netgen/libsrc/core/archive.hpp
2018-12-12 11:24:11 +01:00

780 lines
28 KiB
C++

#ifndef NETGEN_CORE_ARCHIVE_HPP
#define NETGEN_CORE_ARCHIVE_HPP
#include <complex> // for complex
#include <cstring> // for size_t, strlen
#include <fstream> // for operator<<, ifstream, ofstream, basic...
#include <functional> // for function
#include <map> // for map, _Rb_tree_iterator
#include <memory> // for __shared_ptr_access, __shared_ptr_acc...
#include <stdexcept> // for runtime_error
#include <string> // for string, operator+
#include <type_traits> // for declval, enable_if, false_type, is_co...
#include <typeinfo> // for type_info
#include <utility> // for move, swap, pair
#include <vector> // for vector
#include "ngcore_api.hpp" // for NGCORE_API, unlikely
#include "type_traits.hpp" // for all_of_tmpl
#include "version.hpp" // for VersionInfo
namespace ngcore
{
// Libraries using this archive can store their version here to implement backwards compatibility
const VersionInfo& GetLibraryVersion(const std::string& library);
void SetLibraryVersion(const std::string& library, const VersionInfo& version);
class Archive;
NGCORE_API std::string Demangle(const char* typeinfo);
namespace detail
{
// create new pointer of type T if it is default constructible, else throw
template<typename T, typename ...Rest>
T* constructIfPossible_impl(Rest... /*unused*/)
{ throw std::runtime_error(std::string(Demangle(typeid(T).name())) + " is not default constructible!"); }
template<typename T, typename= typename std::enable_if<std::is_constructible<T>::value>::type>
T* constructIfPossible_impl(int /*unused*/) { return new T; } // NOLINT
template<typename T>
T* constructIfPossible() { return constructIfPossible_impl<T>(int{}); }
//Type trait to check if a class implements a 'void DoArchive(Archive&)' function
template<typename T>
struct has_DoArchive
{
private:
template<typename T2>
static constexpr auto check(T2*) ->
typename std::is_same<decltype(std::declval<T2>().DoArchive(std::declval<Archive&>())),void>::type;
template<typename>
static constexpr std::false_type check(...);
using type = decltype(check<T>(nullptr)); // NOLINT
public:
NGCORE_API static constexpr bool value = type::value;
};
// Check if class is archivable
template<typename T>
struct is_Archivable_struct
{
private:
template<typename T2>
static constexpr auto check(T2*) ->
typename std::is_same<decltype(std::declval<Archive>() & std::declval<T2&>()),Archive&>::type;
template<typename>
static constexpr std::false_type check(...);
using type = decltype(check<T>(nullptr)); // NOLINT
public:
NGCORE_API static constexpr bool value = type::value;
};
struct ClassArchiveInfo
{
// create new object of this type and return a void* pointer that is points to the location
// of the (base)class given by type_info
std::function<void*(const std::type_info&)> creator;
// This caster takes a void* pointer to the type stored in this info and casts it to a
// void* pointer pointing to the (base)class type_info
std::function<void*(const std::type_info&, void*)> upcaster;
// This caster takes a void* pointer to the (base)class type_info and returns void* pointing
// to the type stored in this info
std::function<void*(const std::type_info&, void*)> downcaster;
};
} // namespace detail
template<typename T>
constexpr bool is_archivable = detail::is_Archivable_struct<T>::value;
// Base Archive class
class NGCORE_API Archive
{
const bool is_output;
// how many different shared_ptr/pointer have been (un)archived
int shared_ptr_count, ptr_count;
// maps for archived shared pointers and pointers
std::map<void*, int> shared_ptr2nr, ptr2nr;
// vectors for storing the unarchived (shared) pointers
std::vector<std::shared_ptr<void>> nr2shared_ptr;
std::vector<void*> nr2ptr;
// Helper class for up-/downcasting
template<typename T, typename ... Bases>
struct Caster
{
static void* tryUpcast(const std::type_info& ti, T* p);
static void* tryDowncast(const std::type_info& ti, void* p);
};
template<typename T, typename ... Bases>
friend class RegisterClassForArchive;
// Returns ClassArchiveInfo of Demangled typeid
