1 /*
2  * ALSA input and output
3  * Copyright (c) 2007 Luca Abeni ( lucabe72 email it )
4  * Copyright (c) 2007 Benoit Fouet ( benoit fouet free fr )
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 /**
24  * @file
25  * ALSA input and output: common code
26  * @author Luca Abeni ( lucabe72 email it )
27  * @author Benoit Fouet ( benoit fouet free fr )
28  * @author Nicolas George ( nicolas george normalesup org )
29  */
30 
31 #include <alsa/asoundlib.h>
32 #include "avdevice.h"
33 #include "libavutil/avassert.h"
34 #include "libavutil/channel_layout.h"
35 
36 #include "alsa.h"
37 
codec_id_to_pcm_format(int codec_id)38 static av_cold snd_pcm_format_t codec_id_to_pcm_format(int codec_id)
39 {
40     switch(codec_id) {
41         case AV_CODEC_ID_PCM_F64LE: return SND_PCM_FORMAT_FLOAT64_LE;
42         case AV_CODEC_ID_PCM_F64BE: return SND_PCM_FORMAT_FLOAT64_BE;
43         case AV_CODEC_ID_PCM_F32LE: return SND_PCM_FORMAT_FLOAT_LE;
44         case AV_CODEC_ID_PCM_F32BE: return SND_PCM_FORMAT_FLOAT_BE;
45         case AV_CODEC_ID_PCM_S32LE: return SND_PCM_FORMAT_S32_LE;
46         case AV_CODEC_ID_PCM_S32BE: return SND_PCM_FORMAT_S32_BE;
47         case AV_CODEC_ID_PCM_U32LE: return SND_PCM_FORMAT_U32_LE;
48         case AV_CODEC_ID_PCM_U32BE: return SND_PCM_FORMAT_U32_BE;
49         case AV_CODEC_ID_PCM_S24LE: return SND_PCM_FORMAT_S24_3LE;
50         case AV_CODEC_ID_PCM_S24BE: return SND_PCM_FORMAT_S24_3BE;
51         case AV_CODEC_ID_PCM_U24LE: return SND_PCM_FORMAT_U24_3LE;
52         case AV_CODEC_ID_PCM_U24BE: return SND_PCM_FORMAT_U24_3BE;
53         case AV_CODEC_ID_PCM_S16LE: return SND_PCM_FORMAT_S16_LE;
54         case AV_CODEC_ID_PCM_S16BE: return SND_PCM_FORMAT_S16_BE;
55         case AV_CODEC_ID_PCM_U16LE: return SND_PCM_FORMAT_U16_LE;
56         case AV_CODEC_ID_PCM_U16BE: return SND_PCM_FORMAT_U16_BE;
57         case AV_CODEC_ID_PCM_S8:    return SND_PCM_FORMAT_S8;
58         case AV_CODEC_ID_PCM_U8:    return SND_PCM_FORMAT_U8;
59         case AV_CODEC_ID_PCM_MULAW: return SND_PCM_FORMAT_MU_LAW;
60         case AV_CODEC_ID_PCM_ALAW:  return SND_PCM_FORMAT_A_LAW;
61         default:                 return SND_PCM_FORMAT_UNKNOWN;
62     }
63 }
64 
65 #define MAKE_REORDER_FUNC(NAME, TYPE, CHANNELS, LAYOUT, MAP)                \
66 static void alsa_reorder_ ## NAME ## _ ## LAYOUT(const void *in_v,          \
67                                                  void *out_v,               \
68                                                  int n)                     \
69 {                                                                           \
70     const TYPE *in = in_v;                                                  \
71     TYPE      *out = out_v;                                                 \
72                                                                             \
73     while (n-- > 0) {                                                       \
74         MAP                                                                 \
75         in  += CHANNELS;                                                    \
76         out += CHANNELS;                                                    \
77     }                                                                       \
78 }
79 
80 #define MAKE_REORDER_FUNCS(CHANNELS, LAYOUT, MAP) \
81     MAKE_REORDER_FUNC(int8,  int8_t,  CHANNELS, LAYOUT, MAP) \
82     MAKE_REORDER_FUNC(int16, int16_t, CHANNELS, LAYOUT, MAP) \
83     MAKE_REORDER_FUNC(int32, int32_t, CHANNELS, LAYOUT, MAP) \
84     MAKE_REORDER_FUNC(f32,   float,   CHANNELS, LAYOUT, MAP)
85 
86 MAKE_REORDER_FUNCS(5, out_50, \
87         out[0] = in[0]; \
88         out[1] = in[1]; \
89         out[2] = in[3]; \
90         out[3] = in[4]; \
91         out[4] = in[2]; \
92         )
93 
94 MAKE_REORDER_FUNCS(6, out_51, \
