The highlevel control layer was rewritten and updated.

Various fixes in mixer simple layer.
Added include/list.h (from the kernel tree).

7 files changed, 371 insertions, 178 deletions

diff --git a/include/control.h b/include/control.h
index a7c99d4c..af1eba9b 100644
--- a/include/control.h
+++ b/include/control.h
@@ -54,10 +54,25 @@ int snd_ctl_read(snd_ctl_t *handle, snd_ctl_callbacks_t * callbacks);
  *  Highlevel API for controls
  */
 
+#define LIST_HEAD_IS_DEFINED
+struct list_head {
+        struct list_head *next, *prev;
+};        
+
+typedef struct snd_hcontrol_list_stru snd_hcontrol_list_t;
 typedef struct snd_hcontrol_stru snd_hcontrol_t;
 
+struct snd_hcontrol_list_stru {
+	unsigned int controls_offset;	/* W: first control ID to get */
+	unsigned int controls_request;	/* W: count of control IDs to get */
+	unsigned int controls_count;	/* R: count of available (set) controls */
+	unsigned int controls;		/* R: count of all available controls */
+	snd_control_id_t *pids;		/* W: IDs */
+};
+
 struct snd_hcontrol_stru {
 	snd_control_id_t id; 	/* must be always on top */
+	struct list_head list;	/* links for list of all hcontrols */
 	int change: 1,		/* structure change */
 	    value: 1;		/* value change */
 	/* event callbacks */
@@ -71,18 +86,19 @@ struct snd_hcontrol_stru {
 	snd_ctl_t *handle;	/* associated handle */
 };
 
-typedef int (snd_ctl_csort_t)(const snd_hcontrol_t *c1, const snd_hcontrol_t *c2);
-typedef int (snd_ctl_ccallback_rebuild_t)(snd_ctl_t *handle, void *private_data);
-typedef int (snd_ctl_ccallback_add_t)(snd_ctl_t *handle, void *private_data, snd_hcontrol_t *hcontrol);
-
-int snd_ctl_cbuild(snd_ctl_t *handle, snd_ctl_csort_t *csort);
-int snd_ctl_cfree(snd_ctl_t *handle);
-snd_hcontrol_t *snd_ctl_cfind(snd_ctl_t *handle, snd_control_id_t *id);
-int snd_ctl_csort(const snd_hcontrol_t *c1, const snd_hcontrol_t *c2);
-int snd_ctl_cresort(snd_ctl_t *handle, snd_ctl_csort_t *csort);
-int snd_ctl_ccallback_rebuild(snd_ctl_t *handle, snd_ctl_ccallback_rebuild_t *callback, void *private_data);
-int snd_ctl_ccallback_add(snd_ctl_t *handle, snd_ctl_ccallback_add_t *callback, void *private_data);
-int snd_ctl_cevent(snd_ctl_t *handle);
+typedef int (snd_ctl_hsort_t)(const snd_hcontrol_t *c1, const snd_hcontrol_t *c2);
+typedef int (snd_ctl_hcallback_rebuild_t)(snd_ctl_t *handle, void *private_data);
+typedef int (snd_ctl_hcallback_add_t)(snd_ctl_t *handle, void *private_data, snd_hcontrol_t *hcontrol);
+
+int snd_ctl_hbuild(snd_ctl_t *handle, snd_ctl_hsort_t *csort);
+int snd_ctl_hfree(snd_ctl_t *handle);
+snd_hcontrol_t *snd_ctl_hfind(snd_ctl_t *handle, snd_control_id_t *id);
+int snd_ctl_hlist(snd_ctl_t *handle, snd_hcontrol_list_t *hlist);
+int snd_ctl_hsort(const snd_hcontrol_t *c1, const snd_hcontrol_t *c2);
+int snd_ctl_hresort(snd_ctl_t *handle, snd_ctl_hsort_t *csort);
+int snd_ctl_hcallback_rebuild(snd_ctl_t *handle, snd_ctl_hcallback_rebuild_t *callback, void *private_data);
+int snd_ctl_hcallback_add(snd_ctl_t *handle, snd_ctl_hcallback_add_t *callback, void *private_data);
+int snd_ctl_hevent(snd_ctl_t *handle);
 
