/*
- * Copyright (C) 2005-2006 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2005-2009 Andre Noll <maan@systemlinux.org>
*
- * 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., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
+ * Licensed under the GPL v2. For licencing details see COPYING.
*/
/** \file alsa_write.c paraslash's alsa output plugin */
* based on the vplay program by Michael Beck.
*/
+#include <sys/types.h>
+#include <dirent.h>
+#include <alsa/asoundlib.h>
+
#include "para.h"
#include "fd.h"
#include "string.h"
#include "list.h"
#include "sched.h"
+#include "ggo.h"
#include "write.h"
-
-#include <alsa/asoundlib.h>
-
#include "alsa_write.cmdline.h"
#include "error.h"
-
+/** always use 16 bit little endian */
#define FORMAT SND_PCM_FORMAT_S16_LE
-/** data specific to the alsa writer */
+/** Data specific to the alsa writer. */
struct private_alsa_write_data {
- /** the alsa handle */
+ /** The alsa handle */
snd_pcm_t *handle;
- /** determined and set by alsa_open() */
- size_t bytes_per_frame;
- /** don't write anything until this time */
+ /** Determined and set by alsa_open(). */
+ int bytes_per_frame;
+ /** Don't write anything until this time. */
struct timeval next_chunk;
- /** the return value of snd_pcm_hw_params_get_buffer_time_max() */
+ /** The approximate maximum buffer duration in us. */
unsigned buffer_time;
+ /**
+ * The samplerate given by command line option or the decoder
+ * of the writer node group.
+ */
unsigned samplerate;
+ /**
+ * The number of channels, given by command line option or the
+ * decoder of the writer node group.
+ */
unsigned channels;
};
-/*
- * open and prepare the PCM handle for writing
- *
- * Install PCM software and hardware configuration. Exit on errors.
- */
-static int alsa_open(struct writer_node *w)
+/* Install PCM software and hardware configuration. */
+static int alsa_init(struct private_alsa_write_data *pad,
+ struct alsa_write_args_info *conf)
{
snd_pcm_hw_params_t *hwparams;
snd_pcm_sw_params_t *swparams;
- snd_pcm_uframes_t buffer_size, xfer_align, start_threshold,
- stop_threshold;
- int err;
- snd_pcm_info_t *info;
+ snd_pcm_uframes_t buffer_size, start_threshold, stop_threshold;
snd_pcm_uframes_t period_size;
- struct private_alsa_write_data *pad = para_calloc(sizeof(struct
- private_alsa_write_data));
- struct alsa_write_args_info *conf = w->conf;
- struct writer_node_group *wng = w->wng;
+ int err;
- if (!conf->samplerate_given && wng->samplerate)
- pad->samplerate = *wng->samplerate;
- else
- pad->samplerate = conf->samplerate_arg;
- if (!conf->channels_given && wng->channels)
- pad->channels = *wng->channels;
- else
- pad->channels = conf->channels_arg;
- PARA_INFO_LOG("%d channel(s), %dHz\n", pad->channels, pad->samplerate);
- w->private_data = pad;
- snd_pcm_info_alloca(&info);
err = snd_pcm_open(&pad->handle, conf->device_arg,
SND_PCM_STREAM_PLAYBACK, SND_PCM_NONBLOCK);
if (err < 0)
return -E_PCM_OPEN;
- if ((err = snd_pcm_info(pad->handle, info)) < 0)
- return -E_SND_PCM_INFO;
snd_pcm_hw_params_alloca(&hwparams);
snd_pcm_sw_params_alloca(&swparams);
if (period_size == buffer_size)
return -E_BAD_PERIOD;
snd_pcm_sw_params_current(pad->handle, swparams);
- err = snd_pcm_sw_params_get_xfer_align(swparams, &xfer_align);
- if (err < 0 || !xfer_align)
- return -E_GET_XFER;
snd_pcm_sw_params_set_avail_min(pad->handle, swparams, period_size);
- /* round to closest transfer boundary */
- start_threshold = (buffer_size / xfer_align) * xfer_align;
- if (start_threshold < 1)
+ if (buffer_size < 1)
start_threshold = 1;
+ else
+ start_threshold = PARA_MIN(buffer_size,
+ (snd_pcm_uframes_t)pad->samplerate);
if (snd_pcm_sw_params_set_start_threshold(pad->handle, swparams,
start_threshold) < 0)
return -E_START_THRESHOLD;
if (snd_pcm_sw_params_set_stop_threshold(pad->handle, swparams,
stop_threshold) < 0)
return -E_STOP_THRESHOLD;
- if (snd_pcm_sw_params_set_xfer_align(pad->handle, swparams,
- xfer_align) < 0)
- return -E_SET_XFER;
if (snd_pcm_sw_params(pad->handle, swparams) < 0)
- return -E_SW_PARAMS;
+ PARA_WARNING_LOG("unable to install sw params\n");
pad->bytes_per_frame = snd_pcm_format_physical_width(FORMAT)
* pad->channels / 8;
+ if (pad->bytes_per_frame <= 0)
+ return -E_PHYSICAL_WIDTH;
+ PARA_INFO_LOG("bytes per frame: %d\n", pad->bytes_per_frame);
if (snd_pcm_nonblock(pad->handle, 1))
- PARA_ERROR_LOG("%s\n", "failed to set nonblock mode");
- return period_size * pad->bytes_per_frame;
+ PARA_ERROR_LOG("failed to set nonblock mode\n");
