wav_playlist.c

一个开源的sip源代码

    fport->options = options;
    fport->readpos = fport->buf;


    /* ok run this for all files to be sure all are good for playback. */
    for (index=file_count-1; index>=0; index--) {

	pjmedia_wave_hdr wavehdr;
	pj_ssize_t size_to_read, size_read;

	/* we end with the last one so we are good to go if still in function*/
	pj_memcpy(filename, file_list[index].ptr, file_list[index].slen);
	filename[file_list[index].slen] = '\0';

	/* Get the file size. */
	fport->current_file = index;
	fport->fsize_list[index] = pj_file_size(filename);
	
	/* Size must be more than WAVE header size */
	if (fport->fsize_list[index] <= sizeof(pjmedia_wave_hdr)) {
	    status = PJMEDIA_ENOTVALIDWAVE;
	    goto on_error;
	}
	
	/* Open file. */
	status = pj_file_open( pool, filename, PJ_O_RDONLY, 
			       &fport->fd_list[index]);
	if (status != PJ_SUCCESS)
	    goto on_error;
	
	/* Read the file header plus fmt header only. */
	size_read = size_to_read = sizeof(wavehdr) - 8;
	status = pj_file_read( fport->fd_list[index], &wavehdr, &size_read);
	if (status != PJ_SUCCESS) {
	    goto on_error;
	}

	if (size_read != size_to_read) {
	    status = PJMEDIA_ENOTVALIDWAVE;
	    goto on_error;
	}
	
	/* Normalize WAVE header fields values from little-endian to host
	 * byte order.
	 */
	pjmedia_wave_hdr_file_to_host(&wavehdr);
	
	/* Validate WAVE file. */
	if (wavehdr.riff_hdr.riff != PJMEDIA_RIFF_TAG ||
	    wavehdr.riff_hdr.wave != PJMEDIA_WAVE_TAG ||
	    wavehdr.fmt_hdr.fmt != PJMEDIA_FMT_TAG)
	{
	    TRACE_((THIS_FILE,
		"actual value|expected riff=%x|%x, wave=%x|%x fmt=%x|%x",
		wavehdr.riff_hdr.riff, PJMEDIA_RIFF_TAG,
		wavehdr.riff_hdr.wave, PJMEDIA_WAVE_TAG,
		wavehdr.fmt_hdr.fmt, PJMEDIA_FMT_TAG));
	    status = PJMEDIA_ENOTVALIDWAVE;
	    goto on_error;
	}
	
	/* Must be PCM with 16bits per sample */
	if (wavehdr.fmt_hdr.fmt_tag != 1 ||
	    wavehdr.fmt_hdr.bits_per_sample != 16)
	{
	    status = PJMEDIA_EWAVEUNSUPP;
	    goto on_error;
	}
	
	/* Block align must be 2*nchannels */
	if (wavehdr.fmt_hdr.block_align != 
		wavehdr.fmt_hdr.nchan * BYTES_PER_SAMPLE)
	{
	    status = PJMEDIA_EWAVEUNSUPP;
	    goto on_error;
	}
	
	/* If length of fmt_header is greater than 16, skip the remaining
	 * fmt header data.
	 */
	if (wavehdr.fmt_hdr.len > 16) {
	    size_to_read = wavehdr.fmt_hdr.len - 16;
	    status = pj_file_setpos(fport->fd_list[index], size_to_read, 
				    PJ_SEEK_CUR);
	    if (status != PJ_SUCCESS) {
		goto on_error;
	    }
	}
	
	/* Repeat reading the WAVE file until we have 'data' chunk */
	for (;;) {
	    pjmedia_wave_subchunk subchunk;
	    size_read = 8;
	    status = pj_file_read(fport->fd_list[index], &subchunk, 
				  &size_read);
	    if (status != PJ_SUCCESS || size_read != 8) {
		status = PJMEDIA_EWAVETOOSHORT;
		goto on_error;
	    }
	    
	    /* Normalize endianness */
	    PJMEDIA_WAVE_NORMALIZE_SUBCHUNK(&subchunk);
	    
	    /* Break if this is "data" chunk */
	    if (subchunk.id == PJMEDIA_DATA_TAG) {
		wavehdr.data_hdr.data = PJMEDIA_DATA_TAG;
		wavehdr.data_hdr.len = subchunk.len;
		break;
	    }
	    
	    /* Otherwise skip the chunk contents */
	    size_to_read = subchunk.len;
	    status = pj_file_setpos(fport->fd_list[index], size_to_read, 
				    PJ_SEEK_CUR);
	    if (status != PJ_SUCCESS) {
		goto on_error;
	    }
	}
	
	/* Current file position now points to start of data */
	status = pj_file_getpos(fport->fd_list[index], &pos);
	fport->start_data_list[index] = (unsigned)pos;
	
	/* Validate length. */
	if (wavehdr.data_hdr.len != fport->fsize_list[index] - 
				       fport->start_data_list[index]) 
	{
	    status = PJMEDIA_EWAVEUNSUPP;
	    goto on_error;
	}
	if (wavehdr.data_hdr.len < 400) {
	    status = PJMEDIA_EWAVETOOSHORT;
	    goto on_error;
	}
	
