Revamp the CHECKOUT method handling and various support functions for it. (548625d6) · Commits · CYBER - Cyber Security / TS 103 523 MSP / TLMSP / TLMSP Apache Httpd

modules/dav/fs/repos.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -594,8 +594,8 @@ static dav_error dav_fs_deleteset(apr_pool_t p, const dav_resource *resource)
		static dav_error * dav_fs_get_resource(
		request_rec *r,
		const char *root_dir,
		const char *target,
		int is_label,
		const char *label,
		int use_checked_in,
		dav_resource **result_resource)
		{
		dav_resource_private *ctx;

modules/dav/main/mod_dav.c

+121 −56

Original line number	Diff line number	Diff line
		@@ -346,6 +346,8 @@ static const char dav_cmd_davparam(cmd_parms cmd, void *config,
		** Send a nice response back to the user. In most cases, Apache doesn't
		** allow us to provide details in the body about what happened. This
		** function allows us to completely specify the response body.
		**
		** ### this function is not logging any errors! (e.g. the body)
		*/
		static int dav_error_response(request_rec r, int status, const char body)
		{
		@@ -614,35 +616,24 @@ static int dav_get_overwrite(request_rec *r)
		}

		/* resolve a request URI to a resource descriptor.
		* If target_allowed != 0, then allow the request target to be overridden
		* by either a DAV:version or DAV:label-name element (passed as
		* the target argument), or any Target-Selector header in the request.
		*
		* If label_allowed != 0, then allow the request target to be altered by
		* a Label: header.
		*
		* If use_checked_in is true, then the repository provider should return
		* the resource identified by the DAV:checked-in property of the resource
		* identified by the Request-URI.
		*/
		static dav_error * dav_get_resource(request_rec *r, int target_allowed,
		ap_xml_elem target, dav_resource *res_p)
		static dav_error * dav_get_resource(request_rec *r, int label_allowed,
		int use_checked_in, dav_resource **res_p)
		{
		void *data;
		dav_dir_conf *conf;
		const char *target_selector = NULL;
		int is_label = 0;
		int result;
		const char *label = NULL;
		dav_error *err;

		/* only look for the resource if it isn't already present */
		(void) apr_get_userdata(&data, DAV_KEY_RESOURCE, r->pool);
		if (data != NULL) {
		*res_p = data;
		return NULL;
		}

		/* if the request target can be overridden, get any target selector */
		if (target_allowed) {
		/* ### this should return a dav_error* */
		if ((result = dav_get_target_selector(r, target,
		&target_selector,
		&is_label)) != OK)
		return dav_new_error(r->pool, result, 0,
		"Could not process the method target.");
		if (label_allowed) {
		label = apr_table_get(r->headers_in, "label");
		}

		conf = ap_get_module_config(r->per_dir_config, &dav_module);
		@@ -650,7 +641,7 @@ static dav_error * dav_get_resource(request_rec *r, int target_allowed,

		/* resolve the resource */
		err = (*conf->provider->repos->get_resource)(r, conf->dir,
		target_selector, is_label,
		label, use_checked_in,
		res_p);
		if (err != NULL) {
		err = dav_push_error(r->pool, HTTP_INTERNAL_SERVER_ERROR, 0,
		@@ -668,9 +659,6 @@ static dav_error * dav_get_resource(request_rec *r, int target_allowed,
		ap_escape_html(r->pool, r->uri)));
		}

		(void) apr_set_userdata(*res_p, DAV_KEY_RESOURCE, apr_null_cleanup,
		r->pool);

		/* ### hmm. this doesn't feel like the right place or thing to do */
		/* if there were any input headers requiring a Vary header in the response,
		* add it now */
		@@ -736,7 +724,8 @@ static int dav_method_get(request_rec *r)
		* visible to Apache. We will fetch the resource from the repository,
		* then create a subrequest for Apache to handle.
		*/
		err = dav_get_resource(r, 1 /target_allowed/, NULL, &resource);
		err = dav_get_resource(r, 1 /* label_allowed /, 0 / use_checked_in */,
		&resource);
		if (err != NULL)
		return dav_handle_err(r, err, NULL);
		if (!resource->exists) {
		@@ -930,7 +919,8 @@ static int dav_method_post(request_rec *r)
		dav_error *err;

