added a new routine xmlBuildRelativeURI needed for enhancement of

* uri.c, include/libxml/uri.h: added a new routine
  xmlBuildRelativeURI needed for enhancement of xinclude.c
* xinclude.c: changed handling of xml:base (bug 135864)
* result/XInclude/*: results of 5 tests changed as a result
  of the above change

ChangeLog

@@ -1,3 +1,11 @@
+Mon Jun  7 16:57:43 HKT 2004 William Brack <wbrack@mmm.com.hk>
+
+	* uri.c, include/libxml/uri.h: added a new routine
+	  xmlBuildRelativeURI needed for enhancement of xinclude.c
+	* xinclude.c: changed handling of xml:base (bug 135864)
+	* result/XInclude/*: results of 5 tests changed as a result
+	  of the above change
+
 Fri Jun  4 11:27:37 CEST 2004 Daniel Veillard <daniel@veillard.com>
 
 	* test/schemas/* result/schemas/*: added a bunch of tests from

include/libxml/uri.h

@@ -47,8 +47,11 @@ struct _xmlURI {
 XMLPUBFUN xmlURIPtr XMLCALL	
 		xmlCreateURI		(void);
 XMLPUBFUN xmlChar * XMLCALL	
-		xmlBuildURI		(const xmlChar *URI,
-	                        	 const xmlChar *base);
+		xmlBuildURI			(const xmlChar *URI,
+	                         const xmlChar *base);
+XMLPUBFUN xmlChar * XMLCALL	
+		xmlBuildRelativeURI	(const xmlChar *URI,
+	                         const xmlChar *base);
 XMLPUBFUN xmlURIPtr XMLCALL	
 		xmlParseURI		(const char *str);
 XMLPUBFUN int XMLCALL		

result/XInclude/docids.xml

@@ -11,7 +11,7 @@
 <isid myid="dup"/>
 </doc>
 <!-- including another XML document with IDs -->
-<doc xml:base="test/XInclude/ents/ids.xml">
+<doc xml:base="../../../test/XInclude/ents/ids.xml">
 <isid myid="dup"/>
 <isid myid="foo"/>
 <isid myid="bar"/>

result/XInclude/include.xml

@@ -1,7 +1,7 @@
 <?xml version="1.0"?>
 <x xmlns:xinclude="http://www.w3.org/2001/XInclude">
    <!-- Simple test of including another XML document -->
-   <doc xml:base="test/XInclude/ents/something.xml">
+   <doc xml:base="../../../test/XInclude/ents/something.xml">
 <p>something</p>
 <p>really</p>
 <p>simple</p>

result/XInclude/nodes.xml

@@ -1,5 +1,5 @@
 <?xml version="1.0"?>
 <x xmlns:xinclude="http://www.w3.org/2001/XInclude">
    <!-- Simple test of including a set of nodes from an XML document -->
-   <p xml:base="test/XInclude/ents/something.xml">something</p><p xml:base="test/XInclude/ents/something.xml">really</p><p xml:base="test/XInclude/ents/something.xml">simple</p>
+   <p xml:base="../../../test/XInclude/ents/something.xml">something</p><p xml:base="../../../test/XInclude/ents/something.xml">really</p><p xml:base="../../../test/XInclude/ents/something.xml">simple</p>
 </x>

result/XInclude/nodes2.xml

@@ -1,5 +1,5 @@
 <?xml version="1.0"?>
 <x xmlns:xinclude="http://www.w3.org/2003/XInclude">
    <!-- Simple test of including a set of nodes from an XML document -->
-   <p xml:base="test/XInclude/ents/something.xml">something</p><p xml:base="test/XInclude/ents/something.xml">really</p><p xml:base="test/XInclude/ents/something.xml">simple</p>
+   <p xml:base="../../../test/XInclude/ents/something.xml">something</p><p xml:base="../../../test/XInclude/ents/something.xml">really</p><p xml:base="../../../test/XInclude/ents/something.xml">simple</p>
 </x>

result/XInclude/recursive.xml

@@ -1,3 +1,3 @@
 <?xml version="1.0"?>
-<this><sub-inc xml:base="test/XInclude/ents/sub-inc.ent">is a test
+<this><sub-inc xml:base="../../../test/XInclude/ents/sub-inc.ent">is a test
 </sub-inc></this>

