Failed to save the file to the "xx" directory.

Failed to save the file to the "ll" directory.

Failed to save the file to the "mm" directory.

Failed to save the file to the "wp" directory.

403WebShell
403Webshell
Server IP : 66.29.132.124  /  Your IP : 18.119.117.77
Web Server : LiteSpeed
System : Linux business141.web-hosting.com 4.18.0-553.lve.el8.x86_64 #1 SMP Mon May 27 15:27:34 UTC 2024 x86_64
User : wavevlvu ( 1524)
PHP Version : 7.4.33
Disable Function : NONE
MySQL : OFF  |  cURL : ON  |  WGET : ON  |  Perl : ON  |  Python : ON  |  Sudo : OFF  |  Pkexec : OFF
Directory :  /usr/include/apache2/

Upload File :
current_dir [ Writeable ] document_root [ Writeable ]

 

Command :


[ Back ]     

Current File : /usr/include/apache2/mod_dav.h
/* Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/**
 * @file  mod_dav.h
 * @brief DAV extension module for Apache 2.0.*
 *
 * @defgroup MOD_DAV mod_dav
 * @ingroup APACHE_MODS
 * @{
 */

#ifndef _MOD_DAV_H_
#define _MOD_DAV_H_

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

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

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

#ifdef __cplusplus
extern "C" {
#endif


#define DAV_VERSION             AP_SERVER_BASEREVISION

#define DAV_XML_HEADER          "<?xml version=\"1.0\" encoding=\"utf-8\"?>"
#define DAV_XML_CONTENT_TYPE    "text/xml; charset=\"utf-8\""

#define DAV_READ_BLOCKSIZE      2048    /* used for reading input blocks */

#define DAV_RESPONSE_BODY_1	"<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01//EN\" \"http://www.w3.org/TR/html4/strict.dtd\">\n<html>\n<head>\n<title>"
#define DAV_RESPONSE_BODY_2     "</title>\n</head><body>\n<h1>"
#define DAV_RESPONSE_BODY_3     "</h1>\n<p>"
#define DAV_RESPONSE_BODY_4     "</p>\n"
#define DAV_RESPONSE_BODY_5     "</body></html>\n"

#define DAV_DO_COPY             0
#define DAV_DO_MOVE             1


#if 1
#define DAV_DEBUG        1
#define DEBUG_CR         "\n"
#define DBG0(f)          ap_log_error(APLOG_MARK, \
                                APLOG_ERR, 0, NULL, (f))
#define DBG1(f,a1)       ap_log_error(APLOG_MARK, \
                                APLOG_ERR, 0, NULL, f, a1)
#define DBG2(f,a1,a2)    ap_log_error(APLOG_MARK, \
                                APLOG_ERR, 0, NULL, f, a1, a2)
#define DBG3(f,a1,a2,a3) ap_log_error(APLOG_MARK, \
                                APLOG_ERR, 0, NULL, f, a1, a2, a3)
#else
#undef DAV_DEBUG
#define DEBUG_CR        ""
#endif

#define DAV_INFINITY    INT_MAX    /* for the Depth: header */

/* Create a set of DAV_DECLARE(type), DAV_DECLARE_NONSTD(type) and
 * DAV_DECLARE_DATA with appropriate export and import tags for the platform
 */
#if !defined(WIN32)
#define DAV_DECLARE(type)            type
#define DAV_DECLARE_NONSTD(type)     type
#define DAV_DECLARE_DATA
#elif defined(DAV_DECLARE_STATIC)
#define DAV_DECLARE(type)            type __stdcall
#define DAV_DECLARE_NONSTD(type)     type
#define DAV_DECLARE_DATA
#elif defined(DAV_DECLARE_EXPORT)
#define DAV_DECLARE(type)            __declspec(dllexport) type __stdcall
#define DAV_DECLARE_NONSTD(type)     __declspec(dllexport) type
#define DAV_DECLARE_DATA             __declspec(dllexport)
#else
#define DAV_DECLARE(type)            __declspec(dllimport) type __stdcall
#define DAV_DECLARE_NONSTD(type)     __declspec(dllimport) type
#define DAV_DECLARE_DATA             __declspec(dllimport)
#endif

/* --------------------------------------------------------------------
**
** ERROR MANAGEMENT
*/

/*
** dav_error structure.
**
** In most cases, mod_dav uses a pointer to a dav_error structure. If the
** pointer is NULL, then no error has occurred.
**
** In certain cases, a dav_error structure is directly used. In these cases,
** a status value of 0 means that an error has not occurred.
**
** Note: this implies that status != 0 whenever an error occurs.
**
** The desc field is optional (it may be NULL). When NULL, it typically
** implies that Apache has a proper description for the specified status.
*/
typedef struct dav_error {
    int status;                 /* suggested HTTP status (0 for no error) */
    int error_id;               /* DAV-specific error ID */
    const char *desc;           /* DAV:responsedescription and error log */

    apr_status_t aprerr;        /* APR error if any, or 0/APR_SUCCESS */

    const char *namespace;      /* [optional] namespace of error */
    const char *tagname;        /* name of error-tag */

    struct dav_error *prev;     /* previous error (in stack) */

    const char *childtags;      /* error-tag may have children */

} dav_error;

/*
** Create a new error structure. save_errno will be filled with the current
** errno value.
*/
DAV_DECLARE(dav_error*) dav_new_error(apr_pool_t *p, int status,
                                      int error_id, apr_status_t aprerr,
                                      const char *desc);


/*
** Create a new error structure with tagname and (optional) namespace;
** namespace may be NULL, which means "DAV:".
*/
DAV_DECLARE(dav_error*) dav_new_error_tag(apr_pool_t *p, int status,
                                          int error_id, apr_status_t aprerr,
                                          const char *desc,
                                          const char *namespace,
                                          const char *tagname);


/*
** Push a new error description onto the stack of errors.
**
** This function is used to provide an additional description to an existing
** error.
**
** <status> should contain the caller's view of what the current status is,
** given the underlying error. If it doesn't have a better idea, then the
** caller should pass prev->status.
**
** <error_id> can specify a new error_id since the topmost description has
** changed.
*/
DAV_DECLARE(dav_error*) dav_push_error(apr_pool_t *p, int status, int error_id,
                                       const char *desc, dav_error *prev);


/*
** Join two errors together.
**
** This function is used to add a new error stack onto an existing error so
** that subsequent errors can be reported after the first error.  It returns
** the correct error stack to use so that the caller can blindly call it
** without checking that both dest and src are not NULL.
** 
** <dest> is the error stack that the error will be added to.
**
** <src> is the error stack that will be appended.
*/
DAV_DECLARE(dav_error*) dav_join_error(dav_error* dest, dav_error* src);

typedef struct dav_response dav_response;

/*
** dav_handle_err()
**
** Handle the standard error processing. <err> must be non-NULL.
**
** <response> is set by the following:
**   - dav_validate_request()
**   - dav_add_lock()
**   - repos_hooks->remove_resource
**   - repos_hooks->move_resource
**   - repos_hooks->copy_resource
**   - vsn_hooks->update
*/
DAV_DECLARE(int) dav_handle_err(request_rec *r, dav_error *err,
                                dav_response *response);

/* error ID values... */

/* IF: header errors */
#define DAV_ERR_IF_PARSE                100    /* general parsing error */
#define DAV_ERR_IF_MULTIPLE_NOT         101    /* multiple "Not" found */
#define DAV_ERR_IF_UNK_CHAR             102    /* unknown char in header */
#define DAV_ERR_IF_ABSENT               103    /* no locktokens given */
#define DAV_ERR_IF_TAGGED               104    /* in parsing tagged-list */
#define DAV_ERR_IF_UNCLOSED_PAREN       105    /* in no-tagged-list */

/* Prop DB errors */
#define DAV_ERR_PROP_BAD_MAJOR          200    /* major version was wrong */
#define DAV_ERR_PROP_READONLY           201    /* prop is read-only */
#define DAV_ERR_PROP_NO_DATABASE        202    /* writable db not avail */
#define DAV_ERR_PROP_NOT_FOUND          203    /* prop not found */
#define DAV_ERR_PROP_BAD_LOCKDB         204    /* could not open lockdb */
#define DAV_ERR_PROP_OPENING            205    /* problem opening propdb */
#define DAV_ERR_PROP_EXEC               206    /* problem exec'ing patch */

/* Predefined DB errors */
/* ### any to define?? */

/* Predefined locking system errors */
#define DAV_ERR_LOCK_OPENDB             400    /* could not open lockdb */
#define DAV_ERR_LOCK_NO_DB              401    /* no database defined */
#define DAV_ERR_LOCK_CORRUPT_DB         402    /* DB is corrupt */
#define DAV_ERR_LOCK_UNK_STATE_TOKEN    403    /* unknown State-token */
#define DAV_ERR_LOCK_PARSE_TOKEN        404    /* bad opaquelocktoken */
#define DAV_ERR_LOCK_SAVE_LOCK          405    /* err saving locks */

/*
** Some comments on Error ID values:
**
** The numbers do not necessarily need to be unique. Uniqueness simply means
** that two errors that have not been predefined above can be distinguished
** from each other. At the moment, mod_dav does not use this distinguishing
** feature, but it could be used in the future to collapse <response> elements
** into groups based on the error ID (and associated responsedescription).
**
** If a compute_desc is provided, then the error ID should be unique within
** the context of the compute_desc function (so the function can figure out
** what to filled into the desc).
**
** Basically, subsystems can ignore defining new error ID values if they want
** to. The subsystems *do* need to return the predefined errors when
** appropriate, so that mod_dav can figure out what to do. Subsystems can
** simply leave the error ID field unfilled (zero) if there isn't an error
** that must be placed there.
*/


/* --------------------------------------------------------------------
**
** HOOK STRUCTURES
**
** These are here for forward-declaration purposes. For more info, see
** the section title "HOOK HANDLING" for more information, plus each
** structure definition.
*/

/* forward-declare this structure */
typedef struct dav_hooks_propdb dav_hooks_propdb;
typedef struct dav_hooks_locks dav_hooks_locks;
typedef struct dav_hooks_vsn dav_hooks_vsn;
typedef struct dav_hooks_repository dav_hooks_repository;
typedef struct dav_hooks_liveprop dav_hooks_liveprop;
typedef struct dav_hooks_binding dav_hooks_binding;
typedef struct dav_hooks_search dav_hooks_search;

/* ### deprecated name */
typedef dav_hooks_propdb dav_hooks_db;


/* --------------------------------------------------------------------
**
** RESOURCE HANDLING
*/

/*
** Resource Types:
** The base protocol defines only file and collection resources.
** The versioning protocol defines several additional resource types
** to represent artifacts of a version control system.
**
** This enumeration identifies the type of URL used to identify the
** resource. Since the same resource may have more than one type of
** URL which can identify it, dav_resource_type cannot be used
** alone to determine the type of the resource; attributes of the
** dav_resource object must also be consulted.
*/
typedef enum {
    DAV_RESOURCE_TYPE_UNKNOWN,

    DAV_RESOURCE_TYPE_REGULAR,          /* file or collection; could be
                                         * unversioned, or version selector,
                                         * or baseline selector */