		/* Ask repository module to resolve the resource */
		err = dav_get_resource(r, 0 /target_allowed/, NULL, &resource);
		err = dav_get_resource(r, 0 /* label_allowed /, 0 / use_checked_in */,
		&resource);
		if (err != NULL)
		return dav_handle_err(r, err, NULL);

		@@ -967,7 +957,8 @@ static int dav_method_put(request_rec *r)
		}

		/* Ask repository module to resolve the resource */
		err = dav_get_resource(r, 0 /target_allowed/, NULL, &resource);
		err = dav_get_resource(r, 0 /* label_allowed /, 0 / use_checked_in */,
		&resource);
		if (err != NULL)
		return dav_handle_err(r, err, NULL);

		@@ -1181,7 +1172,8 @@ static int dav_method_delete(request_rec *r)
		}

		/* Ask repository module to resolve the resource */
		err = dav_get_resource(r, 0 /target_allowed/, NULL, &resource);
		err = dav_get_resource(r, 0 /* label_allowed /, 0 / use_checked_in */,
		&resource);
		if (err != NULL)
		return dav_handle_err(r, err, NULL);
		if (!resource->exists) {
		@@ -1538,7 +1530,8 @@ static int dav_method_options(request_rec *r)
		dav_error *err;

		/* resolve the resource */
		err = dav_get_resource(r, 0 /target_allowed/, NULL, &resource);
		err = dav_get_resource(r, 0 /* label_allowed /, 0 / use_checked_in */,
		&resource);
		if (err != NULL)
		return dav_handle_err(r, err, NULL);

		@@ -1890,7 +1883,8 @@ static int dav_method_propfind(request_rec *r)
		dav_response *multi_status;

		/* Ask repository module to resolve the resource */
		err = dav_get_resource(r, 1 /target_allowed/, NULL, &resource);
		err = dav_get_resource(r, 1 /* label_allowed /, 0 / use_checked_in */,
		&resource);
		if (err != NULL)
		return dav_handle_err(r, err, NULL);

		@@ -2154,7 +2148,8 @@ static int dav_method_proppatch(request_rec *r)
		dav_prop_ctx *ctx;

		/* Ask repository module to resolve the resource */
		err = dav_get_resource(r, 0 /target_allowed/, NULL, &resource);
		err = dav_get_resource(r, 0 /* label_allowed /, 0 / use_checked_in */,
		&resource);
		if (err != NULL)
		return dav_handle_err(r, err, NULL);
		if (!resource->exists) {
		@@ -2354,7 +2349,8 @@ static int dav_method_mkcol(request_rec *r)
		&dav_module);

		/* Ask repository module to resolve the resource */
		err = dav_get_resource(r, 0 /target_allowed/, NULL, &resource);
		err = dav_get_resource(r, 0 /* label_allowed /, 0 / use_checked_in */,
		&resource);
		if (err != NULL)
		return dav_handle_err(r, err, NULL);

		@@ -2473,7 +2469,8 @@ static int dav_method_copymove(request_rec *r, int is_move)
		int resource_state;

		/* Ask repository module to resolve the resource */
		err = dav_get_resource(r, !is_move /target_allowed/, NULL, &resource);
		err = dav_get_resource(r, !is_move /* label_allowed */,
		0 /* use_checked_in */, &resource);
		if (err != NULL)
		return dav_handle_err(r, err, NULL);
		if (!resource->exists) {
		@@ -2527,7 +2524,8 @@ static int dav_method_copymove(request_rec *r, int is_move)
		}

		/* Resolve destination resource */
		err = dav_get_resource(lookup.rnew, 0 /target_allowed/, NULL, &resnew);
		err = dav_get_resource(lookup.rnew, 0 /* label_allowed */,
		0 /* use_checked_in */, &resnew);
		if (err != NULL)
		return dav_handle_err(r, err, NULL);

