Added a custom tag (void*) to the Node object and a callback before freeing a Node. This to aid in resource management for a scripting language with auto-garbage collection.

build/vc10/ixml.vcxproj

@@ -1,4 +1,4 @@
-<?xml version="1.0" encoding="utf-8"?>
+<?xml version="1.0" encoding="utf-8"?>
 <Project DefaultTargets="Build" ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <ItemGroup Label="ProjectConfigurations">
     <ProjectConfiguration Include="Debug Lib|Win32">
@@ -158,7 +158,7 @@
     <ClCompile>
       <Optimization>Disabled</Optimization>
       <AdditionalIncludeDirectories>..\..\ixml\inc;..\..\ixml\src\inc;..\inc;..\..\upnp\inc;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <PreprocessorDefinitions>DEBUG;WIN32;_USRDLL;LIBUPNP_EXPORTS;UPNP_USE_MSVCPP;_CRT_NONSTDC_NO_WARNINGS;_CRT_NONSTDC_NO_DEPRECATE;_CRT_SECURE_NO_WARNINGS;_CRT_SECURE_NO_DEPRECATE;_SECURE_SCL;_SCL_SECURE_NO_WARNINGS;_SCL_SECURE_NO_DEPRECATE;_AFX_SECURE_NO_WARNINGS;_AFX_SECURE_NO_DEPRECATE;_SECURE_ATL;_ATL_NO_COM_SUPPORT;_ATL_SECURE_NO_WARNINGS;_ATL_SECURE_NO_DEPRECATE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>DEBUG;WIN32;_USRDLL;LIBUPNP_EXPORTS;UPNP_USE_MSVCPP;SCRIPTSUPPORT;_CRT_NONSTDC_NO_WARNINGS;_CRT_NONSTDC_NO_DEPRECATE;_CRT_SECURE_NO_WARNINGS;_CRT_SECURE_NO_DEPRECATE;_SECURE_SCL;_SCL_SECURE_NO_WARNINGS;_SCL_SECURE_NO_DEPRECATE;_AFX_SECURE_NO_WARNINGS;_AFX_SECURE_NO_DEPRECATE;_SECURE_ATL;_ATL_NO_COM_SUPPORT;_ATL_SECURE_NO_WARNINGS;_ATL_SECURE_NO_DEPRECATE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <MinimalRebuild>true</MinimalRebuild>
       <BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
       <RuntimeLibrary>MultiThreadedDebugDLL</RuntimeLibrary>

ixml/inc/ixml.h

@@ -158,6 +158,13 @@ typedef struct _IXML_Document *Docptr;
 
 typedef struct _IXML_Node     *Nodeptr;
 
+#ifdef SCRIPTSUPPORT
+/*!
+ * \brief Signature for GC support method, called before a node is freed.
+ */
+typedef void (*IXML_BeforeFreeNode_t) (Nodeptr obj);
+#endif
+
 
 /*!
  * \brief Data structure common to all types of nodes.
@@ -178,6 +185,9 @@ typedef struct _IXML_Node
 	Nodeptr           nextSibling;
 	Nodeptr           firstAttr;
 	Docptr            ownerDocument;
+#ifdef SCRIPTSUPPORT
+	void*             ctag;			// custom tag
+#endif
 } IXML_Node;
 
 
@@ -625,9 +635,29 @@ EXPORT_SPEC BOOL ixmlNode_hasAttributes(
  * \brief Frees a \b Node and all \b Nodes in its subtree.
  */
 EXPORT_SPEC void ixmlNode_free(
-	/*! [in] The \b Node tree to free. */
+	/*! [in] The \b Node tree to free. Before it is freed, the handler
+	 * set by \b ixmlSetBeforeFree will be called, the order will be
+	 * top-down.
+	 */
 	IXML_Node *nodeptr);
 
+#ifdef SCRIPTSUPPORT
+/*!
+ * \brief Sets the custom tag for the node.
+ */
+EXPORT_SPEC void ixmlNode_setCTag(
+	/*! [in] The \b Node to which to attach the tag. */
+	IXML_Node *nodeptr,
+	/*! [in] The \b tag to attach. */
+	void *ctag);
+
+/*!
+ * \brief Gets the custom tag for the node.
+ */
+EXPORT_SPEC void* ixmlNode_getCTag(
+	/*! [in] The \b Node from which to get the tag. */
+	IXML_Node *nodeptr);
+#endif
 /* @} Interface Node */
 