    DAV_RESOURCE_TYPE_VERSION,          /* version or baseline URL */

    DAV_RESOURCE_TYPE_HISTORY,          /* version or baseline history URL */

    DAV_RESOURCE_TYPE_WORKING,          /* working resource URL */

    DAV_RESOURCE_TYPE_WORKSPACE,        /* workspace URL */

    DAV_RESOURCE_TYPE_ACTIVITY,         /* activity URL */

    DAV_RESOURCE_TYPE_PRIVATE           /* repository-private type */

} dav_resource_type;

/*
** Opaque, repository-specific information for a resource.
*/
typedef struct dav_resource_private dav_resource_private;

/*
** Resource descriptor, generated by a repository provider.
**
** Note: the lock-null state is not explicitly represented here,
** since it may be expensive to compute. Use dav_get_resource_state()
** to determine whether a non-existent resource is a lock-null resource.
**
** A quick explanation of how the flags can apply to different resources:
**
** unversioned file or collection:
**     type       = DAV_RESOURCE_TYPE_REGULAR
**     exists     = ? (1 if exists)
**     collection = ? (1 if collection)
**     versioned  = 0
**     baselined  = 0
**     working    = 0
**
** version-controlled resource or configuration:
**     type       = DAV_RESOURCE_TYPE_REGULAR
**     exists     = 1
**     collection = ? (1 if collection)
**     versioned  = 1
**     baselined  = ? (1 if configuration)
**     working    = ? (1 if checked out)
**
** version/baseline history:
**     type       = DAV_RESOURCE_TYPE_HISTORY
**     exists     = 1
**     collection = 0
**     versioned  = 0
**     baselined  = 0
**     working    = 0
**
** version/baseline:
**     type       = DAV_RESOURCE_TYPE_VERSION
**     exists     = 1
**     collection = ? (1 if collection)
**     versioned  = 1
**     baselined  = ? (1 if baseline)
**     working    = 0
**
** working resource:
**     type       = DAV_RESOURCE_TYPE_WORKING
**     exists     = 1
**     collection = ? (1 if collection)
**     versioned  = 1
**     baselined  = 0
**     working    = 1
**
** workspace:
**     type       = DAV_RESOURCE_TYPE_WORKSPACE
**     exists     = ? (1 if exists)
**     collection = 1
**     versioned  = ? (1 if version-controlled)
**     baselined  = ? (1 if baseline-controlled)
**     working    = ? (1 if checked out)
**
** activity:
**     type       = DAV_RESOURCE_TYPE_ACTIVITY
**     exists     = ? (1 if exists)
**     collection = 0
**     versioned  = 0
**     baselined  = 0
**     working    = 0
*/
typedef struct dav_resource {
    dav_resource_type type;

    int exists;         /* 0 => null resource */

    int collection;     /* 0 => file; can be 1 for
                         * REGULAR, VERSION, and WORKING resources,
                         * and is always 1 for WORKSPACE */

    int versioned;      /* 0 => unversioned; can be 1 for
                         * REGULAR and WORKSPACE resources,
                         * and is always 1 for VERSION and WORKING */

    int baselined;      /* 0 => not baselined; can be 1 for
                         * REGULAR, VERSION, and WORKSPACE resources;
                         * versioned == 1 when baselined == 1 */

    int working;        /* 0 => not checked out; can be 1 for
                         * REGULAR and WORKSPACE resources,
                         * and is always 1 for WORKING */

    const char *uri;    /* the URI for this resource;
                         * currently has an ABI flaw where sometimes it is
                         * assumed to be encoded and sometimes not */

    dav_resource_private *info;         /* the provider's private info */

    const dav_hooks_repository *hooks;  /* hooks used for this resource */

    /* When allocating items related specifically to this resource, the
       following pool should be used. Its lifetime will be at least as
       long as the dav_resource structure. */
    apr_pool_t *pool;

} dav_resource;

/*
** Lock token type. Lock providers define the details of a lock token.
** However, all providers are expected to at least be able to parse
** the "opaquelocktoken" scheme, which is represented by a uuid_t.
*/
typedef struct dav_locktoken dav_locktoken;

DAV_DECLARE(dav_error *) dav_get_resource(request_rec *r, int label_allowed,
                                          int use_checked_in, dav_resource **res_p);


/* --------------------------------------------------------------------
**
** BUFFER HANDLING
**
** These buffers are used as a lightweight buffer reuse mechanism. Apache
** provides sub-pool creation and destruction to much the same effect, but
** the sub-pools are a bit more general and heavyweight than these buffers.
*/

/* buffer for reuse; can grow to accommodate needed size */
typedef struct
{
    apr_size_t alloc_len;       /* how much has been allocated */
    apr_size_t cur_len;         /* how much is currently being used */
    char *buf;                  /* buffer contents */
} dav_buffer;
#define DAV_BUFFER_MINSIZE      256    /* minimum size for buffer */
#define DAV_BUFFER_PAD          64     /* amount of pad when growing */

/* set the cur_len to the given size and ensure space is available */
DAV_DECLARE(void) dav_set_bufsize(apr_pool_t *p, dav_buffer *pbuf,
                                  apr_size_t size);

/* initialize a buffer and copy the specified (null-term'd) string into it */
DAV_DECLARE(void) dav_buffer_init(apr_pool_t *p, dav_buffer *pbuf,
                                  const char *str);

/* check that the buffer can accommodate <extra_needed> more bytes */
DAV_DECLARE(void) dav_check_bufsize(apr_pool_t *p, dav_buffer *pbuf,
                                    apr_size_t extra_needed);

/* append a string to the end of the buffer, adjust length */
DAV_DECLARE(void) dav_buffer_append(apr_pool_t *p, dav_buffer *pbuf,
                                    const char *str);

/* place a string on the end of the buffer, do NOT adjust length */
DAV_DECLARE(void) dav_buffer_place(apr_pool_t *p, dav_buffer *pbuf,
                                   const char *str);

/* place some memory on the end of a buffer; do NOT adjust length */
DAV_DECLARE(void) dav_buffer_place_mem(apr_pool_t *p, dav_buffer *pbuf,
                                       const void *mem, apr_size_t amt,
                                       apr_size_t pad);


/* --------------------------------------------------------------------
**
** HANDY UTILITIES
*/

/* contains results from one of the getprop functions */
typedef struct
{
    apr_text * propstats;       /* <propstat> element text */
    apr_text * xmlns;           /* namespace decls for <response> elem */
} dav_get_props_result;

/* holds the contents of a <response> element */
struct dav_response
{
    const char *href;           /* always */
    const char *desc;           /* optional description at <response> level */

    /* use status if propresult.propstats is NULL. */
    dav_get_props_result propresult;

    int status;

    struct dav_response *next;
};

typedef struct
{
    request_rec *rnew;          /* new subrequest */
    dav_error err;              /* potential error response */
} dav_lookup_result;


DAV_DECLARE(dav_lookup_result) dav_lookup_uri(const char *uri, request_rec *r,
                                              int must_be_absolute);

/* defines type of property info a provider is to return */
typedef enum {
    DAV_PROP_INSERT_NOTDEF,     /* property is defined by this provider,
                                   but nothing was inserted because the
                                   (live) property is not defined for this
                                   resource (it may be present as a dead
                                   property). */
    DAV_PROP_INSERT_NOTSUPP,    /* property is recognized by this provider,
                                   but it is not supported, and cannot be
                                   treated as a dead property */
    DAV_PROP_INSERT_NAME,       /* a property name (empty elem) was
                                   inserted into the text block */
    DAV_PROP_INSERT_VALUE,      /* a property name/value pair was inserted
                                   into the text block */
    DAV_PROP_INSERT_SUPPORTED   /* a supported live property was added to
                                   the text block as a
                                   <DAV:supported-live-property> element */
} dav_prop_insert;

/* ### this stuff is private to dav/fs/repos.c; move it... */
/* format a time string (buf must be at least DAV_TIMEBUF_SIZE chars) */
#define DAV_STYLE_ISO8601       1
#define DAV_STYLE_RFC822        2
#define DAV_TIMEBUF_SIZE        30

/* Write a complete RESPONSE object out as a <DAV:response> xml
 * element.  Data is sent into brigade BB, which is auto-flushed into
 * the output filter stack for request R.  Use POOL for any temporary
 * allocations.
 *
 * [Presumably the <multistatus> tag has already been written;  this
 * routine is shared by dav_send_multistatus and dav_stream_response.]
 */
DAV_DECLARE(void) dav_send_one_response(dav_response *response,
                                        apr_bucket_brigade *bb,
                                        request_rec *r,
                                        apr_pool_t *pool);

/* Factorized helper function: prep request_rec R for a multistatus
 * response and write <multistatus> tag into BB, destined for
 * R->output_filters.  Use xml NAMESPACES in initial tag, if
 * non-NULL.
 */
DAV_DECLARE(void) dav_begin_multistatus(apr_bucket_brigade *bb,
                                        request_rec *r, int status,
                                        apr_array_header_t *namespaces);

/* Finish a multistatus response started by dav_begin_multistatus: */
DAV_DECLARE(apr_status_t) dav_finish_multistatus(request_rec *r,
                                                 apr_bucket_brigade *bb);

/* Send a multistatus response */
DAV_DECLARE(void) dav_send_multistatus(request_rec *r, int status,
                                       dav_response *first,
                                       apr_array_header_t *namespaces);

DAV_DECLARE(apr_text *) dav_failed_proppatch(apr_pool_t *p,
                                             apr_array_header_t *prop_ctx);
DAV_DECLARE(apr_text *) dav_success_proppatch(apr_pool_t *p,
                                              apr_array_header_t *prop_ctx);

DAV_DECLARE(int) dav_get_depth(request_rec *r, int def_depth);

DAV_DECLARE(int) dav_validate_root(const apr_xml_doc *doc,
                                   const char *tagname);
DAV_DECLARE(int) dav_validate_root_ns(const apr_xml_doc *doc,
                                      int ns, const char *tagname);
DAV_DECLARE(apr_xml_elem *) dav_find_child(const apr_xml_elem *elem,
                                           const char *tagname);
DAV_DECLARE(apr_xml_elem *) dav_find_child_ns(const apr_xml_elem *elem,
                                              int ns, const char *tagname);
DAV_DECLARE(apr_xml_elem *) dav_find_next_ns(const apr_xml_elem *elem,
                                             int ns, const char *tagname);

/* find and return the attribute with a name in the given namespace */
DAV_DECLARE(apr_xml_attr *) dav_find_attr_ns(const apr_xml_elem *elem,
                                             int ns, const char *attrname);

/* find and return the attribute with a given DAV: tagname */
DAV_DECLARE(apr_xml_attr *) dav_find_attr(const apr_xml_elem *elem,
                                          const char *attrname);

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

/*
** XML namespace handling
**
** This structure tracks namespace declarations (xmlns:prefix="URI").
** It maintains a one-to-many relationship of URIs-to-prefixes. In other
** words, one URI may be defined by many prefixes, but any specific
** prefix will specify only one URI.
**
** Prefixes using the "g###" pattern can be generated automatically if
** the caller does not have specific prefix requirements.
*/
typedef struct {
    apr_pool_t *pool;
    apr_hash_t *uri_prefix;     /* map URIs to an available prefix */
    apr_hash_t *prefix_uri;     /* map all prefixes to their URIs */
    int count;                  /* counter for "g###" prefixes */
} dav_xmlns_info;

