Implemented the top-level redirector code for simple mixer

- mixer_abst.c is almost finished (an example module should be created now)
- also fixed some error paths for name function

src/mixer/mixer.c

@@ -497,6 +497,8 @@ int snd_mixer_class_register(snd_mixer_class_t *class, snd_mixer_t *mixer)
  * \brief Unregister mixer element class and remove all its elements
  * \param class Mixer element class
  * \return 0 on success otherwise a negative error code
+ *
+ * Note that the class structure is also deallocated!
  */
 int snd_mixer_class_unregister(snd_mixer_class_t *class)
 {
@@ -929,6 +931,8 @@ int snd_mixer_class_malloc(snd_mixer_class_t **ptr)
  */
 void snd_mixer_class_free(snd_mixer_class_t *obj)
 {
+	if (obj->private_free)
+		obj->private_free(obj);
 	free(obj);
 }
 

src/mixer/simple_abst.c

@@ -34,9 +34,123 @@
 #include <fcntl.h>
 #include <sys/ioctl.h>
 #include <math.h>
-#include "mixer_local.h"
+#include <dlfcn.h>
+#include "config.h"
+#include "asoundlib.h"
 #include "mixer_simple.h"
 
+#define SO_PATH PKGLIBDIR "/smixer/"
+
+typedef struct _class_priv {
+	char *device;
+	snd_ctl_t *ctl;
+	snd_hctl_t *hctl;
+	snd_ctl_card_info_t *info;
+} class_priv_t;   
+
+static int try_open(snd_mixer_class_t *class, const char *lib)
+{
+	snd_mixer_event_t event_func;
+	char *xlib;
+	void *h;
+
+	xlib = malloc(strlen(lib) + strlen(SO_PATH) + 1);
+	if (xlib == NULL)
+		return -ENOMEM;
+	strcpy(xlib, SO_PATH);
+	strcat(xlib, lib);
+	h = snd_dlopen(lib, RTLD_NOW);
+	if (h == NULL) {
+		SNDERR("Unable to open library '%s'", xlib);
+		free(xlib);
+		return -ENXIO;
+	}
+	event_func = dlsym(h, "alsa_mixer_simple_event");
+	if (event_func == NULL) {
+		SNDERR("Symbol 'alsa_mixer_simple_event' was not found in '%s'", xlib);
+		snd_dlclose(h);
+		free(xlib);
+		return -ENXIO;
+	}
+	free(xlib);
+	snd_mixer_class_set_event(class, event_func);
+	return 0;
+}
+
+static int match(snd_mixer_class_t *class, const char *lib, const char *searchl)
+{
+	class_priv_t *priv = snd_mixer_class_get_private(class);
+	const char *components;
+
+	if (searchl == NULL)
+		return try_open(class, lib);
+	components = snd_ctl_card_info_get_components(priv->info);
+	while (*components != '\0') {
+		if (!strncmp(components, searchl, strlen(searchl)))
+			return try_open(class, lib);
+		while (*components != ' ' && *components != '\0')
+			components++;
+		while (*components == ' ' && *components != '\0')
+			components++;
+	}
+	return 0;
+}
+
+static int find_module(snd_mixer_class_t *class, snd_config_t *top)
+{
+	snd_config_iterator_t i, next;
+	snd_config_iterator_t j, jnext;
+	char *lib, *searchl;
+	const char *id;
+	int err;
+
+	snd_config_for_each(i, next, top) {
+		snd_config_t *n = snd_config_iterator_entry(i);
+		if (snd_config_get_id(n, &id) < 0)
+			continue;
+		searchl = NULL;
+		lib = NULL;
+		snd_config_for_each(j, jnext, n) {
+			snd_config_t *m = snd_config_iterator_entry(j);
+			if (snd_config_get_id(m, &id) < 0)
+				continue;
+			if (!strcmp(id, "searchl")) {
+				err = snd_config_get_string(m, (const char **)&searchl);
+				if (err < 0)
+					return err;
+				continue;
+			}
+			if (!strcmp(id, "lib")) {
+				err = snd_config_get_string(m, (const char **)&lib);
+				if (err < 0)
+					return err;
+				continue;
+			}
+		}
+		err = match(class, lib, searchl);
+		if (err == 1)
+			return 0;
+		if (err < 0)
+			return err;
+	}
+	return -ENOENT;
+}
+
+static void private_free(snd_mixer_class_t *class)
+{
+	class_priv_t *priv = snd_mixer_class_get_private(class);
+	
+	if (priv->info)
+		snd_ctl_card_info_free(priv->info);
+	if (priv->hctl)
+		snd_hctl_close(priv->hctl);
+	else if (priv->ctl)
+		snd_ctl_close(priv->ctl);
+	if (priv->device)
+		free(priv->device);
+	free(priv);
+}
+
 /**
  * \brief Register mixer simple element class - basic abstraction
  * \param mixer Mixer handle
@@ -48,29 +162,74 @@ int snd_mixer_simple_basic_register(snd_mixer_t *mixer,
 				    struct snd_mixer_selem_regopt *options,
 				    snd_mixer_class_t **classp)
 {
-	snd_mixer_class_t *class = calloc(1, sizeof(*class));
+	snd_mixer_class_t *class;
+	class_priv_t *priv = calloc(1, sizeof(*priv));
 	const char *file;
 	snd_input_t *input;
+	snd_config_t *top = NULL;
 	int err;
 