 #ifdef __cplusplus
 }
diff --git a/include/list.h b/include/list.h
new file mode 100644
index 00000000..320dbf16
--- /dev/null
+++ b/include/list.h
@@ -0,0 +1,156 @@
+#ifndef _LIST_H
+#define _LIST_H
+
+/*
+ * This code was taken from the Linux 2.4.0 kernel. [jaroslav]
+ */
+
+/*
+ * Simple doubly linked list implementation.
+ *
+ * Some of the internal functions ("__xxx") are useful when
+ * manipulating whole lists rather than single entries, as
+ * sometimes we already know the next/prev entries and we can
+ * generate better code by using them directly rather than
+ * using the generic single-entry routines.
+ */
+
+#ifndef LIST_HEAD_IS_DEFINED
+struct list_head {
+	struct list_head *next, *prev;
+};
+#endif
+
+#define LIST_HEAD_INIT(name) { &(name), &(name) }
+
+#define LIST_HEAD(name) \
+	struct list_head name = LIST_HEAD_INIT(name)
+
+#define INIT_LIST_HEAD(ptr) do { \
+	(ptr)->next = (ptr); (ptr)->prev = (ptr); \
+} while (0)
+
+/*
+ * Insert a new entry between two known consecutive entries. 
+ *
+ * This is only for internal list manipulation where we know
+ * the prev/next entries already!
+ */
+static __inline__ void __list_add(struct list_head * new,
+	struct list_head * prev,
+	struct list_head * next)
+{
+	next->prev = new;
+	new->next = next;
+	new->prev = prev;
+	prev->next = new;
+}
+
+/**
+ * list_add - add a new entry
+ * @new: new entry to be added
+ * @head: list head to add it after
+ *
+ * Insert a new entry after the specified head.
+ * This is good for implementing stacks.
+ */
+static __inline__ void list_add(struct list_head *new, struct list_head *head)
+{
+	__list_add(new, head, head->next);
+}
+
+/**
+ * list_add_tail - add a new entry
+ * @new: new entry to be added
+ * @head: list head to add it before
+ *
+ * Insert a new entry before the specified head.
+ * This is useful for implementing queues.
+ */
+static __inline__ void list_add_tail(struct list_head *new, struct list_head *head)
+{
+	__list_add(new, head->prev, head);
+}
+
+/*
+ * Delete a list entry by making the prev/next entries
+ * point to each other.
+ *
+ * This is only for internal list manipulation where we know
+ * the prev/next entries already!
+ */
+static __inline__ void __list_del(struct list_head * prev,
+				  struct list_head * next)
+{
+	next->prev = prev;
+	prev->next = next;
+}
+
+/**
+ * list_del - deletes entry from list.
+ * @entry: the element to delete from the list.
+ * Note: list_empty on entry does not return true after this, the entry is in an undefined state.
+ */
+static __inline__ void list_del(struct list_head *entry)
+{
+	__list_del(entry->prev, entry->next);
+}
+
+/**
+ * list_del_init - deletes entry from list and reinitialize it.
+ * @entry: the element to delete from the list.n 
+ */
+static __inline__ void list_del_init(struct list_head *entry)
+{
+	__list_del(entry->prev, entry->next);
+	INIT_LIST_HEAD(entry); 
+}
+
+/**
+ * list_empty - tests whether a list is empty
+ * @head: the list to test.
+ */
+static __inline__ int list_empty(struct list_head *head)
+{
+	return head->next == head;
+}
+
+/**
+ * list_splice - join two lists
+ * @list: the new list to add.
+ * @head: the place to add it in the first list.
+ */
+static __inline__ void list_splice(struct list_head *list, struct list_head *head)
+{
+	struct list_head *first = list->next;
+
+	if (first != list) {
+		struct list_head *last = list->prev;
+		struct list_head *at = head->next;
+
+		first->prev = head;
+		head->next = first;
+
+		last->next = at;
+		at->prev = last;
+	}
+}
+
+/**
+ * list_entry - get the struct for this entry
+ * @ptr:	the &struct list_head pointer.
+ * @type:	the type of the struct this is embedded in.
+ * @member:	the name of the list_struct within the struct.
+ */
+#define list_entry(ptr, type, member) \
+	((type *)((char *)(ptr)-(unsigned long)(&((type *)0)->member)))
+
+/**
+ * list_for_each	-	iterate over a list
+ * @pos:	the &struct list_head to use as a loop counter.
+ * @head:	the head for your list.
+ */
+#define list_for_each(pos, head) \
+	for (pos = (head)->next; pos != (head); pos = pos->next)
+
+#endif /* _LIST_H */
diff --git a/src/control/control.c b/src/control/control.c
index 9a14c3d9..5c3dcfb8 100644
--- a/src/control/control.c
+++ b/src/control/control.c
@@ -64,6 +64,7 @@ int snd_ctl_open(snd_ctl_t **handle, int card)
 	}
 	ctl->card = card;
 	ctl->fd = fd;
+	INIT_LIST_HEAD(&ctl->hlist);
 	*handle = ctl;
 	return 0;
 }
@@ -101,7 +102,7 @@ int snd_ctl_clist(snd_ctl_t *handle, snd_control_list_t *list)
 