/* create an empty dav_xmlns_info structure */
DAV_DECLARE(dav_xmlns_info *) dav_xmlns_create(apr_pool_t *pool);

/* add a specific prefix/URI pair. the prefix/uri should have a lifetime
   at least that of xmlns->pool */
DAV_DECLARE(void) dav_xmlns_add(dav_xmlns_info *xi,
                                const char *prefix, const char *uri);

/* add a URI (if not present); any prefix is acceptable and is returned.
   the uri should have a lifetime at least that xmlns->pool */
DAV_DECLARE(const char *) dav_xmlns_add_uri(dav_xmlns_info *xi,
                                            const char *uri);

/* return the URI for a specified prefix (or NULL if the prefix is unknown) */
DAV_DECLARE(const char *) dav_xmlns_get_uri(dav_xmlns_info *xi,
                                            const char *prefix);

/* return an available prefix for a specified URI (or NULL if the URI
   is unknown) */
DAV_DECLARE(const char *) dav_xmlns_get_prefix(dav_xmlns_info *xi,
                                               const char *uri);

/* generate xmlns declarations (appending into the given text) */
DAV_DECLARE(void) dav_xmlns_generate(dav_xmlns_info *xi,
                                     apr_text_header *phdr);

/* --------------------------------------------------------------------
**
** DAV PLUGINS
*/

/* ### docco ... */

/*
** dav_provider
**
** This structure wraps up all of the hooks that a mod_dav provider can
** supply. The provider MUST supply <repos> and <propdb>. The rest are
** optional and should contain NULL if that feature is not supplied.
**
** Note that a provider cannot pick and choose portions from various
** underlying implementations (which was theoretically possible in
** mod_dav 1.0). There are too many dependencies between a dav_resource
** (defined by <repos>) and the other functionality.
**
** Live properties and report extensions are not part of the dav_provider
** structure because they are handled through the APR_HOOK interface (to
** allow for multiple providers). The core always provides some
** properties, and then a given provider will add more properties.
**
** Some providers may need to associate a context with the dav_provider
** structure -- the ctx field is available for storing this context. Just
** leave it NULL if it isn't required.
*/
typedef struct {
    const dav_hooks_repository *repos;
    const dav_hooks_propdb *propdb;
    const dav_hooks_locks *locks;
    const dav_hooks_vsn *vsn;
    const dav_hooks_binding *binding;
    const dav_hooks_search *search;

    void *ctx;
} dav_provider;

/*
** gather_propsets: gather all live property propset-URIs
**
** The hook implementor should push one or more URIs into the specified
** array. These URIs are returned in the DAV: header to let clients know
** what sets of live properties are supported by the installation. mod_dav
** will place open/close angle brackets around each value (much like
** a Coded-URL); quotes and brackets should not be in the value.
**
** Example:    http://apache.org/dav/props/
**
** (of course, use your own domain to ensure a unique value)
*/
APR_DECLARE_EXTERNAL_HOOK(dav, DAV, void, gather_propsets,
                         (apr_array_header_t *uris))

/*
** find_liveprop: find a live property, returning a non-zero, unique,
**                opaque identifier.
**
** If the hook implementor determines the specified URI/name refers to
** one of its properties, then it should fill in HOOKS and return a
** non-zero value. The returned value is the "property ID" and will
** be passed to the various liveprop hook functions.
**
** Return 0 if the property is not defined by the hook implementor.
*/
APR_DECLARE_EXTERNAL_HOOK(dav, DAV, int, find_liveprop,
                         (const dav_resource *resource,
                          const char *ns_uri, const char *name,
                          const dav_hooks_liveprop **hooks))

/*
** insert_all_liveprops: insert all (known) live property names/values.
**
** The hook implementor should append XML text to PHDR, containing liveprop
** names. If INSVALUE is true, then the property values should also be
** inserted into the output XML stream.
**
** The liveprop provider should insert *all* known and *defined* live
** properties on the specified resource. If a particular liveprop is
** not defined for this resource, then it should not be inserted.
*/
APR_DECLARE_EXTERNAL_HOOK(dav, DAV, void, insert_all_liveprops,
                         (request_rec *r, const dav_resource *resource,
                          dav_prop_insert what, apr_text_header *phdr))

/*
** deliver_report: given a parsed report request, process the request
**                 an deliver the resulting report.
**
** The hook implementer should decide whether it should handle the given
** report, and if so, write the response to the output filter. If the
** report is not relevant, return DECLINED.
*/
APR_DECLARE_EXTERNAL_HOOK(dav, DAV, int, deliver_report,
                         (request_rec *r,
                          const dav_resource *resource,
                          const apr_xml_doc *doc,
                          ap_filter_t *output, dav_error **err))

/*
** gather_reports: get all reports.
**
** The hook implementor should push one or more dav_report_elem structures
** containing report names into the specified array. These names are returned
** in the DAV:supported-reports-set property to let clients know
** what reports are supported by the installation.
**
*/
APR_DECLARE_EXTERNAL_HOOK(dav, DAV, void, gather_reports,
                          (request_rec *r, const dav_resource *resource,
                           apr_array_header_t *reports, dav_error **err))

/*
 ** method_precondition: check method preconditions.
 **
 ** If a WebDAV extension needs to set any preconditions on a method, this
 ** hook is where to do it. If the precondition fails, return an error
 ** response with the tagname set to the value of the failed precondition.
 **
 ** If the method requires an XML body, this will be read and provided as
 ** the doc value. If not, doc is NULL. An extension that needs to verify
 ** the non-XML body of a request should register an input filter to do so
 ** within this hook.
 **
 ** Methods like PUT will supply a single src resource, and the dst will
 ** be NULL.
 **
 ** Methods like COPY or MOVE will trigger this hook twice. The first
 ** invocation will supply just the source resource. The second invocation
 ** will supply a source and destination. This allows preconditions on the
 ** source resource to be verified before making an attempt to get the
 ** destination resource.
 **
 ** Methods like PROPFIND and LABEL will trigger this hook initially for
 ** the src resource, and then subsequently for each resource that has
 ** been walked during processing, with the walked resource passed in dst,
 ** and NULL passed in src.
 **
 ** As a rule, the src resource originates from a request that has passed
 ** through httpd's authn/authz hooks, while the dst resource has not.
 */
APR_DECLARE_EXTERNAL_HOOK(dav, DAV, int, method_precondition,
                          (request_rec *r,
                           dav_resource *src, const dav_resource *dst,
                           const apr_xml_doc *doc, dav_error **err))


DAV_DECLARE(const dav_hooks_locks *) dav_get_lock_hooks(request_rec *r);
DAV_DECLARE(const dav_hooks_propdb *) dav_get_propdb_hooks(request_rec *r);
DAV_DECLARE(const dav_hooks_vsn *) dav_get_vsn_hooks(request_rec *r);
DAV_DECLARE(const dav_hooks_binding *) dav_get_binding_hooks(request_rec *r);
DAV_DECLARE(const dav_hooks_search *) dav_get_search_hooks(request_rec *r);

DAV_DECLARE(void) dav_register_provider(apr_pool_t *p, const char *name,
                                        const dav_provider *hooks);
DAV_DECLARE(const dav_provider *) dav_lookup_provider(const char *name);
DAV_DECLARE(const char *) dav_get_provider_name(request_rec *r);
DAV_DECLARE(const dav_provider *) dav_get_provider(request_rec *r);


/* ### deprecated */
#define DAV_GET_HOOKS_PROPDB(r)         dav_get_propdb_hooks(r)
#define DAV_GET_HOOKS_LOCKS(r)          dav_get_lock_hooks(r)
#define DAV_GET_HOOKS_VSN(r)            dav_get_vsn_hooks(r)
#define DAV_GET_HOOKS_BINDING(r)        dav_get_binding_hooks(r)
#define DAV_GET_HOOKS_SEARCH(r)         dav_get_search_hooks(r)


/* --------------------------------------------------------------------
**
** IF HEADER PROCESSING
**
** Here is the definition of the If: header from RFC 2518, S9.4:
**
**    If = "If" ":" (1*No-tag-list | 1*Tagged-list)
**    No-tag-list = List
**    Tagged-list = Resource 1*List
**    Resource = Coded-URL
**    List = "(" 1*(["Not"](State-token | "[" entity-tag "]")) ")"
**    State-token = Coded-URL
**    Coded-URL = "<" absoluteURI ">"        ; absoluteURI from RFC 2616
**
** List corresponds to dav_if_state_list. No-tag-list corresponds to
** dav_if_header with uri==NULL. Tagged-list corresponds to a sequence of
** dav_if_header structures with (duplicate) uri==Resource -- one
** dav_if_header per state_list. A second Tagged-list will start a new
** sequence of dav_if_header structures with the new URI.
**
** A summary of the semantics, mapped into our structures:
**    - Chained dav_if_headers: OR
**    - Chained dav_if_state_lists: AND
**    - NULL uri matches all resources
*/

typedef enum
{
    dav_if_etag,
    dav_if_opaquelock,
    dav_if_unknown /* the "unknown" state type; always matches false. */
} dav_if_state_type;

typedef struct dav_if_state_list
{
    dav_if_state_type type;

    int condition;
#define DAV_IF_COND_NORMAL      0
#define DAV_IF_COND_NOT         1    /* "Not" was applied */

    const char *etag;
    dav_locktoken *locktoken;

    struct dav_if_state_list *next;
} dav_if_state_list;

typedef struct dav_if_header
{
    const char *uri;
    apr_size_t uri_len;
    struct dav_if_state_list *state;
    struct dav_if_header *next;

    int dummy_header;   /* used internally by the lock/etag validation */
} dav_if_header;

typedef struct dav_locktoken_list
{
    dav_locktoken *locktoken;
    struct dav_locktoken_list *next;
} dav_locktoken_list;

DAV_DECLARE(dav_error *) dav_get_locktoken_list(request_rec *r,
                                                dav_locktoken_list **ltl);


/* --------------------------------------------------------------------
**
** LIVE PROPERTY HANDLING
*/

/* opaque type for PROPPATCH rollback information */
typedef struct dav_liveprop_rollback dav_liveprop_rollback;

struct dav_hooks_liveprop
{
    /*
    ** Insert property information into a text block. The property to
    ** insert is identified by the propid value. The information to insert
    ** is identified by the "what" argument, as follows:
    **   DAV_PROP_INSERT_NAME
    **      property name, as an empty XML element
    **   DAV_PROP_INSERT_VALUE
    **      property name/value, as an XML element
    **   DAV_PROP_INSERT_SUPPORTED
    **      if the property is defined on the resource, then
    **      a DAV:supported-live-property element, as defined
    **      by the DeltaV extensions to RFC2518.
    **
    ** Providers should return DAV_PROP_INSERT_NOTDEF if the property is
    ** known and not defined for this resource, so should be handled as a
    ** dead property. If a provider recognizes, but does not support, a
    ** property, and does not want it handled as a dead property, it should
    ** return DAV_PROP_INSERT_NOTSUPP.
    **
    ** Some DAV extensions, like CalDAV, specify both document elements
    ** and property elements that need to be taken into account when
    ** generating a property. The document element and property element
    ** are made available in the dav_liveprop_elem structure under the
    ** resource, accessible as follows:
    **
    ** dav_get_liveprop_element(resource);
    **
    ** Returns one of DAV_PROP_INSERT_* based on what happened.
    **
    ** ### we may need more context... ie. the lock database
    */
    dav_prop_insert (*insert_prop)(const dav_resource *resource,
                                   int propid, dav_prop_insert what,
                                   apr_text_header *phdr);

