All Classes Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
ScopeGuard.h
/* -*- mode: c++; indent-tabs-mode: nil -*- */
#ifndef SCOPEGUARD_H_
#define SCOPEGUARD_H_
template <class T>
class RefHolder
{
T& ref_;
public:
RefHolder(T& ref) : ref_(ref) {}
operator T& () const
{
return ref_;
}
private:
// Disable assignment - not implemented
RefHolder& operator=(const RefHolder&);
};
template <class T>
inline RefHolder<T> ByRef(T& t)
{
return RefHolder<T>(t);
}
class ScopeGuardImplBase
{
ScopeGuardImplBase& operator =(const ScopeGuardImplBase&);
protected:
~ScopeGuardImplBase()
{
}
public:
ScopeGuardImplBase(const ScopeGuardImplBase& other) throw()
: dismissed_(other.dismissed_)
{
other.Dismiss();
}
protected:
template <typename J>
static void SafeExecute(J& j) throw()
{
if (!j.dismissed_)
try
{
j.Execute();
}
catch(...)
{
}
}
mutable bool dismissed_;
public:
ScopeGuardImplBase() throw() : dismissed_(false)
{
}
void Dismiss() const throw()
{
dismissed_ = true;
}
};
typedef const ScopeGuardImplBase& ScopeGuard;
template <typename F>
class ScopeGuardImpl0 : public ScopeGuardImplBase
{
public:
static ScopeGuardImpl0<F> MakeGuard(F fun)
{
return ScopeGuardImpl0<F>(fun);
}
~ScopeGuardImpl0() throw()
{
SafeExecute(*this);
}
void Execute()
{
fun_();
}
protected:
ScopeGuardImpl0(F fun) : fun_(fun)
{
}
F fun_;
};
template <typename F>
inline ScopeGuardImpl0<F> MakeGuard(F fun)
{
return ScopeGuardImpl0<F>::MakeGuard(fun);
}
template <typename F, typename P1>
class ScopeGuardImpl1 : public ScopeGuardImplBase
{
public:
static ScopeGuardImpl1<F, P1> MakeGuard(F fun, P1 p1)
{
return ScopeGuardImpl1<F, P1>(fun, p1);
}
~ScopeGuardImpl1() throw()
{
SafeExecute(*this);
}
void Execute()
{
fun_(p1_);
}
protected:
ScopeGuardImpl1(F fun, P1 p1) : fun_(fun), p1_(p1)
{
}
F fun_;
const P1 p1_;
};
template <typename F, typename P1>
inline ScopeGuardImpl1<F, P1> MakeGuard(F fun, P1 p1)
{
return ScopeGuardImpl1<F, P1>::MakeGuard(fun, p1);
}
template <typename F, typename P1, typename P2>
class ScopeGuardImpl2: public ScopeGuardImplBase
{
public:
static ScopeGuardImpl2<F, P1, P2> MakeGuard(F fun, P1 p1, P2 p2)
{
return ScopeGuardImpl2<F, P1, P2>(fun, p1, p2);
}
~ScopeGuardImpl2() throw()
{
SafeExecute(*this);
}
void Execute()
{
fun_(p1_, p2_);
}
protected:
ScopeGuardImpl2(F fun, P1 p1, P2 p2) : fun_(fun), p1_(p1), p2_(p2)
{
}
F fun_;
const P1 p1_;
const P2 p2_;
};
template <typename F, typename P1, typename P2>
inline ScopeGuardImpl2<F, P1, P2> MakeGuard(F fun, P1 p1, P2 p2)
{
return ScopeGuardImpl2<F, P1, P2>::MakeGuard(fun, p1, p2);
}
template <typename F, typename P1, typename P2, typename P3>
class ScopeGuardImpl3 : public ScopeGuardImplBase
{
public:
static ScopeGuardImpl3<F, P1, P2, P3> MakeGuard(F fun, P1 p1, P2 p2, P3 p3)
{
return ScopeGuardImpl3<F, P1, P2, P3>(fun, p1, p2, p3);
}
~ScopeGuardImpl3() throw()
{
SafeExecute(*this);
}
void Execute()
{
fun_(p1_, p2_, p3_);
}
protected:
ScopeGuardImpl3(F fun, P1 p1, P2 p2, P3 p3) : fun_(fun), p1_(p1), p2_(p2), p3_(p3)
