ardour/libs/ardouralsautil/devicelist.cc

/*
 * Copyright (C) 2014 Robin Gareus <robin@gareus.org>
 * Copyright (C) 2013 Paul Davis
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <alsa/asoundlib.h>
#include "pbd/convert.h"
#include "ardouralsautil/devicelist.h"

using namespace std;

void
ARDOUR::get_alsa_audio_device_names (std::map<std::string, std::string>& devices)
{
	snd_ctl_t *handle;
	snd_ctl_card_info_t *info;
	snd_pcm_info_t *pcminfo;
	snd_ctl_card_info_alloca(&info);
	snd_pcm_info_alloca(&pcminfo);
	string devname;
	int cardnum = -1;
	int device = -1;

	while (snd_card_next (&cardnum) >= 0 && cardnum >= 0) {

		devname = "hw:";
		devname += PBD::to_string (cardnum, std::dec);

		if (snd_ctl_open (&handle, devname.c_str(), 0) >= 0 && snd_ctl_card_info (handle, info) >= 0) {

			if (snd_ctl_card_info (handle, info) < 0) {
				continue;
			}

			string card_name = snd_ctl_card_info_get_name (info);

			/* change devname to use ID, not number */

			devname = "hw:";
			devname += snd_ctl_card_info_get_id (info);

			while (snd_ctl_pcm_next_device (handle, &device) >= 0 && device >= 0) {

				/* only detect duplex devices here. more
				 * complex arrangements are beyond our scope
				 */

				snd_pcm_info_set_device (pcminfo, device);
				snd_pcm_info_set_subdevice (pcminfo, 0);
				snd_pcm_info_set_stream (pcminfo, SND_PCM_STREAM_CAPTURE);

				if (snd_ctl_pcm_info (handle, pcminfo) < 0) {
					continue;
				}

				snd_pcm_info_set_device (pcminfo, device);
				snd_pcm_info_set_subdevice (pcminfo, 0);
				snd_pcm_info_set_stream (pcminfo, SND_PCM_STREAM_PLAYBACK);

				if (snd_ctl_pcm_info (handle, pcminfo) < 0) {
					continue;
				}
				devname += ',';
				devname += PBD::to_string (device, std::dec);
				devices.insert (std::make_pair (card_name, devname));
			}

			snd_ctl_close(handle);
		}
	}
}

void
ARDOUR::get_alsa_rawmidi_device_names (std::map<std::string, std::string>& devices)
{
	int cardnum = -1;
	snd_ctl_card_info_t *cinfo;
	snd_ctl_card_info_alloca (&cinfo);
	while (snd_card_next (&cardnum) >= 0 && cardnum >= 0) {
		snd_ctl_t *handle;
		std::string devname = "hw:";
		devname += PBD::to_string (cardnum, std::dec);
		if (snd_ctl_open (&handle, devname.c_str (), 0) >= 0 && snd_ctl_card_info (handle, cinfo) >= 0) {
			int device = -1;
			while (snd_ctl_rawmidi_next_device (handle, &device) >= 0 && device >= 0) {
				snd_rawmidi_info_t *info;
				snd_rawmidi_info_alloca (&info);
				snd_rawmidi_info_set_device (info, device);

				int subs_in, subs_out;

				snd_rawmidi_info_set_stream (info, SND_RAWMIDI_STREAM_INPUT);
				if (snd_ctl_rawmidi_info (handle, info) >= 0) {
					subs_in = snd_rawmidi_info_get_subdevices_count (info);
				} else {
					subs_in = 0;
				}

				snd_rawmidi_info_set_stream (info, SND_RAWMIDI_STREAM_OUTPUT);
				if (snd_ctl_rawmidi_info (handle, info) >= 0) {
					subs_out = snd_rawmidi_info_get_subdevices_count (info);
				} else {
					subs_out = 0;
				}

				const int subs = subs_in > subs_out ? subs_in : subs_out;
				if (!subs) {
					continue;
				}

				for (int sub = 0; sub < subs; ++sub) {
					snd_rawmidi_info_set_stream (info, sub < subs_in ?
							SND_RAWMIDI_STREAM_INPUT :
							SND_RAWMIDI_STREAM_OUTPUT);

					snd_rawmidi_info_set_subdevice (info, sub);
					if (snd_ctl_rawmidi_info (handle, info) < 0) {
						continue;
					}

					const char *sub_name = snd_rawmidi_info_get_subdevice_name (info);
					if (sub == 0 && sub_name[0] == '\0') {
						devname = "hw:";
						devname += snd_ctl_card_info_get_id (cinfo);
						devname += ",";
						devname += PBD::to_string (device, std::dec);

						std::string card_name;
						card_name = snd_rawmidi_info_get_name (info);
						card_name += " (";
						if (sub < subs_in) card_name += "I";
						if (sub < subs_out) card_name += "O";
						card_name += ")";

						devices.insert (std::make_pair (card_name, devname));
						break;
					} else {
						devname = "hw:";
						devname += snd_ctl_card_info_get_id (cinfo);
						devname += ",";
						devname += PBD::to_string (device, std::dec);
						devname += ",";
						devname += PBD::to_string (sub, std::dec);

						std::string card_name = sub_name;
						card_name += " (";
						if (sub < subs_in) card_name += "I";
						if (sub < subs_out) card_name += "O";
						card_name += ")";
						devices.insert (std::make_pair (card_name, devname));
					}
				}
			}
			snd_ctl_close (handle);
		}
	}
}

int
ARDOUR::card_to_num(const char* device_name)
{
	char* ctl_name;
	const char * comma;
	snd_ctl_t* ctl_handle;
	int i = -1;

	if (strncasecmp(device_name, "plughw:", 7) == 0) {
		device_name += 4;
	}
	if (!(comma = strchr(device_name, ','))) {
		ctl_name = strdup(device_name);
	} else {
		ctl_name = strndup(device_name, comma - device_name);
	}

	if (snd_ctl_open (&ctl_handle, ctl_name, 0) >= 0) {
		snd_ctl_card_info_t *card_info;
		snd_ctl_card_info_alloca (&card_info);
		if (snd_ctl_card_info(ctl_handle, card_info) >= 0) {
			i = snd_ctl_card_info_get_card(card_info);
		}
		snd_ctl_close(ctl_handle);
	}
	free(ctl_name);
	return i;
}