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suyu/src/common/uuid.cpp
Morph 705f111058 common: uuid: Add hex string to UUID constructor
This allows for easily converting a hex string into a Common::UUID, which is backed by a 128 bit unsigned integer.
2021-08-04 10:45:41 -04:00

87 lines
2.4 KiB
C++

// Copyright 2018 yuzu Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#include <random>
#include <fmt/format.h>
#include "common/assert.h"
#include "common/uuid.h"
namespace Common {
namespace {
bool IsHexDigit(char c) {
return (c >= '0' && c <= '9') || (c >= 'a' && c <= 'f') || (c >= 'A' && c <= 'F');
}
u8 HexCharToByte(char c) {
if (c >= '0' && c <= '9') {
return static_cast<u8>(c - '0');
}
if (c >= 'a' && c <= 'f') {
return static_cast<u8>(c - 'a' + 10);
}
if (c >= 'A' && c <= 'F') {
return static_cast<u8>(c - 'A' + 10);
}
ASSERT_MSG(false, "{} is not a hexadecimal digit!", c);
return u8{0};
}
} // Anonymous namespace
u128 HexStringToU128(std::string_view hex_string) {
const size_t length = hex_string.length();
// Detect "0x" prefix.
const bool has_0x_prefix = length > 2 && hex_string[0] == '0' && hex_string[1] == 'x';
const size_t offset = has_0x_prefix ? 2 : 0;
// Check length.
if (length > 32 + offset) {
ASSERT_MSG(false, "hex_string has more than 32 hexadecimal characters!");
return INVALID_UUID;
}
u64 lo = 0;
u64 hi = 0;
for (size_t i = 0; i < length - offset; ++i) {
const char c = hex_string[length - 1 - i];
if (!IsHexDigit(c)) {
ASSERT_MSG(false, "{} is not a hexadecimal digit!", c);
return INVALID_UUID;
}
if (i < 16) {
lo |= u64{HexCharToByte(c)} << (i * 4);
}
if (i >= 16) {
hi |= u64{HexCharToByte(c)} << ((i - 16) * 4);
}
}
return u128{lo, hi};
}
UUID UUID::Generate() {
std::random_device device;
std::mt19937 gen(device());
std::uniform_int_distribution<u64> distribution(1, std::numeric_limits<u64>::max());
return UUID{distribution(gen), distribution(gen)};
}
std::string UUID::Format() const {
return fmt::format("{:016x}{:016x}", uuid[1], uuid[0]);
}
std::string UUID::FormatSwitch() const {
std::array<u8, 16> s{};
std::memcpy(s.data(), uuid.data(), sizeof(u128));
return fmt::format("{:02x}{:02x}{:02x}{:02x}-{:02x}{:02x}-{:02x}{:02x}-{:02x}{:02x}-{:02x}{"
":02x}{:02x}{:02x}{:02x}{:02x}",
s[0], s[1], s[2], s[3], s[4], s[5], s[6], s[7], s[8], s[9], s[10], s[11],
s[12], s[13], s[14], s[15]);
}
} // namespace Common