Mini-XML Programmers Manual, Version 2.2.1

Mini-XML Programmers Manual, Version 2.2.1


Michael Sweet
Copyright 2003-2005

Table of Contents



Introduction 1 - Building, Installing, and Packaging Mini-XML 2 - Getting Started with Mini-XML 3 - More Mini-XML Programming Techniques 4 - Using the mxmldoc Utility A - GNU Library General Public License B - Release Notes C - Library Reference

Introduction

This programmers manual describes Mini-XML version 2.2.1, a small XML parsing library that you can use to read and write 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:

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.

Legal Stuff

The Mini-XML library is copyright 2003-2005 by Michael Sweet.

This library is free software; you can redistribute it and/or modify it under the terms of the GNU Library General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public License for more details.

History

Mini-XML was initially developed for the Gimp-Print project to replace the rather large and unwieldy libxml2 library with something substantially smaller and easier-to-use. It all began one morning in June of 2003 when Robert posted the following sentence to the developer's list:

It's bad enough that we require libxml2, but rolling our own XML parser is a bit more than we can handle.

I then replied with:

Given the limited scope of what you use in XML, it should be trivial to code a mini-XML API in a few hundred lines of code.

I took my own challenge and coded furiously for two days to produced the initial public release of Mini-XML, total lines of code: 696. Robert promptly integrated Mini-XML into Gimp-Print and removed libxml2.

Thanks to lots of feedback and support from various developers, Mini-XML has evolved since then to provide a more complete XML implementation and now stands at a whopping 2,974 lines of code, compared to 103,893 lines of code for libxml2 version 2.6.9. Aside from Gimp-Print, Mini-XML is used for the following projects/software applications:

Please email me (mxml @ easysw . com) if you would like your project added or removed from this list, or if you have any comments/quotes you would like me to publish about your experiences with Mini-XML.

Organization of This Document

This manual is organized into the following chapters and appendices:

Notation Conventions

Various font and syntax conventions are used in this guide. Examples and their meanings and uses are explained below:

Example   Description
 
lpstat
lpstat(1)
   The names of commands; the first mention of a command or function in a chapter is followed by a manual page section number.
 
/var
/usr/share/cups/data/testprint.ps
    File and directory names.
 
Request ID is Printer-123    Screen output.
 
lp -d printer filename ENTER    Literal user input; special keys like ENTER are in ALL CAPS.
 
12.3   Numbers in the text are written using the period (.) to indicate the decimal point.

Abbreviations

The following abbreviations are used throughout this manual:

Gb
Gigabytes, or 1073741824 bytes
 
kb
Kilobytes, or 1024 bytes
 
Mb
Megabytes, or 1048576 bytes
 
UTF-8, UTF-16
Unicode Transformation Format, 8-bit or 16-bit
 
W3C
World Wide Web Consortium
 
XML
Extensible Markup Language
 

Other References

The Unicode Standard, Version 4.0, Addison-Wesley, ISBN 0-321-18578-1
The definition of the Unicode character set which is used for XML.
 
Extensible Markup Language (XML) 1.0 (Third Edition)
The XML specification from the World Wide Web Consortium (W3C)
 

1 - Building, Installing, and Packaging Mini-XML

This chapter describes how to build, install, and package Mini-XML on your system.

Compiling Mini-XML

Mini-XML comes with an autoconf-based configure script; just type the following command to get things going:

    ./configure ENTER

The default install prefix is /usr/local, which can be overridden using the --prefix option:

    ./configure --prefix=/foo ENTER

Other configure options can be found using the --help option:

    ./configure --help ENTER

Once you have configured the software, use the make(1) program to do the build and run the test program to verify that things are working, as follows:

    make ENTER

Installing Mini-XML

Use the make command with the install target to install Mini-XML in the configured directories:

    make install ENTER

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.

Creating Mini-XML Packages

Mini-XML includes two files that can be used to create binary packages. The first file is mxml.spec which is used by the rpmbuild(8) software to create Red Hat Package Manager ("RPM") packages which are commonly used on Linux. Since rpmbuild wants to compile the software on its own, you can provide it with the Mini-XML tar file to build the package:

    rpmbuild -ta mxml-version.tar.gz ENTER

The second file is mxml.list which is used by the epm(1) program to create software packages in a variety of formats. The epm program is available from the following URL:

    http://www.easysw.com/epm/

Use the make command with the epm target to create portable and native packages for your system:

    make epm ENTER

The packages are stored in a subdirectory named dist for your convenience. The portable packages utilize scripts and tar files to install the software on the target system; this is especially useful when installing on systems with different Linux distributions. Use the mxml.install script to install the software and mxml.remove script to remove the software.

The native packages will be in the local OS's native format: RPM for Red Hat Linux, DPKG for Debian Linux, PKG for Solaris, and so forth. Use the corresponding commands to install the native packages.


2 - Getting Started with Mini-XML

This chapter describes how to write programs that use Mini-XML to access data in an XML file.

The Basics

Mini-XML provides a single header file which you include:

    #include <mxml.h>

The Mini-XML library is included with your program using the -lmxml option:

    gcc -o myprogram myprogram.c -lmxml ENTER

If you have the pkg-config(1) software installed, you can use it to determine the proper compiler and linker options for your installation:

    pkg-config --cflags mxml ENTER
    pkg-config --libs mxml ENTER

Nodes

Every piece of information in an XML file (elements, text, numbers) is stored in memory in "nodes". 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".

Each node has pointers for the node above (parent), below ( child), to the left (prev), and to the right (next ) of the current node. If you have an XML file like the following:

    <?xml version="1.0"?>
    <data>
        <node>val1</node>
        <node>val2</node>
        <node>val3</node>
        <group>
            <node>val4</node>
            <node>val5</node>
            <node>val6</node>
        </group>
        <node>val7</node>
        <node>val8</node>
        <node>val9</node>
    </data>

the node tree returned by mxmlLoadFile() would look like the following in memory:

    ?xml
      |
    data
      |
    node - node - node - group - node - node - node
      |      |      |      |       |      |      |
    val1   val2   val3     |     val7   val8   val9
                           |
                         node - node - node
                           |      |      |
                         val4   val5   val6

where "-" is a pointer to the next node and "|" is a pointer to the first child node.

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);

Loading 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);

The first argument specifies an existing XML parent node, if any. Normally you will pass NULL for this argument unless you are combining multiple XML sources. The XML file must contain a complete XML document including the ?xml element if the parent node is NULL.

The second argument specifies the stdio file to read from, as opened by fopen() or popen(). You can also use stdin if you are implementing an XML filter program.

The third argument specifies a callback function which returns the value type of the immediate children for a new element node: MXML_INTEGER, MXML_OPAQUE, MXML_REAL, or MXML_TEXT. Load callbacks are described in detail in Chapter 3. The example code uses the MXML_NO_CALLBACK constant which specifies that all data nodes in the document contain whitespace-separated text values.