static const detail::ClassArchiveInfo& GetArchiveRegister(const std::string& classname);
// Set ClassArchiveInfo for Demangled typeid, this is done by creating an instance of
// RegisterClassForArchive<type, bases...>
static void SetArchiveRegister(const std::string& classname, const detail::ClassArchiveInfo& info);
static bool IsRegistered(const std::string& classname);
public:
Archive() = delete;
Archive(const Archive&) = delete;
Archive(Archive&&) = delete;
Archive (bool ais_output) :
is_output(ais_output), shared_ptr_count(0), ptr_count(0) { ; }
virtual ~Archive() { ; }
Archive& operator=(const Archive&) = delete;
Archive& operator=(Archive&&) = delete;
bool Output () const { return is_output; }
bool Input () const { return !is_output; }
virtual const VersionInfo& GetVersion(const std::string& library) = 0;
// Pure virtual functions that have to be implemented by In-/OutArchive
virtual Archive & operator & (double & d) = 0;
virtual Archive & operator & (int & i) = 0;
virtual Archive & operator & (long & i) = 0;
virtual Archive & operator & (size_t & i) = 0;
virtual Archive & operator & (short & i) = 0;
virtual Archive & operator & (unsigned char & i) = 0;
virtual Archive & operator & (bool & b) = 0;
virtual Archive & operator & (std::string & str) = 0;
virtual Archive & operator & (char *& str) = 0;
// Archive std classes ================================================
template<typename T>
Archive& operator & (std::complex<T>& c)
{
if(Output())
(*this) << c.real() << c.imag();
else
{
T tmp;
(*this) & tmp;
c.real(tmp);
(*this) & tmp;
c.imag(tmp);
}
return (*this);
}
template<typename T>
Archive& operator & (std::vector<T>& v)
{
size_t size;
if(Output())
size = v.size();
(*this) & size;
if(Input())
v.resize(size);
Do(&v[0], size);
return (*this);
}
template<typename T1, typename T2>
Archive& operator& (std::map<T1, T2>& map)
{
if(Output())
{
(*this) << size_t(map.size());
for(auto& pair : map)
(*this) << pair.first << pair.second;
}
else
{
size_t size;
(*this) & size;
T1 key; T2 val;
for(size_t i = 0; i < size; i++)
{
T1 key; T2 val;
(*this) & key & val;
map[key] = val;
}
}
return (*this);
}
// Archive arrays =====================================================
// this functions can be overloaded in Archive implementations for more efficiency
template <typename T, typename = typename std::enable_if<is_archivable<T>>::type>
Archive & Do (T * data, size_t n)
{ for (size_t j = 0; j < n; j++) { (*this) & data[j]; }; return *this; }; // NOLINT
virtual Archive & Do (double * d, size_t n)
{ for (size_t j = 0; j < n; j++) { (*this) & d[j]; }; return *this; }; // NOLINT
virtual Archive & Do (int * i, size_t n)
{ for (size_t j = 0; j < n; j++) { (*this) & i[j]; }; return *this; }; // NOLINT
virtual Archive & Do (long * i, size_t n)
{ for (size_t j = 0; j < n; j++) { (*this) & i[j]; }; return *this; }; // NOLINT
virtual Archive & Do (size_t * i, size_t n)
{ for (size_t j = 0; j < n; j++) { (*this) & i[j]; }; return *this; }; // NOLINT
virtual Archive & Do (short * i, size_t n)
{ for (size_t j = 0; j < n; j++) { (*this) & i[j]; }; return *this; }; // NOLINT
virtual Archive & Do (unsigned char * i, size_t n)
{ for (size_t j = 0; j < n; j++) { (*this) & i[j]; }; return *this; }; // NOLINT
virtual Archive & Do (bool * b, size_t n)
{ for (size_t j = 0; j < n; j++) { (*this) & b[j]; }; return *this; }; // NOLINT
// Archive a class implementing a (void DoArchive(Archive&)) method =======
template<typename T, typename=std::enable_if_t<detail::has_DoArchive<T>::value>>
Archive& operator & (T& val)
{
val.DoArchive(*this); return *this;
}
// Archive shared_ptrs =================================================
template <typename T>
Archive& operator & (std::shared_ptr<T>& ptr)
{
if(Output())
{
// save -2 for nullptr
if(!ptr)
return (*this) << -2;
void* reg_ptr = ptr.get();
bool neededDowncast = false;
// Downcasting is only possible for our registered classes
if(typeid(T) != typeid(*ptr))
{
if(!IsRegistered(Demangle(typeid(*ptr).name())))
throw std::runtime_error(std::string("Archive error: Polymorphic type ")
+ Demangle(typeid(*ptr).name())
