Detailed Description

A lightweight RDF model library.

Sord stores RDF (subject object predicate context) quads, where the context may be omitted (to represent triples in the default graph).

Typedefs
typedef struct SordWorldImpl	SordWorld

typedef struct SordModelImpl	SordModel

typedef struct SordInserterImpl	SordInserter

typedef struct SordIterImpl	SordIter

typedef struct SordNodeImpl	SordNode

typedef const SordNode *	SordQuad [4]

Enumerations
enum	SordQuadIndex { SORD_SUBJECT = 0, SORD_PREDICATE = 1, SORD_OBJECT = 2, SORD_GRAPH = 3 }

enum	SordNodeType { SORD_URI = 1, SORD_BLANK = 2, SORD_LITERAL = 3 }

enum	SordIndexOption { SORD_SPO = 1, SORD_SOP = 1 << 1, SORD_OPS = 1 << 2, SORD_OSP = 1 << 3, SORD_PSO = 1 << 4, SORD_POS = 1 << 5 }

World
SordWorld *	sord_world_new (void)

void	sord_world_free (SordWorld *world)

void	sord_world_set_error_sink (SordWorld world, SerdErrorSink error_sink, void handle)

Node
SordNode *	sord_new_uri (SordWorld world, const uint8_t uri)

SordNode *	sord_new_relative_uri (SordWorld world, const uint8_t str, const uint8_t *base_uri)

SordNode *	sord_new_blank (SordWorld world, const uint8_t str)

SordNode *	sord_new_literal (SordWorld world, SordNode datatype, const uint8_t str, const char lang)

SordNode *	sord_node_copy (const SordNode *node)

void	sord_node_free (SordWorld world, SordNode node)

SordNodeType	sord_node_get_type (const SordNode *node)

const uint8_t *	sord_node_get_string (const SordNode *node)

const uint8_t *	sord_node_get_string_counted (const SordNode node, size_t len)

const char *	sord_node_get_language (const SordNode *node)

SordNode *	sord_node_get_datatype (const SordNode *node)

SerdNodeFlags	sord_node_get_flags (const SordNode *node)

bool	sord_node_is_inline_object (const SordNode *node)

bool	sord_node_equals (const SordNode a, const SordNode b)

const SerdNode *	sord_node_to_serd_node (const SordNode *node)

SordNode *	sord_node_from_serd_node (SordWorld world, SerdEnv env, const SerdNode node, const SerdNode datatype, const SerdNode *lang)

Model
SordModel *	sord_new (SordWorld *world, unsigned indices, bool graphs)

void	sord_free (SordModel *model)

SordWorld *	sord_get_world (SordModel *model)

size_t	sord_num_nodes (const SordWorld *world)

size_t	sord_num_quads (const SordModel *model)

SordIter *	sord_begin (const SordModel *model)

SordIter *	sord_find (SordModel *model, const SordQuad pat)

SordIter *	sord_search (SordModel model, const SordNode s, const SordNode p, const SordNode o, const SordNode *g)

SordNode *	sord_get (SordModel model, const SordNode s, const SordNode p, const SordNode o, const SordNode *g)

bool	sord_ask (SordModel model, const SordNode s, const SordNode p, const SordNode o, const SordNode *g)

uint64_t	sord_count (SordModel model, const SordNode s, const SordNode p, const SordNode o, const SordNode *g)

bool	sord_contains (SordModel *model, const SordQuad pat)

bool	sord_add (SordModel *model, const SordQuad quad)

void	sord_remove (SordModel *model, const SordQuad quad)

Inserter
SordInserter *	sord_inserter_new (SordModel model, SerdEnv env)

void	sord_inserter_free (SordInserter *inserter)

SerdStatus	sord_inserter_set_base_uri (SordInserter inserter, const SerdNode uri)

SerdStatus	sord_inserter_set_prefix (SordInserter inserter, const SerdNode name, const SerdNode *uri)

SerdStatus	sord_inserter_write_statement (SordInserter inserter, SerdStatementFlags flags, const SerdNode graph, const SerdNode subject, const SerdNode predicate, const SerdNode object, const SerdNode object_datatype, const SerdNode *object_lang)

Iteration
void	sord_iter_get (const SordIter *iter, SordQuad quad)

const SordNode *	sord_iter_get_node (const SordIter *iter, SordQuadIndex index)

const SordModel *	sord_iter_get_model (SordIter *iter)

bool	sord_iter_next (SordIter *iter)

bool	sord_iter_end (const SordIter *iter)

void	sord_iter_free (SordIter *iter)

Utilities
bool	sord_quad_match (const SordQuad x, const SordQuad y)

Serialisation
SerdReader *	sord_new_reader (SordModel model, SerdEnv env, SerdSyntax syntax, SordNode *graph)

bool	sord_write (SordModel model, SerdWriter writer, SordNode *graph)

bool	sord_write_iter (SordIter iter, SerdWriter writer)

Typedef Documentation

typedef struct SordWorldImpl SordWorld

Sord World.

The World represents all library state, including interned strings.

typedef struct SordModelImpl SordModel

Sord Model.

