From 4dd47ead0e6565b5ac9c001f294b868d8a50129d Mon Sep 17 00:00:00 2001 From: Andrew Tridgell Date: Mon, 1 Jun 2015 15:15:37 +1000 Subject: [PATCH] AP_HAL: removed old fastdelegate code --- libraries/AP_HAL/AP_HAL_Namespace.h | 38 - libraries/AP_HAL/utility/FastDelegate.h | 1041 ----------------------- 2 files changed, 1079 deletions(-) delete mode 100644 libraries/AP_HAL/utility/FastDelegate.h diff --git a/libraries/AP_HAL/AP_HAL_Namespace.h b/libraries/AP_HAL/AP_HAL_Namespace.h index e90ef7a12c..cbc6ab17cc 100644 --- a/libraries/AP_HAL/AP_HAL_Namespace.h +++ b/libraries/AP_HAL/AP_HAL_Namespace.h @@ -5,52 +5,14 @@ #include #include "string.h" -#include "utility/FastDelegate.h" - -#define DELEGATE_FUNCTION_VOID_TYPEDEF(type) typedef fastdelegate::FastDelegate0 type -#define AP_HAL_CLASSPROC_VOID(classptr, func) fastdelegate::MakeDelegate(classptr, func) - -// macros to hide the details of delegate functions using FastDelegate -#define AP_HAL_CLASSPROC(classptr, func) fastdelegate::MakeDelegate(classptr, func) -#define AP_HAL_MEMBERPROC(func) AP_HAL_CLASSPROC(this, func) - -#define DELEGATE_FUNCTION0(rettype) fastdelegate::FastDelegate0 -#define DELEGATE_FUNCTION1(rettype, args...) fastdelegate::FastDelegate0 -#define DELEGATE_FUNCTION2(rettype, args...) fastdelegate::FastDelegate0 - -#define DELEGATE_FUNCTION(rettype, ...) fastdelegate::FastDelegate0 - -#if APM_BUILD_FUNCTOR #include "utility/functor.h" -// Also add the hacks for the delegate implementation. Here it's just an alias #define FUNCTOR_BIND_VOID(obj, func, rettype, ...) \ FUNCTOR_BIND(obj, func, rettype, ## __VA_ARGS__) #define FUNCTOR_TYPEDEF_VOID(name, rettype, ...) \ FUNCTOR_TYPEDEF(name, rettype, ## __VA_ARGS__) -#else -#define FUNCTOR_TYPEDEF(name, rettype, ...) \ - typedef DELEGATE_FUNCTION(rettype, ## __VA_ARGS__) name - -#define FUNCTOR_DECLARE(name, rettype, ...) \ - DELEGATE_FUNCTION(rettype, ## __VA_ARGS__) name - -#define FUNCTOR_BIND(obj, func, rettype, ...) \ - AP_HAL_CLASSPROC(obj, func) - -#define FUNCTOR_BIND_MEMBER(func, rettype, ...) \ - AP_HAL_MEMBERPROC(func) - -#define FUNCTOR_BIND_VOID(obj, func, rettype, ...) \ - AP_HAL_CLASSPROC_VOID(obj, func) - -#define FUNCTOR_TYPEDEF_VOID(name, rettype, ...) \ - DELEGATE_FUNCTION_VOID_TYPEDEF(name) - -#endif - namespace AP_HAL { /* Toplevel pure virtual class Hal.*/ diff --git a/libraries/AP_HAL/utility/FastDelegate.h b/libraries/AP_HAL/utility/FastDelegate.h deleted file mode 100644 index 87e15d3563..0000000000 --- a/libraries/AP_HAL/utility/FastDelegate.h +++ /dev/null @@ -1,1041 +0,0 @@ -// FastDelegate.h -// Efficient delegates in C++ that generate only two lines of asm code! -// Documentation is found at http://www.codeproject.com/cpp/FastDelegate.asp -// -// - Don Clugston, Mar 2004. -// Major contributions were made by Jody Hagins. -// History: -// 24-Apr-04 1.0 * Submitted to CodeProject. -// 28-Apr-04 1.1 * Prevent most unsafe uses of evil static function hack. -// * Improved syntax for horrible_cast (thanks Paul Bludov). -// * Tested on Metrowerks MWCC and Intel ICL (IA32) -// * Compiled, but not run, on Comeau C++ and Intel Itanium ICL. -// 27-Jun-04 1.2 * Now works on Borland C++ Builder 5.5 -// * Now works on /clr "managed C++" code on VC7, VC7.1 -// * Comeau C++ now compiles without warnings. -// * Prevent the virtual inheritance case from being used on -// VC6 and earlier, which generate incorrect code. -// * Improved warning and error messages. Non-standard hacks -// now have compile-time checks to make them safer. -// * implicit_cast used instead of static_cast in many cases. -// * If calling a const member function, a const class pointer can be used. -// * MakeDelegate() global helper function added to simplify pass-by-value. -// * Added fastdelegate.clear() -// 16-Jul-04 1.2.1* Workaround for gcc bug (const member function pointers in templates) -// 30-Oct-04 1.3 * Support for (non-void) return values. -// * No more workarounds in client code! -// MSVC and Intel now use a clever hack invented by John Dlugosz: -// - The FASTDELEGATEDECLARE workaround is no longer necessary. -// - No more warning messages for VC6 -// * Less use of macros. Error messages should be more comprehensible. -// * Added include guards -// * Added FastDelegate::empty() to test if invocation is safe (Thanks Neville Franks). -// * Now tested on VS 2005 Express Beta, PGI C++ -// 24-Dec-04 1.4 * Added DelegateMemento, to allow collections of disparate delegates. -// * <,>,<=,>= comparison operators to allow storage in ordered containers. -// * Substantial reduction of code size, especially the 'Closure' class. -// * Standardised all the compiler-specific workarounds. -// * MFP conversion now works for CodePlay (but not yet supported in the full code). -// * Now compiles without warnings on _any_ supported compiler, including BCC 5.5.1 -// * New syntax: FastDelegate< int (char *, double) >. -// 14-Feb-05 1.4.1* Now treats =0 as equivalent to .clear(), ==0 as equivalent to .empty(). (Thanks elfric). -// * Now tested on Intel ICL for AMD64, VS2005 Beta for AMD64 and Itanium. -// 30-Mar-05 1.5 * Safebool idiom: "if (dg)" is now equivalent to "if (!dg.empty())" -// * Fully supported by CodePlay VectorC -// * Bugfix for Metrowerks: empty() was buggy because a valid MFP can be 0 on MWCC! -// * More optimal assignment,== and != operators for static function pointers. - -#ifndef FASTDELEGATE_H -#define FASTDELEGATE_H -#if defined(_MSC_VER) && (_MSC_VER > 1000) -#pragma once -#endif // _MSC_VER > 1000 - -//#include // to allow <,> comparisons - -//////////////////////////////////////////////////////////////////////////////// -// Configuration options -// -//////////////////////////////////////////////////////////////////////////////// - -// Uncomment the following #define for optimally-sized