path: root/ext/libxml/libxml.c

/*
   +----------------------------------------------------------------------+
   | PHP Version 5                                                        |
   +----------------------------------------------------------------------+
   | Copyright (c) 1997-2004 The PHP Group                                |
   +----------------------------------------------------------------------+
   | This source file is subject to version 3.0 of the PHP license,       |
   | that is bundled with this package in the file LICENSE, and is        |
   | available through the world-wide-web at the following url:           |
   | http://www.php.net/license/3_0.txt.                                  |
   | If you did not receive a copy of the PHP license and are unable to   |
   | obtain it through the world-wide-web, please send a note to          |
   | license@php.net so we can mail you a copy immediately.               |
   +----------------------------------------------------------------------+
   | Authors: Shane Caraveo <shane@php.net>                               |
   |          Wez Furlong <wez@thebrainroom.com>                          |
   +----------------------------------------------------------------------+
 */

/* $Id$ */

#define IS_EXT_MODULE

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include "php.h"

#define PHP_XML_INTERNAL
#include "zend_variables.h"
#include "ext/standard/php_string.h"
#include "ext/standard/info.h"
#include "ext/standard/file.h"

#if HAVE_LIBXML

#include <libxml/parser.h>
#include <libxml/parserInternals.h>
#include <libxml/tree.h>
#include <libxml/uri.h>
#include <libxml/xmlerror.h>
#ifdef LIBXML_SCHEMAS_ENABLED
#include <libxml/relaxng.h>
#endif

#include "php_libxml.h"

#define PHP_LIBXML_ERROR 0
#define PHP_LIBXML_CTX_ERROR 1
#define PHP_LIBXML_CTX_WARNING 2

/* a true global for initialization */
int _php_libxml_initialized = 0;

typedef struct _php_libxml_func_handler {
	php_libxml_export_node export_func;
} php_libxml_func_handler;

static HashTable php_libxml_exports;

#ifdef ZTS
int libxml_globals_id;
#else
PHP_LIBXML_API php_libxml_globals libxml_globals;
#endif

/* {{{ dynamically loadable module stuff */
#ifdef COMPILE_DL_LIBXML
ZEND_GET_MODULE(libxml)
# ifdef PHP_WIN32
# include "zend_arg_defs.c"
# endif
#endif /* COMPILE_DL_LIBXML */
/* }}} */

/* {{{ function prototypes */
PHP_MINIT_FUNCTION(libxml);
PHP_RINIT_FUNCTION(libxml);
PHP_MSHUTDOWN_FUNCTION(libxml);
PHP_RSHUTDOWN_FUNCTION(libxml);
PHP_MINFO_FUNCTION(libxml);

/* }}} */

/* {{{ extension definition structures */
function_entry libxml_functions[] = {
	PHP_FE(libxml_set_streams_context, NULL)
	{NULL, NULL, NULL}
};

zend_module_entry libxml_module_entry = {
    STANDARD_MODULE_HEADER,
	"libxml",                /* extension name */
	libxml_functions,        /* extension function list */
	PHP_MINIT(libxml),       /* extension-wide startup function */
	PHP_MSHUTDOWN(libxml),   /* extension-wide shutdown function */
	PHP_RINIT(libxml),       /* per-request startup function */
	PHP_RSHUTDOWN(libxml),   /* per-request shutdown function */
	PHP_MINFO(libxml),       /* information function */
    NO_VERSION_YET,
	STANDARD_MODULE_PROPERTIES
};

