libao2: change control() types to enum, remove unused ones

Change the audio driver control() command argument from "int" to "enum
aocontrol". Remove unused control types (SET_DEVICE, GET_DEVICE,
QUERY_FORMAT, SET_PLUGIN_DRIVER, SET_PLUGIN_LIST). The QUERY_FORMAT
one looks like there's a possibility such functionality could be
useful in the future, but as ao_oss was the only driver to have an
actual implementation of it, the current code wasn't worth keeping.

libao2/ao_alsa.c

@@ -97,8 +97,6 @@ static void alsa_error_handler(const char *file, int line, const char *function,
 static int control(int cmd, void *arg)
 {
   switch(cmd) {
-  case AOCONTROL_QUERY_FORMAT:
-    return CONTROL_TRUE;
   case AOCONTROL_GET_VOLUME:
   case AOCONTROL_SET_VOLUME:
     {

libao2/ao_oss.c

@@ -179,22 +179,6 @@ static int volume_oss4(ao_control_vol_t *vol, int cmd) {
 // to set/get/query special features/parameters
 static int control(int cmd,void *arg){
     switch(cmd){
-	case AOCONTROL_SET_DEVICE:
-	    dsp=(char*)arg;
-	    return CONTROL_OK;
-	case AOCONTROL_GET_DEVICE:
-	    *(char**)arg=dsp;
-	    return CONTROL_OK;
-#ifdef SNDCTL_DSP_GETFMTS
-	case AOCONTROL_QUERY_FORMAT:
-	{
-	    int format;
-	    if (!ioctl(audio_fd, SNDCTL_DSP_GETFMTS, &format))
-		if ((unsigned int)format & (unsigned long)arg)
-	    	    return CONTROL_TRUE;
-	    return CONTROL_FALSE;
-	}
-#endif
 	case AOCONTROL_GET_VOLUME:
 	case AOCONTROL_SET_VOLUME:
 	{

libao2/ao_pulse.c

@@ -420,7 +420,7 @@ static void info_func(struct pa_context *c, const struct pa_sink_input_info *i,
     pa_threaded_mainloop_signal(priv->mainloop, 0);
 }
 
-static int control(struct ao *ao, int cmd, void *arg)
+static int control(struct ao *ao, enum aocontrol cmd, void *arg)
 {
     struct priv *priv = ao->priv;
     switch (cmd) {

libao2/ao_sgi.c

@@ -118,13 +118,6 @@ static int control(int cmd, void *arg){
 
   mp_tmsg(MSGT_AO, MSGL_INFO, "[AO SGI] control.\n");
 
-  switch(cmd) {
-  case AOCONTROL_QUERY_FORMAT:
-    /* Do not reject any format: return the closest matching
-     * format if the request is not supported natively. */
-    return CONTROL_TRUE;
-  }
-
   return CONTROL_UNKNOWN;
 }
 

libao2/ao_sun.c

@@ -402,11 +402,6 @@ static void setup_device_paths(void)
 // to set/get/query special features/parameters
 static int control(int cmd,void *arg){
     switch(cmd){
-    case AOCONTROL_SET_DEVICE:
-	audio_dev=(char*)arg;
-	return CONTROL_OK;
-    case AOCONTROL_QUERY_FORMAT:
-	return CONTROL_TRUE;
     case AOCONTROL_GET_VOLUME:
     {
         int fd;

libao2/audio_out.c

@@ -232,7 +232,7 @@ int ao_play(struct ao *ao, void *data, int len, int flags)
     return ao->driver->play(ao, data, len, flags);
 }
 
-int ao_control(struct ao *ao, int cmd, void *arg)
+int ao_control(struct ao *ao, enum aocontrol cmd, void *arg)
 {
     if (ao->driver->control)
         return ao->driver->control(ao, cmd, arg);
@@ -299,7 +299,7 @@ int old_ao_play(struct ao *ao, void *data, int len, int flags)
     return ao->driver->old_functions->play(data, len, flags);
 }
 
-int old_ao_control(struct ao *ao, int cmd, void *arg)
+int old_ao_control(struct ao *ao, enum aocontrol cmd, void *arg)
 {
     return ao->driver->old_functions->control(cmd, arg);
 }

libao2/audio_out.h

@@ -23,6 +23,27 @@
 
 #include "bstr.h"
 
+#define CONTROL_OK 1
+#define CONTROL_TRUE 1
+#define CONTROL_FALSE 0
+#define CONTROL_UNKNOWN -1
+#define CONTROL_ERROR -2
+#define CONTROL_NA -3
+
+enum aocontrol {
+    // _VOLUME commands take struct ao_control_vol pointer for input/output.
+    // If there's only one volume, SET should use average of left/right.
+    AOCONTROL_GET_VOLUME,
+    AOCONTROL_SET_VOLUME,
+};
+
+#define AOPLAY_FINAL_CHUNK 1
+
+typedef struct ao_control_vol {
+    float left;
+    float right;
+} ao_control_vol_t;
+
 typedef struct ao_info {
     /* driver name ("Matrox Millennium G200/G400" */
     const char *name;
@@ -53,7 +74,7 @@ struct ao_driver {
     bool is_new;
     const struct ao_info *info;
     const struct ao_old_functions *old_functions;
-    int (*control)(struct ao *ao, int cmd, void *arg);
+    int (*control)(struct ao *ao, enum aocontrol cmd, void *arg);
     int (*init)(struct ao *ao, char *params);
     void (*uninit)(struct ao *ao, bool cut_audio);
     void (*reset)(struct ao*ao);
@@ -88,40 +109,18 @@ extern char *ao_subdevice;
 
 void list_audio_out(void);
 
-#define CONTROL_OK 1
-#define CONTROL_TRUE 1
-#define CONTROL_FALSE 0
-#define CONTROL_UNKNOWN -1
-#define CONTROL_ERROR -2
-#define CONTROL_NA -3
-
-#define AOCONTROL_SET_DEVICE 1
-#define AOCONTROL_GET_DEVICE 2
-#define AOCONTROL_QUERY_FORMAT 3 /* test for availabilty of a format */
-#define AOCONTROL_GET_VOLUME 4
-#define AOCONTROL_SET_VOLUME 5
-#define AOCONTROL_SET_PLUGIN_DRIVER 6
-#define AOCONTROL_SET_PLUGIN_LIST 7
-
-#define AOPLAY_FINAL_CHUNK 1
-
-typedef struct ao_control_vol {
-    float left;
-    float right;
-} ao_control_vol_t;
-
 struct ao *ao_create(struct MPOpts *opts, struct input_ctx *input);
 void ao_init(struct ao *ao, char **ao_list);
 void ao_uninit(struct ao *ao, bool cut_audio);
 int ao_play(struct ao *ao, void *data, int len, int flags);
-int ao_control(struct ao *ao, int cmd, void *arg);
+int ao_control(struct ao *ao, enum aocontrol cmd, void *arg);
 double ao_get_delay(struct ao *ao);
 int ao_get_space(struct ao *ao);
 void ao_reset(struct ao *ao);
 void ao_pause(struct ao *ao);
 void ao_resume(struct ao *ao);
 
-int old_ao_control(struct ao *ao, int cmd, void *arg);
+int old_ao_control(struct ao *ao, enum aocontrol cmd, void *arg);
 int old_ao_init(struct ao *ao, char *params);
 void old_ao_uninit(struct ao *ao, bool cut_audio);
 void old_ao_reset(struct ao*ao);