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construct/ircd/util.cc

440 lines
7.8 KiB
C++

// Matrix Construct
//
// Copyright (C) Matrix Construct Developers, Authors & Contributors
// Copyright (C) 2016-2018 Jason Volk <jason@zemos.net>
//
// Permission to use, copy, modify, and/or distribute this software for any
// purpose with or without fee is hereby granted, provided that the above
// copyright notice and this permission notice is present in all copies. The
// full license for this software is available in the LICENSE file.
///////////////////////////////////////////////////////////////////////////////
//
// util/util.h
//
size_t
ircd::util::size(std::ostream &s)
{
const auto cur(s.tellp());
s.seekp(0, std::ios::end);
const auto ret(s.tellp());
s.seekp(cur, std::ios::beg);
return ret;
}
///////////////////////////////////////////////////////////////////////////////
//
// util/env.h
//
ircd::string_view
ircd::util::getenv(const string_view &key)
{
thread_local char keystr[128];
if(unlikely(size(key) >= sizeof(keystr)))
throw error
{
"getenv(): variable key is too long."
};
// Ensure the key is null terminated for the std:: call.
const size_t len
{
strlcpy(keystr, key)
};
const string_view var
{
std::getenv(keystr)
};
return var;
}
///////////////////////////////////////////////////////////////////////////////
//
// util/pretty.h
//
//
// Human readable time suite
//
ircd::string_view
ircd::util::pretty_nanoseconds(const mutable_buffer &out,
const long double &ns)
{
static const std::array<string_view, 7> unit
{
"nanoseconds",
"microseconds",
"milliseconds",
"seconds",
"minutes",
"hours",
"days",
};
auto pos(0);
long double val(ns);
// nanoseconds -> microseconds
if(val > 1000.0)
{
val /= 1000;
++pos;
}
else goto done;
// microseconds -> milliseconds
if(val > 1000.0)
{
val /= 1000;
++pos;
}
else goto done;
// milliseconds -> seconds
if(val > 1000.0)
{
val /= 1000;
++pos;
}
else goto done;
// seconds -> minutes
if(val > 60.0)
{
val /= 60;
++pos;
}
else goto done;
// minutes -> hours
if(val > 60.0)
{
val /= 60;
++pos;
}
else goto done;
// hours -> days
if(val > 12.0)
{
val /= 12;
++pos;
}
else goto done;
done:
return fmt::sprintf
{
out, "%.2lf %s",
val,
unit.at(pos)
};
}
//
// Human readable space suite
//
decltype(ircd::util::pretty_size_fmt)
ircd::util::pretty_size_fmt
{
"%.2lf %s (%lu)"
};
decltype(ircd::util::pretty_only_size_fmt)
ircd::util::pretty_only_size_fmt
{
"%.2lf %s",
};
std::string
ircd::util::pretty_only(const human_readable_size &value)
{
return util::string(32, [&value]
(const mutable_buffer &out)
{
return pretty_only(out, value);
});
}
ircd::string_view
ircd::util::pretty_only(const mutable_buffer &out,
const human_readable_size &value)
try
{
return fmt::sprintf
{
out, pretty_only_size_fmt,
std::get<long double>(value),
std::get<const string_view &>(value)
};
}
catch(const std::out_of_range &e)
{
return fmt::sprintf
{
out, "%lu B",
std::get<uint64_t>(value)
};
}
std::string
ircd::util::pretty(const human_readable_size &value)
{
return pretty(value, pretty_size_fmt);
}
ircd::string_view
ircd::util::pretty(const mutable_buffer &out,
const human_readable_size &value)
{
return pretty(out, pretty_size_fmt, value);
}
std::string
ircd::util::pretty(const human_readable_size &value,
const string_view &fmt)
{
return util::string(64, [&value, &fmt]
(const mutable_buffer &out)
{
return pretty(out, fmt, value);
});
}
ircd::string_view
ircd::util::pretty(const mutable_buffer &out,
const string_view &fmt,
const human_readable_size &value)
try
{
return fmt::sprintf
{
out, fmt,
std::get<long double>(value),
std::get<const string_view &>(value),
std::get<uint64_t>(value)
};
}
catch(const std::out_of_range &e)
{
return fmt::sprintf
{
out, "%lu B",
std::get<uint64_t>(value)
};
}
ircd::human_readable_size
ircd::util::iec(const uint64_t &value)
{
static const std::array<string_view, 7> unit
{
"B", "KiB", "MiB", "GiB", "TiB", "PiB", "EiB"
};
auto pos(0);
long double v(value);
for(; v > 1024.0; v /= 1024.0, ++pos);
return
{
value, v, unit.at(pos)
};
}
ircd::human_readable_size
ircd::util::si(const uint64_t &value)
{
static const std::array<string_view, 7> unit
{
"B", "KB", "MB", "GB", "TB", "PB", "EB"
};
auto pos(0);
long double v(value);
for(; v > 1000.0; v /= 1000.0, ++pos);
return
{
value, v, unit.at(pos)
};
}
///////////////////////////////////////////////////////////////////////////////
//
// util/string.h
//
/// Close over the common pattern to write directly into a post-C++11 standard
/// string through the data() member requiring a const_cast. Closure returns
/// a view of the data actually written to the buffer.
