source: mainline/uspace/app/wavplay/wave.c

/*
 * Copyright (c) 2011 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 <byteorder.h>
#include <str.h>
#include <errno.h>

#include "wave.h"

/**
 * Parse wav header data.
 * @param[in] hdata Header data to parse.
 * @param[out] data Pointer to audio data.
 * @param[out] data_size Size of the data after the header.
 * @param[out] channels Number of channels in stored audio format.
 * @param[out] sampling_rate Sampling rate of the store data.
 * @param[out] format Sample format.
 * @param[out] error String representatoin of error, if any.
 * @return Error code.
 *
 * Does sanity checks and endian conversion.
 */
errno_t wav_parse_header(const void *hdata, const void **data, size_t *data_size,
    unsigned *channels, unsigned *sampling_rate, pcm_sample_format_t *format,
    const char **error)
{
        if (!hdata) {
                if (error)
                        *error = "no header";
                return EINVAL;
        }

        const wave_header_t *header = hdata;
        if (str_lcmp(header->chunk_id, CHUNK_ID, 4) != 0) {
                if (error)
                        *error = "invalid chunk id";
                return EINVAL;
        }

        if (str_lcmp(header->format, FORMAT_STR, 4) != 0) {
                if (error)
                        *error = "invalid format string";
                return EINVAL;
        }

        if (str_lcmp(header->subchunk1_id, SUBCHUNK1_ID, 4) != 0) {
                if (error)
                        *error = "invalid subchunk1 id";
                return EINVAL;
        }

        if (uint32_t_le2host(header->subchunk1_size) != PCM_SUBCHUNK1_SIZE) {
                //TODO subchunk 1 sizes other than 16 are allowed ( 18, 40)
                //http://www-mmsp.ece.mcgill.ca/documents/AudioFormats/WAVE/WAVE.html
                if (error)
                        *error = "invalid subchunk1 size";
                return EINVAL;
        }

        if (uint16_t_le2host(header->audio_format) != FORMAT_LINEAR_PCM) {
                if (error)
                        *error = "unknown format";
                return ENOTSUP;
        }

        if (str_lcmp(header->subchunk2_id, SUBCHUNK2_ID, 4) != 0) {
                //TODO basedd on subchunk1 size, we might be reading wrong
                //offset
                if (error)
                        *error = "invalid subchunk2 id";
                return EINVAL;
        }

        //TODO data and data_size are incorrect in extended wav formats
        //pcm params are OK
        if (data)
                *data = header->data;
        if (data_size)
                *data_size = uint32_t_le2host(header->subchunk2_size);

        if (sampling_rate)
                *sampling_rate = uint32_t_le2host(header->sampling_rate);
        if (channels)
                *channels = uint16_t_le2host(header->channels);
        if (format) {
                const unsigned size = uint16_t_le2host(header->sample_size);
                switch (size) {
                case 8:
                        *format = PCM_SAMPLE_UINT8;
                        break;
                case 16:
                        *format = PCM_SAMPLE_SINT16_LE;
                        break;
                case 24:
                        *format = PCM_SAMPLE_SINT24_LE;
                        break;
                case 32:
                        *format = PCM_SAMPLE_SINT32_LE;
                        break;
                default:
                        *error = "Unknown format";
                        return ENOTSUP;
                }
        }
        if (error)
                *error = "no error";

        return EOK;
}

/**
 * Initialize wave fromat ehader structure.
 * @param header Structure to initialize.
 * @param format Desired PCM format
 * @param size Size of the stored data.
 *
 * Initializes format specific elements and covnerts endian
 */
void wav_init_header(wave_header_t *header, pcm_format_t format, size_t size)
{
        assert(header);
#define COPY_STR(dst, src)   memcpy(dst, src, str_size(src))

        COPY_STR(&header->chunk_id, CHUNK_ID);
        COPY_STR(&header->format, FORMAT_STR);
        COPY_STR(&header->subchunk1_id, SUBCHUNK1_ID);
        header->subchunk1_size = host2uint16_t_le(PCM_SUBCHUNK1_SIZE);
        header->audio_format = host2uint16_t_le(FORMAT_LINEAR_PCM);

        COPY_STR(&header->subchunk2_id, SUBCHUNK2_ID);
        header->subchunk2_size = host2uint32_t_le(size);
        header->sampling_rate = host2uint32_t_le(format.sampling_rate);
        header->channels = host2uint32_t_le(format.channels);
        header->sample_size =
            host2uint16_t_le(pcm_sample_format_size(format.sample_format) * 8);
}
/**
 * @}
 */