modules/xml/producer_xml.c

/*
 * producer_xml.c -- a libxml2 parser of mlt service networks
 * Copyright (C) 2003-2020 Meltytech, LLC
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 */

// TODO: destroy unreferenced producers (they are currently destroyed
//       when the returned producer is closed).

#include "common.h"

#include <framework/mlt.h>
#include <framework/mlt_log.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <unistd.h>

#include <libxml/parser.h>
#include <libxml/parserInternals.h> // for xmlCreateFileParserCtxt
#include <libxml/tree.h>

#define BRANCH_SIG_LEN 4000

#define _x (const xmlChar*)
#define _s (const char*)

#undef DEBUG
#ifdef DEBUG
extern xmlDocPtr xml_make_doc( mlt_service service );
#endif

enum service_type
{
	mlt_invalid_type,
	mlt_unknown_type,
	mlt_producer_type,
	mlt_playlist_type,
	mlt_entry_type,
	mlt_tractor_type,
	mlt_multitrack_type,
	mlt_filter_type,
	mlt_transition_type,
	mlt_consumer_type,
	mlt_field_type,
	mlt_services_type,
	mlt_dummy_filter_type,
	mlt_dummy_transition_type,
	mlt_dummy_producer_type,
	mlt_dummy_consumer_type
};

struct deserialise_context_s
{
	mlt_deque stack_types;
	mlt_deque stack_service;
	mlt_properties producer_map;
	mlt_properties destructors;
	char *property;
	int is_value;
	xmlDocPtr value_doc;
	mlt_deque stack_node;
	xmlDocPtr entity_doc;
	int entity_is_replace;
	mlt_deque stack_branch;
	const xmlChar *publicId;
	const xmlChar *systemId;
	mlt_properties params;
	mlt_profile profile;
	mlt_profile consumer_profile;
	int pass;
	char *lc_numeric;
	mlt_consumer consumer;
	int multi_consumer;
	int consumer_count;
	int seekable;
	mlt_consumer qglsl;
};
typedef struct deserialise_context_s *deserialise_context;

/** Trim the leading and trailing whitespace from a string in-place.
*/
static char* trim( char *s )
{
	int n;
	if ( s && ( n = strlen( s ) ) )
	{
		int i = 0;
		while ( i < n && isspace( s[i] ) ) i++;
		while ( --n && isspace( s[n] ) );
		n = n - i + 1;
		if ( n > 0 )
			memmove( s, s + i, n );
		s[ n ] = 0;
	}
	return s;
}

/** Convert the numerical current branch address to a dot-delimited string.
*/
static char *serialise_branch( deserialise_context context, char *s )
{
	int i, n = mlt_deque_count( context->stack_branch );

	s[0] = 0;
	for ( i = 0; i < n - 1; i++ )
	{
		int len = strlen( s );
		snprintf( s + len, BRANCH_SIG_LEN - len, "%lu.",
			(unsigned long) mlt_deque_peek( context->stack_branch, i ) );
	}
	return s;
}

/** Push a service.
*/

static void context_push_service( deserialise_context context, mlt_service that, enum service_type type )
{
	mlt_deque_push_back( context->stack_service, that );
	mlt_deque_push_back_int( context->stack_types, type );

	// Record the tree branch on which this service lives
	if ( that != NULL && mlt_properties_get( MLT_SERVICE_PROPERTIES( that ), "_xml_branch" ) == NULL )
	{
		char s[ BRANCH_SIG_LEN ];
		mlt_properties_set_string( MLT_SERVICE_PROPERTIES( that ), "_xml_branch", serialise_branch( context, s ) );
	}
}

/** Pop a service.
*/

static mlt_service context_pop_service( deserialise_context context, enum service_type *type )
{
	mlt_service result = NULL;

	if ( type ) *type = mlt_invalid_type;
	if ( mlt_deque_count( context->stack_service ) > 0 )
	{
		result = mlt_deque_pop_back( context->stack_service );
		if ( type != NULL )
			*type = mlt_deque_pop_back_int( context->stack_types );
		// Set the service's profile and locale so mlt_property time-to-position conversions can get fps
		if ( result )
		{
			mlt_properties_set_data( MLT_SERVICE_PROPERTIES( result ), "_profile", context->profile, 0, NULL, NULL );
			mlt_properties_set_lcnumeric( MLT_SERVICE_PROPERTIES( result ), context->lc_numeric );
		}
	}
	return result;
}

/** Push a node.
*/

static void context_push_node( deserialise_context context, xmlNodePtr node )
{
	mlt_deque_push_back( context->stack_node, node );
}

/** Pop a node.
*/

static xmlNodePtr context_pop_node( deserialise_context context )
{
	return mlt_deque_pop_back( context->stack_node );
}


// Set the destructor on a new service
static void track_service( mlt_properties properties, void *service, mlt_destructor destructor )
{
	int registered = mlt_properties_get_int( properties, "registered" );
	char *key = mlt_properties_get( properties, "registered" );
	mlt_properties_set_data( properties, key, service, 0, destructor, NULL );
	mlt_properties_set_int( properties, "registered", ++ registered );
}

static inline int is_known_prefix(const char* resource)
{
	char *prefix = strchr(resource, ':');
	if (prefix) {
		const char *whitelist[] = {
			"alsa",
			"avfoundation",
			"dshow",
			"fbdev",
			"gdigrab",
			"jack",
			"lavfi",
			"oss",
			"pulse",
			"sndio",
			"video4linux2",
			"v4l2",
			"x11grab",
			"async",
			"cache",
			"concat",
			"crypto",
			"data",
			"ffrtmphttp",
			"file",
			"ftp",
			"fs",
			"gopher",
			"hls",
			"http",
			"httpproxy",
			"mmsh",
			"mmst",
			"pipe",
			"rtmp",
			"rtmpt",
			"rtp",
			"srtp",
			"subfile",
			"tcp",
			"udp",
			"udplite",
			"unix",
			"color",
			"colour"
		};
		size_t i, n = prefix - resource;
		for (i = 0; i < sizeof(whitelist) / sizeof(whitelist[0]); ++i) {
			if (!strncmp(whitelist[i], resource, n))
				return 1;
		}
	}
	return 0;
}

// Prepend the property value with the document root
static inline void qualify_property( deserialise_context context, mlt_properties properties, const char *name )
{
	const char *resource_orig = mlt_properties_get( properties, name );
	char *resource = mlt_properties_get( properties, name );
	if ( resource != NULL && resource[0] )
	{
		char *root = mlt_properties_get( context->producer_map, "root" );
		int n = strlen( root ) + strlen( resource ) + 2;
		size_t prefix_size = mlt_xml_prefix_size( properties, name, resource );

		// Strip off prefix.
		if ( prefix_size )
			resource += prefix_size;

		// Qualify file name properties
		if ( root != NULL && strcmp( root, "" ) )
		{
			char *full_resource = calloc( 1, n );
			int drive_letter = strlen(resource) > 3 && resource[1] == ':' &&
				(resource[2] == '/' || resource[2] == '\\');
			if (resource[0] != '/' && resource[0] != '\\' && !drive_letter && !is_known_prefix(resource))
			{
				if ( prefix_size )
					strncat( full_resource, resource_orig, prefix_size );
				strcat( full_resource, root );
				strcat( full_resource, "/" );
				strcat( full_resource, resource );
			}
			else
			{
				strcpy( full_resource, resource_orig );
			}
			mlt_properties_set_string( properties, name, full_resource );
			free( full_resource );
		}
	}
}


/** This function adds a producer to a playlist or multitrack when
    there is no entry or track element.
*/

static int add_producer( deserialise_context context, mlt_service service, mlt_position in, mlt_position out )
{
	// Return value (0 = service remains top of stack, 1 means it can be removed)
	int result = 0;

	// Get the parent producer
	enum service_type type = mlt_invalid_type;
	mlt_service container = context_pop_service( context, &type );
	int contained = 0;

	if ( service != NULL && container != NULL )
	{
		char *container_branch = mlt_properties_get( MLT_SERVICE_PROPERTIES( container ), "_xml_branch" );
		char *service_branch = mlt_properties_get( MLT_SERVICE_PROPERTIES( service ), "_xml_branch" );
		contained = !strncmp( container_branch, service_branch, strlen( container_branch ) );
	}

	if ( contained )
	{
		mlt_properties properties = MLT_SERVICE_PROPERTIES( service );
		char *hide_s = mlt_properties_get( properties, "hide" );

		// Indicate that this service is no longer top of stack
		result = 1;

		switch( type )
		{
			case mlt_tractor_type:
				{
					mlt_multitrack multitrack = mlt_tractor_multitrack( MLT_TRACTOR( container ) );
					mlt_multitrack_connect( multitrack, MLT_PRODUCER( service ), mlt_multitrack_count( multitrack ) );
				}
				break;
			case mlt_multitrack_type:
				{
					mlt_multitrack_connect( MLT_MULTITRACK( container ),
						MLT_PRODUCER( service ),
						mlt_multitrack_count( MLT_MULTITRACK( container ) ) );
				}
				break;
			case mlt_playlist_type:
				{
					mlt_playlist_append_io( MLT_PLAYLIST( container ), MLT_PRODUCER( service ), in, out );
				}
				break;
			default:
				result = 0;
				mlt_log_warning( NULL, "[producer_xml] Producer defined inside something that isn't a container\n" );
				break;
		};