 int snd_ctl_cinfo(snd_ctl_t *handle, snd_control_info_t *info)
 {
-	assert(handle && info && info->id.name[0]);
+	assert(handle && info && (info->id.name[0] || info->id.numid));
 	if (ioctl(handle->fd, SND_CTL_IOCTL_CONTROL_INFO, info) < 0)
 		return -errno;
 	return 0;
@@ -109,7 +110,7 @@ int snd_ctl_cinfo(snd_ctl_t *handle, snd_control_info_t *info)
 
 int snd_ctl_cread(snd_ctl_t *handle, snd_control_t *control)
 {
-	assert(handle && control && control->id.name[0]);
+	assert(handle && control && (control->id.name[0] || control->id.numid));
 	if (ioctl(handle->fd, SND_CTL_IOCTL_CONTROL_READ, control) < 0)
 		return -errno;
 	return 0;
@@ -117,7 +118,7 @@ int snd_ctl_cread(snd_ctl_t *handle, snd_control_t *control)
 
 int snd_ctl_cwrite(snd_ctl_t *handle, snd_control_t *control)
 {
-	assert(handle && control && control->id.name[0]);
+	assert(handle && control && (control->id.name[0] || control->id.numid));
 	if (ioctl(handle->fd, SND_CTL_IOCTL_CONTROL_WRITE, control) < 0)
 		return -errno;
 	return 0;
diff --git a/src/control/control_local.h b/src/control/control_local.h
index d6e12531..4c2e826c 100644
--- a/src/control/control_local.h
+++ b/src/control/control_local.h
@@ -19,16 +19,19 @@
  *
  */
 
+#include "list.h"
+
 struct snd_ctl {
 	int card;
 	int fd;
-	int ccount;
-	int cerr;
-	void *croot;		/* root of controls */
-	void *croot_new;	/* new croot */
-	snd_ctl_csort_t *csort;
-	snd_ctl_ccallback_rebuild_t *callback_rebuild;
+	int hcount;
+	int herr;
+	struct list_head hlist;	/* list of all controls */
+	void *hroot;		/* root of controls */
+	void *hroot_new;	/* new croot */
+	snd_ctl_hsort_t *hsort;
+	snd_ctl_hcallback_rebuild_t *callback_rebuild;
 	void *callback_rebuild_private_data;
-	snd_ctl_ccallback_add_t *callback_add;
+	snd_ctl_hcallback_add_t *callback_add;
 	void *callback_add_private_data;
 };
diff --git a/src/control/controls.c b/src/control/controls.c
index 7b53515b..9a169423 100644
--- a/src/control/controls.c
+++ b/src/control/controls.c
@@ -32,21 +32,20 @@
 #include "asoundlib.h"
 #include "control_local.h"
 
-static void snd_ctl_cfree1(snd_hcontrol_t *hcontrol);
+static void snd_ctl_hfree1(snd_hcontrol_t *hcontrol);
 
-int snd_ctl_cbuild(snd_ctl_t *handle, snd_ctl_csort_t *csort)
+int snd_ctl_hbuild(snd_ctl_t *handle, snd_ctl_hsort_t *hsort)
 {
 	snd_control_list_t list;
 	snd_hcontrol_t *hcontrol, *prev;
 	int err;
 	unsigned int idx;
 