95         out[0] = in[0]; \
96         out[1] = in[1]; \
97         out[2] = in[4]; \
98         out[3] = in[5]; \
99         out[4] = in[2]; \
100         out[5] = in[3]; \
101         )
102 
103 MAKE_REORDER_FUNCS(8, out_71, \
104         out[0] = in[0]; \
105         out[1] = in[1]; \
106         out[2] = in[4]; \
107         out[3] = in[5]; \
108         out[4] = in[2]; \
109         out[5] = in[3]; \
110         out[6] = in[6]; \
111         out[7] = in[7]; \
112         )
113 
114 #define FORMAT_I8  0
115 #define FORMAT_I16 1
116 #define FORMAT_I32 2
117 #define FORMAT_F32 3
118 
119 #define PICK_REORDER(layout)\
120 switch(format) {\
121     case FORMAT_I8:  s->reorder_func = alsa_reorder_int8_out_ ##layout;  break;\
122     case FORMAT_I16: s->reorder_func = alsa_reorder_int16_out_ ##layout; break;\
123     case FORMAT_I32: s->reorder_func = alsa_reorder_int32_out_ ##layout; break;\
124     case FORMAT_F32: s->reorder_func = alsa_reorder_f32_out_ ##layout;   break;\
125 }
126 
find_reorder_func(AlsaData * s,int codec_id,uint64_t layout,int out)127 static av_cold int find_reorder_func(AlsaData *s, int codec_id, uint64_t layout, int out)
128 {
129     int format;
130 
131     /* reordering input is not currently supported */
132     if (!out)
133         return AVERROR(ENOSYS);
134 
135     /* reordering is not needed for QUAD or 2_2 layout */
136     if (layout == AV_CH_LAYOUT_QUAD || layout == AV_CH_LAYOUT_2_2)
137         return 0;
138 
139     switch (codec_id) {
140     case AV_CODEC_ID_PCM_S8:
141     case AV_CODEC_ID_PCM_U8:
142     case AV_CODEC_ID_PCM_ALAW:
143     case AV_CODEC_ID_PCM_MULAW: format = FORMAT_I8;  break;
144     case AV_CODEC_ID_PCM_S16LE:
145     case AV_CODEC_ID_PCM_S16BE:
146     case AV_CODEC_ID_PCM_U16LE:
147     case AV_CODEC_ID_PCM_U16BE: format = FORMAT_I16; break;
148     case AV_CODEC_ID_PCM_S32LE:
149     case AV_CODEC_ID_PCM_S32BE:
150     case AV_CODEC_ID_PCM_U32LE:
151     case AV_CODEC_ID_PCM_U32BE: format = FORMAT_I32; break;
152     case AV_CODEC_ID_PCM_F32LE:
153     case AV_CODEC_ID_PCM_F32BE: format = FORMAT_F32; break;
154     default:                 return AVERROR(ENOSYS);
155     }
156 
157     if      (layout == AV_CH_LAYOUT_5POINT0_BACK || layout == AV_CH_LAYOUT_5POINT0)
158         PICK_REORDER(50)
159     else if (layout == AV_CH_LAYOUT_5POINT1_BACK || layout == AV_CH_LAYOUT_5POINT1)
160         PICK_REORDER(51)
161     else if (layout == AV_CH_LAYOUT_7POINT1)
162         PICK_REORDER(71)
163 
164     return s->reorder_func ? 0 : AVERROR(ENOSYS);
165 }
166 
ff_alsa_open(AVFormatContext * ctx,snd_pcm_stream_t mode,unsigned int * sample_rate,int channels,enum AVCodecID * codec_id)167 av_cold int ff_alsa_open(AVFormatContext *ctx, snd_pcm_stream_t mode,
168                          unsigned int *sample_rate,
169                          int channels, enum AVCodecID *codec_id)
170 {
171     AlsaData *s = ctx->priv_data;
172     const char *audio_device;
173     int res, flags = 0;
174     snd_pcm_format_t format;
175     snd_pcm_t *h;
176     snd_pcm_hw_params_t *hw_params;
177     snd_pcm_uframes_t buffer_size, period_size;
178     uint64_t layout = ctx->streams[0]->codecpar->channel_layout;
179 
180     if (ctx->url[0] == 0) audio_device = "default";
181     else                  audio_device = ctx->url;
182 
183     if (*codec_id == AV_CODEC_ID_NONE)
184         *codec_id = DEFAULT_CODEC_ID;
185     format = codec_id_to_pcm_format(*codec_id);
186     if (format == SND_PCM_FORMAT_UNKNOWN) {
187         av_log(ctx, AV_LOG_ERROR, "sample format 0x%04x is not supported\n", *codec_id);
188         return AVERROR(ENOSYS);
189     }
190     s->frame_size = av_get_bits_per_sample(*codec_id) / 8 * channels;
191 
192     if (ctx->flags & AVFMT_FLAG_NONBLOCK) {
193         flags = SND_PCM_NONBLOCK;
194     }