delegates. -// In this case, the generated asm code is almost identical to the code you'd get -// if the compiler had native support for delegates. -// It will not work on systems where sizeof(dataptr) < sizeof(codeptr). -// Thus, it will not work for DOS compilers using the medium model. -// It will also probably fail on some DSP systems. -#define FASTDELEGATE_USESTATICFUNCTIONHACK - -// Uncomment the next line to allow function declarator syntax. -// It is automatically enabled for those compilers where it is known to work. -//#define FASTDELEGATE_ALLOW_FUNCTION_TYPE_SYNTAX - -//////////////////////////////////////////////////////////////////////////////// -// Compiler identification for workarounds -// -//////////////////////////////////////////////////////////////////////////////// - -// Compiler identification. It's not easy to identify Visual C++ because -// many vendors fraudulently define Microsoft's identifiers. -#if defined(_MSC_VER) && !defined(__MWERKS__) && !defined(__VECTOR_C) && !defined(__ICL) && !defined(__BORLANDC__) -#define FASTDLGT_ISMSVC - -#if (_MSC_VER <1300) // Many workarounds are required for VC6. -#define FASTDLGT_VC6 -#pragma warning(disable:4786) // disable this ridiculous warning -#endif - -#endif - -// Does the compiler uses Microsoft's member function pointer structure? -// If so, it needs special treatment. -// Metrowerks CodeWarrior, Intel, and CodePlay fraudulently define Microsoft's -// identifier, _MSC_VER. We need to filter Metrowerks out. -#if defined(_MSC_VER) && !defined(__MWERKS__) -#define FASTDLGT_MICROSOFT_MFP - -#if !defined(__VECTOR_C) -// CodePlay doesn't have the __single/multi/virtual_inheritance keywords -#define FASTDLGT_HASINHERITANCE_KEYWORDS -#endif -#endif - -// Does it allow function declarator syntax? The following compilers are known to work: -#if defined(FASTDLGT_ISMSVC) && (_MSC_VER >=1310) // VC 7.1 -#define FASTDELEGATE_ALLOW_FUNCTION_TYPE_SYNTAX -#endif - -// Gcc(2.95+), and versions of Digital Mars, Intel and Comeau in common use. -#if defined (__DMC__) || defined(__GNUC__) || defined(__ICL) || defined(__COMO__) -#define FASTDELEGATE_ALLOW_FUNCTION_TYPE_SYNTAX -#endif - -// It works on Metrowerks MWCC 3.2.2. From boost.Config it should work on earlier ones too. -#if defined (__MWERKS__) -#define FASTDELEGATE_ALLOW_FUNCTION_TYPE_SYNTAX -#endif - -#ifdef __GNUC__ // Workaround GCC bug #8271 - // At present, GCC doesn't recognize constness of MFPs in templates -#define FASTDELEGATE_GCC_BUG_8271 -#endif - - - -//////////////////////////////////////////////////////////////////////////////// -// General tricks used in this code -// -// (a) Error messages are generated by typdefing an array of negative size to -// generate compile-time errors. -// (b) Warning messages on MSVC are generated by declaring unused variables, and -// enabling the "variable XXX is never used" warning. -// (c) Unions are used in a few compiler-specific cases to perform illegal casts. -// (d) For Microsoft and Intel, when adjusting the 'this' pointer, it's cast to -// (char *) first to ensure that the correct number of *bytes* are added. -// -//////////////////////////////////////////////////////////////////////////////// -// Helper templates -// -//////////////////////////////////////////////////////////////////////////////// - - -namespace fastdelegate { -namespace detail { // we'll hide the implementation details in a nested namespace. - -// implicit_cast< > -// I believe this was originally going to be in the C++ standard but -// was left out by accident. It's even milder than static_cast. -// I use it instead of static_cast<> to emphasize that I'm not doing -// anything nasty. -// Usage is identical to static_cast<> -template -inline OutputClass implicit_cast(InputClass input){ - return input; -} - -// horrible_cast< > -// This is truly evil. It completely subverts C++'s type system, allowing you -// to cast from any class to any other class. Technically, using a union -// to perform the cast is undefined behaviour (even in C). But we can see if -// it is OK by checking that the union is the same size as each of its members. -// horrible_cast<> should only be used for compiler-specific workarounds. -// Usage is identical to reinterpret_cast<>. - -// This union is declared outside the horrible_cast because BCC 5.5.1 -// can't inline a function with a nested class, and gives a warning. -template -union horrible_union{ - OutputClass out; - InputClass in; -}; - -template -inline OutputClass horrible_cast(const InputClass input){ - horrible_union u; - // Cause a compile-time error if in, out and u are not the same size. - // If the compile fails here, it means the compiler has peculiar - // unions which would prevent the cast from working. - typedef int ERROR_CantUseHorrible_cast[sizeof(InputClass)==sizeof(u) - && sizeof(InputClass)==sizeof(OutputClass) ? 1 : -1] __attribute((unused)); - u.in = input; - return u.out; -} - -//////////////////////////////////////////////////////////////////////////////// -// Workarounds -// -//////////////////////////////////////////////////////////////////////////////// - -// Backwards compatibility: This macro used to be necessary in the virtual inheritance -// case for Intel and Microsoft. Now it just forward-declares the class. -#define FASTDELEGATEDECLARE(CLASSNAME) class CLASSNAME; - -// Prevent use of the static function hack with the DOS medium model. -#ifdef __MEDIUM__ -#undef FASTDELEGATE_USESTATICFUNCTIONHACK -#endif - -// DefaultVoid - a workaround for 'void' templates in VC6. -// -// (1) VC6 and earlier do not allow 'void' as a default template argument. -// (2) They also doesn't allow you to return 'void' from a function. -// -// Workaround for (1): Declare a dummy type 'DefaultVoid' which we use -// when we'd like to