/* -*- c-basic-offset: 8 -*-

rdesktop: A Remote Desktop Protocol client.

Sound Channel Process Functions - libao-driver

Copyright (C) Matthew Chapman <matthewc.unsw.edu.au> 2003-2008

Copyright (C) GuoJunBo <guojunbo@ict.ac.cn> 2003

Copyright (C) Michael Gernoth <mike@zerfleddert.de> 2005-2008

Copyright (C) 2013 Henrik Andersson

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 3 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, see <http://www.gnu.org/licenses/>.

*/

#include "rdesktop.h"

#include "rdpsnd.h"

#include "rdpsnd_dsp.h"

#include <unistd.h>

#include <fcntl.h>

#include <errno.h>

#include <ao/ao.h>

#include <sys/time.h>

#define WAVEOUTLEN 16

static ao_device *o_device = NULL;

static int default_driver;

static RD_BOOL reopened;

static char *libao_device = NULL;

void libao_play(void);

void

libao_add_fds(int *n, fd_set * rfds, fd_set * wfds, struct timeval *tv)

{

/* We need to be called rather often... */

if (o_device != NULL && !rdpsnd_queue_empty())

FD_SET(0, wfds);

}

void

libao_check_fds(fd_set * rfds, fd_set * wfds)

{

if (o_device == NULL)

return;

if (!rdpsnd_queue_empty())

libao_play();

}

RD_BOOL

libao_open(void)

{

ao_sample_format format;

ao_initialize();

if (libao_device)

{

default_driver = ao_driver_id(libao_device);

}

else

{

default_driver = ao_default_driver_id();

}

memset(&format, 0, sizeof(format));

format.bits = 16;

format.channels = 2;

format.rate = 44100;

format.byte_format = AO_FMT_NATIVE;

o_device = ao_open_live(default_driver, &format, NULL);

if (o_device == NULL)

{

return False;

}

reopened = True;

return True;

}

void

libao_close(void)

{

/* Ack all remaining packets */

while (!rdpsnd_queue_empty())

{

rdpsnd_queue_next(0);

}

if (o_device != NULL)

ao_close(o_device);

o_device = NULL;

ao_shutdown();

}

RD_BOOL

libao_set_format(RD_WAVEFORMATEX * pwfx)

{

ao_sample_format format;

memset(&format, 0, sizeof(format));

format.bits = pwfx->wBitsPerSample;

format.channels = pwfx->nChannels;

format.rate = 44100;

format.byte_format = AO_FMT_NATIVE;

if (o_device != NULL)

ao_close(o_device);

o_device = ao_open_live(default_driver, &format, NULL);

if (o_device == NULL)

{

return False;

}

if (rdpsnd_dsp_resample_set(44100, pwfx->wBitsPerSample, pwfx->nChannels) == False)

{

return False;

}

reopened = True;

return True;

}

void

libao_play(void)

{

struct audio_packet *packet;

STREAM out;

int len;

static long prev_s, prev_us;

unsigned int duration;

struct timeval tv;

int next_tick;

if (reopened)

{

reopened = False;

gettimeofday(&tv, NULL);

prev_s = tv.tv_sec;

prev_us = tv.tv_usec;

}

/* We shouldn't be called if the queue is empty, but still */

if (rdpsnd_queue_empty())

return;

packet = rdpsnd_queue_current_packet();

out = &packet->s;

next_tick = rdpsnd_queue_next_tick();

len = (WAVEOUTLEN > (out->end - out->p)) ? (out->end - out->p) : WAVEOUTLEN;

ao_play(o_device, (char *) out->p, len);

out->p += len;

gettimeofday(&tv, NULL);

duration = ((tv.tv_sec - prev_s) * 1000000 + (tv.tv_usec - prev_us)) / 1000;

if (packet->tick > next_tick)

next_tick += 65536;

if ((out->p == out->end) || duration > next_tick - packet->tick + 500)

{

unsigned int delay_us;

prev_s = tv.tv_sec;

prev_us = tv.tv_usec;

if (abs((next_tick - packet->tick) - duration) > 20)

{

DEBUG(("duration: %d, calc: %d, ", duration, next_tick - packet->tick));

DEBUG(("last: %d, is: %d, should: %d\n", packet->tick,

(packet->tick + duration) % 65536, next_tick % 65536));

}

delay_us = ((out->size / 4) * (1000000 / 44100));

rdpsnd_queue_next(delay_us);

}

}

struct audio_driver *

libao_register(char *options)

{

static struct audio_driver libao_driver;

memset(&libao_driver, 0, sizeof(libao_driver));

libao_driver.name = "libao";

libao_driver.description = "libao output driver, default device: system dependent";

libao_driver.add_fds = libao_add_fds;

libao_driver.check_fds = libao_check_fds;

libao_driver.wave_out_open = libao_open;

libao_driver.wave_out_close = libao_close;

libao_driver.wave_out_format_supported = rdpsnd_dsp_resample_supported;

libao_driver.wave_out_set_format = libao_set_format;

libao_driver.wave_out_volume = rdpsnd_dsp_softvol_set;

libao_driver.need_byteswap_on_be = 1;

libao_driver.need_resampling = 1;

if (options)

{

libao_device = xstrdup(options);

}

return &libao_driver;

}