mxml - mini-xml library

#include <mxml.h>

-lmxml

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:

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Reading and writing of UTF-8 encoded XML files.

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Reading and writing of UTF-8 encoded XML strings.

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Data is stored in a linked-list tree structure, preserving the XML data hierarchy.

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Supports arbitrary element names, attributes, and attribute values with no preset limits, just available memory.

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Supports integer, real, opaque ("cdata"), and text data types in "leaf" nodes.

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Functions for creating and managing trees of data.

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"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, nor does it support character entities other than those required by the XML specification. Also, since Mini-XML does not support the UTF-16 encoding, it is technically not a conforming XML consumer/client.

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.easysw.com/~mike/mxml/", 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 ... }

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);

mxmldoc(1), Mini-XML Programmers Manual, http://www.easysw.com/~mike/mxml/

Copyright 2003-2005 by Michael Sweet.