external/bsd/kyua-cli/dist/utils/units.hpp

   1 // Copyright 2012 Google Inc.
   2 // All rights reserved.
   3 //
   4 // Redistribution and use in source and binary forms, with or without
   5 // modification, are permitted provided that the following conditions are
   6 // met:
   7 //
   8 // * Redistributions of source code must retain the above copyright
   9 //   notice, this list of conditions and the following disclaimer.
  10 // * Redistributions in binary form must reproduce the above copyright
  11 //   notice, this list of conditions and the following disclaimer in the
  12 //   documentation and/or other materials provided with the distribution.
  13 // * Neither the name of Google Inc. nor the names of its contributors
  14 //   may be used to endorse or promote products derived from this software
  15 //   without specific prior written permission.
  16 //
  17 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  18 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  19 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  20 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  21 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  22 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  23 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  24 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  25 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  26 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  27 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  28
  29 /// \file utils/units.hpp
  30 /// Formatters and parsers of user-friendly units.
  31
  32 #if !defined(UTILS_UNITS_HPP)
  33 #define UTILS_UNITS_HPP
  34
  35 extern "C" {
  36 #include <stdint.h>
  37 }
  38
  39 #include <istream>
  40 #include <ostream>
  41 #include <string>
  42
  43 namespace utils {
  44 namespace units {
  45
  46
  47 namespace {
  48
  49 /// Constant representing 1 kilobyte.
  50 const uint64_t KB = int64_t(1) << 10;
  51
  52 /// Constant representing 1 megabyte.
  53 const uint64_t MB = int64_t(1) << 20;
  54
  55 /// Constant representing 1 gigabyte.
  56 const uint64_t GB = int64_t(1) << 30;
  57
  58 /// Constant representing 1 terabyte.
  59 const uint64_t TB = int64_t(1) << 40;
  60
  61 }  // anonymous namespace
  62
  63
  64 /// Representation of a bytes quantity.
  65 ///
  66 /// The purpose of this class is to represent an amount of bytes in a semantic
  67 /// manner, and to provide functions to format such numbers for nice user
  68 /// presentation and to parse back such numbers.
  69 ///
  70 /// The input follows this regular expression: [0-9]+(|\.[0-9]+)[GgKkMmTt]?
  71 /// The output follows this regular expression: [0-9]+\.[0-9]{3}[GKMT]?
  72 class bytes {
  73     /// Raw representation, in bytes, of the quantity.
  74     uint64_t _count;
  75
  76 public:
  77     bytes(void);
  78     explicit bytes(const uint64_t);
  79
  80     static bytes parse(const std::string&);
  81     std::string format(void) const;
  82
  83     operator uint64_t(void) const;
  84 };
  85
  86
  87 std::istream& operator>>(std::istream&, bytes&);
  88 std::ostream& operator<<(std::ostream&, const bytes&);
  89
  90
  91 }  // namespace units
  92 }  // namespace utils
  93
  94 #endif  // !defined(UTILS_UNITS_HPP)