		// Set the hide state of the track producer
		if ( hide_s != NULL )
		{
			if ( strcmp( hide_s, "video" ) == 0 )
				mlt_properties_set_int( properties, "hide", 1 );
			else if ( strcmp( hide_s, "audio" ) == 0 )
				mlt_properties_set_int( properties, "hide", 2 );
			else if ( strcmp( hide_s, "both" ) == 0 )
				mlt_properties_set_int( properties, "hide", 3 );
		}
	}

	// Put the parent producer back
	if ( container != NULL )
		context_push_service( context, container, type );

	return result;
}

/** Attach filters defined on that to this.
*/

static void attach_filters( mlt_service service, mlt_service that )
{
	if ( that != NULL )
	{
		int i = 0;
		mlt_filter filter = NULL;
		for ( i = 0; ( filter = mlt_service_filter( that, i ) ) != NULL; i ++ )
		{
			mlt_service_attach( service, filter );
			attach_filters( MLT_FILTER_SERVICE( filter ), MLT_FILTER_SERVICE( filter ) );
		}
	}
}

static void on_start_profile( deserialise_context context, const xmlChar *name, const xmlChar **atts)
{
	mlt_profile p = context->profile;
	for ( ; atts != NULL && *atts != NULL; atts += 2 )
	{
		if ( xmlStrcmp( atts[ 0 ], _x("name") ) == 0 || xmlStrcmp( atts[ 0 ], _x("profile") ) == 0 )
		{
			mlt_profile my_profile = mlt_profile_init( _s(atts[ 1 ]) );
			if ( my_profile )
			{
				p->description = strdup( my_profile->description );
				p->display_aspect_den = my_profile->display_aspect_den;
				p->display_aspect_num = my_profile->display_aspect_num;
				p->frame_rate_den = my_profile->frame_rate_den;
				p->frame_rate_num = my_profile->frame_rate_num;
				p->width = my_profile->width;
				p->height = my_profile->height;
				p->progressive = my_profile->progressive;
				p->sample_aspect_den = my_profile->sample_aspect_den;
				p->sample_aspect_num = my_profile->sample_aspect_num;
				p->colorspace = my_profile->colorspace;
				p->is_explicit = 1;
				mlt_profile_close( my_profile );
			}
		}
		else if ( xmlStrcmp( atts[ 0 ], _x("description") ) == 0 )
		{
			free( p->description );
			p->description = strdup( _s(atts[ 1 ]) );
			p->is_explicit = 1;
		}
		else if ( xmlStrcmp( atts[ 0 ], _x("display_aspect_den") ) == 0 )
			p->display_aspect_den = strtol( _s(atts[ 1 ]), NULL, 0 );
		else if ( xmlStrcmp( atts[ 0 ], _x("display_aspect_num") ) == 0 )
			p->display_aspect_num = strtol( _s(atts[ 1 ]), NULL, 0 );
		else if ( xmlStrcmp( atts[ 0 ], _x("sample_aspect_num") ) == 0 )
			p->sample_aspect_num = strtol( _s(atts[ 1 ]), NULL, 0 );
		else if ( xmlStrcmp( atts[ 0 ], _x("sample_aspect_den") ) == 0 )
			p->sample_aspect_den = strtol( _s(atts[ 1 ]), NULL, 0 );
		else if ( xmlStrcmp( atts[ 0 ], _x("width") ) == 0 )
			p->width = strtol( _s(atts[ 1 ]), NULL, 0 );
		else if ( xmlStrcmp( atts[ 0 ], _x("height") ) == 0 )
			p->height = strtol( _s(atts[ 1 ]), NULL, 0 );
		else if ( xmlStrcmp( atts[ 0 ], _x("progressive") ) == 0 )
			p->progressive = strtol( _s(atts[ 1 ]), NULL, 0 );
		else if ( xmlStrcmp( atts[ 0 ], _x("frame_rate_num") ) == 0 )
			p->frame_rate_num = strtol( _s(atts[ 1 ]), NULL, 0 );
		else if ( xmlStrcmp( atts[ 0 ], _x("frame_rate_den") ) == 0 )
			p->frame_rate_den = strtol( _s(atts[ 1 ]), NULL, 0 );
		else if ( xmlStrcmp( atts[ 0 ], _x("colorspace") ) == 0 )
			p->colorspace = strtol( _s(atts[ 1 ]), NULL, 0 );
	}
}

static void on_start_tractor( deserialise_context context, const xmlChar *name, const xmlChar **atts)
{
	mlt_tractor tractor = mlt_tractor_new( );
	mlt_service service = MLT_TRACTOR_SERVICE( tractor );
	mlt_properties properties = MLT_SERVICE_PROPERTIES( service );

	track_service( context->destructors, service, (mlt_destructor) mlt_tractor_close );
	mlt_properties_set_lcnumeric( MLT_SERVICE_PROPERTIES( service ), context->lc_numeric );

	for ( ; atts != NULL && *atts != NULL; atts += 2 )
		mlt_properties_set_string( MLT_SERVICE_PROPERTIES( service ), (const char*) atts[0], atts[1] == NULL ? "" : (const char*) atts[1] );

	mlt_properties_set_int( MLT_TRACTOR_PROPERTIES( tractor ), "global_feed", 1 );

	if ( mlt_properties_get( properties, "id" ) != NULL )
		mlt_properties_set_data( context->producer_map, mlt_properties_get( properties, "id" ), service, 0, NULL, NULL );

	context_push_service( context, service, mlt_tractor_type );
}

static void on_end_tractor( deserialise_context context, const xmlChar *name )
{
	// Get the tractor
	enum service_type type;
	mlt_service tractor = context_pop_service( context, &type );

	if ( tractor != NULL && type == mlt_tractor_type )
	{
		// See if the tractor should be added to a playlist or multitrack
		if ( add_producer( context, tractor, 0, mlt_producer_get_out( MLT_PRODUCER( tractor ) ) ) == 0 )
			context_push_service( context, tractor, type );
	}
	else
	{
		mlt_log_error( NULL, "[producer_xml] Invalid state for tractor\n" );
	}
}

static void on_start_multitrack( deserialise_context context, const xmlChar *name, const xmlChar **atts)
{
	enum service_type type;
	mlt_service parent = context_pop_service( context, &type );

	// If we don't have a parent, then create one now, providing we're in a state where we can
	if ( parent == NULL || ( type == mlt_playlist_type || type == mlt_multitrack_type ) )
	{
		mlt_tractor tractor = NULL;
		// Push the parent back
		if ( parent != NULL )
			context_push_service( context, parent, type );

		// Create a tractor to contain the multitrack
		tractor = mlt_tractor_new( );
		parent = MLT_TRACTOR_SERVICE( tractor );
		track_service( context->destructors, parent, (mlt_destructor) mlt_tractor_close );
		mlt_properties_set_lcnumeric( MLT_SERVICE_PROPERTIES( parent ), context->lc_numeric );
		type = mlt_tractor_type;

		// Flag it as a synthesised tractor for clean up later
		mlt_properties_set_int( MLT_SERVICE_PROPERTIES( parent ), "loader_synth", 1 );
	}

	if ( type == mlt_tractor_type )
	{
		mlt_service service = MLT_SERVICE( mlt_tractor_multitrack( MLT_TRACTOR( parent ) ) );
		mlt_properties properties = MLT_SERVICE_PROPERTIES( service );
		for ( ; atts != NULL && *atts != NULL; atts += 2 )
			mlt_properties_set_string( properties, (const char*) atts[0], atts[1] == NULL ? "" : (const char*) atts[1] );

		if ( mlt_properties_get( properties, "id" ) != NULL )
			mlt_properties_set_data( context->producer_map, mlt_properties_get( properties,"id" ), service, 0, NULL, NULL );

		context_push_service( context, parent, type );
		context_push_service( context, service, mlt_multitrack_type );
	}
	else
	{
		mlt_log_error( NULL, "[producer_xml] Invalid multitrack position\n" );
	}
}

static void on_end_multitrack( deserialise_context context, const xmlChar *name )
{
	// Get the multitrack from the stack
	enum service_type type;
	mlt_service service = context_pop_service( context, &type );

	if ( service == NULL || type != mlt_multitrack_type )
		mlt_log_error( NULL, "[producer_xml] End multitrack in the wrong state...\n" );
}

static void on_start_playlist( deserialise_context context, const xmlChar *name, const xmlChar **atts)
{
	mlt_playlist playlist = mlt_playlist_new( context->profile );
	mlt_service service = MLT_PLAYLIST_SERVICE( playlist );
	mlt_properties properties = MLT_SERVICE_PROPERTIES( service );

	track_service( context->destructors, service, (mlt_destructor) mlt_playlist_close );

	for ( ; atts != NULL && *atts != NULL; atts += 2 )
	{
		mlt_properties_set_string( properties, (const char*) atts[0], atts[1] == NULL ? "" : (const char*) atts[1] );