-	printf("cbuild - start\n");
 	assert(handle != NULL);
-	if ((err = snd_ctl_cfree(handle)) < 0)
+	if ((err = snd_ctl_hfree(handle)) < 0)
 		return err;
-	if (csort == NULL)
-		csort = snd_ctl_csort;
+	if (hsort == NULL)
+		hsort = snd_ctl_hsort;
 	memset(&list, 0, sizeof(list));
 	do {
 		if (list.pids != NULL)
@@ -67,132 +66,171 @@ int snd_ctl_cbuild(snd_ctl_t *handle, snd_ctl_csort_t *csort)
 	} while (list.controls != list.controls_count);
 	for (idx = 0, prev = NULL; idx < list.controls_count; idx++) {
 		hcontrol = (snd_hcontrol_t *)calloc(1, sizeof(snd_hcontrol_t));
-		if (hcontrol == NULL) {
-			snd_ctl_cfree(handle);
-			free(list.pids);
-			return -ENOMEM;
-		}
+		if (hcontrol == NULL)
+			goto __nomem;
 		hcontrol->id = list.pids[idx];
 		hcontrol->handle = handle;
-		if (tsearch(hcontrol, &handle->croot, (__compar_fn_t)csort) == NULL) {
-			tdestroy(&handle->croot, (__free_fn_t)snd_ctl_cfree1);
-			handle->croot = NULL;
+		if (tsearch(hcontrol, &handle->hroot, (__compar_fn_t)hsort) == NULL) {
+		      __nomem:
+			if (handle->hroot != NULL) {
+				tdestroy(handle->hroot, (__free_fn_t)snd_ctl_hfree1);
+				handle->hroot = NULL;
+			}
+			handle->hroot = NULL;
+			if (hcontrol != NULL)
+				free(hcontrol);
+			free(list.pids);
+			return -ENOMEM;
 		}
-		handle->ccount++;
+		list_add_tail(&hcontrol->list, &handle->hlist);
+		handle->hcount++;
 	}
 	if (list.pids != NULL)
 		free(list.pids);
-	handle->csort = csort;
+	if ((err = snd_ctl_hresort(handle, hsort)) < 0) {
+		tdestroy(handle->hroot, (__free_fn_t)snd_ctl_hfree1);
+		handle->hroot = NULL;
+	}
 	return 0;
 }
 
-static void snd_ctl_cfree1(snd_hcontrol_t *hcontrol)
+static void snd_ctl_hfree1(snd_hcontrol_t *hcontrol)
 {
 	snd_ctl_t *handle;
 	
 	assert(hcontrol != NULL);
 	handle = hcontrol->handle;
 	assert(handle != NULL);
-	assert(handle->ccount > 0);
+	assert(handle->hcount > 0);
 	if (hcontrol->event_remove)
 		hcontrol->event_remove(handle, hcontrol);
 	if (hcontrol->private_free)
 		hcontrol->private_free(hcontrol->private_data);
+	list_del(&hcontrol->list);
 	free(hcontrol);
-	handle->ccount--;
+	handle->hcount--;
 }
 
-int snd_ctl_cfree(snd_ctl_t *handle)
+int snd_ctl_hfree(snd_ctl_t *handle)
 {
-	handle->csort = NULL;
-	handle->cerr = 0;
-	if (handle->croot != NULL) {
-		tdestroy(handle->croot, (__free_fn_t)snd_ctl_cfree1);
-		handle->croot = NULL;
+	handle->hsort = NULL;
+	handle->herr = 0;
+	if (handle->hroot != NULL) {
+		tdestroy(handle->hroot, (__free_fn_t)snd_ctl_hfree1);
+		handle->hroot = NULL;
 	}
-	assert(handle->ccount == 0);
+	assert(list_empty(&handle->hlist));
+	assert(handle->hcount == 0);
 	return 0;
 }
 
-int snd_ctl_csort(const snd_hcontrol_t *c1, const snd_hcontrol_t *c2)
+int snd_ctl_hsort(const snd_hcontrol_t *c1, const snd_hcontrol_t *c2)
 {
 	int res;
 
-	res = strcmp(c1->id.name, c2->id.name);
-	if (res == 0) {
-		if (c1->id.index < c2->id.index)
-			return -1;
-		if (c1->id.index > c2->id.index)
-			return 1;
-		return 0;
-	}
-	return res;
-}
-
-static void snd_ctl_cresort_action(snd_hcontrol_t *hcontrol, VISIT which, int level)
-{
-	snd_ctl_t *handle;
-
-	level = 0;			/* to keep GCC happy */
-	assert(hcontrol != NULL);
-	handle = hcontrol->handle;
-	assert(handle != NULL);
-	if (handle->cerr < 0)
-		return;
-	switch (which) {
-	case preorder: break;
-	case postorder: break;
-	case endorder:
-	case leaf:
-		if (tsearch(hcontrol, &handle->croot, (__compar_fn_t)handle->csort) == NULL)
-			handle->cerr = -ENOMEM;
-		break;
-	}
+	if (c1->id.iface < c2->id.iface)
+		return -1;
+	if (c1->id.iface > c2->id.iface)
+		return 1;
+	if ((res = strcmp(c1->id.name, c2->id.name)) != 0)
+		return res;
+	if (c1->id.index < c2->id.index)
+		return -1;
+	if (c1->id.index > c2->id.index)
+		return 1;
+	return 0;
 }
 
