accept multiple --config requests for multiple channel groups

The previous UI implementation supported the selection of a channel
group, and defaulted to the device's global options. This let users
either manipulate global or a single channel group's parmeters.

Extend the user interface. Accept multiple -c specs. Apply the remaining
key-value pairs to the channel group which optionally can get specified
in the first item of a -c spec. This lets users modify several channel
groups' parameters in a single program invocation, including arbitrary
combinations including the device's global parameters.

This extension is completely backwards compatible. When a -c spec lacks
a 'channel_group=' item, then the -g spec is used, which defaults to the
global parameters.

Either an empty string or the 'global' literal can be used to select the
global parameters. Several -c specs can select the same channel group.
This can be useful when command lines get generated by other programs.

device.c

@@ -66,22 +66,31 @@ GSList *device_scan(void)
 /**
  * Lookup a channel group from its name.
  *
- * Uses the previously stored option value to lookup a channel group.
- * Returns a reference to the channel group when the lookup succeeded,
- * or #NULL after lookup failure, or #NULL for the global channel group
- * (the device's global parameters). Emits an error message when the
- * lookup failed while a channel group's name was specified.
+ * Uses the caller specified channel group name, or a previously stored
+ * option value as a fallback. Returns a reference to the channel group
+ * when the lookup succeeded, or #NULL after lookup failure, as well as
+ * #NULL for the global channel group (the device).
+ *
+ * Accepts either #NULL pointer, or an empty string, or the "global"
+ * literal to address the global channel group (the device). Emits an
+ * error message when the lookup failed while a name was specified.
  *
  * @param[in] sdi Device instance.
+ * @param[in] cg_name Caller provided channel group name.
  *
  * @returns The channel group, or #NULL for failed lookup.
  */
-struct sr_channel_group *lookup_channel_group(struct sr_dev_inst *sdi)
+struct sr_channel_group *lookup_channel_group(struct sr_dev_inst *sdi,
+	const char *cg_name)
 {
 	struct sr_channel_group *cg;
 	GSList *l, *channel_groups;
 
-	if (!opt_channel_group)
+	if (!cg_name)
+		cg_name = opt_channel_group;
+	if (cg_name && g_ascii_strcasecmp(cg_name, "global") == 0)
+		cg_name = NULL;
+	if (!cg_name || !*cg_name)
 		return NULL;
 
 	channel_groups = sr_dev_inst_channel_groups_get(sdi);
@@ -92,11 +101,11 @@ struct sr_channel_group *lookup_channel_group(struct sr_dev_inst *sdi)
 
 	for (l = channel_groups; l; l = l->next) {
 		cg = l->data;
-		if (g_ascii_strcasecmp(opt_channel_group, cg->name) != 0)
+		if (g_ascii_strcasecmp(cg_name, cg->name) != 0)
 			continue;
 		return cg;
 	}
-	g_critical("Invalid channel group '%s'", opt_channel_group);
+	g_critical("Invalid channel group '%s'", cg_name);
 
 	return NULL;
 }

main.c

@@ -113,7 +113,6 @@ static void get_option(void)
 	const struct sr_key_info *ci;
 	GSList *devices;
 	GVariant *gvar;
-	GHashTable *devargs;
 	int ret;
 	char *s;
 	struct sr_dev_driver *driver;
@@ -136,14 +135,11 @@ static void get_option(void)
 		return;
 	}
 
-	cg = lookup_channel_group(sdi);
+	cg = lookup_channel_group(sdi, NULL);
 	if (!(ci = sr_key_info_name_get(SR_KEY_CONFIG, opt_get)))
 		g_critical("Unknown option '%s'", opt_get);
 
-	if ((devargs = parse_generic_arg(opt_config, FALSE, NULL)))
-		set_dev_options(sdi, devargs);
-	else
-		devargs = NULL;
+	set_dev_options_array(sdi, opt_configs);
 
 	if ((ret = maybe_config_get(driver, sdi, cg, ci->key, &gvar)) != SR_OK)
 		g_critical("Failed to get '%s': %s", opt_get, sr_strerror(ret));
@@ -171,24 +167,18 @@ static void get_option(void)
 
 	g_variant_unref(gvar);
 	sr_dev_close(sdi);
-	if (devargs)
-		g_hash_table_destroy(devargs);
 }
 
 static void set_options(void)
 {
 	struct sr_dev_inst *sdi;
 	GSList *devices;
-	GHashTable *devargs;
 
-	if (!opt_config) {
+	if (!opt_configs) {
 		g_critical("No setting specified.");
 		return;
 	}
 
-	if (!(devargs = parse_generic_arg(opt_config, FALSE, NULL)))
-		return;
-
 	if (!(devices = device_scan())) {
 		g_critical("No devices found.");
 		return;
@@ -201,11 +191,9 @@ static void set_options(void)
 		return;
 	}
 
-	set_dev_options(sdi, devargs);
+	set_dev_options_array(sdi, opt_configs);
 
 	sr_dev_close(sdi);
-	g_hash_table_destroy(devargs);
-
 }
 
 int main(int argc, char **argv)

options.c

@@ -31,7 +31,7 @@ gboolean opt_wait_trigger = FALSE;
 gchar *opt_input_file = NULL;
 gchar *opt_output_file = NULL;
 gchar *opt_drv = NULL;
-gchar *opt_config = NULL;
+gchar **opt_configs = NULL;
 gchar *opt_channels = NULL;
 gchar *opt_channel_group = NULL;
 gchar *opt_triggers = NULL;
@@ -79,7 +79,6 @@ static gboolean check_ ## option                                          \
 }
 