195     res = snd_pcm_open(&h, audio_device, mode, flags);
196     if (res < 0) {
197         av_log(ctx, AV_LOG_ERROR, "cannot open audio device %s (%s)\n",
198                audio_device, snd_strerror(res));
199         return AVERROR(EIO);
200     }
201 
202     res = snd_pcm_hw_params_malloc(&hw_params);
203     if (res < 0) {
204         av_log(ctx, AV_LOG_ERROR, "cannot allocate hardware parameter structure (%s)\n",
205                snd_strerror(res));
206         goto fail1;
207     }
208 
209     res = snd_pcm_hw_params_any(h, hw_params);
210     if (res < 0) {
211         av_log(ctx, AV_LOG_ERROR, "cannot initialize hardware parameter structure (%s)\n",
212                snd_strerror(res));
213         goto fail;
214     }
215 
216     res = snd_pcm_hw_params_set_access(h, hw_params, SND_PCM_ACCESS_RW_INTERLEAVED);
217     if (res < 0) {
218         av_log(ctx, AV_LOG_ERROR, "cannot set access type (%s)\n",
219                snd_strerror(res));
220         goto fail;
221     }
222 
223     res = snd_pcm_hw_params_set_format(h, hw_params, format);
224     if (res < 0) {
225         av_log(ctx, AV_LOG_ERROR, "cannot set sample format 0x%04x %d (%s)\n",
226                *codec_id, format, snd_strerror(res));
227         goto fail;
228     }
229 
230     res = snd_pcm_hw_params_set_rate_near(h, hw_params, sample_rate, 0);
231     if (res < 0) {
232         av_log(ctx, AV_LOG_ERROR, "cannot set sample rate (%s)\n",
233                snd_strerror(res));
234         goto fail;
235     }
236 
237     res = snd_pcm_hw_params_set_channels(h, hw_params, channels);
238     if (res < 0) {
239         av_log(ctx, AV_LOG_ERROR, "cannot set channel count to %d (%s)\n",
240                channels, snd_strerror(res));
241         goto fail;
242     }
243 
244     snd_pcm_hw_params_get_buffer_size_max(hw_params, &buffer_size);
245     buffer_size = FFMIN(buffer_size, ALSA_BUFFER_SIZE_MAX);
246     /* TODO: maybe use ctx->max_picture_buffer somehow */
247     res = snd_pcm_hw_params_set_buffer_size_near(h, hw_params, &buffer_size);
248     if (res < 0) {
249         av_log(ctx, AV_LOG_ERROR, "cannot set ALSA buffer size (%s)\n",
250                snd_strerror(res));
251         goto fail;
252     }
253 
254     snd_pcm_hw_params_get_period_size_min(hw_params, &period_size, NULL);
255     if (!period_size)
256         period_size = buffer_size / 4;
257     res = snd_pcm_hw_params_set_period_size_near(h, hw_params, &period_size, NULL);
258     if (res < 0) {
259         av_log(ctx, AV_LOG_ERROR, "cannot set ALSA period size (%s)\n",
260                snd_strerror(res));
261         goto fail;
262     }
263     s->period_size = period_size;
264 
265     res = snd_pcm_hw_params(h, hw_params);
266     if (res < 0) {
267         av_log(ctx, AV_LOG_ERROR, "cannot set parameters (%s)\n",
268                snd_strerror(res));
269         goto fail;
270     }
271 
272     snd_pcm_hw_params_free(hw_params);
273 
274     if (channels > 2 && layout) {
275         if (find_reorder_func(s, *codec_id, layout, mode == SND_PCM_STREAM_PLAYBACK) < 0) {
276             char name[128];
277             av_get_channel_layout_string(name, sizeof(name), channels, layout);
278             av_log(ctx, AV_LOG_WARNING, "ALSA channel layout unknown or unimplemented for %s %s.\n",
279                    name, mode == SND_PCM_STREAM_PLAYBACK ? "playback" : "capture");
280         }
281         if (s->reorder_func) {
282             s->reorder_buf_size = buffer_size;
283             s->reorder_buf = av_malloc_array(s->reorder_buf_size, s->frame_size);
284             if (!s->reorder_buf)
285                 goto fail1;
286         }
287     }
288 
289     s->h = h;
290     return 0;
291 
292 fail:
293     snd_pcm_hw_params_free(hw_params);
294 fail1:
295     snd_pcm_close(h);
