src/framework/mlt_properties.c

[melted] / src / framework / mlt_properties.c

/*
 * mlt_properties.c -- base properties class
 * Copyright (C) 2003-2004 Ushodaya Enterprises Limited
 * Author: Charles Yates <charles.yates@pandora.be>
 *
 * 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 "config.h"
#include "mlt_properties.h"
#include "mlt_property.h"

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

/* ---------------- // Private Implementation // ---------------- */

/** Private implementation of the property list.
*/

typedef struct
{
        int hash[ 199 ];
        char **name;
        mlt_property *value;
        int count;
        int size;
        mlt_properties mirror;
        int ref_count;
}
property_list;

/** Memory leak checks.
*/

//#define _MLT_PROPERTY_CHECKS_ 2

#ifdef _MLT_PROPERTY_CHECKS_
static int properties_created = 0;
static int properties_destroyed = 0;
#endif

/** Basic implementation.
*/

int mlt_properties_init( mlt_properties this, void *child )
{
        if ( this != NULL )
        {
#ifdef _MLT_PROPERTY_CHECKS_
                // Increment number of properties created
                properties_created ++;
#endif

                // NULL all methods
                memset( this, 0, sizeof( struct mlt_properties_s ) );

                // Assign the child of the object
                this->child = child;

                // Allocate the local structure
                this->local = calloc( sizeof( property_list ), 1 );

                // Increment the ref count
                ( ( property_list * )this->local )->ref_count = 1;
        }

        // Check that initialisation was successful
        return this != NULL && this->local == NULL;
}

/** Constructor for stand alone object.
*/

mlt_properties mlt_properties_new( )
{
        // Construct a standalone properties object
        mlt_properties this = calloc( sizeof( struct mlt_properties_s ), 1 );

        // Initialise this
        mlt_properties_init( this, NULL );

        // Return the pointer
        return this;
}

/** Load properties from a file.
*/

mlt_properties mlt_properties_load( const char *filename )
{
        // Construct a standalone properties object
        mlt_properties this = mlt_properties_new( );

        if ( this != NULL )
        {
                // Open the file
                FILE *file = fopen( filename, "r" );

                // Load contents of file
                if ( file != NULL )
                {
                        // Temp string
                        char temp[ 1024 ];
                        char last[ 1024 ] = "";

                        // Read each string from the file
                        while( fgets( temp, 1024, file ) )
                        {
                                // Chomp the string
                                temp[ strlen( temp ) - 1 ] = '\0';

                                // Check if the line starts with a .
                                if ( temp[ 0 ] == '.' )
                                {
                                        char temp2[ 1024 ];
                                        sprintf( temp2, "%s%s", last, temp );
                                        strcpy( temp, temp2 );
                                }
                                else if ( strchr( temp, '=' ) )
                                {
                                        strcpy( last, temp );
                                        *( strchr( last, '=' ) ) = '\0';
                                }

                                // Parse and set the property
                                if ( strcmp( temp, "" ) && temp[ 0 ] != '#' )
                                        mlt_properties_parse( this, temp );
                        }

                        // Close the file
                        fclose( file );
                }
        }

        // Return the pointer
        return this;
}

static inline int generate_hash( const char *name )
{
        int hash = 0;
        int i = 1;
        while ( *name )
                hash = ( hash + ( i ++ * ( *name ++ & 31 ) ) ) % 199;
        return hash;
}

/** Special case - when a container (such as fezzik) is protecting another 
        producer, we need to ensure that properties are passed through to the
        real producer.
*/

static inline void mlt_properties_do_mirror( mlt_properties this, const char *name )
{
        property_list *list = this->local;
        if ( list->mirror != NULL ) 
        {
                char *value = mlt_properties_get( this, name );
                if ( value != NULL )
                        mlt_properties_set( list->mirror, name, value );
        }
}

