+++ /dev/null
-/*
- * Copyright (c) 2008 Apple Inc. All Rights Reserved.
- *
- * @APPLE_LICENSE_HEADER_START@
- *
- * This file contains Original Code and/or Modifications of Original Code
- * as defined in and that are subject to the Apple Public Source License
- * Version 2.0 (the 'License'). You may not use this file except in
- * compliance with the License. Please obtain a copy of the License at
- * http://www.opensource.apple.com/apsl/ and read it before using this
- * file.
- *
- * The Original Code and all software distributed under the License are
- * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
- * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
- * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
- * Please see the License for the specific language governing rights and
- * limitations under the License.
- *
- * @APPLE_LICENSE_HEADER_END@
- */
-
-
-//
-// Templates to support HandleObject-like objects
-//
-#ifndef _H_HANDLETEMPLATES
-#define _H_HANDLETEMPLATES
-
-#include <security_utilities/refcount.h>
-#include <security_utilities/threading.h>
-#include <security_utilities/globalizer.h>
-#include <security_cdsa_utilities/cssmerrors.h>
-#include <vector>
-
-#if __GNUC__ > 2
-#include <ext/hash_map>
-using __gnu_cxx::hash_map;
-#else
-#include <hash_map>
-#endif
-
-namespace Security
-{
-
-//
-// A TypedHandle is a trivial mixin class whose only feature is that
-// it has a *handle* whose type is of the caller's choosing. Subclasses
-// need to assign such a handle during creation.
-//
-template <class _Handle>
-struct TypedHandle
-{
-public:
- typedef _Handle Handle;
-
- static const _Handle invalidHandle = 0;
-
- _Handle handle() const { return mMyHandle; }
- bool validHandle() const { return mValid; }
-
-protected:
- TypedHandle(_Handle h);
- TypedHandle();
-
- void setHandle(_Handle h)
- {
- assert(!mValid); // guard against redefinition
- mMyHandle = h;
- mValid = true;
- }
- void clearHandle()
- {
- assert(mValid);
- mValid = false;
- }
-
-private:
- _Handle mMyHandle; // our handle value
- bool mValid; // is the handle (still) valid?
-};
-
-//
-// MappingHandle wraps a map indexed by handles of the chosen type.
-// A MappingHandle makes up its own handle based on some mechanism that you
-// know nothing about.
-//
-// Please be very careful about the limits of the object contract here.
-// We promise to invent a suitable, unique handle for each MappingHandle in
-// existence within one address space. We promise that if you hand that
-// handle to the various MappingHandle<>::find() variants, we will give you
-// back the MappingHandle that created it. We promise to throw if you pass
-// a bad handle to those MappingHandle<>::find() variants. This is the
-// entire contract.
-//
-template <class _Handle>
-class MappingHandle : public TypedHandle<_Handle>
-{
-protected:
- class State;
-
-public:
- typedef typename TypedHandle<_Handle>::Handle Handle;
- virtual ~MappingHandle()
- {
- State &st = state();
- StLock<Mutex> _(st);
- st.erase(this);
- }
-
- template <class SubType>
- static SubType &find(_Handle handle, CSSM_RETURN error);
-
- template <class Subtype>
- static Subtype &findAndLock(_Handle handle, CSSM_RETURN error);
-
- template <class Subtype>
- static Subtype &findAndKill(_Handle handle, CSSM_RETURN error);
-
- template <class Subtype>
- static RefPointer<Subtype> findRef(_Handle handle, CSSM_RETURN error);
-
- template <class Subtype>
- static RefPointer<Subtype> findRefAndLock(_Handle handle, CSSM_RETURN error);
-
- template <class Subtype>
- static RefPointer<Subtype> findRefAndKill(_Handle handle, CSSM_RETURN error);
-
- // @@@ Remove when 4003540 is fixed
- template <class Subtype>
- static void findAllRefs(std::vector<_Handle> &refs) {
- state().template findAllRefs<Subtype>(refs);
- }
-
-protected:
- virtual void lock();
- virtual bool tryLock();
-
- typedef hash_map<_Handle, MappingHandle<_Handle> *> HandleMap;
-
- MappingHandle();
-
- class State : public Mutex, public HandleMap
- {
- public:
- State();
- uint32_t nextSeq() { return ++sequence; }
-
- bool handleInUse(_Handle h);
- MappingHandle<_Handle> *find(_Handle h, CSSM_RETURN error);