		// Out will be overwritten later as we append, so we need to save it
		if ( xmlStrcmp( atts[ 0 ], _x("out") ) == 0 )
			mlt_properties_set_string( properties, "_xml.out", ( const char* )atts[ 1 ] );
	}

	if ( mlt_properties_get( properties, "id" ) != NULL )
		mlt_properties_set_data( context->producer_map, mlt_properties_get( properties, "id" ), service, 0, NULL, NULL );

	context_push_service( context, service, mlt_playlist_type );
}

static void on_end_playlist( deserialise_context context, const xmlChar *name )
{
	// Get the playlist from the stack
	enum service_type type;
	mlt_service service = context_pop_service( context, &type );

	if ( service != NULL && type == mlt_playlist_type )
	{
		mlt_properties properties = MLT_SERVICE_PROPERTIES( service );
		mlt_position in = -1;
		mlt_position out = -1;

		if ( mlt_properties_get( properties, "in" ) )
			in = mlt_properties_get_position( properties, "in" );
		if ( mlt_properties_get( properties, "out" ) )
			out = mlt_properties_get_position( properties, "out" );

		// See if the playlist should be added to a playlist or multitrack
		if ( add_producer( context, service, in, out ) == 0 )
			context_push_service( context, service, type );
	}
	else
	{
		mlt_log_error( NULL, "[producer_xml] Invalid state of playlist end %d\n", type );
	}
}

static void on_start_producer( deserialise_context context, const xmlChar *name, const xmlChar **atts)
{
	// use a dummy service to hold properties to allow arbitrary nesting
	mlt_service service = calloc( 1, sizeof( struct mlt_service_s ) );
	mlt_service_init( service, NULL );

	mlt_properties properties = MLT_SERVICE_PROPERTIES( service );

	context_push_service( context, service, mlt_dummy_producer_type );

	for ( ; atts != NULL && *atts != NULL; atts += 2 )
		mlt_properties_set_string( properties, (const char*) atts[0], atts[1] == NULL ? "" : (const char*) atts[1] );
}

static void on_end_producer( deserialise_context context, const xmlChar *name )
{
	enum service_type type;
	mlt_service service = context_pop_service( context, &type );
	mlt_properties properties = MLT_SERVICE_PROPERTIES( service );

	if ( service != NULL && type == mlt_dummy_producer_type )
	{
		mlt_service producer = NULL;

		qualify_property( context, properties, "resource" );
		char *resource = mlt_properties_get( properties, "resource" );

		// Let Kino-SMIL src be a synonym for resource
		if ( resource == NULL )
		{
			qualify_property( context, properties, "src" );
			resource = mlt_properties_get( properties, "src" );
		}

		// Instantiate the producer
		if ( mlt_properties_get( properties, "mlt_service" ) != NULL )
		{
			char *service_name = trim( mlt_properties_get( properties, "mlt_service" ) );
			if ( resource )
			{
				// If a document was saved as +INVALID.txt (see below), then ignore the mlt_service and
				// try to load it just from the resource. This is an attempt to recover the failed
				// producer in case, for example, a file returns.
				if (!strcmp("qtext", service_name)) {
					const char *text = mlt_properties_get( properties, "text" );
					if (text && !strcmp("INVALID", text)) {
						service_name = NULL;
					}
				} else if (!strcmp("pango", service_name)) {
					const char *markup = mlt_properties_get( properties, "markup" );
					if (markup && !strcmp("INVALID", markup)) {
						service_name = NULL;
					}
				}
				if (service_name) {
					char *temp = calloc( 1, strlen( service_name ) + strlen( resource ) + 2 );
					strcat( temp, service_name );
					strcat( temp, ":" );
					strcat( temp, resource );
					producer = MLT_SERVICE( mlt_factory_producer( context->profile, NULL, temp ) );
					free( temp );
				}
			}
			else
			{
				producer = MLT_SERVICE( mlt_factory_producer( context->profile, NULL, service_name ) );
			}
		}

		// Just in case the plugin requested doesn't exist...
		if ( !producer && resource )
			producer = MLT_SERVICE( mlt_factory_producer( context->profile, NULL, resource ) );
		if ( !producer ) {
			mlt_log_error( NULL, "[producer_xml] failed to load producer \"%s\"\n", resource );
			producer = MLT_SERVICE( mlt_factory_producer( context->profile, NULL, "+INVALID.txt" ) );
			if (producer) {
				// Save the original mlt_service for the consumer to serialize it as original.
				mlt_properties_set_string( MLT_SERVICE_PROPERTIES(producer), "_xml_mlt_service",
					mlt_properties_get( properties, "mlt_service" ) );
			}
		}
		if ( !producer )
			producer = MLT_SERVICE( mlt_factory_producer( context->profile, NULL, "colour:red" ) );
		if ( !producer )
		{
			mlt_service_close( service );
			free( service );
			return;
		}

		// Track this producer
		track_service( context->destructors, producer, (mlt_destructor) mlt_producer_close );
		mlt_properties_set_lcnumeric( MLT_SERVICE_PROPERTIES( producer ), context->lc_numeric );
		if ( mlt_properties_get( MLT_SERVICE_PROPERTIES( producer ), "seekable" ) )
			context->seekable &= mlt_properties_get_int( MLT_SERVICE_PROPERTIES( producer ), "seekable" );

		// Propagate the properties
		qualify_property( context, properties, "resource" );
		qualify_property( context, properties, "luma" );
		qualify_property( context, properties, "luma.resource" );
		qualify_property( context, properties, "composite.luma" );
		qualify_property( context, properties, "producer.resource" );
		qualify_property( context, properties, "argument" ); // timewarp producer

		// Handle in/out properties separately
		mlt_position in = -1;
		mlt_position out = -1;

		// Get in
		if ( mlt_properties_get( properties, "in" ) )
			in = mlt_properties_get_position( properties, "in" );
		// Let Kino-SMIL clipBegin be a synonym for in
		else if ( mlt_properties_get( properties, "clipBegin" ) )
			in = mlt_properties_get_position( properties, "clipBegin" );
		// Get out
		if ( mlt_properties_get( properties, "out" ) )
			out = mlt_properties_get_position( properties, "out" );
		// Let Kino-SMIL clipEnd be a synonym for out
		else if ( mlt_properties_get( properties, "clipEnd" ) )
			out = mlt_properties_get_position( properties, "clipEnd" );
		// Remove in and out
		mlt_properties_set_string( properties, "in", NULL );
		mlt_properties_set_string( properties, "out", NULL );

		// Do not let XML overwrite these important properties set by mlt_factory.
		mlt_properties_set_string( properties, "mlt_type", NULL );
		mlt_properties_set_string( properties, "mlt_service", NULL );

		// Inherit the properties
		mlt_properties_inherit( MLT_SERVICE_PROPERTIES( producer ), properties );

		// Attach all filters from service onto producer
		attach_filters( producer, service );

		// Add the producer to the producer map
		if ( mlt_properties_get( properties, "id" ) != NULL )
			mlt_properties_set_data( context->producer_map, mlt_properties_get(properties, "id"), producer, 0, NULL, NULL );

		// See if the producer should be added to a playlist or multitrack
		if ( add_producer( context, producer, in, out ) == 0 )
		{
			// Otherwise, set in and out on...
			if ( in != -1 || out != -1 )
			{
				// Get the parent service
				enum service_type type;
				mlt_service parent = context_pop_service( context, &type );
				if ( parent != NULL )
				{
					// Get the parent properties
					properties = MLT_SERVICE_PROPERTIES( parent );

					char *resource = mlt_properties_get( properties, "resource" );

					// Put the parent producer back
					context_push_service( context, parent, type );

					// If the parent is a track or entry
					if ( resource && ( strcmp( resource, "<entry>" ) == 0 ) )
					{
						if ( in > -1 ) mlt_properties_set_position( properties, "in", in );
						if ( out > -1 ) mlt_properties_set_position( properties, "out", out );
					}
					else
					{
						// Otherwise, set in and out on producer directly
						mlt_producer_set_in_and_out( MLT_PRODUCER( producer ), in, out );
					}
				}
				else
				{
					// Otherwise, set in and out on producer directly
					mlt_producer_set_in_and_out( MLT_PRODUCER( producer ), in, out );
				}
			}

			// Push the producer onto the stack
			context_push_service( context, producer, mlt_producer_type );
		}
	}

	if ( service )
	{
		mlt_service_close( service );
		free( service );
	}
}

static void on_start_blank( deserialise_context context, const xmlChar *name, const xmlChar **atts)
{
	// Get the playlist from the stack
	enum service_type type;
	mlt_service service = context_pop_service( context, &type );

	if ( type == mlt_playlist_type && service != NULL )
	{
		// Look for the length attribute
		for ( ; atts != NULL && *atts != NULL; atts += 2 )
		{
			if ( xmlStrcmp( atts[0], _x("length") ) == 0 )
			{
				// Append a blank to the playlist
				mlt_playlist_blank_time( MLT_PLAYLIST( service ), _s(atts[1]) );
				break;
			}
		}

