catalog.c

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    int fd;
#else
    FILE *fd;
#endif
    int len;
    long size;

#ifdef HAVE_STAT
    struct stat info;
#endif
    xmlChar *content;

    if (filename == NULL)
        return (NULL);

#ifdef HAVE_STAT
    if (stat(filename, &info) < 0)
        return (NULL);
#endif

#ifdef HAVE_STAT
    if ((fd = open(filename, O_RDONLY)) < 0)
#else
    if ((fd = fopen(filename, "rb")) == NULL)
#endif
    {
        return (NULL);
    }
#ifdef HAVE_STAT
    size = info.st_size;
#else
    if (fseek(fd, 0, SEEK_END) || (size = ftell(fd)) == EOF || fseek(fd, 0, SEEK_SET)) {        /* File operations denied? ok, just close and return failure */
        fclose(fd);
        return (NULL);
    }
#endif
    content = xmlMallocAtomic(size + 10);
    if (content == NULL) {
        xmlCatalogErrMemory("allocating catalog data");
        return (NULL);
    }
#ifdef HAVE_STAT
    len = read(fd, content, size);
#else
    len = fread(content, 1, size, fd);
#endif
    if (len < 0) {
        xmlFree(content);
        return (NULL);
    }
#ifdef HAVE_STAT
    close(fd);
#else
    fclose(fd);
#endif
    content[len] = 0;

    return(content);
}

/**
 * xmlCatalogNormalizePublic:
 * @pubID:  the public ID string
 *
 *  Normalizes the Public Identifier
 *
 * Implements 6.2. Public Identifier Normalization
 * from http://www.oasis-open.org/committees/entity/spec-2001-08-06.html
 *
 * Returns the new string or NULL, the string must be deallocated
 *         by the caller.
 */
static xmlChar *
xmlCatalogNormalizePublic(const xmlChar *pubID)
{
    int ok = 1;
    int white;
    const xmlChar *p;
    xmlChar *ret;
    xmlChar *q;

    if (pubID == NULL)
        return(NULL);

    white = 1;
    for (p = pubID;*p != 0 && ok;p++) {
        if (!xmlIsBlank_ch(*p))
            white = 0;
        else if (*p == 0x20 && !white)
            white = 1;
        else
            ok = 0;
    }
    if (ok && !white)	/* is normalized */
        return(NULL);

    ret = xmlStrdup(pubID);
    q = ret;
    white = 0;
    for (p = pubID;*p != 0;p++) {
        if (xmlIsBlank_ch(*p)) {
            if (q != ret)
                white = 1;
        } else {
            if (white) {
                *(q++) = 0x20;
                white = 0;
            }
            *(q++) = *p;
        }
    }
    *q = 0;
    return(ret);
}

/************************************************************************
 *									*
 *			The XML Catalog parser				*
 *									*
 ************************************************************************/

static xmlCatalogEntryPtr
xmlParseXMLCatalogFile(xmlCatalogPrefer prefer, const xmlChar *filename);
static void
xmlParseXMLCatalogNodeList(xmlNodePtr cur, xmlCatalogPrefer prefer,
	                   xmlCatalogEntryPtr parent, xmlCatalogEntryPtr cgroup);
static xmlChar *
xmlCatalogListXMLResolve(xmlCatalogEntryPtr catal, const xmlChar *pubID,
	              const xmlChar *sysID);
static xmlChar *
xmlCatalogListXMLResolveURI(xmlCatalogEntryPtr catal, const xmlChar *URI);


/**
 * xmlGetXMLCatalogEntryType:
 * @name:  the name
 *
 * lookup the internal type associated to an XML catalog entry name
 *
 * Returns the type associated with that name
 */
static xmlCatalogEntryType
xmlGetXMLCatalogEntryType(const xmlChar *name) {
    xmlCatalogEntryType type = XML_CATA_NONE;
    if (xmlStrEqual(name, (const xmlChar *) "system"))
	type = XML_CATA_SYSTEM;
    else if (xmlStrEqual(name, (const xmlChar *) "public"))
	type = XML_CATA_PUBLIC;
    else if (xmlStrEqual(name, (const xmlChar *) "rewriteSystem"))
	type = XML_CATA_REWRITE_SYSTEM;
    else if (xmlStrEqual(name, (const xmlChar *) "delegatePublic"))
	type = XML_CATA_DELEGATE_PUBLIC;
    else if (xmlStrEqual(name, (const xmlChar *) "delegateSystem"))
	type = XML_CATA_DELEGATE_SYSTEM;
    else if (xmlStrEqual(name, (const xmlChar *) "uri"))
	type = XML_CATA_URI;
    else if (xmlStrEqual(name, (const xmlChar *) "rewriteURI"))
	type = XML_CATA_REWRITE_URI;
    else if (xmlStrEqual(name, (const xmlChar *) "delegateURI"))
	type = XML_CATA_DELEGATE_URI;
    else if (xmlStrEqual(name, (const xmlChar *) "nextCatalog"))
	type = XML_CATA_NEXT_CATALOG;
    else if (xmlStrEqual(name, (const xmlChar *) "catalog"))
	type = XML_CATA_CATALOG;
    return(type);
}