The mxmlLoadString() function loads XML node trees from a string:

    char buffer[8192];
    mxml_node_t *tree;

    ...
    tree = mxmlLoadString(NULL, buffer, MXML_NO_CALLBACK);

The first and third arguments are the same as used for mxmlLoadFile(). The second argument specifies the string or character buffer to load and must be a complete XML document including the ?xml element if the parent node is NULL.

Saving XML

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 first argument is the XML node tree to save. It should normally be a pointer to the top-level ?xml node in your XML document.

The second argument is the stdio file to write to, as opened by fopen() or popen(). You can also use stdout if you are implementing an XML filter program.

The third argument is the whitespace callback to use when saving the file. Whitespace callbacks are covered in detail in Chapter 3. The example code above uses the MXML_NO_CALLBACK constant to specify that no special whitespace handling is required.

The mxmlSaveAllocString() , and mxmlSaveString() functions save XML node trees to strings:

    char buffer[8192];
    char *ptr;
    mxml_node_t *tree;

    ...
    mxmlSaveString(tree, buffer, sizeof(buffer), MXML_NO_CALLBACK);

    ...
    ptr = mxmlSaveAllocString(tree, MXML_NO_CALLBACK);

The first and last arguments are the same as used for mxmlSaveFile(). The mxmlSaveString() function takes pointer and size arguments for saving the XML document to a fixed-size buffer, while mxmlSaveAllocString() returns a string buffer that was allocated using malloc().

Finding and Iterating Nodes

The mxmlWalkPrev() and mxmlWalkNext()functions can be used to iterate through the XML node tree:

    mxml_node_t *node = mxmlWalkPrev(current, tree, MXML_DESCEND);

    mxml_node_t *node = mxmlWalkNext(current, tree, MXML_DESCEND);

In addition, 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 ...
    }

The MXML_DESCEND argument can actually be one of three constants:


3 - More Mini-XML Programming Techniques

This chapter shows additional ways to use the Mini-XML library in your programs.

Load Callbacks

Chapter 2 introduced the mxmlLoadFile() and mxmlLoadString() functions. The last argument to these functions is a callback function which is used to determine the value type of each data node in an XML document.

Mini-XML defines several standard callbacks for simple XML data files:

You can provide your own callback functions for more complex XML documents. Your callback function will receive a pointer to the current element node and must return the value type of the immediate children for that element node: MXML_INTEGER, MXML_OPAQUE, MXML_REAL, or MXML_TEXT. The function is called after the element and its attributes have been read, so you can look at the element name, attributes, and attribute values to determine the proper value type to return.

The following callback function looks for an attribute named "type" or the element name to determine the value type for its child nodes:

    /*
     * 'type_cb()' - XML data type callback for mxmlLoadFile()...
     */

    mxml_type_t                             /* O - Data type */
    type_cb(mxml_node_t *node)              /* I - Element node */
    {
      const char    *type;                  /* Type string */


     /*
      * You can lookup attributes and/or use the element name, hierarchy, etc...
      */

      if ((type = mxmlElementGetAttr(node, "type")) == NULL)
	type = node->value.element.name;

      if (!strcmp(type, "integer"))
	return (MXML_INTEGER);
      else if (!strcmp(type, "opaque"))
	return (MXML_OPAQUE);
      else if (!strcmp(type, "real"))
	return (MXML_REAL);
      else
	return (MXML_TEXT);
    }

To use this callback function, simply use the name when you call any of the load functions:

    FILE *fp;
    mxml_node_t *tree;

    fp = fopen("filename.xml", "r");
    tree = mxmlLoadFile(NULL, fp, type_cb);
    fclose(fp);

Save Callbacks

Chapter 2 also introduced the mxmlSaveFile(), mxmlSaveString(), and mxmlSaveAllocString() functions. The last argument to these functions is a callback function which is used to automatically insert whitespace in an XML document.

Your callback function will be called up to four times for each element node with a pointer to the node and a "where" value of MXML_WS_BEFORE_OPEN, MXML_WS_AFTER_OPEN, MXML_WS_BEFORE_CLOSE, or MXML_WS_AFTER_CLOSE. The callback function should return NULL if no whitespace should be added and the string to insert (spaces, tabs, carriage returns, and newlines) otherwise. The following whitespace callback can be used to add whitespace to XHTML output to make it more readable in a standard text editor:

    /*
     * 'whitespace_cb()' - Let the mxmlSaveFile() function know when to insert
     *                     newlines and tabs...
     */

    const char *                            /* O - Whitespace string or NULL */
    whitespace_cb(mxml_node_t *node,        /* I - Element node */
        	  int         where)        /* I - Open or close tag? */
    {
      const char *name;                     /* Name of element */

     /*
      * We can conditionally break to a new line before or after any element.
      * These are just common HTML elements...
      */

      name = node->value.element.name;

      if (!strcmp(name, "html") || !strcmp(name, "head") || !strcmp(name, "body") ||
	  !strcmp(name, "pre") || !strcmp(name, "p") ||
	  !strcmp(name, "h1") || !strcmp(name, "h2") || !strcmp(name, "h3") ||
	  !strcmp(name, "h4") || !strcmp(name, "h5") || !strcmp(name, "h6"))
      {
       /*
	* Newlines before open and after close...
	*/

	if (where == MXML_WS_BEFORE_OPEN || where == MXML_WS_AFTER_CLOSE)
	  return ("\n");
      }
      else if (!strcmp(name, "dl") || !strcmp(name, "ol") || !strcmp(name, "ul"))
      {
       /*
	* Put a newline before and after list elements...
	*/

	return ("\n");
      }
      else if (!strcmp(name, "dd") || !strcmp(name, "dt") || !strcmp(name, "li"))
      {
       /*
	* Put a tab before <li>'s, <dd>'s, and <dt>'s, and a newline after them...
	*/

	if (where == MXML_WS_BEFORE_OPEN)
	  return ("\t");
	else if (where == MXML_WS_AFTER_CLOSE)
	  return ("\n");
      }

     /*
      * Return NULL for no added whitespace...
      */

      return (NULL);
    }

To use this callback function, simply use the name when you call any of the save functions:

    FILE *fp;
    mxml_node_t *tree;

    fp = fopen("filename.xml", "w");
    mxmlSaveFile(tree, fp, whitespace_cb);
    fclose(fp);

Custom Data Types

Mini-XML supports custom data types via global load and save callbacks. Only a single set of callbacks can be active at any time, however your callbacks can store additional information in order to support multiple custom data types as needed. The MXML_CUSTOM node type identifies custom data nodes.