		// Push the playlist back onto the stack
		context_push_service( context, service, type );
	}
	else
	{
		mlt_log_error( NULL, "[producer_xml] blank without a playlist - a definite no no\n" );
	}
}

static void on_start_entry( deserialise_context context, const xmlChar *name, const xmlChar **atts)
{
	mlt_producer entry = NULL;
	mlt_properties temp = mlt_properties_new( );
	mlt_properties_set_data( temp, "_profile", context->profile, 0, NULL, NULL );
	mlt_properties_set_lcnumeric( temp, context->lc_numeric );

	for ( ; atts != NULL && *atts != NULL; atts += 2 )
	{
		mlt_properties_set_string( temp, (const char*) atts[0], atts[1] == NULL ? "" : (const char*) atts[1] );

		// Look for the producer attribute
		if ( xmlStrcmp( atts[ 0 ], _x("producer") ) == 0 )
		{
			mlt_producer producer = mlt_properties_get_data( context->producer_map, (const char*) atts[1], NULL );
			if ( producer !=  NULL )
				mlt_properties_set_data( temp, "producer", producer, 0, NULL, NULL );
		}
	}

	// If we have a valid entry
	if ( mlt_properties_get_data( temp, "producer", NULL ) != NULL )
	{
		mlt_playlist_clip_info info;
		enum service_type parent_type = mlt_invalid_type;
		mlt_service parent = context_pop_service( context, &parent_type );
		mlt_producer producer = mlt_properties_get_data( temp, "producer", NULL );

		if ( parent_type == mlt_playlist_type )
		{
			// Append the producer to the playlist
			mlt_position in = -1;
			mlt_position out = -1;
			if ( mlt_properties_get( temp, "in" ) )
				in = mlt_properties_get_position( temp, "in" );
			if ( mlt_properties_get( temp, "out" ) )
				out = mlt_properties_get_position( temp, "out" );
			mlt_playlist_append_io( MLT_PLAYLIST( parent ), producer, in, out );

			// Handle the repeat property
			if ( mlt_properties_get_int( temp, "repeat" ) > 0 )
			{
				mlt_playlist_repeat_clip( MLT_PLAYLIST( parent ),
										  mlt_playlist_count( MLT_PLAYLIST( parent ) ) - 1,
										  mlt_properties_get_int( temp, "repeat" ) );
			}

			mlt_playlist_get_clip_info( MLT_PLAYLIST( parent ), &info, mlt_playlist_count( MLT_PLAYLIST( parent ) ) - 1 );
			entry = info.cut;
		}
		else
		{
			mlt_log_error( NULL, "[producer_xml] Entry not part of a playlist...\n" );
		}

		context_push_service( context, parent, parent_type );
	}

	// Push the cut onto the stack
	context_push_service( context, MLT_PRODUCER_SERVICE( entry ), mlt_entry_type );

	mlt_properties_close( temp );
}

static void on_end_entry( deserialise_context context, const xmlChar *name )
{
	// Get the entry from the stack
	enum service_type entry_type = mlt_invalid_type;
	mlt_service entry = context_pop_service( context, &entry_type );

	if ( entry == NULL && entry_type != mlt_entry_type )
	{
		mlt_log_error( NULL, "[producer_xml] Invalid state at end of entry\n" );
	}
}

static void on_start_track( deserialise_context context, const xmlChar *name, const xmlChar **atts)
{
	// use a dummy service to hold properties to allow arbitrary nesting
	mlt_service service = calloc( 1, sizeof( struct mlt_service_s ) );
	mlt_service_init( service, NULL );

	// Push the dummy service onto the stack
	context_push_service( context, service, mlt_entry_type );

	mlt_properties_set_string( MLT_SERVICE_PROPERTIES( service ), "resource", "<track>" );

	for ( ; atts != NULL && *atts != NULL; atts += 2 )
	{
		mlt_properties_set_string( MLT_SERVICE_PROPERTIES( service ), (const char*) atts[0], atts[1] == NULL ? "" : (const char*) atts[1] );

		// Look for the producer attribute
		if ( xmlStrcmp( atts[ 0 ], _x("producer") ) == 0 )
		{
			mlt_producer producer = mlt_properties_get_data( context->producer_map, (const char*) atts[1], NULL );
			if ( producer !=  NULL )
				mlt_properties_set_data( MLT_SERVICE_PROPERTIES( service ), "producer", producer, 0, NULL, NULL );
		}
	}
}

static void on_end_track( deserialise_context context, const xmlChar *name )
{
	// Get the track from the stack
	enum service_type track_type;
	mlt_service track = context_pop_service( context, &track_type );

	if ( track != NULL && track_type == mlt_entry_type )
	{
		mlt_properties track_props = MLT_SERVICE_PROPERTIES( track );
		enum service_type parent_type = mlt_invalid_type;
		mlt_service parent = context_pop_service( context, &parent_type );
		mlt_multitrack multitrack = NULL;

		mlt_producer producer = mlt_properties_get_data( track_props, "producer", NULL );
		mlt_properties producer_props = MLT_PRODUCER_PROPERTIES( producer );

		if ( parent_type == mlt_tractor_type )
			multitrack = mlt_tractor_multitrack( MLT_TRACTOR( parent ) );
		else if ( parent_type == mlt_multitrack_type )
			multitrack = MLT_MULTITRACK( parent );
		else
			mlt_log_error( NULL, "[producer_xml] track contained in an invalid container\n" );

		if ( multitrack != NULL )
		{
			// Set producer i/o if specified
			if ( mlt_properties_get( track_props, "in" ) != NULL ||
				 mlt_properties_get( track_props, "out" ) != NULL )
			{
				mlt_position in = -1;
				mlt_position out = -1;
				if ( mlt_properties_get( track_props, "in" ) )
					in = mlt_properties_get_position( track_props, "in" );
				if ( mlt_properties_get( track_props, "out" ) )
					out = mlt_properties_get_position( track_props, "out" );
				mlt_producer cut = mlt_producer_cut( MLT_PRODUCER( producer ), in, out );
				mlt_multitrack_connect( multitrack, cut, mlt_multitrack_count( multitrack ) );
				mlt_properties_inherit( MLT_PRODUCER_PROPERTIES( cut ), track_props );
				track_props = MLT_PRODUCER_PROPERTIES( cut );
				mlt_producer_close( cut );
			}
			else
			{
				mlt_multitrack_connect( multitrack, producer, mlt_multitrack_count( multitrack ) );
			}

			// Set the hide state of the track producer
			char *hide_s = mlt_properties_get( track_props, "hide" );
			if ( hide_s != NULL )
			{
				if ( strcmp( hide_s, "video" ) == 0 )
					mlt_properties_set_int( producer_props, "hide", 1 );
				else if ( strcmp( hide_s, "audio" ) == 0 )
					mlt_properties_set_int( producer_props, "hide", 2 );
				else if ( strcmp( hide_s, "both" ) == 0 )
					mlt_properties_set_int( producer_props, "hide", 3 );
			}
		}

		if ( parent != NULL )
			context_push_service( context, parent, parent_type );
	}
	else
	{
		mlt_log_error( NULL, "[producer_xml] Invalid state at end of track\n" );
	}

	if ( track )
	{
		mlt_service_close( track );
		free( track );
	}
}

static void on_start_filter( deserialise_context context, const xmlChar *name, const xmlChar **atts)
{
	// use a dummy service to hold properties to allow arbitrary nesting
	mlt_service service = calloc( 1, sizeof( struct mlt_service_s ) );
	mlt_service_init( service, NULL );

	mlt_properties properties = MLT_SERVICE_PROPERTIES( service );

	context_push_service( context, service, mlt_dummy_filter_type );

	// Set the properties
	for ( ; atts != NULL && *atts != NULL; atts += 2 )
		mlt_properties_set_string( properties, (const char*) atts[0], (const char*) atts[1] );
}

static void on_end_filter( deserialise_context context, const xmlChar *name )
{
	enum service_type type;
	mlt_service service = context_pop_service( context, &type );
	mlt_properties properties = MLT_SERVICE_PROPERTIES( service );

	enum service_type parent_type = mlt_invalid_type;
	mlt_service parent = context_pop_service( context, &parent_type );

	if ( service != NULL && type == mlt_dummy_filter_type )
	{
		char *id = trim( mlt_properties_get( properties, "mlt_service" ) );
		mlt_service filter = MLT_SERVICE( mlt_factory_filter( context->profile, id, NULL ) );
		mlt_properties filter_props = MLT_SERVICE_PROPERTIES( filter );

		if ( !filter )
		{
			mlt_log_error( NULL, "[producer_xml] failed to load filter \"%s\"\n", id );
			if ( parent )
				context_push_service( context, parent, parent_type );
			mlt_service_close( service );
			free( service );
			return;
		}

		track_service( context->destructors, filter, (mlt_destructor) mlt_filter_close );
		mlt_properties_set_lcnumeric( MLT_SERVICE_PROPERTIES( filter ), context->lc_numeric );

		// Do not let XML overwrite these important properties set by mlt_factory.
		mlt_properties_set_string( properties, "mlt_type", NULL );
		mlt_properties_set_string( properties, "mlt_service", NULL );