/* }}} */

/* {{{ internal functions for interoperability */
static int php_libxml_dec_node(php_libxml_node_ptr *nodeptr)
{
	int ret_refcount;

	ret_refcount = --nodeptr->refcount;
	if (ret_refcount == 0) {
		if (nodeptr->node != NULL && nodeptr->node->type != XML_DOCUMENT_NODE) {
			nodeptr->node->_private = NULL;
		}
		/* node is destroyed by another object. reset ret_refcount to 1 and node to NULL
		so the php_libxml_node_ptr is detroyed when the object is destroyed */
		nodeptr->refcount = 1;
		nodeptr->node = NULL;
	}

	return ret_refcount;
}

static int php_libxml_clear_object(php_libxml_node_object *object TSRMLS_DC)
{
	if (object->properties) {
		object->properties = NULL;
	}
	php_libxml_decrement_node_ptr(object TSRMLS_CC);
	return php_libxml_decrement_doc_ref(object TSRMLS_CC);
}

static int php_libxml_unregister_node(xmlNodePtr nodep TSRMLS_DC)
{
	php_libxml_node_object *wrapper;

	php_libxml_node_ptr *nodeptr = nodep->_private;

	if (nodeptr != NULL) {
		wrapper = nodeptr->_private;
		if (wrapper) {
			php_libxml_clear_object(wrapper TSRMLS_CC);
		} else {
			php_libxml_dec_node(nodeptr);
		}
	}

	return -1;
}

static void php_libxml_node_free(xmlNodePtr node)
{
	if(node) {
		if (node->_private != NULL) {
			((php_libxml_node_ptr *) node->_private)->node = NULL;
		}
		switch (node->type) {
			case XML_ATTRIBUTE_NODE:
				xmlFreeProp((xmlAttrPtr) node);
				break;
			case XML_ENTITY_DECL:
			case XML_ELEMENT_DECL:
			case XML_ATTRIBUTE_DECL:
				break;
			case XML_NOTATION_NODE:
				/* These require special handling */
				if (node->name != NULL) {
					xmlFree((char *) node->name);
				}
				if (((xmlEntityPtr) node)->ExternalID != NULL) {
					xmlFree((char *) ((xmlEntityPtr) node)->ExternalID);
				}
				if (((xmlEntityPtr) node)->SystemID != NULL) {
					xmlFree((char *) ((xmlEntityPtr) node)->SystemID);
				}
				xmlFree(node);
				break;
			case XML_NAMESPACE_DECL:
				if (node->ns) {
					xmlFreeNs(node->ns);
					node->ns = NULL;
				}
				node->type = XML_ELEMENT_NODE;
			default:
				xmlFreeNode(node);
		}
	}
}

static void php_libxml_node_free_list(xmlNodePtr node TSRMLS_DC)
{
	xmlNodePtr curnode;

	if (node != NULL) {
		curnode = node;
		while (curnode != NULL) {
			node = curnode;
			switch (node->type) {
				/* Skip property freeing for the following types */
				case XML_NOTATION_NODE:
					break;
				case XML_ENTITY_REF_NODE:
					php_libxml_node_free_list((xmlNodePtr) node->properties TSRMLS_CC);
					break;
				case XML_ATTRIBUTE_DECL:
				case XML_DTD_NODE:
				case XML_DOCUMENT_TYPE_NODE:
				case XML_ENTITY_DECL:
				case XML_ATTRIBUTE_NODE:
				case XML_NAMESPACE_DECL:
					php_libxml_node_free_list(node->children TSRMLS_CC);
					break;
				default:
					php_libxml_node_free_list(node->children TSRMLS_CC);
					php_libxml_node_free_list((xmlNodePtr) node->properties TSRMLS_CC);
			}

			curnode = node->next;
			xmlUnlinkNode(node);
			if (php_libxml_unregister_node(node TSRMLS_CC) == 0) {
				node->doc = NULL;
			}
			php_libxml_node_free(node);
		}
	}
}

/* }}} */

/* {{{ startup, shutdown and info functions */
#ifdef ZTS
static void php_libxml_init_globals(php_libxml_globals *libxml_globals_p TSRMLS_DC)
{
	LIBXML(stream_context) = NULL;
	LIBXML(error_buffer).c = NULL;
}
#endif