The load callback receives a pointer to the current data node and a string of opaque character data from the XML source with character entities converted to the corresponding UTF-8 characters. For example, if we wanted to support a custom date/time type whose value is encoded as "yyyy-mm-ddThh:mm:ssZ" (ISO format), the load callback would look like the following:

    typedef struct
    {
      unsigned      year,                   /* Year */
                    month,                  /* Month */
                    day,                    /* Day */
                    hour,                   /* Hour */
                    minute,                 /* Minute */
                    second;                 /* Second */
      time_t        unix;                   /* UNIX time value */
    } iso_date_time_t;

    int                                     /* I - 0 on success, -1 on error */
    load_custom(mxml_node_t *node,          /* I - Node */
                const char  *data)          /* I - Value */
    {
      iso_date_time_t *dt;                  /* Date/time value */
      struct tm       tmdata;               /* UNIX time data */


     /*
      * Allocate data structure...
      */

      dt = calloc(1, sizeof(iso_date_time_t));

     /*
      * Try reading 6 unsigned integers from the data string...
      */

      if (sscanf(data, "%u-%u-%uT%u:%u:%uZ",
                 &(dt->year), &(dt->month), &(dt->day),
                 &(dt->hour), &(dt->minute), &(dt->second)) != 6)
      {
       /*
        * Unable to read numbers, free the data structure and return an
        * error...
        */

        free(dt);

        return (-1);
      }

     /*
      * Range check values...
      */

      if (dt->month <1 || dt->month > 12 ||
          dt->day  <1 || dt->day > 31 ||
          dt->hour  <0 || dt->hour > 23 ||
          dt->minute  <0 || dt->minute > 59 ||
          dt->second  <0 || dt->second > 59)
      {
       /*
        * Date information is out of range...
        */

        free(dt);

        return (-1);
      }

     /*
      * Convert ISO time to UNIX time in seconds...
      */

      tmdata.tm_year = dt->year - 1900;
      tmdata.tm_mon  = dt->month - 1;
      tmdata.tm_day  = dt->day;
      tmdata.tm_hour = dt->hour;
      tmdata.tm_min  = dt->minute;
      tmdata.tm_sec  = dt->second;

      dt->unix = gmtime(&tmdata);

     /*
      * Assign custom node data and destroy function pointers...
      */

      node->value.custom.data    = dt;
      node->value.custom.destroy = free;

     /*
      * Return with no errors...
      */

      return (0);
    }

The function itself can return 0 on success or -1 if it is unable to decode the custom data or the data contains an error. Custom data nodes contain a void pointer to the allocated custom data for the node and a pointer to a destructor function which will free the custom data when the node is deleted.

The save callback receives the node pointer and returns an allocated string containing the custom data value. The following save callback could be used for our ISO date/time type:

    char *                                  /* I - Allocated string */
    save_custom(mxml_node_t *node)          /* I - Node */
    {
      char            data[255];            /* Data string */
      iso_date_time_t *dt;                  /* ISO date/time pointer */


      dt = (iso_date_time_t *)node->custom.data;

      snprintf(data, sizeof(data), "%04u-%02u-%02uT%02u:%02u:%02uZ",
               dt->year, dt->month, dt->day, dt->hour,
               dt->minute, dt->second);

      return (strdup(data));
    }

You register the callback functions using the mxmlSetCustomHandlers() function:

    mxmlSetCustomHandlers(load_custom, save_custom);

Changing Node Values

All of the examples so far have concentrated on creating and loading new XML data nodes. Many applications, however, need to manipulate or change the nodes during their operation, so Mini-XML provides functions to change node values safely and without leaking memory.

Existing nodes can be changed using the mxmlSetElement(), mxmlSetInteger(), mxmlSetOpaque() , mxmlSetReal(), and mxmlSetText() functions. For example, use the following function call to change a text node to contain the text "new" with leading whitespace:

    mxml_node_t *node;

    mxmlSetText(node, 1, "new");

Formatted Text

The mxmlNewTextf() and mxmlSetTextf() functions create and change text nodes, respectively, using printf-style format strings and arguments. For example, use the following function call to create a new text node:

    mxml_node_t *node;

    node = mxmlNewTextf(node, 1, "%s/%s",
                        path, filename);

Indexing

Mini-XML provides functions for managing indices of nodes. The current implementation provides the same functionality as the mxmlFindElement(). The advantage of using an index is that searching and enumeration of elements is significantly faster. The only disadvantage is that each index is a static snapshot of the XML document, so indices are not well suited to XML data that is updated more often than it is searched. The overhead of creating an index is approximately equal to walking the XML document tree. Nodes in the index are sorted by element name and attribute value.

Indices are stored in mxml_index_t structures. The mxmlIndexNew() function creates a new index:

    mxml_node_t *tree;
    mxml_index_t *ind;

    ind = mxmlIndexNew(tree, "element", "attribute");

The first argument is the XML node tree to index. Normally this will be a pointer to the ?xml element.

The second argument contains the element to index; passing NULL indexes all element nodes alphabetically.

The third argument contains the attribute to index; passing NULL causes only the element name to be indexed.

Once the index is created, the mxmlIndexEnum(), mxmlIndexFind() , and mxmlIndexReset() functions are used to access the nodes in the index. The mxmlIndexReset() function resets the "current" node pointer in the index, allowing you to do new searches and enumerations on the same index. Typically you will call this function prior to your calls to mxmlIndexEnum() and mxmlIndexFind().

The mxmlIndexEnum() function enumerates each of the nodes in the index and can be used in a loop as follows:

    mxml_node_t *node;
    mxml_index_t *ind;

    mxmlIndexReset(ind);

    while ((node = mxmlIndexEnum(ind)) != NULL)
    {
      // do something with node
    }

The mxmlIndexFind() function locates the next occurrence of the named element and attribute value in the index. It can be used to find all matching elements in an index, as follows:

    mxml_node_t *node;
    mxml_index_t *ind;

    mxmlIndexReset(ind);

    while ((node = mxmlIndexFind(ind, "element", "attr-value")) != NULL)
    {
      // do something with node
    }

The second and third arguments represent the element name and attribute value, respectively. A NULL pointer is used to return all elements or attributes in the index. Passing NULL for both the element name and attribute value is equivalent to calling mxmlIndexEnum.

When you are done using the index, delete it using the mxmlIndexDelete() function:

    mxml_index_t *ind;

    mxmlIndexDelete(ind);

4 - Using the mxmldoc Utility

This chapter describes how to use the mxmldoc(1) utility that comes with Mini-XML to automatically generate documentation for your programs.

The Basics

The mxmldoc utility scans C and C++ source and header files and produces an XML file describing the library interface and an XHTML file providing a human-readable reference to the code. Each source and header file must conform to some simple code commenting conventions so that mxmldoc can extract the necessary descriptive text.

The mxmldoc command requires the name of an XML file to store the code information; this file is created and updated as necessary. The XML file is optionally followed by a list of source files to scan. After scanning any source files on the command-line, mxmldoc writes XHTML documentation to the standard output, which can be redirected to the file using the >filename syntax:

    mxmldoc myfile.xml >myfile.html ENTER
    mxmldoc myfile.xml file1.c file2.cxx file3.h >myfile.html ENTER

If no source files are provided on the command-line, the current contents of the XML file are converted to XHTML.

