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/*
* Copyright (C) 2015 The Android Open Source Project
*
* 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.
*/
#pragma once
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <limits>
#include <string>
#include <type_traits>
namespace android {
namespace base {
// Parses the unsigned decimal or hexadecimal integer in the string 's' and sets
// 'out' to that value if it is specified. Optionally allows the caller to define
// a 'max' beyond which otherwise valid values will be rejected. Returns boolean
// success; 'out' is untouched if parsing fails.
template <typename T>
bool ParseUint(const char* s, T* out, T max = std::numeric_limits<T>::max(),
bool allow_suffixes = false) {
static_assert(std::is_unsigned<T>::value, "ParseUint can only be used with unsigned types");
while (isspace(*s)) {
s++;
}
if (s[0] == '-') {
errno = EINVAL;
return false;
}
int base = (s[0] == '0' && (s[1] == 'x' || s[1] == 'X')) ? 16 : 10;
errno = 0;
char* end;
unsigned long long int result = strtoull(s, &end, base);
if (errno != 0) return false;
if (end == s) {
errno = EINVAL;
return false;
}
if (*end != '\0') {
const char* suffixes = "bkmgtpe";
const char* suffix;
if ((!allow_suffixes || (suffix = strchr(suffixes, tolower(*end))) == nullptr) ||
__builtin_mul_overflow(result, 1ULL << (10 * (suffix - suffixes)), &result)) {
errno = EINVAL;
return false;
}
}
if (max < result) {
errno = ERANGE;
return false;
}
if (out != nullptr) {
*out = static_cast<T>(result);
}
return true;
}
// TODO: string_view
template <typename T>
bool ParseUint(const std::string& s, T* out, T max = std::numeric_limits<T>::max(),
bool allow_suffixes = false) {
return ParseUint(s.c_str(), out, max, allow_suffixes);
}
template <typename T>
bool ParseByteCount(const char* s, T* out, T max = std::numeric_limits<T>::max()) {
return ParseUint(s, out, max, true);
}
// TODO: string_view
template <typename T>
bool ParseByteCount(const std::string& s, T* out, T max = std::numeric_limits<T>::max()) {
return ParseByteCount(s.c_str(), out, max);
}
// Parses the signed decimal or hexadecimal integer in the string 's' and sets
// 'out' to that value if it is specified. Optionally allows the caller to define
// a 'min' and 'max' beyond which otherwise valid values will be rejected. Returns
// boolean success; 'out' is untouched if parsing fails.
template <typename T>
bool ParseInt(const char* s, T* out,
T min = std::numeric_limits<T>::min(),
T max = std::numeric_limits<T>::max()) {
static_assert(std::is_signed<T>::value, "ParseInt can only be used with signed types");
while (isspace(*s)) {
s++;
}
int base = (s[0] == '0' && (s[1] == 'x' || s[1] == 'X')) ? 16 : 10;
errno = 0;
char* end;
long long int result = strtoll(s, &end, base);
if (errno != 0) {
return false;
}
if (s == end || *end != '\0') {
errno = EINVAL;
return false;
}
if (result < min || max < result) {
errno = ERANGE;
return false;
}
if (out != nullptr) {
*out = static_cast<T>(result);
}
return true;
}
// TODO: string_view
template <typename T>
bool ParseInt(const std::string& s, T* out,
T min = std::numeric_limits<T>::min(),
T max = std::numeric_limits<T>::max()) {
return ParseInt(s.c_str(), out, min, max);
}
} // namespace base
} // namespace android