guacamole-spice-protocol/src/libguac/audio.c

/* ***** BEGIN LICENSE BLOCK *****
 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (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.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is libguac.
 *
 * The Initial Developer of the Original Code is
 * Michael Jumper.
 * Portions created by the Initial Developer are Copyright (C) 2010
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either the GNU General Public License Version 2 or later (the "GPL"), or
 * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
 * of those above. If you wish to allow use of your version of this file only
 * under the terms of either the GPL or the LGPL, and not to allow others to
 * use your version of this file under the terms of the MPL, indicate your
 * decision by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL or the LGPL. If you do not delete
 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the MPL, the GPL or the LGPL.
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 * ***** END LICENSE BLOCK ***** */

#include <stdlib.h>
#include <string.h>
#include <pthread.h>
#include <guacamole/protocol.h>
#include <guacamole/client.h>
#include <guacamole/stream.h>
#include <guacamole/audio.h>

#ifdef ENABLE_OGG
#include "ogg_encoder.h"
#endif

#include "wav_encoder.h"

guac_audio_stream* guac_audio_stream_alloc(guac_client* client, guac_audio_encoder* encoder) {

    guac_audio_stream* audio;

    /* Choose an encoding if not specified */
    if (encoder == NULL) {

        int i;

        /* For each supported mimetype, check for an associated encoder */
        for (i=0; client->info.audio_mimetypes[i] != NULL; i++) {

            const char* mimetype = client->info.audio_mimetypes[i];

#ifdef ENABLE_OGG
            /* If Ogg is supported, done. */
            if (strcmp(mimetype, ogg_encoder->mimetype) == 0) {
                encoder = ogg_encoder;
                break;
            }
#endif

            /* If wav is supported, done. */
            if (strcmp(mimetype, wav_encoder->mimetype) == 0) {
                encoder = wav_encoder;
                break;
            }

        } /* end for each mimetype */

        /* If still no encoder could be found, fail */
        if (encoder == NULL)
            return NULL;

    }

    /* Allocate stream */
    audio = (guac_audio_stream*) malloc(sizeof(guac_audio_stream));
    audio->client = client;

    /* Reset buffer stats */
    audio->used = 0;
    audio->length = 0x40000;

    audio->encoded_data_used = 0;
    audio->encoded_data_length = 0x40000;

    /* Allocate buffers */
    audio->pcm_data = malloc(audio->length);
    audio->encoded_data = malloc(audio->encoded_data_length);

    /* Assign encoder */
    audio->encoder = encoder;
    audio->stream = guac_client_alloc_stream(client);

    /* Ensure socket within new stream is threadsafe */
    guac_socket_require_threadsafe(audio->stream->socket);

    return audio;
}

void guac_audio_stream_begin(guac_audio_stream* audio, int rate, int channels, int bps) {

    /* Load PCM properties */
    audio->rate = rate;
    audio->channels = channels;
    audio->bps = bps;

    /* Reset write counter */
    audio->pcm_bytes_written = 0;

    /* Call handler */
    audio->encoder->begin_handler(audio);

}

void guac_audio_stream_end(guac_audio_stream* audio) {

    double duration;

    /* Flush stream and finish encoding */
    guac_audio_stream_flush(audio);
    audio->encoder->end_handler(audio);

    /* Calculate duration of PCM data */
    duration = ((double) (audio->pcm_bytes_written * 1000 * 8))
                / audio->rate / audio->channels / audio->bps;

    /* Send audio */
    guac_protocol_send_audio(audio->stream->socket,
            0, audio->encoder->mimetype,
            duration, audio->encoded_data, audio->encoded_data_used);

    /* Clear data */
    audio->encoded_data_used = 0;

}

void guac_audio_stream_free(guac_audio_stream* audio) {
    free(audio->pcm_data);
    free(audio);
}

void guac_audio_stream_write_pcm(guac_audio_stream* audio, 
        const unsigned char* data, int length) {

    /* Update counter */
    audio->pcm_bytes_written += length;

    /* Resize audio buffer if necessary */
    if (length > audio->length) {

        /* Resize to double provided length */
        audio->length = length*2;
        audio->pcm_data = realloc(audio->pcm_data, audio->length);

    }

    /* Flush if necessary */
    if (audio->used + length > audio->length)
        guac_audio_stream_flush(audio);

    /* Append to buffer */
    memcpy(&(audio->pcm_data[audio->used]), data, length);
    audio->used += length;

}

void guac_audio_stream_flush(guac_audio_stream* audio) {

    /* If data in buffer */
    if (audio->used != 0) {

        /* Write data */
        audio->encoder->write_handler(audio,
                audio->pcm_data, audio->used);

        /* Reset buffer */
        audio->used = 0;

    }

}

void guac_audio_stream_write_encoded(guac_audio_stream* audio,
        const unsigned char* data, int length) {

    /* Resize audio buffer if necessary */
    if (audio->encoded_data_used + length > audio->encoded_data_length) {

        /* Increase to double concatenated size to accomodate */
        audio->encoded_data_length = (audio->encoded_data_length + length)*2;
        audio->encoded_data = realloc(audio->encoded_data,
                audio->encoded_data_length);

    }

    /* Append to buffer */
    memcpy(&(audio->encoded_data[audio->encoded_data_used]), data, length);
    audio->encoded_data_used += length;

}