--- /dev/null
+/*
+ * Copyright (C) 2005-2006 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.
+ */
+
+/** \file alsa_write.c paraslash's alsa output plugin */
+
+/*
+ * Based in parts on aplay.c from the alsa-utils-1.0.8 package,
+ * Copyright (c) by Jaroslav Kysela <perex@suse.cz>, which is
+ * based on the vplay program by Michael Beck.
+ */
+
+#include "para.h"
+#include "fd.h"
+#include "string.h"
+#include "list.h"
+#include "sched.h"
+#include "write.h"
+
+#include <alsa/asoundlib.h>
+
+#include "alsa_write.cmdline.h"
+#include "error.h"
+
+
+#define FORMAT SND_PCM_FORMAT_S16_LE
+
+/** data specific to the alsa writer */
+struct private_alsa_write_data {
+ /** 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 */
+ struct timeval next_chunk;
+ /** the return value of snd_pcm_hw_params_get_buffer_time_max() */
+ unsigned buffer_time;
+ unsigned samplerate;
+ 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)
+{
+ 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 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;
+
+ 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 (snd_pcm_hw_params_any(pad->handle, hwparams) < 0)
+ return -E_BROKEN_CONF;
+ if (snd_pcm_hw_params_set_access(pad->handle, hwparams,
+ SND_PCM_ACCESS_RW_INTERLEAVED) < 0)
+ return -E_ACCESS_TYPE;
+ if (snd_pcm_hw_params_set_format(pad->handle, hwparams, FORMAT) < 0)
+ return -E_SAMPLE_FORMAT;
+ if (snd_pcm_hw_params_set_channels(pad->handle, hwparams,
+ pad->channels) < 0)
+ return -E_CHANNEL_COUNT;
+ if (snd_pcm_hw_params_set_rate_near(pad->handle, hwparams,
+ &pad->samplerate, 0) < 0)
+ return -E_SET_RATE;
+ err = snd_pcm_hw_params_get_buffer_time_max(hwparams, &pad->buffer_time, 0);
+ if (err < 0 || !pad->buffer_time)
+ return -E_GET_BUFFER_TIME;
+ PARA_INFO_LOG("buffer time: %d\n", pad->buffer_time);
+ if (snd_pcm_hw_params_set_buffer_time_near(pad->handle, hwparams,
+ &pad->buffer_time, 0) < 0)
+ return -E_SET_BUFFER_TIME;
+ if (snd_pcm_hw_params(pad->handle, hwparams) < 0)
+ return -E_HW_PARAMS;
+ snd_pcm_hw_params_get_period_size(hwparams, &period_size, 0);
+ snd_pcm_hw_params_get_buffer_size(hwparams, &buffer_size);
+ PARA_INFO_LOG("buffer size: %lu, period_size: %lu\n", buffer_size,
+ period_size);
+ 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)
+ start_threshold = 1;
+ if (snd_pcm_sw_params_set_start_threshold(pad->handle, swparams,
+ start_threshold) < 0)
+ return -E_START_THRESHOLD;
+ stop_threshold = buffer_size;
+ 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;
+ pad->bytes_per_frame = snd_pcm_format_physical_width(FORMAT)
+ * pad->channels / 8;
+ if (snd_pcm_nonblock(pad->handle, 1))
+ PARA_ERROR_LOG("%s\n", "failed to set nonblock mode");
+ return period_size * pad->bytes_per_frame;
+}
+
+static int alsa_write_pre_select(struct sched *s, struct writer_node *wn)
+{
+ struct private_alsa_write_data *pad = wn->private_data;
+ struct writer_node_group *wng = wn->wng;
+ struct timeval diff;
+
+ if (*wng->loaded < pad->bytes_per_frame)
+ return 1;
+ if (tv_diff(now, &pad->next_chunk, &diff) < 0) {
+ if (tv_diff(&s->timeout, &diff, NULL) > 0)
+ s->timeout = diff;
+ } else {
+ s->timeout.tv_sec = 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 writer_node *wn)
+{
+ 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;
+ unsigned char *data = (unsigned char*)wng->buf + wn->written;
+ struct timeval tv;
+
+// PARA_INFO_LOG("%zd frames\n", frames);
+ if (!frames) {
+ if (*wng->input_eof)
+ wn->written = *wng->loaded;
+ return 1;
+ }
+ if (tv_diff(now, &pad->next_chunk, NULL) < 0)
+ return 1;
+ ret = snd_pcm_writei(pad->handle, data, frames);
+ if (ret == -EPIPE) {
+ PARA_WARNING_LOG("%s", "EPIPE\n");
+ snd_pcm_prepare(pad->handle);
+ return 1;
+ }
+ if (ret < 0) {
+ PARA_WARNING_LOG("%s", "ALSA ERROR\n");
+ 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;
+ return 1;
+}
+
+static void alsa_close(struct writer_node *wn)
+{
+ 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();
+ free(pad);
+}
+
+__malloc void *alsa_parse_config(char *options)
+{
+ 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");
+ if (ret)
+ goto err_out;
+ PARA_INFO_LOG("help given: %d\n", conf->help_given);
+ return conf;
+err_out:
+ free(conf);
+ return NULL;
+}
+
+/** the init function of the alsa writer */
+void alsa_write_init(struct writer *w)
+{
+ 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 */
+}
projects / paraslash.git / blobdiff