		// Propagate the properties
		qualify_property( context, properties, "resource" );
		qualify_property( context, properties, "luma" );
		qualify_property( context, properties, "luma.resource" );
		qualify_property( context, properties, "composite.luma" );
		qualify_property( context, properties, "producer.resource" );
		qualify_property( context, properties, "filename" );
		qualify_property( context, properties, "av.file" );
		qualify_property( context, properties, "av.filename" );
		mlt_properties_inherit( filter_props, properties );

		// Attach all filters from service onto filter
		attach_filters( filter, service );

		// Associate the filter with the parent
		if ( parent != NULL )
		{
			if ( parent_type == mlt_tractor_type && mlt_properties_get( properties, "track" ) )
			{
				mlt_field field = mlt_tractor_field( MLT_TRACTOR( parent ) );
				mlt_field_plant_filter( field, MLT_FILTER( filter ), mlt_properties_get_int( properties, "track" ) );
				mlt_filter_set_in_and_out( MLT_FILTER( filter ),
										   mlt_properties_get_int( properties, "in" ),
										   mlt_properties_get_int( properties, "out" ) );
			}
			else
			{
				mlt_service_attach( parent, MLT_FILTER( filter ) );
			}

			// Put the parent back on the stack
			context_push_service( context, parent, parent_type );
		}
		else
		{
			mlt_log_error( NULL, "[producer_xml] filter closed with invalid parent...\n" );
		}
	}
	else
	{
		mlt_log_error( NULL, "[producer_xml] Invalid top of stack on filter close\n" );
	}

	if ( service )
	{
		mlt_service_close( service );
		free(service);
	}
}

static void on_start_transition( deserialise_context context, const xmlChar *name, const xmlChar **atts)
{
	// use a dummy service to hold properties to allow arbitrary nesting
	mlt_service service = calloc( 1, sizeof( struct mlt_service_s ) );
	mlt_service_init( service, NULL );

	mlt_properties properties = MLT_SERVICE_PROPERTIES( service );

	context_push_service( context, service, mlt_dummy_transition_type );

	// Set the properties
	for ( ; atts != NULL && *atts != NULL; atts += 2 )
		mlt_properties_set_string( properties, (const char*) atts[0], (const char*) atts[1] );
}

static void on_end_transition( deserialise_context context, const xmlChar *name )
{
	enum service_type type;
	mlt_service service = context_pop_service( context, &type );
	mlt_properties properties = MLT_SERVICE_PROPERTIES( service );

	enum service_type parent_type = mlt_invalid_type;
	mlt_service parent = context_pop_service( context, &parent_type );

	if ( service != NULL && type == mlt_dummy_transition_type )
	{
		char *id = trim( mlt_properties_get( properties, "mlt_service" ) );
		mlt_service effect = MLT_SERVICE( mlt_factory_transition( context->profile, id, NULL ) );
		mlt_properties effect_props = MLT_SERVICE_PROPERTIES( effect );

		if ( !effect )
		{
			mlt_log_error( NULL, "[producer_xml] failed to load transition \"%s\"\n", id );
			if ( parent )
				context_push_service( context, parent, parent_type );
			mlt_service_close( service );
			free( service );
			return;
		}
		track_service( context->destructors, effect, (mlt_destructor) mlt_transition_close );
		mlt_properties_set_lcnumeric( MLT_SERVICE_PROPERTIES( effect ), context->lc_numeric );

		// Do not let XML overwrite these important properties set by mlt_factory.
		mlt_properties_set_string( properties, "mlt_type", NULL );
		mlt_properties_set_string( properties, "mlt_service", NULL );

		// Propagate the properties
		qualify_property( context, properties, "resource" );
		qualify_property( context, properties, "luma" );
		qualify_property( context, properties, "luma.resource" );
		qualify_property( context, properties, "composite.luma" );
		qualify_property( context, properties, "producer.resource" );
		mlt_properties_inherit( effect_props, properties );

		// Attach all filters from service onto effect
		attach_filters( effect, service );

		// Associate the filter with the parent
		if ( parent != NULL )
		{
			if ( parent_type == mlt_tractor_type )
			{
				mlt_field field = mlt_tractor_field( MLT_TRACTOR( parent ) );
				mlt_field_plant_transition( field, MLT_TRANSITION( effect ),
											mlt_properties_get_int( properties, "a_track" ),
											mlt_properties_get_int( properties, "b_track" ) );
				mlt_transition_set_in_and_out( MLT_TRANSITION( effect ),
										   mlt_properties_get_int( properties, "in" ),
										   mlt_properties_get_int( properties, "out" ) );
			}
			else
			{
				mlt_log_warning( NULL, "[producer_xml] Misplaced transition - ignoring\n" );
			}

			// Put the parent back on the stack
			context_push_service( context, parent, parent_type );
		}
		else
		{
			mlt_log_error( NULL, "[producer_xml] transition closed with invalid parent...\n" );
		}

	}
	else
	{
		mlt_log_error( NULL, "[producer_xml] Invalid top of stack on transition close\n" );
	}

	if ( service )
	{
		mlt_service_close( service );
		free( service );
	}
}

static void on_start_consumer( deserialise_context context, const xmlChar *name, const xmlChar **atts)
{
	if ( context->pass == 1 )
	{
		mlt_properties properties = mlt_properties_new();

		mlt_properties_set_lcnumeric( properties, context->lc_numeric );
		context_push_service( context, (mlt_service) properties, mlt_dummy_consumer_type );

		// Set the properties from attributes
		for ( ; atts != NULL && *atts != NULL; atts += 2 )
			mlt_properties_set_string( properties, (const char*) atts[0], (const char*) atts[1] );
	}
}

static void set_preview_scale(mlt_profile *consumer_profile, mlt_profile *profile, double scale)
{
	*consumer_profile = mlt_profile_clone(*profile);
	if (*consumer_profile) {
		(*consumer_profile)->width *= scale;
		(*consumer_profile)->width -= (*consumer_profile)->width % 2;
		(*consumer_profile)->height *= scale;
		(*consumer_profile)->height -= (*consumer_profile)->height % 2;
	}
}

static void on_end_consumer( deserialise_context context, const xmlChar *name )
{
	if ( context->pass == 1 )
	{
		// Get the consumer from the stack
		enum service_type type;
		mlt_properties properties = (mlt_properties) context_pop_service( context, &type );

		if ( properties && type == mlt_dummy_consumer_type )
		{
			qualify_property( context, properties, "resource" );
			qualify_property( context, properties, "target" );
			char *resource = mlt_properties_get( properties, "resource" );

			if ( context->multi_consumer > 1 || context->qglsl || mlt_properties_get_int( context->params, "multi" ) )
			{
				// Instantiate the multi consumer
				if ( !context->consumer )
				{
					if ( context->qglsl )
						context->consumer = context->qglsl;
					else
						context->consumer = mlt_factory_consumer( context->profile, "multi", NULL );
					if ( context->consumer )
					{
						// Track this consumer
						track_service( context->destructors, MLT_CONSUMER_SERVICE(context->consumer), (mlt_destructor) mlt_consumer_close );
						mlt_properties_set_lcnumeric( MLT_CONSUMER_PROPERTIES(context->consumer), context->lc_numeric );
					}
				}
				if ( context->consumer )
				{
					// Set this properties object on multi consumer
					mlt_properties consumer_properties = MLT_CONSUMER_PROPERTIES(context->consumer);
					char key[20];
					snprintf( key, sizeof(key), "%d", context->consumer_count++ );
					mlt_properties_inc_ref( properties );
					mlt_properties_set_data( consumer_properties, key, properties, 0,
						(mlt_destructor) mlt_properties_close, NULL );

					// Pass in / out if provided
					mlt_properties_pass_list( consumer_properties, properties, "in, out" );

					// Pass along quality and performance properties to the multi consumer and its render thread(s).
					if ( !context->qglsl )
					{
						mlt_properties_pass_list( consumer_properties, properties,
							"real_time, deinterlace_method, rescale, progressive, top_field_first, channels, channel_layout" );

						// We only really know how to optimize real_time for the avformat consumer.
						const char *service_name = mlt_properties_get( properties, "mlt_service" );
						if ( service_name && !strcmp( "avformat", service_name ) )
							mlt_properties_set_int( properties, "real_time", -1 );
					}
				}
			}
			else
			{
				double scale = mlt_properties_get_double(properties, "scale");
				if (scale > 0.0) {
					set_preview_scale(&context->consumer_profile, &context->profile, scale);
				}
				// Instantiate the consumer
				char *id = trim( mlt_properties_get( properties, "mlt_service" ) );
				mlt_profile profile = context->consumer_profile? context->consumer_profile : context->profile;
				context->consumer = mlt_factory_consumer( profile, id, resource );
				if ( context->consumer )
				{
					// Track this consumer
					track_service( context->destructors, MLT_CONSUMER_SERVICE(context->consumer), (mlt_destructor) mlt_consumer_close );
					mlt_properties_set_lcnumeric( MLT_CONSUMER_PROPERTIES(context->consumer), context->lc_numeric );
					if (context->consumer_profile) {
						mlt_properties_set_data(MLT_CONSUMER_PROPERTIES(context->consumer),
							"_profile", context->consumer_profile, sizeof(*context->consumer_profile),
							(mlt_destructor) mlt_profile_close, NULL);
					}

