FreeRDP/channels/rdpsnd/client/alsa/rdpsnd_alsa.c
2012-10-08 23:02:04 -04:00

460 lines
11 KiB
C

/**
* FreeRDP: A Remote Desktop Protocol Implementation
* Audio Output Virtual Channel
*
* Copyright 2009-2011 Jay Sorg
* Copyright 2010-2011 Vic Lee
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <alsa/asoundlib.h>
#include <freerdp/types.h>
#include <freerdp/utils/memory.h>
#include <freerdp/utils/dsp.h>
#include <freerdp/utils/svc_plugin.h>
#include "rdpsnd_main.h"
typedef struct rdpsnd_alsa_plugin rdpsndAlsaPlugin;
struct rdpsnd_alsa_plugin
{
rdpsndDevicePlugin device;
char* device_name;
snd_pcm_t* out_handle;
snd_mixer_t* mixer_handle;
uint32 source_rate;
uint32 actual_rate;
snd_pcm_format_t format;
uint32 source_channels;
uint32 actual_channels;
int bytes_per_channel;
int wformat;
int block_size;
int latency;
FREERDP_DSP_CONTEXT* dsp_context;
};
static void rdpsnd_alsa_set_params(rdpsndAlsaPlugin* alsa)
{
int status;
snd_pcm_hw_params_t* hw_params;
snd_pcm_sw_params_t* sw_params;
snd_pcm_uframes_t frames;
snd_pcm_uframes_t start_threshold;
snd_pcm_drop(alsa->out_handle);
status = snd_pcm_hw_params_malloc(&hw_params);
if (status < 0)
{
DEBUG_WARN("snd_pcm_hw_params_malloc failed");
return;
}
snd_pcm_hw_params_any(alsa->out_handle, hw_params);
snd_pcm_hw_params_set_access(alsa->out_handle, hw_params, SND_PCM_ACCESS_RW_INTERLEAVED);
snd_pcm_hw_params_set_format(alsa->out_handle, hw_params, alsa->format);
snd_pcm_hw_params_set_rate_near(alsa->out_handle, hw_params, &alsa->actual_rate, NULL);
snd_pcm_hw_params_set_channels_near(alsa->out_handle, hw_params, &alsa->actual_channels);
if (alsa->latency < 0)
frames = alsa->actual_rate * 4 / 10; /* Default to 400ms buffer */
else
frames = alsa->latency * alsa->actual_rate * 2 / 1000; /* Double of the latency */
if (frames < alsa->actual_rate / 2)
frames = alsa->actual_rate / 2; /* Minimum 0.5-second buffer */
snd_pcm_hw_params_set_buffer_size_near(alsa->out_handle, hw_params, &frames);
snd_pcm_hw_params(alsa->out_handle, hw_params);
snd_pcm_hw_params_free(hw_params);
status = snd_pcm_sw_params_malloc(&sw_params);
if (status < 0)
{
DEBUG_WARN("snd_pcm_sw_params_malloc failed");
return;
}
snd_pcm_sw_params_current(alsa->out_handle, sw_params);
if (alsa->latency == 0)
start_threshold = 0;
else
start_threshold = frames / 2;
snd_pcm_sw_params_set_start_threshold(alsa->out_handle, sw_params, start_threshold);
snd_pcm_sw_params(alsa->out_handle, sw_params);
snd_pcm_sw_params_free(sw_params);
snd_pcm_prepare(alsa->out_handle);
DEBUG_SVC("hardware buffer %d frames, playback buffer %.2g seconds",
(int) frames, (double) frames / 2.0 / (double) alsa->actual_rate);
if ((alsa->actual_rate != alsa->source_rate) || (alsa->actual_channels != alsa->source_channels))
{
DEBUG_SVC("actual rate %d / channel %d is different from source rate %d / channel %d, resampling required.",
alsa->actual_rate, alsa->actual_channels, alsa->source_rate, alsa->source_channels);
}
}
static void rdpsnd_alsa_set_format(rdpsndDevicePlugin* device, rdpsndFormat* format, int latency)
{
rdpsndAlsaPlugin* alsa = (rdpsndAlsaPlugin*)device;
if (format != NULL)
{
alsa->source_rate = format->nSamplesPerSec;
alsa->actual_rate = format->nSamplesPerSec;
alsa->source_channels = format->nChannels;
alsa->actual_channels = format->nChannels;
switch (format->wFormatTag)
{
case 1: /* PCM */
switch (format->wBitsPerSample)
{
case 8:
alsa->format = SND_PCM_FORMAT_S8;
alsa->bytes_per_channel = 1;
break;
case 16:
alsa->format = SND_PCM_FORMAT_S16_LE;
alsa->bytes_per_channel = 2;
break;
}
break;
case 2: /* MS ADPCM */
case 0x11: /* IMA ADPCM */
alsa->format = SND_PCM_FORMAT_S16_LE;
alsa->bytes_per_channel = 2;
break;
}
alsa->wformat = format->wFormatTag;
alsa->block_size = format->nBlockAlign;
}
alsa->latency = latency;
rdpsnd_alsa_set_params(alsa);
}
static void rdpsnd_alsa_open_mixer(rdpsndAlsaPlugin* alsa)
{
int status;
snd_mixer_t* handle;
status = snd_mixer_open(&handle, 0);
if (status < 0)
{
DEBUG_WARN("snd_mixer_open failed");
return;
}
status = snd_mixer_attach(handle, alsa->device_name);
if (status < 0)
{
DEBUG_WARN("snd_mixer_attach failed");
snd_mixer_close(handle);
return;
}
status = snd_mixer_selem_register(handle, NULL, NULL);
if (status < 0)
{
DEBUG_WARN("snd_mixer_selem_register failed");
snd_mixer_close(handle);
return;
}
status = snd_mixer_load(handle);
if (status < 0)
{
DEBUG_WARN("snd_mixer_load failed");
snd_mixer_close(handle);
return;
}
alsa->mixer_handle = handle;
}
static void rdpsnd_alsa_open(rdpsndDevicePlugin* device, rdpsndFormat* format, int latency)
{
int status;
rdpsndAlsaPlugin* alsa = (rdpsndAlsaPlugin*) device;
if (alsa->out_handle != 0)
return;
DEBUG_SVC("opening");
status = snd_pcm_open(&alsa->out_handle, alsa->device_name, SND_PCM_STREAM_PLAYBACK, 0);
if (status < 0)
{
DEBUG_WARN("snd_pcm_open failed");
}
else
{
freerdp_dsp_context_reset_adpcm(alsa->dsp_context);
rdpsnd_alsa_set_format(device, format, latency);
rdpsnd_alsa_open_mixer(alsa);
}
}
static void rdpsnd_alsa_close(rdpsndDevicePlugin* device)
{
rdpsndAlsaPlugin* alsa = (rdpsndAlsaPlugin*)device;
if (alsa->out_handle != 0)
{
DEBUG_SVC("close");
snd_pcm_drain(alsa->out_handle);
snd_pcm_close(alsa->out_handle);
alsa->out_handle = 0;
}
if (alsa->mixer_handle)
{
snd_mixer_close(alsa->mixer_handle);
alsa->mixer_handle = NULL;
}
}
static void rdpsnd_alsa_free(rdpsndDevicePlugin* device)
{
rdpsndAlsaPlugin* alsa = (rdpsndAlsaPlugin*)device;
rdpsnd_alsa_close(device);
xfree(alsa->device_name);
freerdp_dsp_context_free(alsa->dsp_context);
xfree(alsa);
}
static boolean rdpsnd_alsa_format_supported(rdpsndDevicePlugin* device, rdpsndFormat* format)
{
switch (format->wFormatTag)
{
case 1: /* PCM */
if (format->cbSize == 0 &&
format->nSamplesPerSec <= 48000 &&
(format->wBitsPerSample == 8 || format->wBitsPerSample == 16) &&
(format->nChannels == 1 || format->nChannels == 2))
{
return true;
}
break;
case 2: /* MS ADPCM */
case 0x11: /* IMA ADPCM */
if (format->nSamplesPerSec <= 48000 &&
format->wBitsPerSample == 4 &&
(format->nChannels == 1 || format->nChannels == 2))
{
return true;
}
break;
}
return false;
}
static void rdpsnd_alsa_set_volume(rdpsndDevicePlugin* device, uint32 value)
{
long left;
long right;
long volume_min;
long volume_max;
long volume_left;
long volume_right;
snd_mixer_elem_t* elem;
rdpsndAlsaPlugin* alsa = (rdpsndAlsaPlugin*) device;
if (!alsa->mixer_handle)
return;
left = (value & 0xFFFF);
right = ((value >> 16) & 0xFFFF);
for (elem = snd_mixer_first_elem(alsa->mixer_handle); elem; elem = snd_mixer_elem_next(elem))
{
if (snd_mixer_selem_has_playback_volume(elem))
{
snd_mixer_selem_get_playback_volume_range(elem, &volume_min, &volume_max);
volume_left = volume_min + (left * (volume_max - volume_min)) / 0xFFFF;
volume_right = volume_min + (right * (volume_max - volume_min)) / 0xFFFF;