- typename HandleMap::iterator locate(_Handle h, CSSM_RETURN error);
- void add(_Handle h, MappingHandle<_Handle> *obj);
- void erase(MappingHandle<_Handle> *obj);
- void erase(typename HandleMap::iterator &it);
- // @@@ Remove when 4003540 is fixed
- template <class SubType> void findAllRefs(std::vector<_Handle> &refs);
-
- private:
- uint32_t sequence;
- };
-
-private:
- //
- // Create the handle to be used by the map
- //
- void make();
-
- static ModuleNexus<typename MappingHandle<_Handle>::State> state;
-};
-
-//
-// MappingHandle class methods
-// Type-specific ways to access the map in various ways
-//
-template <class _Handle>
-template <class Subclass>
-inline Subclass &MappingHandle<_Handle>::find(_Handle handle, CSSM_RETURN error)
-{
- Subclass *sub;
- if (!(sub = dynamic_cast<Subclass *>(state().find(handle, error))))
- CssmError::throwMe(error);
- return *sub;
-}
-
-template <class _Handle>
-template <class Subclass>
-inline Subclass &MappingHandle<_Handle>::findAndLock(_Handle handle,
- CSSM_RETURN error)
-{
- for (;;) {
- typename HandleMap::iterator it = state().locate(handle, error);
- StLock<Mutex> _(state(), true); // locate() locked it
- Subclass *sub;
- if (!(sub = dynamic_cast<Subclass *>(it->second)))
- CssmError::throwMe(error); // bad type
- if (it->second->tryLock()) // try to lock it
- return *sub; // okay, go
- Thread::yield(); // object lock failed, backoff and retry
- }
-}
-
-template <class _Handle>
-template <class Subclass>
-inline Subclass &MappingHandle<_Handle>::findAndKill(_Handle handle,
- CSSM_RETURN error)
-{
- for (;;) {
- typename HandleMap::iterator it = state().locate(handle, error);
- StLock<Mutex> _(state(), true); // locate() locked it
- Subclass *sub;
- if (!(sub = dynamic_cast<Subclass *>(it->second)))
- CssmError::throwMe(error); // bad type
- if (it->second->tryLock()) { // try to lock it
- state().erase(it); // kill the handle
- return *sub; // okay, go
- }
- Thread::yield(); // object lock failed, backoff and retry
- }
-}
-
-template <class _Handle>
-template <class Subclass>
-inline RefPointer<Subclass> MappingHandle<_Handle>::findRef(_Handle handle,
- CSSM_RETURN error)
-{
- typename HandleMap::iterator it = state().locate(handle, error);
- StLock<Mutex> _(state(), true); // locate() locked it
- Subclass *sub;
- if (!(sub = dynamic_cast<Subclass *>(it->second)))
- CssmError::throwMe(error);
- return sub;
-}
-
-template <class _Handle>
-template <class Subclass>
-inline RefPointer<Subclass> MappingHandle<_Handle>::findRefAndLock(_Handle handle,
- CSSM_RETURN error)
-{
- for (;;) {
- typename HandleMap::iterator it = state().locate(handle, error);
- StLock<Mutex> _(state(), true); // locate() locked it
- Subclass *sub;
- if (!(sub = dynamic_cast<Subclass *>(it->second)))
- CssmError::throwMe(error); // bad type
- if (it->second->tryLock()) // try to lock it
- return sub; // okay, go
- Thread::yield(); // object lock failed, backoff and retry
- }
-}
-
-template <class _Handle>
-template <class Subclass>
-inline RefPointer<Subclass> MappingHandle<_Handle>::findRefAndKill(_Handle handle,
- CSSM_RETURN error)
-{
- for (;;) {
- typename HandleMap::iterator it = state().locate(handle, error);
- StLock<Mutex> _(state(), true); // locate() locked it
- Subclass *sub;
- if (!(sub = dynamic_cast<Subclass *>(it->second)))
- CssmError::throwMe(error); // bad type
- if (it->second->tryLock()) { // try to lock it
- state().erase(it); // kill the handle
- return sub; // okay, go
- }
- Thread::yield(); // object lock failed, backoff and retry
- }
-}
-
-//
-// @@@ Remove when 4003540 is fixed
-//
-// This is a hack to fix 3981388 and should NOT be used elsewhere.
-// Also, do not follow this code's example: State methods should not
-// implement type-specific behavior.
-//
-template <class _Handle>
-template <class Subtype>
-void MappingHandle<_Handle>::State::findAllRefs(std::vector<_Handle> &refs)
-{
- StLock<Mutex> _(*this);
- typename HandleMap::iterator it = (*this).begin();
- for (; it != (*this).end(); ++it)
- {
- Subtype *obj = dynamic_cast<Subtype *>(it->second);
- if (obj)
- refs.push_back(it->first);
- }
-}
-
-
-} // end namespace Security
-
-#endif //_H_HANDLETEMPLATES
projects / apple / security.git / blobdiff