    /*
    ** Determine whether a given property is writable.
    **
    ** ### we may want a different semantic. i.e. maybe it should be
    ** ### "can we write <value> into this property?"
    **
    ** Returns 1 if the live property can be written, 0 if read-only.
    */
    int (*is_writable)(const dav_resource *resource, int propid);

    /*
    ** This member defines the set of namespace URIs that the provider
    ** uses for its properties. When insert_all is called, it will be
    ** passed a list of integers that map from indices into this list
    ** to namespace IDs for output generation.
    **
    ** The last entry in this list should be a NULL value (sentinel).
    */
    const char * const * namespace_uris;

    /*
    ** ### this is not the final design. we want an open-ended way for
    ** ### liveprop providers to attach *new* properties. To this end,
    ** ### we'll have a "give me a list of the props you define", a way
    ** ### to check for a prop's existence, a way to validate a set/remove
    ** ### of a prop, and a way to execute/commit/rollback that change.
    */

    /*
    ** Validate that the live property can be assigned a value, and that
    ** the provided value is valid.
    **
    ** elem will point to the XML element that names the property. For
    ** example:
    **     <lp1:executable>T</lp1:executable>
    **
    ** The provider can access the cdata fields and the child elements
    ** to extract the relevant pieces.
    **
    ** operation is one of DAV_PROP_OP_SET or _DELETE.
    **
    ** The provider may return a value in *context which will be passed
    ** to each of the exec/commit/rollback functions. For example, this
    ** may contain an internal value which has been processed from the
    ** input element.
    **
    ** The provider must set defer_to_dead to true (non-zero) or false.
    ** If true, then the set/remove is deferred to the dead property
    ** database. Note: it will be set to zero on entry.
    */
    dav_error * (*patch_validate)(const dav_resource *resource,
                                  const apr_xml_elem *elem,
                                  int operation,
                                  void **context,
                                  int *defer_to_dead);

    /* ### doc... */
    dav_error * (*patch_exec)(const dav_resource *resource,
                              const apr_xml_elem *elem,
                              int operation,
                              void *context,
                              dav_liveprop_rollback **rollback_ctx);

    /* ### doc... */
    void (*patch_commit)(const dav_resource *resource,
                         int operation,
                         void *context,
                         dav_liveprop_rollback *rollback_ctx);

    /* ### doc... */
    dav_error * (*patch_rollback)(const dav_resource *resource,
                                  int operation,
                                  void *context,
                                  dav_liveprop_rollback *rollback_ctx);

    /*
    ** If a provider needs a context to associate with this hooks structure,
    ** then this field may be used. In most cases, it will just be NULL.
    */
    void *ctx;
};

/*
** dav_liveprop_spec: specify a live property
**
** This structure is used as a standard way to determine if a particular
** property is a live property. Its use is not part of the mandated liveprop
** interface, but can be used by liveprop providers in conjunction with the
** utility routines below.
**
** spec->name == NULL is the defined end-sentinel for a list of specs.
*/
typedef struct {
    int ns;             /* provider-local namespace index */
    const char *name;   /* name of the property */

    int propid;         /* provider-local property ID */

    int is_writable;    /* is the property writable? */

} dav_liveprop_spec;

/*
** dav_liveprop_group: specify a group of liveprops
**
** This structure specifies a group of live properties, their namespaces,
** and how to handle them.
*/
typedef struct {
    const dav_liveprop_spec *specs;
    const char * const *namespace_uris;
    const dav_hooks_liveprop *hooks;

} dav_liveprop_group;

/* ### docco */
DAV_DECLARE(int) dav_do_find_liveprop(const char *ns_uri, const char *name,
                                      const dav_liveprop_group *group,
                                      const dav_hooks_liveprop **hooks);

/* ### docco */
DAV_DECLARE(long) dav_get_liveprop_info(int propid,
                                        const dav_liveprop_group *group,
                                        const dav_liveprop_spec **info);

/* ### docco */
DAV_DECLARE(void) dav_register_liveprop_group(apr_pool_t *pool,
                                              const dav_liveprop_group *group);

/* ### docco */
DAV_DECLARE(long) dav_get_liveprop_ns_index(const char *uri);

/* ### docco */
DAV_DECLARE(long) dav_get_liveprop_ns_count(void);

/* ### docco */
DAV_DECLARE(void) dav_add_all_liveprop_xmlns(apr_pool_t *p,
                                             apr_text_header *phdr);

typedef struct {
    const apr_xml_doc *doc;
    const apr_xml_elem *elem;
} dav_liveprop_elem;

/*
 ** When calling insert_prop(), the associated request element and
 ** document is accessible using the following call.
 */
DAV_DECLARE(dav_liveprop_elem *) dav_get_liveprop_element(const dav_resource
                                                          *resource);

/*
** The following three functions are part of mod_dav's internal handling
** for the core WebDAV properties. They are not part of mod_dav's API.
*/
DAV_DECLARE_NONSTD(int) dav_core_find_liveprop(
    const dav_resource *resource,
    const char *ns_uri,
    const char *name,
    const dav_hooks_liveprop **hooks);
DAV_DECLARE_NONSTD(void) dav_core_insert_all_liveprops(
    request_rec *r,
    const dav_resource *resource,
    dav_prop_insert what,
    apr_text_header *phdr);
DAV_DECLARE_NONSTD(void) dav_core_register_uris(apr_pool_t *p);


/*
** Standard WebDAV Property Identifiers
**
** A live property provider does not need to use these; they are simply
** provided for convenience.
**
** Property identifiers need to be unique within a given provider, but not
** *across* providers (note: this uniqueness constraint was different in
** older versions of mod_dav).
**
** The identifiers start at 20000 to make it easier for providers to avoid
** conflicts with the standard properties. The properties are arranged
** alphabetically, and may be reordered from time to time (as properties
** are introduced).
**
** NOTE: there is no problem with reordering (e.g. binary compat) since the
** identifiers are only used within a given provider, which would pick up
** the entire set of changes upon a recompile.
*/
enum {
    DAV_PROPID_BEGIN = 20000,

    /* Standard WebDAV properties (RFC 2518) */
    DAV_PROPID_creationdate,
    DAV_PROPID_displayname,
    DAV_PROPID_getcontentlanguage,
    DAV_PROPID_getcontentlength,
    DAV_PROPID_getcontenttype,
    DAV_PROPID_getetag,
    DAV_PROPID_getlastmodified,
    DAV_PROPID_lockdiscovery,
    DAV_PROPID_resourcetype,
    DAV_PROPID_source,
    DAV_PROPID_supportedlock,

    /* DeltaV properties (from the I-D (#14)) */
    DAV_PROPID_activity_checkout_set,
    DAV_PROPID_activity_set,
    DAV_PROPID_activity_version_set,
    DAV_PROPID_auto_merge_set,
    DAV_PROPID_auto_version,
    DAV_PROPID_baseline_collection,
    DAV_PROPID_baseline_controlled_collection,
    DAV_PROPID_baseline_controlled_collection_set,
    DAV_PROPID_checked_in,
    DAV_PROPID_checked_out,
    DAV_PROPID_checkin_fork,
    DAV_PROPID_checkout_fork,
    DAV_PROPID_checkout_set,
    DAV_PROPID_comment,
    DAV_PROPID_creator_displayname,
    DAV_PROPID_current_activity_set,
    DAV_PROPID_current_workspace_set,
    DAV_PROPID_default_variant,
    DAV_PROPID_eclipsed_set,
    DAV_PROPID_label_name_set,
    DAV_PROPID_merge_set,
    DAV_PROPID_precursor_set,
    DAV_PROPID_predecessor_set,
    DAV_PROPID_root_version,
    DAV_PROPID_subactivity_set,
    DAV_PROPID_subbaseline_set,
    DAV_PROPID_successor_set,
    DAV_PROPID_supported_method_set,
    DAV_PROPID_supported_live_property_set,
    DAV_PROPID_supported_report_set,
    DAV_PROPID_unreserved,
    DAV_PROPID_variant_set,
    DAV_PROPID_version_controlled_binding_set,
    DAV_PROPID_version_controlled_configuration,
    DAV_PROPID_version_history,
    DAV_PROPID_version_name,
    DAV_PROPID_workspace,
    DAV_PROPID_workspace_checkout_set,

    DAV_PROPID_END
};

/*
** Property Identifier Registration
**
** At the moment, mod_dav requires live property providers to ensure that
** each property returned has a unique value. For now, this is done through
** central registration (there are no known providers other than the default,
** so this remains manageable).
**
** WARNING: the TEST ranges should never be "shipped".
*/
#define DAV_PROPID_CORE         10000   /* ..10099. defined by mod_dav */
#define DAV_PROPID_FS           10100   /* ..10299.
                                           mod_dav filesystem provider. */
#define DAV_PROPID_TEST1        10300   /* ..10399 */
#define DAV_PROPID_TEST2        10400   /* ..10499 */
#define DAV_PROPID_TEST3        10500   /* ..10599 */
/* Next: 10600 */


/* --------------------------------------------------------------------
**
** DATABASE FUNCTIONS
*/

typedef struct dav_db dav_db;
typedef struct dav_namespace_map dav_namespace_map;
typedef struct dav_deadprop_rollback dav_deadprop_rollback;

typedef struct {
    const char *ns;     /* "" signals "no namespace" */
    const char *name;
} dav_prop_name;

/* hook functions to enable pluggable databases */
struct dav_hooks_propdb
{
    dav_error * (*open)(apr_pool_t *p, const dav_resource *resource, int ro,
                        dav_db **pdb);
    void (*close)(dav_db *db);

    /*
    ** In bulk, define any namespaces that the values and their name
    ** elements may need.
    **
    ** Note: sometimes mod_dav will defer calling this until output_value
    ** returns found==1. If the output process needs the dav_xmlns_info
    ** filled for its work, then it will need to fill it on demand rather
    ** than depending upon this hook to fill in the structure.
    **
    ** Note: this will *always* be called during an output sequence. Thus,
    ** the provider may rely solely on using this to fill the xmlns info.
    */
    dav_error * (*define_namespaces)(dav_db *db, dav_xmlns_info *xi);

    /*
    ** Output the value from the database (i.e. add an element name and
    ** the value into *phdr). Set *found based on whether the name/value
    ** was found in the propdb.
    **
    ** Note: it is NOT an error for the key/value pair to not exist.
    **
    ** The dav_xmlns_info passed to define_namespaces() is also passed to
    ** each output_value() call so that namespaces can be added on-demand.
    ** It can also be used to look up prefixes or URIs during the output
    ** process.
    */
    dav_error * (*output_value)(dav_db *db, const dav_prop_name *name,
                                dav_xmlns_info *xi,
                                apr_text_header *phdr, int *found);