/* Channel libxml file io layer through the PHP streams subsystem.
 * This allows use of ftps:// and https:// urls */

int php_libxml_streams_IO_match_wrapper(const char *filename)
{
	TSRMLS_FETCH();

	if (zend_is_executing(TSRMLS_C)) {
		return php_stream_locate_url_wrapper(filename, NULL, 0 TSRMLS_CC) ? 1 : 0;
	}
	return 0;
}

void *php_libxml_streams_IO_open_wrapper(const char *filename, const char *mode, const int read_only)
{
	php_stream_statbuf ssbuf;
	php_stream_context *context = NULL;
	php_stream_wrapper *wrapper = NULL;
	char *resolved_path, *path_to_open = NULL;
	void *ret_val = NULL;

	TSRMLS_FETCH();
	resolved_path = xmlURIUnescapeString(filename, 0, NULL);

	if (resolved_path == NULL) {
		return NULL;
	}

	/* logic copied from _php_stream_stat, but we only want to fail
	   if the wrapper supports stat, otherwise, figure it out from
	   the open.  This logic is only to support hiding warnings
	   that the streams layer puts out at times, but for libxml we
	   may try to open files that don't exist, but it is not a failure
	   in xml processing (eg. DTD files)  */
	wrapper = php_stream_locate_url_wrapper(resolved_path, &path_to_open, ENFORCE_SAFE_MODE TSRMLS_CC);
	if (wrapper && read_only && wrapper->wops->url_stat) {
		if (wrapper->wops->url_stat(wrapper, path_to_open, 0, &ssbuf, NULL TSRMLS_CC) == -1) {
			xmlFree(resolved_path);
			return NULL;
		}
	}

	if (LIBXML(stream_context)) {
		context = zend_fetch_resource(&LIBXML(stream_context) TSRMLS_CC, -1, "Stream-Context", NULL, 1, php_le_stream_context());
		ret_val = php_stream_open_wrapper_ex(path_to_open, (char *)mode, ENFORCE_SAFE_MODE|REPORT_ERRORS, NULL, context);
		xmlFree(resolved_path);
		return ret_val;
	}
	ret_val = php_stream_open_wrapper(path_to_open, (char *)mode, ENFORCE_SAFE_MODE|REPORT_ERRORS, NULL);
	xmlFree(resolved_path);
	return ret_val;
}

void *php_libxml_streams_IO_open_read_wrapper(const char *filename)
{
	return php_libxml_streams_IO_open_wrapper(filename, "rb", 1);
}

void *php_libxml_streams_IO_open_write_wrapper(const char *filename)
{
	return php_libxml_streams_IO_open_wrapper(filename, "wb", 0);
}

int php_libxml_streams_IO_read(void *context, char *buffer, int len)
{
	TSRMLS_FETCH();
	return php_stream_read((php_stream*)context, buffer, len);
}

int php_libxml_streams_IO_write(void *context, const char *buffer, int len)
{
	TSRMLS_FETCH();
	return php_stream_write((php_stream*)context, buffer, len);
}

int php_libxml_streams_IO_close(void *context)
{
	TSRMLS_FETCH();
	return php_stream_close((php_stream*)context);
}

static void php_libxml_ctx_error_level(int level, void *ctx, const char *msg TSRMLS_DC)
{
	xmlParserCtxtPtr parser;

	parser = (xmlParserCtxtPtr) ctx;

	if (parser != NULL && parser->input != NULL) {
		if (parser->input->filename) {
			php_error_docref(NULL TSRMLS_CC, level, "%s in %s, line: %d", msg, parser->input->filename, parser->input->line);
		} else {
			php_error_docref(NULL TSRMLS_CC, level, "%s in Entity, line: %d", msg, parser->input->line);
		}
	}
}

static void php_libxml_internal_error_handler(int error_type, void *ctx, const char **msg, va_list ap)
{
	char *buf;
	int len, len_iter, output = 0;

