| /* Process Queue: ALSA PCM output */ |
| /* (C) 2017 by Harald Welte <laforge@gnumonks.org> */ |
| |
| /* |
| * This file is part of gapk (GSM Audio Pocket Knife). |
| * |
| * gapk is free software: you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation, either version 3 of the License, or |
| * (at your option) any later version. |
| * |
| * gapk is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with gapk. If not, see <http://www.gnu.org/licenses/>. |
| */ |
| |
| #include <errno.h> |
| #include <stdint.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| |
| #include <gapk/codecs.h> |
| #include <gapk/formats.h> |
| #include <gapk/procqueue.h> |
| |
| #include "config.h" |
| |
| #ifdef HAVE_ALSA |
| |
| #include <alsa/asoundlib.h> |
| |
| |
| struct pq_state_alsa { |
| snd_pcm_t *pcm_handle; |
| unsigned int blk_len; |
| }; |
| |
| static int |
| pq_cb_alsa_input(void *_state, uint8_t *out, const uint8_t *in, unsigned int in_len) |
| { |
| struct pq_state_alsa *state = _state; |
| unsigned int num_samples = state->blk_len/2; |
| int rv; |
| rv = snd_pcm_readi(state->pcm_handle, out, num_samples); |
| if (rv < 0) |
| return rv; |
| return rv * sizeof(uint16_t); |
| } |
| |
| static int |
| pq_cb_alsa_output(void *_state, uint8_t *out, const uint8_t *in, unsigned int in_len) |
| { |
| struct pq_state_alsa *state = _state; |
| unsigned int num_samples = in_len/2; |
| int rv; |
| rv = snd_pcm_writei(state->pcm_handle, in, num_samples); |
| return rv == num_samples ? 0 : -1; |
| } |
| |
| static void |
| pq_cb_alsa_exit(void *_state) |
| { |
| struct pq_state_alsa *state = _state; |
| snd_pcm_close(state->pcm_handle); |
| } |
| |
| static int |
| pq_queue_alsa_op(struct pq *pq, const char *alsa_dev, unsigned int blk_len, int in_out_n) |
| { |
| struct pq_item *item; |
| struct pq_state_alsa *state; |
| snd_pcm_hw_params_t *hw_params; |
| int rc = -1; |
| |
| state = calloc(1, sizeof(struct pq_state_alsa)); |
| if (!state) |
| return -ENOMEM; |
| |
| rc = snd_pcm_open(&state->pcm_handle, alsa_dev, |
| in_out_n ? SND_PCM_STREAM_CAPTURE : SND_PCM_STREAM_PLAYBACK, 0); |
| if (rc < 0) |
| return rc; |
| state->blk_len = blk_len; |
| |
| rc = snd_pcm_hw_params_malloc(&hw_params); |
| if (rc < 0) |
| goto out_close; |
| |
| rc = snd_pcm_hw_params_any(state->pcm_handle, hw_params); |
| if (rc < 0) |
| goto out_free_par; |
| |
| rc = snd_pcm_hw_params_set_access(state->pcm_handle, hw_params, SND_PCM_ACCESS_RW_INTERLEAVED); |
| if (rc < 0) |
| goto out_free_par; |
| |
| rc = snd_pcm_hw_params_set_format(state->pcm_handle, hw_params, SND_PCM_FORMAT_S16_LE); |
| if (rc < 0) |
| goto out_free_par; |
| |
| rc = snd_pcm_hw_params_set_rate(state->pcm_handle, hw_params, 8000, 0); |
| if (rc < 0) |
| goto out_free_par; |
| |
| rc = snd_pcm_hw_params_set_channels (state->pcm_handle, hw_params, 1); |
| if (rc < 0) |
| goto out_free_par; |
| |
| rc = snd_pcm_hw_params(state->pcm_handle, hw_params); |
| if (rc < 0) |
| goto out_free_par; |
| |
| snd_pcm_hw_params_free(hw_params); |
| |
| item = pq_add_item(pq); |
| if (!item) { |
| rc = -ENOMEM; |
| goto out_close; |
| } |
| |
| item->len_in = in_out_n ? 0 : blk_len; |
| item->len_out = in_out_n ? blk_len : 0; |
| item->state = state; |
| item->proc = in_out_n ? pq_cb_alsa_input : pq_cb_alsa_output; |
| item->exit = pq_cb_alsa_exit; |
| |
| return 0; |
| |
| out_free_par: |
| snd_pcm_hw_params_free(hw_params); |
| out_close: |
| snd_pcm_close(state->pcm_handle); |
| free(state); |
| return rc; |
| } |
| |
| |
| /*! Add ALSA input to given processing queue |
| * This usually only makes sense as first item in the queue |
| * \param pq Processing Queue to add the ALSA input to |
| * \param[in] hwdev ALSA hardware device to use |
| * \param[in] blk_len block length to be read from device |
| * \returns 0 on sucess; negative on error */ |
| int |
| pq_queue_alsa_input(struct pq *pq, const char *hwdev, unsigned int blk_len) |
| { |
| return pq_queue_alsa_op(pq, hwdev, blk_len, 1); |
| } |
| |
| /*! Add ALSA output to given processing queue |
| * This usually only makes sense as first item in the queue |
| * \param pq Processing Queue to add the ALSA output to |
| * \param[in] hwdev ALSA hardware device to use |
| * \param[in] blk_len block length to be written to device |
| * \returns 0 on sucess; negative on error */ |
| int |
| pq_queue_alsa_output(struct pq *pq, const char *hwdev, unsigned int blk_len) |
| { |
| return pq_queue_alsa_op(pq, hwdev, blk_len, 0); |
| } |
| |
| #endif /* HAVE_ALSA */ |