+ " not registered for archive");
reg_ptr = GetArchiveRegister(Demangle(typeid(*ptr).name())).downcaster(typeid(T), ptr.get());
// if there was a true downcast we have to store more information
if(reg_ptr != static_cast<void*>(ptr.get()) )
neededDowncast = true;
}
auto pos = shared_ptr2nr.find(reg_ptr);
// if not found store -1 and the pointer
if(pos == shared_ptr2nr.end())
{
auto p = ptr.get();
(*this) << -1;
(*this) & neededDowncast & p;
// if we did downcast we store the true type as well
if(neededDowncast)
(*this) << Demangle(typeid(*ptr).name());
shared_ptr2nr[reg_ptr] = shared_ptr_count++;
return *this;
}
// if found store the position and if it has to be downcasted and how
(*this) << pos->second << neededDowncast;
if(neededDowncast)
(*this) << Demangle(typeid(*ptr).name());
}
else // Input
{
int nr;
(*this) & nr;
// -2 restores a nullptr
if(nr == -2)
{
ptr = nullptr;
return *this;
}
// -1 restores a new shared ptr by restoring the inner pointer and creating a shared_ptr to it
if (nr == -1)
{
T* p = nullptr;
bool neededDowncast;
(*this) & neededDowncast & p;
ptr = std::shared_ptr<T>(p);
// if we did downcast we need to store a shared_ptr<void> to the true object
if(neededDowncast)
{
std::string name;
(*this) & name;
auto info = GetArchiveRegister(name);
// for this we use an aliasing constructor to create a shared pointer sharing lifetime
// with our shared ptr, but pointing to the true object
nr2shared_ptr.push_back(std::shared_ptr<void>(std::static_pointer_cast<void>(ptr),
info.downcaster(typeid(T),
ptr.get())));
}
else
nr2shared_ptr.push_back(ptr);
}
else
{
auto other = nr2shared_ptr[nr];
bool neededDowncast;
(*this) & neededDowncast;
if(neededDowncast)
{
// if there was a downcast we can expect the class to be registered (since archiving
// wouldn't have worked else)
std::string name;
(*this) & name;
auto info = GetArchiveRegister(name);
// same trick as above, create a shared ptr sharing lifetime with
// the shared_ptr<void> in the register, but pointing to our object
ptr = std::static_pointer_cast<T>(std::shared_ptr<void>(other,
info.upcaster(typeid(T),
other.get())));
}
else
ptr = std::static_pointer_cast<T>(other);
}
}
return *this;
}
// Archive pointers =======================================================
template <typename T>
Archive & operator& (T *& p)
{
if (Output())
{
// if the pointer is null store -2
if (!p)
return (*this) << -2;
void* reg_ptr = static_cast<void*>(p);
if(typeid(T) != typeid(*p))
{
if(!IsRegistered(Demangle(typeid(*p).name())))
throw std::runtime_error(std::string("Archive error: Polymorphic type ")
+ Demangle(typeid(*p).name())
+ " not registered for archive");
reg_ptr = GetArchiveRegister(Demangle(typeid(*p).name())).downcaster(typeid(T), static_cast<void*>(p));
}
auto pos = ptr2nr.find(reg_ptr);
// if the pointer is not found in the map create a new entry
if (pos == ptr2nr.end())
{
ptr2nr[reg_ptr] = ptr_count++;
if(typeid(*p) == typeid(T))
if (std::is_constructible<T>::value)
{
return (*this) << -1 & (*p);
}
else
throw std::runtime_error(std::string("Archive error: Class ") +
Demangle(typeid(*p).name()) + " does not provide a default constructor!");
else
{
// if a pointer to a base class is archived, the class hierarchy must be registered
// to avoid compile time issues we allow this behaviour only for "our" classes that
// implement a void DoArchive(Archive&) member function
// To recreate the object we need to store the true type of it
if(!IsRegistered(Demangle(typeid(*p).name())))
throw std::runtime_error(std::string("Archive error: Polymorphic type ")
+ Demangle(typeid(*p).name())
+ " not registered for archive");
return (*this) << -3 << Demangle(typeid(*p).name()) & (*p);
}
}
else
{
(*this) & pos->second;
bool downcasted = !(reg_ptr == static_cast<void*>(p) );
// store if the class has been downcasted and the name
(*this) << downcasted << Demangle(typeid(*p).name());
}
}
else
{
int nr;
(*this) & nr;
if (nr == -2) // restore a nullptr
p = nullptr;
else if (nr == -1) // create a new pointer of standard type (no virtual or multiple inheritance,...)