use 'void'. We convert it into 'void' and back -// using the templates DefaultVoidToVoid<> and VoidToDefaultVoid<>. -// Workaround for (2): On VC6, the code for calling a void function is -// identical to the code for calling a non-void function in which the -// return value is never used, provided the return value is returned -// in the EAX register, rather than on the stack. -// This is true for most fundamental types such as int, enum, void *. -// Const void * is the safest option since it doesn't participate -// in any automatic conversions. But on a 16-bit compiler it might -// cause extra code to be generated, so we disable it for all compilers -// except for VC6 (and VC5). -#ifdef FASTDLGT_VC6 -// VC6 workaround -typedef const void * DefaultVoid; -#else -// On any other compiler, just use a normal void. -typedef void DefaultVoid; -#endif - -// Translate from 'DefaultVoid' to 'void'. -// Everything else is unchanged -template -struct DefaultVoidToVoid { typedef T type; }; - -template <> -struct DefaultVoidToVoid { typedef void type; }; - -// Translate from 'void' into 'DefaultVoid' -// Everything else is unchanged -template -struct VoidToDefaultVoid { typedef T type; }; - -template <> -struct VoidToDefaultVoid { typedef DefaultVoid type; }; - - - -//////////////////////////////////////////////////////////////////////////////// -// Fast Delegates, part 1: -// -// Conversion of member function pointer to a standard form -// -//////////////////////////////////////////////////////////////////////////////// - -// GenericClass is a fake class, ONLY used to provide a type. -// It is vitally important that it is never defined, so that the compiler doesn't -// think it can optimize the invocation. For example, Borland generates simpler -// code if it knows the class only uses single inheritance. - -// Compilers using Microsoft's structure need to be treated as a special case. -#ifdef FASTDLGT_MICROSOFT_MFP - -#ifdef FASTDLGT_HASINHERITANCE_KEYWORDS - // For Microsoft and Intel, we want to ensure that it's the most efficient type of MFP - // (4 bytes), even when the /vmg option is used. Declaring an empty class - // would give 16 byte pointers in this case.... - class __single_inheritance GenericClass; -#endif - // ...but for Codeplay, an empty class *always* gives 4 byte pointers. - // If compiled with the /clr option ("managed C++"), the JIT compiler thinks - // it needs to load GenericClass before it can call any of its functions, - // (compiles OK but crashes at runtime!), so we need to declare an - // empty class to make it happy. - // Codeplay and VC4 can't cope with the unknown_inheritance case either. - class GenericClass {}; -#else - class GenericClass; -#endif - -// The size of a single inheritance member function pointer. -const int SINGLE_MEMFUNCPTR_SIZE = sizeof(void (GenericClass::*)()); - -// SimplifyMemFunc< >::Convert() -// -// A template function that converts an arbitrary member function pointer into the -// simplest possible form of member function pointer, using a supplied 'this' pointer. -// According to the standard, this can be done legally with reinterpret_cast<>. -// For (non-standard) compilers which use member function pointers which vary in size -// depending on the class, we need to use knowledge of the internal structure of a -// member function pointer, as used by the compiler. Template specialization is used -// to distinguish between the sizes. Because some compilers don't support partial -// template specialisation, I use full specialisation of a wrapper struct. - -// general case -- don't know how to convert it. Force a compile failure -template -struct SimplifyMemFunc { - template - inline static GenericClass *Convert(X *pthis, XFuncType function_to_bind, - GenericMemFuncType &bound_func) { - // Unsupported member function type -- force a compile failure. - // (it's illegal to have a array with negative size). - typedef char ERROR_Unsupported_member_function_pointer_on_this_compiler[N-100] __attribute((unused)); - return 0; - } -}; - -// For compilers where all member func ptrs are the same size, everything goes here. -// For non-standard compilers, only single_inheritance classes go here. -template <> -struct SimplifyMemFunc { - template - inline static GenericClass *Convert(X *pthis, XFuncType function_to_bind, - GenericMemFuncType &bound_func) { -#if defined __DMC__ - // Digital Mars doesn't allow you to cast between abitrary PMF's, - // even though the standard says you can. The 32-bit compiler lets you - // static_cast through an int, but the DOS compiler doesn't. - bound_func = horrible_cast(function_to_bind); -#else - bound_func = reinterpret_cast(function_to_bind); -#endif - return reinterpret_cast(pthis); - } -}; - -//////////////////////////////////////////////////////////////////////////////// -// Fast Delegates, part 1b: -// -// Workarounds for Microsoft and Intel -// -//////////////////////////////////////////////////////////////////////////////// - - -// Compilers with member function pointers which violate the standard (MSVC, Intel, Codeplay), -// need to be treated as a special case. -#ifdef FASTDLGT_MICROSOFT_MFP - -// We use unions to perform horrible_casts. I would like to use #pragma pack(push, 1) -// at the start of each function for extra safety, but VC6 seems to ICE -// intermittently if you do this inside a template. - -// __multiple_inheritance classes go here -// Nasty hack for Microsoft and Intel (IA32 and Itanium) -template<> -struct SimplifyMemFunc< SINGLE_MEMFUNCPTR_SIZE + sizeof(int) > { - template - inline static GenericClass *Convert(X *pthis, XFuncType function_to_bind, - GenericMemFuncType &bound_func) { - // We need to use a horrible_cast to do this conversion. - // In MSVC, a multiple inheritance member pointer is internally defined as: - union { - XFuncType func; - struct { - GenericMemFuncType funcaddress; // points to the actual member function - int delta; // #BYTES to be added to the 'this' pointer - }s; - } u; - // Check that the horrible_cast will work - typedef int ERROR_CantUsehorrible_cast[sizeof(function_to_bind)==sizeof(u.s)? 