tree.c

Vovida 社区开源的 SIP 协议源码

/*
 * tree.c : implemetation of access function for an XML tree.
 *
 * See Copyright for the status of this software.
 *
 * [e-mail]
 */

#include "global.h"
#ifdef WIN32
#include "win32config.h"
#else
#include "config.h"
#endif

#include <stdio.h>
#include <string.h> /* for memset() only ! */

#ifdef HAVE_CTYPE_H
#include <ctype.h>
#endif
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#ifdef HAVE_ZLIB_H
#include <zlib.h>
#endif

#include <libxml/xmlmemory.h>
#include <libxml/tree.h>
#include <libxml/parser.h>
#include <libxml/entities.h>
#include <libxml/valid.h>

static xmlChar xmlStringText[] = { 't', 'e', 'x', 't', 0 };
static xmlChar xmlStringComment[] = { 'c', 'o', 'm', 'm', 'e', 'n', 't', 0 };
int oldXMLWDcompatibility = 0;
int xmlIndentTreeOutput = 0;
xmlBufferAllocationScheme xmlBufferAllocScheme = XML_BUFFER_ALLOC_EXACT;

static int xmlCompressMode = 0;
static int xmlCheckDTD = 1;
int xmlSaveNoEmptyTags = 0;

#define IS_BLANK(c)							\
  (((c) == '\n') || ((c) == '\r') || ((c) == '\t') || ((c) == ' '))

#define UPDATE_LAST_CHILD(n) if ((n) != NULL) {				\
    xmlNodePtr ulccur = (n)->children;					\
    if (ulccur == NULL) {						\
        (n)->last = NULL;						\
    } else {								\
        while (ulccur->next != NULL) ulccur = ulccur->next;		\
	(n)->last = ulccur;						\
}}

/* #define DEBUG_BUFFER */
/* #define DEBUG_TREE */

/************************************************************************
 *									*
 *		Allocation and deallocation of basic structures		*
 *									*
 ************************************************************************/
 
/**
 * xmlSetBufferAllocationScheme:
 * @scheme:  allocation method to use
 * 
 * Set the buffer allocation method.  Types are
 * XML_BUFFER_ALLOC_EXACT - use exact sizes, keeps memory usage down
 * XML_BUFFER_ALLOC_DOUBLEIT - double buffer when extra needed, 
 *                             improves performance
 */
void
xmlSetBufferAllocationScheme(xmlBufferAllocationScheme scheme) {
    xmlBufferAllocScheme = scheme;
}

/**
 * xmlGetBufferAllocationScheme:
 *
 * Types are
 * XML_BUFFER_ALLOC_EXACT - use exact sizes, keeps memory usage down
 * XML_BUFFER_ALLOC_DOUBLEIT - double buffer when extra needed, 
 *                             improves performance
 * 
 * Returns the current allocation scheme
 */
xmlBufferAllocationScheme
xmlGetBufferAllocationScheme() {
    return xmlBufferAllocScheme;
}

/**
 * xmlUpgradeOldNs:
 * @doc:  a document pointer
 * 
 * Upgrade old style Namespaces (PI) and move them to the root of the document.
 */
void
xmlUpgradeOldNs(xmlDocPtr doc) {
    xmlNsPtr cur;

    if ((doc == NULL) || (doc->oldNs == NULL)) return;
    if (doc->children == NULL) {
#ifdef DEBUG_TREE
        fprintf(stderr, "xmlUpgradeOldNs: failed no root !\n");
#endif
	return;
    }

    cur = doc->oldNs;
    while (cur->next != NULL) {
	cur->type = XML_LOCAL_NAMESPACE;
        cur = cur->next;
    }
    cur->type = XML_LOCAL_NAMESPACE;
    cur->next = doc->children->nsDef;
    doc->children->nsDef = doc->oldNs;
    doc->oldNs = NULL;
}

