Roxen.git/ server/ base_server/ module.pike

2004-05-04

2004-05-04 15:02:20 by Martin Stjernholm <mast@lysator.liu.se>

• 0ddcaeb818f90bf6d6c6b496075c9bd75fe95745 (189 lines) (+121/-68) ^{[ Show | Annotate ]}
  Branch: 5.2

Generalized the default lock implementation. Some smaller optimizations.

Rev: server/base_server/module.pike:1.174
Rev: server/base_server/prototypes.pike:1.97

1:   // This file is part of Roxen WebServer.   // Copyright © 1996 - 2001, Roxen IS. - // $Id: module.pike,v 1.173 2004/05/04 14:38:57 grubba Exp $ + // $Id: module.pike,v 1.174 2004/05/04 15:02:20 mast Exp $      #include <module_constants.h>   #include <module.h>
558:    return 0;   }    - //! Mapping from canonical path to a mapping from username to the lock - //! that apply to the path. + string resource_id (string path, RequestID id) + //! Return a string that within the filesystem uniquely identifies the + //! resource on @[path] in the given request. This is commonly @[path] + //! itself but can be extended with e.g. language, user or some form + //! variable if the path is mapped to different files according to + //! those fields.   //! - //! The @expr{0@} username is the anonymous user. + //! The important criteria here is that every unique returned string + //! corresponds to a resource that can be changed independently of + //! every other. Thus e.g. dynamic pages that evaluate to different + //! results depending on variables or cookies etc should _not_ be + //! mapped to more than one string by this function. It also means + //! that if files are stored in a filesystem which is case insensitive + //! then this function should normalize case differences.   //! - //! Only used internally by the default lock implementation. - static mapping(string:mapping(string:DAVLock)) file_locks = ([]); + //! This function is used e.g by the default lock implementation to + //! convert paths to resources that can be locked independently of + //! each other. There's also a notion of recursive locks there, which + //! means that a recursive lock on a certain resource identifier also + //! locks every resource whose identifier it is a prefix of. Therefore + //! it's typically necessary to ensure that every identifier ends with + //! "/" so that a recursive lock on e.g. "doc/foo" doesn't lock + //! "doc/foobar". + //! + //! @param path + //! The requested path below the filesystem location. @[path] has been + //! normalized with @[VFS.normalize_path]. + { +  return has_suffix (path, "/") ? path : path + "/"; + }    - //! Mapping from canonical path prefix to a mapping from username to - //! the lock that apply recursively to all files under that prefix. + mixed authenticated_user_id (RequestID id) + //! Return a value that uniquely identifies the user that the given + //! request is authenticated as.   //! - //! The @expr{0@} username is the anonymous user. + //! This function is e.g. used by the default lock implementation to + //! tell different users holding locks apart.   //! - //! Only used internally by the default lock implementation. - static mapping(string:mapping(string:DAVLock)) prefix_locks = ([]); + //! @note + //! The returned value is typically a string or integer, but if it + //! isn't then it must be able to compare for equality with + //! @[lfun::`==] and @[lfun::__hash]. + { +  // Leave this to the standard auth system by default. +  User uid = my_configuration()->authenticate (id); +  return uid && uid->name(); + }    -  + // Mapping from resource id to a mapping from user id to the lock + // that apply to the resource. + // + // Only used internally by the default lock implementation. + static mapping(string:mapping(mixed:DAVLock)) file_locks = ([]); +  + // Mapping from resource id to a mapping from user id to the lock + // that apply recursively to the resource and all other resources + // it's a prefix of. + // + // Only used internally by the default lock implementation. + static mapping(string:mapping(mixed:DAVLock)) prefix_locks = ([]); +  + #define LOOP_OVER_BOTH(PATH, LOCKS, CODE) \ +  do { \ +  foreach (file_locks; PATH; LOCKS) {CODE;} \ +  foreach (prefix_locks; PATH; LOCKS) {CODE;} \ +  } while (0) +    //! Find some or all locks that apply to @[path].   //!   //! @param path - //! Canonical path relative to the filesystem root. Always ends with - //! a @expr{"/"@}. + //! Path below the filesystem location. It's normalized with + //! @[VFS.normalize_path] and always ends with a @expr{"/"@}.   //!   //! @param recursive - //! If @expr{1@} also return locks under @[path]. + //! If @expr{1@} also return locks anywhere below @[path].   //!   //! @param exclude_shared   //! If @expr{1@} do not return shared locks that are held by users
612:    TRACE_ENTER(sprintf("find_locks(%O, %O, %O, X)",    path, recursive, exclude_shared), this);    +  path = resource_id (path, id); +     multiset(DAVLock) locks = (<>); -  function(mapping(string:DAVLock):void) add_locks; +  function(mapping(mixed:DAVLock):void) add_locks;       if (exclude_shared) { -  User uid = id->conf->authenticate (id); -  string auth_user = uid && uid->name(); -  add_locks = lambda (mapping(string:DAVLock) sub_locks) { +  mixed auth_user = authenticated_user_id (id); +  add_locks = lambda (mapping(mixed:DAVLock) sub_locks) {    foreach (sub_locks; string user; DAVLock lock)    if (user == auth_user ||    lock->lockscope == "DAV:exclusive")
626:    };    }    else -  add_locks = lambda (mapping(string:DAVLock) sub_locks) { +  add_locks = lambda (mapping(mixed:DAVLock) sub_locks) {    locks |= mkmultiset (values (sub_locks));    };   
635:    }       foreach(prefix_locks; -  string prefix; mapping(string:DAVLock) sub_locks) { +  string prefix; mapping(mixed:DAVLock) sub_locks) {    if (has_prefix(path, prefix)) {    add_locks (sub_locks);    break;
643:    }       if (recursive) { -  foreach(file_locks|prefix_locks; -  string prefix; mapping(string:DAVLock) sub_locks) { +  LOOP_OVER_BOTH (string prefix, mapping(mixed:DAVLock) sub_locks, {    if (has_prefix(prefix, path)) {    add_locks (sub_locks);    } -  +  });    } -  } +        add_locks = 0;   
662:   //! user the request is authenticated as.   //!   //! @param path - //! Canonical path relative to the filesystem root. Always ends with - //! a @expr{"/"@}. + //! Path below the filesystem location. It's normalized with + //! @[VFS.normalize_path] and always ends with a @expr{"/"@}.   //!   //! @param recursive   //! If @expr{1@} also check recursively under @[path] for locks.
709:       TRACE_ENTER(sprintf("check_locks(%O, %d, X)", path, recursive), this);    -  User uid = id->conf->authenticate (id); -  string auth_user = uid && uid->name(); +  path = resource_id (path, id);    -  +  mixed auth_user = authenticated_user_id (id); +     if (DAVLock lock =    file_locks[path] && file_locks[path][auth_user] ||    prefix_locks[path] && prefix_locks[path][auth_user]) {
720:    }    int(0..1) shared;    -  if (mapping(string:DAVLock) locks = file_locks[path]) { +  if (mapping(mixed:DAVLock) locks = file_locks[path]) {    foreach(locks;; DAVLock lock) {    if (lock->lockscope == "DAV:exclusive") {    TRACE_LEAVE(sprintf("Found other user's exclusive lock %O.",
733:    }       foreach(prefix_locks; -  string prefix; mapping(string:DAVLock) locks) { +  string prefix; mapping(mixed:DAVLock) locks) {    if (has_prefix(path, prefix)) {    if (DAVLock lock = locks[auth_user]) return lock;    if (!shared)    // If we've found a shared lock then we won't find an -  // exclusive one higher up. +  // exclusive one anywhere else.    foreach(locks;; DAVLock lock) {    if (lock->lockscope == "DAV:exclusive") {    TRACE_LEAVE(sprintf("Found other user's exclusive lock %O.",
