fasterxml - the faster xml parser

1.Overview
2.Compiling and installation
3.Basic Use
4.Performance
5.Finally

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1.Overview

Fasterxml is a fast XML(SAX) parser. It directly parse XML text, call registered event functions, fast access XML content of your interest.
Fasterxml is used in access XML data read-only, such as parsing XML configuration file, or unpacking large XML. Because it is not like the DOM model need to construct a complete document tree, so the speed is very fast, almost close to the performance of strlen(). 
Fasterxml is very small, the entire source code consists of a pair fasterxml.h and fasterxml.c,500 lines,13KB,not depend on any other libraries, easily embedded in your project.

2.Compiling and installation

for example, Linux
[code]
$ cd src
$ make -f makefile.Linux install
gcc -g -fPIC -O2 -Wall -Werror -fno-strict-aliasing -I.  -c fasterxml.c
gcc -g -fPIC -O2 -Wall -Werror -fno-strict-aliasing -o libfasterxml.so fasterxml.o -shared -L.
cp -f libfasterxml.so /usr/lib/exlib/
cp -f fasterxml.h /usr/include/fasterxml/
[/code]

3.Basic Use

Only three interface functions in fasterxml

[code]
typedef int funcCallbackOnXmlNode( int type , char *xpath , int xpath_len , int xpath_size , char *node , int node_len , char *properties , int properties_len , char *content , int content_len , void *p );
int TravelXmlBuffer( char *xml_buffer , char *xpath , int xpath_size
		 , funcCallbackOnXmlNode *pfuncCallbackOnXmlNode
		 , void *p );
int TravelXmlBuffer4( char *xml_buffer , char *xpath , int xpath_size
		 , funcCallbackOnXmlNode *pfuncCallbackOnXmlNode
		 , funcCallbackOnXmlNode *pfuncCallbackOnEnterXmlNode
		 , funcCallbackOnXmlNode *pfuncCallbackOnLeaveXmlNode
		 , funcCallbackOnXmlNode *pfuncCallbackOnXmlLeaf
		 , void *p );
[/code]
Function TravelXmlBuffer() read XML text and fast parsing, call pfuncCallbackOnXmlNode() when accessing XML branches or leaves , application can be determined branches or leaves events by type and xpath, visit data interested.
Function TravelXmlBuffer4 is event subdivided version.
access attributes of the current node collection
[code]
typedef int funcCallbackOnXmlProperty( char *xpath , int xpath_len , int xpath_size , char *propname , int propname_len , char *propvalue , int propvalue_len , void *p );
_WINDLL_FUNC int TravelXmlPropertiesBuffer( char *properties , int properties_len , char *xpath , int xpath_len , int xpath_size
					   , funcCallbackOnXmlProperty *pfuncCallbackOnXmlProperty
					   , void *p );
[/code]

The following is a simple example
[code]
funcCallbackOnXmlProperty CallbackOnXmlProperty ;
int CallbackOnXmlProperty( char *xpath , int xpath_len , int xpath_size , char *propname , int propname_len , char *propvalue , int propvalue_len , void *p )
{
	printf( "    PROPERTY p[%s] xpath[%s] propname[%.*s] propvalue[%.*s]\n" , (char*)p , xpath , propname_len , propname , propvalue_len , propvalue );
	
	return 0;
}

funcCallbackOnXmlNode CallbackOnXmlNode ;
int CallbackOnXmlNode( int type , char *xpath , int xpath_len , int xpath_size , char *nodename , int nodename_len , char *properties , int properties_len , char *content , int content_len , void *p )
{
	int		nret = 0 ;
	
	if( type & FASTXML_NODE_BRANCH )
	{
		if( type & FASTXML_NODE_ENTER )
		{
			printf( "ENTER-BRANCH p[%s] xpath[%s] nodename[%.*s] properties[%.*s]\n" , (char*)p , xpath , nodename_len , nodename , properties_len , properties );
		}
		else if( type & FASTXML_NODE_LEAVE )
		{
			printf( "LEAVE-BRANCH p[%s] xpath[%s] nodename[%.*s] properties[%.*s]\n" , (char*)p , xpath , nodename_len , nodename , properties_len , properties );
		}
		else
		{
			printf( "BRANCH       p[%s] xpath[%s] nodename[%.*s] properties[%.*s]\n" , (char*)p , xpath , nodename_len , nodename , properties_len , properties );
		}
	}
	else if( type & FASTXML_NODE_LEAF )
	{
		printf( "LEAF         p[%s] xpath[%s] nodename[%.*s] properties[%.*s] content[%.*s]\n" , (char*)p , xpath , nodename_len , nodename , properties_len , properties , content_len , content );
	}

	if( properties && properties[0] )
	{
		nret = TravelXmlPropertiesBuffer( properties , properties_len , xpath , xpath_len , xpath_size , & CallbackOnXmlProperty , p ) ;
		if ( nret )
			return nret;
	}
	
	return 0;
}

...
char	xpath[ 1024 + 1 ] ;
char	*xml_buffer = NULL ;
char	*p = "hello world" ;

memset( xpath , 0x00 , sizeof(xpath) );
nret = TravelXmlBuffer( xml_buffer , xpath , sizeof(xpath) , & CallbackOnXmlNode , p ) ;
free( xml_buffer );
if( nret && nret != FASTXML_INFO_END_OF_BUFFER )
{
	printf( "TravelXmlTree failed[%d]\n" , nret );
	return nret;
}
...
[/code]