-	if (snd_mixer_class_malloc(&class))
+	if (options->device == NULL)
+		return -EIO;
+	if (priv == NULL)
 		return -ENOMEM;
-	//snd_mixer_class_set_event(class, simple_event);
+	if (snd_mixer_class_malloc(&class)) {
+		free(priv);
+		return -ENOMEM;
+	}
+	priv->device = strdup(options->device);
+	if (priv->device == NULL) {
+		free(priv);
+		snd_mixer_class_free(class);
+		return -ENOMEM;
+	}
 	snd_mixer_class_set_compare(class, snd_mixer_selem_compare);
+	snd_mixer_class_set_private(class, priv);
+	snd_mixer_class_set_private_free(class, private_free);
+	err = snd_ctl_open(&priv->ctl, priv->device, 0);
+	if (err < 0) {
+		SNDERR("unable to open control device '%s': %s", priv->device, snd_strerror(err));
+		goto __error;
+	}
+	err = snd_hctl_open_ctl(&priv->hctl, priv->ctl);
+	if (err < 0)
+		goto __error;
+	err = snd_ctl_card_info_malloc(&priv->info);
+	if (err < 0)
+		goto __error;
+	err = snd_ctl_card_info(priv->ctl, priv->info);
+	if (err < 0)
+		goto __error;
 	file = getenv("ALSA_MIXER_SIMPLE");
 	if (!file)
 		file = DATADIR "/alsa/smixer.conf";
-	if ((err = snd_input_stdio_open(&input, file, "r")) < 0) {
-		SNDERR("unable to open simple mixer configuration file '%s'", file);
-		goto __error;
+	err = snd_config_top(&top);
+	if (err >= 0) {
+		err = snd_input_stdio_open(&input, file, "r");
+		if (err < 0) {
+			SNDERR("unable to open simple mixer configuration file '%s'", file);
+			goto __error;
+		}
+		err = snd_config_load(top, input);
+		snd_input_close(input);
+		if (err < 0) {
+			SNDERR("%s may be old or corrupted: consider to remove or fix it", file);
+			goto __error;
+		}
+		err = find_module(class, top);
 	}
-	err = snd_mixer_class_register(class, mixer);
+	if (err >= 0)
+		err = snd_mixer_class_register(class, mixer);
 	if (err < 0) {
 	      __error:
+	      	if (top)
+	      		snd_config_delete(top);
 	      	if (class)
 			snd_mixer_class_free(class);
 		return err;
 	}
+	if (top)
+		snd_config_delete(top);
 	if (classp)
 		*classp = class;
 	return 0;

src/names.c

@@ -75,6 +75,7 @@ static int names_parse(snd_config_t *top, const char *iface, snd_devname_t **lis
 					err = -ENOMEM;
 					goto _err;
 				}
+				continue;
 			}
 			if (strcmp(id, "comment") == 0) {
 				err = snd_config_get_string(m, (const char **)&comment);
@@ -85,6 +86,7 @@ static int names_parse(snd_config_t *top, const char *iface, snd_devname_t **lis
 					err = -ENOMEM;
 					goto _err;
 				}
+				continue;
 			}
 		}
 		if (name != NULL) {
@@ -151,6 +153,7 @@ int snd_names_list(const char *iface, snd_devname_t **list)
 				return -ENOMEM;
 		}
 	}
+	top = NULL;
 	err = snd_config_top(&top);
 	if (err >= 0)
 		err = snd_input_stdio_open(&in, file, "r");
@@ -169,7 +172,8 @@ int snd_names_list(const char *iface, snd_devname_t **list)
 	} else {
 		SNDERR("cannot access file %s", file);
 	}
-	snd_config_delete(top);
+	if (top)
+		snd_config_delete(top);
 	return err >= 0 ? 0 : err;
 }