 CHECK_ONCE(opt_drv)
-CHECK_ONCE(opt_config)
 CHECK_ONCE(opt_input_format)
 CHECK_ONCE(opt_output_format)
 CHECK_ONCE(opt_transform_module)
@@ -112,7 +111,7 @@ static const GOptionEntry optargs[] = {
 			"Set loglevel (5 is most verbose)", NULL},
 	{"driver", 'd', 0, G_OPTION_ARG_CALLBACK, &check_opt_drv,
 			"The driver to use", NULL},
-	{"config", 'c', 0, G_OPTION_ARG_CALLBACK, &check_opt_config,
+	{"config", 'c', 0, G_OPTION_ARG_STRING_ARRAY, &opt_configs,
 			"Specify device configuration options", NULL},
 	{"input-file", 'i', 0, G_OPTION_ARG_FILENAME_ARRAY, &input_file_array,
 			"Load input from file", NULL},

session.c

@@ -654,19 +654,51 @@ int opt_to_gvar(char *key, char *value, struct sr_config *src)
 	return ret;
 }
 
+int set_dev_options_array(struct sr_dev_inst *sdi, char **opts)
+{
+	size_t opt_idx;
+	const char *opt_text;
+	GHashTable *args;
+	int ret;
+
+	for (opt_idx = 0; opts && opts[opt_idx]; opt_idx++) {
+		opt_text = opts[opt_idx];
+		args = parse_generic_arg(opt_text, FALSE, "channel_group");
+		if (!args)
+			continue;
+		ret = set_dev_options(sdi, args);
+		g_hash_table_destroy(args);
+		if (ret != SR_OK)
+			return ret;
+	}
+
+	return SR_OK;
+}
+
 int set_dev_options(struct sr_dev_inst *sdi, GHashTable *args)
 {
 	struct sr_config src;
+	const char *cg_name;
 	struct sr_channel_group *cg;
 	GHashTableIter iter;
 	gpointer key, value;
 	int ret;
 
+	/*
+	 * Not finding the 'sigrok_key' key (optional user specified
+	 * channel group name) in the current options group's hash table
+	 * is perfectly fine. In that case the -g selection is used,
+	 * which defaults to "the device" (global parameters).
+	 */
+	cg_name = g_hash_table_lookup(args, "sigrok_key");
+	cg = lookup_channel_group(sdi, cg_name);
+
 	g_hash_table_iter_init(&iter, args);
 	while (g_hash_table_iter_next(&iter, &key, &value)) {
+		if (g_ascii_strcasecmp(key, "sigrok_key") == 0)
+			continue;
 		if ((ret = opt_to_gvar(key, value, &src)) != 0)
 			return ret;
-		cg = lookup_channel_group(sdi);
 		if ((ret = maybe_config_set(sr_dev_inst_driver_get(sdi), sdi, cg,
 				src.key, src.data)) != SR_OK) {
 			g_critical("Failed to set device option '%s': %s.",
@@ -682,7 +714,6 @@ void run_session(void)
 {
 	struct df_arg_desc df_arg;
 	GSList *devices, *real_devices, *sd;
-	GHashTable *devargs;
 	GVariant *gvar;
 	struct sr_session *session;
 	struct sr_trigger *trigger;
@@ -765,12 +796,9 @@ void run_session(void)
 		return;
 	}
 
-	if (opt_config) {
-		if ((devargs = parse_generic_arg(opt_config, FALSE, NULL))) {
-			if (set_dev_options(sdi, devargs) != SR_OK)
-				return;
-			g_hash_table_destroy(devargs);
-		}
+	if (opt_configs) {
+		if (set_dev_options_array(sdi, opt_configs) != SR_OK)
+			return;
 	}
 
 	if (select_channels(sdi) != SR_OK) {

show.c

@@ -441,7 +441,7 @@ void show_dev_detail(void)
 	 * returned, or which values for them.
 	 */
 	select_channels(sdi);
-	channel_group = lookup_channel_group(sdi);
+	channel_group = lookup_channel_group(sdi, NULL);
 
 	if (!(opts = sr_dev_options(driver, sdi, channel_group)))
 		/* Driver supports no device instance options. */

sigrok-cli.h

@@ -56,7 +56,8 @@ void show_serial_ports(void);
 
 /* device.c */
 GSList *device_scan(void);
-struct sr_channel_group *lookup_channel_group(struct sr_dev_inst *sdi);
+struct sr_channel_group *lookup_channel_group(struct sr_dev_inst *sdi,
+	const char *cg_name);
 
 /* session.c */
 struct df_arg_desc {
@@ -76,6 +77,7 @@ struct df_arg_desc {
 void datafeed_in(const struct sr_dev_inst *sdi,
 		const struct sr_datafeed_packet *packet, void *cb_data);
 int opt_to_gvar(char *key, char *value, struct sr_config *src);
+int set_dev_options_array(struct sr_dev_inst *sdi, char **opts);
 int set_dev_options(struct sr_dev_inst *sdi, GHashTable *args);
 void run_session(void);
 
@@ -129,7 +131,7 @@ extern gboolean opt_wait_trigger;
 extern gchar *opt_input_file;
 extern gchar *opt_output_file;
 extern gchar *opt_drv;
-extern gchar *opt_config;
+extern gchar **opt_configs;
 extern gchar *opt_channels;
 extern gchar *opt_channel_group;
 extern gchar *opt_triggers;