760:       // We want to know if there are any locks with @[path] as prefix    // that apply to us. -  foreach(file_locks|prefix_locks; -  string prefix; mapping(string:DAVLock) locks) { +  LOOP_OVER_BOTH (string prefix, mapping(mixed:DAVLock) locks, {    if (has_prefix(prefix, path)) {    if (locks[auth_user])    locked_by_auth_user = 1;
776:    break;    }    } -  } +  });       TRACE_LEAVE(sprintf("Returning %O.", locked_by_auth_user ? 2 : shared));    return locked_by_auth_user ? 2 : shared;
798:   //! provided the directory it would be in exists.   //!   //! @param path - //! Canonical path that the lock applies to. It's relative to the - //! filesystem root and always ends with a @expr{"/"@}. + //! Path below the filesystem location that the lock applies to. + //! It's normalized with @[VFS.normalize_path] and always ends with + //! a @expr{"/"@}.   //!   //! @param lock   //! The lock to register.
810:   //!   //! @note   //! The default implementation supports only @expr{"DAV:write"@}. It - //! works under the assumption that every path maps to exactly one - //! file or directory (when it exists), and that the authenticated - //! user is uniquely identified by - //! @code{id->conf->authenticate(id)->name()@}. + //! uses @[resource_id] to map paths to unique resources and + //! @[authenticated_user_id] to tell users apart.   mapping(string:mixed) lock_file(string path,    DAVLock lock,    RequestID id)
821:    ASSERT_IF_DEBUG (lock->locktype == "DAV:write");    TRACE_ENTER(sprintf("lock_file(%O, lock(%O), X).", path, lock->locktoken),    this); -  User uid = id->conf->authenticate (id); -  string user = uid && uid->name(); +  path = resource_id (path, id); +  mixed auth_user = authenticated_user_id (id);    if (lock->recursive) {    if (prefix_locks[path]) { -  prefix_locks[path][user] = lock; +  prefix_locks[path][auth_user] = lock;    } else { -  prefix_locks[path] = ([ user:lock ]); +  prefix_locks[path] = ([ auth_user:lock ]);    }    } else {    if (file_locks[path]) { -  file_locks[path][user] = lock; +  file_locks[path][auth_user] = lock;    } else { -  file_locks[path] = ([ user:lock ]); +  file_locks[path] = ([ auth_user:lock ]);    }    }    TRACE_LEAVE("Ok.");
843:   //! Remove @[lock] that currently is locking the resource at @[path].   //!   //! @param path - //! Canonical path that the lock applies to. It's relative to the - //! filesystem root and always ends with a @expr{"/"@}. + //! Path below the filesystem location that the lock applies to. + //! It's normalized with @[VFS.normalize_path] and always ends with + //! a @expr{"/"@}.   //!   //! @param lock   //! The lock to unregister. (It must not be changed or destructed.)
857:   {    TRACE_ENTER(sprintf("unlock_file(%O, lock(%O), X).", path, lock->locktoken),    this); -  User uid = id->conf->authenticate (id); -  string user = uid && uid->name(); +  mixed auth_user = authenticated_user_id (id); +  path = resource_id (path, id);    DAVLock removed_lock;    if (lock->recursive) { -  removed_lock = m_delete (prefix_locks[path], user); +  removed_lock = m_delete (prefix_locks[path], auth_user);    if (!sizeof (prefix_locks[path])) m_delete (prefix_locks, path);    }    else { -  removed_lock = m_delete (file_locks[path], user); +  removed_lock = m_delete (file_locks[path], auth_user);    if (!sizeof (file_locks[path])) m_delete (file_locks, path);    } -  ASSERT_IF_DEBUG (lock /*%O*/ == removed_lock /*%O*/, lock, removed_lock); +  ASSERT_IF_DEBUG (!removed_lock || lock /*%O*/ == removed_lock /*%O*/, +  lock, removed_lock);    TRACE_LEAVE("Ok.");    return 0;   }