{
}
F fun_;
const P1 p1_;
const P2 p2_;
const P3 p3_;
};
template <typename F, typename P1, typename P2, typename P3>
inline ScopeGuardImpl3<F, P1, P2, P3> MakeGuard(F fun, P1 p1, P2 p2, P3 p3)
{
return ScopeGuardImpl3<F, P1, P2, P3>::MakeGuard(fun, p1, p2, p3);
}
//************************************************************
template <class Obj, typename MemFun>
class ObjScopeGuardImpl0 : public ScopeGuardImplBase
{
public:
static ObjScopeGuardImpl0<Obj, MemFun> MakeObjGuard(Obj& obj, MemFun memFun)
{
return ObjScopeGuardImpl0<Obj, MemFun>(obj, memFun);
}
~ObjScopeGuardImpl0() throw()
{
SafeExecute(*this);
}
void Execute()
{
(obj_.*memFun_)();
}
protected:
ObjScopeGuardImpl0(Obj& obj, MemFun memFun)
: obj_(obj), memFun_(memFun) {}
Obj& obj_;
MemFun memFun_;
};
template <class Obj, typename MemFun>
inline ObjScopeGuardImpl0<Obj, MemFun> MakeObjGuard(Obj& obj, MemFun memFun)
{
return ObjScopeGuardImpl0<Obj, MemFun>::MakeObjGuard(obj, memFun);
}
template <class Obj, typename MemFun, typename P1>
class ObjScopeGuardImpl1 : public ScopeGuardImplBase
{
public:
static ObjScopeGuardImpl1<Obj, MemFun, P1> MakeObjGuard(Obj& obj, MemFun memFun, P1 p1)
{
return ObjScopeGuardImpl1<Obj, MemFun, P1>(obj, memFun, p1);
}
~ObjScopeGuardImpl1() throw()
{
SafeExecute(*this);
}
void Execute()
{
(obj_.*memFun_)(p1_);
}
protected:
ObjScopeGuardImpl1(Obj& obj, MemFun memFun, P1 p1)
: obj_(obj), memFun_(memFun), p1_(p1) {}
Obj& obj_;
MemFun memFun_;
const P1 p1_;
};
template <class Obj, typename MemFun, typename P1>
inline ObjScopeGuardImpl1<Obj, MemFun, P1> MakeObjGuard(Obj& obj, MemFun memFun, P1 p1)
{
return ObjScopeGuardImpl1<Obj, MemFun, P1>::MakeObjGuard(obj, memFun, p1);
}
template <class Obj, typename MemFun, typename P1, typename P2>
class ObjScopeGuardImpl2 : public ScopeGuardImplBase
{
public:
static ObjScopeGuardImpl2<Obj, MemFun, P1, P2> MakeObjGuard(Obj& obj, MemFun memFun, P1 p1, P2 p2)
{
return ObjScopeGuardImpl2<Obj, MemFun, P1, P2>(obj, memFun, p1, p2);
}
~ObjScopeGuardImpl2() throw()
{
SafeExecute(*this);
}
void Execute()
{
(obj_.*memFun_)(p1_, p2_);
}
protected:
ObjScopeGuardImpl2(Obj& obj, MemFun memFun, P1 p1, P2 p2)
: obj_(obj), memFun_(memFun), p1_(p1), p2_(p2) {}
Obj& obj_;
MemFun memFun_;
const P1 p1_;
const P2 p2_;
};
template <class Obj, typename MemFun, typename P1, typename P2>
inline ObjScopeGuardImpl2<Obj, MemFun, P1, P2> MakeObjGuard(Obj& obj, MemFun memFun, P1 p1, P2 p2)
{
return ObjScopeGuardImpl2<Obj, MemFun, P1, P2>::MakeObjGuard(obj, memFun, p1, p2);
}
#define CONCATENATE_DIRECT(s1, s2) s1##s2
#define CONCATENATE(s1, s2) CONCATENATE_DIRECT(s1, s2)
#define ANONYMOUS_VARIABLE(str) CONCATENATE(str, __LINE__)
#ifdef __GNUC__
# define UNUSED_VARIABLE __attribute__((unused))
#else
# define UNUSED_VARIABLE
#endif
#define ON_BLOCK_EXIT ScopeGuard UNUSED_VARIABLE ANONYMOUS_VARIABLE(scopeGuard) = MakeGuard
#define ON_BLOCK_EXIT_OBJ ScopeGuard UNUSED_VARIABLE ANONYMOUS_VARIABLE(scopeGuard) = MakeObjGuard
#endif //SCOPEGUARD_H_