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/*
* Copyright (C) 2019-2020 Intel Corporation
*
* SPDX-License-Identifier: MIT
*
*/
#pragma once
#include <cinttypes>
#include <cstddef>
#include <cstring>
#include <string>
namespace NEO {
constexpr size_t constLength(const char *string) {
if (nullptr == string) {
return 0U;
}
auto it = string;
for (; *it != '\0'; ++it) {
}
return it - string;
}
class ConstStringRef {
public:
constexpr ConstStringRef() {
}
constexpr ConstStringRef(const ConstStringRef &rhs) : ptr(rhs.ptr), len(rhs.len) {
}
ConstStringRef &operator=(const ConstStringRef &rhs) {
this->ptr = rhs.ptr;
this->len = rhs.len;
return *this;
}
constexpr ConstStringRef(const char &c) noexcept
: ptr(&c), len(1) {
}
constexpr ConstStringRef(const char *const ptr) noexcept
: ptr(ptr), len(constLength(ptr)) {
}
constexpr ConstStringRef(const char *const ptr, const size_t length) noexcept
: ptr(ptr), len(length) {
}
template <size_t Length>
static constexpr ConstStringRef fromArray(const char (&array)[Length]) noexcept {
return ConstStringRef(array, Length);
}
ConstStringRef(const std::string &str) noexcept
: ptr(str.data()), len(str.length()) {
}
constexpr ConstStringRef substr(int offset, int len) const noexcept {
if (len >= 0) {
return ConstStringRef(this->ptr + offset, len);
} else {
return ConstStringRef(this->ptr + offset, this->len + len - offset);
}
}
constexpr ConstStringRef substr(int offset) const noexcept {
return ConstStringRef(this->ptr + offset, this->len - offset);
}
constexpr ConstStringRef truncated(int len) const noexcept {
if (len >= 0) {
return ConstStringRef(this->ptr, len);
} else {
return ConstStringRef(this->ptr, this->len + len);
}
}
constexpr const char *data() const noexcept {
return ptr;
}
constexpr char operator[](size_t pos) const noexcept {
return ptr[pos];
}
constexpr char operator[](int pos) const noexcept {
return ptr[pos];
}
explicit operator std::string() const {
return str();
}
std::string str() const {
return std::string(ptr, len);
}
constexpr size_t size() const noexcept {
return len;
}
constexpr size_t length() const noexcept {
return len;
}
constexpr bool empty() const noexcept {
return len == 0;
}
constexpr const char *begin() const noexcept {
return ptr;
}
constexpr const char *end() const noexcept {
return ptr + len;
}
constexpr bool contains(const char *subString) const noexcept {
const char *findBeg = ptr;
const char *findEnd = ptr + len;
while (findBeg != findEnd) {
const char *lhs = findBeg;
const char *rhs = subString;
while ((lhs < findEnd) && (*lhs == *rhs) && ('\0' != *rhs)) {
++lhs;
++rhs;
}
if ('\0' == *rhs) {
return true;
}
++findBeg;
}
return false;
}
constexpr bool startsWith(const char *subString) const noexcept {
const char *findEnd = ptr + len;
const char *lhs = ptr;
const char *rhs = subString;
while ((lhs < findEnd) && (*lhs == *rhs) && ('\0' != *rhs)) {
++lhs;
++rhs;
}
return ('\0' == *rhs);
}
protected:
ConstStringRef(std::nullptr_t) = delete;
const char *ptr = nullptr;
size_t len = 0U;
};
constexpr bool equals(const ConstStringRef &lhs, const ConstStringRef &rhs) {
if (lhs.size() != rhs.size()) {
return false;
}
for (size_t i = 0, e = lhs.size(); i < e; ++i) {
if (lhs[i] != rhs[i]) {
return false;
}
}
return true;
}
constexpr bool equals(const ConstStringRef &lhs, const char *rhs) {
size_t i = 0;
for (size_t e = lhs.size(); i < e; ++i) {
if (lhs[i] != rhs[i]) {
return false;
}
if ((rhs[i] == '\0') && (i + 1 < e)) {
return false;
}
}
return (rhs[i] == '\0');
}
constexpr bool operator==(const ConstStringRef &lhs, const ConstStringRef &rhs) {
return equals(lhs, rhs);
}
constexpr bool operator==(const ConstStringRef &lhs, const char *rhs) {
return equals(lhs, rhs);
}
constexpr bool operator==(const char *lhs, const ConstStringRef &rhs) {
return equals(rhs, lhs);
}
constexpr bool operator!=(const ConstStringRef &lhs, const ConstStringRef &rhs) {
return false == equals(lhs, rhs);
}
constexpr bool operator!=(const ConstStringRef &lhs, const char *rhs) {
return false == equals(lhs, rhs);
}
constexpr bool operator!=(const char *lhs, const ConstStringRef &rhs) {
return false == equals(rhs, lhs);
}
constexpr bool equalsCaseInsesitive(const ConstStringRef &lhs, const ConstStringRef &rhs) {
if (lhs.size() != rhs.size()) {
return false;
}
constexpr auto caseDiff = 'a' - 'A';
for (size_t i = 0, e = lhs.size(); i < e; ++i) {
if ((lhs[i] != rhs[i]) & (lhs[i] + caseDiff != rhs[i]) & (lhs[i] != rhs[i] + caseDiff)) {
return false;
}
}
return true;
}
} // namespace NEO
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