-static void snd_ctl_cresort_free(snd_hcontrol_t *hcontrol)
+static void snd_ctl_hresort_free(snd_hcontrol_t *hcontrol ATTRIBUTE_UNUSED)
 {
-	hcontrol = NULL;		/* to keep GCC happy */
 	/* nothing */
 }
 
-int snd_ctl_cresort(snd_ctl_t *handle, snd_ctl_csort_t *csort)
+int snd_ctl_hresort(snd_ctl_t *handle, snd_ctl_hsort_t *hsort)
 {
-	int result;
-	snd_ctl_csort_t *csort_old;
+	struct list_head *list;
+	snd_hcontrol_t *hcontrol;
+	snd_control_id_t *ids, *pids;
+	int idx;
 
-	assert(handle != NULL && csort != NULL);
-	if (handle->ccount == 0)
+	assert(handle != NULL && hsort != NULL);
+	if (handle->hcount == 0)
 		return 0;
-	if (handle->cerr < 0)
-		return handle->cerr;
-	assert(handle->croot_new == NULL);
-	csort_old = handle->csort;
-	handle->csort = csort;
-	twalk(handle->croot, (__action_fn_t)snd_ctl_cresort_action);
-	if (handle->cerr < 0) {
-		result = handle->cerr;
-		handle->cerr = 0;
-		handle->csort = csort_old;
-		tdestroy(handle->croot_new, (__free_fn_t)snd_ctl_cresort_free);
-		handle->croot_new = NULL;
-		return result;
+	if (handle->herr < 0)
+		return handle->herr;
+	assert(handle->hroot_new == NULL);
+	ids = pids = (snd_control_id_t *)malloc(sizeof(snd_control_id_t) * handle->hcount);
+	if (ids == NULL)
+		return -ENOMEM;
+	/* first step - update search engine */
+	list_for_each(list, &handle->hlist) {
+		hcontrol = list_entry(list, snd_hcontrol_t, list);
+		*pids++ = hcontrol->id;
+		if (tsearch(hcontrol, &handle->hroot_new, (__compar_fn_t)hsort) == NULL) {
+			if (handle->hroot_new != NULL)
+				tdestroy(handle->hroot_new, (__free_fn_t)snd_ctl_hresort_free);
+			handle->hroot_new = NULL;
+			free(ids);
+			return -ENOMEM;
+		}
 	}
-	tdestroy(handle->croot, (__free_fn_t)snd_ctl_cresort_free);
-	handle->croot = handle->croot_new;
-	handle->croot_new = NULL;
+	if (handle->hroot != NULL)
+		tdestroy(handle->hroot, (__free_fn_t)snd_ctl_hresort_free);
+	handle->hsort = hsort;
+	handle->hroot = handle->hroot_new;
+	handle->hroot_new = NULL;
+	/* second step - perform qsort and save results */
+	qsort(ids, handle->hcount, sizeof(snd_control_id_t), (int (*)(const void *, const void *))hsort);
+	INIT_LIST_HEAD(&handle->hlist);
+	for (idx = 0; idx < handle->hcount; idx++) {
+		hcontrol = snd_ctl_hfind(handle, ids + idx);
+		list_add_tail(&hcontrol->list, &handle->hlist);
+	}
+	free(ids);
 	return 0;
 }
 
-snd_hcontrol_t *snd_ctl_cfind(snd_ctl_t *handle, snd_control_id_t *id)
+snd_hcontrol_t *snd_ctl_hfind(snd_ctl_t *handle, snd_control_id_t *id)
 {
+	void *res;
+
 	assert(handle != NULL);
-	if (handle->croot == NULL)
+	if (handle->hroot == NULL)
 		return NULL;
-	return (snd_hcontrol_t *)tfind(id, &handle->croot, (__compar_fn_t)handle->csort);
+	res = tfind(id, &handle->hroot, (__compar_fn_t)handle->hsort);
+	return res == NULL ? NULL : *(snd_hcontrol_t **)res;
+}
+
+int snd_ctl_hlist(snd_ctl_t *handle, snd_hcontrol_list_t *hlist)
+{
+	struct list_head *list;
+	snd_hcontrol_t *hcontrol;
+	unsigned int idx;
+
+	assert(hlist != NULL);
+	if (hlist->controls_offset >= (unsigned int)handle->hcount)
+		return -EINVAL;
+	hlist->controls_count = 0;
+	hlist->controls = handle->hcount;
+	if (hlist->controls_request > 0) {
+		if (hlist->pids == NULL)
+			return -EINVAL;
+		idx = 0;
+		list_for_each(list, &handle->hlist) {
+			hcontrol = list_entry(list, snd_hcontrol_t, list);
+			if (idx >= hlist->controls_offset + hlist->controls_request)
+				break;
+			if (idx >= hlist->controls_offset) {
+				hlist->pids[idx] = hcontrol->id;
+				hlist->controls_count++;
+			}
+			idx++;
+		}
+	}
+	return 0;
 }
 