					// Do not let XML overwrite these important properties set by mlt_factory.
					mlt_properties_set_string( properties, "mlt_type", NULL );
					mlt_properties_set_string( properties, "mlt_service", NULL );

					// Inherit the properties
					mlt_properties_inherit( MLT_CONSUMER_PROPERTIES(context->consumer), properties );
				}
			}
		}
		// Close the dummy
		if ( properties )
			mlt_properties_close( properties );
	}
}

static void on_start_property( deserialise_context context, const xmlChar *name, const xmlChar **atts)
{
	enum service_type type;
	mlt_service service = context_pop_service( context, &type );
	mlt_properties properties = MLT_SERVICE_PROPERTIES( service );
	const char *value = NULL;

	if ( service != NULL )
	{
		// Set the properties
		for ( ; atts != NULL && *atts != NULL; atts += 2 )
		{
			if ( xmlStrcmp( atts[ 0 ], _x("name") ) == 0 )
				context->property = strdup( _s(atts[ 1 ]) );
			else if ( xmlStrcmp( atts[ 0 ], _x("value") ) == 0 )
				value = _s(atts[ 1 ]);
		}

		if ( context->property != NULL )
			mlt_properties_set_string( properties, context->property, value == NULL ? "" : value );

		// Tell parser to collect any further nodes for serialisation
		context->is_value = 1;

		context_push_service( context, service, type );
	}
	else
	{
		mlt_log_error( NULL, "[producer_xml] Property without a service '%s'?\n", ( const char * )name );
	}
}

static void on_end_property( deserialise_context context, const xmlChar *name )
{
	enum service_type type;
	mlt_service service = context_pop_service( context, &type );
	mlt_properties properties = MLT_SERVICE_PROPERTIES( service );

	if ( service != NULL )
	{
		// Tell parser to stop building a tree
		context->is_value = 0;

		// See if there is a xml tree for the value
		if ( context->property != NULL && context->value_doc != NULL )
		{
			xmlChar *value;
			int size;

			// Serialise the tree to get value
			xmlDocDumpMemory( context->value_doc, &value, &size );
			mlt_properties_set_string( properties, context->property, _s(value) );
#ifdef _WIN32
			xmlFreeFunc xmlFree = NULL;
			xmlMemGet( &xmlFree, NULL, NULL, NULL);
#endif
			xmlFree( value );
			xmlFreeDoc( context->value_doc );
			context->value_doc = NULL;
		}

		// Close this property handling
		free( context->property );
		context->property = NULL;

		context_push_service( context, service, type );
	}
	else
	{
		mlt_log_error( NULL, "[producer_xml] Property without a service '%s'??\n", (const char *)name );
	}
}

static void on_start_element( void *ctx, const xmlChar *name, const xmlChar **atts)
{
	struct _xmlParserCtxt *xmlcontext = ( struct _xmlParserCtxt* )ctx;
	deserialise_context context = ( deserialise_context )( xmlcontext->_private );

	if ( context->pass == 0 )
	{
		if ( xmlStrcmp( name, _x("mlt") ) == 0 ||
		     xmlStrcmp( name, _x("profile") ) == 0 ||
		     xmlStrcmp( name, _x("profileinfo") ) == 0 )
			on_start_profile( context, name, atts );
		if ( xmlStrcmp( name, _x("consumer") ) == 0 )
			context->multi_consumer++;

		// Check for a service beginning with glsl. or movit.
		for ( ; atts != NULL && *atts != NULL; atts += 2 ) {
			if ( !xmlStrncmp( atts[1], _x("glsl."), 5 ) || !xmlStrncmp( atts[1], _x("movit."), 6 ) ) {
				mlt_properties_set_int( context->params, "qglsl", 1 );
				break;
			}
		}
		return;
	}
	mlt_deque_push_back_int( context->stack_branch, mlt_deque_pop_back_int( context->stack_branch ) + 1 );
	mlt_deque_push_back_int( context->stack_branch, 0 );

	// Build a tree from nodes within a property value
	if ( context->is_value == 1 && context->pass == 1 )
	{
		xmlNodePtr node = xmlNewNode( NULL, name );

		if ( context->value_doc == NULL )
		{
			// Start a new tree
			context->value_doc = xmlNewDoc( _x("1.0") );
			xmlDocSetRootElement( context->value_doc, node );
		}
		else
		{
			// Append child to tree
			xmlAddChild( mlt_deque_peek_back( context->stack_node ), node );
		}
		context_push_node( context, node );

		// Set the attributes
		for ( ; atts != NULL && *atts != NULL; atts += 2 )
			xmlSetProp( node, atts[ 0 ], atts[ 1 ] );
	}
	else if ( xmlStrcmp( name, _x("tractor") ) == 0 )
		on_start_tractor( context, name, atts );
	else if ( xmlStrcmp( name, _x("multitrack") ) == 0 )
		on_start_multitrack( context, name, atts );
	else if ( xmlStrcmp( name, _x("playlist") ) == 0 || xmlStrcmp( name, _x("seq") ) == 0 || xmlStrcmp( name, _x("smil") ) == 0 )
		on_start_playlist( context, name, atts );
	else if ( xmlStrcmp( name, _x("producer") ) == 0 || xmlStrcmp( name, _x("video") ) == 0 )
		on_start_producer( context, name, atts );
	else if ( xmlStrcmp( name, _x("blank") ) == 0 )
		on_start_blank( context, name, atts );
	else if ( xmlStrcmp( name, _x("entry") ) == 0 )
		on_start_entry( context, name, atts );
	else if ( xmlStrcmp( name, _x("track") ) == 0 )
		on_start_track( context, name, atts );
	else if ( xmlStrcmp( name, _x("filter") ) == 0 )
		on_start_filter( context, name, atts );
	else if ( xmlStrcmp( name, _x("transition") ) == 0 )
		on_start_transition( context, name, atts );
	else if ( xmlStrcmp( name, _x("property") ) == 0 )
		on_start_property( context, name, atts );
	else if ( xmlStrcmp( name, _x("consumer") ) == 0 )
		on_start_consumer( context, name, atts );
	else if ( xmlStrcmp( name, _x("westley") ) == 0 || xmlStrcmp( name, _x("mlt") ) == 0 )
	{
		for ( ; atts != NULL && *atts != NULL; atts += 2 )
		{
			if ( xmlStrcmp( atts[0], _x("LC_NUMERIC") ) )
				mlt_properties_set_string( context->producer_map, _s( atts[0] ), _s(atts[1] ) );
			else if ( !context->lc_numeric )
				context->lc_numeric = strdup( _s( atts[1] ) );
		}
	}
}

static void on_end_element( void *ctx, const xmlChar *name )
{
	struct _xmlParserCtxt *xmlcontext = ( struct _xmlParserCtxt* )ctx;
	deserialise_context context = ( deserialise_context )( xmlcontext->_private );

	if ( context->is_value == 1 && context->pass == 1 && xmlStrcmp( name, _x("property") ) != 0 )
		context_pop_node( context );
	else if ( xmlStrcmp( name, _x("multitrack") ) == 0 )
		on_end_multitrack( context, name );
	else if ( xmlStrcmp( name, _x("playlist") ) == 0 || xmlStrcmp( name, _x("seq") ) == 0 || xmlStrcmp( name, _x("smil") ) == 0 )
		on_end_playlist( context, name );
	else if ( xmlStrcmp( name, _x("track") ) == 0 )
		on_end_track( context, name );
	else if ( xmlStrcmp( name, _x("entry") ) == 0 )
		on_end_entry( context, name );
	else if ( xmlStrcmp( name, _x("tractor") ) == 0 )
		on_end_tractor( context, name );
	else if ( xmlStrcmp( name, _x("property") ) == 0 )
		on_end_property( context, name );
	else if ( xmlStrcmp( name, _x("producer") ) == 0 || xmlStrcmp( name, _x("video") ) == 0 )
		on_end_producer( context, name );
	else if ( xmlStrcmp( name, _x("filter") ) == 0 )
		on_end_filter( context, name );
	else if ( xmlStrcmp( name, _x("transition") ) == 0 )
		on_end_transition( context, name );
	else if ( xmlStrcmp( name, _x("consumer") ) == 0 )
		on_end_consumer( context, name );

	mlt_deque_pop_back_int( context->stack_branch );
}

static void on_characters( void *ctx, const xmlChar *ch, int len )
{
	struct _xmlParserCtxt *xmlcontext = ( struct _xmlParserCtxt* )ctx;
	deserialise_context context = ( deserialise_context )( xmlcontext->_private );
	char *value = calloc( 1, len + 1 );
	enum service_type type;
	mlt_service service = context_pop_service( context, &type );
	mlt_properties properties = MLT_SERVICE_PROPERTIES( service );

	if ( service != NULL )
		context_push_service( context, service, type );

	value[ len ] = 0;
	strncpy( value, (const char*) ch, len );

	if ( mlt_deque_count( context->stack_node ) )
		xmlNodeAddContent( mlt_deque_peek_back( context->stack_node ), ( xmlChar* )value );