/**
 * xmlParseXMLCatalogOneNode:
 * @cur:  the XML node
 * @type:  the type of Catalog entry
 * @name:  the name of the node
 * @attrName:  the attribute holding the value
 * @uriAttrName:  the attribute holding the URI-Reference
 * @prefer:  the PUBLIC vs. SYSTEM current preference value
 * @cgroup:  the group which includes this node
 *
 * Finishes the examination of an XML tree node of a catalog and build
 * a Catalog entry from it.
 *
 * Returns the new Catalog entry node or NULL in case of error.
 */
static xmlCatalogEntryPtr
xmlParseXMLCatalogOneNode(xmlNodePtr cur, xmlCatalogEntryType type,
			  const xmlChar *name, const xmlChar *attrName,
			  const xmlChar *uriAttrName, xmlCatalogPrefer prefer,
			  xmlCatalogEntryPtr cgroup) {
    int ok = 1;
    xmlChar *uriValue;
    xmlChar *nameValue = NULL;
    xmlChar *base = NULL;
    xmlChar *URL = NULL;
    xmlCatalogEntryPtr ret = NULL;

    if (attrName != NULL) {
	nameValue = xmlGetProp(cur, attrName);
	if (nameValue == NULL) {
	    xmlCatalogErr(ret, cur, XML_CATALOG_MISSING_ATTR,
			  "%s entry lacks '%s'\n", name, attrName, NULL);
	    ok = 0;
	}
    }
    uriValue = xmlGetProp(cur, uriAttrName);
    if (uriValue == NULL) {
	xmlCatalogErr(ret, cur, XML_CATALOG_MISSING_ATTR,
		"%s entry lacks '%s'\n", name, uriAttrName, NULL);
	ok = 0;
    }
    if (!ok) {
	if (nameValue != NULL)
	    xmlFree(nameValue);
	if (uriValue != NULL)
	    xmlFree(uriValue);
	return(NULL);
    }

    base = xmlNodeGetBase(cur->doc, cur);
    URL = xmlBuildURI(uriValue, base);
    if (URL != NULL) {
	if (xmlDebugCatalogs > 1) {
	    if (nameValue != NULL)
		xmlGenericError(xmlGenericErrorContext,
			"Found %s: '%s' '%s'\n", name, nameValue, URL);
	    else
		xmlGenericError(xmlGenericErrorContext,
			"Found %s: '%s'\n", name, URL);
	}
	ret = xmlNewCatalogEntry(type, nameValue, uriValue, URL, prefer, cgroup);
    } else {
	xmlCatalogErr(ret, cur, XML_CATALOG_ENTRY_BROKEN,
		"%s entry '%s' broken ?: %s\n", name, uriAttrName, uriValue);
    }
    if (nameValue != NULL)
	xmlFree(nameValue);
    if (uriValue != NULL)
	xmlFree(uriValue);
    if (base != NULL)
	xmlFree(base);
    if (URL != NULL)
	xmlFree(URL);
    return(ret);
}

/**
 * xmlParseXMLCatalogNode:
 * @cur:  the XML node
 * @prefer:  the PUBLIC vs. SYSTEM current preference value
 * @parent:  the parent Catalog entry
 * @cgroup:  the group which includes this node
 *
 * Examines an XML tree node of a catalog and build
 * a Catalog entry from it adding it to its parent. The examination can
 * be recursive.
 */
static void
xmlParseXMLCatalogNode(xmlNodePtr cur, xmlCatalogPrefer prefer,
	               xmlCatalogEntryPtr parent, xmlCatalogEntryPtr cgroup)
{
    xmlChar *uri = NULL;
    xmlChar *URL = NULL;
    xmlChar *base = NULL;
    xmlCatalogEntryPtr entry = NULL;

    if (cur == NULL)
        return;
    if (xmlStrEqual(cur->name, BAD_CAST "group")) {
        xmlChar *prop;
	xmlCatalogPrefer pref = XML_CATA_PREFER_NONE;