		@@ -2856,7 +2854,9 @@ static int dav_method_lock(request_rec *r)
		* so allow it, and let provider reject the lock attempt
		* on a version if it wants to.
		*/
		err = dav_get_resource(r, 1 /target_allowed/, NULL, &resource);
		/* ### gjs: I'm not sure we want to allow for locking a version... */
		err = dav_get_resource(r, 1 /* label_allowed /, 0 / use_checked_in */,
		&resource);
		if (err != NULL)
		return dav_handle_err(r, err, NULL);

		@@ -3043,7 +3043,9 @@ static int dav_method_unlock(request_rec *r)
		* so allow it, and let provider reject the unlock attempt
		* on a version if it wants to.
		*/
		err = dav_get_resource(r, 1 /target_allowed/, NULL, &resource);
		/* ### gjs: I'm not sure we want to allow for locking a version... */
		err = dav_get_resource(r, 1 /* label_allowed /, 0 / use_checked_in */,
		&resource);
		if (err != NULL)
		return dav_handle_err(r, err, NULL);

		@@ -3101,7 +3103,8 @@ static int dav_method_vsn_control(request_rec *r)
		return DECLINED;

		/* ask repository module to resolve the resource */
		err = dav_get_resource(r, 0 /target_allowed/, NULL, &resource);
		err = dav_get_resource(r, 0 /* label_allowed /, 0 / use_checked_in */,
		&resource);
		if (err != NULL)
		return dav_handle_err(r, err, NULL);

		@@ -3279,7 +3282,11 @@ static int dav_method_checkout(request_rec *r)
		dav_error *err;
		int result;
		ap_xml_doc *doc;
		ap_xml_elem *target = NULL;
		int apply_to_vsn = 0;
		int is_unreserved = 0;
		int is_fork_ok = 0;
		int create_activity = 0;
		apr_array_header_t *activities = NULL;

		/* If no versioning provider, decline the request */
		if (vsn_hooks == NULL)
		@@ -3289,6 +3296,8 @@ static int dav_method_checkout(request_rec *r)
		return result;

		if (doc != NULL) {
		const ap_xml_elem *aset;

		if (!dav_validate_root(doc, "checkout")) {
		/* This supplies additional information for the default msg. */
		ap_log_rerror(APLOG_MARK, APLOG_ERR \| APLOG_NOERRNO, 0, r,
		@@ -3297,12 +3306,57 @@ static int dav_method_checkout(request_rec *r)
		return HTTP_BAD_REQUEST;
		}

		if ((target = dav_find_child(doc->root, "version")) == NULL)
		target = dav_find_child(doc->root, "label-name");
		if (dav_find_child(doc->root, "apply-to-version") != NULL) {
		if (apr_table_get(r->headers_in, "label") != NULL) {
		/* ### we want generic 403/409 XML reporting here */
		/* ### DAV:must-not-have-label-and-apply-to-version */
		return dav_error_response(r, HTTP_CONFLICT,
		"DAV:apply-to-version cannot be "
		"used in conjunction with a "
		"Label header.");
		}
		apply_to_vsn = 1;
		}

		is_unreserved = dav_find_child(doc->root, "unreserved") != NULL;
		is_fork_ok = dav_find_child(doc->root, "fork-ok") != NULL;

		if ((aset = dav_find_child(doc->root, "activity-set")) != NULL) {
		if (dav_find_child(aset, "new") != NULL) {
		create_activity = 1;
		}
		else {
		const ap_xml_elem *child = aset->first_child;

		for (; child != NULL; child = child->next) {
		if (child->ns == AP_XML_NS_DAV_ID
		&& strcmp(child->name, "href") == 0) {
		const char *href;

		href = dav_xml_get_cdata(child, r->pool,
		1 /* strip_white */);
		(const char *)apr_push_array(activities) = href;
		}
		}

		if (activities->nelts == 0) {
		/* no href's is a DTD violation:
		<!ELEMENT activity-set (href+ \| new)>
		*/

