diff options
Diffstat (limited to 'plugins/alsa/alsa-core-pcm.c')
| -rw-r--r-- | plugins/alsa/alsa-core-pcm.c | 357 |
1 files changed, 357 insertions, 0 deletions
diff --git a/plugins/alsa/alsa-core-pcm.c b/plugins/alsa/alsa-core-pcm.c new file mode 100644 index 0000000..a08dfca --- /dev/null +++ b/plugins/alsa/alsa-core-pcm.c @@ -0,0 +1,357 @@ +/* + * Copyright(C) 2018 "IoT.bzh" + * Author Fulup Ar Foll <fulup@iot.bzh> + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http : //www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License + +for the specific language governing permissions and + * limitations under the License. + * + * reference : + * https://github.com/zonque/simple-alsa-loop/blob/master/loop.c + * https://www.alsa-project.org/alsa-doc/alsa-lib/_2test_2pcm_8c-example.html#a31 + * + */ + +#define _GNU_SOURCE // needed for vasprintf + +#include "alsa-softmixer.h" +#include <pthread.h> +#include <sys/syscall.h> + + + +#define BUFFER_FRAME_COUNT 1024 + +typedef struct { + snd_pcm_t *pcmIn; + snd_pcm_t *pcmOut; + AFB_ApiT api; + sd_event_source* evtsrc; + void* buffer; + size_t frameSize; + unsigned int frameCount; + unsigned int channels; + sd_event *sdLoop; + pthread_t thread; + int tid; + char* info; +} AlsaPcmCopyHandleT; + +STATIC int AlsaPeriodSize(snd_pcm_format_t pcmFormat) { + int pcmSampleSize; + + switch (pcmFormat) { + + case SND_PCM_FORMAT_S8: + case SND_PCM_FORMAT_U8: + pcmSampleSize = 1; + break; + + case SND_PCM_FORMAT_U16_LE: + case SND_PCM_FORMAT_U16_BE: + case SND_PCM_FORMAT_S16_LE: + case SND_PCM_FORMAT_S16_BE: + pcmSampleSize = 2; + break; + + case SND_PCM_FORMAT_U32_LE: + case SND_PCM_FORMAT_U32_BE: + case SND_PCM_FORMAT_S32_LE: + case SND_PCM_FORMAT_S32_BE: + pcmSampleSize = 4; + break; + + default: + pcmSampleSize = 0; + } + + return pcmSampleSize; +} + +PUBLIC int AlsaPcmConf(CtlSourceT *source, AlsaPcmInfoT *pcm, AlsaPcmHwInfoT *opts) { + char string[32]; + int error; + snd_pcm_hw_params_t *pxmHwParams; + snd_pcm_sw_params_t *pxmSwParams; + + // retrieve hadware config from PCM + snd_pcm_hw_params_alloca(&pxmHwParams); + snd_pcm_hw_params_any(pcm->handle, pxmHwParams); + + if (!opts->access) opts->access = SND_PCM_ACCESS_RW_INTERLEAVED; + error = snd_pcm_hw_params_set_access(pcm->handle, pxmHwParams, opts->access); + if (error) { + AFB_ApiError(source->api, "AlsaPcmConf: Fail PCM=%s Set_Interleave=%d mode error=%s", ALSA_PCM_UID(pcm->handle, string), opts->access, snd_strerror(error)); + goto OnErrorExit; + }; + + if (opts->format != SND_PCM_FORMAT_UNKNOWN) { + if ((error = snd_pcm_hw_params_set_format(pcm->handle, pxmHwParams, opts->format)) < 0) { + AFB_ApiError(source->api, "AlsaPcmConf: Fail PCM=%s Set_Format=%d error=%s", ALSA_PCM_UID(pcm->handle, string), opts->format, snd_strerror(error)); + AlsaDumpFormats(source, pcm->handle); + goto OnErrorExit; + } + } + + if (opts->rate > 0) { + unsigned int pcmRate = opts->rate; + if ((error = snd_pcm_hw_params_set_rate_near(pcm->handle, pxmHwParams, &opts->rate, 0)) < 0) { + AFB_ApiError(source->api, "AlsaPcmConf: Fail PCM=%s Set_Rate=%d error=%s", ALSA_PCM_UID(pcm->handle, string), opts->rate, snd_strerror(error)); + goto