snd_mixer_selem_set_playback_volume(elem, SND_MIXER_SCHN_FRONT_LEFT, volume_left);
snd_mixer_selem_set_playback_volume(elem, SND_MIXER_SCHN_FRONT_RIGHT, volume_right);
}
}
}
static void rdpsnd_alsa_play(rdpsndDevicePlugin* device, uint8* data, int size)
{
uint8* src;
int len;
int status;
int frames;
int rbytes_per_frame;
int sbytes_per_frame;
uint8* pindex;
uint8* end;
rdpsndAlsaPlugin* alsa = (rdpsndAlsaPlugin*) device;
if (alsa->out_handle == 0)
return;
if (alsa->wformat == 2)
{
alsa->dsp_context->decode_ms_adpcm(alsa->dsp_context,
data, size, alsa->source_channels, alsa->block_size);
size = alsa->dsp_context->adpcm_size;
src = alsa->dsp_context->adpcm_buffer;
}
else if (alsa->wformat == 0x11)
{
alsa->dsp_context->decode_ima_adpcm(alsa->dsp_context,
data, size, alsa->source_channels, alsa->block_size);
size = alsa->dsp_context->adpcm_size;
src = alsa->dsp_context->adpcm_buffer;
}
else
{
src = data;
}
sbytes_per_frame = alsa->source_channels * alsa->bytes_per_channel;
rbytes_per_frame = alsa->actual_channels * alsa->bytes_per_channel;
if ((size % sbytes_per_frame) != 0)
{
DEBUG_WARN("error len mod");
return;
}
if ((alsa->source_rate == alsa->actual_rate) && (alsa->source_channels == alsa->actual_channels))
{
}
else
{
alsa->dsp_context->resample(alsa->dsp_context, src, alsa->bytes_per_channel,
alsa->source_channels, alsa->source_rate, size / sbytes_per_frame,
alsa->actual_channels, alsa->actual_rate);
frames = alsa->dsp_context->resampled_frames;
DEBUG_SVC("resampled %d frames at %d to %d frames at %d",
size / sbytes_per_frame, alsa->source_rate, frames, alsa->actual_rate);
size = frames * rbytes_per_frame;
src = alsa->dsp_context->resampled_buffer;
}
pindex = src;
end = pindex + size;
while (pindex < end)
{
len = end - pindex;
frames = len / rbytes_per_frame;
status = snd_pcm_writei(alsa->out_handle, pindex, frames);
if (status == -EPIPE)
{
snd_pcm_recover(alsa->out_handle, status, 0);
status = 0;
}
else if (status < 0)
{
DEBUG_WARN("status %d", status);
snd_pcm_close(alsa->out_handle);
alsa->out_handle = 0;
rdpsnd_alsa_open(device, NULL, alsa->latency);
break;
}
pindex += status * rbytes_per_frame;
}
}
static void rdpsnd_alsa_start(rdpsndDevicePlugin* device)
{
rdpsndAlsaPlugin* alsa = (rdpsndAlsaPlugin*) device;
if (alsa->out_handle == 0)
return;
snd_pcm_start(alsa->out_handle);
}
int FreeRDPRdpsndDeviceEntry(PFREERDP_RDPSND_DEVICE_ENTRY_POINTS pEntryPoints)
{
rdpsndAlsaPlugin* alsa;
RDP_PLUGIN_DATA* data;
alsa = xnew(rdpsndAlsaPlugin);
alsa->device.Open = rdpsnd_alsa_open;
alsa->device.FormatSupported = rdpsnd_alsa_format_supported;
alsa->device.SetFormat = rdpsnd_alsa_set_format;
alsa->device.SetVolume = rdpsnd_alsa_set_volume;
alsa->device.Play = rdpsnd_alsa_play;
alsa->device.Start = rdpsnd_alsa_start;
alsa->device.Close = rdpsnd_alsa_close;
alsa->device.Free = rdpsnd_alsa_free;
data = pEntryPoints->plugin_data;
if (data && strcmp((char*) data->data[0], "alsa") == 0)
{
alsa->device_name = xstrdup((char*) data->data[1]);
}
if (alsa->device_name == NULL)
{
alsa->device_name = xstrdup("default");
}
alsa->out_handle = 0;
alsa->source_rate = 22050;
alsa->actual_rate = 22050;
alsa->format = SND_PCM_FORMAT_S16_LE;
alsa->source_channels = 2;
alsa->actual_channels = 2;
alsa->bytes_per_channel = 2;
alsa->dsp_context = freerdp_dsp_context_new();
pEntryPoints->pRegisterRdpsndDevice(pEntryPoints->rdpsnd, (rdpsndDevicePlugin*) alsa);
return 0;
}