296     return AVERROR(EIO);
297 }
298 
ff_alsa_close(AVFormatContext * s1)299 av_cold int ff_alsa_close(AVFormatContext *s1)
300 {
301     AlsaData *s = s1->priv_data;
302 
303     snd_pcm_nonblock(s->h, 0);
304     snd_pcm_drain(s->h);
305     av_freep(&s->reorder_buf);
306     if (CONFIG_ALSA_INDEV)
307         ff_timefilter_destroy(s->timefilter);
308     snd_pcm_close(s->h);
309     return 0;
310 }
311 
ff_alsa_xrun_recover(AVFormatContext * s1,int err)312 int ff_alsa_xrun_recover(AVFormatContext *s1, int err)
313 {
314     AlsaData *s = s1->priv_data;
315     snd_pcm_t *handle = s->h;
316 
317     av_log(s1, AV_LOG_WARNING, "ALSA buffer xrun.\n");
318     if (err == -EPIPE) {
319         err = snd_pcm_prepare(handle);
320         if (err < 0) {
321             av_log(s1, AV_LOG_ERROR, "cannot recover from underrun (snd_pcm_prepare failed: %s)\n", snd_strerror(err));
322 
323             return AVERROR(EIO);
324         }
325     } else if (err == -ESTRPIPE) {
326         av_log(s1, AV_LOG_ERROR, "-ESTRPIPE... Unsupported!\n");
327 
328         return -1;
329     }
330     return err;
331 }
332 
ff_alsa_extend_reorder_buf(AlsaData * s,int min_size)333 int ff_alsa_extend_reorder_buf(AlsaData *s, int min_size)
334 {
335     int size = s->reorder_buf_size;
336     void *r;
337 
338     av_assert0(size != 0);
339     while (size < min_size)
340         size *= 2;
341     r = av_realloc_array(s->reorder_buf, size, s->frame_size);
342     if (!r)
343         return AVERROR(ENOMEM);
344     s->reorder_buf = r;
345     s->reorder_buf_size = size;
346     return 0;
347 }
348 
349 /* ported from alsa-utils/aplay.c */
ff_alsa_get_device_list(AVDeviceInfoList * device_list,snd_pcm_stream_t stream_type)350 int ff_alsa_get_device_list(AVDeviceInfoList *device_list, snd_pcm_stream_t stream_type)
351 {
352     int ret = 0;
353     void **hints, **n;
354     char *name = NULL, *descr = NULL, *io = NULL, *tmp;
355     AVDeviceInfo *new_device = NULL;
356     const char *filter = stream_type == SND_PCM_STREAM_PLAYBACK ? "Output" : "Input";
357 
358     if (snd_device_name_hint(-1, "pcm", &hints) < 0)
359         return AVERROR_EXTERNAL;
360     n = hints;
361     while (*n && !ret) {
362         name = snd_device_name_get_hint(*n, "NAME");
363         descr = snd_device_name_get_hint(*n, "DESC");
364         io = snd_device_name_get_hint(*n, "IOID");
365         if (!io || !strcmp(io, filter)) {
366             new_device = av_mallocz(sizeof(AVDeviceInfo));
367             if (!new_device) {
368                 ret = AVERROR(ENOMEM);
369                 goto fail;
370             }
371             new_device->device_name = av_strdup(name);
372             if ((tmp = strrchr(descr, '\n')) && tmp[1])
373                 new_device->device_description = av_strdup(&tmp[1]);
374             else
375                 new_device->device_description = av_strdup(descr);
376             if (!new_device->device_description || !new_device->device_name) {
377                 ret = AVERROR(ENOMEM);
378                 goto fail;
379             }
380             if ((ret = av_dynarray_add_nofree(&device_list->devices,
381                                               &device_list->nb_devices, new_device)) < 0) {
382                 goto fail;
383             }
384             if (!strcmp(new_device->device_name, "default"))
385                 device_list->default_device = device_list->nb_devices - 1;
386             new_device = NULL;
387         }
388       fail:
389         free(io);
390         free(name);
391         free(descr);
392         n++;
393     }
394     if (new_device) {
395         av_free(new_device->device_description);
396         av_free(new_device->device_name);
397         av_free(new_device);
398     }
399     snd_device_name_free_hint(hints);
400     return ret;
401 }
402