{
p = detail::constructIfPossible<T>();
nr2ptr.push_back(p);
(*this) & *p;
}
else if(nr == -3) // restore one of our registered classes that can have multiple inheritance,...
{
// As stated above, we want this special behaviour only for our classes that implement DoArchive
std::string name;
(*this) & name;
auto info = GetArchiveRegister(name);
// the creator creates a new object of type name, and returns a void* pointing
// to T (which may have an offset)
p = static_cast<T*>(info.creator(typeid(T)));
// we store the downcasted pointer (to be able to find it again from
// another class in a multiple inheritance tree)
nr2ptr.push_back(info.downcaster(typeid(T),p));
(*this) & *p;
}
else
{
bool downcasted;
std::string name;
(*this) & downcasted & name;
if(downcasted)
{
// if the class has been downcasted we can assume it is in the register
auto info = GetArchiveRegister(name);
p = static_cast<T*>(info.upcaster(typeid(T), nr2ptr[nr]));
}
else
p = static_cast<T*>(nr2ptr[nr]);
}
}
return *this;
}
// const ptr
template<typename T>
Archive& operator &(const T*& t)
{
return (*this) & const_cast<T*&>(t); // NOLINT
}
// Write a read only variable
template <typename T>
Archive & operator << (const T & t)
{
T ht(t);
(*this) & ht;
return *this;
}
virtual void FlushBuffer() {}
protected:
static std::map<std::string, VersionInfo>& GetLibraryVersions();
private:
template<typename T>
struct Caster<T>
{
static void* tryUpcast (const std::type_info& /*unused*/, T* /*unused*/)
{
throw std::runtime_error("Upcast not successful, some classes are not registered properly for archiving!");
}
static void* tryDowncast (const std::type_info& /*unused*/, void* /*unused*/)
{
throw std::runtime_error("Downcast not successful, some classes are not registered properly for archiving!");
}
};
template<typename T, typename B1, typename ... Brest>
struct Caster<T,B1,Brest...>
{
static void* tryUpcast(const std::type_info& ti, T* p)
{
try
{ return GetArchiveRegister(Demangle(typeid(B1).name())).upcaster(ti, static_cast<void*>(dynamic_cast<B1*>(p))); }
catch(std::exception&)
{ return Caster<T, Brest...>::tryUpcast(ti, p); }
}
static void* tryDowncast(const std::type_info& ti, void* p)
{
if(typeid(B1) == ti)
return dynamic_cast<T*>(static_cast<B1*>(p));
try
{ return GetArchiveRegister(Demangle(typeid(B1).name())).downcaster(ti, static_cast<void*>(dynamic_cast<T*>(static_cast<B1*>(p)))); }
catch(std::exception&)
{ return Caster<T, Brest...>::tryDowncast(ti, p); }
}
};
};
template<typename T, typename ... Bases>
class NGCORE_API RegisterClassForArchive
{
public:
RegisterClassForArchive()
{
static_assert(all_of_tmpl<std::is_base_of<Bases,T>::value...>,
"Variadic template arguments must be base classes of T");
detail::ClassArchiveInfo info;
info.creator = [this,&info](const std::type_info& ti) -> void*
{ return typeid(T) == ti ? detail::constructIfPossible<T>()
: Archive::Caster<T, Bases...>::tryUpcast(ti, detail::constructIfPossible<T>()); };
info.upcaster = [this](const std::type_info& ti, void* p) -> void*
{ return typeid(T) == ti ? p : Archive::Caster<T, Bases...>::tryUpcast(ti, static_cast<T*>(p)); };
info.downcaster = [this](const std::type_info& ti, void* p) -> void*
{ return typeid(T) == ti ? p : Archive::Caster<T, Bases...>::tryDowncast(ti, p); };
Archive::SetArchiveRegister(std::string(Demangle(typeid(T).name())),info);
}
};
// BinaryOutArchive ======================================================================
class NGCORE_API BinaryOutArchive : public Archive
{
size_t ptr = 0;