	// libxml2 generates an on_characters immediately after a get_entity within
	// an element value, and we ignore it because it is called again during
	// actual substitution.
	else if ( context->property != NULL && context->entity_is_replace == 0 )
	{
		char *s = mlt_properties_get( properties, context->property );
		if ( s != NULL )
		{
			// Append new text to existing content
			char *new = calloc( 1, strlen( s ) + len + 1 );
			strcat( new, s );
			strcat( new, value );
			mlt_properties_set_string( properties, context->property, new );
			free( new );
		}
		else
			mlt_properties_set_string( properties, context->property, value );
	}
	context->entity_is_replace = 0;

	// Check for a service beginning with glsl. or movit.
	if ( !strncmp( value, "glsl.", 5 ) || !strncmp( value, "movit.", 6 ) )
		mlt_properties_set_int( context->params, "qglsl", 1 );

	free( value);
}

/** Convert parameters parsed from resource into entity declarations.
*/
static void params_to_entities( deserialise_context context )
{
	if ( context->params != NULL )
	{
		int i;

		// Add our params as entity declarations
		for ( i = 0; i < mlt_properties_count( context->params ); i++ )
		{
			xmlChar *name = ( xmlChar* )mlt_properties_get_name( context->params, i );
			xmlAddDocEntity( context->entity_doc, name, XML_INTERNAL_GENERAL_ENTITY,
				context->publicId, context->systemId, ( xmlChar* )mlt_properties_get( context->params, _s(name) ) );
		}

		// Flag completion
		mlt_properties_close( context->params );
		context->params = NULL;
	}
}

// The following 3 facilitate entity substitution in the SAX parser
static void on_internal_subset( void *ctx, const xmlChar* name,
	const xmlChar* publicId, const xmlChar* systemId )
{
	struct _xmlParserCtxt *xmlcontext = ( struct _xmlParserCtxt* )ctx;
	deserialise_context context = ( deserialise_context )( xmlcontext->_private );

	context->publicId = publicId;
	context->systemId = systemId;
	xmlCreateIntSubset( context->entity_doc, name, publicId, systemId );

	// Override default entities with our parameters
	params_to_entities( context );
}

// TODO: Check this with Dan... I think this is for parameterisation
// but it's breaking standard escaped entities (like &lt; etc).
static void on_entity_declaration( void *ctx, const xmlChar* name, int type,
	const xmlChar* publicId, const xmlChar* systemId, xmlChar* content)
{
	struct _xmlParserCtxt *xmlcontext = ( struct _xmlParserCtxt* )ctx;
	deserialise_context context = ( deserialise_context )( xmlcontext->_private );

	xmlAddDocEntity( context->entity_doc, name, type, publicId, systemId, content );
}

// TODO: Check this functionality (see on_entity_declaration)
static xmlEntityPtr on_get_entity( void *ctx, const xmlChar* name )
{
	struct _xmlParserCtxt *xmlcontext = ( struct _xmlParserCtxt* )ctx;
	deserialise_context context = ( deserialise_context )( xmlcontext->_private );
	xmlEntityPtr e = NULL;

	// Setup for entity declarations if not ready
	if ( xmlGetIntSubset( context->entity_doc ) == NULL )
	{
		xmlCreateIntSubset( context->entity_doc, _x("mlt"), _x(""), _x("") );
		context->publicId = _x("");
		context->systemId = _x("");
	}

	// Add our parameters if not already
	params_to_entities( context );

	e = xmlGetPredefinedEntity( name );

	// Send signal to on_characters that an entity substitutin is pending
	if ( e == NULL )
	{
		e = xmlGetDocEntity( context->entity_doc, name );
		if ( e != NULL )
			context->entity_is_replace = 1;
	}

	return e;
}

static void	on_error( void * ctx, const char * msg, ... )
{
	struct _xmlError* err_ptr = xmlCtxtGetLastError( ctx );

	switch( err_ptr->level )
	{
	case XML_ERR_WARNING:
		mlt_log_warning( NULL, "[producer_xml] parse warning: %s\trow: %d\tcol: %d\n",
				         err_ptr->message, err_ptr->line, err_ptr->int2 );
		break;
	case XML_ERR_ERROR:
		mlt_log_error( NULL, "[producer_xml] parse error: %s\trow: %d\tcol: %d\n",
				       err_ptr->message, err_ptr->line, err_ptr->int2 );
		break;
	default:
	case XML_ERR_FATAL:
		mlt_log_fatal( NULL, "[producer_xml] parse fatal: %s\trow: %d\tcol: %d\n",
				       err_ptr->message, err_ptr->line, err_ptr->int2 );
		break;
	}
}

/** Convert a hexadecimal character to its value.
*/
static int tohex( char p )
{
	return isdigit( p ) ? p - '0' : tolower( p ) - 'a' + 10;
}

/** Decode a url-encoded string containing hexadecimal character sequences.
*/
static char *url_decode( char *dest, char *src )
{
	char *p = dest;

	while ( *src )
	{
		if ( *src == '%' )
		{
			*p ++ = ( tohex( *( src + 1 ) ) << 4 ) | tohex( *( src + 2 ) );
			src += 3;
		}
		else
		{
			*p ++ = *src ++;
		}
	}

	*p = *src;
	return dest;
}

/** Extract the filename from a URL attaching parameters to a properties list.
*/
static void parse_url( mlt_properties properties, char *url )
{
	int i;
	int n = strlen( url );
	char *name = NULL;
	char *value = NULL;
	int is_query = 0;

	for ( i = 0; i < n; i++ )
	{
		switch ( url[ i ] )
		{
			case '?':
				url[ i++ ] = '\0';
				name = &url[ i ];
				is_query = 1;
				break;

			case ':':
#ifdef _WIN32
				if ( url[i + 1] != '/' && url[i + 1] != '\\' )
#endif
			case '=':
				if ( is_query )
				{
					url[ i++ ] = '\0';
					value = &url[ i ];
				}
				break;

			case '&':
				if ( is_query )
				{
					url[ i++ ] = '\0';
					if ( name != NULL && value != NULL )
						mlt_properties_set_string( properties, name, value );
					name = &url[ i ];
					value = NULL;
				}
				break;
		}
	}
	if ( name != NULL && value != NULL )
		mlt_properties_set_string( properties, name, value );
}

// Quick workaround to avoid unnecessary libxml2 warnings
static int file_exists( char *name )
{
	int exists = 0;
	if ( name != NULL )
	{
		FILE *f = mlt_fopen( name, "r" );
		exists = f != NULL;
		if ( exists ) fclose( f );
	}
	return exists;
}

// This function will add remaining services in the context service stack marked
// with a "xml_retain" property to a property named "xml_retain" on the returned
// service. The property is a mlt_properties data property.

static void retain_services( struct deserialise_context_s *context, mlt_service service )
{
	mlt_properties retain_list = mlt_properties_new();
	enum service_type type;
	mlt_service retain_service = context_pop_service( context, &type );

	while ( retain_service )
	{
		mlt_properties retain_properties = MLT_SERVICE_PROPERTIES( retain_service );

		if ( mlt_properties_get_int( retain_properties, "xml_retain" ) )
		{
			// Remove the retained service from the destructors list.
			int i;
			for ( i = mlt_properties_count( context->destructors ) - 1; i >= 1; i -- )
			{
				const char *name = mlt_properties_get_name( context->destructors, i );
				if ( mlt_properties_get_data_at( context->destructors, i, NULL ) == retain_service )
				{
					mlt_properties_set_data( context->destructors, name, retain_service, 0, NULL, NULL );
					break;
				}
			}
			const char *name = mlt_properties_get( retain_properties, "id" );
			if ( name )
				mlt_properties_set_data( retain_list, name, retain_service, 0,
					(mlt_destructor) mlt_service_close, NULL );
		}
		retain_service = context_pop_service( context, &type );
	}
	if ( mlt_properties_count( retain_list ) > 0 )
	{
		mlt_properties_set_data( MLT_SERVICE_PROPERTIES(service), "xml_retain", retain_list, 0,
			(mlt_destructor) mlt_properties_close, NULL );
	}
	else
	{
		mlt_properties_close( retain_list );
	}
}

static deserialise_context context_new( mlt_profile profile )
{
	deserialise_context context = calloc( 1, sizeof( struct deserialise_context_s ) );
	if ( context )
	{
		context->producer_map = mlt_properties_new();
		context->destructors = mlt_properties_new();
		context->params = mlt_properties_new();
		context->profile = profile;
		context->seekable = 1;
		context->stack_service = mlt_deque_init();
		context->stack_types = mlt_deque_init();
		context->stack_node = mlt_deque_init();
		context->stack_branch = mlt_deque_init();
		mlt_deque_push_back_int( context->stack_branch, 0 );
	}
	return context;
}

static void context_close( deserialise_context context )
{
	mlt_properties_close( context->producer_map );
	mlt_properties_close( context->destructors );
	mlt_properties_close( context->params );
	mlt_deque_close( context->stack_service );
	mlt_deque_close( context->stack_types );
	mlt_deque_close( context->stack_node );
	mlt_deque_close( context->stack_branch );
	xmlFreeDoc( context->entity_doc );
	free( context->lc_numeric );
	free( context );
}

mlt_producer producer_xml_init( mlt_profile profile, mlt_service_type servtype, const char *id, char *data )
{
	xmlSAXHandler *sax, *sax_orig;
	deserialise_context context;
	mlt_properties properties = NULL;
	int i = 0;
	struct _xmlParserCtxt *xmlcontext;
	int well_formed = 0;
	char *filename = NULL;
	int is_filename = strcmp( id, "xml-string" );