OnErrorExit; + } + + // check we got requested rate + if (opts->rate != pcmRate) { + AFB_ApiError(source->api, "AlsaPcmConf: Fail PCM=%s Set_Rate ask=%dHz get=%dHz", ALSA_PCM_UID(pcm->handle, string), pcmRate, opts->rate); + goto OnErrorExit; + } + } + + if (opts->channels) { + if ((error = snd_pcm_hw_params_set_channels(pcm->handle, pxmHwParams, opts->channels)) < 0) { + AFB_ApiError(source->api, "AlsaPcmConf: Fail PCM=%s Set_Channels=%d error=%s", ALSA_PCM_UID(pcm->handle, string), opts->channels, snd_strerror(error)); + goto OnErrorExit; + }; + } + + // store selected values + if ((error = snd_pcm_hw_params(pcm->handle, pxmHwParams)) < 0) { + AFB_ApiError(source->api, "AlsaPcmConf: Fail PCM=%s apply hwparams error=%s", ALSA_PCM_UID(pcm->handle, string), snd_strerror(error)); + goto OnErrorExit; + } + + // check we effective hw params after optional format change + snd_pcm_hw_params_get_channels(pxmHwParams, &opts->channels); + snd_pcm_hw_params_get_format(pxmHwParams, &opts->format); + snd_pcm_hw_params_get_rate(pxmHwParams, &opts->rate, 0); + opts->sampleSize = AlsaPeriodSize(opts->format); + if (opts->sampleSize == 0) { + AFB_ApiError(source->api, "AlsaPcmConf: Fail PCM=%s unsupported format format=%d", ALSA_PCM_UID(pcm->handle, string), opts->format); + goto OnErrorExit; + } + + // retrieve software config from PCM + snd_pcm_sw_params_alloca(&pxmSwParams); + snd_pcm_sw_params_current(pcm->handle, pxmSwParams); + + if ((error = snd_pcm_sw_params_set_avail_min(pcm->handle, pxmSwParams, 16)) < 0) { + AFB_ApiError(source->api, "AlsaPcmConf: Fail to PCM=%s set_buffersize error=%s", ALSA_PCM_UID(pcm->handle, string), snd_strerror(error)); + goto OnErrorExit; + }; + + // push software params into PCM + if ((error = snd_pcm_sw_params(pcm->handle, pxmSwParams)) < 0) { + AFB_ApiError(source->api, "AlsaPcmConf: Fail to push software=%s params error=%s", ALSA_PCM_UID(pcm->handle, string), snd_strerror(error)); + goto OnErrorExit; + }; + + AFB_ApiNotice(source->api, "AlsaPcmConf: PCM=%s channels=%d rate=%d format=%d access=%d done", ALSA_PCM_UID(pcm->handle,string), opts->channels, opts->rate, opts->format, opts->access); + return 0; + +OnErrorExit: + return -1; +} + +STATIC int AlsaPcmReadCB(sd_event_source* src, int fd, uint32_t revents, void* userData) { + char string[32]; + int error; + snd_pcm_sframes_t framesIn, framesOut, availIn, availOut; + AlsaPcmCopyHandleT *pcmCopyHandle = (AlsaPcmCopyHandleT*) userData; + + // PCM has was closed + if ((revents & EPOLLHUP) != 0) { + AFB_ApiNotice(pcmCopyHandle->api, "AlsaPcmReadCB PCM=%s hanghup/disconnected", ALSA_PCM_UID(pcmCopyHandle->pcmIn, string)); + goto ExitOnSuccess; + } + + // ignore any non input events + if ((revents & EPOLLIN) == 0) { + goto ExitOnSuccess; + } + + // retrieve PCM state + snd_pcm_state_t pcmState = snd_pcm_state(pcmCopyHandle->pcmIn); + + // When pause flush remaining frame and wait + if (pcmState == SND_PCM_STATE_PAUSED) { + framesIn = snd_pcm_readi(pcmCopyHandle->pcmIn, pcmCopyHandle->buffer, pcmCopyHandle->frameCount); + AFB_ApiInfo(pcmCopyHandle->api, "AlsaPcmReadCB: paused frame:%ld ignored", framesIn); + goto ExitOnSuccess; + } + + // When XRNS append try to restore PCM + if (pcmState == SND_PCM_STATE_XRUN) { + AFB_ApiNotice(pcmCopyHandle->api, "AlsaPcmReadCB PCM=%s XRUN", ALSA_PCM_UID(pcmCopyHandle->pcmIn, string)); + snd_pcm_prepare(pcmCopyHandle->pcmIn); + } + + // when PCM suspending loop until ready to go + if (pcmState == SND_PCM_STATE_SUSPENDED) { + while (1) { + if ((error = snd_pcm_resume(pcmCopyHandle->pcmIn)) < 0) { + AFB_ApiNotice(pcmCopyHandle->api, "AlsaPcmReadCB PCM=%s SUSPENDED fail to resume", ALSA_PCM_UID(pcmCopyHandle->pcmIn, string)); + sleep(1); // Fulup should be replace with corresponding AFB_timer + } else { + AFB_ApiNotice(pcmCopyHandle->api, "AlsaPcmReadCB PCM=%s SUSPENDED success to resume", ALSA_PCM_UID(pcmCopyHandle->pcmIn, string)); + } + } + } + + // do we have waiting frame + availIn = snd_pcm_avail_update(pcmCopyHandle->pcmIn); + if (availIn <= 0) { + goto ExitOnSuccess; + } + + // do we have space to push frame + availOut = snd_pcm_avail_update(pcmCopyHandle->pcmOut); + if (availOut <= 0) { + snd_pcm_prepare(pcmCopyHandle->pcmOut); + goto ExitOnSuccess; + } + + // make sure we can push all input frame into output pcm without locking + if (availOut < availIn) availIn = availOut; + + // we get too many data ignore some + if (availIn > pcmCopyHandle->frameCount) { + availIn = pcmCopyHandle->frameCount; + } + + // effectively read pcmIn and push frame to pcmOut + framesIn = snd_pcm_readi(pcmCopyHandle->pcmIn, pcmCopyHandle->buffer, availIn); + if (framesIn < 0 || framesIn != availIn) { + AFB_ApiNotice(pcmCopyHandle->api, "AlsaPcmReadCB PcmIn=%s UNDERUN frame=%ld", ALSA_PCM_UID(pcmCopyHandle->pcmIn, string), framesIn); + goto ExitOnSuccess; + } + + // In/Out frames transfer through buffer copy + framesOut = snd_pcm_writei(pcmCopyHandle->pcmOut, pcmCopyHandle->buffer, framesIn); + if (framesOut < 0 || framesOut != framesIn) { + AFB_ApiNotice(pcmCopyHandle->api, "AlsaPcmReadCB PcmOut=%s UNDERUN/SUSPEND frameOut=%ld", ALSA_PCM_UID(pcmCopyHandle->pcmOut, string), framesOut); + goto ExitOnSuccess; + } + + if (framesIn != framesOut) { + AFB_ApiNotice(pcmCopyHandle->api, "AlsaPcmReadCB PCM=%s Loosing frames=%ld", ALSA_PCM_UID(pcmCopyHandle->pcmOut, string), (framesIn - framesOut)); + goto ExitOnSuccess; + } + + return 0; + + // Cannot handle error in callback +ExitOnSuccess: + return 0; +} + +static void *LoopInThread(void *handle) { + AlsaPcmCopyHandleT *pcmCopyHandle = (AlsaPcmCopyHandleT*) handle; + int count = 0; + int watchdog = MAINLOOP_WATCHDOG * 1000; + pcmCopyHandle->tid = (int) syscall(SYS_gettid); + + AFB_ApiNotice(pcmCopyHandle->api, "LoopInThread:%s/%d Started", pcmCopyHandle->info, pcmCopyHandle->tid); + + + /* loop until end */ + for (;;) { + int res = sd_event_run(pcmCopyHandle->sdLoop, watchdog); + if (res == 0) { + AFB_ApiInfo(pcmCopyHandle->api, "LoopInThread:%s/%d Idle count=%d", pcmCopyHandle->info, pcmCopyHandle->tid, count++); + continue; + } + if (res < 0) { + AFB_ApiError(pcmCopyHandle->api, "LoopInThread:%s/%d ERROR=%i Exit errno=%s.