-int snd_ctl_ccallback_rebuild(snd_ctl_t *handle, snd_ctl_ccallback_rebuild_t *callback, void *private_data)
+int snd_ctl_hcallback_rebuild(snd_ctl_t *handle, snd_ctl_hcallback_rebuild_t *callback, void *private_data)
 {
 	assert(handle != NULL);
 	handle->callback_rebuild = callback;
@@ -200,7 +238,7 @@ int snd_ctl_ccallback_rebuild(snd_ctl_t *handle, snd_ctl_ccallback_rebuild_t *ca
 	return 0;
 }
 
-int snd_ctl_ccallback_add(snd_ctl_t *handle, snd_ctl_ccallback_add_t *callback, void *private_data)
+int snd_ctl_hcallback_add(snd_ctl_t *handle, snd_ctl_hcallback_add_t *callback, void *private_data)
 {
 	assert(handle != NULL);
 	handle->callback_add = callback;
@@ -208,110 +246,85 @@ int snd_ctl_ccallback_add(snd_ctl_t *handle, snd_ctl_ccallback_add_t *callback,
 	return 0;
 }
 
-static void callback_rebuild(snd_ctl_t *handle, void *private_data)
+static void callback_rebuild(snd_ctl_t *handle, void *private_data ATTRIBUTE_UNUSED)
 {
-	private_data = NULL;	/* to keep GCC happy */
-	handle->cerr = snd_ctl_cbuild(handle, handle->csort);
-	if (handle->cerr >= 0 && handle->callback_rebuild)
+	handle->herr = snd_ctl_hbuild(handle, handle->hsort);
+	if (handle->herr >= 0 && handle->callback_rebuild)
 		handle->callback_rebuild(handle, handle->callback_rebuild_private_data);
 }
 
-static void callback_change(snd_ctl_t *handle, void *private_data, snd_control_id_t *id)
+static void callback_change(snd_ctl_t *handle, void *private_data ATTRIBUTE_UNUSED, snd_control_id_t *id)
 {
 	snd_hcontrol_t *hcontrol;
 
-	private_data = NULL;	/* to keep GCC happy */
-	if (handle->cerr < 0)
+	if (handle->herr < 0)
 		return;
-	hcontrol = snd_ctl_cfind(handle, id);
+	hcontrol = snd_ctl_hfind(handle, id);
 	if (hcontrol == NULL) {
-		handle->cerr = -ENOENT;
+		handle->herr = -ENOENT;
 		return;
 	}
 	hcontrol->change = 1;
 }
 
-static void callback_value(snd_ctl_t *handle, void *private_data, snd_control_id_t *id)
+static void callback_value(snd_ctl_t *handle, void *private_data ATTRIBUTE_UNUSED, snd_control_id_t *id)
 {
 	snd_hcontrol_t *hcontrol;
 
-	private_data = NULL;	/* to keep GCC happy */
-	if (handle->cerr < 0)
+	if (handle->herr < 0)
 		return;
-	hcontrol = snd_ctl_cfind(handle, id);
+	hcontrol = snd_ctl_hfind(handle, id);
 	if (hcontrol == NULL) {
-		handle->cerr = -ENOENT;
+		handle->herr = -ENOENT;
 		return;
 	}
 	hcontrol->value = 1;
 }
 
-static void callback_add(snd_ctl_t *handle, void *private_data, snd_control_id_t *id)
+static void callback_add(snd_ctl_t *handle, void *private_data ATTRIBUTE_UNUSED, snd_control_id_t *id)
 {
 	snd_hcontrol_t *hcontrol, *icontrol;
 