    /*
    ** Build a mapping from "global" namespaces (stored in apr_xml_*)
    ** into provider-local namespace identifiers.
    **
    ** This mapping should be done once per set of namespaces, and the
    ** resulting mapping should be passed into the store() hook function.
    **
    ** Note: usually, there is just a single document/namespaces for all
    ** elements passed. However, the generality of creating multiple
    ** mappings and passing them to store() is provided here.
    **
    ** Note: this is only in preparation for a series of store() calls.
    ** As a result, the propdb must be open for read/write access when
    ** this function is called.
    */
    dav_error * (*map_namespaces)(dav_db *db,
                                  const apr_array_header_t *namespaces,
                                  dav_namespace_map **mapping);

    /*
    ** Store a property value for a given name. The value->combined field
    ** MUST be set for this call.
    **
    ** ### WARNING: current providers will quote the text within ELEM.
    ** ### this implies you can call this function only once with a given
    ** ### element structure (a second time will quote it again).
    */
    dav_error * (*store)(dav_db *db, const dav_prop_name *name,
                         const apr_xml_elem *elem,
                         dav_namespace_map *mapping);

    /* remove a given property */
    dav_error * (*remove)(dav_db *db, const dav_prop_name *name);

    /* returns 1 if the record specified by "key" exists; 0 otherwise */
    int (*exists)(dav_db *db, const dav_prop_name *name);

    /*
    ** Iterate over the property names in the database.
    **
    ** iter->name.ns == iter->name.name == NULL when there are no more names.
    **
    ** Note: only one iteration may occur over the propdb at a time.
    */
    dav_error * (*first_name)(dav_db *db, dav_prop_name *pname);
    dav_error * (*next_name)(dav_db *db, dav_prop_name *pname);

    /*
    ** Rollback support: get rollback context, and apply it.
    **
    ** struct dav_deadprop_rollback is a provider-private structure; it
    ** should remember the name, and the name's old value (or the fact that
    ** the value was not present, and should be deleted if a rollback occurs).
    */
    dav_error * (*get_rollback)(dav_db *db, const dav_prop_name *name,
                                dav_deadprop_rollback **prollback);
    dav_error * (*apply_rollback)(dav_db *db,
                                  dav_deadprop_rollback *rollback);

    /*
    ** If a provider needs a context to associate with this hooks structure,
    ** then this field may be used. In most cases, it will just be NULL.
    */
    void *ctx;
};


/* --------------------------------------------------------------------
**
** LOCK FUNCTIONS
*/

/* Used to represent a Timeout header of "Infinity" */
#define DAV_TIMEOUT_INFINITE 0

DAV_DECLARE(time_t) dav_get_timeout(request_rec *r);

/*
** Opaque, provider-specific information for a lock database.
*/
typedef struct dav_lockdb_private dav_lockdb_private;

/*
** Opaque, provider-specific information for a lock record.
*/
typedef struct dav_lock_private dav_lock_private;

/*
** Lock database type. Lock providers are urged to implement a "lazy" open, so
** doing an "open" is cheap until something is actually needed from the DB.
*/
typedef struct
{
    const dav_hooks_locks *hooks;   /* the hooks used for this lockdb */
    int ro;                         /* was it opened readonly? */

    dav_lockdb_private *info;

} dav_lockdb;

typedef enum {
    DAV_LOCKSCOPE_UNKNOWN,
    DAV_LOCKSCOPE_EXCLUSIVE,
    DAV_LOCKSCOPE_SHARED
} dav_lock_scope;

typedef enum {
    DAV_LOCKTYPE_UNKNOWN,
    DAV_LOCKTYPE_WRITE
} dav_lock_type;

typedef enum {
    DAV_LOCKREC_DIRECT,             /* lock asserted on this resource */
    DAV_LOCKREC_INDIRECT,           /* lock inherited from a parent */
    DAV_LOCKREC_INDIRECT_PARTIAL    /* most info is not filled in */
} dav_lock_rectype;

/*
** dav_lock: hold information about a lock on a resource.
**
** This structure is used for both direct and indirect locks. A direct lock
** is a lock applied to a specific resource by the client. An indirect lock
** is one that is inherited from a parent resource by virtue of a non-zero
** Depth: header when the lock was applied.
**
** mod_dav records both types of locks in the lock database, managing their
** addition/removal as resources are moved about the namespace.
**
** Note that the lockdb is free to marshal this structure in any form that
** it likes.
**
** For a "partial" lock, the <rectype> and <locktoken> fields must be filled
** in. All other (user) fields should be zeroed. The lock provider will
** usually fill in the <info> field, and the <next> field may be used to
** construct a list of partial locks.
**
** The lock provider MUST use the info field to store a value such that a
** dav_lock structure can locate itself in the underlying lock database.
** This requirement is needed for refreshing: when an indirect dav_lock is
** refreshed, its reference to the direct lock does not specify the direct's
** resource, so the only way to locate the (refreshed, direct) lock in the
** database is to use the info field.
**
** Note that <is_locknull> only refers to the resource where this lock was
** found.
** ### hrm. that says the abstraction is wrong. is_locknull may disappear.
*/
typedef struct dav_lock
{
    dav_lock_rectype rectype;   /* type of lock record */
    int is_locknull;            /* lock establishes a locknull resource */

    /* ### put the resource in here? */

    dav_lock_scope scope;       /* scope of the lock */
    dav_lock_type type;         /* type of lock */
    int depth;                  /* depth of the lock */
    time_t timeout;             /* when the lock will timeout */

    const dav_locktoken *locktoken;  /* the token that was issued */

    const char *owner;          /* (XML) owner of the lock */
    const char *auth_user;      /* auth'd username owning lock */

    dav_lock_private *info;     /* private to the lockdb */

    struct dav_lock *next;      /* for managing a list of locks */
} dav_lock;

/* Property-related public lock functions */
DAV_DECLARE(const char *)dav_lock_get_activelock(request_rec *r,
                                                 dav_lock *locks,
                                                 dav_buffer *pbuf);

/* LockDB-related public lock functions */
DAV_DECLARE(dav_error *) dav_open_lockdb(request_rec *r,
                                         int ro,
                                         dav_lockdb **lockdb);
DAV_DECLARE(void) dav_close_lockdb(dav_lockdb *lockdb);
DAV_DECLARE(dav_error *) dav_lock_parse_lockinfo(request_rec *r,
                                                 const dav_resource *resource,
                                                 dav_lockdb *lockdb,
                                                 const apr_xml_doc *doc,
                                                 dav_lock **lock_request);
DAV_DECLARE(int) dav_unlock(request_rec *r,
                            const dav_resource *resource,
                            const dav_locktoken *locktoken);
DAV_DECLARE(dav_error *) dav_add_lock(request_rec *r,
                                      const dav_resource *resource,
                                      dav_lockdb *lockdb, dav_lock *request,
                                      dav_response **response);
DAV_DECLARE(dav_error *) dav_notify_created(request_rec *r,
                                            dav_lockdb *lockdb,
                                            const dav_resource *resource,
                                            int resource_state,
                                            int depth);

DAV_DECLARE(dav_error*) dav_lock_query(dav_lockdb *lockdb,
                                       const dav_resource *resource,
                                       dav_lock **locks);

DAV_DECLARE(dav_error *) dav_validate_request(request_rec *r,
                                              dav_resource *resource,
                                              int depth,
                                              dav_locktoken *locktoken,
                                              dav_response **response,
                                              int flags,
                                              dav_lockdb *lockdb);
/*
** flags:
**    0x0F -- reserved for <dav_lock_scope> values
**
**    other flags, detailed below
*/
#define DAV_VALIDATE_RESOURCE   0x0010  /* validate just the resource */
#define DAV_VALIDATE_PARENT     0x0020  /* validate resource AND its parent */
#define DAV_VALIDATE_ADD_LD     0x0040  /* add DAV:lockdiscovery into
                                           the 424 DAV:response */
#define DAV_VALIDATE_USE_424    0x0080  /* return 424 status, not 207 */
#define DAV_VALIDATE_IS_PARENT  0x0100  /* for internal use */
#define DAV_VALIDATE_NO_MODIFY  0x0200  /* resource is not being modified
                                           so allow even if lock token
                                           is not provided */

/* Lock-null related public lock functions */
DAV_DECLARE(int) dav_get_resource_state(request_rec *r,
                                        const dav_resource *resource);

/* Lock provider hooks. Locking is optional, so there may be no
 * lock provider for a given repository.
 */
struct dav_hooks_locks
{
    /* Return the supportedlock property for a resource */
    const char * (*get_supportedlock)(
        const dav_resource *resource
    );

    /* Parse a lock token URI, returning a lock token object allocated
     * in the given pool.
     */
    dav_error * (*parse_locktoken)(
        apr_pool_t *p,
        const char *char_token,
        dav_locktoken **locktoken_p
    );

    /* Format a lock token object into a URI string, allocated in
     * the given pool.
     *
     * Always returns non-NULL.
     */
    const char * (*format_locktoken)(
        apr_pool_t *p,
        const dav_locktoken *locktoken
    );

    /* Compare two lock tokens.
     *
     * Result < 0  => lt1 < lt2
     * Result == 0 => lt1 == lt2
     * Result > 0  => lt1 > lt2
     */
    int (*compare_locktoken)(
        const dav_locktoken *lt1,
        const dav_locktoken *lt2
    );

    /* Open the provider's lock database.
     *
     * The provider may or may not use a "real" database for locks
     * (a lock could be an attribute on a resource, for example).
     *
     * The provider may choose to use the value of the DAVLockDB directive
     * (as returned by dav_get_lockdb_path()) to decide where to place
     * any storage it may need.
     *
     * The request storage pool should be associated with the lockdb,
     * so it can be used in subsequent operations.
     *
     * If ro != 0, only readonly operations will be performed.
     * If force == 0, the open can be "lazy"; no subsequent locking operations
     * may occur.
     * If force != 0, locking operations will definitely occur.
     */
    dav_error * (*open_lockdb)(
        request_rec *r,
        int ro,
        int force,
        dav_lockdb **lockdb
    );

    /* Indicates completion of locking operations */
    void (*close_lockdb)(
        dav_lockdb *lockdb
    );

    /* Take a resource out of the lock-null state. */
    dav_error * (*remove_locknull_state)(
        dav_lockdb *lockdb,
        const dav_resource *resource
    );

    /*
    ** Create a (direct) lock structure for the given resource. A locktoken
    ** will be created.
    **
    ** The lock provider may store private information into lock->info.
    */
    dav_error * (*create_lock)(dav_lockdb *lockdb,
                               const dav_resource *resource,
                               dav_lock **lock);

    /*
    ** Get the locks associated with the specified resource.
    **
    ** If resolve_locks is true (non-zero), then any indirect locks are
    ** resolved to their actual, direct lock (i.e. the reference to followed
    ** to the original lock).
    **
    ** The locks, if any, are returned as a linked list in no particular
    ** order. If no locks are present, then *locks will be NULL.
    */
    dav_error * (*get_locks)(dav_lockdb *lockdb,
                             const dav_resource *resource,
                             int calltype,
                             dav_lock **locks);

#define DAV_GETLOCKS_RESOLVED   0    /* resolve indirects to directs */
#define DAV_GETLOCKS_PARTIAL    1    /* leave indirects partially filled */
#define DAV_GETLOCKS_COMPLETE   2    /* fill out indirect locks */

