wav_playlist.c

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/* $Id: wav_playlist.c 919 2007-01-31 21:09:04Z bennylp $ */
/* 
 * Copyright (C) 2003-2007 Benny Prijono <[e-mail]>
 *
 * Original author:
 *  David Clark <vdc1048 @ tx.rr.com>
 *
 * This program 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.
 *
 * This program 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 this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA 
 */
#include <pjmedia/wav_playlist.h>
#include <pjmedia/errno.h>
#include <pjmedia/wave.h>
#include <pj/assert.h>
#include <pj/file_access.h>
#include <pj/file_io.h>
#include <pj/log.h>
#include <pj/pool.h>
#include <pj/string.h>

#define THIS_FILE	    "wav_playlist.c"

#define SIGNATURE	    PJMEDIA_PORT_SIGNATURE('P', 'l', 's', 't')
#define BYTES_PER_SAMPLE    2


#if 1
#   define TRACE_(x)	PJ_LOG(4,x)
#else
#   define TRACE_(x)
#endif

#if defined(PJ_IS_BIG_ENDIAN) && PJ_IS_BIG_ENDIAN!=0
    static void samples_to_host(pj_int16_t *samples, unsigned count)
    {
	unsigned i;
	for (i=0; i<count; ++i) {
	    samples[i] = pj_swap16(samples[i]);
	}
    }
#else
#   define samples_to_host(samples,count)
#endif


struct playlist_port
{
    pjmedia_port     base;
    unsigned	     options;
    pj_bool_t	     eof;
    pj_size_t	     bufsize;
    char	    *buf;
    char	    *readpos;

    pj_off_t        *fsize_list;
    unsigned        *start_data_list;
    pj_off_t        *fpos_list;
    pj_oshandle_t   *fd_list;	    /* list of file descriptors	*/
    int              current_file;  /* index of current file.	*/
    int              max_file;	    /* how many files.		*/

    pj_status_t	   (*cb)(pjmedia_port*, void*);
};


static pj_status_t file_list_get_frame(pjmedia_port *this_port,
				       pjmedia_frame *frame);
static pj_status_t file_list_on_destroy(pjmedia_port *this_port);


static struct playlist_port *create_file_list_port(pj_pool_t *pool,
						   const pj_str_t *name)
{
    struct playlist_port *port;

    port = pj_pool_zalloc(pool, sizeof(struct playlist_port));
    if (!port)
	return NULL;

    /* Put in default values.
     * These will be overriden once the file is read.
     */
    pjmedia_port_info_init(&port->base.info, name, SIGNATURE,
			   8000, 1, 16, 80);

    port->base.get_frame = &file_list_get_frame;
    port->base.on_destroy = &file_list_on_destroy;

    return port;
}


/*
 * Fill buffer for file_list operations.
 */
static pj_status_t file_fill_buffer(struct playlist_port *fport)
{
    pj_ssize_t size_left = fport->bufsize;
    unsigned size_to_read;
    pj_ssize_t size;
    pj_status_t status;
    int current_file = fport->current_file;

    /* Can't read file if EOF and loop flag is disabled */
    if (fport->eof)
	return PJ_EEOF;

    while (size_left > 0)
    {
	/* Calculate how many bytes to read in this run. */
	size = size_to_read = size_left;
	status = pj_file_read(fport->fd_list[current_file],
			      &fport->buf[fport->bufsize-size_left],
			      &size);
	if (status != PJ_SUCCESS)
	    return status;
	
	if (size < 0)
	{
	    /* Should return more appropriate error code here.. */
	    return PJ_ECANCELLED;
	}
	
	size_left -= size;
	fport->fpos_list[current_file] += size;
	
	/* If size is less than size_to_read, it indicates that we've
	 * encountered EOF. Rewind the file.
	 */
	if (size < (pj_ssize_t)size_to_read)
	{
	    /* Rewind the file for the next iteration */
	    fport->fpos_list[current_file] = 
		fport->start_data_list[current_file];
	    pj_file_setpos(fport->fd_list[current_file], 
			   fport->fpos_list[current_file], PJ_SEEK_SET);