	TSRMLS_FETCH();

	len = vspprintf(&buf, 0, *msg, ap);
	len_iter = len;

	/* remove any trailing \n */
	while (len_iter && buf[--len_iter] == '\n') {
		buf[len_iter] = '\0';
		output = 1;
	}

	smart_str_appendl(&LIBXML(error_buffer), buf, len);

	efree(buf);

	if (output == 1) {
		switch (error_type) {
			case PHP_LIBXML_CTX_ERROR:
				php_libxml_ctx_error_level(E_WARNING, ctx, LIBXML(error_buffer).c TSRMLS_CC);
				break;
			case PHP_LIBXML_CTX_WARNING:
				php_libxml_ctx_error_level(E_NOTICE, ctx, LIBXML(error_buffer).c TSRMLS_CC);
				break;
			default:
				php_error_docref(NULL TSRMLS_CC, E_WARNING, "%s", LIBXML(error_buffer).c);
		}
		smart_str_free(&LIBXML(error_buffer));
	}
}

void php_libxml_ctx_error(void *ctx, const char *msg, ...)
{
	va_list args;
	va_start(args, msg);
	php_libxml_internal_error_handler(PHP_LIBXML_CTX_ERROR, ctx, &msg, args);
	va_end(args);
}

void php_libxml_ctx_warning(void *ctx, const char *msg, ...)
{
	va_list args;
	va_start(args, msg);
	php_libxml_internal_error_handler(PHP_LIBXML_CTX_WARNING, ctx, &msg, args);
	va_end(args);
}

PHP_LIBXML_API void php_libxml_error_handler(void *ctx, const char *msg, ...)
{
	va_list args;
	va_start(args, msg);
	php_libxml_internal_error_handler(PHP_LIBXML_ERROR, ctx, &msg, args);
	va_end(args);
}


PHP_LIBXML_API void php_libxml_initialize() {
	if (!_php_libxml_initialized) {
		/* we should be the only one's to ever init!! */
		xmlInitParser();

		/* Enable php stream/wrapper support for libxml 
		   we only use php streams, so we do not enable
		   the default io handlers in libxml.
		*/
		xmlRegisterInputCallbacks(
			php_libxml_streams_IO_match_wrapper, 
			php_libxml_streams_IO_open_read_wrapper,
			php_libxml_streams_IO_read, 
			php_libxml_streams_IO_close);

		xmlRegisterOutputCallbacks(
			php_libxml_streams_IO_match_wrapper, 
			php_libxml_streams_IO_open_write_wrapper,
			php_libxml_streams_IO_write, 
			php_libxml_streams_IO_close);

		zend_hash_init(&php_libxml_exports, 0, NULL, NULL, 1);

		_php_libxml_initialized = 1;
	}
}

PHP_LIBXML_API void php_libxml_shutdown() {
	if (_php_libxml_initialized) {
#if defined(LIBXML_SCHEMAS_ENABLED)
		xmlRelaxNGCleanupTypes();
#endif
		xmlCleanupParser();
		zend_hash_destroy(&php_libxml_exports);
		_php_libxml_initialized = 0;
	}
}

PHP_MINIT_FUNCTION(libxml)
{
	php_libxml_initialize();

#ifdef ZTS
	ts_allocate_id(&libxml_globals_id, sizeof(php_libxml_globals), (ts_allocate_ctor) php_libxml_init_globals, NULL);
#else
	LIBXML(stream_context) = NULL;
	LIBXML(error_buffer).c = NULL;
#endif

	return SUCCESS;
}


PHP_RINIT_FUNCTION(libxml)
{
	/* report errors via handler rather than stderr */
	xmlSetGenericErrorFunc(NULL, php_libxml_error_handler);

    return SUCCESS;
}


PHP_MSHUTDOWN_FUNCTION(libxml)
{
	php_libxml_shutdown();

	return SUCCESS;
}


PHP_RSHUTDOWN_FUNCTION(libxml)
{
	/* reset libxml generic error handling */
	xmlSetGenericErrorFunc(NULL, NULL);

	smart_str_free(&LIBXML(error_buffer));
	return SUCCESS;
}


PHP_MINFO_FUNCTION(libxml)
{
	php_info_print_table_start();
	php_info_print_table_row(2, "libXML support", "active");
	php_info_print_table_row(2, "libXML Version", LIBXML_DOTTED_VERSION);
	php_info_print_table_row(2, "libXML streams", "enabled");
	php_info_print_table_end();
}
/* }}} */