Code Documentation Conventions

As noted previously, source code must be commented properly for mxmldoc to generate correct documentation for the code. Single line comments can use the C++ // comment sequence, however all multi-line comments must use the C /* ... */ comment sequence.

Functions and Methods

All implementations of functions and methods must begin with a comment header describing what the function does, the possible input limits (if any), and the possible output values (if any), and any special information needed, as follows:

    /*
     * 'do_this()' - Compute y = this(x).
     *
     * Notes: none.
     */

    float            /* O - Inverse power value, 0.0 <= y <= 1.1 */
    do_this(float x) /* I - Power value (0.0 <= x <= 1.1) */
    {
      ...
      return (y);
    }

Return/output values are indicated using an "O" prefix, input values are indicated using the "I" prefix, and values that are both input and output use the "IO" prefix for the corresponding in-line comment.

Variables and Class/Structure/Union Members

Each variable or member must be declared on a separate line and must be immediately followed by a comment describing the variable or member, as follows:

    int this_variable;   /* The current state of this */
    int that_variable;   /* The current state of that */

Types

Each type must have a comment block immediately before the typedef, as follows:

    /*
     * This type is for foobar options.
     */
    typedef int this_type_t;

Classes, Structures, and Unions

Each class, structure, and union must have a comment block immediately before the definition, and each member must be documented in accordance with the function and variable documentation requirements, as follows:

    /*
     * This structure is for foobar options.
     */
    struct this_struct_s
    {
      int this_member;   /* Current state for this */
      int that_member;   /* Current state for that */
    };

    /*
     * This class is for barfoo options.
     */
    class this_class_c
    {
      int this_member;   /* Current state for this */
      int that_member;   /* Current state for that */

      /*
       * 'get_this()' - Get the current state for this.
       */
      int                /* O - Current state for this */
      get_this()
      {
        return (this_member);
      }
    };

Enumerations

Each enumeration must have a comment block immediately before the definition describing what the enumeration is for, and each enumeration value must have a comment immediately after the value, as follows:

   /*
    * Enumeration of media trays.
    */
    enum this_enum_e
    {
      THIS_TRAY,   /* This tray */
      THAT_TRAY    /* That tray */
    };

XML Schema

Listing 4-1 shows the XML schema file mxmldoc.xsd which is included with Mini-XML. This schema file can be used to convert the XML files produced by mxmldoc into other formats.

Listing 4-1, XML Schema File "mxmldoc.xsd"
<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema">
  <xsd:annotation>
    <xsd:documentation xml:lang="en">
      Mini-XML 2.2 documentation schema for mxmldoc output.
      Copyright 2003-2005 by Michael Sweet.

      This program is free software; you can redistribute it and/or
      modify it under the terms of the GNU Library General Public
      License as published by the Free Software Foundation; either
      version 2, or (at your option) any later version.

      This program is distributed in the hope that it will be useful,
      but WITHOUT ANY WARRANTY; without even the implied warranty of
      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      GNU General Public License for more details.
    </xsd:documentation>
  </xsd:annotation>

  <!-- basic element definitions -->
  <xsd:element name="argument" type="argumentType"/>
  <xsd:element name="class" type="classType"/>
  <xsd:element name="constant" type="constantType"/>
  <xsd:element name="description" type="xsd:string"/>
  <xsd:element name="enumeration" type="enumerationType"/>
  <xsd:element name="function" type="functionType"/>
  <xsd:element name="mxmldoc" type="mxmldocType"/>
  <xsd:element name="namespace" type="namespaceType"/>
  <xsd:element name="returnvalue" type="returnvalueType"/>
  <xsd:element name="seealso" type="identifierList"/>
  <xsd:element name="struct" type="structType"/>
  <xsd:element name="typedef" type="typedefType"/>
  <xsd:element name="type" type="xsd:string"/>
  <xsd:element name="union" type="unionType"/>
  <xsd:element name="variable" type="variableType"/>

  <!-- descriptions of complex elements -->
  <xsd:complexType name="argumentType">
    <xsd:sequence>
      <xsd:element ref="type" minOccurs="1" maxOccurs="1"/>
      <xsd:element ref="description" minOccurs="0" maxOccurs="1"/>
    </xsd:sequence>
    <xsd:attribute name="default" type="xsd:string" use="optional"/>
    <xsd:attribute name="name" type="identifier" use="required"/>
    <xsd:attribute name="direction" type="direction" use="optional" default="I"/>
  </xsd:complexType>

  <xsd:complexType name="classType">
    <xsd:sequence>
      <xsd:element ref="description" minOccurs="0" maxOccurs="1"/>
      <xsd:choice minOccurs="0" maxOccurs="unbounded">
	<xsd:element ref="class"/>
Listing 4-1, XML Schema File "mxmldoc.xsd" (con't)
	<xsd:element ref="enumeration"/>
	<xsd:element ref="function"/>
	<xsd:element ref="struct"/>
	<xsd:element ref="typedef"/>
	<xsd:element ref="union"/>
	<xsd:element ref="variable"/>
      </xsd:choice>
    </xsd:sequence>
    <xsd:attribute name="name" type="identifier" use="required"/>
    <xsd:attribute name="parent" type="xsd:string" use="optional"/>
  </xsd:complexType>

  <xsd:complexType name="constantType">
    <xsd:sequence>
      <xsd:element ref="description" minOccurs="0" maxOccurs="1"/>
    </xsd:sequence>
    <xsd:attribute name="name" type="identifier" use="required"/>
  </xsd:complexType>

  <xsd:complexType name="enumerationType">
    <xsd:sequence>
      <xsd:element ref="description" minOccurs="0" maxOccurs="1"/>
      <xsd:element ref="constant" minOccurs="1" maxOccurs="unbounded"/>
    </xsd:sequence>
    <xsd:attribute name="name" type="identifier" use="required"/>
  </xsd:complexType>

  <xsd:complexType name="functionType">
    <xsd:sequence>
      <xsd:element ref="returnvalue" minOccurs="0" maxOccurs="1"/>
      <xsd:element ref="description" minOccurs="0" maxOccurs="1"/>
      <xsd:element ref="argument" minOccurs="1" maxOccurs="unbounded"/>
      <xsd:element ref="seealso" minOccurs="0" maxOccurs="1"/>
    </xsd:sequence>
    <xsd:attribute name="name" type="identifier" use="required"/>
    <xsd:attribute name="scope" type="scope" use="optional"/>
  </xsd:complexType>

  <xsd:complexType name="mxmldocType">
    <xsd:choice minOccurs="0" maxOccurs="unbounded">
      <xsd:element ref="class"/>
      <xsd:element ref="enumeration"/>
      <xsd:element ref="function"/>
      <xsd:element ref="namespace"/>
      <xsd:element ref="struct"/>
      <xsd:element ref="typedef"/>
      <xsd:element ref="union"/>
      <xsd:element ref="variable"/>
    </xsd:choice>
  </xsd:complexType>