    /*
    ** Find a particular lock on a resource (specified by its locktoken).
    **
    ** *lock will be set to NULL if the lock is not found.
    **
    ** Note that the provider can optimize the unmarshalling -- only one
    ** lock (or none) must be constructed and returned.
    **
    ** If partial_ok is true (non-zero), then an indirect lock can be
    ** partially filled in. Otherwise, another lookup is done and the
    ** lock structure will be filled out as a DAV_LOCKREC_INDIRECT.
    */
    dav_error * (*find_lock)(dav_lockdb *lockdb,
                             const dav_resource *resource,
                             const dav_locktoken *locktoken,
                             int partial_ok,
                             dav_lock **lock);

    /*
    ** Quick test to see if the resource has *any* locks on it.
    **
    ** This is typically used to determine if a non-existent resource
    ** has a lock and is (therefore) a locknull resource.
    **
    ** WARNING: this function may return TRUE even when timed-out locks
    **          exist (i.e. it may not perform timeout checks).
    */
    dav_error * (*has_locks)(dav_lockdb *lockdb,
                             const dav_resource *resource,
                             int *locks_present);

    /*
    ** Append the specified lock(s) to the set of locks on this resource.
    **
    ** If "make_indirect" is true (non-zero), then the specified lock(s)
    ** should be converted to an indirect lock (if it is a direct lock)
    ** before appending. Note that the conversion to an indirect lock does
    ** not alter the passed-in lock -- the change is internal the
    ** append_locks function.
    **
    ** Multiple locks are specified using the lock->next links.
    */
    dav_error * (*append_locks)(dav_lockdb *lockdb,
                                const dav_resource *resource,
                                int make_indirect,
                                const dav_lock *lock);

    /*
    ** Remove any lock that has the specified locktoken.
    **
    ** If locktoken == NULL, then ALL locks are removed.
    */
    dav_error * (*remove_lock)(dav_lockdb *lockdb,
                               const dav_resource *resource,
                               const dav_locktoken *locktoken);

    /*
    ** Refresh all locks, found on the specified resource, which has a
    ** locktoken in the provided list.
    **
    ** If the lock is indirect, then the direct lock is referenced and
    ** refreshed.
    **
    ** Each lock that is updated is returned in the <locks> argument.
    ** Note that the locks will be fully resolved.
    */
    dav_error * (*refresh_locks)(dav_lockdb *lockdb,
                                 const dav_resource *resource,
                                 const dav_locktoken_list *ltl,
                                 time_t new_time,
                                 dav_lock **locks);

    /*
    ** Look up the resource associated with a particular locktoken.
    **
    ** The search begins at the specified <start_resource> and the lock
    ** specified by <locktoken>.
    **
    ** If the resource/token specifies an indirect lock, then the direct
    ** lock will be looked up, and THAT resource will be returned. In other
    ** words, this function always returns the resource where a particular
    ** lock (token) was asserted.
    **
    ** NOTE: this function pointer is allowed to be NULL, indicating that
    **       the provider does not support this type of functionality. The
    **       caller should then traverse up the repository hierarchy looking
    **       for the resource defining a lock with this locktoken.
    */
    dav_error * (*lookup_resource)(dav_lockdb *lockdb,
                                   const dav_locktoken *locktoken,
                                   const dav_resource *start_resource,
                                   const dav_resource **resource);

    /*
    ** If a provider needs a context to associate with this hooks structure,
    ** then this field may be used. In most cases, it will just be NULL.
    */
    void *ctx;
};

/* what types of resources can be discovered by dav_get_resource_state() */
#define DAV_RESOURCE_LOCK_NULL  10    /* resource lock-null */
#define DAV_RESOURCE_NULL       11    /* resource null */
#define DAV_RESOURCE_EXISTS     12    /* resource exists */
#define DAV_RESOURCE_ERROR      13    /* an error occurred */


/* --------------------------------------------------------------------
**
** PROPERTY HANDLING
*/

typedef struct dav_propdb dav_propdb;

#define DAV_PROPDB_NONE                  0 
#define DAV_PROPDB_RO                    1
#define DAV_PROPDB_DISABLE_LOCKDISCOVERY 2 

DAV_DECLARE(dav_error *) dav_open_propdb(
    request_rec *r,
    dav_lockdb *lockdb,
    const dav_resource *resource,
    int flags,
    apr_array_header_t *ns_xlate,
    dav_propdb **propdb);

DAV_DECLARE(dav_error *) dav_popen_propdb(
    apr_pool_t *p,
    request_rec *r,
    dav_lockdb *lockdb,
    const dav_resource *resource,
    int flags,
    apr_array_header_t *ns_xlate,
    dav_propdb **propdb);


DAV_DECLARE(void) dav_close_propdb(dav_propdb *db);

DAV_DECLARE(dav_get_props_result) dav_get_props(
    dav_propdb *db,
    apr_xml_doc *doc);

DAV_DECLARE(dav_get_props_result) dav_get_allprops(
    dav_propdb *db,
    dav_prop_insert what);

DAV_DECLARE(void) dav_get_liveprop_supported(
    dav_propdb *propdb,
    const char *ns_uri,
    const char *propname,
    apr_text_header *body);

/*
** 3-phase property modification.
**
**   1) validate props. readable? unlocked? ACLs allow access?
**   2) execute operation (set/delete)
**   3) commit or rollback
**
** ### eventually, auth must be available. a ref to the request_rec (which
** ### contains the auth info) should be in the shared context struct.
**
** Each function may alter the error values and information contained within
** the context record. This should be done as an "increasing" level of
** error, rather than overwriting any previous error.
**
** Note that commit() cannot generate errors. It should simply free the
** rollback information.
**
** rollback() may generate additional errors because the rollback operation
** can sometimes fail(!).
**
** The caller should allocate an array of these, one per operation. It should
** be zero-initialized, then the db, operation, and prop fields should be
** filled in before calling dav_prop_validate. Note that the set/delete
** operations are order-dependent. For a given (logical) context, the same
** pointer must be passed to each phase.
**
** error_type is an internal value, but will have the same numeric value
** for each possible "desc" value. This allows the caller to group the
** descriptions via the error_type variable, rather than through string
** comparisons. Note that "status" does not provide enough granularity to
** differentiate/group the "desc" values.
**
** Note that the propdb will maintain some (global) context across all
** of the property change contexts. This implies that you can have only
** one open transaction per propdb.
*/
typedef struct dav_prop_ctx
{
    dav_propdb *propdb;

    apr_xml_elem *prop;             /* property to affect */

    int operation;
#define DAV_PROP_OP_SET        1    /* set a property value */
#define DAV_PROP_OP_DELETE     2    /* delete a prop value */
/* ### add a GET? */

    /* private items to the propdb */
    int is_liveprop;
    void *liveprop_ctx;
    struct dav_rollback_item *rollback;  /* optional rollback info */

    dav_error *err;                 /* error (if any) */

    /* private to mod_dav.c */
    request_rec *r;

} dav_prop_ctx;

DAV_DECLARE_NONSTD(void) dav_prop_validate(dav_prop_ctx *ctx);
DAV_DECLARE_NONSTD(void) dav_prop_exec(dav_prop_ctx *ctx);
DAV_DECLARE_NONSTD(void) dav_prop_commit(dav_prop_ctx *ctx);
DAV_DECLARE_NONSTD(void) dav_prop_rollback(dav_prop_ctx *ctx);

#define DAV_PROP_CTX_HAS_ERR(dpc)  ((dpc).err && (dpc).err->status >= 300)


/* --------------------------------------------------------------------
**
** WALKER STRUCTURE
*/

enum {
    DAV_CALLTYPE_MEMBER = 1,    /* called for a member resource */
    DAV_CALLTYPE_COLLECTION,    /* called for a collection */
    DAV_CALLTYPE_LOCKNULL       /* called for a locknull resource */
};

typedef struct
{
    /* the client-provided context */
    void *walk_ctx;

    /* pool to use for allocations in the callback */
    apr_pool_t *pool;

    /* the current resource */
    const dav_resource *resource;

    /* OUTPUT: add responses to this */
    dav_response *response;

} dav_walk_resource;

typedef struct
{
    int walk_type;
#define DAV_WALKTYPE_AUTH       0x0001  /* limit to authorized files */
#define DAV_WALKTYPE_NORMAL     0x0002  /* walk normal files */
#define DAV_WALKTYPE_LOCKNULL   0x0004  /* walk locknull resources */
#define DAV_WALKTYPE_TOLERANT   0x0008  /* tolerate non-fatal errors */

    /* callback function and a client context for the walk */
    dav_error * (*func)(dav_walk_resource *wres, int calltype);
    void *walk_ctx;

    /* what pool to use for allocations needed by walk logic */
    apr_pool_t *pool;

    /* beginning root of the walk */
    const dav_resource *root;

    /* lock database to enable walking LOCKNULL resources */
    dav_lockdb *lockdb;

} dav_walk_params;

/* directory tree walking context */
typedef struct dav_walker_ctx
{
    /* input: */
    dav_walk_params w;


    /* ### client data... phasing out this big glom */

    /* this brigade buffers data being sent to r->output_filters */
    apr_bucket_brigade *bb;

    /* a scratch pool, used to stream responses and iteratively cleared. */
    apr_pool_t *scratchpool;

    request_rec *r;                 /* original request */

    /* for PROPFIND operations */
    apr_xml_doc *doc;
    int propfind_type;
#define DAV_PROPFIND_IS_ALLPROP     1
#define DAV_PROPFIND_IS_PROPNAME    2
#define DAV_PROPFIND_IS_PROP        3

    apr_text *propstat_404;         /* (cached) propstat giving a 404 error */

    const dav_if_header *if_header; /* for validation */
    const dav_locktoken *locktoken; /* for UNLOCK */
    const dav_lock *lock;           /* for LOCK */
    int skip_root;                  /* for dav_inherit_locks() */

    int flags;

    dav_buffer work_buf;            /* for dav_validate_request() */

} dav_walker_ctx;

DAV_DECLARE(void) dav_add_response(dav_walk_resource *wres,
                                   int status,
                                   dav_get_props_result *propstats);


/* --------------------------------------------------------------------
**
** "STREAM" STRUCTURE
**
** mod_dav uses this abstraction for interacting with the repository
** while fetching/storing resources. mod_dav views resources as a stream
** of bytes.
**
** Note that the structure is opaque -- it is private to the repository
** that created the stream in the repository's "open" function.
**
** ### THIS STUFF IS GOING AWAY ... GET/read requests are handled by
** ### having the provider jam stuff straight into the filter stack.
** ### this is only left for handling PUT/write requests.
*/

typedef struct dav_stream dav_stream;

typedef enum {
    DAV_MODE_WRITE_TRUNC,      /* truncate and open for writing */
    DAV_MODE_WRITE_SEEKABLE    /* open for writing; random access */
} dav_stream_mode;


/* --------------------------------------------------------------------
**
** REPOSITORY FUNCTIONS
*/

/* Repository provider hooks */
struct dav_hooks_repository
{
    /* Flag for whether repository requires special GET handling.
     * If resources in the repository are not visible in the
     * filesystem location which URLs map to, then special handling
     * is required to first fetch a resource from the repository,
     * respond to the GET request, then free the resource copy.
     */
    int handle_get;