\n", pcmCopyHandle->info, pcmCopyHandle->tid, res, strerror(res)); + break; + } + } + pthread_exit(0); +} + +PUBLIC int AlsaPcmCopy(CtlSourceT *source, AlsaPcmInfoT *pcmIn, AlsaPcmInfoT *pcmOut, AlsaPcmHwInfoT * opts) { + char string[32]; + struct pollfd *pcmInFds; + int error; + + // prepare PCM for capture and replay + error = AlsaPcmConf(source, pcmIn, opts); + if (error) goto OnErrorExit; + + // Prepare PCM for usage + if ((error = snd_pcm_start(pcmIn->handle)) < 0) { + AFB_ApiError(source->api, "AlsaPcmCopy: Fail to prepare PCM=%s error=%s", ALSA_PCM_UID(pcmIn->handle, string), snd_strerror(error)); + goto OnErrorExit; + }; + + + error = AlsaPcmConf(source, pcmOut, opts); + if (error) goto OnErrorExit; + + // Prepare PCM for usage + if ((error = snd_pcm_prepare(pcmOut->handle)) < 0) { + AFB_ApiError(source->api, "AlsaPcmCopy: Fail to start PCM=%s error=%s", ALSA_PCM_UID(pcmOut->handle, string), snd_strerror(error)); + goto OnErrorExit; + }; + + + + AlsaPcmCopyHandleT *pcmCopyHandle = malloc(sizeof (AlsaPcmCopyHandleT)); + pcmCopyHandle->info = "pcmCpy"; + pcmCopyHandle->pcmIn = pcmIn->handle; + pcmCopyHandle->pcmOut = pcmOut->handle; + pcmCopyHandle->api = source->api; + pcmCopyHandle->channels = opts->channels; + pcmCopyHandle->frameSize = opts->channels * opts->sampleSize; + pcmCopyHandle->frameCount = BUFFER_FRAME_COUNT; + pcmCopyHandle->buffer = malloc(pcmCopyHandle->frameCount * pcmCopyHandle->frameSize); + + // get FD poll descriptor for capture PCM + int pcmInCount = snd_pcm_poll_descriptors_count(pcmCopyHandle->pcmIn); + if (pcmInCount <= 0) { + AFB_ApiError(source->api, "AlsaPcmCopy: Fail pcmIn=%s get fds count error=%s", ALSA_PCM_UID(pcmIn->handle, string), snd_strerror(error)); + goto OnErrorExit; + }; + + pcmInFds = alloca(sizeof (*pcmInFds) * pcmInCount); + if ((error = snd_pcm_poll_descriptors(pcmIn->handle, pcmInFds, pcmInCount)) < 0) { + AFB_ApiError(source->api, "AlsaPcmCopy: Fail pcmIn=%s get pollfds error=%s", ALSA_PCM_UID(pcmOut->handle, string), snd_strerror(error)); + goto OnErrorExit; + }; + + // add poll descriptor to AGL systemd mainloop + if ((error = sd_event_new(&pcmCopyHandle->sdLoop)) < 0) { + fprintf(stderr, "LaunchCallRequest: fail pcmin=%s creating a new loop: %s\n", ALSA_PCM_UID(pcmOut->handle, string), strerror(error)); + goto OnErrorExit; + } + + for (int idx = 0; idx < pcmInCount; idx++) { + if ((error = sd_event_add_io(pcmCopyHandle->sdLoop, &pcmCopyHandle->evtsrc, pcmInFds[idx].fd, EPOLLIN, AlsaPcmReadCB, pcmCopyHandle)) < 0) { + AFB_ApiError(source->api, "AlsaPcmCopy: Fail pcmIn=%s sd_event_add_io err=%d", ALSA_PCM_UID(pcmIn->handle, string), error); + goto OnErrorExit; + } + } + + // start a thread with a mainloop to monitor Audio-Agent + if ((error = pthread_create(&pcmCopyHandle->thread, NULL, &LoopInThread, pcmCopyHandle)) < 0) { + AFB_ApiError(source->api, "AlsaPcmCopy: Fail create waiting thread pcmIn=%s err=%d", ALSA_PCM_UID(pcmIn->handle, string), error); + goto OnErrorExit; + } + + return 0; + +OnErrorExit: + AFB_ApiError(source->api, "AlsaPcmCopy: Fail \n - pcmIn=%s \n - pcmOut=%s", ALSA_PCM_UID(pcmIn->handle, string), ALSA_PCM_UID(pcmOut->handle, string)); + + return -1; +} + |