/* {{{ proto void libxml_set_streams_context(resource streams_context) 
   Set the streams context for the next libxml document load or write */
PHP_FUNCTION(libxml_set_streams_context)
{
	zval *arg;

	if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "z", &arg) == FAILURE) {
		return;
	}
	if (LIBXML(stream_context)) {
		zval_ptr_dtor(&LIBXML(stream_context));
		LIBXML(stream_context) = NULL;
	}
	ZVAL_ADDREF(arg);
	LIBXML(stream_context) = arg;
}
/* }}} */


/* {{{ Common functions shared by extensions */
int php_libxml_xmlCheckUTF8(const unsigned char *s)
{
	int i;
	unsigned char c;

	for (i = 0; (c = s[i++]);) {
		if ((c & 0x80) == 0) {
		} else if ((c & 0xe0) == 0xc0) {
			if ((s[i++] & 0xc0) != 0x80) {
				return 0;
			}
		} else if ((c & 0xf0) == 0xe0) {
			if ((s[i++] & 0xc0) != 0x80 || (s[i++] & 0xc0) != 0x80) {
				return 0;
			}
		} else if ((c & 0xf8) == 0xf0) {
			if ((s[i++] & 0xc0) != 0x80 || (s[i++] & 0xc0) != 0x80 || (s[i++] & 0xc0) != 0x80) {
				return 0;
			}
		} else {
			return 0;
		}
	}
	return 1;
}

int php_libxml_register_export(zend_class_entry *ce, php_libxml_export_node export_function)
{
	php_libxml_func_handler export_hnd;
	
	/* Initialize in case this module hasnt been loaded yet */
	php_libxml_initialize();
	export_hnd.export_func = export_function;

    return zend_hash_add(&php_libxml_exports, ce->name, ce->name_length + 1, &export_hnd, sizeof(export_hnd), NULL);
}

PHP_LIBXML_API xmlNodePtr php_libxml_import_node(zval *object TSRMLS_DC)
{
	zend_class_entry *ce = NULL;
	xmlNodePtr node = NULL;
	php_libxml_func_handler *export_hnd;

	if (object->type == IS_OBJECT) {
		ce = Z_OBJCE_P(object);
		while (ce->parent != NULL) {
			ce = ce->parent;
		}
		if (zend_hash_find(&php_libxml_exports, ce->name, ce->name_length + 1, (void **) &export_hnd)  == SUCCESS) {
			node = export_hnd->export_func(object TSRMLS_CC);
		}
    }

	return node;

}

int php_libxml_increment_node_ptr(php_libxml_node_object *object, xmlNodePtr node, void *private_data TSRMLS_DC)
{
	int ret_refcount = -1;

	if (object != NULL && node != NULL) {
		if (object->node != NULL) {
			if (object->node->node == node) {
				return object->node->refcount;
			} else {
				php_libxml_decrement_node_ptr(object TSRMLS_CC);
			}
		}
		if (node->_private != NULL) {
			object->node = node->_private;
			ret_refcount = ++object->node->refcount;
			/* Only dom uses _private */
			if (object->node->_private == NULL) {
				object->node->_private = private_data;
			}
		} else {
			ret_refcount = 1;
			object->node = emalloc(sizeof(php_libxml_node_ptr));
			object->node->node = node;
			object->node->refcount = 1;
			object->node->_private = private_data;
			node->_private = object->node;
		}
	}