 
@@ -1737,6 +1767,18 @@ EXPORT_SPEC void ixmlRelaxParser(
 	 */
 	char errorChar);
 
+#ifdef SCRIPTSUPPORT
+/*!
+ * \brief Sets the handler to call before a node is freed.
+ */
+EXPORT_SPEC void ixmlSetBeforeFree(
+	/*! [in] If \b hndlr is set to a function, it will be called before any
+	 * node is freed, with the node as its parameter. This allows scripting
+	 * languages to do their garbage collection, without maintaining their
+	 * own tree structure.
+	 */
+	IXML_BeforeFreeNode_t hndlr);
+#endif
 
 /*!
  * \brief Parses an XML text buffer converting it into an IXML DOM representation.

ixml/src/inc/ixmlparser.h

@@ -120,6 +120,25 @@ void Parser_setErrorChar(
 	/*! [in] The character to become the error character. */
 	char c);
 
+#ifdef SCRIPTSUPPORT
+/*!
+ * \brief Sets the handler to call before a node is freed.
+ *
+ * If \b hndlr is set to a function, it will be called before any
+ * node is freed, with the node as its parameter. This allows scripting
+ * languages to do their garbage collection, without maintaining their
+ * own tree structure.
+ */
+void Parser_setBeforeFree(
+	/*! [in] The handler callback to call before each node to be freed. */
+	IXML_BeforeFreeNode_t hndlr);
+
+/*!
+ * \brief Gets the handler to call before a node is freed.
+ */
+IXML_BeforeFreeNode_t Parser_getBeforeFree();
+#endif
+
 
 /*!
  * \brief Fees a node contents.

ixml/src/ixml.c

@@ -417,6 +417,13 @@ void ixmlRelaxParser(char errorChar)
 	Parser_setErrorChar(errorChar);
 }
 
+#ifdef SCRIPTSUPPORT
+void ixmlSetBeforeFree(IXML_BeforeFreeNode_t hndlr)
+{
+	Parser_setBeforeFree(hndlr);
+}
+#endif
+
 
 int ixmlParseBufferEx(const char *buffer, IXML_Document **retDoc)
 {

ixml/src/ixmlparser.c

@@ -55,6 +55,9 @@
 
 
 static char g_error_char = '\0';
+#ifdef SCRIPTSUPPORT
+static IXML_BeforeFreeNode_t Before_Free_callback;
+#endif
 
 
 static const char LESSTHAN = '<';
@@ -2498,6 +2501,17 @@ void Parser_setErrorChar(char c)
 	g_error_char = c;
 }
 
+#ifdef SCRIPTSUPPORT
+void Parser_setBeforeFree(IXML_BeforeFreeNode_t hndlr)
+{
+	Before_Free_callback = hndlr;
+}
+
+IXML_BeforeFreeNode_t Parser_getBeforeFree()
+{
+	return Before_Free_callback;
+}
+#endif
 
 /*!
  * \brief Initializes a xml parser.

ixml/src/node.c

@@ -107,6 +107,10 @@ static void ixmlNode_freeSingleNode(
 void ixmlNode_free(IXML_Node *nodeptr)
 {
 	if (nodeptr != NULL) {
+#ifdef SCRIPTSUPPORT
+		IXML_BeforeFreeNode_t hndlr = Parser_getBeforeFree();
+		if (hndlr != NULL) hndlr(nodeptr);
+#endif
 		ixmlNode_free(nodeptr->firstChild);
 		ixmlNode_free(nodeptr->nextSibling);
 		ixmlNode_free(nodeptr->firstAttr);
@@ -1377,3 +1381,17 @@ ErrorHandler:
 	return IXML_INSUFFICIENT_MEMORY;
 }
 
+#ifdef SCRIPTSUPPORT
+void ixmlNode_setCTag(IXML_Node *nodeptr, void *ctag)
+{
+	if (nodeptr != NULL) nodeptr->ctag = ctag;
+}
+
+void* ixmlNode_getCTag(IXML_Node *nodeptr)
+{
+	if (nodeptr != NULL)
+		return nodeptr->ctag;
+	else
+		return NULL;
+}
+#endif