vn-verdnaturachat/ios/Pods/Folly/folly/detail/UniqueInstance.cpp

110 lines
2.8 KiB
C++

/*
* Copyright (c) Facebook, Inc. and its affiliates.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <folly/detail/UniqueInstance.h>
#include <cstdlib>
#include <iostream>
#include <sstream>
#include <stdexcept>
#include <string>
#include <folly/Demangle.h>
#include <folly/lang/Exception.h>
namespace folly {
namespace detail {
namespace {
using Ptr = std::type_info const*;
struct PtrRange {
Ptr const* b;
Ptr const* e;
};
template <typename Value>
PtrRange ptr_range_key(Value value) {
auto const data = value.ptrs;
return {data, data + value.key_size};
}
template <typename Value>
PtrRange ptr_range_mapped(Value value) {
auto const data = value.ptrs + value.key_size;
return {data, data + value.mapped_size};
}
bool equal(PtrRange lhs, PtrRange rhs) {
auto const cmp = [](auto a, auto b) { return *a == *b; };
return std::equal(lhs.b, lhs.e, rhs.b, rhs.e, cmp);
}
std::string join(PtrRange types) {
std::ostringstream ret;
for (auto t = types.b; t != types.e; ++t) {
if (t != types.b) {
ret << ", ";
}
ret << demangle((*t)->name());
}
return ret.str();
}
template <typename Value>
std::string render(Value value) {
auto const key_s = join(ptr_range_key(value));
auto const mapped_s = join(ptr_range_mapped(value));
std::ostringstream ret;
ret << value.tmpl << "<" << key_s << ", " << mapped_s << ">";
return ret.str();
}
} // namespace
void UniqueInstance::enforce(
char const* tmpl,
Ptr const* ptrs,
std::uint32_t key_size,
std::uint32_t mapped_size,
Value& global) noexcept {
Value const local{tmpl, ptrs, key_size, mapped_size};
if (!global.tmpl) {
global = local;
return;
}
if (!equal(ptr_range_key(global), ptr_range_key(local))) {
throw_exception<std::logic_error>("mismatched unique instance");
}
if (std::strcmp(global.tmpl, local.tmpl) == 0 &&
equal(ptr_range_mapped(global), ptr_range_mapped(local))) {
return;
}
auto const key = ptr_range_key(local);
std::ios_base::Init io_init;
std::cerr << "Overloaded unique instance over <" << join(key) << ", ...> "
<< "with differing trailing arguments:\n"
<< " " << render(global) << "\n"
<< " " << render(local) << "\n";
std::abort();
}
} // namespace detail
} // namespace folly