add experimental self-updating script

include/functions.php

@@ -5506,4 +5506,18 @@
 
 		return null;
 	}
+
+	function tmpdirname($path, $prefix) {
+		// Use PHP's tmpfile function to create a temporary
+		// directory name. Delete the file and keep the name.
+		$tempname = tempnam($path,$prefix);
+		if (!$tempname)
+			return false;
+
+		if (!unlink($tempname))
+			return false;
+
+       return $tempname;
+	}
+
 ?>

update.php

@@ -28,6 +28,7 @@
 		print "  -cleanup-tags       - perform tags table maintenance\n";
 		print "  -get-feeds          - receive popular feeds from linked instances\n";
 		print "  -import USER FILE   - import articles from XML\n";
+		print "  -update-self        - update tt-rss installation to latest version\n";
 		print "  -quiet              - don't show messages\n";
 		print "  -indexes            - recreate missing schema indexes\n";
 		print "  -help               - show this help\n";
@@ -205,11 +206,179 @@
 		_debug("all done.");
 	}
 
+	if (in_array("-update-self", $op)) {
+		_debug("Warning: self-updating is experimental. Use at your own risk.");
+		_debug("Please backup your tt-rss directory before continuing. Your database will not be modified.");
+		_debug("Type 'yes' to continue.");
+
+		if (read_stdin() != 'yes')
+			exit;
+
+		$work_dir = dirname(__FILE__);
+		$parent_dir = dirname($work_dir);
+
+		if (!is_writable($work_dir) && !is_writable("$parent_dir")) {
+			_debug("Both current and parent directories should be writable as current user.");
+			exit;
+		}
+
+		if (!is_writable(sys_get_temp_dir())) {
+			_debug("System temporary directory should be writable as current user.");
+			exit;
+		}
+
+		_debug("Checking for tar...");
+
+		$system_rc = 0;
+		system("tar --version >/dev/null", $system_rc);
+
+		if ($system_rc != 0) {
+			_debug("Could not run tar executable (RC=$system_rc).");
+			exit;
+		}
+
+		_debug("Checking for latest version...");
+
+		$version_info = json_decode(fetch_file_contents("http://tt-rss.org/version.php"),
+			true);
+
+		if (!is_array($version_info)) {
+			_debug("Unable to fetch version information.");
+			exit;
+		}
+
+		$target_version = $version_info["version"];
+		$target_dir = "$parent_dir/tt-rss-$target_version";
+
+		_debug("Target version: $target_version");
+
+		if (version_compare(VERSION, $target_version) != -1 && !in_array("-force", $op)) {
+			_debug("You are on latest version. Update not needed.");
+			exit;
+		}
+		if (file_exists($target_dir)) {
+			_debug("Target directory $target_dir already exists.");
+			exit;
+		}
+
+		_debug("Downloading checksums...");
+		$md5sum_data = fetch_file_contents("http://tt-rss.org/download/md5sum.txt");
+
+		if (!$md5sum_data) {
+			_debug("Could not download checksums.");
+			exit;
+		}
+
+		$md5sum_data = explode("\n", $md5sum_data);
+
+		$tarball_url = "http://tt-rss.org/download/tt-rss-$target_version.tar.gz";
+		$data = fetch_file_contents($tarball_url);
+
+		if (!$data) {
+			_debug("Could not download distribution tarball ($tarball_url).");
+			exit;
+		}
+
+		_debug("Verifying tarball checksum...");
+
+		$target_md5sum = false;
+
+		foreach ($md5sum_data as $line) {
+			$pair = explode("  ", $line);
+
+			if ($pair[1] == "tt-rss-$target_version.tar.gz") {
+				$target_md5sum = $pair[0];
+				break;
+			}
+		}
+
+		if (!$target_md5sum) {
+			_debug("Unable to locate checksum for target version.");
+			exit;
+		}
+
+		$test_md5sum = md5($data);
+
+		if ($test_md5sum != $target_md5sum) {
+			_debug("Downloaded checksum doesn't match (got $test_md5sum, expected $target_md5sum).");
+			exit;
+		}
+
+		$tmp_file = tempnam(sys_get_temp_dir(), 'tt-rss');
+		_debug("Saving download to $tmp_file");
+
+		if (!file_put_contents($tmp_file, $data)) {
+			_debug("Unable to save download.");
+			exit;
+		}
+
+		if (!chdir($parent_dir)) {
+			_debug("Unable to change into parent directory.");
+			exit;
+		}
+
+		$old_dir = tmpdirname($parent_dir, "tt-rss-old");
+
+		_debug("Renaming current directory to ".basename($old_dir));
+		if (!rename($work_dir, $old_dir)) {
+			_debug("Unable to rename current directory.");
+			exit;
+		}
+
+		_debug("Extracting tarball...");
+		system("tar zxf $tmp_file", $system_rc);
+
+		if ($system_rc != 0) {
+			_debug("Error while extracting tarball (RC=$system_rc).");
+			exit;
+		}
+
+		_debug("Renaming target directory...");
+		if (!rename($target_dir, $work_dir)) {
+			_debug("Unable to rename target directory.");
+			exit;
+		}
+
+		chdir($work_dir);
+
+		_debug("Copying config.php...");
+		if (!copy("$old_dir/config.php", "$work_dir/config.php")) {
+			_debug("Unable to copy config.php to $work_dir.");
+			exit;
+		}
+
+		_debug("Cleaning up...");
+		unlink($tmp_file);
+
+		_debug("Fixing permissions...");
+
+		$directories = array(
+			CACHE_DIR,
+			CACHE_DIR . "/htmlpurifier",
+			CACHE_DIR . "/export",
+			CACHE_DIR . "/images",
+			CACHE_DIR . "/magpie",
+			CACHE_DIR . "/simplepie",
+			ICONS_DIR,
+			LOCK_DIRECTORY);
+
+		foreach ($directories as $dir) {
+			_debug("-> $dir");
+			chmod($dir, 0777);
+		}
+
+		_debug("Upgrade completed.");
+		_debug("Your old tt-rss directory is saved at $old_dir. ".
+			"Please migrate locally modified files (if any) and remove it.");
+		_debug("You might need to re-enter current directory in shell to see new files.");
+	}
+
 	db_close($link);
 
 	if ($lock_handle != false) {
 		fclose($lock_handle);
 	}
 
-	unlink(LOCK_DIRECTORY . "/$lock_filename");
+	if (file_exists(LOCK_DIRECTORY . "/$lock_filename"))
+		unlink(LOCK_DIRECTORY . "/$lock_filename");
 ?>