  <xsd:complexType name="namespaceType">
    <xsd:sequence>
      <xsd:element ref="description" minOccurs="0" maxOccurs="1"/>
      <xsd:choice minOccurs="0" maxOccurs="unbounded">
	<xsd:element ref="class"/>
	<xsd:element ref="enumeration"/>
	<xsd:element ref="function"/>
Listing 4-1, XML Schema File "mxmldoc.xsd" (con't)
	<xsd:element ref="struct"/>
	<xsd:element ref="typedef"/>
	<xsd:element ref="union"/>
	<xsd:element ref="variable"/>
      </xsd:choice>
    </xsd:sequence>
    <xsd:attribute name="name" type="identifier" use="required"/>
  </xsd:complexType>

  <xsd:complexType name="returnvalueType">
    <xsd:sequence>
      <xsd:element ref="type" minOccurs="1" maxOccurs="1"/>
      <xsd:element ref="description" minOccurs="0" maxOccurs="1"/>
    </xsd:sequence>
  </xsd:complexType>

  <xsd:complexType name="structType">
    <xsd:sequence>
      <xsd:element ref="description" minOccurs="0" maxOccurs="1"/>
      <xsd:choice minOccurs="0" maxOccurs="unbounded">
	<xsd:element ref="variable"/>
	<xsd:element ref="function"/>
      </xsd:choice>
    </xsd:sequence>
    <xsd:attribute name="name" type="identifier" use="required"/>
  </xsd:complexType>

  <xsd:complexType name="typedefType">
    <xsd:sequence>
      <xsd:element ref="type" minOccurs="1" maxOccurs="1"/>
      <xsd:element ref="description" minOccurs="0" maxOccurs="1"/>
    </xsd:sequence>
    <xsd:attribute name="name" type="identifier" use="required"/>
  </xsd:complexType>

  <xsd:complexType name="unionType">
    <xsd:sequence>
      <xsd:element ref="description" minOccurs="0" maxOccurs="1"/>
      <xsd:element ref="variable" minOccurs="0" maxOccurs="unbounded"/>
    </xsd:sequence>
    <xsd:attribute name="name" type="identifier" use="required"/>
  </xsd:complexType>

  <xsd:complexType name="variableType">
    <xsd:sequence>
      <xsd:element ref="type" minOccurs="1" maxOccurs="1"/>
      <xsd:element ref="description" minOccurs="0" maxOccurs="1"/>
    </xsd:sequence>
    <xsd:attribute name="name" type="identifier" use="required"/>
  </xsd:complexType>

  <!-- data types -->
  <xsd:simpleType name="direction">
    <xsd:restriction base="xsd:string">
      <xsd:enumeration value="I"/>
      <xsd:enumeration value="O"/>
      <xsd:enumeration value="IO"/>
    </xsd:restriction>
Listing 4-1, XML Schema File "mxmldoc.xsd" (con't)
  </xsd:simpleType>

  <xsd:simpleType name="identifier">
    <xsd:restriction base="xsd:string">
      <xsd:pattern value="[a-zA-Z_(.]([a-zA-Z_(.,)* 0-9])*"/>
    </xsd:restriction>
  </xsd:simpleType>

  <xsd:simpleType name="identifierList">
    <xsd:list itemType="identifier"/>
  </xsd:simpleType>

  <xsd:simpleType name="scope">
    <xsd:restriction base="xsd:string">
      <xsd:enumeration value=""/>
      <xsd:enumeration value="private"/>
      <xsd:enumeration value="protected"/>
      <xsd:enumeration value="public"/>
    </xsd:restriction>
  </xsd:simpleType>
</xsd:schema>

A - GNU Library General Public License

Version 2, June 1991
Copyright (C) 1991 Free Software Foundation, Inc.
59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed.
[This is the first released version of the library GPL. It is numbered 2 because it goes with version 2 of the ordinary GPL.]

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END OF TERMS AND CONDITIONS

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signature of Ty Coon, 1 April 1990
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That's all there is to it!


B - Release Notes

Changes in Mini-XML 2.2.2

Changes in Mini-XML 2.2.1

Changes in Mini-XML 2.2

Changes in Mini-XML 2.1

Changes in Mini-XML 2.0

Changes in Mini-XML 1.3

Changes in Mini-XML 1.2

Changes in Mini-XML 1.1.2

Changes in Mini-XML 1.1.1

Changes in Mini-XML 1.1

Changes in Mini-XML 1.0

Changes in Mini-XML 0.93

Changes in Mini-XML 0.92

Changes in Mini-XML 0.91

Changes in Mini-XML 0.9


C - Library Reference

Contents

Enumerations

mxml_type_e


Description

The XML node type.

Values

NameDescription
MXML_CUSTOMCustom data
MXML_ELEMENTXML element with attributes
MXML_INTEGERInteger value
MXML_OPAQUEOpaque string
MXML_REALReal value
MXML_TEXTText fragment

Functions

mxmlAdd()


Description

Add a node to a tree. Adds the specified node to the parent. If the child argument is not NULL, puts the new node before or after the specified child depending on the value of the where argument. If the child argument is NULL, puts the new node at the beginning of the child list (MXML_ADD_BEFORE) or at the end of the child list (MXML_ADD_AFTER). The constant MXML_ADD_TO_PARENT can be used to specify a NULL child pointer.

Syntax

void
mxmlAdd(
    mxml_node_t * parent,
    int where,
    mxml_node_t * child,
    mxml_node_t * node);

Arguments

NameDescription
parentParent node
whereWhere to add, MXML_ADD_BEFORE or MXML_ADD_AFTER
childChild node for where or MXML_ADD_TO_PARENT
nodeNode to add

Returns

Nothing.

mxmlDelete()


Description

Delete a node and all of its children. If the specified node has a parent, this function first removes the node from its parent using the mxmlRemove() function.

Syntax

void
mxmlDelete(
    mxml_node_t * node);

Arguments

NameDescription
nodeNode to delete

Returns

Nothing.

mxmlElementGetAttr()


Description

Get an attribute. This function returns NULL if the node is not an element or the named attribute does not exist.

Syntax

const char *
mxmlElementGetAttr(
    mxml_node_t * node,
    const char * name);

Arguments

NameDescription
nodeElement node
nameName of attribute

Returns

Attribute value or NULL

mxmlElementSetAttr()


Description

Set an attribute. If the named attribute already exists, the value of the attribute is replaced by the new string value. The string value is copied into the element node. This function does nothing if the node is not an element.

Syntax

void
mxmlElementSetAttr(
    mxml_node_t * node,
    const char * name,
    const char * value);

Arguments

NameDescription
nodeElement node
nameName of attribute
valueAttribute value

Returns

Nothing.

mxmlEntityAddCallback()


Description

Add a callback to convert entities to Unicode.

