conf: introduce snd_config_load_string()

Signed-off-by: Jaroslav Kysela <perex@perex.cz>

include/conf.h

@@ -89,6 +89,7 @@ const char *snd_config_topdir(void);
 int snd_config_top(snd_config_t **config);
 
 int snd_config_load(snd_config_t *config, snd_input_t *in);
+int snd_config_load_string(snd_config_t **config, const char *s, size_t size);
 int snd_config_load_override(snd_config_t *config, snd_input_t *in);
 int snd_config_save(snd_config_t *config, snd_output_t *out);
 int snd_config_update(void);

src/conf.c

@@ -2050,6 +2050,49 @@ int snd_config_load(snd_config_t *config, snd_input_t *in)
 	return _snd_config_load_with_include(config, in, 0, NULL);
 }
 
+/**
+ * \brief Loads a configuration tree from a string.
+ * \param[out] The function puts the handle to the configuration
+ *	       node loaded from the file(s) at the address specified
+ *             by \a config.
+ * \param[in] s String with the ASCII configuration
+ * \param[in] size String size, if zero, a C string is expected (with termination)
+ * \return Zero if successful, otherwise a negative error code.
+ *
+ * The definitions loaded from the string are put to \a config, which
+ * is created as a new top node.
+ *
+ * \par Errors:
+ * Any errors encountered when parsing the input or returned by hooks or
+ * functions.
+ */
+int snd_config_load_string(snd_config_t **config, const char *s, size_t size)
+{
+	snd_input_t *input;
+	snd_config_t *dst;
+	int err;
+
+	assert(config && s);
+	if (size == 0)
+		size = strlen(s);
+	err = snd_input_buffer_open(&input, s, size);
+	if (err < 0)
+		return err;
+	err = snd_config_top(&dst);
+	if (err < 0) {
+		snd_input_close(input);
+		return err;
+	}
+	err = snd_config_load(dst, input);
+	snd_input_close(input);
+	if (err < 0) {
+		snd_config_delete(dst);
+		return err;
+	}
+	*config = dst;
+	return 0;
+}
+
 /**
  * \brief Loads a configuration tree and overrides existing configuration nodes.
  * \param config Handle to a top level configuration node.

src/ucm/ucm_subs.c

@@ -213,32 +213,6 @@ struct lookup_iterate {
 	void *info;
 };
 
-static snd_config_t *parse_lookup_query(const char *query)
-{
-	snd_input_t *input;
-	snd_config_t *config;
-	int err;
-
-	err = snd_input_buffer_open(&input, query, strlen(query));
-	if (err < 0) {
-		uc_error("unable to create memory input buffer");
-		return NULL;
-	}
-	err = snd_config_top(&config);
-	if (err < 0) {
-		snd_input_close(input);
-		return NULL;
-	}
-	err = snd_config_load(config, input);
-	snd_input_close(input);
-	if (err < 0) {
-		snd_config_delete(config);
-		uc_error("wrong arguments '%s'", query);
-		return NULL;
-	}
-	return config;
-}
-
 static char *rval_lookup_main(snd_use_case_mgr_t *uc_mgr,
 			      const char *query,
 			      struct lookup_iterate *iter)
@@ -257,9 +231,11 @@ static char *rval_lookup_main(snd_use_case_mgr_t *uc_mgr,
 		return NULL;
 	}
 
-	config = parse_lookup_query(query);
-	if (config == NULL)
+	err = snd_config_load_string(&config, query, 0);
+	if (err < 0) {
+		uc_error("The lookup arguments '%s' are invalid", query);
 		return NULL;
+	}
 	if (iter->init && iter->init(uc_mgr, iter, config))
 		goto null;
 	if (snd_config_search(config, "field", &d)) {

test/lsb/config.c

@@ -598,6 +598,22 @@ static void test_evaluate_string(void)
 	}
 }
 
+static void test_load_string(void)
+{
+	const char **cfg, *configs[] = {
+		"a=1,b=2",
+		"j 3;z 15;",
+		"x 0 y -1",
+		NULL
+	};
+	snd_config_t *dst;
+
+	for (cfg = configs; *cfg; cfg++) {
+		ALSA_CHECK(snd_config_load_string(&dst, *cfg, 0));
+		ALSA_CHECK(snd_config_delete(dst));
+	}
+}
+
 int main(void)
 {
 	test_top();
@@ -629,5 +645,6 @@ int main(void)
 	test_iterators();
 	test_for_each();
 	test_evaluate_string();
+	test_load_string();
 	return TEST_EXIT_CODE();
 }