lib: move index/ into main lib/

simplify things a bit

lib/mu-scanner.hh

@@ -0,0 +1,122 @@
+/*
+** Copyright (C) 2020-2023 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_SCANNER_HH__
+#define MU_SCANNER_HH__
+
+#include <functional>
+#include <memory>
+#include <utils/mu-result.hh>
+
+#include <dirent.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+namespace Mu {
+
+/**
+ * @brief Maildir scanner
+ *
+ * Scans maildir (trees) recursively, and calls the Handler callback for
+ * directories & files.
+ *
+ * It filters out (i.e., does *not* call the handler for):
+ *  - files starting with '.'
+ *  - files that do not live in a cur / new leaf maildir
+ *  - directories '.' and '..' and 'tmp'
+*/
+class Scanner {
+	public:
+	enum struct HandleType {
+		/*
+		 * Mode: All
+		 */
+		File,
+		EnterNewCur, /* cur/ or new/ */
+		EnterDir,    /* some other directory */
+		LeaveDir,
+		/*
+		 * Mode: Maildir
+		 */
+		Maildir,
+	};
+
+	/**
+	 * Callback handler function
+	 *
+	 * path: full file-system path
+	 * statbuf: stat result or nullptr (for Mode::MaildirsOnly)
+	 * htype: HandleType. For Mode::MaildirsOnly only Maildir
+	 */
+	using Handler = std::function<
+	    bool(const std::string& path, struct stat* statbuf, HandleType htype)>;
+
+	/**
+	 * Running mode for this Scanner
+	 */
+	enum struct Mode {
+		All,		/**< Vanilla */
+		MaildirsOnly	/**< Only return maildir to handler */
+	};
+
+	/**
+	 * Construct a scanner object for scanning a directory, recursively.
+	 *
+	 * If handler is a directory
+	 *
+	 * @param root_dir root dir to start scanning
+	 * @param handler handler function for some direntry
+	 * @param options options to influence behavior
+	 */
+	Scanner(const std::string& root_dir, Handler handler, Mode mode = Mode::All);
+
+	/**
+	 * DTOR
+	 */
+	~Scanner();
+
+	/**#
+	 * Start the scan; this is a blocking call than runs until
+	 * finished or (from another thread) stop() is called.
+	 *
+	 * @return Ok if starting worked; an Error otherwise
+	 */
+	Result<void> start();
+
+	/**
+	 * Request stopping the scan if it's running; otherwise do nothing
+	 */
+	void stop();
+
+	/**
+	 * Is a scan currently running?
+	 *
+	 * @return true or false
+	 */
+	bool is_running() const;
+
+private:
+	struct Private;
+	std::unique_ptr<Private> priv_;
+};
+
+} // namespace Mu
+
+#endif /* MU_SCANNER_HH__ */