A model is an indexed set of Quads (i.e. it can contain several RDF graphs). It may be searched using various patterns depending on which indices are enabled.

typedef struct SordInserterImpl SordInserter

Model Inserter.

An inserter is used for writing statements to a model using the Serd sink interface. This makes it simple to write to a model directly using a SerdReader, or any other code that writes statements to a SerdStatementSink.

typedef struct SordIterImpl SordIter

Model Iterator.

typedef struct SordNodeImpl SordNode

RDF Node.

A Node is a component of a Quad. Nodes may be URIs, blank nodes, or (in the case of quad objects only) string literals. Literal nodes may have an associate language or datatype (but not both).

typedef const SordNode* SordQuad[4]

Quad of nodes (a statement), or a quad pattern.

Nodes are ordered (S P O G). The ID of the default graph is 0.

Enumeration Type Documentation

enum SordQuadIndex

Index into a SordQuad.

Enumerator
SORD_SUBJECT	Subject.
SORD_PREDICATE	Predicate (a.k.a. "key")
SORD_OBJECT	Object (a.k.a. "value")
SORD_GRAPH	Graph (a.k.a. "context")

enum SordNodeType

Type of a node.

Enumerator
SORD_URI	URI.
SORD_BLANK	Blank node identifier.
SORD_LITERAL	Literal (string with optional lang or datatype)

enum SordIndexOption

Indexing option.

Enumerator
SORD_SPO	Subject, Predicate, Object.
SORD_SOP	Subject, Object, Predicate.
SORD_OPS	Object, Predicate, Subject.
SORD_OSP	Object, Subject, Predicate.
SORD_PSO	Predicate, Subject, Object.
SORD_POS	Predicate, Object, Subject.

Function Documentation

SordWorld* sord_world_new ( void )

Create a new Sord World.

It is safe to use multiple worlds in one process, though no data (e.g. nodes) can be shared between worlds, and this should be avoided if possible for performance reasons.

void sord_world_free ( SordWorld * world )

Free world.

void sord_world_set_error_sink	(	SordWorld *	world,
		SerdErrorSink	error_sink,
		void *	handle
	)

Set a function to be called when errors occur.

The error_sink will be called with handle as its first argument. If no error function is set, errors are printed to stderr.

SordNode* sord_new_uri	(	SordWorld *	world,
		const uint8_t *	uri
	)

Get a URI node from a string.

Note this function measures str, which is a common bottleneck. Use sord_node_from_serd_node instead if str is already measured.

SordNode* sord_new_relative_uri	(	SordWorld *	world,
		const uint8_t *	str,
		const uint8_t *	base_uri
	)

Get a URI node from a relative URI string.

SordNode* sord_new_blank	(	SordWorld *	world,
		const uint8_t *	str
	)

Get a blank node from a string.

Note this function measures str, which is a common bottleneck. Use sord_node_from_serd_node instead if str is already measured.

SordNode* sord_new_literal	(	SordWorld *	world,
		SordNode *	datatype,
		const uint8_t *	str,
		const char *	lang
	)

Get a literal node from a string.

Note this function measures str, which is a common bottleneck. Use sord_node_from_serd_node instead if str is already measured.

SordNode* sord_node_copy ( const SordNode * node )

Copy a node (obtain a reference).

Node that since nodes are interned and reference counted, this does not actually create a deep copy of node.

void sord_node_free	(	SordWorld *	world,
		SordNode *	node
	)

Free a node (drop a reference).

SordNodeType sord_node_get_type ( const SordNode * node )

Return the type of a node (SORD_URI, SORD_BLANK, or SORD_LITERAL).

const uint8_t* sord_node_get_string ( const SordNode * node )

Return the string value of a node.

const uint8_t* sord_node_get_string_counted	(	const SordNode *	node,
		size_t *	len
	)

Return the string value of a node, and set len to its length.

const char* sord_node_get_language ( const SordNode * node )

Return the language of a literal node (or NULL).

SordNode* sord_node_get_datatype ( const SordNode * node )

Return the datatype URI of a literal node (or NULL).

SerdNodeFlags sord_node_get_flags ( const SordNode * node )

Return the flags (string attributes) of a node.

bool sord_node_is_inline_object ( const SordNode * node )

Return true iff node can be serialised as an inline object.

More specifically, this returns true iff the node is the object field of exactly one statement, and therefore can be inlined since it needn't be referred to by name.

bool sord_node_equals	(	const SordNode *	a,
		const SordNode *	b
	)

Return true iff a is equal to b.

Note this is much faster than comparing the node's strings.

const SerdNode* sord_node_to_serd_node ( const SordNode * node )

Return a SordNode as a SerdNode.

The returned node is shared and must not be freed or modified.

SordNode* sord_node_from_serd_node	(	SordWorld *	world,
		SerdEnv *	env,
		const SerdNode *	node,
		const SerdNode *	datatype,
		const SerdNode *	lang
	)

Create a new SordNode from a SerdNode.

The returned node must be freed using sord_node_free.

SordModel* sord_new	(	SordWorld *	world,
		unsigned	indices,
		bool	graphs
	)

Create a new model.

