blkdebug: Use bdrv_open options instead of filename (f4681212) · Commits · SUMMER2020 / students / proj-2021291

block/blkdebug.c

+82 −32

Original line number	Diff line number	Diff line
		@@ -273,11 +273,6 @@ static int read_config(BDRVBlkdebugState s, const char filename)
		int ret;
		struct add_rule_data d;

		/* Allow usage without config file */
		if (!*filename) {
		return 0;
		}

		f = fopen(filename, "r");
		if (f == NULL) {
		return -errno;
		@@ -304,44 +299,99 @@ fail:
		}

		/* Valid blkdebug filenames look like blkdebug:path/to/config:path/to/image */
		static int blkdebug_open(BlockDriverState bs, const char filename,
		QDict *options, int flags)
		static void blkdebug_parse_filename(const char filename, QDict options,
		Error **errp)
		{
		BDRVBlkdebugState *s = bs->opaque;
		int ret;
		char config, c;
		const char *c;

		/* Parse the blkdebug: prefix */
		if (strncmp(filename, "blkdebug:", strlen("blkdebug:"))) {
		return -EINVAL;
		if (!strstart(filename, "blkdebug:", &filename)) {
		error_setg(errp, "File name string must start with 'blkdebug:'");
		return;
		}
		filename += strlen("blkdebug:");

		/* Read rules from config file */
		/* Parse config file path */
		c = strchr(filename, ':');
		if (c == NULL) {
		return -EINVAL;
		error_setg(errp, "blkdebug requires both config file and image path");
		return;
		}

		if (c != filename) {
		QString *config_path;
		config_path = qstring_from_substr(filename, 0, c - filename - 1);
		qdict_put(options, "config", config_path);
		}

		/* TODO Allow multi-level nesting and set file.filename here */
		filename = c + 1;
		qdict_put(options, "x-image", qstring_from_str(filename));
		}

		static QemuOptsList runtime_opts = {
		.name = "blkdebug",
		.head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
		.desc = {
		{
		.name = "config",
		.type = QEMU_OPT_STRING,
		.help = "Path to the configuration file",
		},
		{
		.name = "x-image",
		.type = QEMU_OPT_STRING,
		.help = "[internal use only, will be removed]",
		},
		{ /* end of list */ }
		},
		};

		static int blkdebug_open(BlockDriverState bs, const char dummy,
		QDict *options, int flags)
		{
		BDRVBlkdebugState *s = bs->opaque;
		QemuOpts *opts;
		Error *local_err = NULL;
		const char filename, config;
		int ret;

		opts = qemu_opts_create_nofail(&runtime_opts);
		qemu_opts_absorb_qdict(opts, options, &local_err);
		if (error_is_set(&local_err)) {
		qerror_report_err(local_err);
		error_free(local_err);
		ret = -EINVAL;
		goto fail;
		}

		config = g_strdup(filename);
		config[c - filename] = '\0';
		/* Read rules from config file */
		config = qemu_opt_get(opts, "config");
		if (config) {
		ret = read_config(s, config);
		g_free(config);
		if (ret < 0) {
		return ret;
		goto fail;
		}
		}
		filename = c + 1;

		/* Set initial state */
		s->state = 1;

		/* Open the backing file */
		filename = qemu_opt_get(opts, "x-image");
		if (filename == NULL) {
		ret = -EINVAL;
		goto fail;
		}

		ret = bdrv_file_open(&bs->file, filename, NULL, flags);
		if (ret < 0) {
		return ret;
		goto fail;
		}

		return 0;
		ret = 0;
		fail:
		qemu_opts_del(opts);
		return ret;
		}

		static void error_callback_bh(void *opaque)
		@@ -571,9 +621,9 @@ static int64_t blkdebug_getlength(BlockDriverState *bs)
		static BlockDriver bdrv_blkdebug = {
		.format_name = "blkdebug",
		.protocol_name = "blkdebug",

		.instance_size = sizeof(BDRVBlkdebugState),

		.bdrv_parse_filename = blkdebug_parse_filename,
		.bdrv_file_open = blkdebug_open,
		.bdrv_close = blkdebug_close,
		.bdrv_getlength = blkdebug_getlength,