command.c: cast members of struct timeval to long unsigned
[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 "write.h"
31
32 #include <alsa/asoundlib.h>
33
34 #include "write.cmdline.h"
35 #include "error.h"
36
37 extern struct gengetopt_args_info conf;
38
39 #define FORMAT SND_PCM_FORMAT_S16_LE
40
41 /** data specific to the alsa writer */
42 struct private_alsa_data {
43 snd_pcm_t *handle;
44 size_t bytes_per_frame;
45 };
46
47 /*
48 * open and prepare the PCM handle for writing
49 *
50 * Install PCM software and hardware configuration. Exit on errors.
51 */
52 static int alsa_open(struct writer_node *w)
53 {
54 snd_pcm_hw_params_t *hwparams;
55 snd_pcm_sw_params_t *swparams;
56 snd_pcm_uframes_t buffer_size, xfer_align, start_threshold,
57 stop_threshold;
58 unsigned buffer_time = 0;
59 int err;
60 snd_pcm_info_t *info;
61 snd_output_t *log;
62 snd_pcm_uframes_t period_size;
63 struct private_alsa_data *pad = para_malloc(sizeof(struct private_alsa_data));
64 w->private_data = pad;
65
66 snd_pcm_info_alloca(&info);
67 if (snd_output_stdio_attach(&log, stderr, 0) < 0)
68 return -E_ALSA_LOG;
69 err = snd_pcm_open(&pad->handle, conf.device_arg,
70 SND_PCM_STREAM_PLAYBACK, 0);
71 if (err < 0)
72 return -E_PCM_OPEN;
73 if ((err = snd_pcm_info(pad->handle, info)) < 0)
74 return -E_SND_PCM_INFO;
75
76 snd_pcm_hw_params_alloca(&hwparams);
77 snd_pcm_sw_params_alloca(&swparams);
78 if (snd_pcm_hw_params_any(pad->handle, hwparams) < 0)
79 return -E_BROKEN_CONF;
80 if (snd_pcm_hw_params_set_access(pad->handle, hwparams,
81 SND_PCM_ACCESS_RW_INTERLEAVED) < 0)
82 return -E_ACCESS_TYPE;
83 if (snd_pcm_hw_params_set_format(pad->handle, hwparams, FORMAT) < 0)
84 return -E_SAMPLE_FORMAT;
85 if (snd_pcm_hw_params_set_channels(pad->handle, hwparams,
86 conf.channels_arg) < 0)
87 return -E_CHANNEL_COUNT;
88 if (snd_pcm_hw_params_set_rate_near(pad->handle, hwparams,
89 (unsigned int*) &conf.sample_rate_arg, 0) < 0)
90 return -E_SET_RATE;
91 err = snd_pcm_hw_params_get_buffer_time_max(hwparams, &buffer_time, 0);
92 if (err < 0 || !buffer_time)
93 return -E_GET_BUFFER_TIME;
94 PARA_DEBUG_LOG("buffer time: %d\n", buffer_time);
95 if (snd_pcm_hw_params_set_buffer_time_near(pad->handle, hwparams,
96 &buffer_time, 0) < 0)
97 return -E_SET_BUFFER_TIME;
98 if (snd_pcm_hw_params(pad->handle, hwparams) < 0)
99 return -E_HW_PARAMS;
100 snd_pcm_hw_params_get_period_size(hwparams, &period_size, 0);
101 snd_pcm_hw_params_get_buffer_size(hwparams, &buffer_size);
102 PARA_DEBUG_LOG("buffer size: %lu, period_size: %lu\n", buffer_size,
103 period_size);
104 if (period_size == buffer_size)
105 return -E_BAD_PERIOD;
106 snd_pcm_sw_params_current(pad->handle, swparams);
107 err = snd_pcm_sw_params_get_xfer_align(swparams, &xfer_align);
108 if (err < 0 || !xfer_align)
109 return -E_GET_XFER;
110 snd_pcm_sw_params_set_avail_min(pad->handle, swparams, period_size);
111 /* round to closest transfer boundary */
112 start_threshold = (buffer_size / xfer_align) * xfer_align;
113 if (start_threshold < 1)
114 start_threshold = 1;
115 if (snd_pcm_sw_params_set_start_threshold(pad->handle, swparams,
116 start_threshold) < 0)
117 return -E_START_THRESHOLD;
118 stop_threshold = buffer_size;
119 if (snd_pcm_sw_params_set_stop_threshold(pad->handle, swparams,
120 stop_threshold) < 0)
121 return -E_STOP_THRESHOLD;
122 if (snd_pcm_sw_params_set_xfer_align(pad->handle, swparams,
123 xfer_align) < 0)
124 return -E_SET_XFER;
125 if (snd_pcm_sw_params(pad->handle, swparams) < 0)
126 return -E_SW_PARAMS;
127 pad->bytes_per_frame = snd_pcm_format_physical_width(FORMAT)
128 * conf.channels_arg / 8;
129 return period_size * pad->bytes_per_frame;
130 }
131
132 /**
133 * push out pcm frames
134 * \param data pointer do data to be written
135 * \param nbytes number of bytes (not frames)
136 *
137 * \return Number of bytes written, -E_ALSA_WRITE on errors.
138 */
139 static int alsa_write(char *data, size_t nbytes, struct writer_node *wn)
140 {
141 struct private_alsa_data *pad = wn->private_data;
142 size_t frames = nbytes / pad->bytes_per_frame;
143 unsigned char *d = data;
144 snd_pcm_sframes_t r, result = 0;
145
146 while (frames > 0) {
147 /* write interleaved frames */
148 r = snd_pcm_writei(pad->handle, d, frames);
149 if (r < 0)
150 PARA_ERROR_LOG("write error: %s\n", snd_strerror(r));
151 if (r == -EAGAIN || (r >= 0 && r < frames))
152 snd_pcm_wait(pad->handle, 1);
153 else if (r == -EPIPE)
154 snd_pcm_prepare(pad->handle);
155 else if (r < 0)
156 return -E_ALSA_WRITE;
157 if (r > 0) {
158 result += r;
159 frames -= r;
160 d += r * pad->bytes_per_frame;
161 }
162 }
163 return result * pad->bytes_per_frame;
164 }
165
166 static void alsa_close(struct writer_node *wn)
167 {
168 struct private_alsa_data *pad = wn->private_data;
169 snd_pcm_drain(pad->handle);
170 snd_pcm_close(pad->handle);
171 snd_config_update_free_global();
172 free(pad);
173 }
174
175 void alsa_writer_init(struct writer *w)
176 {
177 w->open = alsa_open;
178 w->write = alsa_write;
179 w->close = alsa_close;
180 w->shutdown = NULL; /* nothing to do */
181 }