1 : -1]; - u.func = function_to_bind; - bound_func = u.s.funcaddress; - return reinterpret_cast(reinterpret_cast(pthis) + u.s.delta); - } -}; - -// virtual inheritance is a real nuisance. It's inefficient and complicated. -// On MSVC and Intel, there isn't enough information in the pointer itself to -// enable conversion to a closure pointer. Earlier versions of this code didn't -// work for all cases, and generated a compile-time error instead. -// But a very clever hack invented by John M. Dlugosz solves this problem. -// My code is somewhat different to his: I have no asm code, and I make no -// assumptions about the calling convention that is used. - -// In VC++ and ICL, a virtual_inheritance member pointer -// is internally defined as: -struct MicrosoftVirtualMFP { - void (GenericClass::*codeptr)(); // points to the actual member function - int delta; // #bytes to be added to the 'this' pointer - int vtable_index; // or 0 if no virtual inheritance -}; -// The CRUCIAL feature of Microsoft/Intel MFPs which we exploit is that the -// m_codeptr member is *always* called, regardless of the values of the other -// members. (This is *not* true for other compilers, eg GCC, which obtain the -// function address from the vtable if a virtual function is being called). -// Dlugosz's trick is to make the codeptr point to a probe function which -// returns the 'this' pointer that was used. - -// Define a generic class that uses virtual inheritance. -// It has a trival member function that returns the value of the 'this' pointer. -struct GenericVirtualClass : virtual public GenericClass -{ - typedef GenericVirtualClass * (GenericVirtualClass::*ProbePtrType)(); - GenericVirtualClass * GetThis() { return this; } -}; - -// __virtual_inheritance classes go here -template <> -struct SimplifyMemFunc -{ - - template - inline static GenericClass *Convert(X *pthis, XFuncType function_to_bind, - GenericMemFuncType &bound_func) { - union { - XFuncType func; - GenericClass* (X::*ProbeFunc)(); - MicrosoftVirtualMFP s; - } u; - u.func = function_to_bind; - bound_func = reinterpret_cast(u.s.codeptr); - union { - GenericVirtualClass::ProbePtrType virtfunc; - MicrosoftVirtualMFP s; - } u2; - // Check that the horrible_cast<>s will work - typedef int ERROR_CantUsehorrible_cast[sizeof(function_to_bind)==sizeof(u.s) - && sizeof(function_to_bind)==sizeof(u.ProbeFunc) - && sizeof(u2.virtfunc)==sizeof(u2.s) ? 1 : -1]; - // Unfortunately, taking the address of a MF prevents it from being inlined, so - // this next line can't be completely optimised away by the compiler. - u2.virtfunc = &GenericVirtualClass::GetThis; - u.s.codeptr = u2.s.codeptr; - return (pthis->*u.ProbeFunc)(); - } -}; - -#if (_MSC_VER <1300) - -// Nasty hack for Microsoft Visual C++ 6.0 -// unknown_inheritance classes go here -// There is a compiler bug in MSVC6 which generates incorrect code in this case!! -template <> -struct SimplifyMemFunc -{ - template - inline static GenericClass *Convert(X *pthis, XFuncType function_to_bind, - GenericMemFuncType &bound_func) { - // There is an apalling but obscure compiler bug in MSVC6 and earlier: - // vtable_index and 'vtordisp' are always set to 0 in the - // unknown_inheritance case! - // This means that an incorrect function could be called!!! - // Compiling with the /vmg option leads to potentially incorrect code. - // This is probably the reason that the IDE has a user interface for specifying - // the /vmg option, but it is disabled - you can only specify /vmg on - // the command line. In VC1.5 and earlier, the compiler would ICE if it ever - // encountered this situation. - // It is OK to use the /vmg option if /vmm or /vms is specified. - - // Fortunately, the wrong function is only called in very obscure cases. - // It only occurs when a derived class overrides a virtual function declared - // in a virtual base class, and the member function - // points to the *Derived* version of that function. The problem can be - // completely averted in 100% of cases by using the *Base class* for the - // member fpointer. Ie, if you use the base class as an interface, you'll - // stay out of trouble. - // Occasionally, you might want to point directly to a derived class function - // that isn't an override of a base class. In this case, both vtable_index - // and 'vtordisp' are zero, but a virtual_inheritance pointer will be generated. - // We can generate correct code in this case. To prevent an incorrect call from - // ever being made, on MSVC6 we generate a warning, and call a function to - // make the program crash instantly. - typedef char ERROR_VC6CompilerBug[-100]; - return 0; - } -}; - - -#else - -// Nasty hack for Microsoft and Intel (IA32 and Itanium) -// unknown_inheritance classes go here -// This is probably the ugliest bit of code I've ever written. Look at the casts! -// There is a compiler bug in MSVC6 which prevents it from using this code. -template <> -struct SimplifyMemFunc -{ - template - inline static GenericClass *Convert(X *pthis, XFuncType function_to_bind, - GenericMemFuncType &bound_func) { - // The member function pointer is 16 bytes long. We can't use a normal cast, but - // we can use a union to do the conversion. - union { - XFuncType func; - // In VC++ and ICL, an unknown_inheritance member pointer - // is internally defined as: - struct { - GenericMemFuncType m_funcaddress; // points to the actual member function - int delta; // #bytes to be added to the 'this' pointer - int vtordisp; // #bytes to add to 'this' to find the vtable - int vtable_index; // or 0 if no virtual inheritance - } s; - } u; - // Check that the horrible_cast will work - typedef int ERROR_CantUsehorrible_cast[sizeof(XFuncType)==sizeof(u.s)? 