		/* This supplies additional info for the default msg. */
		ap_log_rerror(APLOG_MARK, APLOG_ERR \| APLOG_NOERRNO, 0, r,
		"Within the DAV:activity-set element, the "
		"DAV:new element must be used, or at least "
		"one DAV:href must be specified.");
		return HTTP_BAD_REQUEST;
		}
		}
		}
		}

		/* Ask repository module to resolve the resource */
		err = dav_get_resource(r, 1 /target_allowed/, target, &resource);
		err = dav_get_resource(r, 1 /label_allowed/, apply_to_vsn, &resource);
		if (err != NULL)
		return dav_handle_err(r, err, NULL);
		if (!resource->exists) {
		@@ -3331,7 +3385,9 @@ static int dav_method_checkout(request_rec *r)
		/* ### do lock checks, once behavior is defined */

		/* Do the checkout */
		if ((err = (*vsn_hooks->checkout)(resource, &working_resource)) != NULL) {
		if ((err = (*vsn_hooks->checkout)(resource, is_unreserved, is_fork_ok,
		create_activity, activities,
		&working_resource)) != NULL) {
		err = dav_push_error(r->pool, HTTP_CONFLICT, 0,
		apr_psprintf(r->pool,
		"Could not CHECKOUT resource %s.",
		@@ -3367,7 +3423,8 @@ static int dav_method_uncheckout(request_rec *r)
		}

		/* Ask repository module to resolve the resource */
		err = dav_get_resource(r, 0 /target_allowed/, NULL, &resource);
		err = dav_get_resource(r, 0 /* label_allowed /, 0 / use_checked_in */,
		&resource);
		if (err != NULL)
		return dav_handle_err(r, err, NULL);
		if (!resource->exists) {
		@@ -3430,7 +3487,8 @@ static int dav_method_checkin(request_rec *r)
		}

		/* Ask repository module to resolve the resource */
		err = dav_get_resource(r, 0 /* target_allowed */, NULL, &resource);
		err = dav_get_resource(r, 0 /* label_allowed /, 0 / use_checked_in */,
		&resource);
		if (err != NULL)
		return dav_handle_err(r, err, NULL);
		if (!resource->exists) {
		@@ -3536,7 +3594,8 @@ static int dav_method_set_target(request_rec *r)
		return DECLINED;

		/* Ask repository module to resolve the resource */
		err = dav_get_resource(r, 0 /target_allowed/, NULL, &resource);
		err = dav_get_resource(r, 0 /* label_allowed /, 0 / use_checked_in */,
		&resource);
		if (err != NULL)
		return dav_handle_err(r, err, NULL);
		if (!resource->exists) {
		@@ -3718,7 +3777,8 @@ static int dav_method_label(request_rec *r)
		return DECLINED;

		/* Ask repository module to resolve the resource */
		err = dav_get_resource(r, 1 /target_allowed/, NULL, &resource);
		err = dav_get_resource(r, 1 /* label_allowed /, 0 / use_checked_in */,
		&resource);
		if (err != NULL)
		return dav_handle_err(r, err, NULL);
		if (!resource->exists) {
		@@ -3829,7 +3889,7 @@ static int dav_method_report(request_rec *r)
		dav_resource *resource;
		const dav_hooks_vsn *vsn_hooks = DAV_GET_HOOKS_VSN(r);
		int result;
		int target_allowed;
		int label_allowed;
		ap_xml_doc *doc;
		ap_text_header hdr = { 0 };
		ap_text *t;
		@@ -3852,8 +3912,9 @@ static int dav_method_report(request_rec *r)
		* First determine whether a Target-Selector header is allowed
		* for this report.
		*/
		target_allowed = (*vsn_hooks->report_target_selector_allowed)(doc);
		err = dav_get_resource(r, target_allowed, NULL, &resource);
		label_allowed = (*vsn_hooks->report_target_selector_allowed)(doc);
		err = dav_get_resource(r, label_allowed, 0 /* use_checked_in */,
		&resource);
		if (err != NULL)
		return dav_handle_err(r, err, NULL);
		if (!resource->exists) {
		@@ -3900,7 +3961,8 @@ static int dav_method_make_workspace(request_rec *r)
		return DECLINED;

