simplify osx_write_post_select()
[paraslash.git] / alsa_writer.c
1 /*
2 * Copyright (C) 2005-2006 Andre Noll <maan@systemlinux.org>
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
17 */
18
19 /** \file alsa_writer.c paraslash's alsa output plugin */
20
21 /*
22 * Based in parts on aplay.c from the alsa-utils-1.0.8 package,
23 * Copyright (c) by Jaroslav Kysela <perex@suse.cz>, which is
24 * based on the vplay program by Michael Beck.
25 */
26
27 #include "para.h"
28 #include "fd.h"
29 #include "string.h"
30 #include "list.h"
31 #include "sched.h"
32 #include "write.h"
33
34 #include <alsa/asoundlib.h>
35
36 #include "alsa_write.cmdline.h"
37 #include "error.h"
38
39
40 #define FORMAT SND_PCM_FORMAT_S16_LE
41
42 /** data specific to the alsa writer */
43 struct private_alsa_data {
44 /** the alsa handle */
45 snd_pcm_t *handle;
46 /** determined and set by alsa_open() */
47 size_t bytes_per_frame;
48 /** don't write anything until this time */
49 struct timeval next_chunk;
50 /** the return value of snd_pcm_hw_params_get_buffer_time_max() */
51 unsigned buffer_time;
52 unsigned samplerate;
53 unsigned channels;
54 };
55
56 /*
57 * open and prepare the PCM handle for writing
58 *
59 * Install PCM software and hardware configuration. Exit on errors.
60 */
61 static int alsa_open(struct writer_node *w)
62 {
63 snd_pcm_hw_params_t *hwparams;
64 snd_pcm_sw_params_t *swparams;
65 snd_pcm_uframes_t buffer_size, xfer_align, start_threshold,
66 stop_threshold;
67 int err;
68 snd_pcm_info_t *info;
69 snd_pcm_uframes_t period_size;
70 struct private_alsa_data *pad = para_calloc(sizeof(struct private_alsa_data));
71 struct alsa_write_args_info *conf = w->conf;
72 struct writer_node_group *wng = w->wng;
73
74 if (!conf->samplerate_given && wng->samplerate)
75 pad->samplerate = *wng->samplerate;
76 else
77 pad->samplerate = conf->samplerate_arg;
78 if (!conf->channels_given && wng->channels)
79 pad->channels = *wng->channels;
80 else
81 pad->channels = conf->channels_arg;
82 PARA_INFO_LOG("%d channel(s), %dHz\n", pad->channels, pad->samplerate);
83 w->private_data = pad;
84 snd_pcm_info_alloca(&info);
85 err = snd_pcm_open(&pad->handle, conf->device_arg,
86 SND_PCM_STREAM_PLAYBACK, SND_PCM_NONBLOCK);
87 if (err < 0)
88 return -E_PCM_OPEN;
89 if ((err = snd_pcm_info(pad->handle, info)) < 0)
90 return -E_SND_PCM_INFO;
91
92 snd_pcm_hw_params_alloca(&hwparams);
93 snd_pcm_sw_params_alloca(&swparams);
94 if (snd_pcm_hw_params_any(pad->handle, hwparams) < 0)
95 return -E_BROKEN_CONF;
96 if (snd_pcm_hw_params_set_access(pad->handle, hwparams,
97 SND_PCM_ACCESS_RW_INTERLEAVED) < 0)
98 return -E_ACCESS_TYPE;
99 if (snd_pcm_hw_params_set_format(pad->handle, hwparams, FORMAT) < 0)
100 return -E_SAMPLE_FORMAT;
101 if (snd_pcm_hw_params_set_channels(pad->handle, hwparams,
102 pad->channels) < 0)
103 return -E_CHANNEL_COUNT;
104 if (snd_pcm_hw_params_set_rate_near(pad->handle, hwparams,
105 &pad->samplerate, 0) < 0)
106 return -E_SET_RATE;
107 err = snd_pcm_hw_params_get_buffer_time_max(hwparams, &pad->buffer_time, 0);
108 if (err < 0 || !pad->buffer_time)
109 return -E_GET_BUFFER_TIME;
110 PARA_INFO_LOG("buffer time: %d\n", pad->buffer_time);
111 if (snd_pcm_hw_params_set_buffer_time_near(pad->handle, hwparams,
112 &pad->buffer_time, 0) < 0)
113 return -E_SET_BUFFER_TIME;
114 if (snd_pcm_hw_params(pad->handle, hwparams) < 0)
115 return -E_HW_PARAMS;
116 snd_pcm_hw_params_get_period_size(hwparams, &period_size, 0);
117 snd_pcm_hw_params_get_buffer_size(hwparams, &buffer_size);
118 PARA_INFO_LOG("buffer size: %lu, period_size: %lu\n", buffer_size,
119 period_size);
120 if (period_size == buffer_size)
121 return -E_BAD_PERIOD;
122 snd_pcm_sw_params_current(pad->handle, swparams);