/**
 * xmlNewNs:
 * @node:  the element carrying the namespace
 * @href:  the URI associated
 * @prefix:  the prefix for the namespace
 *
 * Creation of a new Namespace. This function will refuse to create
 * a namespace with a similar prefix than an existing one present on this
 * node.
 * Returns returns a new namespace pointer or NULL
 */
xmlNsPtr
xmlNewNs(xmlNodePtr node, const xmlChar *href, const xmlChar *prefix) {
    xmlNsPtr cur;

    if (href == NULL) {
#ifdef DEBUG_TREE
        fprintf(stderr, "xmlNewNs: href == NULL !\n");
#endif
	return(NULL);
    }

    /*
     * Allocate a new Namespace and fill the fields.
     */
    cur = (xmlNsPtr) xmlMalloc(sizeof(xmlNs));
    if (cur == NULL) {
        fprintf(stderr, "xmlNewNs : malloc failed\n");
	return(NULL);
    }
    memset(cur, 0, sizeof(xmlNs));
    cur->type = XML_LOCAL_NAMESPACE;

    if (href != NULL)
	cur->href = xmlStrdup(href); 
    if (prefix != NULL)
	cur->prefix = xmlStrdup(prefix); 

    /*
     * Add it at the end to preserve parsing order ...
     * and checks for existing use of the prefix
     */
    if (node != NULL) {
	if (node->nsDef == NULL) {
	    node->nsDef = cur;
	} else {
	    xmlNsPtr prev = node->nsDef;

	    if (((prev->prefix == NULL) && (cur->prefix == NULL)) ||
		(!xmlStrcmp(prev->prefix, cur->prefix))) {
		xmlFreeNs(cur);
		return(NULL);
	    }    
	    while (prev->next != NULL) {
	        prev = prev->next;
		if (((prev->prefix == NULL) && (cur->prefix == NULL)) ||
		    (!xmlStrcmp(prev->prefix, cur->prefix))) {
		    xmlFreeNs(cur);
		    return(NULL);
		}    
	    }
	    prev->next = cur;
	}
    }
    return(cur);
}

/**
 * xmlNewGlobalNs:
 * @doc:  the document carrying the namespace
 * @href:  the URI associated
 * @prefix:  the prefix for the namespace
 *
 * Creation of a Namespace, the old way using PI and without scoping
 *   DEPRECATED !!!
 * It now create a namespace on the root element of the document if found.
 * Returns NULL this functionnality had been removed
 */
xmlNsPtr
xmlNewGlobalNs(xmlDocPtr doc, const xmlChar *href, const xmlChar *prefix) {
    xmlNodePtr root;

    xmlNsPtr cur;
 
    root = xmlDocGetRootElement(doc);
    if (root != NULL)
	return(xmlNewNs(root, href, prefix));
	
    /*
     * if there is no root element yet, create an old Namespace type
     * and it will be moved to the root at save time.
     */
    cur = (xmlNsPtr) xmlMalloc(sizeof(xmlNs));
    if (cur == NULL) {
        fprintf(stderr, "xmlNewGlobalNs : malloc failed\n");
	return(NULL);
    }
    memset(cur, 0, sizeof(xmlNs));
    cur->type = XML_GLOBAL_NAMESPACE;

    if (href != NULL)
	cur->href = xmlStrdup(href); 
    if (prefix != NULL)
	cur->prefix = xmlStrdup(prefix); 

    /*
     * Add it at the end to preserve parsing order ...
     */
    if (doc != NULL) {
	if (doc->oldNs == NULL) {
	    doc->oldNs = cur;
	} else {
	    xmlNsPtr prev = doc->oldNs;

	    while (prev->next != NULL) prev = prev->next;
	    prev->next = cur;
	}
    }

  return(NULL);
}

/**
 * xmlSetNs:
 * @node:  a node in the document
 * @ns:  a namespace pointer
 *
 * Associate a namespace to a node, a posteriori.
 */
void
xmlSetNs(xmlNodePtr node, xmlNsPtr ns) {
    if (node == NULL) {
#ifdef DEBUG_TREE
        fprintf(stderr, "xmlSetNs: node == NULL\n");
#endif
	return;
    }
    node->ns = ns;
}