		/* ask repository module to resolve the resource */
		err = dav_get_resource(r, 0 /target_allowed/, NULL, &resource);
		err = dav_get_resource(r, 0 /* label_allowed /, 0 / use_checked_in */,
		&resource);
		if (err != NULL)
		return dav_handle_err(r, err, NULL);

		@@ -3963,7 +4025,8 @@ static int dav_method_make_activity(request_rec *r)
		return DECLINED;

		/* ask repository module to resolve the resource */
		err = dav_get_resource(r, 0 /target_allowed/, NULL, &resource);
		err = dav_get_resource(r, 0 /* label_allowed /, 0 / use_checked_in */,
		&resource);
		if (err != NULL)
		return dav_handle_err(r, err, NULL);

		@@ -4034,7 +4097,8 @@ static int dav_method_bind(request_rec *r)
		return DECLINED;

		/* Ask repository module to resolve the resource */
		err = dav_get_resource(r, 0 /!target_allowed/, NULL, &resource);
		err = dav_get_resource(r, 0 /* label_allowed /, 0 / use_checked_in */,
		&resource);
		if (err != NULL)
		return dav_handle_err(r, err, NULL);
		if (!resource->exists) {
		@@ -4081,7 +4145,8 @@ static int dav_method_bind(request_rec *r)
		}

		/* resolve binding resource */
		err = dav_get_resource(lookup.rnew, 0 /!target_allowed/, NULL, &binding);
		err = dav_get_resource(lookup.rnew, 0 /* label_allowed */,
		0 /* use_checked_in */, &binding);
		if (err != NULL)
		return dav_handle_err(r, err, NULL);

modules/dav/main/mod_dav.h

+32 −31

Original line number	Diff line number	Diff line
		@@ -59,11 +59,13 @@
		#ifndef _MOD_DAV_H_
		#define _MOD_DAV_H_

		#include "httpd.h"
		#include "util_xml.h"
		#include "apr_hooks.h"
		#include "apr_hash.h"
		#include "apr_dbm.h"
		#include "apr_tables.h"

		#include "httpd.h"
		#include "util_xml.h"

		#include <limits.h> /* for INT_MAX */

		@@ -519,6 +521,10 @@ int dav_get_depth(request_rec *r, int def_depth);
		int dav_validate_root(const ap_xml_doc doc, const char tagname);
		ap_xml_elem dav_find_child(const ap_xml_elem elem, const char *tagname);

		/* gather up all the CDATA into a single string */
		const char dav_xml_get_cdata(const ap_xml_elem elem, apr_pool_t *pool,
		int strip_white);


		/* --------------------------------------------------------------------
		**
		@@ -599,9 +605,6 @@ APR_DECLARE_EXTERNAL_HOOK(dav, DAV, void, insert_all_liveprops,
		(request_rec r, const dav_resource resource,
		dav_prop_insert what, ap_text_header *phdr))

		/* ### make this internal to mod_dav.c ? */
		#define DAV_KEY_RESOURCE "dav-resource"

		const dav_hooks_locks dav_get_lock_hooks(request_rec r);
		const dav_hooks_propdb dav_get_propdb_hooks(request_rec r);
		const dav_hooks_vsn dav_get_vsn_hooks(request_rec r);
		@@ -1573,11 +1576,17 @@ struct dav_hooks_repository
		* URI or accessing the resource or whatever, then an error should be
		* returned.
		*
		* root_dir: the root of the directory for which this repository is
		* configured.
		* target: is either a label, or a version URI, or NULL. If there is
		* a target, then is_label specifies whether the target is a
		* label or a URI.
		* root_dir:
		* the root of the directory for which this repository is configured.
		*
		* label:
		* if a Label: header is present (and allowed), this is the label
		* to use to identify a version resource from the resource's
		* corresponding version history. Otherwise, it will be NULL.
		*
		* use_checked_in:
		* use the DAV:checked-in property of the resource identified by the
		* Request-URI to identify and return a version resource
		*
		* The provider may associate the request storage pool with the resource
		* (in the resource->pool field), to use in other operations on that
		@@ -1586,8 +1595,8 @@ struct dav_hooks_repository
		dav_error * (*get_resource)(
		request_rec *r,
		const char *root_dir,
		const char *target,
		int is_label,
		const char *label,
		int use_checked_in,
		dav_resource **resource
		);

