pattern.h File Reference

pattern expression handling More...

Typedefs
typedef struct _xmlPattern	xmlPattern
	A compiled (XPath based) pattern to select nodes.

Enumerations
enum	xmlPatternFlags
	Internal type. More...

Functions
void	xmlFreePattern (xmlPattern *comp)
	Free up the memory allocated by comp
void	xmlFreePatternList (xmlPattern *comp)
	Free up the memory allocated by all the elements of comp
xmlPattern *	xmlPatterncompile (const xmlChar *pattern, xmlDict *dict, int flags, const xmlChar **namespaces)
	Compile a pattern.
int	xmlPatternCompileSafe (const xmlChar *pattern, xmlDict *dict, int flags, const xmlChar **namespaces, xmlPattern **patternOut)
	Compile a pattern.
int	xmlPatternMatch (xmlPattern *comp, xmlNode *node)
	Test whether the node matches the pattern.
int	xmlPatternStreamable (xmlPattern *comp)
	Check if the pattern is streamable i.e.
int	xmlPatternMaxDepth (xmlPattern *comp)
	Check the maximum depth reachable by a pattern.
int	xmlPatternMinDepth (xmlPattern *comp)
	Check the minimum depth reachable by a pattern, 0 mean the / or .
int	xmlPatternFromRoot (xmlPattern *comp)
	Check if the pattern must be looked at from the root.
xmlStreamCtxt *	xmlPatternGetStreamCtxt (xmlPattern *comp)
	Get a streaming context for that pattern Use xmlFreeStreamCtxt to free the context.
void	xmlFreeStreamCtxt (xmlStreamCtxt *stream)
	Free the stream context.
int	xmlStreamPushNode (xmlStreamCtxt *stream, const xmlChar *name, const xmlChar *ns, int nodeType)
	Push new data onto the stream.
int	xmlStreamPush (xmlStreamCtxt *stream, const xmlChar *name, const xmlChar *ns)
	Push new data onto the stream.
int	xmlStreamPushAttr (xmlStreamCtxt *stream, const xmlChar *name, const xmlChar *ns)
	Push new attribute data onto the stream.
int	xmlStreamPop (xmlStreamCtxt *stream)
	push one level from the stream.
int	xmlStreamWantsAnyNode (xmlStreamCtxt *stream)
	Query if the streaming pattern additionally needs to be fed with text-, cdata-section-, comment- and processing-instruction-nodes.

Detailed Description

pattern expression handling

allows to compile and test pattern expressions for nodes either in a tree or based on a parser state.

Copyright

See Copyright for the status of this software.

Author

Daniel Veillard

Enumeration Type Documentation

xmlPatternFlags

enum xmlPatternFlags

Internal type.

This is the set of options affecting the behaviour of pattern matching with this module.

Function Documentation

xmlFreePattern()

void xmlFreePattern

(

xmlPattern *

comp

)

Free up the memory allocated by comp

Parameters

comp	an XSLT comp

xmlFreePatternList()

void xmlFreePatternList

(

xmlPattern *

comp

)

Free up the memory allocated by all the elements of comp

Parameters

comp	an XSLT comp list

xmlFreeStreamCtxt()

void xmlFreeStreamCtxt

(

xmlStreamCtxt *

stream

)

Free the stream context.

Parameters

stream

the stream context

xmlPatterncompile()

xmlPattern * xmlPatterncompile	(	const xmlChar *	pattern,
		xmlDict *	dict,
		int	flags,
		const xmlChar **	namespaces
	)

Compile a pattern.

Parameters

pattern	the pattern to compile
dict	an optional dictionary for interned strings
flags	compilation flags, see xmlPatternFlags
namespaces	the prefix definitions, array of [URI, prefix] or NULL

Returns

the compiled form of the pattern or NULL in case of error

xmlPatternCompileSafe()

int xmlPatternCompileSafe	(	const xmlChar *	pattern,
		xmlDict *	dict,
		int	flags,
		const xmlChar **	namespaces,
		xmlPattern **	patternOut
	)

Compile a pattern.

Since

2.13.0

Parameters

pattern	the pattern to compile
dict	an optional dictionary for interned strings
flags	compilation flags, see xmlPatternFlags
namespaces	the prefix definitions, array of [URI, prefix] or NULL
patternOut	output pattern

Returns

0 on success, 1 on error, -1 if a memory allocation failed.

xmlPatternFromRoot()

int xmlPatternFromRoot

(

xmlPattern *

comp

)

Check if the pattern must be looked at from the root.