	/* It seems like we have a valid WAVE file. */
	
	/* Update port info if we don't have one, otherwise check
	 * that the WAV file has the same attributes as previous files. 
	 */
	if (!has_wave_info) {
	    fport->base.info.channel_count = wavehdr.fmt_hdr.nchan;
	    fport->base.info.clock_rate = wavehdr.fmt_hdr.sample_rate;
	    fport->base.info.bits_per_sample = wavehdr.fmt_hdr.bits_per_sample;
	    fport->base.info.samples_per_frame = fport->base.info.clock_rate *
						 wavehdr.fmt_hdr.nchan *
						 ptime / 1000;
	    fport->base.info.bytes_per_frame =
		fport->base.info.samples_per_frame *
		fport->base.info.bits_per_sample / 8;

	    has_wave_info = PJ_TRUE;

	} else {

	    /* Check that this file has the same characteristics as the other
	     * files.
	     */
	    if (wavehdr.fmt_hdr.nchan != fport->base.info.channel_count ||
		wavehdr.fmt_hdr.sample_rate != fport->base.info.clock_rate ||
		wavehdr.fmt_hdr.bits_per_sample != fport->base.info.bits_per_sample)
	    {
		/* This file has different characteristics than the other 
		 * files. 
		 */
		PJ_LOG(4,(THIS_FILE,
		          "WAV playlist error: file '%s' has differrent number"
			  " of channels, sample rate, or bits per sample",
	      		  filename));
		status = PJMEDIA_EWAVEUNSUPP;
		goto on_error;
	    }

	}
	
	
	/* Set initial position of the file. */
	fport->fpos_list[index] = fport->start_data_list[index];
    }

    /* Fill up the buffer. */
    status = file_fill_buffer(fport);
    if (status != PJ_SUCCESS) {
	goto on_error;
    }
    
    /* Done. */
    
    *p_port = &fport->base;
    
    PJ_LOG(4,(THIS_FILE,
	     "WAV playlist '%.*s' created: samp.rate=%d, ch=%d, bufsize=%uKB",
	     (int)port_label->slen,
	     port_label->ptr,
	     fport->base.info.clock_rate,
	     fport->base.info.channel_count,
	     fport->bufsize / 1000));
    
    return PJ_SUCCESS;

on_error:
    for (index=0; index<file_count; ++index) {
	if (fport->fd_list[index] != 0)
	    pj_file_close(fport->fd_list[index]);
    }

    return status;
}


/*
 * Register a callback to be called when the file reading has reached the
 * end of the last file.
 */
PJ_DEF(pj_status_t)
pjmedia_wav_playlist_set_eof_cb(pjmedia_port *port,
			        void *user_data,
			        pj_status_t (*cb)(pjmedia_port *port,
						  void *usr_data))
{
    struct playlist_port *fport;

    /* Sanity check */
    PJ_ASSERT_RETURN(port, PJ_EINVAL);

    /* Check that this is really a playlist port */
    PJ_ASSERT_RETURN(port->info.signature == SIGNATURE, PJ_EINVALIDOP);

    fport = (struct playlist_port*) port;

    fport->base.port_data.pdata = user_data;
    fport->cb = cb;

    return PJ_SUCCESS;
}


/*
 * Get frame from file for file_list operation
 */
static pj_status_t file_list_get_frame(pjmedia_port *this_port,
				       pjmedia_frame *frame)
{
    struct playlist_port *fport = (struct playlist_port*)this_port;
    unsigned frame_size;
    pj_status_t status;

    pj_assert(fport->base.info.signature == SIGNATURE);

    //frame_size = fport->base.info.bytes_per_frame;
    //pj_assert(frame->size == frame_size);
    frame_size = frame->size;

    /* Copy frame from buffer. */
    frame->type = PJMEDIA_FRAME_TYPE_AUDIO;
    frame->size = frame_size;
    frame->timestamp.u64 = 0;

    if (fport->readpos + frame_size <= fport->buf + fport->bufsize) {

	/* Read contiguous buffer. */
	pj_memcpy(frame->buf, fport->readpos, frame_size);

	/* Fill up the buffer if all has been read. */
	fport->readpos += frame_size;
	if (fport->readpos == fport->buf + fport->bufsize) {
	    fport->readpos = fport->buf;

	    status = file_fill_buffer(fport);
	    if (status != PJ_SUCCESS) {
		frame->type = PJMEDIA_FRAME_TYPE_NONE;
		frame->size = 0;
		return status;
	    }
	}
    } else {
	unsigned endread;

	/* Split read.
	 * First stage: read until end of buffer.
	 */
	endread = (fport->buf+fport->bufsize) - fport->readpos;
	pj_memcpy(frame->buf, fport->readpos, endread);

	/* Second stage: fill up buffer, and read from the start of buffer. */
	status = file_fill_buffer(fport);
	if (status != PJ_SUCCESS) {
	    pj_bzero(((char*)frame->buf)+endread, frame_size-endread);
	    return status;
	}

	pj_memcpy(((char*)frame->buf)+endread, fport->buf, frame_size-endread);
	fport->readpos = fport->buf + (frame_size - endread);
    }

    return PJ_SUCCESS;
}


/*
 * Destroy port.
 */
static pj_status_t file_list_on_destroy(pjmedia_port *this_port)
{
    struct playlist_port *fport = (struct playlist_port*) this_port;
    int index;

    pj_assert(this_port->info.signature == SIGNATURE);

    for (index=0; index<fport->max_file; index++)
	pj_file_close(fport->fd_list[index]);

    return PJ_SUCCESS;
}