HelenOS sources

root/uspace/app/wavplay/dplay.c

DEFINITIONS

1. playback_initialize
2. device_event_callback
3. play_fragment
4. buffer_occupied
5. buffer_avail
6. buffer_remain
7. buffer_advance
8. play
9. dplay

/*
 * Copyright (c) 2012 Jan Vesely
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/** @addtogroup wavplay
 * @{
 */
/**
 * @file PCM playback audio devices
 */

#include <assert.h>
#include <errno.h>
#include <str_error.h>
#include <str.h>
#include <audio_pcm_iface.h>
#include <fibril_synch.h>
#include <pcm/format.h>
#include <as.h>
#include <time.h>
#include <inttypes.h>
#include <stdbool.h>
#include <stdio.h>
#include <macros.h>

#include "wave.h"
#include "dplay.h"

#define DEFAULT_FRAGMENTS 2

/** Playback helper structure */
typedef struct {
        struct {
                void *base;
                size_t size;
                void *write_ptr;
        } buffer;
        pcm_format_t f;
        FILE *source;
        volatile bool playing;
        fibril_mutex_t mutex;
        fibril_condvar_t cv;
        audio_pcm_sess_t *device;
} playback_t;

/**
 * Initialize playback helper structure.
 * @param pb Pointer to helper structure to initialize
 * @param sess Pointer to audio device IPC session
 * @return
 */
static void playback_initialize(playback_t *pb, audio_pcm_sess_t *sess)
{
        assert(sess);
        assert(pb);
        pb->buffer.base = NULL;
        pb->buffer.size = 0;
        pb->buffer.write_ptr = NULL;
        pb->playing = false;
        pb->source = NULL;
        pb->device = sess;
        fibril_mutex_initialize(&pb->mutex);
        fibril_condvar_initialize(&pb->cv);
}

/** Fragment playback callback function.
 *
 * @param icall Pointer to the call structure
 * @param arg   Argument, pointer to the playback helper function
 *
 */
static void device_event_callback(ipc_call_t *icall, void *arg)
{
        playback_t *pb = arg;
        const size_t fragment_size = pb->buffer.size / DEFAULT_FRAGMENTS;

        while (true) {
                ipc_call_t call;
                async_get_call(&call);

                switch (ipc_get_imethod(&call)) {
                case PCM_EVENT_PLAYBACK_STARTED:
                case PCM_EVENT_FRAMES_PLAYED:
                        printf("%" PRIun " frames: ", ipc_get_arg1(&call));
                        async_answer_0(&call, EOK);
                        break;
                case PCM_EVENT_PLAYBACK_TERMINATED:
                        printf("Playback terminated\n");
                        fibril_mutex_lock(&pb->mutex);
                        pb->playing = false;
                        fibril_condvar_signal(&pb->cv);
                        async_answer_0(&call, EOK);
                        fibril_mutex_unlock(&pb->mutex);
                        return;
                default:
                        printf("Unknown event %" PRIun ".\n", ipc_get_imethod(&call));
                        async_answer_0(&call, ENOTSUP);
                        continue;

                }
                const size_t bytes = fread(pb->buffer.write_ptr,
                    sizeof(uint8_t), fragment_size, pb->source);
                printf("Copied from position %p size %zu/%zu\n",
                    pb->buffer.write_ptr, bytes, fragment_size);
                if (bytes == 0) {
                        audio_pcm_last_playback_fragment(pb->device);
                }
                /* any constant is silence */
                memset(pb->buffer.write_ptr + bytes, 0, fragment_size - bytes);
                pb->buffer.write_ptr += fragment_size;

                if (pb->buffer.write_ptr >= (pb->buffer.base + pb->buffer.size))
                        pb->buffer.write_ptr -= pb->buffer.size;
        }
}