    /* Get a resource descriptor for the URI in a request. A descriptor
     * should always be returned even if the resource does not exist. This
     * repository has been identified as handling the resource given by
     * the URI, so an answer must be given. If there is a problem with the
     * 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.
     *
     * 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
     * resource.
     */
    dav_error * (*get_resource)(
        request_rec *r,
        const char *root_dir,
        const char *label,
        int use_checked_in,
        dav_resource **resource
    );

    /* Get a resource descriptor for the parent of the given resource.
     * The resources need not exist.  NULL is returned if the resource
     * is the root collection.
     *
     * An error should be returned only if there is a fatal error in
     * fetching information about the parent resource.
     */
    dav_error * (*get_parent_resource)(
        const dav_resource *resource,
        dav_resource **parent_resource
    );

    /* Determine whether two resource descriptors refer to the same resource.
    *
     * Result != 0 => the resources are the same.
     */
    int (*is_same_resource)(
        const dav_resource *res1,
        const dav_resource *res2
    );

    /* Determine whether one resource is a parent (immediate or otherwise)
     * of another.
     *
     * Result != 0 => res1 is a parent of res2.
     */
    int (*is_parent_resource)(
        const dav_resource *res1,
        const dav_resource *res2
    );

    /*
    ** Open a stream for this resource, using the specified mode. The
    ** stream will be returned in *stream.
    */
    dav_error * (*open_stream)(const dav_resource *resource,
                               dav_stream_mode mode,
                               dav_stream **stream);

    /*
    ** Close the specified stream.
    **
    ** mod_dav will (ideally) make sure to call this. For safety purposes,
    ** a provider should (ideally) register a cleanup function with the
    ** request pool to get this closed and cleaned up.
    **
    ** Note the possibility of an error from the close -- it is entirely
    ** feasible that the close does a "commit" of some kind, which can
    ** produce an error.
    **
    ** commit should be TRUE (non-zero) or FALSE (0) if the stream was
    ** opened for writing. This flag states whether to retain the file
    ** or not.
    ** Note: the commit flag is ignored for streams opened for reading.
    */
    dav_error * (*close_stream)(dav_stream *stream, int commit);

    /*
    ** Write data to the stream.
    **
    ** All of the bytes must be written, or an error should be returned.
    */
    dav_error * (*write_stream)(dav_stream *stream,
                                const void *buf, apr_size_t bufsize);

    /*
    ** Seek to an absolute position in the stream. This is used to support
    ** Content-Range in a GET/PUT.
    **
    ** NOTE: if this function is NULL (which is allowed), then any
    **       operations using Content-Range will be refused.
    */
    dav_error * (*seek_stream)(dav_stream *stream, apr_off_t abs_position);

    /*
    ** If a GET is processed using a stream (open_stream, read_stream)
    ** rather than via a sub-request (on get_pathname), then this function
    ** is used to provide the repository with a way to set the headers
    ** in the response.
    **
    ** This function may be called without a following deliver(), to
    ** handle a HEAD request.
    **
    ** This may be NULL if handle_get is FALSE.
    */
    dav_error * (*set_headers)(request_rec *r,
                               const dav_resource *resource);

    /*
    ** The provider should deliver the resource into the specified filter.
    ** Basically, this is the response to the GET method.
    **
    ** Note that this is called for all resources, including collections.
    ** The provider should determine what has content to deliver or not.
    **
    ** set_headers will be called prior to this function, allowing the
    ** provider to set the appropriate response headers.
    **
    ** This may be NULL if handle_get is FALSE.
    ** ### maybe toss handle_get and just use this function as the marker
    */
    dav_error * (*deliver)(const dav_resource *resource,
                           ap_filter_t *output);

    /* Create a collection resource. The resource must not already exist.
     *
     * Result == NULL if the collection was created successfully. Also, the
     * resource object is updated to reflect that the resource exists, and
     * is a collection.
     */
    dav_error * (*create_collection)(
        dav_resource *resource
    );

    /* Copy one resource to another. The destination may exist, if it is
     * versioned.
     * Handles both files and collections. Properties are copied as well.
     * If the destination exists and is versioned, the provider must update
     * the destination to have identical content to the source,
     * recursively for collections.
     * The depth argument is ignored for a file, and can be either 0 or
     * DAV_INFINITY for a collection.
     * If an error occurs in a child resource, then the return value is
     * non-NULL, and *response is set to a multistatus response.
     * If the copy is successful, the dst resource object is
     * updated to reflect that the resource exists.
     */
    dav_error * (*copy_resource)(
        const dav_resource *src,
        dav_resource *dst,
        int depth,
        dav_response **response
    );

    /* Move one resource to another. The destination must not exist.
     * Handles both files and collections. Properties are moved as well.
     * If an error occurs in a child resource, then the return value is
     * non-NULL, and *response is set to a multistatus response.
     * If the move is successful, the src and dst resource objects are
     * updated to reflect that the source no longer exists, and the
     * destination does.
     */
    dav_error * (*move_resource)(
        dav_resource *src,
        dav_resource *dst,
        dav_response **response
    );

    /* Remove a resource. Handles both files and collections.
     * Removes any associated properties as well.
     * If an error occurs in a child resource, then the return value is
     * non-NULL, and *response is set to a multistatus response.
     * If the delete is successful, the resource object is updated to
     * reflect that the resource no longer exists.
     */
    dav_error * (*remove_resource)(
        dav_resource *resource,
        dav_response **response
    );

    /* Walk a resource hierarchy.
     *
     * Iterates over the resource hierarchy specified by params->root.
     * Control of the walk and the callback are specified by 'params'.
     *
     * An error may be returned. *response will contain multistatus
     * responses (if any) suitable for the body of the error. It is also
     * possible to return NULL, yet still have multistatus responses.
     * In this case, typically the caller should return a 207 (Multistatus)
     * and the responses (in the body) as the HTTP response.
     */
    dav_error * (*walk)(const dav_walk_params *params, int depth,
                        dav_response **response);

    /* Get the entity tag for a resource */
    const char * (*getetag)(const dav_resource *resource);

    /*
    ** If a provider needs a context to associate with this hooks structure,
    ** then this field may be used. In most cases, it will just be NULL.
    */
    void *ctx;

    /* Get the request rec for a resource */
    request_rec * (*get_request_rec)(const dav_resource *resource);

    /* Get the pathname for a resource */
    const char * (*get_pathname)(const dav_resource *resource);
};


/* --------------------------------------------------------------------
**
** VERSIONING FUNCTIONS
*/


/* dav_add_vary_header
 *
 * If there were any headers in the request which require a Vary header
 * in the response, add it.
 */
DAV_DECLARE(void) dav_add_vary_header(request_rec *in_req,
                                      request_rec *out_req,
                                      const dav_resource *resource);

/*
** Flags specifying auto-versioning behavior, returned by
** the auto_versionable hook. The value returned depends
** on both the state of the resource and the value of the
** DAV:auto-versioning property for the resource.
**
** If the resource does not exist (null or lock-null),
** DAV_AUTO_VERSION_ALWAYS causes creation of a new version-controlled resource
**
** If the resource is checked in,
** DAV_AUTO_VERSION_ALWAYS causes it to be checked out always,
** DAV_AUTO_VERSION_LOCKED causes it to be checked out only when locked
**
** If the resource is checked out,
** DAV_AUTO_VERSION_ALWAYS causes it to be checked in always,
** DAV_AUTO_VERSION_LOCKED causes it to be checked in when unlocked
** (note: a provider should allow auto-checkin only for resources which
** were automatically checked out)
**
** In all cases, DAV_AUTO_VERSION_NEVER results in no auto-versioning behavior.
*/
typedef enum {
    DAV_AUTO_VERSION_NEVER,
    DAV_AUTO_VERSION_ALWAYS,
    DAV_AUTO_VERSION_LOCKED
} dav_auto_version;

/*
** This structure is used to record what auto-versioning operations
** were done to make a resource writable, so that they can be undone
** at the end of a request.
*/
typedef struct {
    int resource_versioned;             /* 1 => resource was auto-version-controlled */
    int resource_checkedout;            /* 1 => resource was auto-checked-out */
    int parent_checkedout;              /* 1 => parent was auto-checked-out */
    dav_resource *parent_resource;      /* parent resource, if it was needed */
} dav_auto_version_info;

/* Ensure that a resource is writable. If there is no versioning
 * provider, then this is essentially a no-op. Versioning repositories
 * require explicit resource creation and checkout before they can
 * be written to. If a new resource is to be created, or an existing
 * resource deleted, the parent collection must be checked out as well.
 *
 * Set the parent_only flag to only make the parent collection writable.
 * Otherwise, both parent and child are made writable as needed. If the
 * child does not exist, then a new versioned resource is created and
 * checked out.
 *
 * If auto-versioning is not enabled for a versioned resource, then an error is
 * returned, since the resource cannot be modified.
 *
 * The dav_auto_version_info structure is filled in with enough information
 * to restore both parent and child resources to the state they were in
 * before the auto-versioning operations occurred.
 */
DAV_DECLARE(dav_error *) dav_auto_checkout(
    request_rec *r,
    dav_resource *resource,
    int parent_only,
    dav_auto_version_info *av_info);

/* Revert the writability of resources back to what they were
 * before they were modified. If undo == 0, then the resource
 * modifications are maintained (i.e. they are checked in).
 * If undo != 0, then resource modifications are discarded
 * (i.e. they are unchecked out).
 *
 * Set the unlock flag to indicate that the resource is about
 * to be unlocked; it will be checked in if the resource
 * auto-versioning property indicates it should be. In this case,
 * av_info is ignored, so it can be NULL.
 *
 * The resource argument may be NULL if only the parent resource
 * was checked out (i.e. the parent_only was != 0 in the
 * dav_auto_checkout call).
 */
DAV_DECLARE(dav_error *) dav_auto_checkin(
    request_rec *r,
    dav_resource *resource,
    int undo,
    int unlock,
    dav_auto_version_info *av_info);

/*
** This structure is used to describe available reports
**
** "nmspace" should be valid XML and URL-quoted. mod_dav will place
** double-quotes around it and use it in an xmlns declaration.
*/
typedef struct {
    const char *nmspace;        /* namespace of the XML report element */
    const char *name;           /* element name for the XML report */
} dav_report_elem;


/* Versioning provider hooks */
struct dav_hooks_vsn
{
    /*
    ** MANDATORY HOOKS
    ** The following hooks are mandatory for all versioning providers;
    ** they define the functionality needed to implement "core" versioning.
    */

    /* Return supported versioning options.
     * Each dav_text item in the list will be returned as a separate
     * DAV header. Providers are advised to limit the length of an
     * individual text item to 63 characters, to conform to the limit
     * used by MS Web Folders.
     */
    void (*get_vsn_options)(apr_pool_t *p, apr_text_header *phdr);

    /* Get the value of a specific option for an OPTIONS request.
     * The option being requested is given by the parsed XML
     * element object "elem". The value of the option should be
     * appended to the "option" text object.
     */
    dav_error * (*get_option)(const dav_resource *resource,
                              const apr_xml_elem *elem,
                              apr_text_header *option);

    /* Determine whether a non-versioned (or non-existent) resource
     * is versionable. Returns != 0 if resource can be versioned.
     */
    int (*versionable)(const dav_resource *resource);

