hb_list implementation

/**********************************************************************
 * hb_list implementation
 **********************************************************************
 * Basic and slow, but enough for what we need
 *********************************************************************/

#define HB_LIST_DEFAULT_SIZE 20

struct hb_list_s
{
    /* Pointers to items in the list */
    void ** items;

    /* How many (void *) allocated in 'items' */
    int     items_alloc;

    /* How many valid pointers in 'items' */
    int     items_count;
};

/**********************************************************************
 * hb_list_init
 **********************************************************************
 * Allocates an empty list ready for HB_LIST_DEFAULT_SIZE items
 *********************************************************************/
hb_list_t * hb_list_init()
{
    hb_list_t * l;

    l              = calloc( sizeof( hb_list_t ), 1 );
    l->items       = calloc( HB_LIST_DEFAULT_SIZE * sizeof( void * ), 1 );
    l->items_alloc = HB_LIST_DEFAULT_SIZE;

    return l;
}

/**********************************************************************
 * hb_list_count
 **********************************************************************
 * Returns the number of items currently in the list
 *********************************************************************/
int hb_list_count( hb_list_t * l )
{
    return l->items_count;
}

/**********************************************************************
 * hb_list_add
 **********************************************************************
 * Adds an item at the end of the list, making it bigger if necessary.
 * Can safely be called with a NULL pointer to add, it will be ignored.
 *********************************************************************/
void hb_list_add( hb_list_t * l, void * p )
{
    if( !p )
    {
        return;
    }

    if( l->items_count == l->items_alloc )
    {
        /* We need a bigger boat */
        l->items_alloc += HB_LIST_DEFAULT_SIZE;
        l->items        = realloc( l->items,
                                   l->items_alloc * sizeof( void * ) );
    }

    l->items[l->items_count] = p;
    (l->items_count)++;
}

/**********************************************************************
 * hb_list_rem
 **********************************************************************
 * Remove an item from the list. Bad things will happen if called
 * with a NULL pointer or if the item is not in the list.
 *********************************************************************/
void hb_list_rem( hb_list_t * l, void * p )
{
    int i;

    /* Find the item in the list */
    for( i = 0; i < l->items_count; i++ )
    {
        if( l->items[i] == p )
        {
            break;
        }
    }

    /* Shift all items after it sizeof( void * ) bytes earlier */
    memmove( &l->items[i], &l->items[i+1],
             ( l->items_count - i - 1 ) * sizeof( void * ) );

    (l->items_count)--;
}

/**********************************************************************
 * hb_list_item
 **********************************************************************
 * Returns item at position i, or NULL if there are not that many
 * items in the list
 *********************************************************************/
void * hb_list_item( hb_list_t * l, int i )
{
    if( i < 0 || i >= l->items_count )
    {
        return NULL;
    }

    return l->items[i];
}

/**********************************************************************
 * hb_list_bytes
 **********************************************************************
 * Assuming all items are of type hb_buffer_t, returns the total
 * number of bytes in the list
 *********************************************************************/
int hb_list_bytes( hb_list_t * l )
{
    hb_buffer_t * buf;
    int           ret;
    int           i;

    ret = 0;
    for( i = 0; i < hb_list_count( l ); i++ )
    {
        buf  = hb_list_item( l, i );
        ret += buf->size - buf->cur;
    }

    return ret;
}

/**********************************************************************
 * hb_list_seebytes
 **********************************************************************
 * Assuming all items are of type hb_buffer_t, copy bytes from
 * the list to , keeping the list unmodified.
 *********************************************************************/
void hb_list_seebytes( hb_list_t * l, uint8_t * dst, int size )
{
    hb_buffer_t * buf;
    int           copied;
    int           copying;
    int           i;

    for( i = 0, copied = 0; copied < size; i++ )
    {
        buf     = hb_list_item( l, i );
        copying = MIN( buf->size - buf->cur, size - copied );
        memcpy( &dst[copied], &buf->data[buf->cur], copying );
        copied += copying;
    }
}

/**********************************************************************
 * hb_list_getbytes
 **********************************************************************
 * Assuming all items are of type hb_buffer_t, copy bytes from
 * the list to . What's copied is removed from the list.
 * The variable pointed by is set to the PTS of the buffer the
 * first byte has been got from.
 * The variable pointed by is set to the position of that byte
 * in that buffer.
 *********************************************************************/
void hb_list_getbytes( hb_list_t * l, uint8_t * dst, int size,
                       uint64_t * pts, uint64_t * pos )
{
    hb_buffer_t * buf;
    int           copied;
    int           copying;
    uint8_t       has_pts;

    /* So we won't have to deal with NULL pointers */
     uint64_t dummy1, dummy2;

    if( !pts ) pts = &dummy1;
    if( !pos ) pos = &dummy2;

    for( copied = 0, has_pts = 0; copied < size;  )
    {
        buf     = hb_list_item( l, 0 );
        copying = MIN( buf->size - buf->cur, size - copied );
        memcpy( &dst[copied], &buf->data[buf->cur], copying );

        if( !has_pts )
        {
            *pts    = buf->start;
            *pos    = buf->cur;
            has_pts = 1;
        }

        buf->cur += copying;
        if( buf->cur >= buf->size )
        {
            hb_list_rem( l, buf );
            hb_buffer_close( &buf );
        }

        copied += copying;
    }
}

/**********************************************************************
 * hb_list_empty
 **********************************************************************
 * Assuming all items are of type hb_buffer_t, close them all and
 * close the list.
 *********************************************************************/
void hb_list_empty( hb_list_t ** _l )
{
    hb_list_t * l = *_l;
    hb_buffer_t * b;

    while( ( b = hb_list_item( l, 0 ) ) )
    {
        hb_list_rem( l, b );
        hb_buffer_close( &b );
    }

    hb_list_close( _l );
}

/**********************************************************************
 * hb_list_close
 **********************************************************************
 * Free memory allocated by hb_list_init. Does NOT free contents of
 * items still in the list.
 *********************************************************************/
void hb_list_close( hb_list_t ** _l )
{
    hb_list_t * l = *_l;

    free( l->items );
    free( l );

    *_l = NULL;
}