1 // Copyright 2012 The Kyua Authors.
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
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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
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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 #include "utils/units.hpp"
30
31 extern "C" {
32 #include <stdint.h>
33 }
34
35 #include <stdexcept>
36
37 #include "utils/format/macros.hpp"
38 #include "utils/text/exceptions.hpp"
39 #include "utils/text/operations.ipp"
40
41 namespace units = utils::units;
42
43
44 /// Constructs a zero bytes quantity.
bytes(void)45 units::bytes::bytes(void) :
46 _count(0)
47 {
48 }
49
50
51 /// Constructs an arbitrary bytes quantity.
52 ///
53 /// \param count_ The amount of bytes in the quantity.
bytes(const uint64_t count_)54 units::bytes::bytes(const uint64_t count_) :
55 _count(count_)
56 {
57 }
58
59
60 /// Parses a string into a bytes quantity.
61 ///
62 /// \param in_str The user-provided string to be converted.
63 ///
64 /// \return The converted bytes quantity.
65 ///
66 /// \throw std::runtime_error If the input string is empty or invalid.
67 units::bytes
parse(const std::string & in_str)68 units::bytes::parse(const std::string& in_str)
69 {
70 if (in_str.empty())
71 throw std::runtime_error("Bytes quantity cannot be empty");
72
73 uint64_t multiplier;
74 std::string str = in_str;
75 {
76 const char unit = str[str.length() - 1];
77 switch (unit) {
78 case 'T': case 't': multiplier = TB; break;
79 case 'G': case 'g': multiplier = GB; break;
80 case 'M': case 'm': multiplier = MB; break;
81 case 'K': case 'k': multiplier = KB; break;
82 default: multiplier = 1;
83 }
84 if (multiplier != 1)
85 str.erase(str.length() - 1);
86 }
87
88 if (str.empty())
89 throw std::runtime_error("Bytes quantity cannot be empty");
90 if (str[0] == '.' || str[str.length() - 1] == '.') {
91 // The standard parser for float values accepts things like ".3" and
92 // "3.", which means that we would interpret ".3K" and "3.K" as valid
93 // quantities. I think this is ugly and should not be allowed, so
94 // special-case this condition and just error out.
95 throw std::runtime_error(F("Invalid bytes quantity '%s'") % in_str);
96 }
97
98 double count;
99 try {
100 count = text::to_type< double >(str);
101 } catch (const text::value_error& e) {
102 throw std::runtime_error(F("Invalid bytes quantity '%s'") % in_str);
103 }
104
105 return bytes(uint64_t(count * multiplier));
106 }
107
108
109 /// Formats a bytes quantity for user consumption.
110 ///
111 /// \return A textual representation of the bytes quantiy.
112 std::string
format(void) const113 units::bytes::format(void) const
114 {
115 if (_count >= TB) {
116 return F("%.2sT") % (static_cast< float >(_count) / TB);
117 } else if (_count >= GB) {
118 return F("%.2sG") % (static_cast< float >(_count) / GB);
119 } else if (_count >= MB) {
120 return F("%.2sM") % (static_cast< float >(_count) / MB);
121 } else if (_count >= KB) {
122 return F("%.2sK") % (static_cast< float >(_count) / KB);
123 } else {
124 return F("%s") % _count;
125 }
126 }
127
128
129 /// Implicit conversion to an integral representation.
operator uint64_t(void) const130 units::bytes::operator uint64_t(void) const
131 {
132 return _count;
133 }
134
135
136 /// Extracts a bytes quantity from a stream.
137 ///
138 /// \param input The stream from which to read a single word representing the
139 /// bytes quantity.
140 /// \param rhs The variable into which to store the parsed value.
141 ///
142 /// \return The input stream.
143 ///
144 /// \post The bad bit of input is set to 1 if the parsing failed.
145 std::istream&
operator >>(std::istream & input,bytes & rhs)146 units::operator>>(std::istream& input, bytes& rhs)
147 {
148 std::string word;
149 input >> word;
150 if (input.good() || input.eof()) {
151 try {
152 rhs = bytes::parse(word);
153 } catch (const std::runtime_error& e) {
154 input.setstate(std::ios::badbit);
155 }
156 }
157 return input;
158 }
159
160
161 /// Injects a bytes quantity into a stream.
162 ///
163 /// \param output The stream into which to inject the bytes quantity as a
164 /// user-readable string.
165 /// \param rhs The bytes quantity to format.
166 ///
167 /// \return The output stream.
168 std::ostream&
operator <<(std::ostream & output,const bytes & rhs)169 units::operator<<(std::ostream& output, const bytes& rhs)
170 {
171 return (output << rhs.format());
172 }
173