    /* Determine whether auto-versioning is enabled for a resource
     * (which may not exist, or may not be versioned). If the resource
     * is a checked-out resource, the provider must only enable
     * auto-checkin if the resource was automatically checked out.
     *
     * The value returned depends on both the state of the resource
     * and the value of its DAV:auto-version property. See the description
     * of the dav_auto_version enumeration above for the details.
     */
    dav_auto_version (*auto_versionable)(const dav_resource *resource);

    /* Put a resource under version control. If the resource already
     * exists unversioned, then it becomes the initial version of the
     * new version history, and it is replaced by a version selector
     * which targets the new version.
     *
     * If the resource does not exist, then a new version-controlled
     * resource is created which either targets an existing version (if the
     * "target" argument is not NULL), or the initial, empty version
     * in a new history resource (if the "target" argument is NULL).
     *
     * If successful, the resource object state is updated appropriately
     * (that is, changed to refer to the new version-controlled resource).
     */
    dav_error * (*vsn_control)(dav_resource *resource,
                               const char *target);

    /* Checkout a resource. If successful, the resource
     * object state is updated appropriately.
     *
     * The auto_checkout flag will be set if this checkout is being
     * done automatically, as part of some method which modifies
     * the resource. The provider must remember that the resource
     * was automatically checked out, so it can determine whether it
     * can be automatically checked in. (Auto-checkin should only be
     * enabled for resources which were automatically checked out.)
     *
     * If the working resource has a different URL from the
     * target resource, a dav_resource descriptor is returned
     * for the new working resource. Otherwise, the original
     * 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 auto_checkout,
                            int is_unreserved, int is_fork_ok,
                            int create_activity,
                            apr_array_header_t *activities,
                            dav_resource **working_resource);

    /* Uncheckout a checked-out resource. If successful, the resource
     * object state is updated appropriately.
     */
    dav_error * (*uncheckout)(dav_resource *resource);

    /* Checkin a checked-out resource. If successful, the resource
     * object state is updated appropriately, and the
     * version_resource descriptor will refer to the new version.
     * The version_resource argument can be NULL if the caller
     * is not interested in the new version resource.
     *
     * If the client has specified DAV:keep-checked-out in the checkin
     * request, then the keep_checked_out flag is set. The provider
     * should create a new version, but keep the resource in the
     * checked-out state.
     */
    dav_error * (*checkin)(dav_resource *resource,
                           int keep_checked_out,
                           dav_resource **version_resource);

    /*
    ** Return the set of reports available at this resource.
    **
    ** An array of report elements should be returned, with an end-marker
    ** element containing namespace==NULL. The value of the
    ** DAV:supported-report-set property will be constructed and
    ** returned.
    */
    dav_error * (*avail_reports)(const dav_resource *resource,
                                 const dav_report_elem **reports);

    /*
    ** Determine whether a Label header can be used
    ** with a particular report. The dav_xml_doc structure
    ** contains the parsed report request body.
    ** Returns 0 if the Label header is not allowed.
    */
    int (*report_label_header_allowed)(const apr_xml_doc *doc);

    /*
    ** Generate a report on a resource. Since a provider is free
    ** to define its own reports, and the value of request headers
    ** may affect the interpretation of a report, the request record
    ** must be passed to this routine.
    **
    ** The dav_xml_doc structure contains the parsed report request
    ** body. The report response should be generated into the specified
    ** output filter.
    **
    ** If an error occurs, and a response has not yet been generated,
    ** then an error can be returned from this function. mod_dav will
    ** construct an appropriate error response. Once some output has
    ** been placed into the filter, however, the provider should not
    ** return an error -- there is no way that mod_dav can deliver it
    ** properly.
    **
    ** ### maybe we need a way to signal an error anyways, and then
    ** ### apache can abort the connection?
    */
    dav_error * (*deliver_report)(request_rec *r,
                                  const dav_resource *resource,
                                  const apr_xml_doc *doc,
                                  ap_filter_t *output);

    /*
    ** OPTIONAL HOOKS
    ** The following hooks are optional; if not defined, then the
    ** corresponding protocol methods will be unsupported.
    */

    /*
    ** Set the state of a checked-in version-controlled resource.
    **
    ** If the request specified a version, the version resource
    ** represents that version. If the request specified a label,
    ** then "version" is NULL, and "label" is the label.
    **
    ** The depth argument is ignored for a file, and can be 0, 1, or
    ** DAV_INFINITY for a collection. The depth argument only applies
    ** with a label, not a version.
    **
    ** If an error occurs in a child resource, then the return value is
    ** non-NULL, and *response is set to a multistatus response.
    **
    ** This hook is optional; if not defined, then the UPDATE method
    ** will not be supported.
    */
    dav_error * (*update)(const dav_resource *resource,
                          const dav_resource *version,
                          const char *label,
                          int depth,
                          dav_response **response);

    /*
    ** Add a label to a version. The resource is either a specific
    ** version, or a version selector, in which case the label should
    ** be added to the current target of the version selector. The
    ** version selector cannot be checked out.
    **
    ** If replace != 0, any existing label by the same name is
    ** effectively deleted first. Otherwise, it is an error to
    ** attempt to add a label which already exists on some version
    ** of the same history resource.
    **
    ** This hook is optional; if not defined, then the LABEL method
    ** will not be supported. If it is defined, then the remove_label
    ** hook must be defined also.
    */
    dav_error * (*add_label)(const dav_resource *resource,
                             const char *label,
                             int replace);

    /*
    ** Remove a label from a version. The resource is either a specific
    ** version, or a version selector, in which case the label should
    ** be added to the current target of the version selector. The
    ** version selector cannot be checked out.
    **
    ** It is an error if no such label exists on the specified version.
    **
    ** This hook is optional, but if defined, the add_label hook
    ** must be defined also.
    */
    dav_error * (*remove_label)(const dav_resource *resource,
                                const char *label);

    /*
    ** Determine whether a null resource can be created as a workspace.
    ** The provider may restrict workspaces to certain locations.
    ** Returns 0 if the resource cannot be a workspace.
    **
    ** This hook is optional; if the provider does not support workspaces,
    ** it should be set to NULL.
    */
    int (*can_be_workspace)(const dav_resource *resource);

    /*
    ** Create a workspace resource. The resource must not already
    ** exist. Any <DAV:mkworkspace> element is passed to the provider
    ** in the "doc" structure; it may be empty.
    **
    ** If workspace creation is successful, the state of the resource
    ** object is updated appropriately.
    **
    ** This hook is optional; if the provider does not support workspaces,
    ** it should be set to NULL.
    */
    dav_error * (*make_workspace)(dav_resource *resource,
                                  apr_xml_doc *doc);

    /*
    ** Determine whether a null resource can be created as an activity.
    ** The provider may restrict activities to certain locations.
    ** Returns 0 if the resource cannot be an activity.
    **
    ** This hook is optional; if the provider does not support activities,
    ** it should be set to NULL.
    */
    int (*can_be_activity)(const dav_resource *resource);

    /*
    ** Create an activity resource. The resource must not already
    ** exist.
    **
    ** If activity creation is successful, the state of the resource
    ** object is updated appropriately.
    **
    ** This hook is optional; if the provider does not support activities,
    ** it should be set to NULL.
    */
    dav_error * (*make_activity)(dav_resource *resource);

    /*
    ** Merge a resource (tree) into target resource (tree).
    **
    ** ### more doc...
    **
    ** This hook is optional; if the provider does not support merging,
    ** then this should be set to NULL.
    */
    dav_error * (*merge)(dav_resource *target, dav_resource *source,
                         int no_auto_merge, int no_checkout,
                         apr_xml_elem *prop_elem,
                         ap_filter_t *output);

    /*
    ** If a provider needs a context to associate with this hooks structure,
    ** then this field may be used. In most cases, it will just be NULL.
    */
    void *ctx;
};


/* --------------------------------------------------------------------
**
** BINDING FUNCTIONS
*/

/* binding provider hooks */
struct dav_hooks_binding {

    /* Determine whether a resource can be the target of a binding.
     * Returns 0 if the resource cannot be a binding target.
     */
    int (*is_bindable)(const dav_resource *resource);

    /* Create a binding to a resource.
     * The resource argument is the target of the binding;
     * the binding argument must be a resource which does not already
     * exist.
     */
    dav_error * (*bind_resource)(const dav_resource *resource,
                                 dav_resource *binding);

    /*
    ** If a provider needs a context to associate with this hooks structure,
    ** then this field may be used. In most cases, it will just be NULL.
    */
    void *ctx;

};


/* --------------------------------------------------------------------
**
** SEARCH(DASL) FUNCTIONS
*/

/* search provider hooks */
struct dav_hooks_search {
    /* Set header for a OPTION method
     * An error may be returned.
     * To set a hadder, this function might call
     * apr_table_setn(r->headers_out, "DASL", dasl_optin1);
     *
     * Examples:
     * DASL: <DAV:basicsearch>
     * DASL: <http://foo.bar.com/syntax1>
     * DASL: <http://akuma.com/syntax2>
     */
    dav_error * (*set_option_head)(request_rec *r);

    /* Search resources
     * An error may be returned. *response will contain multistatus
     * responses (if any) suitable for the body of the error. It is also
     * possible to return NULL, yet still have multistatus responses.
     * In this case, typically the caller should return a 207 (Multistatus)
     * and the responses (in the body) as the HTTP response.
     */
    dav_error * (*search_resource)(request_rec *r,
                                   dav_response **response);

    /*
    ** If a provider needs a context to associate with this hooks structure,
    ** then this field may be used. In most cases, it will just be NULL.
    */
    void *ctx;

};


/* --------------------------------------------------------------------
**
** MISCELLANEOUS STUFF
*/

typedef struct {
    int propid;                          /* live property ID */
    const dav_hooks_liveprop *provider;  /* the provider defining this prop */
} dav_elem_private;

/* --------------------------------------------------------------------
**
** DAV OPTIONS
*/
#define DAV_OPTIONS_EXTENSION_GROUP "dav_options"

typedef struct dav_options_provider
{
    dav_error* (*dav_header)(request_rec *r,
                             const dav_resource *resource,
                             apr_text_header *phdr);

    dav_error* (*dav_method)(request_rec *r,
                             const dav_resource *resource,
                             apr_text_header *phdr);

    void *ctx;
} dav_options_provider;

extern DAV_DECLARE(const dav_options_provider *) dav_get_options_providers(const char *name);

extern DAV_DECLARE(void) dav_options_provider_register(apr_pool_t *p,
                               const char *name,
                               const dav_options_provider *provider);

/* --------------------------------------------------------------------
**
** DAV RESOURCE TYPE HOOKS
*/

typedef struct dav_resource_type_provider
{
    int (*get_resource_type)(const dav_resource *resource,
                  const char **name,
                  const char **uri);
} dav_resource_type_provider;

#define DAV_RESOURCE_TYPE_GROUP "dav_resource_type"

DAV_DECLARE(void) dav_resource_type_provider_register(apr_pool_t *p,
                                        const char *name,
                                    const dav_resource_type_provider *provider);

DAV_DECLARE(const dav_resource_type_provider *) dav_get_resource_type_providers(const char *name);

#ifdef __cplusplus
}
#endif

#endif /* _MOD_DAV_H_ */
/** @} */


Youez - 2016 - github.com/yon3zu
LinuXploit