uri.c

@@ -1971,6 +1971,181 @@ done:
     return(val);
 }
 
+/**
+ * xmlBuildRelativeURI:
+ * @URI:  the URI reference under consideration
+ * @base:  the base value
+ *
+ * Expresses the URI of the reference in terms relative to the
+ * base.  Some examples of this operation include:
+ *     base = "http://site1.com/docs/book1.html"
+ *        URI input                        URI returned
+ *     docs/pic1.gif                    pic1.gif
+ *     docs/img/pic1.gif                img/pic1.gif
+ *     img/pic1.gif                     ../img/pic1.gif
+ *     http://site1.com/docs/pic1.gif   pic1.gif
+ *     http://site2.com/docs/pic1.gif   http://site2.com/docs/pic1.gif
+ *
+ *     base = "docs/book1.html"
+ *        URI input                        URI returned
+ *     docs/pic1.gif                    pic1.gif
+ *     docs/img/pic1.gif                img/pic1.gif
+ *     img/pic1.gif                     ../img/pic1.gif
+ *     http://site1.com/docs/pic1.gif   http://site1.com/docs/pic1.gif
+ *
+ *
+ * Note: if the URI reference is really wierd or complicated, it may be
+ *       worthwhile to first convert it into a "nice" one by calling
+ *       xmlBuildURI (using 'base') before calling this routine,
+ *       since this routine (for reasonable efficiency) assumes URI has
+ *       already been through some validation.
+ *
+ * Returns a new URI string (to be freed by the caller) or NULL in case
+ * error.
+ */
+xmlChar *
+xmlBuildRelativeURI (const xmlChar * URI, const xmlChar * base)
+{
+    xmlChar *val = NULL;
+    int ret;
+    int ix;
+    int pos = 0;
+    int nbslash = 0;
+    xmlURIPtr ref = NULL;
+    xmlURIPtr bas = NULL;
+    xmlChar *bptr, *uptr, *vptr;
+
+    if ((URI == NULL) || (*URI == 0))
+	return NULL;
+    /*
+     * Special case - if URI starts with '.', we assume it's already
+     * in relative form, so nothing to do.
+     */
+    if (*URI == '.') {
+	val = xmlStrdup (URI);
+	goto done;
+    }
+
+    /*
+     * First parse URI into a standard form
+     */
+    ref = xmlCreateURI ();
+    if (ref == NULL)
+	return NULL;
+    ret = xmlParseURIReference (ref, (const char *) URI);
+    if (ret != 0)
+	goto done;		/* Error in URI, return NULL */
+
+    /*
+     * Next parse base into the same standard form
+     */
+    if ((base == NULL) || (*base == 0)) {
+	val = xmlStrdup (URI);
+	goto done;
+    }
+    bas = xmlCreateURI ();
+    if (bas == NULL)
+	goto done;
+    ret = xmlParseURIReference (bas, (const char *) base);
+    if (ret != 0)
+	goto done;		/* Error in base, return NULL */
+
+    /*
+     * If the scheme / server on the URI differs from the base,
+     * just return the URI
+     */
+    if ((ref->scheme != NULL) &&
+	  ((bas->scheme == NULL) ||
+	   xmlStrcmp ((xmlChar *)bas->scheme, (xmlChar *)ref->scheme) ||
+	   xmlStrcmp ((xmlChar *)bas->server, (xmlChar *)ref->server))) {
+	val = xmlStrdup (URI);
+	goto done;
+    }
+
+    /*
+     * At this point (at last!) we can compare the two paths
+     *
+     * First we compare the two strings and find where they first differ
+     */
+    bptr = (xmlChar *)bas->path;
+    if ((*bptr == '/') && (ref->path[0] != '/'))
+	bptr++;
+    while ((bptr[pos] == ref->path[pos]) && (bptr[pos] != 0))
+	pos++;
+
+    if (bptr[pos] == ref->path[pos]) {
+	val = NULL;		/* if no differences, return NULL */
+	goto done;		/* (I can't imagine why anyone would do this) */
+    }
+
+    /*
+     * In URI, "back up" to the last '/' encountered.  This will be the
+     * beginning of the "unique" suffix of URI
+     */
+    ix = pos;
+    if ((ref->path[ix] == '/') && (ix > 0))
+	ix--;
+    for (; ix > 0; ix--) {
+	if (ref->path[ix] == '/')
+	    break;
+    }
+    if (ix == 0)
+	uptr = (xmlChar *)ref->path;
+    else
+	uptr = (xmlChar *)&ref->path[ix + 1];
+
+    /*
+     * In base, count the number of '/' from the differing point
+     */
+    if (bptr[pos] != ref->path[pos]) {	/* check for trivial URI == base */
+	for (; bptr[ix] != 0; ix++) {
+	    if (bptr[ix] == '/')
+		nbslash++;
+	}
+    }
+
+    if (nbslash == 0) {
+	val = xmlStrdup (uptr);
+	goto done;
+    }
+    nbslash--;
+
+    /*
+     * Allocate just enough space for the returned string -
+     * length of the remainder of the URI, plus enough space
+     * for the "../" groups, plus one for the terminator
+     */
+    ix = xmlStrlen (uptr) + 1;
+    val = (xmlChar *) xmlMalloc (ix + 3 * nbslash);
+    if (val == NULL) {
+	goto done;
+    }
+    vptr = val;
+    /*
+     * Put in as many "../" as needed
+     */
+    for (; nbslash>0; nbslash--) {
+	*vptr++ = '.';
+	*vptr++ = '.';
+	*vptr++ = '/';
+    }
+    /*
+     * Finish up with the end of the URI
+     */
+    memcpy (vptr, uptr, ix);
+
+  done:
+    /*
+     * Free the working variables
+     */
+    if (ref != NULL)
+	xmlFreeURI (ref);
+    if (bas != NULL)
+	xmlFreeURI (bas);
+
+    return val;
+}
+
 /**
  * xmlCanonicPath:
  * @path:  the resource locator in a filesystem notation

