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-rw-r--r--src/common/strtol.h179
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diff --git a/src/common/strtol.h b/src/common/strtol.h
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+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+/*
+ * Ceph - scalable distributed file system
+ *
+ * Copyright (C) 2011 New Dream Network
+ *
+ * This is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License version 2.1, as published by the Free Software
+ * Foundation. See file COPYING.
+ *
+ */
+
+#ifndef CEPH_COMMON_STRTOL_H
+#define CEPH_COMMON_STRTOL_H
+
+#if __has_include(<charconv>)
+#include <charconv>
+#endif // __has_include(<charconv>)
+#include <cinttypes>
+#include <cstdlib>
+#include <optional>
+#include <string>
+#include <string_view>
+#include <system_error>
+#include <type_traits>
+
+
+namespace ceph {
+#if __has_include(<charconv>)
+// Wrappers around std::from_chars.
+//
+// Why do we want this instead of strtol and friends? Because the
+// string doesn't have to be NUL-terminated! (Also, for a lot of
+// purposes, just putting a string_view in and getting an optional out
+// is friendly.)
+//
+// Returns the found number on success. Returns an empty optional on
+// failure OR on trailing characters.
+template<typename T>
+auto parse(std::string_view s, int base = 10)
+ -> std::enable_if_t<std::is_integral_v<T>, std::optional<T>>
+{
+ T t;
+ auto r = std::from_chars(s.data(), s.data() + s.size(), t, base);
+ if ((r.ec != std::errc{}) || (r.ptr != s.data() + s.size())) {
+ return std::nullopt;
+ }
+ return t;
+}
+
+// As above, but succeed on trailing characters and trim the supplied
+// string_view to remove the parsed number. Set the supplied
+// string_view to empty if it ends with the number.
+template<typename T>
+auto consume(std::string_view& s, int base = 10)
+ -> std::enable_if_t<std::is_integral_v<T>, std::optional<T>>
+{
+ T t;
+ auto r = std::from_chars(s.data(), s.data() + s.size(), t, base);
+ if (r.ec != std::errc{})
+ return std::nullopt;
+
+ if (r.ptr == s.data() + s.size()) {
+ s = std::string_view{};
+ } else {
+ s.remove_prefix(r.ptr - s.data());
+ }
+ return t;
+}
+// Sadly GCC is missing the floating point versions.
+#else // __has_include(<charconv>)
+template<typename T>
+auto parse(std::string_view sv, int base = 10)
+ -> std::enable_if_t<std::is_integral_v<T>, std::optional<T>>
+{
+ std::string s(sv);
+ char* end = nullptr;
+ std::conditional_t<std::is_signed_v<T>, std::intmax_t, std::uintmax_t> v;
+ errno = 0;
+
+ if (s.size() > 0 && std::isspace(s[0]))
+ return std::nullopt;
+
+ if constexpr (std::is_signed_v<T>) {
+ v = std::strtoimax(s.data(), &end, base);
+ } else {
+ if (s.size() > 0 && s[0] == '-')
+ return std::nullopt;
+ v = std::strtoumax(s.data(), &end, base);
+ }
+ if (errno != 0 ||
+ end != s.data() + s.size() ||
+ v > std::numeric_limits<T>::max() ||
+ v < std::numeric_limits<T>::min())
+ return std::nullopt;
+ return static_cast<T>(v);
+}
+
+template<typename T>
+auto consume(std::string_view& sv, int base = 10)
+ -> std::enable_if_t<std::is_integral_v<T>, std::optional<T>>
+{
+ std::string s(sv);
+ char* end = nullptr;
+ std::conditional_t<std::is_signed_v<T>, std::intmax_t, std::uintmax_t> v;
+ errno = 0;
+
+ if (s.size() > 0 && std::isspace(s[0]))
+ return std::nullopt;
+
+ if constexpr (std::is_signed_v<T>) {
+ v = std::strtoimax(s.data(), &end, base);
+ } else {
+ if (s.size() > 0 && s[0] == '-')
+ return std::nullopt;
+ v = std::strtoumax(s.data(), &end, base);
+ }
+ if (errno != 0 ||
+ end == s.data() ||
+ v > std::numeric_limits<T>::max() ||
+ v < std::numeric_limits<T>::min())
+ return std::nullopt;
+ if (end == s.data() + s.size()) {
+ sv = std::string_view{};
+ } else {
+ sv.remove_prefix(end - s.data());
+ }
+ return static_cast<T>(v);
+}
+#endif // __has_include(<charconv>)
+} // namespace ceph
+
+bool strict_strtob(const char* str, std::string *err);
+
+long long strict_strtoll(std::string_view str, int base, std::string *err);
+long long strict_strtoll(const char *str, int base, std::string *err);
+
+int strict_strtol(std::string_view str, int base, std::string *err);
+int strict_strtol(const char *str, int base, std::string *err);
+
+double strict_strtod(const char *str, std::string *err);
+
+float strict_strtof(const char *str, std::string *err);
+
+uint64_t strict_iecstrtoll(const char *str, std::string *err);
+
+template<typename T>
+T strict_iec_cast(const char *str, std::string *err);
+
+uint64_t strict_sistrtoll(const char *str, std::string *err);
+
+template<typename T>
+T strict_si_cast(const char *str, std::string *err);
+
+/* On enter buf points to the end of the buffer, e.g. where the least
+ * significant digit of the input number will be printed. Returns pointer to
+ * where the most significant digit were printed, including zero padding.
+ * Does NOT add zero at the end of buffer, this is responsibility of the caller.
+ */
+template<typename T, const unsigned base = 10, const unsigned width = 1>
+static inline
+char* ritoa(T u, char *buf)
+{
+ static_assert(std::is_unsigned_v<T>, "signed types are not supported");
+ static_assert(base <= 16, "extend character map below to support higher bases");
+ unsigned digits = 0;
+ while (u) {
+ *--buf = "0123456789abcdef"[u % base];
+ u /= base;
+ digits++;
+ }
+ while (digits++ < width)
+ *--buf = '0';
+ return buf;
+}
+
+#endif