES (miner_files), FALSE);
                save_current_locale (domain_ontology);
        }