	// Strip file:// prefix
	if ( data && strlen( data ) >= 7 && strncmp( data, "file://", 7 ) == 0 )
		data += 7;

	if ( data == NULL || !strcmp( data, "" ) )
		return NULL;

	context = context_new( profile );
	if ( context == NULL )
		return NULL;

	// Decode URL and parse parameters
	mlt_properties_set_string( context->producer_map, "root", "" );
	if ( is_filename )
	{
		mlt_properties_set_string( context->params, "_mlt_xml_resource", data );
		filename = mlt_properties_get( context->params, "_mlt_xml_resource" );
		parse_url( context->params, url_decode( filename, data ) );

		// We need the directory prefix which was used for the xml
		if ( strchr( filename, '/' ) || strchr( filename, '\\' ) )
		{
			char *root = NULL;
			mlt_properties_set_string( context->producer_map, "root", filename );
			root = mlt_properties_get( context->producer_map, "root" );
			if ( strchr( root, '/') )
				*( strrchr( root, '/' ) ) = '\0';
			else if ( strchr( root, '\\') )
				*( strrchr( root, '\\' ) ) = '\0';

			// If we don't have an absolute path here, we're heading for disaster...
			if ( root[ 0 ] != '/' && !strchr( root, ':' ) )
			{
				char *cwd = getcwd( NULL, 0 );
				char *real = malloc( strlen( cwd ) + strlen( root ) + 2 );
				sprintf( real, "%s/%s", cwd, root );
				mlt_properties_set_string( context->producer_map, "root", real );
				free( real );
				free( cwd );
			}
		}

		if ( !file_exists( filename ) )
		{
			// Try the un-converted text encoding as a fallback.
			// Fixes launching melt as child process from Shotcut on Windows
			// when there are extended characters in the path.
			filename = mlt_properties_get( context->params, "_mlt_xml_resource" );
		}

		if ( !file_exists( filename ) )
		{
			context_close( context );
			return NULL;
		}
	}

	// We need to track the number of registered filters
	mlt_properties_set_int( context->destructors, "registered", 0 );

	// Setup SAX callbacks for first pass
	sax = calloc( 1, sizeof( xmlSAXHandler ) );
	sax->startElement = on_start_element;
	sax->characters = on_characters;
	sax->warning = on_error;
	sax->error = on_error;
	sax->fatalError = on_error;

	// Setup libxml2 SAX parsing
	xmlInitParser();
	xmlSubstituteEntitiesDefault( 1 );
	// This is used to facilitate entity substitution in the SAX parser
	context->entity_doc = xmlNewDoc( _x("1.0") );
	if ( is_filename )
		xmlcontext = xmlCreateFileParserCtxt( filename );
	else
		xmlcontext = xmlCreateMemoryParserCtxt( data, strlen( data ) );

	// Invalid context - clean up and return NULL
	if ( xmlcontext == NULL )
	{
		context_close( context );
		free( sax );
		return NULL;
	}

	// Parse
	sax_orig = xmlcontext->sax;
	xmlcontext->sax = sax;
	xmlcontext->_private = ( void* )context;
	xmlParseDocument( xmlcontext );
	well_formed = xmlcontext->wellFormed;

	// Cleanup after parsing
	xmlcontext->sax = sax_orig;
	xmlcontext->_private = NULL;
	if ( xmlcontext->myDoc )
		xmlFreeDoc( xmlcontext->myDoc );
	xmlFreeParserCtxt( xmlcontext );

	// Bad xml - clean up and return NULL
	if ( !well_formed )
	{
		context_close( context );
		free( sax );
		return NULL;
	}

	// Setup the second pass
	context->pass ++;
	if ( is_filename )
		xmlcontext = xmlCreateFileParserCtxt( filename );
	else
		xmlcontext = xmlCreateMemoryParserCtxt( data, strlen( data ) );

	// Invalid context - clean up and return NULL
	if ( xmlcontext == NULL )
	{
		context_close( context );
		free( sax );
		return NULL;
	}

	// Reset the stack.
	mlt_deque_close( context->stack_service );
	mlt_deque_close( context->stack_types );
	mlt_deque_close( context->stack_node );
	context->stack_service = mlt_deque_init();
	context->stack_types = mlt_deque_init();
	context->stack_node = mlt_deque_init();

	// Create the qglsl consumer now, if requested, so that glsl.manager
	// may exist when trying to load glsl. or movit. services.
	// The "if requested" part can come from query string qglsl=1 or when
	// a service beginning with glsl. or movit. appears in the XML.
	if ( mlt_properties_get_int( context->params, "qglsl" ) && strcmp( id, "xml-nogl" )
		// Only if glslManager does not yet exist.
		&& !mlt_properties_get_data( mlt_global_properties(), "glslManager", NULL ) )
		context->qglsl = mlt_factory_consumer( profile, "qglsl", NULL );

	// Setup SAX callbacks for second pass
	sax->endElement = on_end_element;
	sax->cdataBlock = on_characters;
	sax->internalSubset = on_internal_subset;
	sax->entityDecl = on_entity_declaration;
	sax->getEntity = on_get_entity;

	// Parse
	sax_orig = xmlcontext->sax;
	xmlcontext->sax = sax;
	xmlcontext->_private = ( void* )context;
	xmlParseDocument( xmlcontext );
	well_formed = xmlcontext->wellFormed;

	// Cleanup after parsing
	xmlFreeDoc( context->entity_doc );
	context->entity_doc = NULL;
	free( sax );
	xmlMemoryDump( ); // for debugging
	xmlcontext->sax = sax_orig;
	xmlcontext->_private = NULL;
	if ( xmlcontext->myDoc )
		xmlFreeDoc( xmlcontext->myDoc );
	xmlFreeParserCtxt( xmlcontext );

	// Get the last producer on the stack
	enum service_type type;
	mlt_service service = context_pop_service( context, &type );
	if ( well_formed && service != NULL )
	{
		// Verify it is a producer service (mlt_type="mlt_producer")
		// (producer, playlist, multitrack)
		char *type = mlt_properties_get( MLT_SERVICE_PROPERTIES( service ), "mlt_type" );
		if ( type == NULL || ( strcmp( type, "mlt_producer" ) != 0 && strcmp( type, "producer" ) != 0 ) )
			service = NULL;
	}

#ifdef DEBUG
	xmlDocPtr doc = xml_make_doc( service );
	xmlDocFormatDump( stdout, doc, 1 );
	xmlFreeDoc( doc );
	service = NULL;
#endif

	if ( well_formed && service != NULL )
	{
		char *title = mlt_properties_get( context->producer_map, "title" );

		// Need the complete producer list for various reasons
		properties = context->destructors;

		// Now make sure we don't have a reference to the service in the properties
		for ( i = mlt_properties_count( properties ) - 1; i >= 1; i -- )
		{
			char *name = mlt_properties_get_name( properties, i );
			if ( mlt_properties_get_data_at( properties, i, NULL ) == service )
			{
				mlt_properties_set_data( properties, name, service, 0, NULL, NULL );
				break;
			}
		}

		// We are done referencing destructor property list
		// Set this var to service properties for convenience
		properties = MLT_SERVICE_PROPERTIES( service );

		// Assign the title
		mlt_properties_set_string( properties, "title", title );

		// Optimise for overlapping producers
		mlt_producer_optimise( MLT_PRODUCER( service ) );

		// Handle deep copies
		if ( getenv( "MLT_XML_DEEP" ) == NULL )
		{
			// Now assign additional properties
			if ( is_filename && (
				mlt_service_identify( service ) == tractor_type ||
				mlt_service_identify( service ) == playlist_type ||
				mlt_service_identify( service ) == multitrack_type ) )
			{
				mlt_properties_set_int( properties, "_original_type",
					mlt_service_identify( service ) );
				mlt_properties_set_string( properties, "_original_resource",
					mlt_properties_get( properties, "resource" ) );
				mlt_properties_set_string( properties, "resource", data );
			}

			// This tells consumer_xml not to deep copy
			mlt_properties_set_string( properties, "xml", "was here" );
		}
		else
		{
			// Allow the project to be edited
			mlt_properties_set_string( properties, "_xml", "was here" );
			mlt_properties_set_int( properties, "_mlt_service_hidden", 1 );
		}

		// Make consumer available
		mlt_properties_inc_ref( MLT_CONSUMER_PROPERTIES( context->consumer ) );
		mlt_properties_set_data( properties, "consumer", context->consumer, 0,
			(mlt_destructor) mlt_consumer_close, NULL );

		mlt_properties_set_int( properties, "seekable", context->seekable );

		retain_services( context, service );
	}
	else
	{
		// Return null if not well formed
		service = NULL;
	}

	// Clean up
	if ( context->qglsl && context->consumer != context->qglsl )
		mlt_consumer_close( context->qglsl );
	context_close( context );

	return MLT_PRODUCER( service );
}