static constexpr size_t BUFFERSIZE = 1024;
alignas(64) char buffer[BUFFERSIZE] = {};
std::shared_ptr<std::ostream> fout;
public:
BinaryOutArchive() = delete;
BinaryOutArchive(const BinaryOutArchive&) = delete;
BinaryOutArchive(BinaryOutArchive&&) = delete;
BinaryOutArchive(std::shared_ptr<std::ostream>&& afout)
: Archive(true), fout(std::move(afout))
{
(*this) & GetLibraryVersions();
}
BinaryOutArchive(const std::string& filename)
: BinaryOutArchive(std::make_shared<std::ofstream>(filename)) {}
~BinaryOutArchive () override { FlushBuffer(); }
BinaryOutArchive& operator=(const BinaryOutArchive&) = delete;
BinaryOutArchive& operator=(BinaryOutArchive&&) = delete;
const VersionInfo& GetVersion(const std::string& library) override
{ return GetLibraryVersions()[library]; }
using Archive::operator&;
Archive & operator & (double & d) override
{ return Write(d); }
Archive & operator & (int & i) override
{ return Write(i); }
Archive & operator & (short & i) override
{ return Write(i); }
Archive & operator & (long & i) override
{ return Write(i); }
Archive & operator & (size_t & i) override
{ return Write(i); }
Archive & operator & (unsigned char & i) override
{ return Write(i); }
Archive & operator & (bool & b) override
{ return Write(b); }
Archive & operator & (std::string & str) override
{
int len = str.length();
(*this) & len;
FlushBuffer();
if(len)
fout->write (&str[0], len);
return *this;
}
Archive & operator & (char *& str) override
{
long len = str ? strlen (str) : -1;
(*this) & len;
FlushBuffer();
if(len > 0)
fout->write (&str[0], len); // NOLINT
return *this;
}
void FlushBuffer() override
{
if (ptr > 0)
{
fout->write(&buffer[0], ptr);
ptr = 0;
}
}
private:
template <typename T>
Archive & Write (T x)
{
if (unlikely(ptr > BUFFERSIZE-sizeof(T)))
{
fout->write(&buffer[0], ptr);
*reinterpret_cast<T*>(&buffer[0]) = x; // NOLINT
ptr = sizeof(T);
return *this;
}
*reinterpret_cast<T*>(&buffer[ptr]) = x; // NOLINT
ptr += sizeof(T);
return *this;
}
};
// BinaryInArchive ======================================================================
class NGCORE_API BinaryInArchive : public Archive
{
std::map<std::string, VersionInfo> vinfo{};
std::shared_ptr<std::istream> fin;
public:
BinaryInArchive (std::shared_ptr<std::istream>&& afin)
: Archive(false), fin(std::move(afin))
{
(*this) & vinfo;
}
BinaryInArchive (const std::string& filename)
: BinaryInArchive(std::make_shared<std::ifstream>(filename)) { ; }
const VersionInfo& GetVersion(const std::string& library) override
{ return vinfo[library]; }
using Archive::operator&;
Archive & operator & (double & d) override
{ Read(d); return *this; }
Archive & operator & (int & i) override
{ Read(i); return *this; }
Archive & operator & (short & i) override
{ Read(i); return *this; }
Archive & operator & (long & i) override
{ Read(i); return *this; }
Archive & operator & (size_t & i) override
{ Read(i); return *this; }
Archive & operator & (unsigned char & i) override
{ Read(i); return *this; }
Archive & operator & (bool & b) override
{ Read(b); return *this; }
Archive & operator & (std::string & str) override
{
int len;
(*this) & len;
str.resize(len);
if(len)
fin->read(&str[0], len); // NOLINT
return *this;
}
Archive & operator & (char *& str) override
{
long len;
(*this) & len;
if(len == -1)
str = nullptr;
else
{
str = new char[len+1]; // NOLINT
fin->read(&str[0], len); // NOLINT
str[len] = '\0'; // NOLINT
}
return *this;
}
Archive & Do (double * d, size_t n) override
{ fin->read(reinterpret_cast<char*>(d), n*sizeof(double)); return *this; } // NOLINT