Parameters

world	The world in which to make this model.
indices	SordIndexOption flags (e.g. SORD_SPO\|SORD_OPS). Be sure to enable an index where the most significant node(s) are not variables in your queries (e.g. to make (? P O) queries, enable either SORD_OPS or SORD_POS).
graphs	If true, store (and index) graph contexts.

void sord_free ( SordModel * model )

Close and free model.

SordWorld* sord_get_world ( SordModel * model )

Get the world associated with model.

size_t sord_num_nodes ( const SordWorld * world )

Return the number of nodes stored in world.

Nodes are included in this count iff they are a part of a quad in world.

size_t sord_num_quads ( const SordModel * model )

Return the number of quads stored in model.

SordIter* sord_begin ( const SordModel * model )

Return an iterator to the start of model.

SordIter* sord_find	(	SordModel *	model,
		const SordQuad	pat
	)

Search for statements by a quad pattern.

Returns: an iterator to the first match, or NULL if no matches found.

SordIter* sord_search	(	SordModel *	model,
		const SordNode *	s,
		const SordNode *	p,
		const SordNode *	o,
		const SordNode *	g
	)

Search for statements by nodes.

Returns: an iterator to the first match, or NULL if no matches found.

SordNode* sord_get	(	SordModel *	model,
		const SordNode *	s,
		const SordNode *	p,
		const SordNode *	o,
		const SordNode *	g
	)

Search for a single node that matches a pattern.

Exactly one of s, p, o must be NULL. This function is mainly useful for predicates that only have one value. The returned node must be freed using sord_node_free.

Returns: the first matching node, or NULL if no matches are found.

bool sord_ask	(	SordModel *	model,
		const SordNode *	s,
		const SordNode *	p,
		const SordNode *	o,
		const SordNode *	g
	)

Return true iff a statement exists.

uint64_t sord_count	(	SordModel *	model,
		const SordNode *	s,
		const SordNode *	p,
		const SordNode *	o,
		const SordNode *	g
	)

Return the number of matching statements.

bool sord_contains	(	SordModel *	model,
		const SordQuad	pat
	)

Check if model contains a triple pattern.

bool sord_add	(	SordModel *	model,
		const SordQuad	quad
	)

Add a quad to a model.

void sord_remove	(	SordModel *	model,
		const SordQuad	quad
	)

Remove a quad from a model.

Note that is it illegal to remove while iterating over model.

SordInserter* sord_inserter_new	(	SordModel *	model,
		SerdEnv *	env
	)

Create an inserter for writing statements to a model.

void sord_inserter_free ( SordInserter * inserter )

Free an inserter.

SerdStatus sord_inserter_set_base_uri	(	SordInserter *	inserter,
		const SerdNode *	uri
	)

Set the current base URI for writing to the model.

Note this function can be safely casted to SerdBaseSink.

SerdStatus sord_inserter_set_prefix	(	SordInserter *	inserter,
		const SerdNode *	name,
		const SerdNode *	uri
	)

Set a namespace prefix for writing to the model.

Note this function can be safely casted to SerdPrefixSink.

SerdStatus sord_inserter_write_statement	(	SordInserter *	inserter,
		SerdStatementFlags	flags,
		const SerdNode *	graph,
		const SerdNode *	subject,
		const SerdNode *	predicate,
		const SerdNode *	object,
		const SerdNode *	object_datatype,
		const SerdNode *	object_lang
	)

Write a statement to the model.

Note this function can be safely casted to SerdStatementSink.

void sord_iter_get	(	const SordIter *	iter,
		SordQuad	quad
	)

Set quad to the quad pointed to by iter.

const SordNode* sord_iter_get_node	(	const SordIter *	iter,
		SordQuadIndex	index
	)

Return a field of the quad pointed to by iter.

const SordModel* sord_iter_get_model ( SordIter * iter )

Return the store pointed to by iter.

bool sord_iter_next ( SordIter * iter )

Increment iter to point to the next statement.

bool sord_iter_end ( const SordIter * iter )

Return true iff iter is at the end of its range.

void sord_iter_free ( SordIter * iter )

Free iter.

bool sord_quad_match	(	const SordQuad	x,
		const SordQuad	y
	)

Match two quads (using ID comparison only).

This function is a straightforward and fast equivalence match with wildcard support (ID 0 is a wildcard). It does not actually read node data.

Returns: true iff x and y match.

SerdReader* sord_new_reader	(	SordModel *	model,
		SerdEnv *	env,
		SerdSyntax	syntax,
		SordNode *	graph
	)

Return a reader that will read into model.

bool sord_write	(	SordModel *	model,
		SerdWriter *	writer,
		SordNode *	graph
	)

Write a model to a writer.

bool sord_write_iter	(	SordIter *	iter,
		SerdWriter *	writer
	)

Write a range to a writer.

This increments iter to its end, then frees it.

Detailed Description

Typedefs

Enumerations

World

Node

Model

Inserter

Iteration

Utilities

Serialisation

Typedef Documentation

Enumeration Type Documentation

Function Documentation