/* * lingot, a musical instrument tuner. * * Copyright (C) 2004-2011 Ibán Cereijo Graña, Jairo Chapela Martínez. * * This file is part of lingot. * * lingot 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 2 of the License, or * (at your option) any later version. * * lingot 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 lingot; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ #include <stdlib.h> #include "lingot-defs.h" #include "lingot-audio-alsa.h" #include "lingot-i18n.h" #include "lingot-msg.h" LingotAudioHandler* lingot_audio_alsa_new(char* device, int sample_rate) { LingotAudioHandler* audio = NULL; # ifdef ALSA const char* exception; snd_pcm_hw_params_t* hw_params = NULL; int err; char error_message[1000]; unsigned int channels = 1; audio = malloc(sizeof(LingotAudioHandler)); audio->read_buffer = NULL; audio->audio_system = AUDIO_SYSTEM_ALSA; audio->read_buffer_size = 128; // TODO: size up // ALSA allocates some mem to load its config file when we call // snd_card_next. Now that we're done getting the info, let's tell ALSA // to unload the info and free up that mem snd_config_update_free_global(); audio->capture_handle = NULL; try { if ((err = snd_pcm_open(&audio->capture_handle, device, SND_PCM_STREAM_CAPTURE, 0)) < 0) { sprintf(error_message, "Cannot open audio device %s.\n%s.", device, snd_strerror(err)); throw(error_message); } strcpy(audio->device, device); if ((err = snd_pcm_hw_params_malloc(&hw_params)) < 0) { sprintf(error_message, "Cannot allocate hardware parameter structure.\n%s.", snd_strerror(err)); throw(error_message); } if ((err = snd_pcm_hw_params_any(audio->capture_handle, hw_params)) < 0) { sprintf(error_message, "Cannot initialize hardware parameter structure.\n%s.", snd_strerror(err)); throw(error_message); } if ((err = snd_pcm_hw_params_set_access(audio->capture_handle, hw_params, SND_PCM_ACCESS_RW_INTERLEAVED)) < 0) { sprintf(error_message, "Cannot set access type.\n%s", snd_strerror( err)); throw(error_message); } if ((err = snd_pcm_hw_params_set_format(audio->capture_handle, hw_params, SND_PCM_FORMAT_S16_LE)) < 0) { sprintf(error_message, "Cannot set sample format.\n%s.", snd_strerror(err)); throw(error_message); } unsigned int rate = sample_rate; if ((err = snd_pcm_hw_params_set_rate_near(audio->capture_handle, hw_params, &rate, 0)) < 0) { sprintf(error_message, "Cannot set sample rate.\n%s.", snd_strerror(err)); throw(error_message); } audio->real_sample_rate = rate; if ((err = snd_pcm_hw_params_set_channels(audio->capture_handle, hw_params, channels)) < 0) { sprintf(error_message, "Cannot set channel count.\n%s.", snd_strerror(err)); throw(error_message); } if ((err = snd_pcm_hw_params(audio->capture_handle, hw_params)) < 0) { sprintf(error_message, "Cannot set parameters.\n%s.", snd_strerror( err)); throw(error_message); } if ((err = snd_pcm_prepare(audio->capture_handle)) < 0) { sprintf(error_message, "Cannot prepare audio interface for use.\n%s.", snd_strerror(err)); throw(error_message); } audio->read_buffer = malloc(channels * audio->read_buffer_size * sizeof(SAMPLE_TYPE)); memset(audio->read_buffer, 0, audio->read_buffer_size * sizeof(SAMPLE_TYPE)); } catch { if (audio->capture_handle != NULL) snd_pcm_close(audio->capture_handle); free(audio); audio = NULL; lingot_msg_add_error(exception); } if (hw_params != NULL) snd_pcm_hw_params_free(hw_params); # else lingot_msg_add_error( _("The application has not been built with ALSA support")); # endif return audio; } void lingot_audio_alsa_destroy(LingotAudioHandler* audio) { # ifdef ALSA if (audio != NULL) { snd_pcm_close(audio->capture_handle); free(audio->read_buffer); } # endif } int lingot_audio_alsa_read(LingotAudioHandler* audio) { # ifdef ALSA int temp_sret; int i; temp_sret = snd_pcm_readi(audio->capture_handle, audio->read_buffer, audio->read_buffer_size); // if (rand() < 0.001 * RAND_MAX) // temp_sret = 0; if (temp_sret != audio->read_buffer_size) { char buff[100]; sprintf(buff, _("Read from audio interface failed.\n%s."), snd_strerror(temp_sret)); lingot_msg_add_error(buff); return -1; } // float point conversion for (i = 0; i < audio->read_buffer_size; i++) { audio->flt_read_buffer[i] = audio->read_buffer[i]; } # endif return 0; } LingotAudioSystemProperties* lingot_audio_alsa_get_audio_system_properties( audio_system_t audio_system) { LingotAudioSystemProperties* result = (LingotAudioSystemProperties*) malloc(1 * sizeof(LingotAudioSystemProperties)); // TODO result->forced_sample_rate = 0; result->n_devices = 0; result->devices = NULL; result->n_sample_rates = 5; result->sample_rates = malloc(result->n_sample_rates * sizeof(int)); result->sample_rates[0] = 8000; result->sample_rates[1] = 11025; result->sample_rates[2] = 22050; result->sample_rates[3] = 44100; result->sample_rates[4] = 48000; return result; }