1 : -1]; - u.func = function_to_bind; - bound_func = u.s.funcaddress; - int virtual_delta = 0; - if (u.s.vtable_index) { // Virtual inheritance is used - // First, get to the vtable. - // It is 'vtordisp' bytes from the start of the class. - const int * vtable = *reinterpret_cast( - reinterpret_cast(pthis) + u.s.vtordisp ); - - // 'vtable_index' tells us where in the table we should be looking. - virtual_delta = u.s.vtordisp + *reinterpret_cast( - reinterpret_cast(vtable) + u.s.vtable_index); - } - // The int at 'virtual_delta' gives us the amount to add to 'this'. - // Finally we can add the three components together. Phew! - return reinterpret_cast( - reinterpret_cast(pthis) + u.s.delta + virtual_delta); - }; -}; -#endif // MSVC 7 and greater - -#endif // MS/Intel hacks - -} // namespace detail - -//////////////////////////////////////////////////////////////////////////////// -// Fast Delegates, part 2: -// -// Define the delegate storage, and cope with static functions -// -//////////////////////////////////////////////////////////////////////////////// - -// DelegateMemento -- an opaque structure which can hold an arbitary delegate. -// It knows nothing about the calling convention or number of arguments used by -// the function pointed to. -// It supplies comparison operators so that it can be stored in STL collections. -// It cannot be set to anything other than null, nor invoked directly: -// it must be converted to a specific delegate. - -// Implementation: -// There are two possible implementations: the Safe method and the Evil method. -// DelegateMemento - Safe version -// -// This implementation is standard-compliant, but a bit tricky. -// A static function pointer is stored inside the class. -// Here are the valid values: -// +-- Static pointer --+--pThis --+-- pMemFunc-+-- Meaning------+ -// | 0 | 0 | 0 | Empty | -// | !=0 |(dontcare)| Invoker | Static function| -// | 0 | !=0 | !=0* | Method call | -// +--------------------+----------+------------+----------------+ -// * For Metrowerks, this can be 0. (first virtual function in a -// single_inheritance class). -// When stored stored inside a specific delegate, the 'dontcare' entries are replaced -// with a reference to the delegate itself. This complicates the = and == operators -// for the delegate class. - -// DelegateMemento - Evil version -// -// For compilers where data pointers are at least as big as code pointers, it is -// possible to store the function pointer in the this pointer, using another -// horrible_cast. In this case the DelegateMemento implementation is simple: -// +--pThis --+-- pMemFunc-+-- Meaning---------------------+ -// | 0 | 0 | Empty | -// | !=0 | !=0* | Static function or method call| -// +----------+------------+-------------------------------+ -// * For Metrowerks, this can be 0. (first virtual function in a -// single_inheritance class). -// Note that the Sun C++ and MSVC documentation explicitly state that they -// support static_cast between void * and function pointers. - -class DelegateMemento { -protected: - // the data is protected, not private, because many - // compilers have problems with template friends. - typedef void (detail::GenericClass::*GenericMemFuncType)(); // arbitrary MFP. - detail::GenericClass *m_pthis; - GenericMemFuncType m_pFunction; - -#if !defined(FASTDELEGATE_USESTATICFUNCTIONHACK) - typedef void (*GenericFuncPtr)(); // arbitrary code pointer - GenericFuncPtr m_pStaticFunction; -#endif - -public: -#if !defined(FASTDELEGATE_USESTATICFUNCTIONHACK) - DelegateMemento() : m_pthis(0), m_pFunction(0), m_pStaticFunction(0) {}; - void clear() { - m_pthis=0; m_pFunction=0; m_pStaticFunction=0; - } -#else - DelegateMemento() : m_pthis(0), m_pFunction(0) {}; - void clear() { m_pthis=0; m_pFunction=0; } -#endif -public: -#if !defined(FASTDELEGATE_USESTATICFUNCTIONHACK) - inline bool IsEqual (const DelegateMemento &x) const{ - // We have to cope with the static function pointers as a special case - if (m_pFunction!=x.m_pFunction) return false; - // the static function ptrs must either both be equal, or both be 0. - if (m_pStaticFunction!=x.m_pStaticFunction) return false; - if (m_pStaticFunction!=0) return m_pthis==x.m_pthis; - else return true; - } -#else // Evil Method - inline bool IsEqual (const DelegateMemento &x) const{ - return m_pthis==x.m_pthis && m_pFunction==x.m_pFunction; - } -#endif - // Provide a strict weak ordering for DelegateMementos. - inline bool IsLess(const DelegateMemento &right) const { - // deal with static function pointers first -#if !defined(FASTDELEGATE_USESTATICFUNCTIONHACK) - if (m_pStaticFunction !=0 || right.m_pStaticFunction!=0) - return m_pStaticFunction < right.m_pStaticFunction; -#endif - if (m_pthis !