Parameters

comp	the precompiled pattern

Returns

1 if true, 0 if false and -1 in case of error

xmlPatternGetStreamCtxt()

xmlStreamCtxt * xmlPatternGetStreamCtxt

(

xmlPattern *

comp

)

Get a streaming context for that pattern Use xmlFreeStreamCtxt to free the context.

Parameters

comp	the precompiled pattern

Returns

a pointer to the context or NULL in case of failure

xmlPatternMatch()

int xmlPatternMatch	(	xmlPattern *	comp,
		xmlNode *	node
	)

Test whether the node matches the pattern.

Parameters

comp	the precompiled pattern
node	a node

Returns

1 if it matches, 0 if it doesn't and -1 in case of failure

xmlPatternMaxDepth()

int xmlPatternMaxDepth

(

xmlPattern *

comp

)

Check the maximum depth reachable by a pattern.

Parameters

comp	the precompiled pattern

Returns

-2 if no limit (using //), otherwise the depth, and -1 in case of error

xmlPatternMinDepth()

int xmlPatternMinDepth

(

xmlPattern *

comp

)

Check the minimum depth reachable by a pattern, 0 mean the / or .

are part of the set.

Parameters

comp	the precompiled pattern

Returns

-1 in case of error otherwise the depth,

xmlPatternStreamable()

int xmlPatternStreamable

(

xmlPattern *

comp

)

Check if the pattern is streamable i.e.

xmlPatternGetStreamCtxt should work.

Parameters

comp	the precompiled pattern

Returns

1 if streamable, 0 if not and -1 in case of error.

xmlStreamPop()

int xmlStreamPop

(

xmlStreamCtxt *

stream

)

push one level from the stream.

Parameters

stream

the stream context

Returns

-1 in case of error, 0 otherwise.

xmlStreamPush()

int xmlStreamPush	(	xmlStreamCtxt *	stream,
		const xmlChar *	name,
		const xmlChar *	ns
	)

Push new data onto the stream.

NOTE: if the call xmlPatterncompile indicated a dictionary, then strings for name and ns will be expected to come from the dictionary. Both name and ns being NULL means the / i.e. the root of the document. This can also act as a reset. Otherwise the function will act as if it has been given an element-node.

Parameters

stream	the stream context
name	the current name
ns	the namespace name

Returns

-1 in case of error, 1 if the current state in the stream is a match and 0 otherwise.

xmlStreamPushAttr()

int xmlStreamPushAttr	(	xmlStreamCtxt *	stream,
		const xmlChar *	name,
		const xmlChar *	ns
	)

Push new attribute data onto the stream.

NOTE: If the call to xmlPatterncompile indicated a dictionary, then strings for name and ns will be expected to come from the dictionary.

Both name and ns being NULL means the root of the document. This can also act as a reset. Otherwise the function will act as if it has been given an attribute-node.

Parameters

stream	the stream context
name	the current name
ns	the namespace name

Returns

-1 in case of error, 1 if the current state in the stream is a match and 0 otherwise.

xmlStreamPushNode()

int xmlStreamPushNode	(	xmlStreamCtxt *	stream,
		const xmlChar *	name,
		const xmlChar *	ns,
		int	nodeType
	)

Push new data onto the stream.

NOTE: if the call xmlPatterncompile indicated a dictionary, then strings for name and ns will be expected to come from the dictionary. Both name and ns being NULL means the / i.e. the root of the document. This can also act as a reset. Different from xmlStreamPush this function can be fed with nodes of type: element-, attribute-, text-, cdata-section-, comment- and processing-instruction-node.

Parameters

stream	the stream context
name	the current name
ns	the namespace name
nodeType	the type of the node being pushed

Returns

-1 in case of error, 1 if the current state in the stream is a match and 0 otherwise.

xmlStreamWantsAnyNode()

int xmlStreamWantsAnyNode

(

xmlStreamCtxt *

streamCtxt

)

Query if the streaming pattern additionally needs to be fed with text-, cdata-section-, comment- and processing-instruction-nodes.

If the result is 0 then only element-nodes and attribute-nodes need to be pushed.

Parameters

streamCtxt

the stream context

Returns

1 in case of need of nodes of the above described types, 0 otherwise. -1 on API errors.