		@@ -1786,25 +1795,6 @@ struct dav_hooks_repository
		*/


		/*
		* dav_get_target_selector
		*
		* If a DAV:version or DAV:label-name element is provided,
		* then it is assumed to provide the target version.
		* If no element is provided (version==NULL), then the
		* request headers are examined for a Target-Selector header.
		*
		* The target version, if any, is then returned. If the version
		* was specified by a label, then *is_label is set to 1.
		* Otherwise, the target is a version URI.
		*
		* (used by versioning clients)
		*/
		int dav_get_target_selector(request_rec *r,
		const ap_xml_elem *version,
		const char **target,
		int *is_label);

		/* dav_add_vary_header
		*
		* If there were any headers in the request which require a Vary header
		@@ -1925,8 +1915,19 @@ struct dav_hooks_vsn
		* resource descriptor will refer to the working resource.
		* The working_resource argument can be NULL if the caller
		* is not interested in the working resource.
		*
		* If the client has specified DAV:unreserved or DAV:fork-ok in the
		* checkout request, then the corresponding flags are set. If
		* DAV:activity-set has been specified, then create_activity is set
		* if DAV:new was specified; otherwise, the DAV:href elements' CDATA
		* (the actual href text) is passed in the "activities" array (each
		* element of the array is a const char *). activities will be NULL
		* no DAV:activity-set was provided or when create_activity is set.
		*/
		dav_error * (checkout)(dav_resource resource,
		int is_unreserved, int is_fork_ok,
		int create_activity,
		apr_array_header_t *activities,
		dav_resource **working_resource);

		/* Uncheckout a resource. If successful, the resource

modules/dav/main/util.c

+68 −51

Original line number	Diff line number	Diff line
		@@ -305,6 +305,61 @@ ap_xml_elem dav_find_child(const ap_xml_elem elem, const char *tagname)
		return NULL;
		}

		/* gather up all the CDATA into a single string */
		const char dav_xml_get_cdata(const ap_xml_elem elem, apr_pool_t *pool,
		int strip_white)
		{
		apr_size_t len = 0;
		ap_text *scan;
		const ap_xml_elem *child;
		char *cdata;
		char *s;
		apr_size_t tlen;

		for (scan = elem->first_cdata.first; scan != NULL; scan = scan->next)
		len += strlen(scan->text);

		for (child = elem->first_child; child != NULL; child = child->next) {
		for (scan = child->following_cdata.first;
		scan != NULL;
		scan = scan->next)
		len += strlen(scan->text);
		}

		cdata = s = apr_palloc(pool, len + 1);

		for (scan = elem->first_cdata.first; scan != NULL; scan = scan->next) {
		tlen = strlen(scan->text);
		memcpy(s, scan->text, tlen);
		s += tlen;
		}

		for (child = elem->first_child; child != NULL; child = child->next) {
		for (scan = child->following_cdata.first;
		scan != NULL;
		scan = scan->next) {
		tlen = strlen(scan->text);
		memcpy(s, scan->text, tlen);
		s += tlen;
		}
		}

		*s = '\0';

		if (strip_white && len > 0) {
		/* trim leading whitespace */
		while (apr_isspace(cdata)) / assume: return false for '\0' */
		++cdata;

		/* trim trailing whitespace */
		while (len-- > 0 && apr_isspace(cdata[len]))
		continue;
		cdata[len + 1] = '\0';
		}

		return cdata;
		}

		/* ---------------------------------------------------------------
		**
		** Timeout header processing
		@@ -1492,6 +1547,8 @@ dav_error * dav_get_locktoken_list(request_rec r, dav_locktoken_list *ltl)
		return NULL;
		}

		#if 0 /* not needed right now... */

		static const char strip_white(const char s, apr_pool_t *pool)
		{
		apr_size_t idx;
		@@ -1513,53 +1570,9 @@ static const char strip_white(const char s, apr_pool_t *pool)

		return s;
		}
		#endif

		#define DAV_TARGET_SELECTOR_HDR "Target-Selector"