+ return 1;
+}
+
+/* Open an instance of the alsa writer. */
+static int alsa_open(struct writer_node *wn)
+{
+ struct alsa_write_args_info *conf = wn->conf;
+ struct writer_node_group *wng = wn->wng;
+ struct private_alsa_write_data *pad = para_calloc(sizeof(*pad));
+
+ wn->private_data = pad;
+ if (!conf->samplerate_given && wng->samplerate)
+ pad->samplerate = *wng->samplerate;
+ else
+ pad->samplerate = conf->samplerate_arg;
+ if (!conf->channels_given && wng->channels)
+ pad->channels = *wng->channels;
+ else
+ pad->channels = conf->channels_arg;
+ PARA_INFO_LOG("%d channel(s), %dHz\n", pad->channels, pad->samplerate);
+ tv_add(now, &(struct timeval){0, 100 * 1000}, &pad->next_chunk);
+ return 1;
}
static int alsa_write_pre_select(struct sched *s, struct writer_node *wn)
struct writer_node_group *wng = wn->wng;
struct timeval diff;
- if (*wng->loaded < pad->bytes_per_frame)
+ if (!*wng->loaded)
return 1;
if (tv_diff(now, &pad->next_chunk, &diff) < 0) {
if (tv_diff(&s->timeout, &diff, NULL) > 0)
s->timeout.tv_usec = 1;
}
return 1;
-// PARA_INFO_LOG("timeout: %lu\n", tv2ms(&s->timeout));
}
static int alsa_write_post_select(__a_unused struct sched *s,
{
struct private_alsa_write_data *pad = wn->private_data;
struct writer_node_group *wng = wn->wng;
- size_t frames = (*wng->loaded - wn->written) / pad->bytes_per_frame;
- snd_pcm_sframes_t ret;
+ size_t frames, bytes = *wng->loaded - wn->written;
unsigned char *data = (unsigned char*)wng->buf + wn->written;
struct timeval tv;
+ snd_pcm_sframes_t ret;
-// PARA_INFO_LOG("%zd frames\n", frames);
- if (!frames) {
- if (*wng->input_eof)
- wn->written = *wng->loaded;
- return 1;
+ if (*wng->input_error < 0 && (!pad->handle || bytes < pad->bytes_per_frame)) {
+ wn->written = *wng->loaded;
+ return *wng->input_error;
}
+ if (!bytes) /* no data available */
+ goto out;
if (tv_diff(now, &pad->next_chunk, NULL) < 0)
- return 1;
+ goto out;
+ if (!pad->handle) {
+ int err = alsa_init(pad, wn->conf);
+ if (err < 0)
+ return err;
+ }
+ frames = bytes / pad->bytes_per_frame;
+ if (!frames) /* less than a single frame available */
+ goto out;
ret = snd_pcm_writei(pad->handle, data, frames);
if (ret == -EPIPE) {
- PARA_WARNING_LOG("%s", "EPIPE\n");
+ PARA_WARNING_LOG("EPIPE\n");
snd_pcm_prepare(pad->handle);
return 1;
}
- if (ret < 0) {
- PARA_WARNING_LOG("%s", "ALSA ERROR\n");
+ if (ret < 0 && ret != -EAGAIN) {
+ PARA_WARNING_LOG("alsa error (%zu frames, ret = %d\n",
+ frames, (int)ret);
return -E_ALSA_WRITE;
}
- ms2tv(pad->buffer_time / 4000, &tv);
-// ms2tv(1, &tv);
- tv_add(now, &tv, &pad->next_chunk);
- wn->written += ret * pad->bytes_per_frame;
+ if (ret == -EAGAIN)
+ PARA_DEBUG_LOG("EAGAIN\n");
+ else
+ wn->written += ret * pad->bytes_per_frame;
+ if (ret == frames) /* we wrote everything, try again immediately */
+ pad->next_chunk = *now;
+ else { /* wait until 50% buffer space is available */
+ ms2tv(pad->buffer_time / 2000, &tv);
+ tv_add(now, &tv, &pad->next_chunk);
+ }
+out:
return 1;
}
{
struct private_alsa_write_data *pad = wn->private_data;
PARA_INFO_LOG("closing writer node %p\n", wn);
- snd_pcm_drain(pad->handle);
- snd_pcm_close(pad->handle);
- snd_config_update_free_global();
+
+ if (pad->handle) {
+ snd_pcm_drain(pad->handle);
+ snd_pcm_close(pad->handle);
+ snd_config_update_free_global();
+ }
free(pad);
}
__malloc static void *alsa_parse_config(const char *options)
{
+ int ret;
struct alsa_write_args_info *conf
= para_calloc(sizeof(struct alsa_write_args_info));
- PARA_INFO_LOG("options: %s, %d\n", options, strcspn(options, " \t"));
- int ret = alsa_cmdline_parser_string(options, conf, "alsa_write");
+
+ PARA_INFO_LOG("options: %s, %zd\n", options, strcspn(options, " \t"));
+ ret = alsa_cmdline_parser_string(options, conf, "alsa_write");
if (ret)
goto err_out;
PARA_INFO_LOG("help given: %d\n", conf->help_given);
return NULL;
}
-/** the init function of the alsa writer */
+/**
+ * the init function of the alsa writer
+ *
+ * \param w pointer to the writer to initialize
+ *
+ * \sa struct writer
+ */
void alsa_write_init(struct writer *w)
{
+ struct alsa_write_args_info dummy;
+
+ alsa_cmdline_parser_init(&dummy);
w->open = alsa_open;
w->close = alsa_close;
w->pre_select = alsa_write_pre_select;
w->post_select = alsa_write_post_select;
w->parse_config = alsa_parse_config;
w->shutdown = NULL; /* nothing to do */
+ w->help = (struct ggo_help) {
+ .short_help = alsa_write_args_info_help,
+ .detailed_help = alsa_write_args_info_detailed_help
+ };
}
projects / paraslash.git / blobdiff