        prop = xmlGetProp(cur, BAD_CAST "prefer");
        if (prop != NULL) {
            if (xmlStrEqual(prop, BAD_CAST "system")) {
                prefer = XML_CATA_PREFER_SYSTEM;
            } else if (xmlStrEqual(prop, BAD_CAST "public")) {
                prefer = XML_CATA_PREFER_PUBLIC;
            } else {
		xmlCatalogErr(parent, cur, XML_CATALOG_PREFER_VALUE,
                              "Invalid value for prefer: '%s'\n",
			      prop, NULL, NULL);
            }
            xmlFree(prop);
	    pref = prefer;
        }
	prop = xmlGetProp(cur, BAD_CAST "id");
	base = xmlGetNsProp(cur, BAD_CAST "base", XML_XML_NAMESPACE);
	entry = xmlNewCatalogEntry(XML_CATA_GROUP, prop, base, NULL, pref, cgroup);
	xmlFree(prop);
    } else if (xmlStrEqual(cur->name, BAD_CAST "public")) {
	entry = xmlParseXMLCatalogOneNode(cur, XML_CATA_PUBLIC,
		BAD_CAST "public", BAD_CAST "publicId", BAD_CAST "uri", prefer, cgroup);
    } else if (xmlStrEqual(cur->name, BAD_CAST "system")) {
	entry = xmlParseXMLCatalogOneNode(cur, XML_CATA_SYSTEM,
		BAD_CAST "system", BAD_CAST "systemId", BAD_CAST "uri", prefer, cgroup);
    } else if (xmlStrEqual(cur->name, BAD_CAST "rewriteSystem")) {
	entry = xmlParseXMLCatalogOneNode(cur, XML_CATA_REWRITE_SYSTEM,
		BAD_CAST "rewriteSystem", BAD_CAST "systemIdStartString",
		BAD_CAST "rewritePrefix", prefer, cgroup);
    } else if (xmlStrEqual(cur->name, BAD_CAST "delegatePublic")) {
	entry = xmlParseXMLCatalogOneNode(cur, XML_CATA_DELEGATE_PUBLIC,
		BAD_CAST "delegatePublic", BAD_CAST "publicIdStartString",
		BAD_CAST "catalog", prefer, cgroup);
    } else if (xmlStrEqual(cur->name, BAD_CAST "delegateSystem")) {
	entry = xmlParseXMLCatalogOneNode(cur, XML_CATA_DELEGATE_SYSTEM,
		BAD_CAST "delegateSystem", BAD_CAST "systemIdStartString",
		BAD_CAST "catalog", prefer, cgroup);
    } else if (xmlStrEqual(cur->name, BAD_CAST "uri")) {
	entry = xmlParseXMLCatalogOneNode(cur, XML_CATA_URI,
		BAD_CAST "uri", BAD_CAST "name",
		BAD_CAST "uri", prefer, cgroup);
    } else if (xmlStrEqual(cur->name, BAD_CAST "rewriteURI")) {
	entry = xmlParseXMLCatalogOneNode(cur, XML_CATA_REWRITE_URI,
		BAD_CAST "rewriteURI", BAD_CAST "uriStartString",
		BAD_CAST "rewritePrefix", prefer, cgroup);
    } else if (xmlStrEqual(cur->name, BAD_CAST "delegateURI")) {
	entry = xmlParseXMLCatalogOneNode(cur, XML_CATA_DELEGATE_URI,
		BAD_CAST "delegateURI", BAD_CAST "uriStartString",
		BAD_CAST "catalog", prefer, cgroup);
    } else if (xmlStrEqual(cur->name, BAD_CAST "nextCatalog")) {
	entry = xmlParseXMLCatalogOneNode(cur, XML_CATA_NEXT_CATALOG,
		BAD_CAST "nextCatalog", NULL,
		BAD_CAST "catalog", prefer, cgroup);
    }
    if (entry != NULL) {
        if (parent != NULL) {
	    entry->parent = parent;
	    if (parent->children == NULL)
		parent->children = entry;
	    else {
		xmlCatalogEntryPtr prev;

		prev = parent->children;
		while (prev->next != NULL)
		    prev = prev->next;
		prev->next = entry;
	    }
	}
	if (entry->type == XML_CATA_GROUP) {
	    /*
	     * Recurse to propagate prefer to the subtree
	     * (xml:base handling is automated)
	     */
            xmlParseXMLCatalogNodeList(cur->children, prefer, parent, entry);
	}
    }
    if (base != NULL)
	xmlFree(base);
    if (uri != NULL)
	xmlFree(uri);
    if (URL != NULL)
	xmlFree(URL);
}

