0
0
Fork 0
mirror of https://github.com/matrix-construct/construct synced 2024-12-11 08:02:59 +01:00
construct/ircd/util.cc

515 lines
9.7 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;
}
bool
ircd::util::for_each_env(const string_view &prefix,
const env_closure &closure)
{
return for_each_env([&prefix, &closure]
(const auto &key, const auto &val)
{
if(!startswith(key, prefix))
return true;
return closure(key, val);
});
}
bool
ircd::util::for_each_env(const env_closure &closure)
{
assert(environ);
for(char **env(environ); *env; ++env)
{
const auto &[key, val]
{
split(*env, '=')
};
if(!closure(key, val))
return false;
}
return true;
}
///////////////////////////////////////////////////////////////////////////////
//
// util/pretty.h
//
//
// Human readable time suite
//
namespace ircd { inline namespace util
{
using pretty_time_formats = std::array<string_view, 2>;
using pretty_time_element = std::tuple<pretty_time_formats, long double>;
template<size_t i,
class T>
static string_view pretty(const mutable_buffer &, const T &, const uint &fmt);
[[gnu::visibility("internal")]]
extern const std::array<pretty_time_element, 9> pretty_time_unit;
}}
decltype(ircd::util::pretty_time_unit)
ircd::util::pretty_time_unit
{{
// fmt=0 fmt=1
{ { "nanoseconds", "ns" }, 1000.0L },
{ { "microseconds", "us" }, 1000.0L },
{ { "milliseconds", "ms" }, 1000.0L },
{ { "seconds", "s" }, 60.0L },
{ { "minutes", "m" }, 60.0L },
{ { "hours", "h" }, 24.0L },
{ { "days", "d" }, 7.0L },
{ { "weeks", "w" }, 4.0L },
{ { "months", "M" }, 12.0L },
}};
template<size_t i,
class T>
inline ircd::string_view
ircd::util::pretty(const mutable_buffer &out,
const T &dur,
const uint &fmt)
{
static const auto &unit
{
pretty_time_unit
};
const string_view &fmtstr
{
fmt == 1?
"%.2lf%s"_sv:
"%.2lf %s"_sv
};
size_t pos(i);
long double val(dur.count());
for(; val > std::get<1>(unit.at(pos)) && pos < unit.size() - 1; ++pos)
val /= std::get<1>(unit.at(pos));
return fmt::sprintf
{
out, fmtstr,
val,
std::get<0>(unit.at(pos)).at(fmt)
};
}
ircd::string_view
ircd::util::pretty(const mutable_buffer &out,
const nanoseconds &val,
const uint &fmt)
{
return pretty<0>(out, val, fmt);
}
ircd::string_view
ircd::util::pretty(const mutable_buffer &out,
const microseconds &val,
const uint &fmt)
{
return pretty<1>(out, val, fmt);
}
ircd::string_view
ircd::util::pretty(const mutable_buffer &out,
const milliseconds &val,
const uint &fmt)
{
return pretty<2>(out, val, fmt);
}
ircd::string_view
ircd::util::pretty(const mutable_buffer &out,
const seconds &val,
const uint &fmt)
{
return pretty<3>(out, val, fmt);
}
//
// Human readable space suite
//
decltype(ircd::util::pretty_fmt)
ircd::util::pretty_fmt
{
"%.2lf %s (%lu)"_sv,
"%.2lf %s"_sv,
"%.2lf%s"_sv,
string_view{},
};
std::string
ircd::util::pretty(const human_readable_size &value,
const uint &fmt)
{
return pretty(value, pretty_fmt[fmt]);
}
ircd::string_view
ircd::util::pretty(const mutable_buffer &out,
const human_readable_size &value,
const uint &fmt)
{
return pretty(out, pretty_fmt[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",
std::get<uint64_t>(value)
};
}
ircd::human_readable_size
ircd::util::si(const uint64_t &value)
{
static const std::array<string_view, 7> unit
{
" ", "K", "M", "G", "T", "P", "E"
};
auto pos(0);
long double v(value);
for(; v > 1000.0L; v /= 1000.0L, ++pos);
return
{
value, v, unit.at(pos)
};
}
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 > 1024.0L; v /= 1024.0L, ++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 string_closure_view &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 string_closure_size &closure)
{
const size_t alloc_size
{
size & ~SHRINK_TO_FIT
};
std::string ret(alloc_size, char{});
const mutable_buffer buf
{
mutable_cast(ret.data()), ret.size()
};
const size_t consumed
{
closure(buf)
};
assert(consumed <= buffer::size(buf));
data(buf)[consumed] = '\0';
ret.resize(consumed);
if(size & SHRINK_TO_FIT)
ret.shrink_to_fit();
return ret;
}
std::string
ircd::util::string(const const_buffer &buf)
{
return string(data(buf), size(buf));
}
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()
{
const auto now
{
!stopped()?
clock::now():
start
};
const auto elapsed
{
duration_cast<decltype(accumulator)>(now - start)
};
accumulator += elapsed;
start = clock::time_point::min();
}
void
ircd::util::timer::cont()
{
const auto now
{
clock::now()
};
const auto elapsed
{
!stopped()?
duration_cast<decltype(accumulator)>(now - start):
decltype(accumulator)(0)
};
accumulator += elapsed;
start = now;
}
std::string
ircd::util::timer::pretty(const int &fmt)
const
{
return util::pretty(at<nanoseconds>(), fmt);
}
ircd::string_view
ircd::util::timer::pretty(const mutable_buffer &out,
const int &fmt)
const
{
return util::pretty(out, at<nanoseconds>(), fmt);
}
///////////////////////////////////////////////////////////////////////////////
//
// 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", uint8_t(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/unwind.h
//
ircd::util::unwind_defer::~unwind_defer()
noexcept
{
[[clang::always_destroy]]
static ios::descriptor descriptor
{
"ircd.unwind"
};
ircd::dispatch
{
descriptor, ios::defer, std::move(func)
};
}
///////////////////////////////////////////////////////////////////////////////
//
// 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 {};
}