Syntax

int
mxmlEntityAddCallback(
    int (*cb)(const char *name));

Arguments

NameDescription
(*cb)(const char *name)Callback function to add

Returns

0 on success, -1 on failure

mxmlEntityGetName()


Description

Get the name that corresponds to the character value. If val does not need to be represented by a named entity, NULL is returned.

Syntax

const char *
mxmlEntityGetName(
    int val);

Arguments

NameDescription
valCharacter value

Returns

Entity name or NULL

mxmlEntityGetValue()


Description

Get the character corresponding to a named entity. The entity name can also be a numeric constant. -1 is returned if the name is not known.

Syntax

int
mxmlEntityGetValue(
    const char * name);

Arguments

NameDescription
nameEntity name

Returns

Character value or -1 on error

mxmlEntityRemoveCallback()


Description

Remove a callback.

Syntax

void
mxmlEntityRemoveCallback(
    int (*cb)(const char *name));

Arguments

NameDescription
(*cb)(const char *name)Callback function to remove

Returns

Nothing.

mxmlFindElement()


Description

Find the named element. The search is constrained by the name, attribute name, and value; any NULL names or values are treated as wildcards, so different kinds of searches can be implemented by looking for all elements of a given name or all elements with a specific attribute. The descend argument determines whether the search descends into child nodes; normally you will use MXML_DESCEND_FIRST for the initial search and MXML_NO_DESCEND to find additional direct descendents of the node. The top node argument constrains the search to a particular node's children.

Syntax

mxml_node_t *
mxmlFindElement(
    mxml_node_t * node,
    mxml_node_t * top,
    const char * name,
    const char * attr,
    const char * value,
    int descend);

Arguments

NameDescription
nodeCurrent node
topTop node
nameElement name or NULL for any
attrAttribute name, or NULL for none
valueAttribute value, or NULL for any
descendDescend into tree - MXML_DESCEND, MXML_NO_DESCEND, or MXML_DESCEND_FIRST

Returns

Element node or NULL

mxmlIndexDelete()


Description

Delete an index.

Syntax

void
mxmlIndexDelete(
    mxml_index_t * ind);

Arguments

NameDescription
indIndex to delete

Returns

Nothing.

mxmlIndexEnum()


Description

Return the next node in the index. Nodes are returned in the sorted order of the index.

Syntax

mxml_node_t *
mxmlIndexEnum(
    mxml_index_t * ind);

Arguments

NameDescription
indIndex to enumerate

Returns

Next node or NULL if there is none

mxmlIndexFind()


Description

Find the next matching node. You should call mxmlIndexReset() prior to using this function for the first time with a particular set of "element" and "value" strings. Passing NULL for both "element" and "value" is equivalent to calling mxmlIndexEnum().

Syntax

mxml_node_t *
mxmlIndexFind(
    mxml_index_t * ind,
    const char * element,
    const char * value);

Arguments

NameDescription
indIndex to search
elementElement name to find, if any
valueAttribute value, if any

Returns

Node or NULL if none found

mxmlIndexNew()


Description

Create a new index. The index will contain all nodes that contain the named element and/or attribute. If both "element" and "attr" are NULL, then the index will contain a sorted list of the elements in the node tree. Nodes are sorted by element name and optionally by attribute value if the "attr" argument is not NULL.

Syntax

mxml_index_t *
mxmlIndexNew(
    mxml_node_t * node,
    const char * element,
    const char * attr);

Arguments

NameDescription
nodeXML node tree
elementElement to index or NULL for all
attrAttribute to index or NULL for none

Returns

New index

mxmlIndexReset()


Description

Reset the enumeration/find pointer in the index and return the first node in the index. This function should be called prior to using mxmlIndexEnum() or mxmlIndexFind() for the first time.

Syntax

mxml_node_t *
mxmlIndexReset(
    mxml_index_t * ind);

Arguments

NameDescription
indIndex to reset

Returns

First node or NULL if there is none

mxmlLoadFd()


Description

Load a file descriptor into an XML node tree. The nodes in the specified file are added to the specified top node. If no top node is provided, the XML file MUST be well-formed with a single parent node like <?xml> for the entire file. The callback function returns the value type that should be used for child nodes. If MXML_NO_CALLBACK is specified then all child nodes will be either MXML_ELEMENT or MXML_TEXT nodes. The constants MXML_INTEGER_CALLBACK, MXML_OPAQUE_CALLBACK, MXML_REAL_CALLBACK, and MXML_TEXT_CALLBACK are defined for loading child nodes of the specified type.

Syntax

mxml_node_t *
mxmlLoadFd(
    mxml_node_t * top,
    int fd,
    mxml_type_t (*cb)(mxml_node_t *node));

Arguments

NameDescription
topTop node
fdFile descriptor to read from
(*cb)(mxml_node_t *node)Callback function or MXML_NO_CALLBACK

Returns

First node or NULL if the file could not be read.

mxmlLoadFile()


Description

Load a file into an XML node tree. The nodes in the specified file are added to the specified top node. If no top node is provided, the XML file MUST be well-formed with a single parent node like <?xml> for the entire file. The callback function returns the value type that should be used for child nodes. If MXML_NO_CALLBACK is specified then all child nodes will be either MXML_ELEMENT or MXML_TEXT nodes. The constants MXML_INTEGER_CALLBACK, MXML_OPAQUE_CALLBACK, MXML_REAL_CALLBACK, and MXML_TEXT_CALLBACK are defined for loading child nodes of the specified type.

Syntax

mxml_node_t *
mxmlLoadFile(
    mxml_node_t * top,
    FILE * fp,
    mxml_type_t (*cb)(mxml_node_t *node));

Arguments

NameDescription
topTop node
fpFile to read from
(*cb)(mxml_node_t *node)Callback function or MXML_NO_CALLBACK

Returns

First node or NULL if the file could not be read.

mxmlLoadString()


Description

Load a string into an XML node tree. The nodes in the specified string are added to the specified top node. If no top node is provided, the XML string MUST be well-formed with a single parent node like <?xml> for the entire string. The callback function returns the value type that should be used for child nodes. If MXML_NO_CALLBACK is specified then all child nodes will be either MXML_ELEMENT or MXML_TEXT nodes. The constants MXML_INTEGER_CALLBACK, MXML_OPAQUE_CALLBACK, MXML_REAL_CALLBACK, and MXML_TEXT_CALLBACK are defined for loading child nodes of the specified type.

Syntax

mxml_node_t *
mxmlLoadString(
    mxml_node_t * top,
    const char * s,
    mxml_type_t (*cb)(mxml_node_t *node));

Arguments

NameDescription
topTop node
sString to load
(*cb)(mxml_node_t *node)Callback function or MXML_NO_CALLBACK

Returns

First node or NULL if the string has errors.

mxmlNewCustom()


Description

Create a new custom data node. The new custom node is added to the end of the specified parent's child list. The constant MXML_NO_PARENT can be used to specify that the new element node has no parent. NULL can be passed when the data in the node is not dynamically allocated or is separately managed.