Archive & Do (int * i, size_t n) override
{ fin->read(reinterpret_cast<char*>(i), n*sizeof(int)); return *this; } // NOLINT
Archive & Do (size_t * i, size_t n) override
{ fin->read(reinterpret_cast<char*>(i), n*sizeof(size_t)); return *this; } // NOLINT
private:
template<typename T>
inline void Read(T& val)
{ fin->read(reinterpret_cast<char*>(&val), sizeof(T)); } // NOLINT
};
// TextOutArchive ======================================================================
class NGCORE_API TextOutArchive : public Archive
{
std::shared_ptr<std::ostream> fout;
public:
TextOutArchive (std::shared_ptr<std::ostream>&& afout)
: Archive(true), fout(std::move(afout))
{
(*this) & GetLibraryVersions();
}
TextOutArchive (const std::string& filename) :
TextOutArchive(std::make_shared<std::ofstream>(filename)) { }
const VersionInfo& GetVersion(const std::string& library) override
{ return GetLibraryVersions()[library]; }
using Archive::operator&;
Archive & operator & (double & d) override
{ *fout << d << '\n'; return *this; }
Archive & operator & (int & i) override
{ *fout << i << '\n'; return *this; }
Archive & operator & (short & i) override
{ *fout << i << '\n'; return *this; }
Archive & operator & (long & i) override
{ *fout << i << '\n'; return *this; }
Archive & operator & (size_t & i) override
{ *fout << i << '\n'; return *this; }
Archive & operator & (unsigned char & i) override
{ *fout << int(i) << '\n'; return *this; }
Archive & operator & (bool & b) override
{ *fout << (b ? 't' : 'f') << '\n'; return *this; }
Archive & operator & (std::string & str) override
{
int len = str.length();
*fout << len << '\n';
if(len)
{
fout->write(&str[0], len); // NOLINT
*fout << '\n';
}
return *this;
}
Archive & operator & (char *& str) override
{
long len = str ? strlen (str) : -1;
*this & len;
if(len > 0)
{
fout->write (&str[0], len); // NOLINT
*fout << '\n';
}
return *this;
}
};
// TextInArchive ======================================================================
class NGCORE_API TextInArchive : public Archive
{
std::map<std::string, VersionInfo> vinfo{};
std::shared_ptr<std::istream> fin;
public:
TextInArchive (std::shared_ptr<std::istream>&& afin) :
Archive(false), fin(std::move(afin))
{
(*this) & vinfo;
}
TextInArchive (const std::string& filename)
: TextInArchive(std::make_shared<std::ifstream>(filename)) {}
const VersionInfo& GetVersion(const std::string& library) override
{ return vinfo[library]; }
using Archive::operator&;
Archive & operator & (double & d) override
{ *fin >> d; return *this; }
Archive & operator & (int & i) override
{ *fin >> i; return *this; }
Archive & operator & (short & i) override
{ *fin >> i; return *this; }
Archive & operator & (long & i) override
{ *fin >> i; return *this; }
Archive & operator & (size_t & i) override
{ *fin >> i; return *this; }
Archive & operator & (unsigned char & i) override
{ int _i; *fin >> _i; i = _i; return *this; }
Archive & operator & (bool & b) override
{ char c; *fin >> c; b = (c=='t'); return *this; }
Archive & operator & (std::string & str) override
{
int len;
*fin >> len;
char ch;
fin->get(ch); // '\n'
str.resize(len);
if(len)
fin->get(&str[0], len+1, '\0');
return *this;
}
Archive & operator & (char *& str) override
{
long len;
(*this) & len;
char ch;
if(len == -1)
{
str = nullptr;
return (*this);
}
str = new char[len+1]; // NOLINT
if(len)
{
fin->get(ch); // \n
fin->get(&str[0], len+1, '\0'); // NOLINT
}
str[len] = '\0'; // NOLINT
return *this;
}
};
} // namespace ngcore
#endif // NETGEN_CORE_ARCHIVE_HPP