-	private_data = NULL;	/* to keep GCC happy */
-	if (handle->cerr < 0)
+	if (handle->herr < 0)
 		return;
 	hcontrol = (snd_hcontrol_t *)calloc(1, sizeof(snd_hcontrol_t));
 	if (hcontrol == NULL) {
-		handle->cerr = -ENOMEM;
+		handle->herr = -ENOMEM;
 		return;
 	}
 	hcontrol->id = *id;
 	hcontrol->handle = handle;
-	icontrol = tsearch(hcontrol, &handle->croot, (__compar_fn_t)handle->csort);
+	icontrol = tsearch(hcontrol, &handle->hroot, (__compar_fn_t)handle->hsort);
 	if (icontrol == NULL) {
 		free(hcontrol);
-		handle->cerr = -ENOMEM;
+		handle->herr = -ENOMEM;
 		return;
 	}
 	if (icontrol != hcontrol) {	/* double hit */
 		free(hcontrol);
 		return;
 	}
+	list_add_tail(&hcontrol->list, &handle->hlist);
 	if (handle->callback_add)
 		handle->callback_add(handle, handle->callback_add_private_data, hcontrol);
 }
 
-static void callback_remove(snd_ctl_t *handle, void *private_data, snd_control_id_t *id)
+static void callback_remove(snd_ctl_t *handle, void *private_data ATTRIBUTE_UNUSED, snd_control_id_t *id)
 {
 	snd_hcontrol_t *hcontrol;
 
-	private_data = NULL;	/* to keep GCC happy */
-	if (handle->cerr < 0)
+	if (handle->herr < 0)
 		return;
-	hcontrol = snd_ctl_cfind(handle, id);
+	hcontrol = snd_ctl_hfind(handle, id);
 	if (hcontrol == NULL) {
-		handle->cerr = -ENOENT;
+		handle->herr = -ENOENT;
 		return;
 	}
-	if (tdelete(hcontrol, &handle->croot, (__compar_fn_t)handle->csort) != NULL)
-		snd_ctl_cfree1(hcontrol);
+	if (tdelete(hcontrol, &handle->hroot, (__compar_fn_t)handle->hsort) != NULL)
+		snd_ctl_hfree1(hcontrol);
 }
 
-static void snd_ctl_cevent_walk1(snd_hcontrol_t *hcontrol, VISIT which, int level)
-{
-	level = 0;	/* to keep GCC happy */
-	assert(hcontrol != NULL);
-	switch (which) {
-	case preorder: break;
-	case postorder: break;
-	case endorder:
-	case leaf:
-		if (hcontrol->change && hcontrol->event_change) {
-			hcontrol->event_change(hcontrol->handle, hcontrol);
-			hcontrol->change = 0;
-		}
-		if (hcontrol->value && hcontrol->event_value) {
-			hcontrol->event_value(hcontrol->handle, hcontrol);
-			hcontrol->value = 0;
-		}			
-		break;
-	}
-}
-
-int snd_ctl_cevent(snd_ctl_t *handle)
+int snd_ctl_hevent(snd_ctl_t *handle)
 {
 	static snd_ctl_callbacks_t callbacks = {
 		rebuild: callback_rebuild,
@@ -322,15 +335,27 @@ int snd_ctl_cevent(snd_ctl_t *handle)
 		private_data: NULL,
 		reserved: { NULL, }
 	};
+	struct list_head *list;
+	snd_hcontrol_t *hcontrol;
 	int res;
 
 	assert(handle != NULL);
-	handle->cerr = 0;
+	handle->herr = 0;
 	res = snd_ctl_read(handle, &callbacks);
 	if (res < 0)
 		return res;
-	if (handle->cerr < 0)
-		return handle->cerr;
-	twalk(handle->croot, (__action_fn_t)snd_ctl_cevent_walk1);
+	if (handle->herr < 0)
+		return handle->herr;
+	list_for_each(list, &handle->hlist) {
+		hcontrol = list_entry(list, snd_hcontrol_t, list);
+		if (hcontrol->change && hcontrol->event_change) {
+			hcontrol->event_change(hcontrol->handle, hcontrol);
+			hcontrol->change = 0;
+		}
+		if (hcontrol->value && hcontrol->event_value) {
+			hcontrol->event_value(hcontrol->handle, hcontrol);
+			hcontrol->value = 0;
+		}			
+	}
 	return res;
 }
diff --git a/src/mixer/mixer.c b/src/mixer/mixer.c
index 1c9f27c1..4e5b4e8c 100644
--- a/src/mixer/mixer.c
+++ b/src/mixer/mixer.c
@@ -214,7 +214,7 @@ int snd_mixer_simple_read(snd_mixer_t *handle, snd_mixer_simple_callbacks_t *cal
 		snd_mixer_simple_build(handle);
 	handle->callbacks = callbacks;
 	handle->simple_changes = 0;
-	if ((err = snd_ctl_cevent(handle->ctl_handle)) <= 0) {
+	if ((err = snd_ctl_hevent(handle->ctl_handle)) <= 0) {
 		handle->callbacks = NULL;
 		return err;
 	}
diff --git a/src/mixer/simple.c b/src/mixer/simple.c
index f9e4bfc7..4a7c15f8 100644
--- a/src/mixer/simple.c
+++ b/src/mixer/simple.c
@@ -38,9 +38,8 @@ static int test_mixer_id(snd_mixer_t *handle, const char *name, int index)
 	id.iface = SND_CONTROL_IFACE_MIXER;
 	strcpy(id.name, name);
 	id.index = index;
-	printf("look\n");
-	hcontrol = snd_ctl_cfind(handle->ctl_handle, &id);
-	fprintf(stderr, "Looking for control: '%s', %i (0x%lx)\n", name, index, (long)hcontrol);
+	hcontrol = snd_ctl_hfind(handle->ctl_handle, &id);
+	// fprintf(stderr, "Looking for control: '%s', %i (0x%lx)\n", name, index, (long)hcontrol);
 	return hcontrol != NULL;
 }
 
