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forked from cheng/wallet

Removed the old "is_serializable" in favor of C++20 concepts syntax.

Changed the name to "has_machine_independent_representation" for a more
intellible error explanation
This commit is contained in:
Cheng 2023-09-30 05:13:25 +00:00
parent 5f4fe3104b
commit bc3f2c9daf
No known key found for this signature in database
GPG Key ID: 571C3A9C3B9E6FCA
5 changed files with 41 additions and 43 deletions

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@ -107,7 +107,7 @@ namespace ro {
template < typename T,
typename std::enable_if<!is_sqlite3_field_type<T>::value, int >::type dummy_arg = 0 >
void bind(int i, const T& j) {
static_assert(ro::serializable<T>, "Don't know how to store this type in a database");
static_assert(ro::has_machine_independent_representation<T>, "Don't know how to store this type in a database");
(*this)->Isqlite3_bind(i, ro::serialize(j));
}
typedef Icompiled_sql::sql_result result;

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@ -61,7 +61,7 @@ namespace ristretto255 {
ro::to_base64_string, ro::is_serializable,
ro::serialize, ro::bin2hex, ro::hex2bin,
ro::bin2hex, ro::CompileSizedString,
ro::serializable;
ro::has_machine_independent_representation;
;
// a class representing ristretto255 elliptic points
class point;
@ -119,7 +119,7 @@ namespace ristretto255 {
assert(i == 0);
}
template<serializable T, typename... Args>
template<has_machine_independent_representation T, typename... Args>
hsh<hashsize>& hashinto(const T& j, Args... args) {
auto sj = ro::serialize(j);
int i = crypto_generichash_blake2b_update(
@ -134,7 +134,7 @@ namespace ristretto255 {
return *this;
}
template<serializable T> hsh<hashsize>& operator << (const T& j) {
template<has_machine_independent_representation T> hsh<hashsize>& operator << (const T& j) {
auto sj = ro::serialize(j);
auto i = crypto_generichash_blake2b_update(
&(this->st),
@ -147,7 +147,7 @@ namespace ristretto255 {
};
static_assert(!serializable<hsh<256> >, "Don't want to partially hash partial hashes");
static_assert(!has_machine_independent_representation<hsh<256> >, "Don't want to partially hash partial hashes");
// This constructs a finalized hash.
// If it has one argument, and that argument is hsh (unfinalized hash) object,
@ -194,11 +194,12 @@ namespace ristretto255 {
assert(i == 0);
if (i) throw HashReuseException();
}
template< serializable T, typename... Args>explicit hash(const T& first, Args... args) {
template< has_machine_independent_representation T, typename... Args>explicit hash(const T& first, Args... args) {
hsh<hashsize> in;
in << first;
if constexpr (sizeof...(args) > 0) {
in.hashinto(args...);
in.hashinto( args...);
}
int i = crypto_generichash_blake2b_final(
&in.st,
@ -280,6 +281,7 @@ namespace ristretto255 {
"we need 512 bit randoms to ensure our points and scalars are uniformly distributed"
);
// There should be scalar from hash, not point from hash
// libsodium already supplies a random point
int i{
crypto_core_ristretto255_from_hash(&blob[0], &(x.blob)[0]) };
assert(i == 0);
@ -434,21 +436,21 @@ namespace ristretto255 {
static_assert(ro::is_blob_field_type<point>::value);
static_assert(ro::is_blob_field_type<hash<256> >::value);
static_assert(false == ro::is_blob_field_type<char*>::value);
static_assert(ro::is_serializable<scalar&>::value);
static_assert(ro::is_serializable<hash<512>&>::value);
static_assert(ro::has_machine_independent_representation<scalar&>);
static_assert(ro::has_machine_independent_representation<hash<512>&>);
static_assert(ro::is_blob_field_type<int>::value == false);
static_assert(ro::is_serializable<unsigned int>::value);
static_assert(ro::is_serializable<char*>::value);
static_assert(ro::is_serializable<uint8_t*>::value == false); //false because uint8_t * has no inband terminator
static_assert(false == ro::is_serializable<wxString>::value && !ro::is_constructible_from_v<hash<256>, wxString>, "wxStrings are apt to convert anything to anything, with surprising and unexpected results");
static_assert(ro::is_serializable<decltype(std::declval<wxString>().ToUTF8())>::value == true);
static_assert(ro::has_machine_independent_representation<unsigned int>);
static_assert(ro::has_machine_independent_representation<char*>);
static_assert(ro::has_machine_independent_representation<uint8_t*> == false); //false because uint8_t * has no inband terminator
static_assert(false == ro::has_machine_independent_representation<wxString> && !ro::is_constructible_from_v<hash<256>, wxString>, "wxStrings are apt to convert anything to anything, with surprising and unexpected results");
static_assert(ro::has_machine_independent_representation<decltype(std::declval<wxString>().ToUTF8())> == true);
static_assert(ro::is_constructible_from_all_of<scalar, int, hash<512>, std::array<uint8_t, crypto_core_ristretto255_BYTES>>);
static_assert(ro::is_constructible_from_all_of<hash<256>, char*, short, unsigned short, hash<512>, point, scalar>, "want to be able to hash anything serializable");
static_assert(ro::is_constructible_from_all_of<hash<256>, char*, short, unsigned short, hash<512>, point, scalar>, "want to be able to hash anything has_machine_independent_representation");
static_assert(false == ro::is_constructible_from_any_of<int, scalar, point, hsh<512>, hash<256>>);
static_assert(false == ro::is_constructible_from_any_of <scalar, wxString, hash<256>, byte*>, "do not want indiscriminate casts");
static_assert(false == ro::is_constructible_from_any_of <point, wxString, hash<256>, byte*>, "do not want indiscriminate casts ");
static_assert(false == ro::is_constructible_from_v<hash<256>, float>);
static_assert(ro::is_serializable<float>::value == false);//Need to convert floats to
static_assert(ro::has_machine_independent_representation<float> == false);//Need to convert floats to
// their machine independent representation, possibly through idexp, frexp
// and DBL_MANT_DIG
static_assert(sizeof(decltype(ro::serialize(std::declval<scalar>())[0])) == 1);

