1 //===- VersionTuple.cpp - Version Number Handling ---------------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file implements the VersionTuple class, which represents a version in
11 // the form major[.minor[.subminor]].
12 //
13 //===----------------------------------------------------------------------===//
14 #include "clang/Basic/VersionTuple.h"
15 #include "llvm/Support/raw_ostream.h"
16 
17 using namespace clang;
18 
getAsString() const19 std::string VersionTuple::getAsString() const {
20   std::string Result;
21   {
22     llvm::raw_string_ostream Out(Result);
23     Out << *this;
24   }
25   return Result;
26 }
27 
operator <<(raw_ostream & Out,const VersionTuple & V)28 raw_ostream& clang::operator<<(raw_ostream &Out,
29                                      const VersionTuple &V) {
30   Out << V.getMajor();
31   if (Optional<unsigned> Minor = V.getMinor())
32     Out << (V.usesUnderscores() ? '_' : '.') << *Minor;
33   if (Optional<unsigned> Subminor = V.getSubminor())
34     Out << (V.usesUnderscores() ? '_' : '.') << *Subminor;
35   if (Optional<unsigned> Build = V.getBuild())
36     Out << (V.usesUnderscores() ? '_' : '.') << *Build;
37   return Out;
38 }
39 
parseInt(StringRef & input,unsigned & value)40 static bool parseInt(StringRef &input, unsigned &value) {
41   assert(value == 0);
42   if (input.empty()) return true;
43 
44   char next = input[0];
45   input = input.substr(1);
46   if (next < '0' || next > '9') return true;
47   value = (unsigned) (next - '0');
48 
49   while (!input.empty()) {
50     next = input[0];
51     if (next < '0' || next > '9') return false;
52     input = input.substr(1);
53     value = value * 10 + (unsigned) (next - '0');
54   }
55 
56   return false;
57 }
58 
tryParse(StringRef input)59 bool VersionTuple::tryParse(StringRef input) {
60   unsigned major = 0, minor = 0, micro = 0, build = 0;
61 
62   // Parse the major version, [0-9]+
63   if (parseInt(input, major)) return true;
64 
65   if (input.empty()) {
66     *this = VersionTuple(major);
67     return false;
68   }
69 
70   // If we're not done, parse the minor version, \.[0-9]+
71   if (input[0] != '.') return true;
72   input = input.substr(1);
73   if (parseInt(input, minor)) return true;
74 
75   if (input.empty()) {
76     *this = VersionTuple(major, minor);
77     return false;
78   }
79 
80   // If we're not done, parse the micro version, \.[0-9]+
81   if (input[0] != '.') return true;
82   input = input.substr(1);
83   if (parseInt(input, micro)) return true;
84 
85   if (input.empty()) {
86     *this = VersionTuple(major, minor, micro);
87     return false;
88   }
89 
90   // If we're not done, parse the micro version, \.[0-9]+
91   if (input[0] != '.') return true;
92   input = input.substr(1);
93   if (parseInt(input, build)) return true;
94 
95   // If we have characters left over, it's an error.
96   if (!input.empty()) return true;
97 
98   *this = VersionTuple(major, minor, micro, build);
99   return false;
100 }
101