/**
 * xmlFreeNs:
 * @cur:  the namespace pointer
 *
 * Free up the structures associated to a namespace
 */
void
xmlFreeNs(xmlNsPtr cur) {
    if (cur == NULL) {
#ifdef DEBUG_TREE
        fprintf(stderr, "xmlFreeNs : ns == NULL\n");
#endif
	return;
    }
    if (cur->href != NULL) xmlFree((char *) cur->href);
    if (cur->prefix != NULL) xmlFree((char *) cur->prefix);
    memset(cur, -1, sizeof(xmlNs));
    xmlFree(cur);
}

/**
 * xmlFreeNsList:
 * @cur:  the first namespace pointer
 *
 * Free up all the structures associated to the chained namespaces.
 */
void
xmlFreeNsList(xmlNsPtr cur) {
    xmlNsPtr next;
    if (cur == NULL) {
#ifdef DEBUG_TREE
        fprintf(stderr, "xmlFreeNsList : ns == NULL\n");
#endif
	return;
    }
    while (cur != NULL) {
        next = cur->next;
        xmlFreeNs(cur);
	cur = next;
    }
}

/**
 * xmlNewDtd:
 * @doc:  the document pointer
 * @name:  the DTD name
 * @ExternalID:  the external ID
 * @SystemID:  the system ID
 *
 * Creation of a new DTD for the external subset. To create an
 * internal subset, use xmlCreateIntSubset().
 *
 * Returns a pointer to the new DTD structure
 */
xmlDtdPtr
xmlNewDtd(xmlDocPtr doc, const xmlChar *name,
                    const xmlChar *ExternalID, const xmlChar *SystemID) {
    xmlDtdPtr cur;

    if ((doc != NULL) && (doc->extSubset != NULL)) {
#ifdef DEBUG_TREE
        fprintf(stderr, "xmlNewDtd(%s): document %s already have a DTD %s\n",
	    /* !!! */ (char *) name, doc->name,
	    /* !!! */ (char *)doc->extSubset->name);
#endif
	return(NULL);
    }

    /*
     * Allocate a new DTD and fill the fields.
     */
    cur = (xmlDtdPtr) xmlMalloc(sizeof(xmlDtd));
    if (cur == NULL) {
        fprintf(stderr, "xmlNewDtd : malloc failed\n");
	return(NULL);
    }
    memset(cur, 0 , sizeof(xmlDtd));
    cur->type = XML_DTD_NODE;

    if (name != NULL)
	cur->name = xmlStrdup(name); 
    if (ExternalID != NULL)
	cur->ExternalID = xmlStrdup(ExternalID); 
    if (SystemID != NULL)
	cur->SystemID = xmlStrdup(SystemID); 
    if (doc != NULL)
	doc->extSubset = cur;
    cur->doc = doc;

    return(cur);
}

/**
 * xmlGetIntSubset:
 * @doc:  the document pointer
 *
 * Get the internal subset of a document
 * Returns a pointer to the DTD structure or NULL if not found
 */

xmlDtdPtr
xmlGetIntSubset(xmlDocPtr doc) {
    xmlNodePtr cur;

    if (doc == NULL)
	return(NULL);
    cur = doc->children;
    while (cur != NULL) {
	if (cur->type == XML_DTD_NODE)
	    return((xmlDtdPtr) cur);
	cur = cur->next;
    }
    return((xmlDtdPtr) doc->intSubset);
}

/**
 * xmlCreateIntSubset:
 * @doc:  the document pointer
 * @name:  the DTD name
 * @ExternalID:  the external ID
 * @SystemID:  the system ID
 *
 * Create the internal subset of a document
 * Returns a pointer to the new DTD structure
 */
xmlDtdPtr
xmlCreateIntSubset(xmlDocPtr doc, const xmlChar *name,
                   const xmlChar *ExternalID, const xmlChar *SystemID) {
    xmlDtdPtr cur;

    if ((doc != NULL) && (xmlGetIntSubset(doc) != NULL)) {
#ifdef DEBUG_TREE
        fprintf(stderr, 
     "xmlCreateIntSubset(): document %s already have an internal subset\n",
	    doc->name);
#endif
	return(NULL);
    }