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@ -59,12 +59,14 @@
// This template generates a span over an indexable byte type,
// such as a C array or an std::array, but not pointers
template < typename T>
std::enable_if_t<
!std::is_pointer<T>::value &&
sizeof(std::declval<T>()[0]) == 1,
std::span<const byte>
> serialize(const T& a) {
template<class T>
concept byte_spannable = requires (T a) {
std::size(a);
a[0];
} && sizeof(std::declval<T>()[0]) == 1;
template<byte_spannable T>
auto serialize(const T& a) {
int l;
const void* pt;
if constexpr (std::is_same_v<std::remove_cvref_t<T>, std::string>) {
@ -301,27 +303,21 @@
format being 44 digits in a base 58 representation.*/
// a compile time test to check if an object class has a machine independent representation
template <typename T, typename... Args> struct is_serializable{
template <typename U, typename... Args2>
static constexpr decltype(ro::serialize(std::declval<U>()), bool()) test() {
if constexpr (sizeof...(Args2) > 0) {
return is_serializable::template test<Args2...>();
}
else {
return true;
}
}
template <typename U, typename... Args2> static constexpr bool test(int = 0) {
return false;
}
static constexpr bool value = is_serializable::template test<T,Args...>();
template<typename T> concept has_machine_independent_representation = requires (T a) {
serialize(a);
};
template <typename T, typename... Args> static constexpr bool is_serializable() {
if constexpr (!has_machine_independent_representation<T>) return false;
else if constexpr (sizeof...(Args) > 0) return is_serializable<Args...>();
else return true;
};
template<typename... Args>
concept serializable = is_serializable<Args...>::value;
concept allserializable = is_serializable<Args...>();
static_assert( !serializable<double>
&& serializable<std::span<const byte>, char*, std::span<const char>>,
static_assert( !has_machine_independent_representation<double>
&& allserializable<std::span<const byte>, char*, std::span<const char>>,
"concepts needed");
template<class T> ro::CompileSizedString< (2 * sizeof(T))>bin2hex(const T& pt) {

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@ -28,7 +28,7 @@ namespace testbed {
using /*ristretto255::hash, ristretto255::hsh, */ristretto255::scalar,
ristretto255::point, ro::serialize, ro::bin2hex, ro::hex2bin,
ro::bin2hex, ro::fasthash, ro::CompileSizedString,
ro::base58, ro::serializable;
ro::base58, ro::has_machine_independent_representation;
static constexpr char SrcFilename[]{ "src/testbed.cpp" };

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@ -238,7 +238,7 @@ static bool checkDataConversionsProduceExpected(void){
point pt_a{ scl_a.timesBase() };
std::string str_pt_a = &(base58(pt_a))[0];
assert(base58<point>::bin(str_pt_a.c_str()) == pt_a);
hash<256> hash_b{ hash_a,str_hash_a,scl_a,str_sclr_a,pt_a,str_pt_a,33, 66ull };
hash<256> hash_b{ hash_a, str_hash_a, scl_a, str_sclr_a, pt_a, str_pt_a, 33, 66ull };
auto str_b = base58(hash_b).operator std::string();
if (str_b != "7cTScjKyUtmbvc28BV3ok51szgrQmaBa2YE5HPBcukC9e"
) {