diff options
Diffstat (limited to 'src/libutil/util.hh')
-rw-r--r-- | src/libutil/util.hh | 28 |
1 files changed, 25 insertions, 3 deletions
diff --git a/src/libutil/util.hh b/src/libutil/util.hh index 7a4d5fe92..ab0bd865a 100644 --- a/src/libutil/util.hh +++ b/src/libutil/util.hh @@ -401,12 +401,34 @@ template<class N> std::optional<N> string2Int(const std::string & s) { if (s.substr(0, 1) == "-" && !std::numeric_limits<N>::is_signed) - return {}; + return std::nullopt; std::istringstream str(s); N n; str >> n; if (str && str.get() == EOF) return n; - return {}; + return std::nullopt; +} + +/* Like string2Int(), but support an optional suffix 'K', 'M', 'G' or + 'T' denoting a binary unit prefix. */ +template<class N> +N string2IntWithUnitPrefix(std::string s) +{ + N multiplier = 1; + if (!s.empty()) { + char u = std::toupper(*s.rbegin()); + if (std::isalpha(u)) { + if (u == 'K') multiplier = 1ULL << 10; + else if (u == 'M') multiplier = 1ULL << 20; + else if (u == 'G') multiplier = 1ULL << 30; + else if (u == 'T') multiplier = 1ULL << 40; + else throw UsageError("invalid unit specifier '%1%'", u); + s.resize(s.size() - 1); + } + } + if (auto n = string2Int<N>(s)) + return *n * multiplier; + throw UsageError("'%s' is not an integer", s); } /* Parse a string into a float. */ @@ -417,7 +439,7 @@ std::optional<N> string2Float(const string & s) N n; str >> n; if (str && str.get() == EOF) return n; - return {}; + return std::nullopt; } |