    /*
     * Allocate a new DTD and fill the fields.
     */
    cur = (xmlDtdPtr) xmlMalloc(sizeof(xmlDtd));
    if (cur == NULL) {
        fprintf(stderr, "xmlNewDtd : malloc failed\n");
	return(NULL);
    }
    memset(cur, 0, sizeof(xmlDtd));
    cur->type = XML_DTD_NODE;

    if (name != NULL)
	cur->name = xmlStrdup(name); 
    if (ExternalID != NULL)
	cur->ExternalID = xmlStrdup(ExternalID); 
    if (SystemID != NULL)
	cur->SystemID = xmlStrdup(SystemID); 
    if (doc != NULL) {
	doc->intSubset = cur;
	cur->parent = doc;
	cur->doc = doc;
	if (doc->children == NULL) {
	    doc->children = (xmlNodePtr) cur;
	    doc->last = (xmlNodePtr) cur;
	} else {
	    xmlNodePtr prev;

	    prev = doc->last;
	    prev->next = (xmlNodePtr) cur;
	    cur->prev = prev;
	    doc->last = (xmlNodePtr) cur;
	}
    }
    return(cur);
}

/**
 * xmlFreeDtd:
 * @cur:  the DTD structure to free up
 *
 * Free a DTD structure.
 */
void
xmlFreeDtd(xmlDtdPtr cur) {
    if (cur == NULL) {
#ifdef DEBUG_TREE
        fprintf(stderr, "xmlFreeDtd : DTD == NULL\n");
#endif
	return;
    }
    if (cur->children != NULL) {
	xmlNodePtr next, c = cur->children;

	/*
	 * Cleanup all the DTD comments they are not in the Dtd
	 * indexes.
	 */
        while (c != NULL) {
	    next = c->next;
	    if (c->type == XML_COMMENT_NODE) {
		xmlUnlinkNode(c);
		xmlFreeNode(c);
	    }
	    c = next;
	}
    }
    if (cur->name != NULL) xmlFree((char *) cur->name);
    if (cur->SystemID != NULL) xmlFree((char *) cur->SystemID);
    if (cur->ExternalID != NULL) xmlFree((char *) cur->ExternalID);
    /* TODO !!! */
    if (cur->notations != NULL)
        xmlFreeNotationTable((xmlNotationTablePtr) cur->notations);
    
    if (cur->elements != NULL)
        xmlFreeElementTable((xmlElementTablePtr) cur->elements);
    if (cur->attributes != NULL)
        xmlFreeAttributeTable((xmlAttributeTablePtr) cur->attributes);
    if (cur->entities != NULL)
        xmlFreeEntitiesTable((xmlEntitiesTablePtr) cur->entities);

    memset(cur, -1, sizeof(xmlDtd));
    xmlFree(cur);
}

/**
 * xmlNewDoc:
 * @version:  xmlChar string giving the version of XML "1.0"
 *
 * Returns a new document
 */
xmlDocPtr
xmlNewDoc(const xmlChar *version) {
    xmlDocPtr cur;

    if (version == NULL) {
#ifdef DEBUG_TREE
        fprintf(stderr, "xmlNewDoc : version == NULL\n");
#endif
	return(NULL);
    }

    /*
     * Allocate a new document and fill the fields.
     */
    cur = (xmlDocPtr) xmlMalloc(sizeof(xmlDoc));
    if (cur == NULL) {
        fprintf(stderr, "xmlNewDoc : malloc failed\n");
	return(NULL);
    }
    memset(cur, 0, sizeof(xmlDoc));
    cur->type = XML_DOCUMENT_NODE;

    cur->version = xmlStrdup(version); 
    cur->standalone = -1;
    cur->compression = -1; /* not initialized */
    cur->doc = cur;
    return(cur);
}

/**
 * xmlFreeDoc:
 * @cur:  pointer to the document
 * @:  
 *
 * Free up all the structures used by a document, tree included.
 */
void
xmlFreeDoc(xmlDocPtr cur) {
    if (cur == NULL) {
#ifdef DEBUG_TREE
        fprintf(stderr, "xmlFreeDoc : document == NULL\n");
#endif
	return;
    }
    if (cur->version != NULL) xmlFree((char *) cur->version);
    if (cur->name != NULL) xmlFree((char *) cur->name);