=right.m_pthis) return m_pthis < right.m_pthis; - // There are no ordering operators for member function pointers, - // but we can fake one by comparing each byte. The resulting ordering is - // arbitrary (and compiler-dependent), but it permits storage in ordered STL containers. - return memcmp(&m_pFunction, &right.m_pFunction, sizeof(m_pFunction)) < 0; - - } - // BUGFIX (Mar 2005): - // We can't just compare m_pFunction because on Metrowerks, - // m_pFunction can be zero even if the delegate is not empty! - inline bool operator ! () const // Is it bound to anything? - { return m_pthis==0 && m_pFunction==0; } - inline bool empty() const // Is it bound to anything? - { return m_pthis==0 && m_pFunction==0; } -public: - DelegateMemento & operator = (const DelegateMemento &right) { - SetMementoFrom(right); - return *this; - } - inline bool operator <(const DelegateMemento &right) { - return IsLess(right); - } - inline bool operator >(const DelegateMemento &right) { - return right.IsLess(*this); - } - DelegateMemento (const DelegateMemento &right) : - m_pthis(right.m_pthis), m_pFunction(right.m_pFunction) -#if !defined(FASTDELEGATE_USESTATICFUNCTIONHACK) - , m_pStaticFunction (right.m_pStaticFunction) -#endif - {} -protected: - void SetMementoFrom(const DelegateMemento &right) { - m_pFunction = right.m_pFunction; - m_pthis = right.m_pthis; -#if !defined(FASTDELEGATE_USESTATICFUNCTIONHACK) - m_pStaticFunction = right.m_pStaticFunction; -#endif - } -}; - - -// ClosurePtr<> -// -// A private wrapper class that adds function signatures to DelegateMemento. -// It's the class that does most of the actual work. -// The signatures are specified by: -// GenericMemFunc: must be a type of GenericClass member function pointer. -// StaticFuncPtr: must be a type of function pointer with the same signature -// as GenericMemFunc. -// UnvoidStaticFuncPtr: is the same as StaticFuncPtr, except on VC6 -// where it never returns void (returns DefaultVoid instead). - -// An outer class, FastDelegateN<>, handles the invoking and creates the -// necessary typedefs. -// This class does everything else. - -namespace detail { - -template < class GenericMemFunc, class StaticFuncPtr, class UnvoidStaticFuncPtr> -class ClosurePtr : public DelegateMemento { -public: - // These functions are for setting the delegate to a member function. - - // Here's the clever bit: we convert an arbitrary member function into a - // standard form. XMemFunc should be a member function of class X, but I can't - // enforce that here. It needs to be enforced by the wrapper class. - template < class X, class XMemFunc > - inline void bindmemfunc(X *pthis, XMemFunc function_to_bind ) { - m_pthis = SimplifyMemFunc< sizeof(function_to_bind) > - ::Convert(pthis, function_to_bind, m_pFunction); -#if !defined(FASTDELEGATE_USESTATICFUNCTIONHACK) - m_pStaticFunction = 0; -#endif - } - // For const member functions, we only need a const class pointer. - // Since we know that the member function is const, it's safe to - // remove the const qualifier from the 'this' pointer with a const_cast. - // VC6 has problems if we just overload 'bindmemfunc', so we give it a different name. - template < class X, class XMemFunc> - inline void bindconstmemfunc(const X *pthis, XMemFunc function_to_bind) { - m_pthis= SimplifyMemFunc< sizeof(function_to_bind) > - ::Convert(const_cast(pthis), function_to_bind, m_pFunction); -#if !defined(FASTDELEGATE_USESTATICFUNCTIONHACK) - m_pStaticFunction = 0; -#endif - } -#ifdef FASTDELEGATE_GCC_BUG_8271 // At present, GCC doesn't recognize constness of MFPs in templates - template < class X, class XMemFunc> - inline void bindmemfunc(const X *pthis, XMemFunc function_to_bind) { - bindconstmemfunc(pthis, function_to_bind); -#if !defined(FASTDELEGATE_USESTATICFUNCTIONHACK) - m_pStaticFunction = 0; -#endif - } -#endif - // These functions are required for invoking the stored function - inline GenericClass *GetClosureThis() const { return m_pthis; } - inline GenericMemFunc GetClosureMemPtr() const { return reinterpret_cast(m_pFunction); } - -// There are a few ways of dealing with static function pointers. -// There's a standard-compliant, but tricky method. -// There's also a straightforward hack, that won't work on DOS compilers using the -// medium memory model. It's so evil that I can't recommend it, but I've -// implemented it anyway because it produces very nice asm code. - -#if !defined(FASTDELEGATE_USESTATICFUNCTIONHACK) - -// ClosurePtr<> - Safe version -// -// This implementation is standard-compliant, but a bit tricky. -// I store the function pointer inside the class, and the delegate then -// points to itself. Whenever the delegate is copied, these self-references -// must be transformed, and this complicates the = and == operators. -public: - // The next two functions are for operator ==, =, and the copy constructor. - // We may need to convert the m_pthis pointers, so that - // they remain as self-references. - template< class DerivedClass > - inline void CopyFrom (DerivedClass *pParent, const DelegateMemento &x) { - SetMementoFrom(x); - if (m_pStaticFunction!=0) { - // transform self references... - m_pthis=reinterpret_cast(pParent); - } - } - // For static functions, the 'static_function_invoker' class in the parent - // will be called. The parent then needs to call GetStaticFunction() to find out - // the actual function to invoke. - template < class DerivedClass, class ParentInvokerSig > - inline void bindstaticfunc(DerivedClass *pParent, ParentInvokerSig static_function_invoker, - StaticFuncPtr function_to_bind ) { - if (function_to_bind==0) { // cope with assignment to 0 - m_pFunction=0; - } else { - bindmemfunc(pParent, static_function_invoker); - } - m_pStaticFunction=reinterpret_cast(function_to_bind); - } - inline UnvoidStaticFuncPtr GetStaticFunction() const { - return reinterpret_cast(m_pStaticFunction); - } -#else - -// ClosurePtr<> - Evil version -// -// For compilers where data pointers are at least as big as code pointers, it is -// possible to store the function pointer in the this pointer, using another -// horrible_cast. Invocation isn't any faster, but it saves 4 bytes, and -// speeds up comparison and assignment. If C++ provided direct language support -// for delegates, they would produce asm code that was almost identical to this. -// Note that the Sun C++ and MSVC documentation explicitly state that they -// support static_cast between void * and function pointers. - - template< class DerivedClass > - inline void CopyFrom (DerivedClass *pParent, const DelegateMemento &right) { - SetMementoFrom(right); - } - // For