Syntax

mxml_node_t *
mxmlNewCustom(
    mxml_node_t * parent,
    void * data,
    void (*destroy)(void *));

Arguments

NameDescription
parentParent node or MXML_NO_PARENT
dataPointer to data
(*destroy)(void *)Function to destroy data

Returns

New node

mxmlNewElement()


Description

Create a new element node. The new element node is added to the end of the specified parent's child list. The constant MXML_NO_PARENT can be used to specify that the new element node has no parent.

Syntax

mxml_node_t *
mxmlNewElement(
    mxml_node_t * parent,
    const char * name);

Arguments

NameDescription
parentParent node or MXML_NO_PARENT
nameName of element

Returns

New node

mxmlNewInteger()


Description

Create a new integer node. The new integer node is added to the end of the specified parent's child list. The constant MXML_NO_PARENT can be used to specify that the new integer node has no parent.

Syntax

mxml_node_t *
mxmlNewInteger(
    mxml_node_t * parent,
    int integer);

Arguments

NameDescription
parentParent node or MXML_NO_PARENT
integerInteger value

Returns

New node

mxmlNewOpaque()


Description

Create a new opaque string. The new opaque node is added to the end of the specified parent's child list. The constant MXML_NO_PARENT can be used to specify that the new opaque node has no parent. The opaque string must be nul-terminated and is copied into the new node.

Syntax

mxml_node_t *
mxmlNewOpaque(
    mxml_node_t * parent,
    const char * opaque);

Arguments

NameDescription
parentParent node or MXML_NO_PARENT
opaqueOpaque string

Returns

New node

mxmlNewReal()


Description

Create a new real number node. The new real number node is added to the end of the specified parent's child list. The constant MXML_NO_PARENT can be used to specify that the new real number node has no parent.

Syntax

mxml_node_t *
mxmlNewReal(
    mxml_node_t * parent,
    double real);

Arguments

NameDescription
parentParent node or MXML_NO_PARENT
realReal number value

Returns

New node

mxmlNewText()


Description

Create a new text fragment node. The new text node is added to the end of the specified parent's child list. The constant MXML_NO_PARENT can be used to specify that the new text node has no parent. The whitespace parameter is used to specify whether leading whitespace is present before the node. The text string must be nul-terminated and is copied into the new node.

Syntax

mxml_node_t *
mxmlNewText(
    mxml_node_t * parent,
    int whitespace,
    const char * string);

Arguments

NameDescription
parentParent node or MXML_NO_PARENT
whitespace1 = leading whitespace, 0 = no whitespace
stringString

Returns

New node

mxmlNewTextf()


Description

Create a new formatted text fragment node. The new text node is added to the end of the specified parent's child list. The constant MXML_NO_PARENT can be used to specify that the new text node has no parent. The whitespace parameter is used to specify whether leading whitespace is present before the node. The format string must be nul-terminated and is formatted into the new node.

Syntax

mxml_node_t *
mxmlNewTextf(
    mxml_node_t * parent,
    int whitespace,
    const char * format,
    ...);

Arguments

NameDescription
parentParent node or MXML_NO_PARENT
whitespace1 = leading whitespace, 0 = no whitespace
formatPrintf-style frmat string
...Additional args as needed

Returns

New node

mxmlRemove()


Description

Remove a node from its parent. Does not free memory used by the node - use mxmlDelete() for that. This function does nothing if the node has no parent.

Syntax

void
mxmlRemove(
    mxml_node_t * node);

Arguments

NameDescription
nodeNode to remove

Returns

Nothing.

mxmlSaveAllocString()


Description

Save an XML node tree to an allocated string. This function returns a pointer to a string containing the textual representation of the XML node tree. The string should be freed using the free() function when you are done with it. NULL is returned if the node would produce an empty string or if the string cannot be allocated. The callback argument specifies a function that returns a whitespace string or NULL before and after each element. If MXML_NO_CALLBACK is specified, whitespace will only be added before MXML_TEXT nodes with leading whitespace and before attribute names inside opening element tags.

Syntax

char *
mxmlSaveAllocString(
    mxml_node_t * node,
    const char * (*cb)(mxml_node_t *node, int ws));

Arguments

NameDescription
nodeNode to write
(*cb)(mxml_node_t *node, int ws)Whitespace callback or MXML_NO_CALLBACK

Returns

Allocated string or NULL

mxmlSaveFd()


Description

Save an XML tree to a file descriptor. The callback argument specifies a function that returns a whitespace string or NULL before and after each element. If MXML_NO_CALLBACK is specified, whitespace will only be added before MXML_TEXT nodes with leading whitespace and before attribute names inside opening element tags.

Syntax

int
mxmlSaveFd(
    mxml_node_t * node,
    int fd,
    const char * (*cb)(mxml_node_t *node, int ws));

Arguments

NameDescription
nodeNode to write
fdFile descriptor to write to
(*cb)(mxml_node_t *node, int ws)Whitespace callback or MXML_NO_CALLBACK

Returns

0 on success, -1 on error.

mxmlSaveFile()


Description

Save an XML tree to a file. The callback argument specifies a function that returns a whitespace string or NULL before and after each element. If MXML_NO_CALLBACK is specified, whitespace will only be added before MXML_TEXT nodes with leading whitespace and before attribute names inside opening element tags.

Syntax

int
mxmlSaveFile(
    mxml_node_t * node,
    FILE * fp,
    const char * (*cb)(mxml_node_t *node, int ws));

Arguments

NameDescription
nodeNode to write
fpFile to write to
(*cb)(mxml_node_t *node, int ws)Whitespace callback or MXML_NO_CALLBACK

Returns

0 on success, -1 on error.

mxmlSaveString()


Description

Save an XML node tree to a string. This function returns the total number of bytes that would be required for the string but only copies (bufsize - 1) characters into the specified buffer. The callback argument specifies a function that returns a whitespace string or NULL before and after each element. If MXML_NO_CALLBACK is specified, whitespace will only be added before MXML_TEXT nodes with leading whitespace and before attribute names inside opening element tags.

Syntax

int
mxmlSaveString(
    mxml_node_t * node,
    char * buffer,
    int bufsize,
    const char * (*cb)(mxml_node_t *node, int ws));

Arguments

NameDescription
nodeNode to write
bufferString buffer
bufsizeSize of string buffer
(*cb)(mxml_node_t *node, int ws)Whitespace callback or MXML_NO_CALLBACK

Returns

Size of string

mxmlSetCustom()


Description

Set the data and destructor of a custom data node. The node is not changed if it is not a custom node.

