From 5bb1fcb00ae2661e8b501437021cd96a74d1ca2c Mon Sep 17 00:00:00 2001
From: Jaroslav Kysela <perex@perex.cz>
Date: Sat, 12 Aug 2000 15:33:17 +0000
Subject: [PATCH] Cleanups and new control functions (hfirst, hlast, hnext,
 hprev, hcount).

---
 include/control.h      | 17 +++++++++++++++--
 src/control/controls.c | 38 ++++++++++++++++++++++++++++++++++++++
 2 files changed, 53 insertions(+), 2 deletions(-)

diff --git a/include/control.h b/include/control.h
index af1eba9b..ad88add7 100644
--- a/include/control.h
+++ b/include/control.h
@@ -50,6 +50,10 @@ int snd_ctl_rawmidi_info(snd_ctl_t *handle, snd_rawmidi_info_t * info);
 
 int snd_ctl_read(snd_ctl_t *handle, snd_ctl_callbacks_t * callbacks);
 
+#ifdef __cplusplus
+}
+#endif
+
 /*
  *  Highlevel API for controls
  */
@@ -86,12 +90,21 @@ struct snd_hcontrol_stru {
 	snd_ctl_t *handle;	/* associated handle */
 };
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 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);
+typedef void (snd_ctl_hcallback_rebuild_t)(snd_ctl_t *handle, void *private_data);
+typedef void (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_hfirst(snd_ctl_t *handle);
+snd_hcontrol_t *snd_ctl_hlast(snd_ctl_t *handle);
+snd_hcontrol_t *snd_ctl_hnext(snd_ctl_t *handle, snd_hcontrol_t *hcontrol);
+snd_hcontrol_t *snd_ctl_hprev(snd_ctl_t *handle, snd_hcontrol_t *hcontrol);
+int snd_ctl_hcount(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);
diff --git a/src/control/controls.c b/src/control/controls.c
index 9a169423..6d31968b 100644
--- a/src/control/controls.c
+++ b/src/control/controls.c
@@ -190,6 +190,44 @@ int snd_ctl_hresort(snd_ctl_t *handle, snd_ctl_hsort_t *hsort)
 	return 0;
 }
 
+snd_hcontrol_t *snd_ctl_hfirst(snd_ctl_t *handle)
+{
+	assert(handle != NULL);
+	if (list_empty(&handle->hlist))
+		return NULL;
+	return (snd_hcontrol_t *)list_entry(handle->hlist.next, snd_hcontrol_t, list);
+}
+
+snd_hcontrol_t *snd_ctl_hlast(snd_ctl_t *handle)
+{
+	assert(handle != NULL);
+	if (list_empty(&handle->hlist))
+		return NULL;
+	return (snd_hcontrol_t *)list_entry(handle->hlist.prev, snd_hcontrol_t, list);
+}
+
+snd_hcontrol_t *snd_ctl_hnext(snd_ctl_t *handle, snd_hcontrol_t *hcontrol)
+{
+	assert(handle != NULL && hcontrol != NULL);
+	if (hcontrol->list.next == &handle->hlist)
+		return NULL;
+	return (snd_hcontrol_t *)list_entry(hcontrol->list.next, snd_hcontrol_t, list);
+}
+
+snd_hcontrol_t *snd_ctl_hprev(snd_ctl_t *handle, snd_hcontrol_t *hcontrol)
+{
+	assert(handle != NULL && hcontrol != NULL);
+	if (hcontrol->list.prev == &handle->hlist)
+		return NULL;
+	return (snd_hcontrol_t *)list_entry(hcontrol->list.prev, snd_hcontrol_t, list);
+}
+
+int snd_ctl_hcount(snd_ctl_t *handle)
+{
+	assert(handle != NULL);
+	return handle->hcount;
+}
+
 snd_hcontrol_t *snd_ctl_hfind(snd_ctl_t *handle, snd_control_id_t *id)
 {
 	void *res;
-- 
2.47.1