static functions, the 'static_function_invoker' class in the parent - // will be called. The parent then needs to call GetStaticFunction() to find out - // the actual function to invoke. - // ******** EVIL, EVIL CODE! ******* - template < class DerivedClass, class ParentInvokerSig> - inline void bindstaticfunc(DerivedClass *pParent, ParentInvokerSig static_function_invoker, - StaticFuncPtr function_to_bind) { - if (function_to_bind==0) { // cope with assignment to 0 - m_pFunction=0; - } else { - // We'll be ignoring the 'this' pointer, but we need to make sure we pass - // a valid value to bindmemfunc(). - bindmemfunc(pParent, static_function_invoker); - } - - // WARNING! Evil hack. We store the function in the 'this' pointer! - // Ensure that there's a compilation failure if function pointers - // and data pointers have different sizes. - // If you get this error, you need to #undef FASTDELEGATE_USESTATICFUNCTIONHACK. - typedef int ERROR_CantUseEvilMethod[sizeof(GenericClass *)==sizeof(function_to_bind) ? 1 : -1] __attribute((unused)); - m_pthis = horrible_cast(function_to_bind); - // MSVC, SunC++ and DMC accept the following (non-standard) code: -// m_pthis = static_cast(static_cast(function_to_bind)); - // BCC32, Comeau and DMC accept this method. MSVC7.1 needs __int64 instead of long -// m_pthis = reinterpret_cast(reinterpret_cast(function_to_bind)); - } - // ******** EVIL, EVIL CODE! ******* - // This function will be called with an invalid 'this' pointer!! - // We're just returning the 'this' pointer, converted into - // a function pointer! - inline UnvoidStaticFuncPtr GetStaticFunction() const { - // Ensure that there's a compilation failure if function pointers - // and data pointers have different sizes. - // If you get this error, you need to #undef FASTDELEGATE_USESTATICFUNCTIONHACK. - typedef int ERROR_CantUseEvilMethod[sizeof(UnvoidStaticFuncPtr)==sizeof(this) ? 1 : -1] __attribute((unused)); - return horrible_cast(this); - } -#endif // !defined(FASTDELEGATE_USESTATICFUNCTIONHACK) - - // Does the closure contain this static function? - inline bool IsEqualToStaticFuncPtr(StaticFuncPtr funcptr){ - if (funcptr==0) return empty(); - // For the Evil method, if it doesn't actually contain a static function, this will return an arbitrary - // value that is not equal to any valid function pointer. - else return funcptr==reinterpret_cast(GetStaticFunction()); - } -}; - - -} // namespace detail - -//////////////////////////////////////////////////////////////////////////////// -// Fast Delegates, part 3: -// -// Wrapper classes to ensure type safety -// -//////////////////////////////////////////////////////////////////////////////// - - -// Once we have the member function conversion templates, it's easy to make the -// wrapper classes. So that they will work with as many compilers as possible, -// the classes are of the form -// FastDelegate3 -// They can cope with any combination of parameters. The max number of parameters -// allowed is 8, but it is trivial to increase this limit. -// Note that we need to treat const member functions seperately. -// All this class does is to enforce type safety, and invoke the delegate with -// the correct list of parameters. - -// Because of the weird rule about the class of derived member function pointers, -// you sometimes need to apply a downcast to the 'this' pointer. -// This is the reason for the use of "implicit_cast(pthis)" in the code below. -// If CDerivedClass is derived from CBaseClass, but doesn't override SimpleVirtualFunction, -// without this trick you'd need to write: -// MyDelegate(static_cast(&d), &CDerivedClass::SimpleVirtualFunction); -// but with the trick you can write -// MyDelegate(&d, &CDerivedClass::SimpleVirtualFunction); - -// RetType is the type the compiler uses in compiling the template. For VC6, -// it cannot be void. DesiredRetType is the real type which is returned from -// all of the functions. It can be void. - -// Implicit conversion to "bool" is achieved using the safe_bool idiom, -// using member data pointers (MDP). This allows "if (dg)..." syntax -// Because some compilers (eg codeplay) don't have a unique value for a zero -// MDP, an extra padding member is added to the SafeBool struct. -// Some compilers (eg VC6) won't implicitly convert from 0 to an MDP, so -// in that case the static function constructor is not made explicit; this -// allows "if (dg==0) ..." to compile. - -//N=1 -template -class FastDelegate0 { -private: - typedef typename detail::DefaultVoidToVoid::type DesiredRetType; - typedef DesiredRetType (*StaticFunctionPtr)(Params...); - typedef RetType (*UnvoidStaticFunctionPtr)(Params...); - typedef RetType (detail::GenericClass::*GenericMemFn)(Params...); - typedef detail::ClosurePtr ClosureType; - ClosureType m_Closure; -public: - // Typedefs to aid generic programming - typedef FastDelegate0 type; - - // Construction and comparison functions - FastDelegate0() { clear(); } - FastDelegate0(const FastDelegate0 &x) { - m_Closure.CopyFrom(this, x.m_Closure); } - void operator = (const FastDelegate0 &x) { - m_Closure.CopyFrom(this, x.m_Closure); } - bool operator ==(const FastDelegate0 &x) const { - return m_Closure.IsEqual(x.m_Closure); } - bool operator !