		/* see mod_dav.h for docco */
		int dav_get_target_selector(request_rec *r,
		const ap_xml_elem *version,
		const char **target,
		int *is_label)
		{
		/* Initialize results */
		*target = NULL;
		*is_label = 0;

		if (version != NULL) {
		/* Expect either <DAV:version><DAV:href>URI</DAV:href></DAV:version>
		* or <DAV:label-name>LABEL</DAV:label-name> */
		if (strcmp(version->name, "version") == 0) {
		if ((version = dav_find_child(version, "href")) == NULL) {
		ap_log_rerror(APLOG_MARK, APLOG_ERR \| APLOG_NOERRNO, 0, r,
		"Missing DAV:href in DAV:version element");
		return HTTP_BAD_REQUEST;
		}

		/* return the contents of the DAV:href element */
		/* ### this presumes no child elements */
		*target = strip_white(version->first_cdata.first->text, r->pool);
		}
		else if (strcmp(version->name, "label-name") == 0) {
		/* return contents of the DAV:label-name element */
		*target = strip_white(version->first_cdata.first->text, r->pool);
		*is_label = 1;
		}
		else {
		ap_log_rerror(APLOG_MARK, APLOG_ERR \| APLOG_NOERRNO, 0, r,
		"Unknown version specifier (not DAV:version or DAV:label-name)");
		return HTTP_BAD_REQUEST;
		}
		}
		else {
		/* no element. see if a Target-Selector header was provided
		* (which is always interpreted as a label) */
		*target = apr_table_get(r->headers_in, DAV_TARGET_SELECTOR_HDR);
		*is_label = 1;
		}

		return OK;
		}
		#define DAV_LABEL_HDR "Label"

		/* dav_add_vary_header
		*
		@@ -1572,18 +1585,22 @@ void dav_add_vary_header(request_rec *in_req,
		{
		const dav_hooks_vsn *vsn_hooks = DAV_GET_HOOKS_VSN(in_req);

		/* ### this is probably all wrong... I think there is a function in
		### the Apache API to add things to the Vary header. need to check */

		/* Only versioning headers require a Vary response header,
		* so only do this check if there is a versioning provider */
		if (vsn_hooks != NULL) {
		const char *target = apr_table_get(in_req->headers_in, DAV_TARGET_SELECTOR_HDR);
		const char *target = apr_table_get(in_req->headers_in, DAV_LABEL_HDR);
		const char *vary = apr_table_get(out_req->headers_out, "Vary");

		/* If Target-Selector specified, add it to the Vary header */
		if (target != NULL) {
		if (vary == NULL)
		vary = DAV_TARGET_SELECTOR_HDR;
		vary = DAV_LABEL_HDR;
		else
		vary = apr_pstrcat(out_req->pool, vary, "," DAV_TARGET_SELECTOR_HDR, NULL);
		vary = apr_pstrcat(out_req->pool, vary, "," DAV_LABEL_HDR,
		NULL);

		apr_table_setn(out_req->headers_out, "Vary", vary);
		}
		@@ -1649,7 +1666,7 @@ dav_error dav_ensure_resource_writable(request_rec r,
		* Note that auto-versioning can only be applied to a version selector,
		* so no separate working resource will be created.
		*/
		if ((err = (*vsn_hooks->checkout)(parent, NULL))
		if ((err = (*vsn_hooks->checkout)(parent, 0, 0, 0, NULL, NULL))
		!= NULL)
		{
		body = apr_psprintf(r->pool,
		@@ -1685,7 +1702,7 @@ dav_error dav_ensure_resource_writable(request_rec r,
		if (!parent_only && !resource->working) {
		/* Auto-versioning can only be applied to version selectors, so
		* no separate working resource will be created. */
		if ((err = (*vsn_hooks->checkout)(resource, NULL))
		if ((err = (*vsn_hooks->checkout)(resource, 0, 0, 0, NULL, NULL))
		!= NULL)
		{
		body = apr_psprintf(r->pool,