README - 2014-10-19
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INTRODUCTION
This README file describes the Mini-XML library version 2.9.
Mini-XML is a small XML parsing library that you can use to read XML and
XML-like data files in your application without requiring large non-standard
libraries. Mini-XML only requires an ANSI C compatible compiler (GCC works,
as do most vendors' ANSI C compilers) and a "make" program.
Mini-XML provides the following functionality:
- Reading of UTF-8 and UTF-16 and writing of UTF-8 encoded XML files and
strings.
- Data is stored in a linked-list tree structure, preserving the XML
data hierarchy.
- Supports arbitrary element names, attributes, and attribute values
with no preset limits, just available memory.
- Supports integer, real, opaque ("cdata"), and text data types in
"leaf" nodes.
- Functions for creating and managing trees of data.
- "Find" and "walk" functions for easily locating and navigating trees
of data.
Mini-XML doesn't do validation or other types of processing on the data
based upon schema files or other sources of definition information.
BUILDING Mini-XML
Mini-XML comes with an autoconf-based configure script; just type the
following command to get things going:
./configure
The default install prefix is /usr/local, which can be overridden using the
--prefix option:
./configure --prefix=/foo
Other configure options can be found using the --help option:
./configure --help
Once you have configured the software, type "make" to do the build and run
the test program to verify that things are working, as follows:
make
If you are using Mini-XML under Microsoft Windows with Visual C++, use the
included project files in the "vcnet" subdirectory to build the library
instead.
INSTALLING Mini-XML
The "install" target will install Mini-XML in the lib and include
directories:
make install
Once you have installed it, use the "-lmxml" option to link your application
against it.
DOCUMENTATION
The documentation is available in the "doc" subdirectory in the files
"mxml.html" (HTML) and "mxml.pdf" (PDF). You can also look at the
"testmxml.c" and "mxmldoc.c" source files for examples of using Mini-XML.
Mini-XML provides a single header file which you include:
#include <mxml.h>
Nodes are defined by the "mxml_node_t" structure; the "type" member defines
the node type (element, integer, opaque, real, or text) which determines
which value you want to look at in the "value" union. New nodes can be
created using the "mxmlNewElement()", "mxmlNewInteger()", "mxmlNewOpaque()",
"mxmlNewReal()", and "mxmlNewText()" functions. Only elements can have
child nodes, and the top node must be an element, usually "?xml".
You load an XML file using the "mxmlLoadFile()" function:
FILE *fp;
mxml_node_t *tree;
fp = fopen("filename.xml", "r");
tree = mxmlLoadFile(NULL, fp, MXML_NO_CALLBACK);
fclose(fp);
Similarly, you save an XML file using the "mxmlSaveFile()" function:
FILE *fp;
mxml_node_t *tree;
fp = fopen("filename.xml", "w");
mxmlSaveFile(tree, fp, MXML_NO_CALLBACK);
fclose(fp);
The "mxmlLoadString()", "mxmlSaveAllocString()", and "mxmlSaveString()"
functions load XML node trees from and save XML node trees to strings:
char buffer[8192];
char *ptr;
mxml_node_t *tree;
...
tree = mxmlLoadString(NULL, buffer, MXML_NO_CALLBACK);
...
mxmlSaveString(tree, buffer, sizeof(buffer), MXML_NO_CALLBACK);
...
ptr = mxmlSaveAllocString(tree, MXML_NO_CALLBACK);
You can find a named element/node using the "mxmlFindElement()" function:
mxml_node_t *node = mxmlFindElement(tree, tree, "name", "attr",
"value", MXML_DESCEND);
The "name", "attr", and "value" arguments can be passed as NULL to act as
wildcards, e.g.:
/* Find the first "a" element */
node = mxmlFindElement(tree, tree, "a", NULL, NULL, MXML_DESCEND);
/* Find the first "a" element with "href" attribute */
node = mxmlFindElement(tree, tree, "a", "href", NULL, MXML_DESCEND);
/* Find the first "a" element with "href" to a URL */
node = mxmlFindElement(tree, tree, "a", "href",
"http://www.minixml.org/",
MXML_DESCEND);
/* Find the first element with a "src" attribute*/
node = mxmlFindElement(tree, tree, NULL, "src", NULL, MXML_DESCEND);
/* Find the first element with a "src" = "foo.jpg" */
node = mxmlFindElement(tree, tree, NULL, "src", "foo.jpg",
MXML_DESCEND);
You can also iterate with the same function:
mxml_node_t *node;
for (node = mxmlFindElement(tree, tree, "name", NULL, NULL,
MXML_DESCEND);
node != NULL;
node = mxmlFindElement(node, tree, "name", NULL, NULL,
MXML_DESCEND))
{
... do something ...
}
The "mxmlFindPath()" function finds the (first) value node under a specific
element using a "path":
mxml_node_t *value = mxmlFindPath(tree, "path/to/*/foo/bar");
The "mxmlGetInteger()", "mxmlGetOpaque()", "mxmlGetReal()", and
"mxmlGetText()" functions retrieve the value from a node:
mxml_node_t *node;
int intvalue = mxmlGetInteger(node);
const char *opaquevalue = mxmlGetOpaque(node);
double realvalue = mxmlGetReal(node);
int whitespacevalue;
const char *textvalue = mxmlGetText(node, &whitespacevalue);
Finally, once you are done with the XML data, use the "mxmlDelete()"
function to recursively free the memory that is used for a particular node
or the entire tree:
mxmlDelete(tree);
GETTING HELP AND REPORTING PROBLEMS
The Mini-XML project page provides access to a discussion forum and bug
reporting page:
http://www.msweet.org/projects.php/Mini-XML
LEGAL STUFF
The Mini-XML library is Copyright 2003-2014 by Michael Sweet. License terms
are described in the file "COPYING".