Added bag operations for the high-level control interface.

Added event layer for simple mixer controls (not fully finished).

src/control/bag.c

@@ -0,0 +1,87 @@
+/*
+ *  Control Interface - highlevel API - hcontrol bag operations
+ *  Copyright (c) 2000 by Jaroslav Kysela <perex@suse.cz>
+ *
+ *
+ *   This library is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU Library General Public License as
+ *   published by the Free Software Foundation; either version 2 of
+ *   the License, or (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU Library General Public License for more details.
+ *
+ *   You should have received a copy of the GNU Library General Public
+ *   License along with this library; if not, write to the Free Software
+ *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include <assert.h>
+#define __USE_GNU
+#include <search.h>
+#include "asoundlib.h"
+#include "control_local.h"
+
+int snd_ctl_hbag_create(void **bag)
+{
+	assert(bag != NULL);
+	*bag = NULL;
+	return 0;
+}
+
+static void snd_ctl_hbag_free_private(snd_hcontrol_t *hcontrol ATTRIBUTE_UNUSED)
+{
+	/* nothing */
+}
+
+int snd_ctl_hbag_destroy(void **bag, void (*hcontrol_free)(snd_hcontrol_t *hcontrol))
+{
+	assert(bag != NULL);
+	if (hcontrol_free == NULL)
+		hcontrol_free = snd_ctl_hbag_free_private;
+	tdestroy(*bag, (__free_fn_t)hcontrol_free);
+	*bag = NULL;
+	return 0;
+}
+
+int snd_ctl_hbag_add(void **bag, snd_hcontrol_t *hcontrol)
+{
+	void *res;
+
+	assert(bag != NULL && hcontrol != NULL);
+	res = tsearch(hcontrol, bag, (__compar_fn_t)snd_ctl_hsort);
+	if (res == NULL)
+		return -ENOMEM;
+	if ((snd_hcontrol_t *)res == hcontrol)
+		return -EALREADY;
+	return 0;
+}
+
+int snd_ctl_hbag_del(void **bag, snd_hcontrol_t *hcontrol)
+{
+	assert(bag != NULL && hcontrol != NULL);
+	if (tdelete(hcontrol, bag, (__compar_fn_t)snd_ctl_hsort) == NULL)
+		return -ENOENT;
+	return 0;
+}
+
+snd_hcontrol_t *snd_ctl_hbag_find(void **bag, snd_control_id_t *id)
+{
+	void *res;
+
+	assert(bag != NULL && id != NULL);
+	if (*bag == NULL)
+		return NULL;
+	res = tfind(id, bag, (__compar_fn_t)snd_ctl_hsort);
+	return res == NULL ? NULL : *(snd_hcontrol_t **)res;
+}