/**
 * Start event based playback.
 * @param pb Playback helper structure.
 */
static void play_fragment(playback_t *pb)
{
        assert(pb);
        assert(pb->device);
        const size_t fragment_size = pb->buffer.size / DEFAULT_FRAGMENTS;
        printf("Registering event callback\n");
        errno_t ret = audio_pcm_register_event_callback(pb->device,
            device_event_callback, pb);
        if (ret != EOK) {
                printf("Failed to register event callback: %s.\n",
                    str_error(ret));
                return;
        }
        printf("Playing: %dHz, %s, %d channel(s).\n", pb->f.sampling_rate,
            pcm_sample_format_str(pb->f.sample_format), pb->f.channels);
        const size_t bytes = fread(pb->buffer.base, sizeof(uint8_t),
            fragment_size, pb->source);
        if (bytes != fragment_size)
                memset(pb->buffer.base + bytes, 0, fragment_size - bytes);
        printf("Initial: Copied from position %p size %zu/%zu\n",
            pb->buffer.base, bytes, fragment_size);
        pb->buffer.write_ptr = pb->buffer.base + fragment_size;
        fibril_mutex_lock(&pb->mutex);
        const unsigned frames =
            pcm_format_size_to_frames(fragment_size, &pb->f);
        ret = audio_pcm_start_playback_fragment(pb->device, frames,
            pb->f.channels, pb->f.sampling_rate, pb->f.sample_format);
        if (ret != EOK) {
                fibril_mutex_unlock(&pb->mutex);
                printf("Failed to start playback: %s.\n", str_error(ret));
                audio_pcm_unregister_event_callback(pb->device);
                return;
        }

        pb->playing = true;
        while (pb->playing)
                fibril_condvar_wait(&pb->cv, &pb->mutex);

        fibril_mutex_unlock(&pb->mutex);
        printf("\n");
        audio_pcm_unregister_event_callback(pb->device);
}

/**
 * Count occupied space in a cyclic buffer.
 * @param pb Playback helper structure.
 * @param pos read pointer position.
 * @return Occupied space size.
 */
static size_t buffer_occupied(const playback_t *pb, size_t pos)
{
        assert(pb);
        void *read_ptr = pb->buffer.base + pos;
        if (read_ptr > pb->buffer.write_ptr)
                return pb->buffer.write_ptr + pb->buffer.size - read_ptr;
        return pb->buffer.write_ptr - read_ptr;

}

/**
 * Count available space in a cyclic buffer.
 * @param pb Playback helper structure.
 * @param pos read pointer position.
 * @return Free space size.
 */
static size_t buffer_avail(const playback_t *pb, size_t pos)
{
        assert(pb);
        void *read_ptr = pb->buffer.base + pos;
        if (read_ptr <= pb->buffer.write_ptr)
                return read_ptr + pb->buffer.size - pb->buffer.write_ptr - 1;
        return (read_ptr - pb->buffer.write_ptr) - 1;
}

/**
 * Size of the space between write pointer and the end of a cyclic buffer
 * @param pb Playback helper structure.
 */
static size_t buffer_remain(const playback_t *pb)
{
        assert(pb);
        return (pb->buffer.base + pb->buffer.size) - pb->buffer.write_ptr;
}

/**
 * Move write pointer forward. Wrap around the end.
 * @param pb Playback helper structure.
 * @param bytes NUmber of bytes to advance.
 */
static void buffer_advance(playback_t *pb, size_t bytes)
{
        assert(pb);
        pb->buffer.write_ptr += bytes;
        while (pb->buffer.write_ptr >= (pb->buffer.base + pb->buffer.size))
                pb->buffer.write_ptr -= pb->buffer.size;
}

#define DPRINTF(f, ...) \
        printf("%.2lld:%.6lld   "f, time.tv_sec % 100, \
            NSEC2USEC(time.tv_nsec), __VA_ARGS__)

/**
 * Start playback using buffer position api.
 * @param pb Playback helper function.
 */
static void play(playback_t *pb)
{
        assert(pb);
        assert(pb->device);
        pb->buffer.write_ptr = pb->buffer.base;
        printf("Playing: %dHz, %s, %d channel(s).\n", pb->f.sampling_rate,
            pcm_sample_format_str(pb->f.sample_format), pb->f.channels);
        usec_t work_time = 50000; /* 50 ms */
        bool started = false;
        size_t pos = 0;
        struct timespec time = { 0 };
        getuptime(&time);
        while (true) {
                size_t available = buffer_avail(pb, pos);
                /*
                 * Writing might need wrap around the end,
                 * read directly to device buffer
                 */
                size_t bytes = fread(pb->buffer.write_ptr, sizeof(uint8_t),
                    min(available, buffer_remain(pb)), pb->source);
                buffer_advance(pb, bytes);
                DPRINTF("POS %zu: %zu bytes free in buffer, read %zu, wp %zu\n",
                    pos, available, bytes,
                    pb->buffer.write_ptr - pb->buffer.base);
                available -= bytes;

