source: downloads/openal-0.0.8/src/al_mixmanager.c @ 17

/* -*- mode: C; tab-width:8; c-basic-offset:8 -*-
 * vi:set ts=8:
 *
 * al_mixmanager.c
 *
 * Definition and manipulated of ALMixManager objects.
 */
#include "al_siteconfig.h"

#include <stdlib.h>
#include <stdio.h>
#include <string.h>

#include "al_debug.h"
#include "al_types.h"
#include "al_mixmanager.h"

#include "mixaudio16.h"

/*
 * _alMixManagerInit( ALMixManager *mixman, ALuint size )
 *
 * Initializes the already allocated ALMixManager object *mixman, to
 * accomodate at least size entries.
 */
ALboolean _alMixManagerInit( ALMixManager *mixman, ALuint size ) {
        void *temp;

        if(size == 0) {
                return AL_FALSE;
        }

        if(size > MAXMIXSOURCES) {
                return AL_FALSE;
        }

        mixman->size = size;
        mixman->index = 0;

        temp = realloc(mixman->pool, size * sizeof *mixman->pool);
        if(temp == NULL) {
                perror("malloc");
                return AL_FALSE;
        }
        mixman->pool = temp;

        memset(mixman->pool, 0, size * sizeof *mixman->pool);

        return AL_TRUE;
}

/*
 * _alMixManagerDestroy( ALMixManager *mixman )
 *
 * Performs finalization on the ALMixManager object *mixman.
 */
void _alMixManagerDestroy( ALMixManager *mixman ) {
        free( mixman->pool );
        mixman->pool = NULL;

        mixman->index = 0;
        mixman->size  = 0;

        /* let caller free mixman, if needed */

        return;
}


/*
 * _alMixManagerAdd( ALMixManager *mixman, ALvoid *dataptr, int bytes_to_write )
 *
 * Adds an entry to the ALMixManager object *mixman, with data dataptr of
 * length bytes_to_write in bytes.
 *
 * assumes locked mixer
 *
 * FIXME: sort by bytes?
 */
void _alMixManagerAdd( ALMixManager *mixman, void *dataptr, int bytes_to_write ) {
        void *temp;

        if(mixman->index >= mixman->size) {
                /* time to resize */
                int newsize = mixman->size * 2;

                temp = realloc(mixman->pool, newsize * sizeof *mixman->pool);
                if(temp == NULL) {
                        /* oh dear */
                        return;
                }

                mixman->pool = temp;
                mixman->size = newsize;
        }

        mixman->pool[mixman->index].data  = dataptr;
        mixman->pool[mixman->index].bytes = bytes_to_write;

        mixman->index++;

        return;
}


/*
 * _alMixManagerMix( ALMixManager *mixman, ALMixFunc *mf, ALvoid *dataptr )
 *
 * Mixes each entry in ALMixManager *mixman, using mixing functions from
 * ALMixFunc, populating dataptr.
 *
 *  assumes locked mixer
 */
void _alMixManagerMix( ALMixManager *mixman, ALMixFunc *mf, ALvoid *dataptr ) {
        if( mixman == NULL ) {
                return;
        }

        if( mf == NULL ) {
                return;
        }

        if(mixman->index > mf->max) {
                /* bite the bullet and do it the long way */
                mf->func_n(dataptr, mixman->pool, mixman->index);
        } else {
                /* do the mixing */
                mf->funcs[mixman->index](dataptr, mixman->pool);
        }

        while(mixman->index--) {
                mixman->pool[mixman->index].data = NULL;
        }

        /* reset index */
        mixman->index = 0;

        return;
}