lib: move index/ into main lib/

simplify things a bit

lib/mu-indexer.hh

@@ -0,0 +1,126 @@
+/*
+** Copyright (C) 2022 Dirk-Jan C. Binnema <djcb@djcbsoftware.nl>
+**
+** This program is free software; you can redistribute it and/or modify it
+** under the terms of the GNU General Public License as published by the
+** Free Software Foundation; either version 3, or (at your option) any
+** later version.
+**
+** This program is distributed in the hope that it will be useful,
+** but WITHOUT ANY WARRANTY; without even the implied warranty of
+** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+** GNU General Public License for more details.
+**
+** You should have received a copy of the GNU General Public License
+** along with this program; if not, write to the Free Software Foundation,
+** Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+**
+*/
+
+#ifndef MU_INDEXER_HH__
+#define MU_INDEXER_HH__
+
+#include <atomic>
+#include <memory>
+#include <chrono>
+
+namespace Mu {
+
+class Store;
+
+/// An object abstracting the index process.
+class Indexer {
+public:
+	/**
+	 * Construct an indexer object
+	 *
+	 * @param store the message store to use
+	 */
+	Indexer(Store& store);
+
+	/**
+	 * DTOR
+	 */
+	~Indexer();
+
+	/// A configuration object for the indexer
+	struct Config {
+		bool scan{true};
+		/**< scan for new messages */
+		bool cleanup{true};
+		/**< clean messages no longer in the file system */
+		size_t max_threads{};
+		/**< maximum # of threads to use */
+		bool ignore_noupdate{};
+		/**< ignore .noupdate files */
+		bool lazy_check{};
+		/**< whether to skip directories that don't have a changed
+		 * mtime */
+	};
+
+	/**
+	 * Start indexing. If already underway, do nothing. This returns
+	 * immediately after starting, with the work being done in the
+	 * background.
+	 *
+	 * @param conf a configuration object
+	 *
+	 * @return true if starting worked or an indexing process was already
+	 * underway; false otherwise.
+	 *
+	 */
+	bool start(const Config& conf);
+
+	/**
+	 * Stop indexing. If not indexing, do nothing.
+	 *
+	 *
+	 * @return true if we stopped indexing, or indexing was not underway.
+	 * False otherwise.
+	 */
+	bool stop();
+
+	/**
+	 * Is an indexing process running?
+	 *
+	 * @return true or false.
+	 */
+	bool is_running() const;
+
+	// Object describing current progress
+	struct Progress {
+		void reset()
+		{
+			running = false;
+			checked = updated = removed = 0;
+		}
+
+		std::atomic<bool>   running{}; /**< Is an index operation in progress? */
+		std::atomic<size_t> checked{}; /**< Number of messages checked for changes */
+		std::atomic<size_t> updated{}; /**< Number of messages (re)parsed/added/updated */
+		std::atomic<size_t> removed{}; /**< Number of message removed from store */
+	};
+
+	/**
+	 * Get an object describing the current progress. The progress object
+	 * describes the most recent indexing job, and is reset upon a fresh
+	 * start().
+	 *
+	 * @return a progress object.
+	 */
+	const Progress& progress() const;
+
+	/**
+	 * Last time indexing was completed.
+	 *
+	 * @return the time or 0
+	 */
+	::time_t completed() const;
+
+private:
+	struct Private;
+	std::unique_ptr<Private> priv_;
+};
+
+} // namespace Mu
+#endif /* MU_INDEXER_HH__ */