/** Maintain ref count to allow multiple uses of an mlt object.
*/

int mlt_properties_inc_ref( mlt_properties this )
{
        if ( this != NULL )
        {
                property_list *list = this->local;
                return ++ list->ref_count;
        }
        return 0;
}

/** Maintain ref count to allow multiple uses of an mlt object.
*/

int mlt_properties_dec_ref( mlt_properties this )
{
        if ( this != NULL )
        {
                property_list *list = this->local;
                return -- list->ref_count;
        }
        return 0;
}

/** Return the ref count of this object.
*/

int mlt_properties_ref_count( mlt_properties this )
{
        if ( this != NULL )
        {
                property_list *list = this->local;
                return list->ref_count;
        }
        return 0;
}

/** Mirror properties set on 'this' to 'that'.
*/

void mlt_properties_mirror( mlt_properties this, mlt_properties that )
{
        property_list *list = this->local;
        list->mirror = that;
}

/** Inherit all serialisable properties from that into this.
*/

int mlt_properties_inherit( mlt_properties this, mlt_properties that )
{
        int count = mlt_properties_count( that );
        int i = 0;
        for ( i = 0; i < count; i ++ )
        {
                char *value = mlt_properties_get_value( that, i );
                if ( value != NULL )
                {
                        char *name = mlt_properties_get_name( that, i );
                        mlt_properties_set( this, name, value );
                }
        }
        return 0;
}

/** Pass all properties from 'that' that match the prefix to 'this' (excluding the prefix).
*/

int mlt_properties_pass( mlt_properties this, mlt_properties that, const char *prefix )
{
        int count = mlt_properties_count( that );
        int length = strlen( prefix );
        int i = 0;
        for ( i = 0; i < count; i ++ )
        {
                char *name = mlt_properties_get_name( that, i );
                if ( !strncmp( name, prefix, length ) )
                {
                        char *value = mlt_properties_get_value( that, i );
                        if ( value != NULL )
                                mlt_properties_set( this, name + length, value );
                }
        }
        return 0;
}


/** Locate a property by name
*/

static inline mlt_property mlt_properties_find( mlt_properties this, const char *name )
{
        property_list *list = this->local;
        mlt_property value = NULL;
        int key = generate_hash( name );
        int i = list->hash[ key ] - 1;

        if ( i >= 0 )
        {
                // Check if we're hashed
                if ( list->count > 0 &&
                        name[ 0 ] == list->name[ i ][ 0 ] && 
                        !strcmp( list->name[ i ], name ) )
                        value = list->value[ i ];

                // Locate the item 
                for ( i = list->count - 1; value == NULL && i >= 0; i -- )
                        if ( name[ 0 ] == list->name[ i ][ 0 ] && !strcmp( list->name[ i ], name ) )
                                value = list->value[ i ];
        }

        return value;
}

/** Add a new property.
*/

static mlt_property mlt_properties_add( mlt_properties this, const char *name )
{
        property_list *list = this->local;
        int key = generate_hash( name );

        // Check that we have space and resize if necessary
        if ( list->count == list->size )
        {
                list->size += 50;
                list->name = realloc( list->name, list->size * sizeof( const char * ) );
                list->value = realloc( list->value, list->size * sizeof( mlt_property ) );
        }

        // Assign name/value pair
        list->name[ list->count ] = strdup( name );
        list->value[ list->count ] = mlt_property_init( );

        // Assign to hash table
        if ( list->hash[ key ] == 0 )
                list->hash[ key ] = list->count + 1;

        // Return and increment count accordingly
        return list->value[ list->count ++ ];
}

/** Fetch a property by name - this includes add if not found.
*/

static mlt_property mlt_properties_fetch( mlt_properties this, const char *name )
{
        // Try to find an existing property first
        mlt_property property = mlt_properties_find( this, name );

        // If it wasn't found, create one
        if ( property == NULL )
                property = mlt_properties_add( this, name );