Syntax

int
mxmlSetCustom(
    mxml_node_t * node,
    void * data,
    void (*destroy)(void *));

Arguments

NameDescription
nodeNode to set
dataNew data pointer
(*destroy)(void *)New destructor function

Returns

0 on success, -1 on failure

mxmlSetCustomHandlers()


Description

Set the handling functions for custom data. The load function accepts a node pointer and a data string and must return 0 on success and non-zero on error. The save function accepts a node pointer and must return a malloc'd string on success and NULL on error.

Syntax

void
mxmlSetCustomHandlers(
    mxml_custom_load_cb_t load,
    mxml_custom_save_cb_t save);

Arguments

NameDescription
loadLoad function
saveSave function

Returns

Nothing.

mxmlSetElement()


Description

Set the name of an element node. The node is not changed if it is not an element node.

Syntax

int
mxmlSetElement(
    mxml_node_t * node,
    const char * name);

Arguments

NameDescription
nodeNode to set
nameNew name string

Returns

0 on success, -1 on failure

mxmlSetErrorCallback()


Description

Set the error message callback.

Syntax

void
mxmlSetErrorCallback(
    void (*cb)(const char *));

Arguments

NameDescription
(*cb)(const char *)Error callback function

Returns

Nothing.

mxmlSetInteger()


Description

Set the value of an integer node. The node is not changed if it is not an integer node.

Syntax

int
mxmlSetInteger(
    mxml_node_t * node,
    int integer);

Arguments

NameDescription
nodeNode to set
integerInteger value

Returns

0 on success, -1 on failure

mxmlSetOpaque()


Description

Set the value of an opaque node. The node is not changed if it is not an opaque node.

Syntax

int
mxmlSetOpaque(
    mxml_node_t * node,
    const char * opaque);

Arguments

NameDescription
nodeNode to set
opaqueOpaque string

Returns

0 on success, -1 on failure

mxmlSetReal()


Description

Set the value of a real number node. The node is not changed if it is not a real number node.

Syntax

int
mxmlSetReal(
    mxml_node_t * node,
    double real);

Arguments

NameDescription
nodeNode to set
realReal number value

Returns

0 on success, -1 on failure

mxmlSetText()


Description

Set the value of a text node. The node is not changed if it is not a text node.

Syntax

int
mxmlSetText(
    mxml_node_t * node,
    int whitespace,
    const char * string);

Arguments

NameDescription
nodeNode to set
whitespace1 = leading whitespace, 0 = no whitespace
stringString

Returns

0 on success, -1 on failure

mxmlSetTextf()


Description

Set the value of a text node to a formatted string. The node is not changed if it is not a text node.

Syntax

int
mxmlSetTextf(
    mxml_node_t * node,
    int whitespace,
    const char * format,
    ...);

Arguments

NameDescription
nodeNode to set
whitespace1 = leading whitespace, 0 = no whitespace
formatPrintf-style format string
...Additional arguments as needed

Returns

0 on success, -1 on failure

mxmlWalkNext()


Description

Walk to the next logical node in the tree. The descend argument controls whether the first child is considered to be the next node. The top node argument constrains the walk to the node's children.

Syntax

mxml_node_t *
mxmlWalkNext(
    mxml_node_t * node,
    mxml_node_t * top,
    int descend);

Arguments

NameDescription
nodeCurrent node
topTop node
descendDescend into tree - MXML_DESCEND, MXML_NO_DESCEND, or MXML_DESCEND_FIRST

Returns

Next node or NULL

mxmlWalkPrev()


Description

Walk to the previous logical node in the tree. The descend argument controls whether the previous node's last child is considered to be the previous node. The top node argument constrains the walk to the node's children.

Syntax

mxml_node_t *
mxmlWalkPrev(
    mxml_node_t * node,
    mxml_node_t * top,
    int descend);

Arguments

NameDescription
nodeCurrent node
topTop node
descendDescend into tree - MXML_DESCEND, MXML_NO_DESCEND, or MXML_DESCEND_FIRST

Returns

Previous node or NULL

Structures

mxml_attr_s


Description

An XML element attribute value.

Definition

struct mxml_attr_s
{
  char * name;
  char * value;
};

Members

NameDescription
nameAttribute name
valueAttribute value

mxml_custom_s


Description

An XML custom value.

Definition

struct mxml_custom_s
{
  void * data;
};

Members

NameDescription
dataPointer to (allocated) custom data

mxml_index_s


Description

An XML node index.

Definition

struct mxml_index_s
{
  int alloc_nodes;
  char * attr;
  int cur_node;
  mxml_node_t ** nodes;
  int num_nodes;
};

Members

NameDescription
alloc_nodesAllocated nodes in index
attrAttribute used for indexing or NULL
cur_nodeCurrent node
nodesNode array
num_nodesNumber of nodes in index

mxml_node_s


Description

An XML node.

Definition

struct mxml_node_s
{
  struct mxml_node_s * child;
  struct mxml_node_s * last_child;
  struct mxml_node_s * next;
  struct mxml_node_s * parent;
  struct mxml_node_s * prev;
  mxml_type_t type;
  mxml_value_t value;
};

Members

NameDescription
childFirst child node
last_childLast child node
nextNext node under same parent
parentParent node
prevPrevious node under same parent
typeNode type
valueNode value

mxml_text_s


Description

An XML text value.

Definition

struct mxml_text_s
{
  char * string;
  int whitespace;
};

Members

NameDescription
stringFragment string
whitespaceLeading whitespace?

mxml_value_s


Description

An XML element value.

Definition

struct mxml_value_s
{
  mxml_attr_t * attrs;
  char * name;
  int num_attrs;
};

Members

NameDescription
attrsAttributes
nameName of element
num_attrsNumber of attributes

Types

mxml_attr_t


Description

An XML element attribute value.

Definition

typedef struct mxml_attr_s mxml_attr_t;

mxml_custom_t


Description

An XML custom value.

Definition

typedef struct mxml_custom_s mxml_custom_t;

mxml_element_t


Description

An XML element value.

Definition

typedef struct mxml_value_s mxml_element_t;

mxml_index_t


Description

An XML node index.

Definition

typedef struct mxml_index_s mxml_index_t;

mxml_node_t


Description

An XML node.

Definition

typedef struct mxml_node_s mxml_node_t;

mxml_text_t


Description

An XML text value.

Definition

typedef struct mxml_text_s mxml_text_t;

mxml_type_t


Description

The XML node type.

Definition

typedef enum mxml_type_e mxml_type_t;

mxml_value_t


Description

An XML node value.

Definition

typedef union mxml_value_u mxml_value_t;

Unions

mxml_value_u


Description

An XML node value.

Definition

union mxml_value_u
{
  mxml_custom_t custom;
  mxml_element_t element;
  int integer;
  char * opaque;
  double real;
  mxml_text_t text;
};

Members

NameDescription
customCustom data
elementElement
integerInteger number
opaqueOpaque string
realReal number
textText fragment