=(const FastDelegate0 &x) const { - return !m_Closure.IsEqual(x.m_Closure); } - bool operator <(const FastDelegate0 &x) const { - return m_Closure.IsLess(x.m_Closure); } - bool operator >(const FastDelegate0 &x) const { - return x.m_Closure.IsLess(m_Closure); } - // Binding to non-const member functions - template < class X, class Y > - FastDelegate0(Y *pthis, DesiredRetType (X::* function_to_bind)(Params...) ) { - m_Closure.bindmemfunc(detail::implicit_cast(pthis), function_to_bind); } - template < class X, class Y > - inline void bind(Y *pthis, DesiredRetType (X::* function_to_bind)(Params...)) { - m_Closure.bindmemfunc(detail::implicit_cast(pthis), function_to_bind); } - // Binding to const member functions. - template < class X, class Y > - FastDelegate0(const Y *pthis, DesiredRetType (X::* function_to_bind)(Params...) const) { - m_Closure.bindconstmemfunc(detail::implicit_cast(pthis), function_to_bind); } - template < class X, class Y > - inline void bind(const Y *pthis, DesiredRetType (X::* function_to_bind)(Params...) const) { - m_Closure.bindconstmemfunc(detail::implicit_cast(pthis), function_to_bind); } - // Static functions. We convert them into a member function call. - // This constructor also provides implicit conversion - FastDelegate0(DesiredRetType (*function_to_bind)(Params...) ) { - bind(function_to_bind); } - // for efficiency, prevent creation of a temporary - void operator = (DesiredRetType (*function_to_bind)(Params...) ) { - bind(function_to_bind); } - inline void bind(DesiredRetType (*function_to_bind)(Params...)) { - m_Closure.bindstaticfunc(this, &FastDelegate0::InvokeStaticFunction, - function_to_bind); } - // Invoke the delegate - RetType operator() (Params... params) const { - return (m_Closure.GetClosureThis()->*(m_Closure.GetClosureMemPtr()))(params...); } - // Implicit conversion to "bool" using the safe_bool idiom -private: - typedef struct SafeBoolStruct { - int a_data_pointer_to_this_is_0_on_buggy_compilers; - StaticFunctionPtr m_nonzero; - } UselessTypedef; - typedef StaticFunctionPtr SafeBoolStruct::*unspecified_bool_type; -public: - operator unspecified_bool_type() const { - return empty()? 0: &SafeBoolStruct::m_nonzero; - } - // necessary to allow ==0 to work despite the safe_bool idiom - inline bool operator==(StaticFunctionPtr funcptr) { - return m_Closure.IsEqualToStaticFuncPtr(funcptr); } - inline bool operator!=(StaticFunctionPtr funcptr) { - return !m_Closure.IsEqualToStaticFuncPtr(funcptr); } - inline bool operator ! () const { // Is it bound to anything? - return !m_Closure; } - inline bool empty() const { - return !m_Closure; } - void clear() { m_Closure.clear();} - // Conversion to and from the DelegateMemento storage class - const DelegateMemento & GetMemento() { return m_Closure; } - void SetMemento(const DelegateMemento &any) { m_Closure.CopyFrom(this, any); } - -private: // Invoker for static functions - RetType InvokeStaticFunction(Params... params) const { - return (*(m_Closure.GetStaticFunction()))(params...); } -}; - -//////////////////////////////////////////////////////////////////////////////// -// Fast Delegates, part 4: -// -// FastDelegate<> class (Original author: Jody Hagins) -// Allows boost::function style syntax like: -// FastDelegate< double (int, long) > -// instead of: -// FastDelegate2< int, long, double > -// -//////////////////////////////////////////////////////////////////////////////// - -#ifdef FASTDELEGATE_ALLOW_FUNCTION_TYPE_SYNTAX - -// Declare FastDelegate as a class template. It will be specialized -// later for all number of arguments. -template -class FastDelegate; - -//N=1 -// Specialization to allow use of -// FastDelegate< R ( Param1 ) > -// instead of -// FastDelegate0 < Param1, R > -template -class FastDelegate< R ( Params... ) > - // Inherit from FastDelegate0 so that it can be treated just like a FastDelegate0 - : public FastDelegate0 < R, Params... > -{ -public: - // Make using the base type a bit easier via typedef. - typedef FastDelegate0 < R, Params... > BaseType; - - // Allow users access to the specific type of this delegate. - typedef FastDelegate SelfType; - - // Mimic the base class constructors. - FastDelegate() : BaseType() { } - - template < class X, class Y > - FastDelegate(Y * pthis, - R (X::* function_to_bind)( Params... )) - : BaseType(pthis, function_to_bind) { } - - template < class X, class Y > - FastDelegate(const Y *pthis, - R (X::* function_to_bind)( Params... ) const) - : BaseType(pthis, function_to_bind) - { } - - FastDelegate(R (*function_to_bind)( Params... )) - : BaseType(function_to_bind) { } - void operator = (const BaseType &x) { - *static_cast(this) = x; } -}; - -#endif //FASTDELEGATE_ALLOW_FUNCTION_TYPE_SYNTAX - -//////////////////////////////////////////////////////////////////////////////// -// Fast Delegates, part 5: -// -// MakeDelegate() helper function -// -// MakeDelegate(&x, &X::func) returns a fastdelegate of the type -// necessary for calling x.func() with the correct number of arguments. -// This makes it possible to eliminate many typedefs from user code. -// -//////////////////////////////////////////////////////////////////////////////// - -// Also declare overloads of a MakeDelegate() global function to -// reduce the need for typedefs. -// We need seperate overloads for const and non-const member functions. -// Also, because of the weird rule about the class of derived member function pointers, -// implicit downcasts may need to be applied later to the 'this' pointer. -// That's why two classes (X and Y) appear in the definitions. Y must be implicitly -// castable to X. - -// Workaround for VC6. VC6 needs void return types converted into DefaultVoid. -// GCC 3.2 and later won't compile this unless it's preceded by 'typename', -// but VC6 doesn't allow 'typename' in this context. -// So, I have to use a macro. - -#ifdef FASTDLGT_VC6 -#define FASTDLGT_RETTYPE detail::VoidToDefaultVoid::type -#else -#define FASTDLGT_RETTYPE RetType -#endif - -//N=1 -template -FastDelegate0 MakeDelegate(Y* x, RetType (X::*func)(Params...)) { - return FastDelegate0(x, func); -} - -template -FastDelegate0 MakeDelegate(Y* x, RetType (X::*func)(Params...) const) { - return FastDelegate0(x, func); -} - -// clean up after ourselves... -#undef FASTDLGT_RETTYPE - -} // namespace fastdelegate - -#endif // !defined(FASTDELEGATE_H) -