123 err = snd_pcm_sw_params_get_xfer_align(swparams, &xfer_align);
124 if (err < 0 || !xfer_align)
125 return -E_GET_XFER;
126 snd_pcm_sw_params_set_avail_min(pad->handle, swparams, period_size);
127 /* round to closest transfer boundary */
128 start_threshold = (buffer_size / xfer_align) * xfer_align;
129 if (start_threshold < 1)
130 start_threshold = 1;
131 if (snd_pcm_sw_params_set_start_threshold(pad->handle, swparams,
132 start_threshold) < 0)
133 return -E_START_THRESHOLD;
134 stop_threshold = buffer_size;
135 if (snd_pcm_sw_params_set_stop_threshold(pad->handle, swparams,
136 stop_threshold) < 0)
137 return -E_STOP_THRESHOLD;
138 if (snd_pcm_sw_params_set_xfer_align(pad->handle, swparams,
139 xfer_align) < 0)
140 return -E_SET_XFER;
141 if (snd_pcm_sw_params(pad->handle, swparams) < 0)
142 return -E_SW_PARAMS;
143 pad->bytes_per_frame = snd_pcm_format_physical_width(FORMAT)
144 * pad->channels / 8;
145 if (snd_pcm_nonblock(pad->handle, 1))
146 PARA_ERROR_LOG("%s\n", "failed to set nonblock mode");
147 return period_size * pad->bytes_per_frame;
148 }
149
150 static int alsa_write_pre_select(struct sched *s, struct writer_node *wn)
151 {
152 struct private_alsa_data *pad = wn->private_data;
153 struct writer_node_group *wng = wn->wng;
154 struct timeval diff;
155
156 if (*wng->loaded < pad->bytes_per_frame)
157 return 1;
158 if (tv_diff(now, &pad->next_chunk, &diff) < 0) {
159 if (tv_diff(&s->timeout, &diff, NULL) > 0)
160 s->timeout = diff;
161 } else {
162 s->timeout.tv_sec = 0;
163 s->timeout.tv_usec = 1;
164 }
165 return 1;
166 // PARA_INFO_LOG("timeout: %lu\n", tv2ms(&s->timeout));
167 }
168
169 static int alsa_write_post_select(__a_unused struct sched *s,
170 struct writer_node *wn)
171 {
172 struct private_alsa_data *pad = wn->private_data;
173 struct writer_node_group *wng = wn->wng;
174 size_t frames = (*wng->loaded - wn->written) / pad->bytes_per_frame;
175 snd_pcm_sframes_t ret;
176 unsigned char *data = (unsigned char*)wng->buf + wn->written;
177 struct timeval tv;
178
179 // PARA_INFO_LOG("%zd frames\n", frames);
180 if (!frames) {
181 if (*wng->input_eof)
182 wn->written = *wng->loaded;
183 return 1;
184 }
185 if (tv_diff(now, &pad->next_chunk, NULL) < 0)
186 return 1;
187 ret = snd_pcm_writei(pad->handle, data, frames);
188 if (ret == -EPIPE) {
189 PARA_WARNING_LOG("%s", "EPIPE\n");
190 snd_pcm_prepare(pad->handle);
191 return 1;
192 }
193 if (ret < 0) {
194 PARA_WARNING_LOG("%s", "ALSA ERROR\n");
195 return -E_ALSA_WRITE;
196 }
197 ms2tv(pad->buffer_time / 4000, &tv);
198 // ms2tv(1, &tv);
199 tv_add(now, &tv, &pad->next_chunk);
200 wn->written += ret * pad->bytes_per_frame;
201 return 1;
202 }
203
204 static void alsa_close(struct writer_node *wn)
205 {
206 struct private_alsa_data *pad = wn->private_data;
207 PARA_INFO_LOG("closing writer node %p\n", wn);
208 snd_pcm_drain(pad->handle);
209 snd_pcm_close(pad->handle);
210 snd_config_update_free_global();
211 free(pad);
212 }
213
214 __malloc void *alsa_parse_config(char *options)
215 {
216 struct alsa_write_args_info *conf
217 = para_calloc(sizeof(struct alsa_write_args_info));
218 PARA_INFO_LOG("options: %s, %d\n", options, strcspn(options, " \t"));
219 int ret = alsa_cmdline_parser_string(options, conf, "alsa_write");
220 if (ret)
221 goto err_out;
222 PARA_INFO_LOG("help given: %d\n", conf->help_given);
223 return conf;
224 err_out:
225 free(conf);
226 return NULL;
227 }
228
229 /** the init function of the alsa writer */
230 void alsa_writer_init(struct writer *w)
231 {
232 w->open = alsa_open;
233 w->close = alsa_close;
234 w->pre_select = alsa_write_pre_select;
235 w->post_select = alsa_write_post_select;
236 w->parse_config = alsa_parse_config;
237 w->shutdown = NULL; /* nothing to do */
238 }