Commit | Line | Data |
---|---|---|
32d23d03 GI |
1 | /* |
2 | * (C) notaz, 2013 | |
3 | * | |
4 | * This work is licensed under the terms of any of these licenses | |
5 | * (at your option): | |
6 | * - GNU GPL, version 2 or later. | |
7 | * - GNU LGPL, version 2.1 or later. | |
8 | * - MAME license. | |
9 | * See the COPYING file in the top-level directory. | |
10 | */ | |
11 | ||
12 | #include <stdio.h> | |
13 | #include <alsa/asoundlib.h> | |
14 | #include <unistd.h> | |
15 | ||
16 | #include "sndout_alsa.h" | |
17 | ||
9028744c | 18 | #define PFX "sndout_alsa: " |
19 | ||
32d23d03 GI |
20 | static snd_pcm_t *handle; |
21 | static snd_pcm_uframes_t buffer_size, period_size; | |
32d23d03 | 22 | static void *silent_period; |
9028744c | 23 | static unsigned int channels; |
24 | static int failure_counter; | |
32d23d03 GI |
25 | |
26 | int sndout_alsa_init(void) | |
27 | { | |
28 | int ret; | |
29 | ||
30 | ret = snd_pcm_open(&handle, "default", SND_PCM_STREAM_PLAYBACK, 0); | |
31 | if (ret != 0) | |
32 | return -1; | |
33 | ||
34 | return 0; | |
35 | } | |
36 | ||
37 | int sndout_alsa_start(int rate_, int stereo) | |
38 | { | |
39 | snd_pcm_hw_params_t *hwparams = NULL; | |
40 | unsigned int rate = rate_; | |
41 | int samples, shift; | |
42 | int ret; | |
43 | ||
44 | samples = rate * 40 / 1000; | |
45 | for (shift = 8; (1 << shift) < samples; shift++) | |
46 | ; | |
47 | period_size = 1 << shift; | |
48 | buffer_size = 8 * period_size; | |
49 | ||
50 | snd_pcm_hw_params_alloca(&hwparams); | |
51 | ||
52 | ret = snd_pcm_hw_params_any(handle, hwparams); | |
53 | ret |= snd_pcm_hw_params_set_access(handle, hwparams, SND_PCM_ACCESS_RW_INTERLEAVED); | |
54 | ret |= snd_pcm_hw_params_set_format(handle, hwparams, SND_PCM_FORMAT_S16_LE); | |
55 | ret |= snd_pcm_hw_params_set_channels(handle, hwparams, stereo ? 2 : 1); | |
56 | ret |= snd_pcm_hw_params_set_rate_near(handle, hwparams, &rate, 0); | |
57 | ret |= snd_pcm_hw_params_set_buffer_size_near(handle, hwparams, &buffer_size); | |
58 | ret |= snd_pcm_hw_params_set_period_size_near(handle, hwparams, &period_size, NULL); | |
59 | ||
60 | if (ret != 0) { | |
9028744c | 61 | fprintf(stderr, PFX "failed to set hwparams\n"); |
62 | goto fail; | |
32d23d03 GI |
63 | } |
64 | ||
65 | ret = snd_pcm_hw_params(handle, hwparams); | |
66 | if (ret != 0) { | |
9028744c | 67 | fprintf(stderr, PFX "failed to apply hwparams: %d\n", ret); |
68 | goto fail; | |
32d23d03 GI |
69 | } |
70 | ||
71 | snd_pcm_hw_params_get_buffer_size(hwparams, &buffer_size); | |
72 | snd_pcm_hw_params_get_period_size(hwparams, &period_size, NULL); | |
73 | snd_pcm_hw_params_get_channels(hwparams, &channels); | |
74 | ||
9b87077e | 75 | silent_period = calloc(period_size * channels, 2); |
32d23d03 | 76 | |
9028744c | 77 | ret = snd_pcm_prepare(handle); |
78 | if (ret != 0) { | |
79 | fprintf(stderr, PFX "snd_pcm_prepare failed: %d\n", ret); | |
80 | goto fail; | |
81 | } | |
32d23d03 | 82 | |
9028744c | 83 | ret = snd_pcm_start(handle); |
32d23d03 | 84 | if (ret != 0) { |
9028744c | 85 | fprintf(stderr, PFX "snd_pcm_start failed: %d\n", ret); |
86 | goto fail; | |
32d23d03 GI |
87 | } |
88 | ||
9028744c | 89 | failure_counter = 0; |
90 | ||
32d23d03 | 91 | return 0; |
9028744c | 92 | |
93 | fail: | |
94 | // to flush out redirected logs | |
95 | fflush(stdout); | |
96 | fflush(stderr); | |
97 | return -1; | |
32d23d03 GI |
98 | } |
99 | ||
100 | void sndout_alsa_stop(void) | |
101 | { | |
9028744c | 102 | int ret = snd_pcm_drop(handle); |
103 | if (ret != 0) | |
104 | fprintf(stderr, PFX "snd_pcm_drop failed: %d\n", ret); | |
9b87077e | 105 | |
106 | free(silent_period); | |
107 | silent_period = NULL; | |
32d23d03 GI |
108 | } |
109 | ||
110 | void sndout_alsa_wait(void) | |
111 | { | |
112 | snd_pcm_sframes_t left; | |
113 | ||
114 | while (1) | |
115 | { | |
116 | left = snd_pcm_avail(handle); | |
117 | if (left < 0 || left >= buffer_size / 2) | |
118 | break; | |
119 | ||
120 | usleep(4000); | |
121 | } | |
122 | } | |
123 | ||
124 | int sndout_alsa_write_nb(const void *samples, int len) | |
125 | { | |
126 | snd_pcm_sframes_t left; | |
127 | int ret; | |
128 | ||
129 | len /= 2; | |
130 | if (channels == 2) | |
131 | len /= 2; | |
132 | ||
133 | left = snd_pcm_avail(handle); | |
134 | if (left >= 0 && left < len) | |
135 | return 0; | |
136 | ||
137 | ret = snd_pcm_writei(handle, samples, len); | |
138 | if (ret < 0) { | |
139 | ret = snd_pcm_recover(handle, ret, 1); | |
9028744c | 140 | if (ret != 0 && failure_counter++ < 5) |
141 | fprintf(stderr, PFX "snd_pcm_recover: %d\n", ret); | |
32d23d03 GI |
142 | |
143 | if (silent_period) | |
144 | snd_pcm_writei(handle, silent_period, period_size); | |
145 | snd_pcm_writei(handle, samples, len); | |
146 | } | |
147 | ||
148 | return len; | |
149 | } | |
150 | ||
151 | void sndout_alsa_exit(void) | |
152 | { | |
153 | snd_pcm_close(handle); | |
154 | handle = NULL; | |
155 | } |