	    /* Move to next file */
	    current_file++;
	    fport->current_file = current_file;

	    if (fport->current_file == fport->max_file)
	    {
		/* All files have been played. Call callback, if any. */
		if (fport->cb)
		{
		    PJ_LOG(5,(THIS_FILE,
			      "File port %.*s EOF, calling callback",
			      (int)fport->base.info.name.slen,
			      fport->base.info.name.ptr));
		    
		    fport->eof = PJ_TRUE;

		    status = (*fport->cb)(&fport->base,
					  fport->base.port_data.pdata);

		    if (status != PJ_SUCCESS)
		    {
			/* This will crash if file port is destroyed in the
			 * callback, that's why we set the eof flag before
			 * calling the callback:
			 fport->eof = PJ_TRUE;
			 */
			return status;
		    }

		    fport->eof = PJ_FALSE;
		}


		if (fport->options & PJMEDIA_FILE_NO_LOOP)
		{
		    PJ_LOG(5,(THIS_FILE, "File port %.*s EOF, stopping..",
			      (int)fport->base.info.name.slen,
			      fport->base.info.name.ptr));
		    fport->eof = PJ_TRUE;
		    return PJ_EEOF;
		}
		else
		{
		    PJ_LOG(5,(THIS_FILE, "File port %.*s EOF, rewinding..",
			      (int)fport->base.info.name.slen,
			      fport->base.info.name.ptr));
		    
		    /* start with first file again. */
		    fport->current_file = current_file = 0;
		    fport->fpos_list[0] = fport->start_data_list[0];
		    pj_file_setpos(fport->fd_list[0], fport->fpos_list[0],
				   PJ_SEEK_SET);
		}		
		
	    } /* if current_file == max_file */

	} /* size < size_to_read */

    } /* while () */
    
    /* Convert samples to host rep */
    samples_to_host((pj_int16_t*)fport->buf, fport->bufsize/BYTES_PER_SAMPLE);
    
    return PJ_SUCCESS;
}


/*
 * Create wave list player.
 */
PJ_DEF(pj_status_t) pjmedia_wav_playlist_create(pj_pool_t *pool,
						const pj_str_t *port_label,
						const pj_str_t file_list[],
						int file_count,
						unsigned ptime,
						unsigned options,
						pj_ssize_t buff_size,
						pjmedia_port **p_port)
{
    struct playlist_port *fport;
    pj_off_t pos;
    pj_status_t status;
    int index;
    pj_bool_t has_wave_info = PJ_FALSE;
    pj_str_t tmp_port_label;
    char filename[PJ_MAXPATH];	/* filename for open operations.    */


    /* Check arguments. */
    PJ_ASSERT_RETURN(pool && file_list && file_count && p_port, PJ_EINVAL);

    /* Normalize port_label */
    if (port_label == NULL || port_label->slen == 0) {
	tmp_port_label = pj_str("WAV playlist");
	port_label = &tmp_port_label;
    }

    /* Be sure all files exist	*/
    for (index=0; index<file_count; index++) {

	PJ_ASSERT_RETURN(file_list[index].slen < PJ_MAXPATH, PJ_ENAMETOOLONG);

	pj_memcpy(filename, file_list[index].ptr, file_list[index].slen);
	filename[file_list[index].slen] = '\0';

    	/* Check the file really exists. */
    	if (!pj_file_exists(filename)) {
	    PJ_LOG(4,(THIS_FILE,
		      "WAV playlist error: file '%s' not found",
	      	      filename));
	    return PJ_ENOTFOUND;
    	}
    }

    /* Normalize ptime */
    if (ptime == 0)
	ptime = 20;

    /* Create fport instance. */
    fport = create_file_list_port(pool, port_label);
    if (!fport) {
	return PJ_ENOMEM;
    }

    /* start with the first file. */
    fport->current_file = 0;
    fport->max_file = file_count;

    /* Create file descriptor list */
    fport->fd_list = pj_pool_zalloc(pool, sizeof(pj_oshandle_t)*file_count);
    if (!fport->fd_list) {
	return PJ_ENOMEM;
    }

    /* Create file size list */
    fport->fsize_list = pj_pool_alloc(pool, sizeof(pj_off_t)*file_count);
    if (!fport->fsize_list) {
	return PJ_ENOMEM;
    }

    /* Create start of WAVE data list */
    fport->start_data_list = pj_pool_alloc(pool, sizeof(unsigned)*file_count);
    if (!fport->start_data_list) {
	return PJ_ENOMEM;
    }

    /* Create file position list */
    fport->fpos_list = pj_pool_alloc(pool, sizeof(pj_off_t)*file_count);
    if (!fport->fpos_list) {
	return PJ_ENOMEM;
    }

    /* Create file buffer once for this operation.
     */
    if (buff_size < 1) buff_size = PJMEDIA_FILE_PORT_BUFSIZE;
    fport->bufsize = buff_size;


    /* Create buffer. */
    fport->buf = pj_pool_alloc(pool, fport->bufsize);
    if (!fport->buf) {
	return PJ_ENOMEM;
    }

    /* Initialize port */
    fport->options = options;
    fport->readpos = fport->buf;