For output
[code]
$ cat test_basic.xml
<?xml version="1.0" encoding="UTF-8"?>
<root>
	<leaf>content</leaf>
	<sub_branch>
		<sub_leaf>sub_content</sub_leaf>
	</sub_branch>
	<self_branch />
	<self_branch2/>
	<branch_has_property propname1=propvalue1>
		<leaf_has_property propname1="prop value1" propname2="prop value2" >content</leaf_has_property>
	</branch_has_property>
</root>
$ test_fasterxml test_basic.xml
BRANCH       p[hello world] xpath[/xml] nodename[xml] properties[ version="1.0" encoding="UTF-8"?]
    PROPERTY p[hello world] xpath[/xml.version] propname[version] propvalue[1.0]
    PROPERTY p[hello world] xpath[/xml.encoding] propname[encoding] propvalue[UTF-8]
ENTER-BRANCH p[hello world] xpath[/root] nodename[root] properties[]
LEAF         p[hello world] xpath[/root/leaf] nodename[leaf] properties[] content[content]
ENTER-BRANCH p[hello world] xpath[/root/sub_branch] nodename[sub_branch] properties[]
LEAF         p[hello world] xpath[/root/sub_branch/sub_leaf] nodename[sub_leaf] properties[] content[sub_content]
LEAVE-BRANCH p[hello world] xpath[/root/sub_branch] nodename[sub_branch] properties[]
BRANCH       p[hello world] xpath[/root/self_branch] nodename[self_branch] properties[ /]
BRANCH       p[hello world] xpath[/root/self_branch2] nodename[self_branch2] properties[/]
ENTER-BRANCH p[hello world] xpath[/root/branch_has_property] nodename[branch_has_property] properties[ propname1=propvalue1]
    PROPERTY p[hello world] xpath[/root/branch_has_property.propname1] propname[propname1] propvalue[propvalue1]
LEAF         p[hello world] xpath[/root/branch_has_property/leaf_has_property] nodename[leaf_has_property] properties[ propname1="prop value1" propname2="prop value2" ] content[content]
    PROPERTY p[hello world] xpath[/root/branch_has_property/leaf_has_property.propname1] propname[propname1] propvalue[prop value1]
    PROPERTY p[hello world] xpath[/root/branch_has_property/leaf_has_property.propname2] propname[propname2] propvalue[prop value2]
LEAVE-BRANCH p[hello world] xpath[/root/branch_has_property] nodename[branch_has_property] properties[]
LEAVE-BRANCH p[hello world] xpath[/root] nodename[root] properties[]
[/code]

You can transform event callback function, rapid access XML nodes, for example, according to certain XPATH then fill c struct members.

4.Performance

Fastxml's performance is very high, below is fasterxml and rapidxml pressure measurement
[code]
~/exsrc/fasterxml-1.0.0/test $ ls -l test_big_and_lang.xml
-rw-r--r-- 1 calvin calvin 622511 Sep 21 10:51 test_big_and_lang.xml
~/exsrc/fasterxml-1.0.0/test $ wc test_big_and_lang.xml
17870  26332 622511 test_big_and_lang.xml
[/code]

fasterxml runs 10 times, get the best results
[code]
~/exsrc/fasterxml-1.0.0/test $ time ./press_fastxml test_big_and_lang.xml 1000
Elapse 5 seconds
real    0m5.130s
user    0m3.402s
sys     0m0.007s
[/code]
Iterates through all leaves and branches on 1000 times, it took about 5 seconds.

rapidxml runs 10 times, get the best results
[code]
~/exsrc/fasterxml-1.0.0/test_rapidxml $ time ./press_rapidxml ../test/test_big_and_lang.xml 1000
Elapse 19 seconds

real    0m19.169s
user    0m0.923s
sys     0m18.265s
[/code]
Iterates through all leaves and branches on 1000 times, it took about 19 seconds.

fasterxml is faster than rapidxml about 3 times.

5.Finally

Welcome to use fasterxml, if you have any problems, please tell me, thank you ^_^
Project home page : [url]https://github.com/calvinwilliams/fasterxml[/url]
Author email      : calvinwilliams.c@gmail.com