                /* continue if we wrapped around the end */
                if (available) {
                        bytes = fread(pb->buffer.write_ptr,
                            sizeof(uint8_t), min(available, buffer_remain(pb)),
                            pb->source);
                        buffer_advance(pb, bytes);
                        DPRINTF("POS %zu: %zu bytes still free in buffer, "
                            "read %zu, wp %zu\n", pos, available, bytes,
                            pb->buffer.write_ptr - pb->buffer.base);
                        available -= bytes;
                }

                if (!started) {
                        errno_t ret = audio_pcm_start_playback(pb->device,
                            pb->f.channels, pb->f.sampling_rate,
                            pb->f.sample_format);
                        if (ret != EOK) {
                                printf("Failed to start playback: %s\n",
                                    str_error(ret));
                                return;
                        }
                        started = true;
                        ret = audio_pcm_get_buffer_pos(pb->device, &pos);
                        if (ret != EOK) {
                                printf("Failed to update position indicator "
                                    "%s\n", str_error(ret));
                        }
                }
                const size_t to_play = buffer_occupied(pb, pos);
                const usec_t usecs = pcm_format_size_to_usec(to_play, &pb->f);

                /* Compute delay time */
                const usec_t real_delay = (usecs > work_time) ?
                    usecs - work_time : 0;
                DPRINTF("POS %zu: %lld usecs (%lld) to play %zu bytes.\n",
                    pos, usecs, real_delay, to_play);
                if (real_delay)
                        fibril_usleep(real_delay);
                /* update buffer position */
                const errno_t ret = audio_pcm_get_buffer_pos(pb->device, &pos);
                if (ret != EOK) {
                        printf("Failed to update position indicator %s\n",
                            str_error(ret));
                }
                getuptime(&time);

                /*
                 * we did not use all the space we had,
                 * that is the end
                 */
                if (available)
                        break;

        }
        audio_pcm_stop_playback_immediate(pb->device);
}

/**
 * Play audio file usign direct device access.
 * @param device The device.
 * @param file The file.
 * @return 0 on success, non-zero on failure.
 */
int dplay(const char *device, const char *file)
{
        errno_t ret = EOK;
        audio_pcm_sess_t *session = NULL;
        if (str_cmp(device, "default") == 0) {
                session = audio_pcm_open_default();
        } else {
                session = audio_pcm_open(device);
        }
        if (!session) {
                printf("Failed to connect to device %s.\n", device);
                return 1;
        }
        printf("Playing on device: %s.\n", device);
        sysarg_t val;
        ret = audio_pcm_query_cap(session, AUDIO_CAP_PLAYBACK, &val);
        if (ret != EOK || !val) {
                printf("Device %s does not support playback\n", device);
                ret = ENOTSUP;
                goto close_session;
        }

        char *info = NULL;
        ret = audio_pcm_get_info_str(session, &info);
        if (ret != EOK) {
                printf("Failed to get PCM info: %s.\n", str_error(ret));
                goto close_session;
        }
        printf("Playing on %s.\n", info);
        free(info);

        playback_t pb;
        playback_initialize(&pb, session);

        ret = audio_pcm_get_buffer(pb.device, &pb.buffer.base, &pb.buffer.size);
        if (ret != EOK) {
                printf("Failed to get PCM buffer: %s.\n", str_error(ret));
                goto close_session;
        }
        printf("Buffer: %p %zu.\n", pb.buffer.base, pb.buffer.size);

        pb.source = fopen(file, "rb");
        if (pb.source == NULL) {
                ret = ENOENT;
                printf("Failed to open file: %s.\n", file);
                goto cleanup;
        }

        wave_header_t header;
        fread(&header, sizeof(header), 1, pb.source);
        const char *error;
        ret = wav_parse_header(&header, NULL, NULL,
            &pb.f.channels, &pb.f.sampling_rate, &pb.f.sample_format, &error);
        if (ret != EOK) {
                printf("Error parsing wav header: %s.\n", error);
                goto cleanup;
        }
        ret = audio_pcm_query_cap(pb.device, AUDIO_CAP_BUFFER_POS, &val);
        if (ret == EOK && val) {
                play(&pb);
        } else {
                ret = audio_pcm_query_cap(pb.device, AUDIO_CAP_INTERRUPT, &val);
                if (ret == EOK && val)
                        play_fragment(&pb);
                else
                        printf("Neither playing method is supported");
        }

cleanup:
        fclose(pb.source);
        as_area_destroy(pb.buffer.base);
        audio_pcm_release_buffer(pb.device);
close_session:
        audio_pcm_close(session);
        return ret == EOK ? 0 : 1;
}
/**
 * @}
 */