        // Return the property
        return property;
}

/** Pass property 'name' from 'that' to 'this' 
* Who to blame: Zach <zachary.drew@gmail.com>
*/

void mlt_properties_pass_property( mlt_properties this, mlt_properties that, const char *name )
{
        // Make sure the source property isn't null.
        mlt_property that_prop = mlt_properties_find( that, name );
        if( that_prop == NULL )
                return;

        mlt_property_pass( mlt_properties_fetch( this, name ), that_prop );
}

/** Pass all properties from 'that' to 'this' as found in comma seperated 'list'.
* Who to blame: Zach <zachary.drew@gmail.com>
*/

int mlt_properties_pass_list( mlt_properties this, mlt_properties that, const char *list )
{
        char *props = strdup( list );
        char *ptr = props;
        char *delim = " ,\t\n"; // Any combination of spaces, commas, tabs, and newlines
        int count, done = 0;

        while( !done )
        {
                count = strcspn( ptr, delim );

                if( ptr[count] == '\0' )
                        done = 1;
                else
                        ptr[count] = '\0';      // Make it a real string

                mlt_properties_pass_property( this, that, ptr );

                ptr += count + 1;
                ptr += strspn( ptr, delim );
        }

        free( props );

        return 0;
}


/** Set the property.
*/

int mlt_properties_set( mlt_properties this, const char *name, const char *value )
{
        int error = 1;

        // Fetch the property to work with
        mlt_property property = mlt_properties_fetch( this, name );

        // Set it if not NULL
        if ( property == NULL )
        {
                fprintf( stderr, "Whoops - %s not found (should never occur)\n", name );
        }
        else if ( value == NULL )
        {
                error = mlt_property_set_string( property, value );
                mlt_properties_do_mirror( this, name );
        }
        else if ( *value != '@' )
        {
                error = mlt_property_set_string( property, value );
                mlt_properties_do_mirror( this, name );
        }
        else if ( value[ 0 ] == '@' )
        {
                int total = 0;
                int current = 0;
                char id[ 255 ];
                char op = '+';

                value ++;

                while ( *value != '\0' )
                {
                        int length = strcspn( value, "+-*/" );

                        // Get the identifier
                        strncpy( id, value, length );
                        id[ length ] = '\0';
                        value += length;

                        // Determine the value
                        if ( isdigit( id[ 0 ] ) )
                                current = atof( id );
                        else
                                current = mlt_properties_get_int( this, id );

                        // Apply the operation
                        switch( op )
                        {
                                case '+':
                                        total += current;
                                        break;
                                case '-':
                                        total -= current;
                                        break;
                                case '*':
                                        total *= current;
                                        break;
                                case '/':
                                        total /= current;
                                        break;
                        }

                        // Get the next op
                        op = *value != '\0' ? *value ++ : ' ';
                }

                error = mlt_property_set_int( property, total );
                mlt_properties_do_mirror( this, name );
        }

        mlt_events_fire( this, "property-changed", name, NULL );

        return error;
}

/** Set or default the property.
*/

int mlt_properties_set_or_default( mlt_properties this, const char *name, const char *value, const char *def )
{
        return mlt_properties_set( this, name, value == NULL ? def : value );
}

/** Get a string value by name.
*/

char *mlt_properties_get( mlt_properties this, const char *name )
{
        mlt_property value = mlt_properties_find( this, name );
        return value == NULL ? NULL : mlt_property_get_string( value );
}

/** Get a name by index.
*/

char *mlt_properties_get_name( mlt_properties this, int index )
{
        property_list *list = this->local;
        if ( index >= 0 && index < list->count )
                return list->name[ index ];
        return NULL;
}

/** Get a string value by index.
*/

char *mlt_properties_get_value( mlt_properties this, int index )
{
        property_list *list = this->local;
        if ( index >= 0 && index < list->count )
                return mlt_property_get_string( list->value[ index ] );
        return NULL;
}