std::string
ircd::util::string(const size_t &size,
const std::function<string_view (const mutable_buffer &)> &closure)
{
return string(size, [&closure]
(const mutable_buffer &buffer)
{
return ircd::size(closure(buffer));
});
}
/// Close over the common pattern to write directly into a post-C++11 standard
/// string through the data() member requiring a const_cast. Closure returns
/// the final size of the data written into the buffer.
std::string
ircd::util::string(const size_t &size,
const std::function<size_t (const mutable_buffer &)> &closure)
{
std::string ret(size, char{});
const mutable_buffer buf
{
const_cast<char *>(ret.data()), ret.size()
};
const size_t consumed
{
closure(buf)
};
assert(consumed <= buffer::size(buf));
data(buf)[consumed] = '\0';
ret.resize(consumed);
return ret;
}
std::string
ircd::util::string(const char *const &buf,
const size_t &size)
{
return std::string{buf, size};
}
std::string
ircd::util::string(const uint8_t *const &buf,
const size_t &size)
{
return string(reinterpret_cast<const char *>(buf), size);
}
///////////////////////////////////////////////////////////////////////////////
//
// util/timer.h
//
ircd::util::timer::timer(const std::function<void ()> &func)
:timer{}
{
func();
stop();
}
void
ircd::util::timer::stop()
{
if(stopped())
return;
const auto now(clock::now());
accumulator += std::chrono::duration_cast<decltype(accumulator)>(now - start);
start = clock::time_point::min();
}
void
ircd::util::timer::cont()
{
if(!stopped())
{
const auto now(clock::now());
accumulator += std::chrono::duration_cast<decltype(accumulator)>(now - start);
}
start = clock::now();
}
bool
ircd::util::timer::stopped()
const
{
return start == clock::time_point::min();
}
///////////////////////////////////////////////////////////////////////////////
//
// util/u2a.h
//
std::string
ircd::util::u2a(const const_buffer &in)
{
return string(size(in) * 2, [&in]
(const mutable_buffer &out)
{
return u2a(out, in);
});
}
ircd::string_view
ircd::util::u2a(const mutable_buffer &out,
const const_buffer &in)
{
char *p(data(out));
for(size_t i(0); i < size(in) && p + 2 <= end(out); ++i)
{
char tmp[3];
::snprintf(tmp, sizeof(tmp), "%02x", in[i]);
*p++ = tmp[0];
*p++ = tmp[1];
}
return { data(out), p };
}
ircd::const_buffer
ircd::util::a2u(const mutable_buffer &out,
const const_buffer &in)
{
const size_t len{size(in) / 2};
for(size_t i(0); i < len; ++i)
{
const char gl[3]
{
in[i * 2],
in[i * 2 + 1],
'\0'
};
out[i] = strtol(gl, nullptr, 16);
}
return { data(out), len };
}
///////////////////////////////////////////////////////////////////////////////
//
// util/what.h
//
/// Get what() from exception_ptr
///
ircd::string_view
ircd::util::what(const std::exception_ptr eptr)
noexcept try
{
if(likely(eptr))
std::rethrow_exception(eptr);
return {};
}
catch(const std::exception &e)
{
return e.what();
}
catch(...)
{
return {};
}