xinclude.c

@@ -81,6 +81,7 @@ struct _xmlXIncludeCtxt {
     int              nbErrors; /* the number of errors detected */
     int                legacy; /* using XINCLUDE_OLD_NS */
     int            parseFlags; /* the flags used for parsing XML documents */
+    xmlChar *		 base; /* the current xml:base */
 };
 
 static int
@@ -677,6 +678,11 @@ xmlXIncludeRecurseDoc(xmlXIncludeCtxtPtr ctxt, xmlDocPtr doc,
 	newctxt->urlNr = ctxt->urlNr;
 	newctxt->urlTab = ctxt->urlTab;
 
+	/*
+	 * Inherit the existing base
+	 */
+	newctxt->base = ctxt->base;
+
 	/*
 	 * Inherit the documents already in use by other includes
 	 */
@@ -1631,12 +1637,26 @@ loaded:
      */
     if ((doc != NULL) && (URL != NULL) && (xmlStrchr(URL, (xmlChar) '/'))) {
 	xmlNodePtr node;
+	xmlChar *relURI;
 
-	node = ctxt->incTab[nr]->inc;
-	while (node != NULL) {
-	    if (node->type == XML_ELEMENT_NODE)
-		xmlNodeSetBase(node, URL);
-	    node = node->next;
+	/*
+	 * The base is only adjusted if necessary for the existing base
+	 */
+	relURI = xmlBuildRelativeURI(URL, ctxt->base);
+	if (relURI == NULL) {	/* Error return */
+	    xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref, 
+	               XML_XINCLUDE_HREF_URI,
+		       "trying to build relative URI from %s\n", URL);
+	} else {
+	    if (xmlStrchr(relURI, (xmlChar) '/')) {
+		node = ctxt->incTab[nr]->inc;
+		while (node != NULL) {
+	            if (node->type == XML_ELEMENT_NODE)
+			xmlNodeSetBase(node, relURI);
+	            node = node->next;
+		}
+	    }
+	    xmlFree(relURI);
 	}
     }
     if ((nr < ctxt->incNr) && (ctxt->incTab[nr]->doc != NULL) &&
@@ -1814,6 +1834,7 @@ xmlXIncludeLoadFallback(xmlXIncludeCtxtPtr ctxt, xmlNodePtr fallback, int nr) {
 	newctxt = xmlXIncludeNewContext(ctxt->doc);
 	if (newctxt == NULL)
 	    return (-1);
+	newctxt->base = ctxt->base;	/* Inherit the base from the existing context */
 	xmlXIncludeSetFlags(newctxt, ctxt->parseFlags);
 	ret = xmlXIncludeDoProcess(newctxt, ctxt->doc, fallback->children);
 	if (ctxt->nbErrors > 0)
@@ -1867,6 +1888,7 @@ xmlXIncludeLoadNode(xmlXIncludeCtxtPtr ctxt, int nr) {
     xmlChar *href;
     xmlChar *parse;
     xmlChar *base;
+    xmlChar *oldBase;
     xmlChar *URI;
     int xml = 1; /* default Issue 64 */
     int ret;
@@ -1947,14 +1969,23 @@ xmlXIncludeLoadNode(xmlXIncludeCtxtPtr ctxt, int nr) {
 #endif
 
     /*
-     * Cleanup
+     * Save the base for this include (saving the current one)
      */
+    oldBase = ctxt->base;
+    ctxt->base = base;
+
     if (xml) {
 	ret = xmlXIncludeLoadDoc(ctxt, URI, nr);
 	/* xmlXIncludeGetFragment(ctxt, cur, URI); */
     } else {
 	ret = xmlXIncludeLoadTxt(ctxt, URI, nr);
     }
+
+    /*
+     * Restore the original base before checking for fallback
+     */
+    ctxt->base = oldBase;
+    
     if (ret < 0) {
 	xmlNodePtr children;
 
@@ -2296,6 +2327,7 @@ xmlXIncludeProcessFlags(xmlDocPtr doc, int flags) {
     ctxt = xmlXIncludeNewContext(doc);
     if (ctxt == NULL)
 	return(-1);
+    ctxt->base = (xmlChar *)doc->URL;
     xmlXIncludeSetFlags(ctxt, flags);
     ret = xmlXIncludeDoProcess(ctxt, doc, tree);
     if ((ret >= 0) && (ctxt->nbErrors > 0))
@@ -2339,6 +2371,7 @@ xmlXIncludeProcessTreeFlags(xmlNodePtr tree, int flags) {
     ctxt = xmlXIncludeNewContext(tree->doc);
     if (ctxt == NULL)
 	return(-1);
+    ctxt->base = xmlNodeGetBase(tree->doc, tree);
     xmlXIncludeSetFlags(ctxt, flags);
     ret = xmlXIncludeDoProcess(ctxt, tree->doc, tree);
     if ((ret >= 0) && (ctxt->nbErrors > 0))