/** Get a data value by index.
*/

void *mlt_properties_get_data_at( mlt_properties this, int index, int *size )
{
        property_list *list = this->local;
        if ( index >= 0 && index < list->count )
                return mlt_property_get_data( list->value[ index ], size );
        return NULL;
}

/** Return the number of items in the list.
*/

int mlt_properties_count( mlt_properties this )
{
        property_list *list = this->local;
        return list->count;
}

/** Set a value by parsing a name=value string
*/

int mlt_properties_parse( mlt_properties this, const char *namevalue )
{
        char *name = strdup( namevalue );
        char *value = NULL;
        int error = 0;
        char *ptr = strchr( name, '=' );

        if ( ptr )
        {
                *( ptr ++ ) = '\0';

                if ( *ptr != '\"' )
                {
                        value = strdup( ptr );
                }
                else
                {
                        ptr ++;
                        value = strdup( ptr );
                        if ( value != NULL && value[ strlen( value ) - 1 ] == '\"' )
                                value[ strlen( value ) - 1 ] = '\0';
                }
        }
        else
        {
                value = strdup( "" );
        }

        error = mlt_properties_set( this, name, value );

        free( name );
        free( value );

        return error;
}

/** Get a value associated to the name.
*/

int mlt_properties_get_int( mlt_properties this, const char *name )
{
        mlt_property value = mlt_properties_find( this, name );
        return value == NULL ? 0 : mlt_property_get_int( value );
}

/** Set a value associated to the name.
*/

int mlt_properties_set_int( mlt_properties this, const char *name, int value )
{
        int error = 1;

        // Fetch the property to work with
        mlt_property property = mlt_properties_fetch( this, name );

        // Set it if not NULL
        if ( property != NULL )
        {
                error = mlt_property_set_int( property, value );
                mlt_properties_do_mirror( this, name );
        }

        mlt_events_fire( this, "property-changed", name, NULL );

        return error;
}

/** Get a value associated to the name.
*/

int64_t mlt_properties_get_int64( mlt_properties this, const char *name )
{
        mlt_property value = mlt_properties_find( this, name );
        return value == NULL ? 0 : mlt_property_get_int64( value );
}

/** Set a value associated to the name.
*/

int mlt_properties_set_int64( mlt_properties this, const char *name, int64_t value )
{
        int error = 1;

        // Fetch the property to work with
        mlt_property property = mlt_properties_fetch( this, name );

        // Set it if not NULL
        if ( property != NULL )
        {
                error = mlt_property_set_int64( property, value );
                mlt_properties_do_mirror( this, name );
        }

        mlt_events_fire( this, "property-changed", name, NULL );

        return error;
}

/** Get a value associated to the name.
*/

double mlt_properties_get_double( mlt_properties this, const char *name )
{
        mlt_property value = mlt_properties_find( this, name );
        return value == NULL ? 0 : mlt_property_get_double( value );
}

/** Set a value associated to the name.
*/

int mlt_properties_set_double( mlt_properties this, const char *name, double value )
{
        int error = 1;

        // Fetch the property to work with
        mlt_property property = mlt_properties_fetch( this, name );

        // Set it if not NULL
        if ( property != NULL )
        {
                error = mlt_property_set_double( property, value );
                mlt_properties_do_mirror( this, name );
        }

        mlt_events_fire( this, "property-changed", name, NULL );

        return error;
}

/** Get a value associated to the name.
*/

mlt_position mlt_properties_get_position( mlt_properties this, const char *name )
{
        mlt_property value = mlt_properties_find( this, name );
        return value == NULL ? 0 : mlt_property_get_position( value );
}

/** Set a value associated to the name.
*/

int mlt_properties_set_position( mlt_properties this, const char *name, mlt_position value )
{
        int error = 1;

        // Fetch the property to work with
        mlt_property property = mlt_properties_fetch( this, name );