/**
 * xmlParseXMLCatalogNodeList:
 * @cur:  the XML node list of siblings
 * @prefer:  the PUBLIC vs. SYSTEM current preference value
 * @parent:  the parent Catalog entry
 * @cgroup:  the group which includes this list
 *
 * Examines a list of XML sibling nodes of a catalog and build
 * a list of Catalog entry from it adding it to the parent.
 * The examination will recurse to examine node subtrees.
 */
static void
xmlParseXMLCatalogNodeList(xmlNodePtr cur, xmlCatalogPrefer prefer,
	                   xmlCatalogEntryPtr parent, xmlCatalogEntryPtr cgroup) {
    while (cur != NULL) {
	if ((cur->ns != NULL) && (cur->ns->href != NULL) &&
	    (xmlStrEqual(cur->ns->href, XML_CATALOGS_NAMESPACE))) {
	    xmlParseXMLCatalogNode(cur, prefer, parent, cgroup);
	}
	cur = cur->next;
    }
    /* TODO: sort the list according to REWRITE lengths and prefer value */
}

/**
 * xmlParseXMLCatalogFile:
 * @prefer:  the PUBLIC vs. SYSTEM current preference value
 * @filename:  the filename for the catalog
 *
 * Parses the catalog file to extract the XML tree and then analyze the
 * tree to build a list of Catalog entries corresponding to this catalog
 * 
 * Returns the resulting Catalog entries list
 */
static xmlCatalogEntryPtr
xmlParseXMLCatalogFile(xmlCatalogPrefer prefer, const xmlChar *filename) {
    xmlDocPtr doc;
    xmlNodePtr cur;
    xmlChar *prop;
    xmlCatalogEntryPtr parent = NULL;

    if (filename == NULL)
        return(NULL);

    doc = xmlParseCatalogFile((const char *) filename);
    if (doc == NULL) {
	if (xmlDebugCatalogs)
	    xmlGenericError(xmlGenericErrorContext,
		    "Failed to parse catalog %s\n", filename);
	return(NULL);
    }

    if (xmlDebugCatalogs)
	xmlGenericError(xmlGenericErrorContext,
		"%d Parsing catalog %s\n", xmlGetThreadId(), filename);

    cur = xmlDocGetRootElement(doc);
    if ((cur != NULL) && (xmlStrEqual(cur->name, BAD_CAST "catalog")) &&
	(cur->ns != NULL) && (cur->ns->href != NULL) &&
	(xmlStrEqual(cur->ns->href, XML_CATALOGS_NAMESPACE))) {

	parent = xmlNewCatalogEntry(XML_CATA_CATALOG, NULL,
				    (const xmlChar *)filename, NULL, prefer, NULL);
        if (parent == NULL) {
	    xmlFreeDoc(doc);
	    return(NULL);
	}

	prop = xmlGetProp(cur, BAD_CAST "prefer");
	if (prop != NULL) {
	    if (xmlStrEqual(prop, BAD_CAST "system")) {
		prefer = XML_CATA_PREFER_SYSTEM;
	    } else if (xmlStrEqual(prop, BAD_CAST "public")) {
		prefer = XML_CATA_PREFER_PUBLIC;
	    } else {
		xmlCatalogErr(NULL, cur, XML_CATALOG_PREFER_VALUE,
			      "Invalid value for prefer: '%s'\n",
			      prop, NULL, NULL);
	    }
	    xmlFree(prop);
	}
	cur = cur->children;
	xmlParseXMLCatalogNodeList(cur, prefer, parent, NULL);
    } else {
	xmlCatalogErr(NULL, (xmlNodePtr) doc, XML_CATALOG_NOT_CATALOG,
		      "File %s is not an XML Catalog\n",
		      filename, NULL, NULL);
	xmlFreeDoc(doc);
	return(NULL);
    }
    xmlFreeDoc(doc);
    return(parent);
}

/**
 * xmlFetchXMLCatalogFile:
 * @catal:  an existing but incomplete catalog entry
 *
 * Fetch and parse the subcatalog referenced by an entry
 * 
 * Returns 0 in case of success, -1 otherwise
 */
static int
xmlFetchXMLCatalogFile(xmlCatalogEntryPtr catal) {
    xmlCatalogEntryPtr doc;

    if (catal == NULL) 
	return(-1);
    if (catal->URL == NULL)
	return(-1);
    if (catal->children != NULL)
	return(-1);

    /*
     * lock the whole catalog for modification
     */
    xmlRMutexLock(xmlCatalogMutex);
    if (catal->children != NULL) {
	/* Okay someone else did it in the meantime */
	xmlRMutexUnlock(xmlCatalogMutex);