	return ret_refcount;
}

int php_libxml_decrement_node_ptr(php_libxml_node_object *object TSRMLS_DC) {
	int ret_refcount = -1;
	php_libxml_node_ptr *obj_node;

	if (object != NULL && object->node != NULL) {
		obj_node = (php_libxml_node_ptr *) object->node;
		ret_refcount = --obj_node->refcount;
		if (ret_refcount == 0) {
			if (obj_node->node != NULL) {
				obj_node->node->_private = NULL;
			}
			efree(obj_node);
		} 
		object->node = NULL;
	}

	return ret_refcount;
}

int php_libxml_increment_doc_ref(php_libxml_node_object *object, xmlDocPtr docp TSRMLS_DC) {
	int ret_refcount = -1;

	if (object->document != NULL) {
		object->document->refcount++;
		ret_refcount = object->document->refcount;
	} else if (docp != NULL) {
		ret_refcount = 1;
		object->document = emalloc(sizeof(php_libxml_ref_obj));
		object->document->ptr = docp;
		object->document->refcount = ret_refcount;
		object->document->doc_props = NULL;
	}

	return ret_refcount;
}

int php_libxml_decrement_doc_ref(php_libxml_node_object *object TSRMLS_DC) {
	int ret_refcount = -1;

	if (object != NULL && object->document != NULL) {
		ret_refcount = --object->document->refcount;
		if (ret_refcount == 0) {
			if (object->document->ptr != NULL) {
				xmlFreeDoc((xmlDoc *) object->document->ptr);
			}
			if (object->document->doc_props != NULL) {
				efree(object->document->doc_props);
			}
			efree(object->document);
		}
		object->document = NULL;
	}

	return ret_refcount;
}

void php_libxml_node_free_resource(xmlNodePtr node TSRMLS_DC)
{
	if (!node) {
		return;
	}

	switch (node->type) {
		case XML_DOCUMENT_NODE:
		case XML_HTML_DOCUMENT_NODE:
			break;
		default:
			if (node->parent == NULL || node->type == XML_NAMESPACE_DECL) {
				php_libxml_node_free_list((xmlNodePtr) node->children TSRMLS_CC);
				switch (node->type) {
					/* Skip property freeing for the following types */
					case XML_ATTRIBUTE_DECL:
					case XML_DTD_NODE:
					case XML_DOCUMENT_TYPE_NODE:
					case XML_ENTITY_DECL:
					case XML_ATTRIBUTE_NODE:
					case XML_NAMESPACE_DECL:
						break;
					default:
						php_libxml_node_free_list((xmlNodePtr) node->properties TSRMLS_CC);
				}
				if (php_libxml_unregister_node(node TSRMLS_CC) == 0) {
					node->doc = NULL;
				}
				php_libxml_node_free(node);
			} else {
				php_libxml_unregister_node(node TSRMLS_CC);
			}
	}
}

void php_libxml_node_decrement_resource(php_libxml_node_object *object TSRMLS_DC)
{
	int ret_refcount = -1;
	xmlNodePtr nodep;
	php_libxml_node_ptr *obj_node;

	if (object != NULL && object->node != NULL) {
		obj_node = (php_libxml_node_ptr *) object->node;
		nodep = object->node->node;
		ret_refcount = php_libxml_decrement_node_ptr(object TSRMLS_CC);
		if (ret_refcount == 0) {
			php_libxml_node_free_resource(nodep TSRMLS_CC);
		}
		/* Safe to call as if the resource were freed then doc pointer is NULL */
		php_libxml_decrement_doc_ref(object TSRMLS_CC);
	}
}
/* }}} */

#endif

/*
 * Local variables:
 * tab-width: 4
 * c-basic-offset: 4
 * End:
 * vim600: sw=4 ts=4 fdm=marker
 * vim<600: sw=4 ts=4
 */