@@ -339,19 +338,15 @@ static int build_input(snd_mixer_t *handle, const char *sname)
 	memset(&gvolume_info, 0, sizeof(gvolume_info));
 	memset(&pvolume_info, 0, sizeof(pvolume_info));
 	memset(&cvolume_info, 0, sizeof(cvolume_info));
-	printf("b (1)\n");
-	do {
+	while (1) {
 		index++;
 		voices = 0;
 		present = caps = capture_item = 0;
 		min = max = 0;
 		sprintf(str, "%s Switch", sname);
-		printf("b (2)\n");
 		if (test_mixer_id(handle, str, index)) {
-			printf("b (3)\n");
 			if ((err = get_mixer_info(handle, str, index, &gswitch_info)) < 0)
 				return err;
-			printf("b (4)\n");
 			if (gswitch_info.type == SND_CONTROL_TYPE_BOOLEAN) {
 				if (voices < gswitch_info.values_count)
 					voices = gswitch_info.values_count;
@@ -359,7 +354,6 @@ static int build_input(snd_mixer_t *handle, const char *sname)
 				present |= MIXER_PRESENT_GLOBAL_SWITCH;
 			}
 		}
-		printf("b (3)\n");
 		sprintf(str, "%s Volume", sname);
 		if (test_mixer_id(handle, str, index)) {
 			if ((err = get_mixer_info(handle, str, index, &gvolume_info)) < 0)
@@ -483,7 +477,8 @@ static int build_input(snd_mixer_t *handle, const char *sname)
 					caps &= ~SND_MIXER_SCTCAP_JOINTLY_VOLUME;
 			}
 		}
-		printf("b (4)\n");
+		if (present == 0)
+			break;
 		simple = build_input_scontrol(handle, sname, index);
 		if (simple == NULL)
 			return -ENOMEM;
@@ -500,8 +495,8 @@ static int build_input(snd_mixer_t *handle, const char *sname)
 		simple->voices = voices;
 		simple->min = min;
 		simple->max = max;
-		fprintf(stderr, "sname = '%s', index = %i, present = 0x%x, voices = %i\n", sname, index, present, voices);
-	} while (present != 0);
+		// fprintf(stderr, "sname = '%s', index = %i, present = 0x%x, voices = %i\n", sname, index, present, voices);
+	};
 	return 0;
 }
 
@@ -527,11 +522,9 @@ int snd_mixer_simple_build(snd_mixer_t *handle)
 	char **input = inputs;
 	int err;
 
-	printf("simple build - start\n");
-	if ((err = snd_ctl_cbuild(handle->ctl_handle, snd_ctl_csort)) < 0)
+	if ((err = snd_ctl_hbuild(handle->ctl_handle, snd_ctl_hsort)) < 0)
 		return err;
 	while (*input) {
-		printf("simple build - input '%s'\n", *input);
 		if ((err = build_input(handle, *input)) < 0) {
 			snd_mixer_simple_destroy(handle);
 			return err;
@@ -539,7 +532,6 @@ int snd_mixer_simple_build(snd_mixer_t *handle)
 		input++;
 	}
 	handle->simple_valid = 1;
-	printf("simple build - end\n");
 	return 0;
 }
 
@@ -548,6 +540,6 @@ int snd_mixer_simple_destroy(snd_mixer_t *handle)
 	while (handle->simple_first)
 		simple_remove(handle, handle->simple_first);
 	handle->simple_valid = 0;
-	snd_ctl_cfree(handle->ctl_handle);
+	snd_ctl_hfree(handle->ctl_handle);
 	return 0;
 }