        // Set it if not NULL
        if ( property != NULL )
        {
                error = mlt_property_set_position( property, value );
                mlt_properties_do_mirror( this, name );
        }

        mlt_events_fire( this, "property-changed", name, NULL );

        return error;
}

/** Get a value associated to the name.
*/

void *mlt_properties_get_data( mlt_properties this, const char *name, int *length )
{
        mlt_property value = mlt_properties_find( this, name );
        return value == NULL ? NULL : mlt_property_get_data( value, length );
}

/** Set a value associated to the name.
*/

int mlt_properties_set_data( mlt_properties this, const char *name, void *value, int length, mlt_destructor destroy, mlt_serialiser serialise )
{
        int error = 1;

        // Fetch the property to work with
        mlt_property property = mlt_properties_fetch( this, name );

        // Set it if not NULL
        if ( property != NULL )
                error = mlt_property_set_data( property, value, length, destroy, serialise );

        mlt_events_fire( this, "property-changed", name, NULL );

        return error;
}

/** Rename a property.
*/

int mlt_properties_rename( mlt_properties this, const char *source, const char *dest )
{
        mlt_property value = mlt_properties_find( this, dest );

        if ( value == NULL )
        {
                property_list *list = this->local;
                int i = 0;

                // Locate the item 
                for ( i = 0; i < list->count; i ++ )
                {
                        if ( !strcmp( list->name[ i ], source ) )
                        {
                                free( list->name[ i ] );
                                list->name[ i ] = strdup( dest );
                                list->hash[ generate_hash( dest ) ] = i + 1;
                                break;
                        }
                }
        }

        return value != NULL;
}

/** Dump the properties.
*/

void mlt_properties_dump( mlt_properties this, FILE *output )
{
        property_list *list = this->local;
        int i = 0;
        for ( i = 0; i < list->count; i ++ )
                if ( mlt_properties_get( this, list->name[ i ] ) != NULL )
                        fprintf( output, "%s=%s\n", list->name[ i ], mlt_properties_get( this, list->name[ i ] ) );
}

void mlt_properties_debug( mlt_properties this, const char *title, FILE *output )
{
        fprintf( output, "%s: ", title );
        if ( this != NULL )
        {
                property_list *list = this->local;
                int i = 0;
                fprintf( output, "[ ref=%d", list->ref_count );
                for ( i = 0; i < list->count; i ++ )
                        if ( mlt_properties_get( this, list->name[ i ] ) != NULL )
                                fprintf( output, ", %s=%s", list->name[ i ], mlt_properties_get( this, list->name[ i ] ) );
                        else
                                fprintf( output, ", %s=%p", list->name[ i ], mlt_properties_get_data( this, list->name[ i ], NULL ) );
                fprintf( output, " ]" );
        }
        fprintf( output, "\n" );
}

/** Close the list.
*/

void mlt_properties_close( mlt_properties this )
{
        if ( this != NULL && mlt_properties_dec_ref( this ) <= 0 )
        {
                if ( this->close != NULL )
                {
                        this->close( this->close_object );
                }
                else
                {
                        property_list *list = this->local;
                        int index = 0;

#if _MLT_PROPERTY_CHECKS_ == 1
                        // Show debug info
                        mlt_properties_debug( this, "Closing", stderr );
#endif

#ifdef _MLT_PROPERTY_CHECKS_
                        // Increment destroyed count
                        properties_destroyed ++;

                        // Show current stats - these should match when the app is closed
                        fprintf( stderr, "Created %d, destroyed %d\n", properties_created, properties_destroyed );
#endif

                        // Clean up names and values
                        for ( index = list->count - 1; index >= 0; index -- )
                        {
                                free( list->name[ index ] );
                                mlt_property_close( list->value[ index ] );
                        }
        
                        // Clear up the list
                        free( list->name );
                        free( list->value );
                        free( list );
        
                        // Free this now if this has no child
                        if ( this->child == NULL )
                                free( this );
                }
        }
}